xref: /titanic_51/usr/src/uts/sun/io/scsi/adapters/fas.c (revision 89b43686db1fe9681d80a7cf5662730cb9378cae)

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 * Copyright (c) 2011 Bayard G. Bell. All rights reserved.
 */


/*
 * ISSUES
 *
 * - more consistent error messages
 * - report name of device on errors?
 * - if wide target renegotiates sync, back to narrow?
 * - last_msgout is not accurate ????
 * - resolve XXXX
 * - improve msg reject code (use special msg reject handler)
 * - better use of IDE message
 * - keep track if ATN remains asserted and target not going into
 *   a msg-out phase
 * - improve comments
 * - no slave accesses when start address is odd and dma hasn't started
 *   this affect asserting ATN
 */

/*
 * fas - QLogic fas366 wide/fast SCSI Processor HBA driver with
 *	tagged and non-tagged queueing support
 */
#if defined(lint) && !defined(DEBUG)
#define	DEBUG	1
#define	FASDEBUG
#endif

#define	DMA_REG_TRACING 	/* enable dma register access tracing */


/*
 * standard header files
 */
#include <sys/note.h>
#include <sys/scsi/scsi.h>
#include <sys/file.h>
#include <sys/vtrace.h>

/*
 * private header files
 */
#include <sys/scsi/adapters/fasdma.h>
#include <sys/scsi/adapters/fasreg.h>
#include <sys/scsi/adapters/fasvar.h>
#include <sys/scsi/adapters/fascmd.h>
#include <sys/scsi/impl/scsi_reset_notify.h>

/*
 * tunables
 */
static int		fas_selection_timeout = 250; /* 250 milliseconds */
static uchar_t		fas_default_offset = DEFAULT_OFFSET;

/*
 * needed for presto support, do not remove
 */
static int		fas_enable_sbus64 = 1;

#ifdef	FASDEBUG
int			fasdebug = 0;
int			fasdebug_instance = -1; /* debug all instances */
static int		fas_burstsizes_limit = -1;
static int		fas_no_sync_wide_backoff = 0;
#endif	/* FASDEBUG */

/*
 * Local static data protected by global mutex
 */
static kmutex_t 	fas_global_mutex; /* to allow concurrent attach */

static int		fas_scsi_watchdog_tick; /* in seconds, for all	*/
					/* instances			*/
static clock_t		fas_tick;	/* fas_watch() interval in Hz	*/
static timeout_id_t	fas_reset_watch; /* timeout id for reset watch	*/
static timeout_id_t	fas_timeout_id = 0;
static int		fas_timeout_initted = 0;

static krwlock_t	fas_global_rwlock;

static void		*fas_state;	/* soft state ptr		*/
static struct fas	*fas_head;	/* link all softstate structures */
static struct fas	*fas_tail;	/* for fas_watch()		*/

static kmutex_t		fas_log_mutex;
static char		fas_log_buf[256];
_NOTE(MUTEX_PROTECTS_DATA(fas_global_mutex, fas_reset_watch))
_NOTE(DATA_READABLE_WITHOUT_LOCK(fas_state fas_head fas_tail \
	fas_scsi_watchdog_tick fas_tick))
_NOTE(SCHEME_PROTECTS_DATA("safe sharing", fas::f_quiesce_timeid))

/*
 * dma attribute structure for scsi engine
 */
static ddi_dma_attr_t dma_fasattr	= {
	DMA_ATTR_V0, (unsigned long long)0,
	(unsigned long long)0xffffffff, (unsigned long long)((1<<24)-1),
	1, DEFAULT_BURSTSIZE, 1,
	(unsigned long long)0xffffffff, (unsigned long long)0xffffffff,
	1, 512, 0
};

/*
 * optional torture test stuff
 */
#ifdef	FASDEBUG
#define	FAS_TEST
static int fas_ptest_emsgin;
static int fas_ptest_msgin;
static int fas_ptest_msg = -1;
static int fas_ptest_status;
static int fas_ptest_data_in;
static int fas_atest;
static int fas_atest_disc;
static int fas_atest_reconn;
static void fas_test_abort(struct fas *fas, int slot);
static int fas_rtest;
static int fas_rtest_type;
static void fas_test_reset(struct fas *fas, int slot);
static int fas_force_timeout;
static int fas_btest;
static int fas_test_stop;
static int fas_transport_busy;
static int fas_transport_busy_rqs;
static int fas_transport_reject;
static int fas_arqs_failure;
static int fas_tran_err;
static int fas_test_untagged;
static int fas_enable_untagged;
#endif

/*
 * warlock directives
 */
_NOTE(DATA_READABLE_WITHOUT_LOCK(dma fasdebug))
_NOTE(SCHEME_PROTECTS_DATA("just test variables", fas_transport_busy))
_NOTE(SCHEME_PROTECTS_DATA("just test variables", fas_transport_busy_rqs))
_NOTE(SCHEME_PROTECTS_DATA("just test variables", fas_transport_reject))
_NOTE(SCHEME_PROTECTS_DATA("just test variables", fas_arqs_failure))
_NOTE(SCHEME_PROTECTS_DATA("just test variables", fas_tran_err))
_NOTE(MUTEX_PROTECTS_DATA(fas_log_mutex, fas_log_buf))
_NOTE(MUTEX_PROTECTS_DATA(fas_global_mutex, fas_reset_watch))
_NOTE(DATA_READABLE_WITHOUT_LOCK(fas_state fas_head fas_tail \
	fas_scsi_watchdog_tick fas_tick))

/*
 * function prototypes
 *
 * scsa functions are exported by means of the transport table:
 */
static int fas_scsi_tgt_probe(struct scsi_device *sd,
    int (*waitfunc)(void));
static int fas_scsi_tgt_init(dev_info_t *, dev_info_t *,
    scsi_hba_tran_t *, struct scsi_device *);
static int fas_scsi_start(struct scsi_address *ap, struct scsi_pkt *pkt);
static int fas_scsi_abort(struct scsi_address *ap, struct scsi_pkt *pkt);
static int fas_scsi_reset(struct scsi_address *ap, int level);
static int fas_scsi_getcap(struct scsi_address *ap, char *cap, int whom);
static int fas_scsi_setcap(struct scsi_address *ap, char *cap, int value,
    int whom);
static struct scsi_pkt *fas_scsi_init_pkt(struct scsi_address *ap,
    struct scsi_pkt *pkt, struct buf *bp, int cmdlen, int statuslen,
    int tgtlen, int flags, int (*callback)(), caddr_t arg);
static void fas_scsi_destroy_pkt(struct scsi_address *ap, struct scsi_pkt *pkt);
static void fas_scsi_dmafree(struct scsi_address *ap,
    struct scsi_pkt *pkt);
static void fas_scsi_sync_pkt(struct scsi_address *ap,
    struct scsi_pkt *pkt);

/*
 * internal functions:
 */
static int fas_prepare_pkt(struct fas *fas, struct fas_cmd *sp);
static int fas_alloc_tag(struct fas *fas, struct fas_cmd *sp);
static int fas_accept_pkt(struct fas *fas, struct fas_cmd *sp, int flag);
static void fas_empty_waitQ(struct fas *fas);
static void fas_move_waitQ_to_readyQ(struct fas *fas);
static void fas_check_waitQ_and_mutex_exit(struct fas *fas);
static int fas_istart(struct fas *fas);
static int fas_ustart(struct fas *fas);
static int fas_startcmd(struct fas *fas, struct fas_cmd *sp);

static int fas_pkt_alloc_extern(struct fas *fas, struct fas_cmd *sp,
    int cmdlen, int tgtlen, int statuslen, int kf);
static void fas_pkt_destroy_extern(struct fas *fas, struct fas_cmd *sp);
static int fas_kmem_cache_constructor(void *buf, void *cdrarg, int kmflags);
static void fas_kmem_cache_destructor(void *buf, void *cdrarg);

static int fas_finish(struct fas *fas);
static void fas_handle_qfull(struct fas *fas, struct fas_cmd *sp);
static void fas_restart_cmd(void *);
static int fas_dopoll(struct fas *fas, int timeout);
static void fas_runpoll(struct fas *fas, short slot, struct fas_cmd *sp);
static uint_t fas_intr(caddr_t arg);
static int fas_intr_svc(struct	fas *fas);
static int fas_phasemanage(struct fas *fas);
static int fas_handle_unknown(struct fas *fas);
static int fas_handle_cmd_start(struct fas *fas);
static int fas_handle_cmd_done(struct fas *fas);
static int fas_handle_msg_out_start(struct fas *fas);
static int fas_handle_msg_out_done(struct fas *fas);
static int fas_handle_clearing(struct fas *fas);
static int fas_handle_data_start(struct fas *fas);
static int fas_handle_data_done(struct fas *fas);
static int fas_handle_c_cmplt(struct fas *fas);
static int fas_handle_msg_in_start(struct fas *fas);
static int fas_handle_more_msgin(struct fas *fas);
static int fas_handle_msg_in_done(struct fas *fas);
static int fas_onebyte_msg(struct fas *fas);
static int fas_twobyte_msg(struct fas *fas);
static int fas_multibyte_msg(struct fas *fas);
static void fas_revert_to_async(struct fas *fas, int tgt);
static int fas_finish_select(struct fas *fas);
static int fas_reselect_preempt(struct fas *fas);
static int fas_reconnect(struct fas *fas);
static int fas_handle_selection(struct fas *fas);
static void fas_head_of_readyQ(struct fas *fas, struct fas_cmd *sp);
static int fas_handle_gross_err(struct fas *fas);
static int fas_illegal_cmd_or_bus_reset(struct fas *fas);
static int fas_check_dma_error(struct fas *fas);

static void fas_make_sdtr(struct fas *fas, int msgout_offset, int target);
static void fas_make_wdtr(struct fas *fas, int msgout_offset, int target,
    int width);
static void fas_update_props(struct fas *fas, int tgt);
static void fas_update_this_prop(struct fas *fas, char *property, int value);

static int fas_commoncap(struct scsi_address *ap, char *cap, int val,
    int tgtonly, int doset);

static void fas_watch(void *arg);
static void fas_watchsubr(struct fas *fas);
static void fas_cmd_timeout(struct fas *fas, int slot);
static void fas_sync_wide_backoff(struct fas *fas, struct fas_cmd *sp,
    int slot);
static void fas_reset_sync_wide(struct fas *fas);
static void fas_set_wide_conf3(struct fas *fas, int target, int width);
static void fas_force_renegotiation(struct fas *fas, int target);

static int fas_set_new_window(struct fas *fas, struct fas_cmd *sp);
static int fas_restore_pointers(struct fas *fas, struct fas_cmd *sp);
static int fas_next_window(struct fas *fas, struct fas_cmd *sp, uint64_t end);

/*PRINTFLIKE3*/
static void fas_log(struct fas *fas, int level, const char *fmt, ...);
/*PRINTFLIKE2*/
static void fas_printf(struct fas *fas, const char *fmt, ...);
static void fas_printstate(struct fas *fas, char *msg);
static void fas_dump_cmd(struct fas *fas, struct fas_cmd *sp);
static void fas_short_dump_cmd(struct fas *fas, struct fas_cmd *sp);
static char *fas_state_name(ushort_t state);

static void fas_makeproxy_cmd(struct fas_cmd *sp,
    struct scsi_address *ap, struct scsi_pkt *pkt, int nmsg, ...);
static int fas_do_proxy_cmd(struct fas *fas, struct fas_cmd *sp,
    struct scsi_address *ap, char *what);

static void fas_internal_reset(struct fas *fas, int reset_action);
static int fas_alloc_active_slots(struct fas *fas, int slot, int flag);

static int fas_abort_curcmd(struct fas *fas);
static int fas_abort_cmd(struct fas *fas, struct fas_cmd *sp, int slot);
static int fas_do_scsi_abort(struct scsi_address *ap, struct scsi_pkt *pkt);
static int fas_do_scsi_reset(struct scsi_address *ap, int level);
static int fas_remove_from_readyQ(struct fas *fas, struct fas_cmd *sp,
    int slot);
static void fas_flush_readyQ(struct fas *fas, int slot);
static void fas_flush_tagQ(struct fas *fas, int slot);
static void fas_flush_cmd(struct fas *fas, struct fas_cmd *sp,
    uchar_t reason, uint_t stat);
static int fas_abort_connected_cmd(struct fas *fas, struct fas_cmd *sp,
    uchar_t msg);
static int fas_abort_disconnected_cmd(struct fas *fas, struct scsi_address *ap,
    struct fas_cmd *sp, uchar_t msg, int slot);
static void fas_mark_packets(struct fas *fas, int slot, uchar_t reason,
    uint_t stat);
static void fas_set_pkt_reason(struct fas *fas, struct fas_cmd *sp,
    uchar_t reason, uint_t stat);

static int fas_reset_bus(struct fas *fas);
static int fas_reset_recovery(struct fas *fas);
static int fas_reset_connected_cmd(struct fas *fas, struct scsi_address *ap);
static int fas_reset_disconnected_cmd(struct fas *fas, struct scsi_address *ap);
static void fas_start_watch_reset_delay(struct fas *);
static void fas_setup_reset_delay(struct fas *fas);
static void fas_watch_reset_delay(void *arg);
static int fas_watch_reset_delay_subr(struct fas *fas);
static void fas_reset_cleanup(struct fas *fas, int slot);
static int fas_scsi_reset_notify(struct scsi_address *ap, int flag,
    void (*callback)(caddr_t), caddr_t arg);
static int fas_scsi_quiesce(dev_info_t *hba_dip);
static int fas_scsi_unquiesce(dev_info_t *hba_dip);

static void fas_set_throttles(struct fas *fas, int slot,
    int n, int what);
static void fas_set_all_lun_throttles(struct fas *fas, int slot, int what);
static void fas_full_throttle(struct fas *fas, int slot);
static void fas_remove_cmd(struct fas *fas, struct fas_cmd *sp, int timeout);
static void fas_decrement_ncmds(struct fas *fas, struct fas_cmd *sp);

static int fas_quiesce_bus(struct fas *fas);
static int fas_unquiesce_bus(struct fas *fas);
static void fas_ncmds_checkdrain(void *arg);
static int fas_check_outstanding(struct fas *fas);

static int fas_create_arq_pkt(struct fas *fas, struct scsi_address *ap);
static int fas_delete_arq_pkt(struct fas *fas, struct scsi_address *ap);
static int fas_handle_sts_chk(struct fas *fas, struct fas_cmd *sp);
void fas_complete_arq_pkt(struct scsi_pkt *pkt);

void fas_call_pkt_comp(struct fas *fas, struct fas_cmd *sp);
void fas_empty_callbackQ(struct fas *fas);
int fas_init_callbacks(struct fas *fas);
void fas_destroy_callbacks(struct fas *fas);

static int fas_check_dma_error(struct fas *fas);
static int fas_init_chip(struct fas *fas, uchar_t id);

static void fas_read_fifo(struct fas *fas);
static void fas_write_fifo(struct fas *fas, uchar_t *buf, int length, int pad);

#ifdef FASDEBUG
static void fas_reg_cmd_write(struct fas *fas, uint8_t cmd);
static void fas_reg_write(struct fas *fas, volatile uint8_t *p, uint8_t what);
static uint8_t fas_reg_read(struct fas *fas, volatile uint8_t *p);

static void fas_dma_reg_write(struct fas *fas, volatile uint32_t *p,
    uint32_t what);
static uint32_t fas_dma_reg_read(struct fas *fas, volatile uint32_t *p);
#else
#define	fas_reg_cmd_write(fas, cmd) \
	fas->f_reg->fas_cmd = (cmd), fas->f_last_cmd = (cmd)
#define	fas_reg_write(fas, p, what)  *(p) = (what)
#define	fas_reg_read(fas, p) *(p)
#define	fas_dma_reg_write(fas, p, what)  *(p) = (what)
#define	fas_dma_reg_read(fas, p) *(p)
#endif

/*
 * autoconfiguration data and routines.
 */
static int fas_attach(dev_info_t *dev, ddi_attach_cmd_t cmd);
static int fas_detach(dev_info_t *dev, ddi_detach_cmd_t cmd);
static int fas_dr_detach(dev_info_t *dev);

static struct dev_ops fas_ops = {
	DEVO_REV,		/* devo_rev, */
	0,			/* refcnt  */
	ddi_no_info,		/* info */
	nulldev,		/* identify */
	nulldev,		/* probe */
	fas_attach,		/* attach */
	fas_detach,		/* detach */
	nodev,			/* reset */
	NULL,			/* driver operations */
	NULL,			/* bus operations */
	NULL,			/* power */
	ddi_quiesce_not_supported,	/* devo_quiesce */
};

static struct modldrv modldrv = {
	&mod_driverops, /* Type of module. This one is a driver */
	"FAS SCSI HBA Driver", /* Name of the module. */
	&fas_ops,	/* driver ops */
};

static struct modlinkage modlinkage = {
	MODREV_1, (void *)&modldrv, NULL
};

int
_init(void)
{
	int rval;
	/* CONSTCOND */
	ASSERT(NO_COMPETING_THREADS);

	rval = ddi_soft_state_init(&fas_state, sizeof (struct fas),
	    FAS_INITIAL_SOFT_SPACE);
	if (rval != 0) {
		return (rval);
	}

	if ((rval = scsi_hba_init(&modlinkage)) != 0) {
		ddi_soft_state_fini(&fas_state);
		return (rval);
	}

	mutex_init(&fas_global_mutex, NULL, MUTEX_DRIVER, NULL);
	rw_init(&fas_global_rwlock, NULL, RW_DRIVER, NULL);

	mutex_init(&fas_log_mutex, NULL, MUTEX_DRIVER, NULL);

	if ((rval = mod_install(&modlinkage)) != 0) {
		mutex_destroy(&fas_log_mutex);
		rw_destroy(&fas_global_rwlock);
		mutex_destroy(&fas_global_mutex);
		ddi_soft_state_fini(&fas_state);
		scsi_hba_fini(&modlinkage);
		return (rval);
	}

	return (rval);
}

int
_fini(void)
{
	int	rval;
	/* CONSTCOND */
	ASSERT(NO_COMPETING_THREADS);

	if ((rval = mod_remove(&modlinkage)) == 0) {
		ddi_soft_state_fini(&fas_state);
		scsi_hba_fini(&modlinkage);
		mutex_destroy(&fas_log_mutex);
		rw_destroy(&fas_global_rwlock);
		mutex_destroy(&fas_global_mutex);
	}
	return (rval);
}

int
_info(struct modinfo *modinfop)
{
	/* CONSTCOND */
	ASSERT(NO_COMPETING_THREADS);

	return (mod_info(&modlinkage, modinfop));
}

static int
fas_scsi_tgt_probe(struct scsi_device *sd,
    int (*waitfunc)(void))
{
	dev_info_t *dip = ddi_get_parent(sd->sd_dev);
	int rval = SCSIPROBE_FAILURE;
	scsi_hba_tran_t *tran;
	struct fas *fas;
	int tgt = sd->sd_address.a_target;

	tran = ddi_get_driver_private(dip);
	ASSERT(tran != NULL);
	fas = TRAN2FAS(tran);

	/*
	 * force renegotiation since inquiry cmds do not cause
	 * check conditions
	 */
	mutex_enter(FAS_MUTEX(fas));
	fas_force_renegotiation(fas, tgt);
	mutex_exit(FAS_MUTEX(fas));
	rval = scsi_hba_probe(sd, waitfunc);

	/*
	 * the scsi-options precedence is:
	 *	target-scsi-options		highest
	 * 	device-type-scsi-options
	 *	per bus scsi-options
	 *	global scsi-options		lowest
	 */
	mutex_enter(FAS_MUTEX(fas));
	if ((rval == SCSIPROBE_EXISTS) &&
	    ((fas->f_target_scsi_options_defined & (1 << tgt)) == 0)) {
		int options;

		options = scsi_get_device_type_scsi_options(dip, sd, -1);
		if (options != -1) {
			fas->f_target_scsi_options[tgt] = options;
			fas_log(fas, CE_NOTE,
			    "?target%x-scsi-options = 0x%x\n", tgt,
			    fas->f_target_scsi_options[tgt]);
			fas_force_renegotiation(fas, tgt);
		}
	}
	mutex_exit(FAS_MUTEX(fas));

	IPRINTF2("target%x-scsi-options= 0x%x\n",
	    tgt, fas->f_target_scsi_options[tgt]);

	return (rval);
}


/*ARGSUSED*/
static int
fas_scsi_tgt_init(dev_info_t *hba_dip, dev_info_t *tgt_dip,
    scsi_hba_tran_t *hba_tran, struct scsi_device *sd)
{
	return (((sd->sd_address.a_target < NTARGETS_WIDE) &&
	    (sd->sd_address.a_lun < NLUNS_PER_TARGET)) ?
	    DDI_SUCCESS : DDI_FAILURE);
}

/*ARGSUSED*/
static int
fas_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
{
	struct fas	*fas = NULL;
	volatile struct dma	*dmar = NULL;
	volatile struct fasreg	*fasreg;
	ddi_dma_attr_t		*fas_dma_attr;
	ddi_device_acc_attr_t	dev_attr;

	int			instance, id, slot, i, hm_rev;
	size_t			rlen;
	uint_t			count;
	char			buf[64];
	scsi_hba_tran_t		*tran =	NULL;
	char			intr_added = 0;
	char			mutex_init_done = 0;
	char			hba_attached = 0;
	char			bound_handle = 0;
	char			*prop_template = "target%d-scsi-options";
	char			prop_str[32];

	/* CONSTCOND */
	ASSERT(NO_COMPETING_THREADS);

	switch (cmd) {
	case DDI_ATTACH:
		break;

	case DDI_RESUME:
		if ((tran = ddi_get_driver_private(dip)) == NULL)
			return (DDI_FAILURE);

		fas = TRAN2FAS(tran);
		if (!fas) {
			return (DDI_FAILURE);
		}
		/*
		 * Reset hardware and softc to "no outstanding commands"
		 * Note that a check condition can result on first command
		 * to a target.
		 */
		mutex_enter(FAS_MUTEX(fas));
		fas_internal_reset(fas,
		    FAS_RESET_SOFTC|FAS_RESET_FAS|FAS_RESET_DMA);

		(void) fas_reset_bus(fas);

		fas->f_suspended = 0;

		/* make sure that things get started */
		(void) fas_istart(fas);
		fas_check_waitQ_and_mutex_exit(fas);

		mutex_enter(&fas_global_mutex);
		if (fas_timeout_id == 0) {
			fas_timeout_id = timeout(fas_watch, NULL, fas_tick);
			fas_timeout_initted = 1;
		}
		mutex_exit(&fas_global_mutex);

		return (DDI_SUCCESS);

	default:
		return (DDI_FAILURE);
	}

	instance = ddi_get_instance(dip);

	/*
	 * Since we know that some instantiations of this device can
	 * be plugged into slave-only SBus slots, check to see whether
	 * this is one such.
	 */
	if (ddi_slaveonly(dip) == DDI_SUCCESS) {
		cmn_err(CE_WARN,
		    "fas%d: device in slave-only slot", instance);
		return (DDI_FAILURE);
	}

	if (ddi_intr_hilevel(dip, 0)) {
		/*
		 * Interrupt number '0' is a high-level interrupt.
		 * At this point you either add a special interrupt
		 * handler that triggers a soft interrupt at a lower level,
		 * or - more simply and appropriately here - you just
		 * fail the attach.
		 */
		cmn_err(CE_WARN,
		    "fas%d: Device is using a hilevel intr", instance);
		return (DDI_FAILURE);
	}

	/*
	 * Allocate softc information.
	 */
	if (ddi_soft_state_zalloc(fas_state, instance) != DDI_SUCCESS) {
		cmn_err(CE_WARN,
		    "fas%d: cannot allocate soft state", instance);
		goto fail;
	}

	fas = (struct fas *)ddi_get_soft_state(fas_state, instance);

	if (fas == NULL) {
		goto fail;
	}

	/*
	 * map in device registers
	 */
	dev_attr.devacc_attr_version = DDI_DEVICE_ATTR_V0;
	dev_attr.devacc_attr_endian_flags = DDI_NEVERSWAP_ACC;
	dev_attr.devacc_attr_dataorder = DDI_STRICTORDER_ACC;

	if (ddi_regs_map_setup(dip, (uint_t)0, (caddr_t *)&dmar,
	    (off_t)0, (off_t)sizeof (struct dma),
	    &dev_attr, &fas->f_dmar_acc_handle) != DDI_SUCCESS) {
		cmn_err(CE_WARN, "fas%d: cannot map dma", instance);
		goto fail;
	}

	if (ddi_regs_map_setup(dip, (uint_t)1, (caddr_t *)&fasreg,
	    (off_t)0, (off_t)sizeof (struct fasreg),
	    &dev_attr, &fas->f_regs_acc_handle) != DDI_SUCCESS) {
		cmn_err(CE_WARN,
		    "fas%d: unable to map fas366 registers", instance);
		goto fail;
	}

	fas_dma_attr = &dma_fasattr;
	if (ddi_dma_alloc_handle(dip, fas_dma_attr,
	    DDI_DMA_SLEEP, NULL, &fas->f_dmahandle) != DDI_SUCCESS) {
		cmn_err(CE_WARN,
		    "fas%d: cannot alloc dma handle", instance);
		goto fail;
	}

	/*
	 * allocate cmdarea and its dma handle
	 */
	if (ddi_dma_mem_alloc(fas->f_dmahandle,
	    (uint_t)2*FIFOSIZE,
	    &dev_attr, DDI_DMA_CONSISTENT, DDI_DMA_SLEEP,
	    NULL, (caddr_t *)&fas->f_cmdarea, &rlen,
	    &fas->f_cmdarea_acc_handle) != DDI_SUCCESS) {
		cmn_err(CE_WARN,
		    "fas%d: cannot alloc cmd area", instance);
		goto fail;
	}

	fas->f_reg = fasreg;
	fas->f_dma = dmar;
	fas->f_instance  = instance;

	if (ddi_dma_addr_bind_handle(fas->f_dmahandle,
	    NULL, (caddr_t)fas->f_cmdarea,
	    rlen, DDI_DMA_RDWR|DDI_DMA_CONSISTENT, DDI_DMA_SLEEP, NULL,
	    &fas->f_dmacookie, &count) != DDI_DMA_MAPPED) {
		cmn_err(CE_WARN,
		    "fas%d: cannot bind cmdarea", instance);
		goto fail;
	}
	bound_handle++;

	ASSERT(count == 1);

	/*
	 * Allocate a transport structure
	 */
	tran = scsi_hba_tran_alloc(dip, SCSI_HBA_CANSLEEP);

	/* Indicate that we are 'sizeof (scsi_*(9S))' clean. */
	scsi_size_clean(dip);		/* SCSI_SIZE_CLEAN_VERIFY ok */

	/*
	 * initialize transport structure
	 */
	fas->f_tran			= tran;
	fas->f_dev			= dip;
	tran->tran_hba_private		= fas;
	tran->tran_tgt_private		= NULL;
	tran->tran_tgt_init		= fas_scsi_tgt_init;
	tran->tran_tgt_probe		= fas_scsi_tgt_probe;
	tran->tran_tgt_free		= NULL;
	tran->tran_start		= fas_scsi_start;
	tran->tran_abort		= fas_scsi_abort;
	tran->tran_reset		= fas_scsi_reset;
	tran->tran_getcap		= fas_scsi_getcap;
	tran->tran_setcap		= fas_scsi_setcap;
	tran->tran_init_pkt		= fas_scsi_init_pkt;
	tran->tran_destroy_pkt		= fas_scsi_destroy_pkt;
	tran->tran_dmafree		= fas_scsi_dmafree;
	tran->tran_sync_pkt		= fas_scsi_sync_pkt;
	tran->tran_reset_notify 	= fas_scsi_reset_notify;
	tran->tran_get_bus_addr		= NULL;
	tran->tran_get_name		= NULL;
	tran->tran_quiesce		= fas_scsi_quiesce;
	tran->tran_unquiesce		= fas_scsi_unquiesce;
	tran->tran_bus_reset		= NULL;
	tran->tran_add_eventcall	= NULL;
	tran->tran_get_eventcookie	= NULL;
	tran->tran_post_event		= NULL;
	tran->tran_remove_eventcall	= NULL;

	fas->f_force_async = 0;

	/*
	 * disable tagged queuing and wide for all targets
	 * (will be enabled by target driver if required)
	 * sync is enabled by default
	 */
	fas->f_nowide = fas->f_notag = ALL_TARGETS;
	fas->f_force_narrow = ALL_TARGETS;

	/*
	 * By default we assume embedded devices and save time
	 * checking for timeouts in fas_watch() by skipping
	 * the rest of luns
	 * If we're talking to any non-embedded devices,
	 * we can't cheat and skip over non-zero luns anymore
	 * in fas_watch() and fas_ustart().
	 */
	fas->f_dslot = NLUNS_PER_TARGET;

	/*
	 * f_active is used for saving disconnected cmds;
	 * For tagged targets, we need to increase the size later
	 * Only allocate for Lun == 0, if we probe a lun > 0 then
	 * we allocate an active structure
	 * If TQ gets enabled then we need to increase the size
	 * to hold 256 cmds
	 */
	for (slot = 0; slot < N_SLOTS; slot += NLUNS_PER_TARGET) {
		(void) fas_alloc_active_slots(fas, slot, KM_SLEEP);
	}

	/*
	 * initialize the qfull retry counts
	 */
	for (i = 0; i < NTARGETS_WIDE; i++) {
		fas->f_qfull_retries[i] = QFULL_RETRIES;
		fas->f_qfull_retry_interval[i] =
		    drv_usectohz(QFULL_RETRY_INTERVAL * 1000);

	}

	/*
	 * Initialize throttles.
	 */
	fas_set_throttles(fas, 0, N_SLOTS, MAX_THROTTLE);

	/*
	 * Initialize mask of deferred property updates
	 */
	fas->f_props_update = 0;

	/*
	 * set host ID
	 */
	fas->f_fasconf = DEFAULT_HOSTID;
	id = ddi_prop_get_int(DDI_DEV_T_ANY, dip, 0, "initiator-id", -1);
	if (id == -1) {
		id = ddi_prop_get_int(DDI_DEV_T_ANY,	dip, 0,
		    "scsi-initiator-id", -1);
	}
	if (id != DEFAULT_HOSTID && id >= 0 && id < NTARGETS_WIDE) {
		fas_log(fas, CE_NOTE, "?initiator SCSI ID now %d\n", id);
		fas->f_fasconf = (uchar_t)id;
	}

	/*
	 * find the burstsize and reduce ours if necessary
	 */
	fas->f_dma_attr = fas_dma_attr;
	fas->f_dma_attr->dma_attr_burstsizes &=
	    ddi_dma_burstsizes(fas->f_dmahandle);

#ifdef FASDEBUG
	fas->f_dma_attr->dma_attr_burstsizes &= fas_burstsizes_limit;
	IPRINTF1("dma burstsize=%x\n", fas->f_dma_attr->dma_attr_burstsizes);
#endif
	/*
	 * Attach this instance of the hba
	 */
	if (scsi_hba_attach_setup(dip, fas->f_dma_attr, tran, 0) !=
	    DDI_SUCCESS) {
		fas_log(fas, CE_WARN, "scsi_hba_attach_setup failed");
		goto fail;
	}
	hba_attached++;

	/*
	 * if scsi-options property exists, use it
	 */
	fas->f_scsi_options = ddi_prop_get_int(DDI_DEV_T_ANY,
	    dip, 0, "scsi-options", DEFAULT_SCSI_OPTIONS);

	/*
	 * if scsi-selection-timeout property exists, use it
	 */
	fas_selection_timeout = ddi_prop_get_int(DDI_DEV_T_ANY,
	    dip, 0, "scsi-selection-timeout", SCSI_DEFAULT_SELECTION_TIMEOUT);

	/*
	 * if hm-rev property doesn't exist, use old scheme for rev
	 */
	hm_rev = ddi_prop_get_int(DDI_DEV_T_ANY, dip, 0,
	    "hm-rev", -1);

	if (hm_rev == 0xa0 || hm_rev == -1) {
		if (DMAREV(dmar) != 0) {
			fas->f_hm_rev = 0x20;
			fas_log(fas, CE_WARN,
			    "obsolete rev 2.0 FEPS chip, "
			    "possible data corruption");
		} else {
			fas->f_hm_rev = 0x10;
			fas_log(fas, CE_WARN,
			    "obsolete and unsupported rev 1.0 FEPS chip");
			goto fail;
		}
	} else if (hm_rev == 0x20) {
		fas->f_hm_rev = 0x21;
		fas_log(fas, CE_WARN, "obsolete rev 2.1 FEPS chip");
	} else {
		fas->f_hm_rev = (uchar_t)hm_rev;
		fas_log(fas, CE_NOTE, "?rev %x.%x FEPS chip\n",
		    (hm_rev >> 4) & 0xf, hm_rev & 0xf);
	}

	if ((fas->f_scsi_options & SCSI_OPTIONS_SYNC) == 0) {
		fas->f_nosync = ALL_TARGETS;
	}

	if ((fas->f_scsi_options & SCSI_OPTIONS_WIDE) == 0) {
		fas->f_nowide = ALL_TARGETS;
	}

	/*
	 * if target<n>-scsi-options property exists, use it;
	 * otherwise use the f_scsi_options
	 */
	for (i = 0; i < NTARGETS_WIDE; i++) {
		(void) sprintf(prop_str, prop_template, i);
		fas->f_target_scsi_options[i] = ddi_prop_get_int(
		    DDI_DEV_T_ANY, dip, 0, prop_str, -1);

		if (fas->f_target_scsi_options[i] != -1) {
			fas_log(fas, CE_NOTE, "?target%x-scsi-options=0x%x\n",
			    i, fas->f_target_scsi_options[i]);
			fas->f_target_scsi_options_defined |= 1 << i;
		} else {
			fas->f_target_scsi_options[i] = fas->f_scsi_options;
		}
		if (((fas->f_target_scsi_options[i] &
		    SCSI_OPTIONS_DR) == 0) &&
		    (fas->f_target_scsi_options[i] & SCSI_OPTIONS_TAG)) {
			fas->f_target_scsi_options[i] &= ~SCSI_OPTIONS_TAG;
			fas_log(fas, CE_WARN,
			    "Disabled TQ since disconnects are disabled");
		}
	}

	fas->f_scsi_tag_age_limit =
	    ddi_prop_get_int(DDI_DEV_T_ANY, dip, 0, "scsi-tag-age-limit",
	    DEFAULT_TAG_AGE_LIMIT);

	fas->f_scsi_reset_delay = ddi_prop_get_int(DDI_DEV_T_ANY,
	    dip, 0, "scsi-reset-delay", SCSI_DEFAULT_RESET_DELAY);
	if (fas->f_scsi_reset_delay == 0) {
		fas_log(fas, CE_NOTE,
		    "scsi_reset_delay of 0 is not recommended,"
		    " resetting to SCSI_DEFAULT_RESET_DELAY\n");
		fas->f_scsi_reset_delay = SCSI_DEFAULT_RESET_DELAY;
	}

	/*
	 * get iblock cookie and initialize mutexes
	 */
	if (ddi_get_iblock_cookie(dip, (uint_t)0, &fas->f_iblock)
	    != DDI_SUCCESS) {
		cmn_err(CE_WARN, "fas_attach: cannot get iblock cookie");
		goto fail;
	}

	mutex_init(&fas->f_mutex, NULL, MUTEX_DRIVER, fas->f_iblock);
	cv_init(&fas->f_cv, NULL, CV_DRIVER, NULL);

	/*
	 * initialize mutex for waitQ
	 */
	mutex_init(&fas->f_waitQ_mutex, NULL, MUTEX_DRIVER, fas->f_iblock);
	mutex_init_done++;

	/*
	 * initialize callback mechanism (immediate callback)
	 */
	mutex_enter(&fas_global_mutex);
	if (fas_init_callbacks(fas)) {
		mutex_exit(&fas_global_mutex);
		goto fail;
	}
	mutex_exit(&fas_global_mutex);

	/*
	 * kstat_intr support
	 */
	(void) sprintf(buf, "fas%d", instance);
	fas->f_intr_kstat = kstat_create("fas", instance, buf, "controller", \
	    KSTAT_TYPE_INTR, 1, KSTAT_FLAG_PERSISTENT);
	if (fas->f_intr_kstat)
		kstat_install(fas->f_intr_kstat);

	/*
	 * install interrupt handler
	 */
	mutex_enter(FAS_MUTEX(fas));
	if (ddi_add_intr(dip, (uint_t)0, &fas->f_iblock, NULL,
	    fas_intr, (caddr_t)fas)) {
		cmn_err(CE_WARN, "fas: cannot add intr");
		mutex_exit(FAS_MUTEX(fas));
		goto fail;
	}
	intr_added++;

	/*
	 * initialize fas chip
	 */
	if (fas_init_chip(fas, id))	{
		cmn_err(CE_WARN, "fas: cannot initialize");
		mutex_exit(FAS_MUTEX(fas));
		goto fail;
	}
	mutex_exit(FAS_MUTEX(fas));

	/*
	 * create kmem cache for packets
	 */
	(void) sprintf(buf, "fas%d_cache", instance);
	fas->f_kmem_cache = kmem_cache_create(buf,
	    EXTCMD_SIZE, 8,
	    fas_kmem_cache_constructor, fas_kmem_cache_destructor,
	    NULL, (void *)fas, NULL, 0);
	if (fas->f_kmem_cache == NULL) {
		cmn_err(CE_WARN, "fas: cannot create kmem_cache");
		goto fail;
	}

	/*
	 * at this point, we are not going to fail the attach
	 * so there is no need to undo the rest:
	 *
	 * add this fas to the list, this makes debugging easier
	 * and fas_watch() needs it to walk thru all fas's
	 */
	rw_enter(&fas_global_rwlock, RW_WRITER);
	if (fas_head == NULL) {
		fas_head = fas;
	} else {
		fas_tail->f_next = fas;
	}
	fas_tail = fas; 	/* point to last fas in list */
	rw_exit(&fas_global_rwlock);

	/*
	 * there is one watchdog handler for all driver instances.
	 * start the watchdog if it hasn't been done yet
	 */
	mutex_enter(&fas_global_mutex);
	if (fas_scsi_watchdog_tick == 0) {
		fas_scsi_watchdog_tick = ddi_prop_get_int(DDI_DEV_T_ANY,
		    dip, 0, "scsi-watchdog-tick", DEFAULT_WD_TICK);
		if (fas_scsi_watchdog_tick != DEFAULT_WD_TICK) {
			fas_log(fas, CE_NOTE, "?scsi-watchdog-tick=%d\n",
			    fas_scsi_watchdog_tick);
		}
		fas_tick = drv_usectohz((clock_t)
		    fas_scsi_watchdog_tick * 1000000);
		IPRINTF2("fas scsi watchdog tick=%x, fas_tick=%lx\n",
		    fas_scsi_watchdog_tick, fas_tick);
		if (fas_timeout_id == 0) {
			fas_timeout_id = timeout(fas_watch, NULL, fas_tick);
			fas_timeout_initted = 1;
		}
	}
	mutex_exit(&fas_global_mutex);

	ddi_report_dev(dip);

	return (DDI_SUCCESS);

fail:
	cmn_err(CE_WARN, "fas%d: cannot attach", instance);
	if (fas) {
		for (slot = 0; slot < N_SLOTS; slot++) {
			struct f_slots *active = fas->f_active[slot];
			if (active) {
				kmem_free(active, active->f_size);
				fas->f_active[slot] = NULL;
			}
		}
		if (mutex_init_done) {
			mutex_destroy(&fas->f_mutex);
			mutex_destroy(&fas->f_waitQ_mutex);
			cv_destroy(&fas->f_cv);
		}
		if (intr_added) {
			ddi_remove_intr(dip, (uint_t)0, fas->f_iblock);
		}
		/*
		 * kstat_intr support
		 */
		if (fas->f_intr_kstat) {
			kstat_delete(fas->f_intr_kstat);
		}
		if (hba_attached) {
			(void) scsi_hba_detach(dip);
		}
		if (tran) {
			scsi_hba_tran_free(tran);
		}
		if (fas->f_kmem_cache) {
			kmem_cache_destroy(fas->f_kmem_cache);
		}
		if (fas->f_cmdarea) {
			if (bound_handle) {
				(void) ddi_dma_unbind_handle(fas->f_dmahandle);
			}
			ddi_dma_mem_free(&fas->f_cmdarea_acc_handle);
		}
		if (fas->f_dmahandle) {
			ddi_dma_free_handle(&fas->f_dmahandle);
		}
		fas_destroy_callbacks(fas);
		if (fas->f_regs_acc_handle) {
			ddi_regs_map_free(&fas->f_regs_acc_handle);
		}
		if (fas->f_dmar_acc_handle) {
			ddi_regs_map_free(&fas->f_dmar_acc_handle);
		}
		ddi_soft_state_free(fas_state, instance);

		ddi_remove_minor_node(dip, NULL);
	}
	return (DDI_FAILURE);
}

/*ARGSUSED*/
static int
fas_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
{
	struct fas	*fas, *nfas;
	scsi_hba_tran_t 	*tran;

	/* CONSTCOND */
	ASSERT(NO_COMPETING_THREADS);

	switch (cmd) {
	case DDI_DETACH:
		return (fas_dr_detach(dip));

	case DDI_SUSPEND:
		if ((tran = ddi_get_driver_private(dip)) == NULL)
			return (DDI_FAILURE);

		fas = TRAN2FAS(tran);
		if (!fas) {
			return (DDI_FAILURE);
		}

		mutex_enter(FAS_MUTEX(fas));

		fas->f_suspended = 1;

		if (fas->f_ncmds) {
			(void) fas_reset_bus(fas);
			(void) fas_dopoll(fas, SHORT_POLL_TIMEOUT);
		}
		/*
		 * disable dma and fas interrupt
		 */
		fas->f_dma_csr &= ~DMA_INTEN;
		fas->f_dma_csr &= ~DMA_ENDVMA;
		fas_dma_reg_write(fas, &fas->f_dma->dma_csr, fas->f_dma_csr);

		mutex_exit(FAS_MUTEX(fas));

		if (fas->f_quiesce_timeid) {
			(void) untimeout(fas->f_quiesce_timeid);
				fas->f_quiesce_timeid = 0;
		}

		if (fas->f_restart_cmd_timeid) {
			(void) untimeout(fas->f_restart_cmd_timeid);
				fas->f_restart_cmd_timeid = 0;
		}

		/* Last fas? */
		rw_enter(&fas_global_rwlock, RW_WRITER);
		for (nfas = fas_head; nfas; nfas = nfas->f_next) {
			if (!nfas->f_suspended) {
				rw_exit(&fas_global_rwlock);
				return (DDI_SUCCESS);
			}
		}
		rw_exit(&fas_global_rwlock);

		mutex_enter(&fas_global_mutex);
		if (fas_timeout_id != 0) {
			timeout_id_t tid = fas_timeout_id;
			fas_timeout_id = 0;
			fas_timeout_initted = 0;
			mutex_exit(&fas_global_mutex);
			(void) untimeout(tid);
		} else {
			mutex_exit(&fas_global_mutex);
		}

		mutex_enter(&fas_global_mutex);
		if (fas_reset_watch) {
			timeout_id_t tid = fas_reset_watch;
			fas_reset_watch = 0;
			mutex_exit(&fas_global_mutex);
			(void) untimeout(tid);
		} else {
			mutex_exit(&fas_global_mutex);
		}

		return (DDI_SUCCESS);

	default:
		return (DDI_FAILURE);
	}
	_NOTE(NOT_REACHED)
	/* NOTREACHED */
}

static int
fas_dr_detach(dev_info_t *dip)
{
	struct fas 	*fas, *f;
	scsi_hba_tran_t		*tran;
	short		slot;
	int			i, j;

	if ((tran = ddi_get_driver_private(dip)) == NULL)
		return (DDI_FAILURE);

	fas = TRAN2FAS(tran);
	if (!fas) {
		return (DDI_FAILURE);
	}

	/*
	 * disable interrupts
	 */
	fas->f_dma_csr &= ~DMA_INTEN;
	fas->f_dma->dma_csr = fas->f_dma_csr;
	ddi_remove_intr(dip, (uint_t)0, fas->f_iblock);

	/*
	 * Remove device instance from the global linked list
	 */
	rw_enter(&fas_global_rwlock, RW_WRITER);

	if (fas_head == fas) {
		f = fas_head = fas->f_next;
	} else {
		for (f = fas_head; f != (struct fas *)NULL; f = f->f_next) {
			if (f->f_next == fas) {
				f->f_next = fas->f_next;
				break;
			}
		}

		/*
		 * Instance not in softc list. Since the
		 * instance is not there in softc list, don't
		 * enable interrupts, the instance is effectively
		 * unusable.
		 */
		if (f == (struct fas *)NULL) {
			cmn_err(CE_WARN, "fas_dr_detach: fas instance not"
			    " in softc list!");
			rw_exit(&fas_global_rwlock);
			return (DDI_FAILURE);
		}


	}

	if (fas_tail == fas)
		fas_tail = f;

	rw_exit(&fas_global_rwlock);

	if (fas->f_intr_kstat)
		kstat_delete(fas->f_intr_kstat);

	fas_destroy_callbacks(fas);

	scsi_hba_reset_notify_tear_down(fas->f_reset_notify_listf);

	mutex_enter(&fas_global_mutex);
	/*
	 * destroy any outstanding tagged command info
	 */
	for (slot = 0; slot < N_SLOTS; slot++) {
		struct f_slots *active = fas->f_active[slot];
		if (active) {
			ushort_t	tag;
			for (tag = 0; tag < active->f_n_slots; tag++) {
				struct fas_cmd	*sp = active->f_slot[tag];
				if (sp) {
					struct scsi_pkt *pkt = sp->cmd_pkt;
					if (pkt) {
						(void) fas_scsi_destroy_pkt(
						    &pkt->pkt_address, pkt);
					}
					/* sp freed in fas_scsi_destroy_pkt */
					active->f_slot[tag] = NULL;
				}
			}
			kmem_free(active, active->f_size);
			fas->f_active[slot] = NULL;
		}
		ASSERT(fas->f_tcmds[slot] == 0);
	}

	/*
	 * disallow timeout thread rescheduling
	 */
	fas->f_flags |= FAS_FLG_NOTIMEOUTS;
	mutex_exit(&fas_global_mutex);

	if (fas->f_quiesce_timeid) {
		(void) untimeout(fas->f_quiesce_timeid);
	}

	/*
	 * last fas? ... if active, CANCEL watch threads.
	 */
	mutex_enter(&fas_global_mutex);
	if (fas_head == (struct fas *)NULL) {
		if (fas_timeout_initted) {
			timeout_id_t tid = fas_timeout_id;
			fas_timeout_initted = 0;
			fas_timeout_id = 0;		/* don't resched */
			mutex_exit(&fas_global_mutex);
			(void) untimeout(tid);
			mutex_enter(&fas_global_mutex);
		}

		if (fas_reset_watch) {
			mutex_exit(&fas_global_mutex);
			(void) untimeout(fas_reset_watch);
			mutex_enter(&fas_global_mutex);
			fas_reset_watch = 0;
		}
	}
	mutex_exit(&fas_global_mutex);

	if (fas->f_restart_cmd_timeid) {
		(void) untimeout(fas->f_restart_cmd_timeid);
		fas->f_restart_cmd_timeid = 0;
	}

	/*
	 * destroy outstanding ARQ pkts
	 */
	for (i = 0; i < NTARGETS_WIDE; i++) {
		for (j = 0; j < NLUNS_PER_TARGET; j++) {
			int slot = i * NLUNS_PER_TARGET | j;
			if (fas->f_arq_pkt[slot]) {
				struct scsi_address	sa;
				sa.a_hba_tran = NULL;		/* not used */
				sa.a_target = (ushort_t)i;
				sa.a_lun = (uchar_t)j;
				(void) fas_delete_arq_pkt(fas, &sa);
			}
		}
	}

	/*
	 * Remove device MT locks and CV
	 */
	mutex_destroy(&fas->f_waitQ_mutex);
	mutex_destroy(&fas->f_mutex);
	cv_destroy(&fas->f_cv);

	/*
	 * Release miscellaneous device resources
	 */

	if (fas->f_kmem_cache) {
		kmem_cache_destroy(fas->f_kmem_cache);
	}

	if (fas->f_cmdarea != (uchar_t *)NULL) {
		(void) ddi_dma_unbind_handle(fas->f_dmahandle);
		ddi_dma_mem_free(&fas->f_cmdarea_acc_handle);
	}

	if (fas->f_dmahandle != (ddi_dma_handle_t)NULL) {
		ddi_dma_free_handle(&fas->f_dmahandle);
	}

	if (fas->f_regs_acc_handle) {
		ddi_regs_map_free(&fas->f_regs_acc_handle);
	}
	if (fas->f_dmar_acc_handle) {
		ddi_regs_map_free(&fas->f_dmar_acc_handle);
	}

	/*
	 * Remove properties created during attach()
	 */
	ddi_prop_remove_all(dip);

	/*
	 * Delete the DMA limits, transport vectors and remove the device
	 * links to the scsi_transport layer.
	 *	-- ddi_set_driver_private(dip, NULL)
	 */
	(void) scsi_hba_detach(dip);

	/*
	 * Free the scsi_transport structure for this device.
	 */
	scsi_hba_tran_free(tran);

	ddi_soft_state_free(fas_state, ddi_get_instance(dip));

	return (DDI_SUCCESS);
}

static int
fas_quiesce_bus(struct fas *fas)
{
	mutex_enter(FAS_MUTEX(fas));
	IPRINTF("fas_quiesce: QUIESCEing\n");
	IPRINTF3("fas_quiesce: ncmds (%d) ndisc (%d) state (%d)\n",
	    fas->f_ncmds, fas->f_ndisc, fas->f_softstate);
	fas_set_throttles(fas, 0, N_SLOTS, HOLD_THROTTLE);
	if (fas_check_outstanding(fas)) {
		fas->f_softstate |= FAS_SS_DRAINING;
		fas->f_quiesce_timeid = timeout(fas_ncmds_checkdrain,
		    fas, (FAS_QUIESCE_TIMEOUT * drv_usectohz(1000000)));
		if (cv_wait_sig(FAS_CV(fas), FAS_MUTEX(fas)) == 0) {
			/*
			 * quiesce has been interrupted.
			 */
			IPRINTF("fas_quiesce: abort QUIESCE\n");
			fas->f_softstate &= ~FAS_SS_DRAINING;
			fas_set_throttles(fas, 0, N_SLOTS, MAX_THROTTLE);
			(void) fas_istart(fas);
			if (fas->f_quiesce_timeid != 0) {
				mutex_exit(FAS_MUTEX(fas));
#ifndef __lock_lint	/* warlock complains but there is a NOTE on this */
				(void) untimeout(fas->f_quiesce_timeid);
				fas->f_quiesce_timeid = 0;
#endif
				return (-1);
			}
			mutex_exit(FAS_MUTEX(fas));
			return (-1);
		} else {
			IPRINTF("fas_quiesce: bus is QUIESCED\n");
			ASSERT(fas->f_quiesce_timeid == 0);
			fas->f_softstate &= ~FAS_SS_DRAINING;
			fas->f_softstate |= FAS_SS_QUIESCED;
			mutex_exit(FAS_MUTEX(fas));
			return (0);
		}
	}
	IPRINTF("fas_quiesce: bus was not busy QUIESCED\n");
	mutex_exit(FAS_MUTEX(fas));
	return (0);
}

static int
fas_unquiesce_bus(struct fas *fas)
{
	mutex_enter(FAS_MUTEX(fas));
	fas->f_softstate &= ~FAS_SS_QUIESCED;
	fas_set_throttles(fas, 0, N_SLOTS, MAX_THROTTLE);
	(void) fas_istart(fas);
	IPRINTF("fas_quiesce: bus has been UNQUIESCED\n");
	mutex_exit(FAS_MUTEX(fas));

	return (0);
}

/*
 * invoked from timeout() to check the number of outstanding commands
 */
static void
fas_ncmds_checkdrain(void *arg)
{
	struct fas *fas = arg;

	mutex_enter(FAS_MUTEX(fas));
	IPRINTF3("fas_checkdrain: ncmds (%d) ndisc (%d) state (%d)\n",
	    fas->f_ncmds, fas->f_ndisc, fas->f_softstate);
	if (fas->f_softstate & FAS_SS_DRAINING) {
		fas->f_quiesce_timeid = 0;
		if (fas_check_outstanding(fas) == 0) {
			IPRINTF("fas_drain: bus has drained\n");
			cv_signal(FAS_CV(fas));
		} else {
			/*
			 * throttle may have been reset by a bus reset
			 * or fas_runpoll()
			 * XXX shouldn't be necessary
			 */
			fas_set_throttles(fas, 0, N_SLOTS, HOLD_THROTTLE);
			IPRINTF("fas_drain: rescheduling timeout\n");
			fas->f_quiesce_timeid = timeout(fas_ncmds_checkdrain,
			    fas, (FAS_QUIESCE_TIMEOUT * drv_usectohz(1000000)));
		}
	}
	mutex_exit(FAS_MUTEX(fas));
}

static int
fas_check_outstanding(struct fas *fas)
{
	uint_t slot;
	uint_t d = ((fas->f_dslot == 0)? 1 : fas->f_dslot);
	int ncmds = 0;

	ASSERT(mutex_owned(FAS_MUTEX(fas)));

	for (slot = 0; slot < N_SLOTS; slot += d)
		ncmds += fas->f_tcmds[slot];

	return (ncmds);
}


#ifdef	FASDEBUG
/*
 * fas register read/write functions with tracing
 */
static void
fas_reg_tracing(struct fas *fas, int type, int regno, uint32_t what)
{
	fas->f_reg_trace[fas->f_reg_trace_index++] = type;
	fas->f_reg_trace[fas->f_reg_trace_index++] = regno;
	fas->f_reg_trace[fas->f_reg_trace_index++] = what;
	fas->f_reg_trace[fas->f_reg_trace_index++] = gethrtime();
	fas->f_reg_trace[fas->f_reg_trace_index] = 0xff;
	if (fas->f_reg_trace_index >= REG_TRACE_BUF_SIZE) {
		fas->f_reg_trace_index = 0;
	}
}

static void
fas_reg_cmd_write(struct fas *fas, uint8_t cmd)
{
	volatile struct fasreg *fasreg = fas->f_reg;
	int regno = (uintptr_t)&fasreg->fas_cmd - (uintptr_t)fasreg;

	fasreg->fas_cmd = cmd;
	fas->f_last_cmd = cmd;

	EPRINTF1("issuing cmd %x\n", (uchar_t)cmd);
	fas_reg_tracing(fas, 0, regno, cmd);

	fas->f_reg_cmds++;
}

static void
fas_reg_write(struct fas *fas, volatile uint8_t *p, uint8_t what)
{
	int regno = (uintptr_t)p - (uintptr_t)fas->f_reg;

	*p = what;

	EPRINTF2("writing reg%x = %x\n", regno, what);
	fas_reg_tracing(fas, 1, regno, what);

	fas->f_reg_writes++;
}

static uint8_t
fas_reg_read(struct fas *fas, volatile uint8_t *p)
{
	uint8_t what;
	int regno = (uintptr_t)p - (uintptr_t)fas->f_reg;

	what = *p;

	EPRINTF2("reading reg%x => %x\n", regno, what);
	fas_reg_tracing(fas, 2, regno, what);

	fas->f_reg_reads++;

	return (what);
}

/*
 * dma register access routines
 */
static void
fas_dma_reg_write(struct fas *fas, volatile uint32_t *p, uint32_t what)
{
	*p = what;
	fas->f_reg_dma_writes++;

#ifdef DMA_REG_TRACING
{
	int regno = (uintptr_t)p - (uintptr_t)fas->f_dma;
	EPRINTF2("writing dma reg%x = %x\n", regno, what);
	fas_reg_tracing(fas, 3, regno, what);
}
#endif
}

static uint32_t
fas_dma_reg_read(struct fas *fas, volatile uint32_t *p)
{
	uint32_t what = *p;
	fas->f_reg_dma_reads++;

#ifdef DMA_REG_TRACING
{
	int regno = (uintptr_t)p - (uintptr_t)fas->f_dma;
	EPRINTF2("reading dma reg%x => %x\n", regno, what);
	fas_reg_tracing(fas, 4, regno, what);
}
#endif
	return (what);
}
#endif

#define	FIFO_EMPTY(fas)  (fas_reg_read(fas, &fas->f_reg->fas_stat2) & \
		FAS_STAT2_EMPTY)
#define	FIFO_CNT(fas) \
	(fas_reg_read(fas, &fas->f_reg->fas_fifo_flag) & FIFO_CNT_MASK)

#ifdef FASDEBUG
static void
fas_assert_atn(struct fas *fas)
{
	fas_reg_cmd_write(fas, CMD_SET_ATN);
#ifdef FAS_TEST
	if (fas_test_stop > 1)
		debug_enter("asserted atn");
#endif
}
#else
#define	fas_assert_atn(fas)  fas_reg_cmd_write(fas, CMD_SET_ATN)
#endif

/*
 * DMA macros; we use a shadow copy of the dma_csr to	save unnecessary
 * reads
 */
#define	FAS_DMA_WRITE(fas, count, base, cmd) { \
	volatile struct fasreg *fasreg = fas->f_reg; \
	volatile struct dma *dmar = fas->f_dma; \
	ASSERT((fas_dma_reg_read(fas, &dmar->dma_csr) & DMA_ENDVMA) == 0); \
	SET_FAS_COUNT(fasreg, count); \
	fas_reg_cmd_write(fas, cmd); \
	fas_dma_reg_write(fas, &dmar->dma_count, count); \
	fas->f_dma_csr |= \
	    DMA_WRITE | DMA_ENDVMA | DMA_DSBL_DRAIN; \
	fas_dma_reg_write(fas, &dmar->dma_addr, (fas->f_lastdma = base)); \
	fas_dma_reg_write(fas, &dmar->dma_csr, fas->f_dma_csr); \
}

#define	FAS_DMA_WRITE_SETUP(fas, count, base) { \
	volatile struct fasreg *fasreg = fas->f_reg; \
	volatile struct dma *dmar = fas->f_dma; \
	ASSERT((fas_dma_reg_read(fas, &dmar->dma_csr) & DMA_ENDVMA) == 0); \
	SET_FAS_COUNT(fasreg, count); \
	fas_dma_reg_write(fas, &dmar->dma_count, count); \
	fas->f_dma_csr |= \
	    DMA_WRITE | DMA_ENDVMA | DMA_DSBL_DRAIN; \
	fas_dma_reg_write(fas, &dmar->dma_addr, (fas->f_lastdma = base)); \
}


#define	FAS_DMA_READ(fas, count, base, dmacount, cmd) { \
	volatile struct fasreg *fasreg = fas->f_reg; \
	volatile struct dma *dmar = fas->f_dma; \
	ASSERT((fas_dma_reg_read(fas, &dmar->dma_csr) & DMA_ENDVMA) == 0); \
	SET_FAS_COUNT(fasreg, count); \
	fas_reg_cmd_write(fas, cmd); \
	fas->f_dma_csr |= \
	    (fas->f_dma_csr &	~DMA_WRITE) | DMA_ENDVMA | DMA_DSBL_DRAIN; \
	fas_dma_reg_write(fas, &dmar->dma_count, dmacount); \
	fas_dma_reg_write(fas, &dmar->dma_addr, (fas->f_lastdma = base)); \
	fas_dma_reg_write(fas, &dmar->dma_csr, fas->f_dma_csr); \
}

static void
FAS_FLUSH_DMA(struct fas *fas)
{
	fas_dma_reg_write(fas, &fas->f_dma->dma_csr, DMA_RESET);
	fas->f_dma_csr |= (DMA_INTEN|DMA_TWO_CYCLE|DMA_DSBL_PARITY|
	    DMA_DSBL_DRAIN);
	fas->f_dma_csr &= ~(DMA_ENDVMA | DMA_WRITE);
	fas_dma_reg_write(fas, &fas->f_dma->dma_csr, 0);
	fas_dma_reg_write(fas, &fas->f_dma->dma_csr, fas->f_dma_csr);
	fas_dma_reg_write(fas, &fas->f_dma->dma_addr, 0);
}

/*
 * FAS_FLUSH_DMA_HARD checks on REQPEND before taking away the reset
 */
static void
FAS_FLUSH_DMA_HARD(struct fas *fas)
{
	fas_dma_reg_write(fas, &fas->f_dma->dma_csr, DMA_RESET);
	fas->f_dma_csr |= (DMA_INTEN|DMA_TWO_CYCLE|DMA_DSBL_PARITY|
	    DMA_DSBL_DRAIN);
	fas->f_dma_csr &= ~(DMA_ENDVMA | DMA_WRITE);
	while (fas_dma_reg_read(fas, &fas->f_dma->dma_csr) & DMA_REQPEND)
		;
	fas_dma_reg_write(fas, &fas->f_dma->dma_csr, 0);
	fas_dma_reg_write(fas, &fas->f_dma->dma_csr, fas->f_dma_csr);
	fas_dma_reg_write(fas, &fas->f_dma->dma_addr, 0);
}

/*
 * update period, conf3, offset reg, if necessary
 */
#define	FAS_SET_PERIOD_OFFSET_CONF3_REGS(fas, target) \
{ \
	uchar_t period, offset, conf3; \
	period = fas->f_sync_period[target] & SYNC_PERIOD_MASK; \
	offset = fas->f_offset[target]; \
	conf3  = fas->f_fasconf3[target]; \
	if ((period != fas->f_period_reg_last) || \
	    (offset != fas->f_offset_reg_last) || \
	    (conf3 != fas->f_fasconf3_reg_last)) { \
		fas->f_period_reg_last = period; \
		fas->f_offset_reg_last = offset; \
		fas->f_fasconf3_reg_last = conf3; \
		fas_reg_write(fas, &fasreg->fas_sync_period, period); \
		fas_reg_write(fas, &fasreg->fas_sync_offset, offset); \
		fas_reg_write(fas, &fasreg->fas_conf3, conf3); \
	} \
}

/*
 * fifo read/write routines
 * always read the fifo bytes before reading the interrupt register
 */

static void
fas_read_fifo(struct fas *fas)
{
	int stat = fas->f_stat;
	volatile struct fasreg	 *fasreg = fas->f_reg;
	int		 i;

	i = fas_reg_read(fas, &fasreg->fas_fifo_flag) & FIFO_CNT_MASK;
	EPRINTF2("fas_read_fifo: fifo cnt=%x, stat=%x\n", i, stat);
	ASSERT(i <= FIFOSIZE);

	fas->f_fifolen = 0;
	while (i-- > 0) {
		fas->f_fifo[fas->f_fifolen++] = fas_reg_read(fas,
		    &fasreg->fas_fifo_data);
		fas->f_fifo[fas->f_fifolen++] = fas_reg_read(fas,
		    &fasreg->fas_fifo_data);
	}
	if (fas->f_stat2 & FAS_STAT2_ISHUTTLE)	{

		/* write pad byte */
		fas_reg_write(fas, &fasreg->fas_fifo_data, 0);
		fas->f_fifo[fas->f_fifolen++] = fas_reg_read(fas,
		    &fasreg->fas_fifo_data);
		/* flush pad byte */
		fas_reg_cmd_write(fas, CMD_FLUSH);
	}
	EPRINTF2("fas_read_fifo: fifo len=%x, stat2=%x\n",
	    fas->f_fifolen, stat);
} /* fas_read_fifo */

static void
fas_write_fifo(struct fas *fas, uchar_t *buf, int length, int pad)
{
	int i;
	volatile struct fasreg	 *fasreg = fas->f_reg;

	EPRINTF1("writing fifo %x bytes\n", length);
	ASSERT(length <= 15);
	fas_reg_cmd_write(fas, CMD_FLUSH);
	for (i = 0; i < length; i++) {
		fas_reg_write(fas, &fasreg->fas_fifo_data, buf[i]);
		if (pad) {
			fas_reg_write(fas, &fasreg->fas_fifo_data, 0);
		}
	}
}

/*
 * Hardware and Software internal reset routines
 */
static int
fas_init_chip(struct fas *fas, uchar_t initiator_id)
{
	int		i;
	uchar_t		clock_conv;
	uchar_t		initial_conf3;
	uint_t		ticks;
	static char	*prop_cfreq = "clock-frequency";

	/*
	 * Determine clock frequency of attached FAS chip.
	 */
	i = ddi_prop_get_int(DDI_DEV_T_ANY,
	    fas->f_dev, DDI_PROP_DONTPASS, prop_cfreq, -1);
	clock_conv = (i + FIVE_MEG - 1) / FIVE_MEG;
	if (clock_conv != CLOCK_40MHZ) {
		fas_log(fas, CE_WARN, "Bad clock frequency");
		return (-1);
	}

	fas->f_clock_conv = clock_conv;
	fas->f_clock_cycle = CLOCK_PERIOD(i);
	ticks = FAS_CLOCK_TICK(fas);
	fas->f_stval = FAS_CLOCK_TIMEOUT(ticks, fas_selection_timeout);

	DPRINTF5("%d mhz, clock_conv %d, clock_cycle %d, ticks %d, stval %d\n",
	    i, fas->f_clock_conv, fas->f_clock_cycle,
	    ticks, fas->f_stval);
	/*
	 * set up conf registers
	 */
	fas->f_fasconf |= FAS_CONF_PAREN;
	fas->f_fasconf2 = (uchar_t)(FAS_CONF2_FENABLE | FAS_CONF2_XL32);

	if (initiator_id < NTARGETS) {
		initial_conf3 = FAS_CONF3_FASTCLK | FAS_CONF3_ODDBYTE_AUTO;
	} else {
		initial_conf3 = FAS_CONF3_FASTCLK | FAS_CONF3_ODDBYTE_AUTO |
		    FAS_CONF3_IDBIT3;
	}

	for (i = 0; i < NTARGETS_WIDE; i++) {
		fas->f_fasconf3[i] = initial_conf3;
	}

	/*
	 * Avoid resetting the scsi bus since this causes a few seconds
	 * delay per fas in boot and also causes busy conditions in some
	 * tape devices.
	 */
	fas_internal_reset(fas, FAS_RESET_SOFTC|FAS_RESET_FAS|FAS_RESET_DMA);

	/*
	 * initialize period and offset for each target
	 */
	for (i = 0; i < NTARGETS_WIDE; i++) {
		if (fas->f_target_scsi_options[i] & SCSI_OPTIONS_SYNC) {
			fas->f_offset[i] = fas_default_offset |
			    fas->f_req_ack_delay;
		} else {
			fas->f_offset[i] = 0;
		}
		if (fas->f_target_scsi_options[i] & SCSI_OPTIONS_FAST) {
			fas->f_neg_period[i] =
			    (uchar_t)MIN_SYNC_PERIOD(fas);
		} else {
			fas->f_neg_period[i] =
			    (uchar_t)CONVERT_PERIOD(DEFAULT_SYNC_PERIOD);
		}
	}
	return (0);
}

/*
 * reset bus, chip, dma, or soft state
 */
static void
fas_internal_reset(struct fas *fas, int reset_action)
{
	volatile struct fasreg *fasreg = fas->f_reg;
	volatile struct dma *dmar = fas->f_dma;

	if (reset_action & FAS_RESET_SCSIBUS)	{
		fas_reg_cmd_write(fas, CMD_RESET_SCSI);
		fas_setup_reset_delay(fas);
	}

	FAS_FLUSH_DMA_HARD(fas); /* resets and reinits the dma */

	/*
	 * NOTE: if dma is aborted while active, indefinite hangs
	 * may occur; it is preferable to stop the target first before
	 * flushing the dma
	 */
	if (reset_action & FAS_RESET_DMA) {
		int burstsizes = fas->f_dma_attr->dma_attr_burstsizes;
		if (burstsizes & BURST64) {
			IPRINTF("64 byte burstsize\n");
			fas->f_dma_csr |= DMA_BURST64;
		} else if	(burstsizes & BURST32) {
			IPRINTF("32 byte burstsize\n");
			fas->f_dma_csr |= DMA_BURST32;
		} else {
			IPRINTF("16 byte burstsize\n");
		}
		if ((fas->f_hm_rev > 0x20) && (fas_enable_sbus64) &&
		    (ddi_dma_set_sbus64(fas->f_dmahandle, burstsizes) ==
		    DDI_SUCCESS)) {
			IPRINTF("enabled 64 bit sbus\n");
			fas->f_dma_csr |= DMA_WIDE_EN;
		}
	}

	if (reset_action & FAS_RESET_FAS) {
		/*
		 * 2 NOPs with DMA are required here
		 * id_code is unreliable if we don't do this)
		 */
		uchar_t idcode, fcode;
		int dmarev;

		fas_reg_cmd_write(fas, CMD_RESET_FAS);
		fas_reg_cmd_write(fas, CMD_NOP | CMD_DMA);
		fas_reg_cmd_write(fas, CMD_NOP | CMD_DMA);

		/*
		 * Re-load chip configurations
		 * Only load registers which are not loaded in fas_startcmd()
		 */
		fas_reg_write(fas, &fasreg->fas_clock_conv,
		    (fas->f_clock_conv & CLOCK_MASK));

		fas_reg_write(fas, &fasreg->fas_timeout, fas->f_stval);

		/*
		 * enable default configurations
		 */
		fas->f_idcode = idcode =
		    fas_reg_read(fas, &fasreg->fas_id_code);
		fcode = (uchar_t)(idcode & FAS_FCODE_MASK) >> (uchar_t)3;
		fas->f_type = FAS366;
		IPRINTF2("Family code %d, revision %d\n",
		    fcode, (idcode & FAS_REV_MASK));
		dmarev = fas_dma_reg_read(fas, &dmar->dma_csr);
		dmarev = (dmarev >> 11) & 0xf;
		IPRINTF1("DMA channel revision %d\n", dmarev);

		fas_reg_write(fas, &fasreg->fas_conf, fas->f_fasconf);
		fas_reg_write(fas, &fasreg->fas_conf2, fas->f_fasconf2);

		fas->f_req_ack_delay = DEFAULT_REQ_ACK_DELAY;

		/*
		 * Just in case... clear interrupt
		 */
		(void) fas_reg_read(fas, &fasreg->fas_intr);
	}

	if (reset_action & FAS_RESET_SOFTC) {
		fas->f_wdtr_sent = fas->f_sdtr_sent = 0;
		fas->f_wide_known = fas->f_sync_known = 0;
		fas->f_wide_enabled = fas->f_sync_enabled = 0;
		fas->f_omsglen = 0;
		fas->f_cur_msgout[0] = fas->f_last_msgout =
		    fas->f_last_msgin = INVALID_MSG;
		fas->f_abort_msg_sent = fas->f_reset_msg_sent = 0;
		fas->f_next_slot = 0;
		fas->f_current_sp = NULL;
		fas->f_fifolen = 0;
		fas->f_fasconf3_reg_last = fas->f_offset_reg_last =
		    fas->f_period_reg_last = 0xff;

		New_state(fas, STATE_FREE);
	}
}


#ifdef FASDEBUG
/*
 * check if ncmds still reflects the truth
 * count all cmds for this driver instance and compare with ncmds
 */
static void
fas_check_ncmds(struct fas *fas)
{
	int slot = 0;
	ushort_t tag, t;
	int n, total = 0;

	do {
		if (fas->f_active[slot]) {
			struct fas_cmd *sp = fas->f_readyf[slot];
			t = fas->f_active[slot]->f_n_slots;
			while (sp != 0) {
				sp = sp->cmd_forw;
				total++;
			}
			for (n = tag = 0; tag < t; tag++) {
				if (fas->f_active[slot]->f_slot[tag] != 0) {
					n++;
					total++;
				}
			}
			ASSERT(n == fas->f_tcmds[slot]);
		}
		slot = NEXTSLOT(slot, fas->f_dslot);
	} while (slot != 0);

	if (total != fas->f_ncmds) {
		IPRINTF2("fas_check_ncmds: total=%x, ncmds=%x\n",
		    total, fas->f_ncmds);
	}
	ASSERT(fas->f_ncmds >= fas->f_ndisc);
}
#else
#define	fas_check_ncmds(fas)
#endif

/*
 * SCSA Interface functions
 *
 * Visible to the external world via the transport structure.
 *
 * fas_scsi_abort: abort a current cmd or all cmds for a target
 */
/*ARGSUSED*/
static int
fas_scsi_abort(struct scsi_address *ap, struct scsi_pkt *pkt)
{
	struct fas *fas = ADDR2FAS(ap);
	int rval;

	IPRINTF2("fas_scsi_abort: target %d.%d\n", ap->a_target, ap->a_lun);

	mutex_enter(FAS_MUTEX(fas));
	rval =	fas_do_scsi_abort(ap, pkt);
	fas_check_waitQ_and_mutex_exit(fas);
	return (rval);
}

/*
 * reset handling: reset bus or target
 */
/*ARGSUSED*/
static int
fas_scsi_reset(struct scsi_address *ap, int level)
{
	struct fas *fas = ADDR2FAS(ap);
	int rval;

	IPRINTF3("fas_scsi_reset: target %d.%d, level %d\n",
	    ap->a_target, ap->a_lun, level);

	mutex_enter(FAS_MUTEX(fas));
	rval = fas_do_scsi_reset(ap, level);
	fas_check_waitQ_and_mutex_exit(fas);
	return (rval);
}

/*
 * entry point for reset notification setup, to register or to cancel.
 */
static int
fas_scsi_reset_notify(struct scsi_address *ap, int flag,
    void (*callback)(caddr_t), caddr_t arg)
{
	struct fas	*fas = ADDR2FAS(ap);

	return (scsi_hba_reset_notify_setup(ap, flag, callback, arg,
	    &fas->f_mutex, &fas->f_reset_notify_listf));
}

/*
 * capability interface
 */
/*ARGSUSED*/
static int
fas_scsi_getcap(struct scsi_address *ap, char *cap, int whom)
{
	struct fas *fas = ADDR2FAS(ap);
	DPRINTF3("fas_scsi_getcap: tgt=%x, cap=%s, whom=%x\n",
	    ap->a_target, cap, whom);
	return (fas_commoncap(ap, cap, 0, whom, 0));
}

/*ARGSUSED*/
static int
fas_scsi_setcap(struct scsi_address *ap, char *cap, int value, int whom)
{
	struct fas *fas = ADDR2FAS(ap);
	IPRINTF4("fas_scsi_setcap: tgt=%x, cap=%s, value=%x, whom=%x\n",
	    ap->a_target, cap, value, whom);
	return (fas_commoncap(ap, cap, value, whom, 1));
}

/*
 * pkt and dma allocation and deallocation
 */
/*ARGSUSED*/
static void
fas_scsi_dmafree(struct scsi_address *ap, struct scsi_pkt *pkt)
{
	struct fas_cmd *cmd = PKT2CMD(pkt);

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_SCSI_IMPL_DMAFREE_START,
	    "fas_scsi_dmafree_start");

	if (cmd->cmd_flags & CFLAG_DMAVALID) {
		/*
		 * Free the mapping.
		 */
		(void) ddi_dma_unbind_handle(cmd->cmd_dmahandle);
		cmd->cmd_flags ^= CFLAG_DMAVALID;
	}
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_SCSI_IMPL_DMAFREE_END,
	    "fas_scsi_dmafree_end");
}

/*ARGSUSED*/
static void
fas_scsi_sync_pkt(struct scsi_address *ap, struct scsi_pkt *pkt)
{
	struct fas_cmd *sp = PKT2CMD(pkt);

	if (sp->cmd_flags & CFLAG_DMAVALID) {
		if (ddi_dma_sync(sp->cmd_dmahandle, 0, 0,
		    (sp->cmd_flags & CFLAG_DMASEND) ?
		    DDI_DMA_SYNC_FORDEV : DDI_DMA_SYNC_FORCPU) !=
		    DDI_SUCCESS) {
			fas_log(ADDR2FAS(ap), CE_WARN,
			    "sync of pkt (%p) failed", (void *)pkt);
		}
	}
}

/*
 * initialize pkt and allocate DVMA resources
 */
static struct scsi_pkt *
fas_scsi_init_pkt(struct scsi_address *ap, struct scsi_pkt *pkt,
	struct buf *bp, int cmdlen, int statuslen, int tgtlen,
	int flags, int (*callback)(), caddr_t arg)
{
	int kf;
	int failure = 1;
	struct fas_cmd *cmd;
	struct fas *fas = ADDR2FAS(ap);
	struct fas_cmd *new_cmd;
	int rval;

/* #define	FAS_TEST_EXTRN_ALLOC */
#ifdef FAS_TEST_EXTRN_ALLOC
	cmdlen *= 4; statuslen *= 4; tgtlen *= 4;
#endif
	/*
	 * if no pkt was passed then allocate a pkt first
	 */
	if (pkt == NULL) {
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_SCSI_IMPL_PKTALLOC_START,
		    "fas_scsi_impl_pktalloc_start");

		kf = (callback == SLEEP_FUNC)? KM_SLEEP: KM_NOSLEEP;

		/*
		 * only one size of pkt (with arq).
		 */
		cmd = kmem_cache_alloc(fas->f_kmem_cache, kf);

		if (cmd) {

			ddi_dma_handle_t	save_dma_handle;

			save_dma_handle = cmd->cmd_dmahandle;
			bzero(cmd, EXTCMD_SIZE);
			cmd->cmd_dmahandle = save_dma_handle;

			pkt = (struct scsi_pkt *)((uchar_t *)cmd +
			    sizeof (struct fas_cmd));
			cmd->cmd_pkt		= pkt;
			pkt->pkt_ha_private	= (opaque_t)cmd;
			pkt->pkt_scbp	= (opaque_t)&cmd->cmd_scb;
			pkt->pkt_cdbp	= (opaque_t)&cmd->cmd_cdb;
			pkt->pkt_address	= *ap;

			pkt->pkt_cdbp = (opaque_t)&cmd->cmd_cdb;
			pkt->pkt_private = cmd->cmd_pkt_private;

			cmd->cmd_cdblen 	= cmdlen;
			cmd->cmd_scblen 	= statuslen;
			cmd->cmd_privlen	= tgtlen;
			cmd->cmd_slot		=
			    (Tgt(cmd) * NLUNS_PER_TARGET) | Lun(cmd);
			failure = 0;
		}
		if (failure || (cmdlen > sizeof (cmd->cmd_cdb)) ||
		    (tgtlen > PKT_PRIV_LEN) ||
		    (statuslen > EXTCMDS_STATUS_SIZE)) {
			if (failure == 0) {
				/*
				 * if extern alloc fails, all will be
				 * deallocated, including cmd
				 */
				failure = fas_pkt_alloc_extern(fas, cmd,
				    cmdlen, tgtlen, statuslen, kf);
			}
			if (failure) {
				/*
				 * nothing to deallocate so just return
				 */
				TRACE_0(TR_FAC_SCSI_FAS,
				    TR_FAS_SCSI_IMPL_PKTALLOC_END,
				    "fas_scsi_impl_pktalloc_end");
				return (NULL);
			}
		}

		new_cmd = cmd;

		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_SCSI_IMPL_PKTALLOC_END,
		    "fas_scsi_impl_pktalloc_end");
	} else {
		cmd = PKT2CMD(pkt);
		new_cmd = NULL;
	}

	/*
	 * Second step of fas_scsi_init_pkt:
	 * bind the buf to the handle
	 */
	if (bp && bp->b_bcount != 0 &&
	    (cmd->cmd_flags & CFLAG_DMAVALID) == 0) {

		int cmd_flags, dma_flags;
		uint_t dmacookie_count;

		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_SCSI_IMPL_DMAGET_START,
		    "fas_scsi_impl_dmaget_start");

		cmd_flags = cmd->cmd_flags;

		if (bp->b_flags & B_READ) {
			cmd_flags &= ~CFLAG_DMASEND;
			dma_flags = DDI_DMA_READ | DDI_DMA_PARTIAL;
		} else {
			cmd_flags |= CFLAG_DMASEND;
			dma_flags = DDI_DMA_WRITE | DDI_DMA_PARTIAL;
		}
		if (flags & PKT_CONSISTENT) {
			cmd_flags |= CFLAG_CMDIOPB;
			dma_flags |= DDI_DMA_CONSISTENT;
		}

		/*
		 * bind the handle to the buf
		 */
		ASSERT(cmd->cmd_dmahandle != NULL);
		rval = ddi_dma_buf_bind_handle(cmd->cmd_dmahandle, bp,
		    dma_flags, callback, arg, &cmd->cmd_dmacookie,
		    &dmacookie_count);

		if (rval && rval != DDI_DMA_PARTIAL_MAP) {
			switch (rval) {
			case DDI_DMA_NORESOURCES:
				bioerror(bp, 0);
				break;
			case DDI_DMA_BADATTR:
			case DDI_DMA_NOMAPPING:
				bioerror(bp, EFAULT);
				break;
			case DDI_DMA_TOOBIG:
			default:
				bioerror(bp, EINVAL);
				break;
			}
			cmd->cmd_flags = cmd_flags & ~CFLAG_DMAVALID;
			if (new_cmd) {
				fas_scsi_destroy_pkt(ap, pkt);
			}
			TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_SCSI_IMPL_DMAGET_END,
			    "fas_scsi_impl_dmaget_end");
			return ((struct scsi_pkt *)NULL);
		}
		ASSERT(dmacookie_count == 1);
		cmd->cmd_dmacount = bp->b_bcount;
		cmd->cmd_flags = cmd_flags | CFLAG_DMAVALID;

		ASSERT(cmd->cmd_dmahandle != NULL);
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_SCSI_IMPL_DMAGET_END,
		    "fas_scsi_impl_dmaget_end");
	}

	return (pkt);
}

/*
 * unbind dma resources and deallocate the pkt
 */
static void
fas_scsi_destroy_pkt(struct scsi_address *ap, struct scsi_pkt *pkt)
{
	struct fas_cmd *sp = PKT2CMD(pkt);
	struct fas *fas = ADDR2FAS(ap);

	/*
	 * fas_scsi_impl_dmafree inline to speed things up
	 */
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_SCSI_IMPL_DMAFREE_START,
	    "fas_scsi_impl_dmafree_start");

	if (sp->cmd_flags & CFLAG_DMAVALID) {
		/*
		 * Free the mapping.
		 */
		(void) ddi_dma_unbind_handle(sp->cmd_dmahandle);
		sp->cmd_flags ^= CFLAG_DMAVALID;
	}

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_SCSI_IMPL_DMAFREE_END,
	    "fas_scsi_impl_dmafree_end");

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_SCSI_IMPL_PKTFREE_START,
	    "fas_scsi_impl_pktfree_start");

	if ((sp->cmd_flags &
	    (CFLAG_FREE | CFLAG_CDBEXTERN | CFLAG_PRIVEXTERN |
	    CFLAG_SCBEXTERN)) == 0) {
		sp->cmd_flags = CFLAG_FREE;
		kmem_cache_free(fas->f_kmem_cache, (void *)sp);
	} else {
		fas_pkt_destroy_extern(fas, sp);
	}

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_SCSI_IMPL_PKTFREE_END,
	    "fas_scsi_impl_pktfree_end");
}

/*
 * allocate and deallocate external pkt space (ie. not part of fas_cmd) for
 * non-standard length cdb, pkt_private, status areas
 * if allocation fails, then deallocate all external space and the pkt
 */
/* ARGSUSED */
static int
fas_pkt_alloc_extern(struct fas *fas, struct fas_cmd *sp,
    int cmdlen, int tgtlen, int statuslen, int kf)
{
	caddr_t cdbp, scbp, tgt;
	int failure = 0;

	tgt = cdbp = scbp = NULL;
	if (cmdlen > sizeof (sp->cmd_cdb)) {
		if ((cdbp = kmem_zalloc((size_t)cmdlen, kf)) == NULL) {
			failure++;
		} else {
			sp->cmd_pkt->pkt_cdbp = (opaque_t)cdbp;
			sp->cmd_flags |= CFLAG_CDBEXTERN;
		}
	}
	if (tgtlen > PKT_PRIV_LEN) {
		if ((tgt = kmem_zalloc(tgtlen, kf)) == NULL) {
			failure++;
		} else {
			sp->cmd_flags |= CFLAG_PRIVEXTERN;
			sp->cmd_pkt->pkt_private = tgt;
		}
	}
	if (statuslen > EXTCMDS_STATUS_SIZE) {
		if ((scbp = kmem_zalloc((size_t)statuslen, kf)) == NULL) {
			failure++;
		} else {
			sp->cmd_flags |= CFLAG_SCBEXTERN;
			sp->cmd_pkt->pkt_scbp = (opaque_t)scbp;
		}
	}
	if (failure) {
		fas_pkt_destroy_extern(fas, sp);
	}
	return (failure);
}

/*
 * deallocate external pkt space and deallocate the pkt
 */
static void
fas_pkt_destroy_extern(struct fas *fas, struct fas_cmd *sp)
{
	if (sp->cmd_flags & CFLAG_FREE) {
		panic("fas_pkt_destroy_extern: freeing free packet");
		_NOTE(NOT_REACHED)
		/* NOTREACHED */
	}
	if (sp->cmd_flags & CFLAG_CDBEXTERN) {
		kmem_free((caddr_t)sp->cmd_pkt->pkt_cdbp,
		    (size_t)sp->cmd_cdblen);
	}
	if (sp->cmd_flags & CFLAG_SCBEXTERN) {
		kmem_free((caddr_t)sp->cmd_pkt->pkt_scbp,
		    (size_t)sp->cmd_scblen);
	}
	if (sp->cmd_flags & CFLAG_PRIVEXTERN) {
		kmem_free((caddr_t)sp->cmd_pkt->pkt_private,
		    (size_t)sp->cmd_privlen);
	}
	sp->cmd_flags = CFLAG_FREE;
	kmem_cache_free(fas->f_kmem_cache, (void *)sp);
}

/*
 * kmem cache constructor and destructor:
 * When constructing, we bzero the cmd and allocate the dma handle
 * When destructing, just free the dma handle
 */
static int
fas_kmem_cache_constructor(void	*buf, void *cdrarg, int kmflags)
{
	struct fas_cmd *cmd = buf;
	struct fas *fas = cdrarg;
	int  (*callback)(caddr_t) = (kmflags == KM_SLEEP) ? DDI_DMA_SLEEP:
	    DDI_DMA_DONTWAIT;

	bzero(buf, EXTCMD_SIZE);

	/*
	 * allocate a dma handle
	 */
	if ((ddi_dma_alloc_handle(fas->f_dev, fas->f_dma_attr, callback,
	    NULL, &cmd->cmd_dmahandle)) != DDI_SUCCESS) {
		return (-1);
	}
	return (0);
}

/*ARGSUSED*/
static void
fas_kmem_cache_destructor(void *buf, void *cdrarg)
{
	struct fas_cmd *cmd = buf;
	if (cmd->cmd_dmahandle) {
		ddi_dma_free_handle(&cmd->cmd_dmahandle);
	}
}

/*
 * fas_scsi_start - Accept commands for transport
 */
static int
fas_scsi_start(struct scsi_address *ap, struct scsi_pkt *pkt)
{
	struct fas_cmd *sp = PKT2CMD(pkt);
	struct fas *fas = ADDR2FAS(ap);
	int rval;
	int intr = 0;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_START_START, "fas_scsi_start_start");

#ifdef FAS_TEST
	if (fas_transport_busy > 0) {
		fas_transport_busy--;
		return (TRAN_BUSY);
	}
	if ((fas_transport_busy_rqs > 0) &&
	    (*(sp->cmd_pkt->pkt_cdbp) == SCMD_REQUEST_SENSE)) {
		fas_transport_busy_rqs--;
		return (TRAN_BUSY);
	}
	if (fas_transport_reject > 0) {
		fas_transport_reject--;
		return (TRAN_BADPKT);
	}
#endif
	/*
	 * prepare packet before taking the mutex
	 */
	rval = fas_prepare_pkt(fas, sp);
	if (rval != TRAN_ACCEPT) {
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_START_PREPARE_PKT_END,
		    "fas_scsi_start_end (prepare_pkt)");
		return (rval);
	}

	/*
	 * fas mutex can be held for a long time; therefore, if the mutex is
	 * held, we queue the packet in a waitQ; we now should check
	 * the waitQ on every mutex_exit(FAS_MUTEX(fas)) but we really only
	 * need to do this when the bus is free
	 * don't put NOINTR cmds including proxy cmds in waitQ! These
	 * cmds are handled by fas_runpoll()
	 * if the waitQ is non-empty, queue the pkt anyway to preserve
	 * order
	 * the goal is to queue in waitQ as much as possible so at
	 * interrupt time, we can move the packets to readyQ or start
	 * a packet immediately. It helps to do this at interrupt
	 * time because we can then field more interrupts
	 */
	if ((sp->cmd_pkt_flags & FLAG_NOINTR) == 0) {

		/*
		 * if the bus is not free, we will get an interrupt shortly
		 * so we don't want to take the fas mutex but queue up
		 * the packet in the waitQ
		 * also, if the waitQ is non-empty or there is an interrupt
		 * pending then queue up the packet in the waitQ and let the
		 * interrupt handler empty the waitQ
		 */
		mutex_enter(&fas->f_waitQ_mutex);

		if ((fas->f_state != STATE_FREE) ||
		    fas->f_waitf || (intr = INTPENDING(fas))) {
			goto queue_in_waitQ;
		}

		/*
		 * we didn't queue up in the waitQ, so now try to accept
		 * the packet. if we fail to get the fas mutex, go back to
		 * the waitQ again
		 * do not release the waitQ mutex yet because that
		 * leaves a window where the interrupt handler has
		 * emptied the waitQ but not released the fas mutex yet
		 *
		 * the interrupt handler gets the locks in opposite order
		 * but because we do a tryenter, there is no deadlock
		 *
		 * if another thread has the fas mutex then either this
		 * thread or the other may find the bus free and
		 * empty the waitQ
		 */
		if (mutex_tryenter(FAS_MUTEX(fas))) {
			mutex_exit(&fas->f_waitQ_mutex);
			rval = fas_accept_pkt(fas, sp, TRAN_BUSY_OK);
		} else {
			/*
			 * we didn't get the fas mutex so
			 * the packet has to go in the waitQ now
			 */
			goto queue_in_waitQ;
		}
	} else {
		/*
		 * for polled cmds, we have to take the mutex and
		 * start the packet using fas_runpoll()
		 */
		mutex_enter(FAS_MUTEX(fas));
		rval = fas_accept_pkt(fas, sp, TRAN_BUSY_OK);
	}

	/*
	 * if the bus is free then empty waitQ and release the mutex
	 * (this should be unlikely that the bus is still free after
	 * accepting the packet. it may be the relatively unusual case
	 * that we are throttling)
	 */
	if (fas->f_state == STATE_FREE) {
		FAS_CHECK_WAITQ_AND_FAS_MUTEX_EXIT(fas);
	} else {
		mutex_exit(FAS_MUTEX(fas));
	}

done:
	TRACE_1(TR_FAC_SCSI_FAS, TR_FAS_START_END,
	    "fas_scsi_start_end: fas 0x%p", fas);
	return (rval);

queue_in_waitQ:
	if (fas->f_waitf == NULL) {
		fas->f_waitb = fas->f_waitf = sp;
		sp->cmd_forw = NULL;
	} else {
		struct fas_cmd *dp = fas->f_waitb;
		dp->cmd_forw = fas->f_waitb = sp;
		sp->cmd_forw = NULL;
	}

	/*
	 * check again the fas mutex
	 * if there was an interrupt then the interrupt
	 * handler will eventually empty the waitQ
	 */
	if ((intr == 0) && (fas->f_state == STATE_FREE) &&
	    mutex_tryenter(FAS_MUTEX(fas))) {
		/*
		 * double check if the bus is still free
		 * (this actually reduced mutex contention a bit)
		 */
		if (fas->f_state == STATE_FREE) {
			fas_empty_waitQ(fas);
		}
		mutex_exit(FAS_MUTEX(fas));
	}
	mutex_exit(&fas->f_waitQ_mutex);

	TRACE_1(TR_FAC_SCSI_FAS, TR_FAS_START_END,
	    "fas_scsi_start_end: fas 0x%p", fas);
	return (rval);
}

/*
 * prepare the pkt:
 * the pkt may have been resubmitted or just reused so
 * initialize some fields, reset the dma window, and do some checks
 */
static int
fas_prepare_pkt(struct fas *fas, struct fas_cmd *sp)
{
	struct scsi_pkt *pkt = CMD2PKT(sp);

	/*
	 * Reinitialize some fields that need it; the packet may
	 * have been resubmitted
	 */
	pkt->pkt_reason = CMD_CMPLT;
	pkt->pkt_state	= 0;
	pkt->pkt_statistics = 0;
	pkt->pkt_resid	= 0;
	sp->cmd_age	= 0;
	sp->cmd_pkt_flags = pkt->pkt_flags;

	/*
	 * Copy the cdb pointer to the pkt wrapper area as we
	 * might modify this pointer. Zero status byte
	 */
	sp->cmd_cdbp = pkt->pkt_cdbp;
	*(pkt->pkt_scbp) = 0;

	if (sp->cmd_flags & CFLAG_DMAVALID) {
		pkt->pkt_resid	= sp->cmd_dmacount;

		/*
		 * if the pkt was resubmitted then the
		 * windows may be at the wrong number
		 */
		if (sp->cmd_cur_win) {
			sp->cmd_cur_win = 0;
			if (fas_set_new_window(fas, sp)) {
				IPRINTF("cannot reset window\n");
				return (TRAN_BADPKT);
			}
		}
		sp->cmd_saved_cur_addr =
		    sp->cmd_cur_addr = sp->cmd_dmacookie.dmac_address;

		/*
		 * the common case is just one window, we worry
		 * about multiple windows when we run out of the
		 * current window
		 */
		sp->cmd_nwin = sp->cmd_saved_win = 0;
		sp->cmd_data_count = sp->cmd_saved_data_count = 0;

		/*
		 * consistent packets need to be sync'ed first
		 * (only for data going out)
		 */
		if ((sp->cmd_flags & (CFLAG_CMDIOPB | CFLAG_DMASEND)) ==
		    (CFLAG_CMDIOPB | CFLAG_DMASEND)) {
			(void) ddi_dma_sync(sp->cmd_dmahandle,	0, (uint_t)0,
			    DDI_DMA_SYNC_FORDEV);
		}
	}

	sp->cmd_actual_cdblen = sp->cmd_cdblen;

#ifdef FAS_TEST
#ifndef __lock_lint
	if (fas_test_untagged > 0) {
		if (TAGGED(Tgt(sp))) {
			int slot = sp->cmd_slot;
			sp->cmd_pkt_flags &= ~FLAG_TAGMASK;
			sp->cmd_pkt_flags &= ~FLAG_NODISCON;
			sp->cmd_pkt_flags |= 0x80000000;
			fas_log(fas, CE_NOTE,
			    "starting untagged cmd, target=%d,"
			    " tcmds=%d, sp=0x%p, throttle=%d\n",
			    Tgt(sp), fas->f_tcmds[slot], (void *)sp,
			    fas->f_throttle[slot]);
			fas_test_untagged = -10;
		}
	}
#endif
#endif

#ifdef FASDEBUG
	if (NOTAG(Tgt(sp)) && (pkt->pkt_flags & FLAG_TAGMASK)) {
		IPRINTF2("tagged packet for non-tagged target %d.%d\n",
		    Tgt(sp), Lun(sp));
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_PREPARE_PKT_TRAN_BADPKT_END,
		    "fas_prepare_pkt_end (tran_badpkt)");
		return (TRAN_BADPKT);
	}

	/*
	 * the SCSA spec states that it is an error to have no
	 * completion function when FLAG_NOINTR is not set
	 */
	if ((pkt->pkt_comp == NULL) &&
	    ((pkt->pkt_flags & FLAG_NOINTR) == 0)) {
		IPRINTF("intr packet with pkt_comp == 0\n");
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_PREPARE_PKT_TRAN_BADPKT_END,
		    "fas_prepare_pkt_end (tran_badpkt)");
		return (TRAN_BADPKT);
	}
#endif /* FASDEBUG */

	if ((fas->f_target_scsi_options[Tgt(sp)] & SCSI_OPTIONS_DR) == 0) {
		/*
		 * no need to reset tag bits since tag queueing will
		 * not be enabled if disconnects are disabled
		 */
		sp->cmd_pkt_flags |= FLAG_NODISCON;
	}

	sp->cmd_flags = (sp->cmd_flags & ~CFLAG_TRANFLAG) |
	    CFLAG_PREPARED | CFLAG_IN_TRANSPORT;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_PREPARE_PKT_TRAN_ACCEPT_END,
	    "fas_prepare_pkt_end (tran_accept)");
	return (TRAN_ACCEPT);
}

/*
 * emptying the waitQ just before releasing FAS_MUTEX is a bit
 * tricky; if we release the waitQ mutex and then the FAS_MUTEX,
 * another thread could queue a cmd in the waitQ, just before
 * the FAS_MUTEX is released. This cmd is then stuck in the waitQ unless
 * another cmd comes in or fas_intr() or fas_watch() checks the waitQ.
 * Therefore, by releasing the FAS_MUTEX before releasing the waitQ mutex,
 * we prevent fas_scsi_start() filling the waitQ
 *
 * By setting NO_TRAN_BUSY, we force fas_accept_pkt() to queue up
 * the waitQ pkts in the readyQ.
 * If a QFull condition occurs, the target driver may set its throttle
 * too high because of the requests queued up in the readyQ but this
 * is not a big problem. The throttle should be periodically reset anyway.
 */
static void
fas_empty_waitQ(struct fas *fas)
{
	struct fas_cmd *sp;
	int rval;
	struct fas_cmd *waitf, *waitb;

	ASSERT(mutex_owned(&fas->f_waitQ_mutex));
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_EMPTY_WAITQ_START,
	    "fas_empty_waitQ_start");

	while (fas->f_waitf) {

		/* copy waitQ, zero the waitQ and release the mutex */
		waitf = fas->f_waitf;
		waitb = fas->f_waitb;
		fas->f_waitf = fas->f_waitb = NULL;
		mutex_exit(&fas->f_waitQ_mutex);

		do {
			sp = waitf;
			waitf = sp->cmd_forw;
			if (waitb == sp)	{
				waitb = NULL;
			}

			rval = fas_accept_pkt(fas, sp, NO_TRAN_BUSY);

			/*
			 * If the  packet was rejected for other reasons then
			 * complete it here
			 */
			if (rval != TRAN_ACCEPT) {
				ASSERT(rval != TRAN_BUSY);
				fas_set_pkt_reason(fas, sp, CMD_TRAN_ERR, 0);
				if (sp->cmd_pkt->pkt_comp) {
					sp->cmd_flags |= CFLAG_FINISHED;
					fas_call_pkt_comp(fas, sp);
				}
			}

			if (INTPENDING(fas)) {
				/*
				 * stop processing the waitQ and put back
				 * the remaining packets on the waitQ
				 */
				mutex_enter(&fas->f_waitQ_mutex);
				if (waitf) {
					ASSERT(waitb != NULL);
					waitb->cmd_forw = fas->f_waitf;
					fas->f_waitf = waitf;
					if (fas->f_waitb == NULL) {
						fas->f_waitb = waitb;
					}
				}
				return;
			}
		} while (waitf);

		mutex_enter(&fas->f_waitQ_mutex);
	}
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_EMPTY_WAITQ_END,
	    "fas_empty_waitQ_end");
}

static void
fas_move_waitQ_to_readyQ(struct fas *fas)
{
	/*
	 * this may actually start cmds but it is most likely
	 * that if waitQ is not empty that the bus is not free
	 */
	ASSERT(mutex_owned(FAS_MUTEX(fas)));
	mutex_enter(&fas->f_waitQ_mutex);
	fas_empty_waitQ(fas);
	mutex_exit(&fas->f_waitQ_mutex);
}


/*
 * function wrapper for two frequently used macros. for the non-critical
 * path we use the function
 */
static void
fas_check_waitQ_and_mutex_exit(struct fas *fas)
{
	_NOTE(LOCK_RELEASED_AS_SIDE_EFFECT(fas->f_mutex))
	FAS_CHECK_WAITQ_AND_FAS_MUTEX_EXIT(fas);
	FAS_EMPTY_CALLBACKQ(fas);
}

/*
 * fas_accept_pkt():
 * the flag argument is to force fas_accept_pkt to accept the pkt;
 * the caller cannot take the pkt back and it has to be queued up in
 * the readyQ
 */
static int
fas_accept_pkt(struct fas *fas, struct fas_cmd *sp, int flag)
{
	short slot = sp->cmd_slot;
	int rval = TRAN_ACCEPT;

	TRACE_0(TR_FAC_SCSI_FAS, TR__FAS_START_START, "fas_accept_pkt_start");
	ASSERT(mutex_owned(FAS_MUTEX(fas)));
	ASSERT(fas->f_ncmds >= 0 && fas->f_ndisc >= 0);
	ASSERT(fas->f_ncmds >= fas->f_ndisc);
	ASSERT(fas->f_tcmds[slot] >= 0);

	/*
	 * prepare packet for transport if this hasn't been done yet and
	 * do some checks
	 */
	if ((sp->cmd_flags & CFLAG_PREPARED) == 0) {
		rval = fas_prepare_pkt(fas, sp);
		if (rval != TRAN_ACCEPT) {
			IPRINTF1("prepare pkt failed, slot=%x\n", slot);
			sp->cmd_flags &= ~CFLAG_TRANFLAG;
			goto done;
		}
	}

	if (Lun(sp)) {
		EPRINTF("fas_accept_pkt: switching target and lun slot scan\n");
		fas->f_dslot = 1;

		if ((fas->f_active[slot] == NULL) ||
		    ((fas->f_active[slot]->f_n_slots != NTAGS) &&
		    TAGGED(Tgt(sp)))) {
			(void) fas_alloc_active_slots(fas, slot, KM_NOSLEEP);
		}
		if ((fas->f_active[slot] == NULL) ||
		    (NOTAG(Tgt(sp)) && (sp->cmd_pkt_flags & FLAG_TAGMASK))) {
			IPRINTF("fatal error on non-zero lun pkt\n");
			return (TRAN_FATAL_ERROR);
		}
	}

	/*
	 * we accepted the command; increment the count
	 * (we may still reject later if TRAN_BUSY_OK)
	 */
	fas_check_ncmds(fas);
	fas->f_ncmds++;

	/*
	 * if it is a nointr packet, start it now
	 * (NO_INTR pkts are not queued in the waitQ)
	 */
	if (sp->cmd_pkt_flags & FLAG_NOINTR) {
		EPRINTF("starting a nointr cmd\n");
		fas_runpoll(fas, slot, sp);
		sp->cmd_flags &= ~CFLAG_TRANFLAG;
		goto done;
	}

	/*
	 * reset the throttle if we were draining
	 */
	if ((fas->f_tcmds[slot] == 0) &&
	    (fas->f_throttle[slot] == DRAIN_THROTTLE)) {
		DPRINTF("reset throttle\n");
		ASSERT(fas->f_reset_delay[Tgt(sp)] == 0);
		fas_full_throttle(fas, slot);
	}

	/*
	 * accept the command:
	 * If no readyQ and no bus free, and throttle is OK,
	 * run cmd immediately.
	 */
#ifdef FASDEBUG
	fas->f_total_cmds++;
#endif

	if ((fas->f_readyf[slot] == NULL) && (fas->f_state == STATE_FREE) &&
	    (fas->f_throttle[slot] > fas->f_tcmds[slot])) {
		ASSERT(fas->f_current_sp == 0);
		(void) fas_startcmd(fas, sp);
		goto exit;
	} else {
		/*
		 * If FLAG_HEAD is set, run cmd if target and bus are
		 * available. if first cmd in ready Q is request sense
		 * then insert after this command, there shouldn't be more
		 * than one request sense.
		 */
		if (sp->cmd_pkt_flags & FLAG_HEAD) {
			struct fas_cmd *ssp = fas->f_readyf[slot];
			EPRINTF("que head\n");
			if (ssp &&
			    *(ssp->cmd_pkt->pkt_cdbp) != SCMD_REQUEST_SENSE) {
				fas_head_of_readyQ(fas, sp);
			} else if (ssp) {
				struct fas_cmd *dp = ssp->cmd_forw;
				ssp->cmd_forw = sp;
				sp->cmd_forw = dp;
				if (fas->f_readyb[slot] == ssp) {
					fas->f_readyb[slot] = sp;
				}
			} else {
				fas->f_readyf[slot] = fas->f_readyb[slot] = sp;
				sp->cmd_forw = NULL;
			}

		/*
		 * for tagged targets, check for qfull condition and
		 * return TRAN_BUSY (if permitted), if throttle has been
		 * exceeded
		 */
		} else if (TAGGED(Tgt(sp)) &&
		    (fas->f_tcmds[slot] >= fas->f_throttle[slot]) &&
		    (fas->f_throttle[slot] > HOLD_THROTTLE) &&
		    (flag == TRAN_BUSY_OK)) {
			IPRINTF2(
			    "transport busy, slot=%x, ncmds=%x\n",
			    slot, fas->f_ncmds);
			rval = TRAN_BUSY;
			fas->f_ncmds--;
			sp->cmd_flags &=
			    ~(CFLAG_PREPARED | CFLAG_IN_TRANSPORT);
			goto done;
			/*
			 * append to readyQ or start a new readyQ
			 */
		} else if (fas->f_readyf[slot]) {
			struct fas_cmd *dp = fas->f_readyb[slot];
			ASSERT(dp != 0);
			fas->f_readyb[slot] = sp;
			sp->cmd_forw = NULL;
			dp->cmd_forw = sp;
		} else {
			fas->f_readyf[slot] = fas->f_readyb[slot] = sp;
			sp->cmd_forw = NULL;
		}

	}

done:
	/*
	 * just in case that the bus is free and we haven't
	 * been able to restart for some reason
	 */
	if (fas->f_state == STATE_FREE) {
		(void) fas_istart(fas);
	}

exit:
	fas_check_ncmds(fas);
	ASSERT(mutex_owned(FAS_MUTEX(fas)));
	TRACE_0(TR_FAC_SCSI_FAS, TR__FAS_START_END,	"fas_accept_pkt_end");
	return (rval);
}

/*
 * allocate a tag byte and check for tag aging
 */
static char fas_tag_lookup[] =
	{0, MSG_HEAD_QTAG, MSG_ORDERED_QTAG, 0, MSG_SIMPLE_QTAG};

static int
fas_alloc_tag(struct fas *fas, struct fas_cmd *sp)
{
	struct f_slots *tag_slots;
	int tag;
	short slot = sp->cmd_slot;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_ALLOC_TAG_START, "fas_alloc_tag_start");
	ASSERT(mutex_owned(FAS_MUTEX(fas)));

	tag_slots = fas->f_active[slot];
	ASSERT(tag_slots->f_n_slots == NTAGS);

alloc_tag:
	tag = (fas->f_active[slot]->f_tags)++;
	if (fas->f_active[slot]->f_tags >= NTAGS) {
		/*
		 * we reserve tag 0 for non-tagged cmds
		 */
		fas->f_active[slot]->f_tags = 1;
	}
	EPRINTF1("tagged cmd, tag = %d\n", tag);

	/* Validate tag, should never fail. */
	if (tag_slots->f_slot[tag] == 0) {
		/*
		 * Store assigned tag and tag queue type.
		 * Note, in case of multiple choice, default to simple queue.
		 */
		ASSERT(tag < NTAGS);
		sp->cmd_tag[1] = (uchar_t)tag;
		sp->cmd_tag[0] = fas_tag_lookup[((sp->cmd_pkt_flags &
		    FLAG_TAGMASK) >> 12)];
		EPRINTF1("tag= %d\n", tag);
		tag_slots->f_slot[tag] = sp;
		(fas->f_tcmds[slot])++;
		ASSERT(mutex_owned(FAS_MUTEX(fas)));
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_ALLOC_TAG_END,
		    "fas_alloc_tag_end");
		return (0);

	} else {
		int age, i;

		/*
		 * Check tag age.  If timeouts enabled and
		 * tag age greater than 1, print warning msg.
		 * If timeouts enabled and tag age greater than
		 * age limit, begin draining tag que to check for
		 * lost tag cmd.
		 */
		age = tag_slots->f_slot[tag]->cmd_age++;
		if (age >= fas->f_scsi_tag_age_limit &&
		    tag_slots->f_slot[tag]->cmd_pkt->pkt_time) {
			IPRINTF2("tag %d in use, age= %d\n", tag, age);
			DPRINTF("draining tag queue\n");
			if (fas->f_reset_delay[Tgt(sp)] == 0) {
				fas->f_throttle[slot] = DRAIN_THROTTLE;
			}
		}

		/* If tag in use, scan until a free one is found. */
		for (i = 1; i < NTAGS; i++) {
			tag = fas->f_active[slot]->f_tags;
			if (!tag_slots->f_slot[tag]) {
				EPRINTF1("found free tag %d\n", tag);
				break;
			}
			if (++(fas->f_active[slot]->f_tags) >= NTAGS) {
			/*
			 * we reserve tag 0 for non-tagged cmds
			 */
				fas->f_active[slot]->f_tags = 1;
			}
			EPRINTF1("found in use tag %d\n", tag);
		}

		/*
		 * If no free tags, we're in serious trouble.
		 * the target driver submitted more than 255
		 * requests
		 */
		if (tag_slots->f_slot[tag]) {
			IPRINTF1("slot %x: All tags in use!!!\n", slot);
			goto fail;
		}
		goto alloc_tag;
	}

fail:
	fas_head_of_readyQ(fas, sp);

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_ALLOC_TAG_END,
	    "fas_alloc_tag_end");
	return (-1);
}

/*
 * Internal Search Routine.
 *
 * Search for a command to start.
 */
static int
fas_istart(struct fas *fas)
{
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_ISTART_START,
	    "fas_istart_start");
	EPRINTF("fas_istart:\n");

	if (fas->f_state == STATE_FREE && fas->f_ncmds > fas->f_ndisc) {
		(void) fas_ustart(fas);
	}
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_ISTART_END,
	    "fas_istart_end");
	return (ACTION_RETURN);
}

static int
fas_ustart(struct fas *fas)
{
	struct fas_cmd *sp;
	short slot = fas->f_next_slot;
	short start_slot = slot;
	short dslot = fas->f_dslot;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_USTART_START, "fas_ustart_start");
	EPRINTF1("fas_ustart: start_slot=%x\n", fas->f_next_slot);
	ASSERT(fas->f_current_sp == NULL);
	ASSERT(dslot != 0);
	if (dslot == NLUNS_PER_TARGET) {
		ASSERT((slot % NLUNS_PER_TARGET) == 0);
	}

	/*
	 * if readyQ not empty and we are not draining, then we
	 * can start another cmd
	 */
	do {
		/*
		 * If all cmds drained from tag Q, back to full throttle and
		 * start queueing up new cmds again.
		 */
		if (fas->f_throttle[slot] == DRAIN_THROTTLE &&
		    fas->f_tcmds[slot] == 0) {
			fas_full_throttle(fas, slot);
		}

		if (fas->f_readyf[slot] &&
		    (fas->f_throttle[slot] > fas->f_tcmds[slot])) {
			sp = fas->f_readyf[slot];
			fas->f_readyf[slot] = sp->cmd_forw;
			if (sp->cmd_forw == NULL) {
				fas->f_readyb[slot] = NULL;
			}
			fas->f_next_slot = NEXTSLOT(slot, dslot);
			ASSERT((sp->cmd_pkt_flags & FLAG_NOINTR) == 0);
			TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_USTART_END,
			    "fas_ustart_end");
			return (fas_startcmd(fas, sp));
		} else {
			slot = NEXTSLOT(slot, dslot);
		}
	} while (slot != start_slot);

	EPRINTF("fas_ustart: no cmds to start\n");
	fas->f_next_slot = NEXTSLOT(slot, dslot);
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_USTART_NOT_FOUND_END,
	    "fas_ustart_end (not_found)");
	return (FALSE);
}

/*
 * Start a command off
 */
static int
fas_startcmd(struct fas *fas, struct fas_cmd *sp)
{
	volatile struct fasreg *fasreg = fas->f_reg;
	ushort_t  nstate;
	uchar_t cmd, target, lun;
	ushort_t tshift;
	volatile uchar_t *tp = fas->f_cmdarea;
	struct scsi_pkt *pkt = CMD2PKT(sp);
	int slot = sp->cmd_slot;
	struct f_slots *slots = fas->f_active[slot];
	int i, cdb_len;

#define	LOAD_CMDP	*(tp++)

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_STARTCMD_START, "fas_startcmd_start");

	EPRINTF2("fas_startcmd: sp=0x%p flags=%x\n",
	    (void *)sp, sp->cmd_pkt_flags);
	ASSERT((sp->cmd_flags & CFLAG_FREE) == 0);
	ASSERT((sp->cmd_flags & CFLAG_COMPLETED) == 0);
	ASSERT(fas->f_current_sp == NULL && fas->f_state == STATE_FREE);
	if ((sp->cmd_pkt_flags & FLAG_NOINTR) == 0) {
		ASSERT(fas->f_throttle[slot] > 0);
		ASSERT(fas->f_reset_delay[Tgt(sp)] == 0);
	}

	target		= Tgt(sp);
	lun		= Lun(sp);

	/*
	 * if a non-tagged cmd is submitted to an active tagged target
	 * then drain before submitting this cmd; SCSI-2 allows RQSENSE
	 * to be untagged
	 */
	if (((sp->cmd_pkt_flags & FLAG_TAGMASK) == 0) &&
	    TAGGED(target) && fas->f_tcmds[slot] &&
	    ((sp->cmd_flags & CFLAG_CMDPROXY) == 0) &&
	    (*(sp->cmd_pkt->pkt_cdbp) != SCMD_REQUEST_SENSE)) {
		if ((sp->cmd_pkt_flags & FLAG_NOINTR) == 0) {
			struct fas_cmd *dp;

			IPRINTF("untagged cmd, start draining\n");

			if (fas->f_reset_delay[Tgt(sp)] == 0) {
				fas->f_throttle[slot] = DRAIN_THROTTLE;
			}
			dp = fas->f_readyf[slot];
			fas->f_readyf[slot] = sp;
			sp->cmd_forw = dp;
			if (fas->f_readyb[slot] == NULL) {
				fas->f_readyb[slot] = sp;
			}
		}
		return (FALSE);
	}

	/*
	 * allocate a tag; if no tag available then put request back
	 * on the ready queue and return; eventually a cmd returns and we
	 * get going again or we timeout
	 */
	if (TAGGED(target) && (sp->cmd_pkt_flags & FLAG_TAGMASK)) {
		if (fas_alloc_tag(fas, sp)) {
			return (FALSE);
		}
	} else {
		/*
		 * tag slot 0 is reserved for non-tagged cmds
		 * and should be empty because we have drained
		 */
		if ((sp->cmd_flags & CFLAG_CMDPROXY) == 0) {
			ASSERT(fas->f_active[slot]->f_slot[0] == NULL);
			fas->f_active[slot]->f_slot[0] = sp;
			sp->cmd_tag[1] = 0;
			if (*(sp->cmd_pkt->pkt_cdbp) != SCMD_REQUEST_SENSE) {
				ASSERT(fas->f_tcmds[slot] == 0);
				/*
				 * don't start any other cmd until this
				 * one is finished. The throttle is reset
				 * later in fas_watch()
				 */
				fas->f_throttle[slot] = 1;
			}
			(fas->f_tcmds[slot])++;

		}
	}

	fas->f_current_sp = sp;
	fas->f_omsglen	= 0;
	tshift		= 1<<target;
	fas->f_sdtr_sent = fas->f_wdtr_sent =	0;
	cdb_len 	= sp->cmd_actual_cdblen;

	if (sp->cmd_pkt_flags & FLAG_RENEGOTIATE_WIDE_SYNC) {
		fas_force_renegotiation(fas, Tgt(sp));
	}

	/*
	 * first send identify message, with or without disconnect priv.
	 */
	if (sp->cmd_pkt_flags & FLAG_NODISCON) {
		LOAD_CMDP = fas->f_last_msgout = MSG_IDENTIFY | lun;
		ASSERT((sp->cmd_pkt_flags & FLAG_TAGMASK) == 0);
	} else {
		LOAD_CMDP = fas->f_last_msgout = MSG_DR_IDENTIFY | lun;
	}

	/*
	 * normal case, tagQ and we have negotiated wide and sync
	 * or we don't need to renegotiate because wide and sync
	 * have been disabled
	 * (proxy msg's don't have tag flag set)
	 */
	if ((sp->cmd_pkt_flags & FLAG_TAGMASK) &&
	    ((fas->f_wide_known | fas->f_nowide) &
	    (fas->f_sync_known | fas->f_nosync) & tshift)) {

		EPRINTF("tag cmd\n");
		ASSERT((sp->cmd_pkt_flags & FLAG_NODISCON) == 0);

		fas->f_last_msgout = LOAD_CMDP = sp->cmd_tag[0];
		LOAD_CMDP = sp->cmd_tag[1];

		nstate = STATE_SELECT_NORMAL;
		cmd = CMD_SEL_ATN3 | CMD_DMA;

	/*
	 * is this a proxy message
	 */
	} else if (sp->cmd_flags & CFLAG_CMDPROXY) {

		IPRINTF2("proxy cmd, len=%x, msg=%x\n",
		    sp->cmd_cdb[FAS_PROXY_DATA],
		    sp->cmd_cdb[FAS_PROXY_DATA+1]);
		/*
		 * This is a proxy command. It will have
		 * a message to send as part of post-selection
		 * (e.g, MSG_ABORT or MSG_DEVICE_RESET)
		 */
		fas->f_omsglen = sp->cmd_cdb[FAS_PROXY_DATA];
		for (i = 0; i < (uint_t)fas->f_omsglen; i++) {
			fas->f_cur_msgout[i] =
			    sp->cmd_cdb[FAS_PROXY_DATA+1+i];
		}
		sp->cmd_cdb[FAS_PROXY_RESULT] = FALSE;
		cdb_len = 0;
		cmd = CMD_SEL_STOP | CMD_DMA;
		nstate = STATE_SELECT_N_SENDMSG;

	/*
	 * always negotiate wide first and sync after wide
	 */
	} else if (((fas->f_wide_known | fas->f_nowide) & tshift) == 0) {
		int i = 0;

		/* First the tag message bytes */
		if (sp->cmd_pkt_flags & FLAG_TAGMASK) {
			fas->f_cur_msgout[i++] = sp->cmd_tag[0];
			fas->f_cur_msgout[i++] = sp->cmd_tag[1];
		}

		/*
		 * Set up to send wide negotiating message.  This is getting
		 * a bit tricky as we dma out the identify message and
		 * send the other messages via the fifo buffer.
		 */
		EPRINTF1("cmd with wdtr msg, tag=%x\n", sp->cmd_tag[1]);

		fas_make_wdtr(fas, i, target, FAS_XFER_WIDTH);

		cdb_len = 0;
		nstate = STATE_SELECT_N_SENDMSG;
		cmd = CMD_SEL_STOP | CMD_DMA;

	/*
	 * negotiate sync xfer rate
	 */
	} else if (((fas->f_sync_known | fas->f_nosync) & tshift) == 0) {
		int i = 0;
		/*
		 * Set up to send sync negotiating message.  This is getting
		 * a bit tricky as we dma out the identify message and
		 * send the other messages via the fifo buffer.
		 */
		if (sp->cmd_pkt_flags & FLAG_TAGMASK) {
			fas->f_cur_msgout[i++] = sp->cmd_tag[0];
			fas->f_cur_msgout[i++] = sp->cmd_tag[1];
		}

		fas_make_sdtr(fas, i, target);

		cdb_len = 0;
		cmd = CMD_SEL_STOP | CMD_DMA;
		nstate = STATE_SELECT_N_SENDMSG;

	/*
	 * normal cmds, no negotiations and not a proxy and no TQ
	 */
	} else {

		ASSERT((sp->cmd_pkt_flags & FLAG_TAGMASK) == 0);
		EPRINTF("std. cmd\n");

		nstate = STATE_SELECT_NORMAL;
		cmd = CMD_SEL_ATN | CMD_DMA;
	}

	/*
	 * Now load cdb (if any)
	 */
	for (i = 0; i < cdb_len; i++) {
		LOAD_CMDP = sp->cmd_cdbp[i];
	}

	/*
	 * calculate total dma amount:
	 */
	fas->f_lastcount = (uintptr_t)tp - (uintptr_t)fas->f_cmdarea;

	/*
	 * load target id and enable bus id encoding and 32 bit counter
	 */
	fas_reg_write(fas, (uchar_t *)&fasreg->fas_busid,
	    (target & 0xf) | FAS_BUSID_ENCODID | FAS_BUSID_32BIT_COUNTER);

	FAS_SET_PERIOD_OFFSET_CONF3_REGS(fas, target);

	fas_reg_cmd_write(fas, CMD_FLUSH);

	FAS_DMA_READ(fas, fas->f_lastcount,
	    fas->f_dmacookie.dmac_address, 16, cmd);

	New_state(fas, (int)nstate);

#ifdef FASDEBUG
	if (DDEBUGGING) {
		fas_dump_cmd(fas, sp);
	}
#endif /* FASDEBUG */

	/*
	 * if timeout == 0, then it has no effect on the timeout
	 * handling; we deal with this when an actual timeout occurs.
	 */
	if ((sp->cmd_flags & CFLAG_CMDPROXY) == 0) {
		ASSERT(fas->f_tcmds[slot] >= 1);
	}
	i = pkt->pkt_time - slots->f_timebase;

	if (i == 0) {
		EPRINTF("dup timeout\n");
		(slots->f_dups)++;
		slots->f_timeout = slots->f_timebase;
	} else if (i > 0) {
		EPRINTF("new timeout\n");
		slots->f_timeout = slots->f_timebase = pkt->pkt_time;
		slots->f_dups = 1;
	}

	fas_check_ncmds(fas);

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_STARTCMD_END, "fas_startcmd_end");

	return (TRUE);
}

/*
 * Interrupt Entry Point.
 * Poll interrupts until they go away
 */
static uint_t
fas_intr(caddr_t arg)
{
	struct fas *fas = (struct fas *)arg;
	int rval = DDI_INTR_UNCLAIMED;
	int kstat_updated = 0;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_POLL_START, "fas_intr_start");

	do {
		mutex_enter(FAS_MUTEX(fas));

		do {
			if (fas_intr_svc(fas)) {
				/*
				 * do not return immediately here because
				 * we have to guarantee to always empty
				 * the waitQ and callbackQ in the interrupt
				 * handler
				 */
				if (fas->f_polled_intr) {
					rval = DDI_INTR_CLAIMED;
					fas->f_polled_intr = 0;
				}
			} else {
				rval = DDI_INTR_CLAIMED;
			}
		} while (INTPENDING(fas));

		if (!kstat_updated && fas->f_intr_kstat &&
		    rval == DDI_INTR_CLAIMED) {
			FAS_KSTAT_INTR(fas);
			kstat_updated++;
		}

		/*
		 * check and empty the waitQ and the callbackQ
		 */
		FAS_CHECK_WAITQ_AND_FAS_MUTEX_EXIT(fas);
		FAS_EMPTY_CALLBACKQ(fas);

	} while (INTPENDING(fas));

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_POLL_END, "fas_intr_end");

	return (rval);
}

/*
 * General interrupt service routine.
 */
static char *dma_bits	= DMA_BITS;

static int
fas_intr_svc(struct fas *fas)
{
	static int (*evec[])(struct fas *fas) = {
		fas_finish_select,
		fas_reconnect,
		fas_phasemanage,
		fas_finish,
		fas_reset_recovery,
		fas_istart,
		fas_abort_curcmd,
		fas_reset_bus,
		fas_reset_bus,
		fas_handle_selection
	};
	int action;
	uchar_t intr, stat;
	volatile struct fasreg *fasreg = fas->f_reg;
	int i = 0;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FASSVC_START, "fas_intr_svc_start");

	/*
	 * A read of FAS interrupt register clears interrupt,
	 * so any other volatile information needs to be latched
	 * up prior to reading the interrupt register.
	 */
	fas->f_stat = fas_reg_read(fas, &fasreg->fas_stat);

	EPRINTF2("fas_intr_svc: state=%x stat=%x\n", fas->f_state,
	    fas->f_stat);

	/*
	 * this wasn't our interrupt?
	 */
	if ((fas->f_stat & FAS_STAT_IPEND) == 0) {
		if (fas_check_dma_error(fas)) {
			action = ACTION_RESET;
			goto start_action;
		}
		return (-1);
	}

	/*
	 * if we are reset state, handle this first
	 */
	if (fas->f_state == ACTS_RESET) {
		action = ACTION_FINRST;
		goto start_action;
	}

	/*
	 * check for gross error.  fas366 hardware seems to register
	 * the gross error bit when a parity error is found.  Make sure
	 * to ignore the gross error bit when a parity error is detected.
	 */
	if ((fas->f_stat & FAS_STAT_GERR) &&
	    (fas->f_stat & FAS_STAT_PERR) == 0) {
		action = fas_handle_gross_err(fas);
		goto start_action;
	}

	/*
	 * now it is finally safe to read the interrupt register
	 * if we haven't done so yet
	 * Note: we don't read step register here but only in
	 * fas_finish_select(). It is not entirely safe but saves
	 * redundant PIOs or extra code in this critical path
	 */
	fas->f_intr =
	    intr = fas_reg_read(fas, (uchar_t *)&fasreg->fas_intr);

	/*
	 * read the fifo if there is something there or still in the
	 * input shuttle
	 */
	stat = fas->f_stat & FAS_PHASE_MASK;

	if ((intr & FAS_INT_RESEL) ||
	    ((stat != FAS_PHASE_DATA_IN) && (stat != FAS_PHASE_DATA_OUT) &&
	    ((fas->f_state & STATE_SELECTING) == 0) &&
	    (fas->f_state != ACTS_DATA_DONE) &&
	    (fas->f_state != ACTS_C_CMPLT))) {

		fas->f_stat2 = fas_reg_read(fas, &fasreg->fas_stat2);

		if (((fas->f_stat2 & FAS_STAT2_EMPTY) == 0) ||
		    (fas->f_stat2 & FAS_STAT2_ISHUTTLE)) {
			fas_read_fifo(fas);
		}
	}

	EPRINTF2("fas_intr_svc: intr=%x, stat=%x\n", fas->f_intr, fas->f_stat);
	EPRINTF2("dmacsr=%b\n", fas->f_dma->dma_csr, dma_bits);

	/*
	 * Based upon the current state of the host adapter driver
	 * we should be able to figure out what to do with an interrupt.
	 *
	 * The FAS asserts an interrupt with one or more of 8 possible
	 * bits set in its interrupt register. These conditions are
	 * SCSI bus reset detected, an illegal command fed to the FAS,
	 * one of DISCONNECT, BUS SERVICE, FUNCTION COMPLETE conditions
	 * for the FAS, a Reselection interrupt, or one of Selection
	 * or Selection with Attention.
	 *
	 * Of these possible interrupts, we can deal with some right
	 * here and now, irrespective of the current state of the driver.
	 *
	 * take care of the most likely interrupts first and call the action
	 * immediately
	 */
	if ((intr & (FAS_INT_RESET|FAS_INT_ILLEGAL|FAS_INT_SEL|FAS_INT_SELATN|
	    FAS_INT_RESEL)) == 0) {
		/*
		 * The rest of the reasons for an interrupt can
		 * be handled based purely on the state that the driver
		 * is currently in now.
		 */
		if (fas->f_state & STATE_SELECTING) {
			action = fas_finish_select(fas);

		} else if (fas->f_state & STATE_ITPHASES) {
			action = fas_phasemanage(fas);

		} else {
			fas_log(fas, CE_WARN, "spurious interrupt");
			action = ACTION_RETURN;
		}

	} else if ((intr & FAS_INT_RESEL) && ((intr &
	    (FAS_INT_RESET|FAS_INT_ILLEGAL|FAS_INT_SEL|FAS_INT_SELATN)) == 0)) {

		if ((fas->f_state & STATE_SELECTING) == 0) {
			ASSERT(fas->f_state == STATE_FREE);
			action = fas_reconnect(fas);
		} else {
			action = fas_reselect_preempt(fas);
		}

	} else if (intr & (FAS_INT_RESET | FAS_INT_ILLEGAL)) {
		action = fas_illegal_cmd_or_bus_reset(fas);

	} else if (intr & (FAS_INT_SEL|FAS_INT_SELATN)) {
		action = ACTION_SELECT;
	}

start_action:
	while (action != ACTION_RETURN) {
		ASSERT((action >= 0) && (action <= ACTION_SELECT));
		TRACE_3(TR_FAC_SCSI_FAS, TR_FASSVC_ACTION_CALL,
		    "fas_intr_svc call: fas 0x%p, action %d (%d)",
		    fas, action, i);
		i++;
		action = (*evec[action])(fas);
	}
exit:
	TRACE_0(TR_FAC_SCSI_FAS, TR_FASSVC_END, "fas_intr_svc_end");

	return (0);
}

/*
 * Manage phase transitions.
 */
static int
fas_phasemanage(struct fas *fas)
{
	ushort_t state;
	int action;
	static int (*pvecs[])(struct fas *fas) = {
		fas_handle_cmd_start,
		fas_handle_cmd_done,
		fas_handle_msg_out_start,
		fas_handle_msg_out_done,
		fas_handle_msg_in_start,
		fas_handle_more_msgin,
		fas_handle_msg_in_done,
		fas_handle_clearing,
		fas_handle_data_start,
		fas_handle_data_done,
		fas_handle_c_cmplt,
		fas_reconnect,
		fas_handle_unknown,
		fas_reset_recovery
	};
	int i = 0;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_PHASEMANAGE_START,
	    "fas_phasemanage_start");

	do {
		EPRINTF1("fas_phasemanage: %s\n",
		    fas_state_name(fas->f_state & STATE_ITPHASES));

		TRACE_2(TR_FAC_SCSI_FAS, TR_FAS_PHASEMANAGE_CALL,
		    "fas_phasemanage_call: fas 0x%p (%d)", fas, i++);

		state = fas->f_state;

		if (!(state == STATE_FREE || state > ACTS_ENDVEC)) {
			ASSERT(pvecs[state-1] != NULL);
			action = (*pvecs[state-1]) (fas);
		} else {
			fas_log(fas, CE_WARN, "lost state in phasemanage");
			action = ACTION_ABORT_ALLCMDS;
		}

	} while (action == ACTION_PHASEMANAGE);

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_PHASEMANAGE_END,
	    "fas_phasemanage_end");
	return (action);
}

/*
 * remove a cmd from active list and if timeout flag is set, then
 * adjust timeouts; if a the same cmd will be resubmitted soon, don't
 * bother to adjust timeouts (ie. don't set this flag)
 */
static void
fas_remove_cmd(struct fas *fas, struct fas_cmd *sp, int new_timeout_flag)
{
	int tag = sp->cmd_tag[1];
	int slot = sp->cmd_slot;
	struct f_slots *tag_slots = fas->f_active[slot];

	ASSERT(sp != NULL);
	EPRINTF4("remove tag %d slot %d for target %d.%d\n",
	    tag, slot, Tgt(sp), Lun(sp));

	if (sp == tag_slots->f_slot[tag]) {
		tag_slots->f_slot[tag] = NULL;
		fas->f_tcmds[slot]--;
	}
	if (fas->f_current_sp == sp) {
		fas->f_current_sp = NULL;
	}

	ASSERT(sp != fas->f_active[sp->cmd_slot]->f_slot[sp->cmd_tag[1]]);

	if (new_timeout_flag != NEW_TIMEOUT) {
		return;
	}

	/*
	 * Figure out what to set tag Q timeout for...
	 *
	 * Optimize: If we have duplicate's of same timeout
	 * we're using, then we'll use it again until we run
	 * out of duplicates.  This should be the normal case
	 * for block and raw I/O.
	 * If no duplicates, we have to scan through tag que and
	 * find the longest timeout value and use it.  This is
	 * going to take a while...
	 */
	if (sp->cmd_pkt->pkt_time == tag_slots->f_timebase) {
		if (--(tag_slots->f_dups) <= 0) {
			if (fas->f_tcmds[slot]) {
				struct fas_cmd *ssp;
				uint_t n = 0;
				ushort_t t = tag_slots->f_n_slots;
				ushort_t i;
				/*
				 * This crude check assumes we don't do
				 * this too often which seems reasonable
				 * for block and raw I/O.
				 */
				for (i = 0; i < t; i++) {
					ssp = tag_slots->f_slot[i];
					if (ssp &&
					    (ssp->cmd_pkt->pkt_time > n)) {
						n = ssp->cmd_pkt->pkt_time;
						tag_slots->f_dups = 1;
					} else if (ssp &&
					    (ssp->cmd_pkt->pkt_time == n)) {
						tag_slots->f_dups++;
					}
				}
				tag_slots->f_timebase = n;
				EPRINTF1("searching, new_timeout= %d\n", n);
			} else {
				tag_slots->f_dups = 0;
				tag_slots->f_timebase = 0;
			}
		}
	}
	tag_slots->f_timeout = tag_slots->f_timebase;

	ASSERT(fas->f_ncmds >= fas->f_ndisc);
}

/*
 * decrement f_ncmds and f_ndisc for this cmd before completing
 */
static void
fas_decrement_ncmds(struct fas *fas, struct fas_cmd *sp)
{
	ASSERT((sp->cmd_flags & CFLAG_FREE) == 0);
	if ((sp->cmd_flags & CFLAG_FINISHED) == 0) {
		fas->f_ncmds--;
		if (sp->cmd_flags & CFLAG_CMDDISC) {
			fas->f_ndisc--;
		}
		sp->cmd_flags |= CFLAG_FINISHED;
		sp->cmd_flags &= ~CFLAG_CMDDISC;
	}
	ASSERT((fas->f_ncmds >= 0) && (fas->f_ndisc >= 0));
	ASSERT(fas->f_ncmds >= fas->f_ndisc);
}

/*
 * Most commonly called phase handlers:
 *
 * Finish routines
 */
static int
fas_finish(struct fas *fas)
{
	struct fas_cmd *sp = fas->f_current_sp;
	struct scsi_pkt *pkt = CMD2PKT(sp);
	int action = ACTION_SEARCH;
	struct scsi_status *status =
	    (struct  scsi_status *)sp->cmd_pkt->pkt_scbp;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_FINISH_START,
	    "fas_finish_start");
	EPRINTF("fas_finish\n");

#ifdef FAS_TEST
	if (fas_test_stop && (sp->cmd_pkt_flags & 0x80000000)) {
		debug_enter("untagged cmd completed");
	}
#endif

	/*
	 * immediately enable reselects
	 */
	fas_reg_cmd_write(fas, CMD_EN_RESEL);
	if (status->sts_chk) {
		/*
		 * In the case that we are getting a check condition
		 * clear our knowledge of synchronous capabilities.
		 * This will unambiguously force a renegotiation
		 * prior to any possible data transfer (we hope),
		 * including the data transfer for a UNIT ATTENTION
		 * condition generated by somebody powering on and
		 * off a target.
		 */
		fas_force_renegotiation(fas, Tgt(sp));
	}

	/*
	 * backoff sync/wide if there were parity errors
	 */
	if (sp->cmd_pkt->pkt_statistics & STAT_PERR) {
		fas_sync_wide_backoff(fas, sp, sp->cmd_slot);
#ifdef FAS_TEST
		if (fas_test_stop) {
			debug_enter("parity error");
		}
#endif
	}

	/*
	 * Free from active list and update counts
	 * We need to clean up this cmd now, just in case fas_ustart()
	 * hits a reset or other fatal transport error
	 */
	fas_check_ncmds(fas);
	fas_remove_cmd(fas, sp, NEW_TIMEOUT);
	fas_decrement_ncmds(fas, sp);
	fas_check_ncmds(fas);

	/*
	 * go to state free and try to start a new cmd now
	 */
	New_state(fas, STATE_FREE);

	if ((fas->f_ncmds > fas->f_ndisc) && (*((char *)status) == 0) &&
	    (INTPENDING(fas) == 0)) {
		if (fas_ustart(fas)) {
			action = ACTION_RETURN;
		}
	}

	/*
	 * if there was a data xfer then calculate residue and
	 * sync data for consistent memory xfers
	 */
	if (pkt->pkt_state & STATE_XFERRED_DATA) {
		pkt->pkt_resid = sp->cmd_dmacount - sp->cmd_data_count;
		if (sp->cmd_flags & CFLAG_CMDIOPB) {
			(void) ddi_dma_sync(sp->cmd_dmahandle, 0, (uint_t)0,
			    DDI_DMA_SYNC_FORCPU);
		}
		if (pkt->pkt_resid) {
			IPRINTF3("%d.%d finishes with %ld resid\n",
			    Tgt(sp), Lun(sp), pkt->pkt_resid);
		}
	}

	if (sp->cmd_pkt_flags & FLAG_NOINTR) {
		fas_call_pkt_comp(fas, sp);
		action = ACTION_RETURN;
	} else {
		/*
		 * start an autorequest sense if there was a check condition.
		 * if arq has not been enabled, fas_handle_sts_chk will do
		 * do the callback
		 */
		if (status->sts_chk) {
			if (fas_handle_sts_chk(fas, sp)) {
				/*
				 * we can't start an arq because one is
				 * already in progress. the target is
				 * probably confused
				 */
				action = ACTION_ABORT_CURCMD;
			}
		} else if ((*((char *)status) & STATUS_MASK) ==
		    STATUS_QFULL) {
			fas_handle_qfull(fas, sp);
		} else {
#ifdef FAS_TEST
			if (fas_arqs_failure && (status->sts_chk == 0)) {
				struct scsi_arq_status *arqstat;
				status->sts_chk = 1;
				arqstat = (struct scsi_arq_status *)
				    (sp->cmd_pkt->pkt_scbp);
				arqstat->sts_rqpkt_reason = CMD_TRAN_ERR;
				sp->cmd_pkt->pkt_state |= STATE_ARQ_DONE;
				fas_arqs_failure = 0;
			}
			if (fas_tran_err) {
				sp->cmd_pkt->pkt_reason = CMD_TRAN_ERR;
				fas_tran_err = 0;
			}
#endif
			fas_call_pkt_comp(fas, sp);
		}
	}

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_FINISH_END, "fas_finish_end");
	return (action);
}

/*
 * Complete the process of selecting a target
 */
static int
fas_finish_select(struct fas *fas)
{
	volatile struct dma *dmar = fas->f_dma;
	struct fas_cmd *sp = fas->f_current_sp;
	uchar_t intr = fas->f_intr;
	uchar_t step;

	step = fas_reg_read(fas, &fas->f_reg->fas_step) & FAS_STEP_MASK;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_FINISH_SELECT_START,
	    "fas_finish_select_start");
	EPRINTF("fas_finish_select:\n");
	ASSERT(sp != 0);

	/*
	 * Check for DMA gate array errors
	 */
	if ((fas->f_dma_csr = fas_dma_reg_read(fas, &dmar->dma_csr))
	    & DMA_ERRPEND) {
		/*
		 * It would be desirable to set the ATN* line and attempt to
		 * do the whole schmear of INITIATOR DETECTED ERROR here,
		 * but that is too hard to do at present.
		 */
		fas_log(fas, CE_WARN,
		    "Unrecoverable DMA error during selection");
		fas_set_pkt_reason(fas, sp, CMD_TRAN_ERR, 0);

		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_FINISH_SELECT_RESET1_END,
		    "fas_finish_select_end (ACTION_RESET1)");
		return (ACTION_RESET);
	}

	/*
	 * Shut off DMA gate array
	 */
	FAS_FLUSH_DMA(fas);

	/*
	 * Did something respond to selection?
	 */
	if (intr == (FAS_INT_BUS|FAS_INT_FCMP)) {
		/*
		 * We succesfully selected a target (we think).
		 * Now we figure out how botched things are
		 * based upon the kind of selection we were
		 * doing and the state of the step register.
		 */
		switch (step) {
		case FAS_STEP_ARBSEL:
			/*
			 * In this case, we selected the target, but went
			 * neither into MESSAGE OUT nor COMMAND phase.
			 * However, this isn't a fatal error, so we just
			 * drive on.
			 *
			 * This might be a good point to note that we have
			 * a target that appears to not accomodate
			 * disconnecting,
			 * but it really isn't worth the effort to distinguish
			 * such targets fasecially from others.
			 */
			/* FALLTHROUGH */

		case FAS_STEP_SENTID:
			/*
			 * In this case, we selected the target and sent
			 * message byte and have stopped with ATN* still on.
			 * This case should only occur if we use the SELECT
			 * AND STOP command.
			 */
			/* FALLTHROUGH */

		case FAS_STEP_NOTCMD:
			/*
			 * In this case, we either didn't transition to command
			 * phase, or,
			 * if we were using the SELECT WITH ATN3 command,
			 * we possibly didn't send all message bytes.
			 */
			break;

		case FAS_STEP_PCMD:
			/*
			 * In this case, not all command bytes transferred.
			 */
			/* FALLTHROUGH */

		case FAS_STEP_DONE:
			/*
			 * This is the usual 'good' completion point.
			 * If we we sent message byte(s), we subtract
			 * off the number of message bytes that were
			 * ahead of the command.
			 */
			sp->cmd_pkt->pkt_state |= STATE_SENT_CMD;
			break;

		default:
			fas_log(fas, CE_WARN,
			    "bad sequence step (0x%x) in selection", step);
			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_FINISH_SELECT_RESET3_END,
			    "fas_finish_select_end (ACTION_RESET3)");
			return (ACTION_RESET);
		}

		/*
		 * OR in common state...
		 */
		sp->cmd_pkt->pkt_state |= (STATE_GOT_BUS|STATE_GOT_TARGET);

		/*
		 * data pointer initialization has already been done
		 */
		New_state(fas, ACTS_UNKNOWN);
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_FINISH_SELECT_ACTION3_END,
		    "fas_finish_select_end (action3)");
		return (fas_handle_unknown(fas));

	} else if (intr == FAS_INT_DISCON) {
		/*
		 * make sure we negotiate when this target comes
		 * on line later on
		 */
		fas_force_renegotiation(fas, Tgt(sp));

		fas->f_sdtr_sent = fas->f_wdtr_sent = 0;
		sp->cmd_pkt->pkt_state |= STATE_GOT_BUS;

		/*
		 * Set the throttle to DRAIN_THROTTLE to make
		 * sure any disconnected commands will get timed out
		 * incase the drive dies
		 */

		if (fas->f_reset_delay[Tgt(sp)] == 0) {
			fas->f_throttle[sp->cmd_slot] = DRAIN_THROTTLE;
		}

		fas_set_pkt_reason(fas, sp, CMD_INCOMPLETE, 0);

		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_FINISH_SELECT_FINISH_END,
		    "fas_finish_select_end (ACTION_FINISH)");
		return (ACTION_FINISH);
	} else	{
		fas_printstate(fas, "undetermined selection failure");
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_FINISH_SELECT_RESET2_END,
		    "fas_finish_select_end (ACTION_RESET2)");
		return (ACTION_RESET);
	}
	_NOTE(NOT_REACHED)
	/* NOTREACHED */
}

/*
 * a selection got preempted by a reselection; shut down dma
 * and put back cmd in the ready queue unless NOINTR
 */
static int
fas_reselect_preempt(struct fas *fas)
{
	int rval;

	/*
	 * A reselection attempt glotzed our selection attempt.
	 * we put request back in the ready queue
	 */
	struct fas_cmd *sp = fas->f_current_sp;

	/*
	 * Shut off DMA gate array
	 */
	FAS_FLUSH_DMA(fas);

	/*
	 * service the reconnect now and clean up later
	 */
	New_state(fas, STATE_FREE);
	rval = fas_reconnect(fas);

	/*
	 * If selection for a non-tagged command is preempted, the
	 * command could be stuck because throttle was set to DRAIN,
	 * and a disconnected command timeout follows.
	 */
	if ((sp->cmd_pkt_flags & FLAG_TAGMASK) == 0)
		fas->f_throttle[sp->cmd_slot] = 1;

	if ((sp->cmd_flags & CFLAG_CMDPROXY) == 0) {
		fas_remove_cmd(fas, sp, NEW_TIMEOUT);
	}

	/*
	 * if we attempted to renegotiate on this cmd, undo this now
	 */
	if (fas->f_wdtr_sent) {
		fas->f_wide_known &= ~(1<<Tgt(sp));
		fas->f_wdtr_sent = 0;
	}
	if (fas->f_sdtr_sent) {
		fas->f_sync_known &= ~(1<<Tgt(sp));
		fas->f_sdtr_sent = 0;
	}

	fas_head_of_readyQ(fas, sp);

	return (rval);
}

/*
 * Handle the reconnection of a target
 */
static int
fas_reconnect(struct fas *fas)
{
	volatile struct fasreg *fasreg = fas->f_reg;
	struct fas_cmd *sp = NULL;
	uchar_t target, lun;
	uchar_t tmp;
	uchar_t slot;
	char *bad_reselect = NULL;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_RECONNECT_START,
	    "fas_reconnect_start");
	EPRINTF("fas_reconnect:\n");

	fas_check_ncmds(fas);

	switch (fas->f_state) {
	default:
		/*
		 * Pick up target id from fifo
		 *
		 * There should only be the reselecting target's id
		 * and an identify message in the fifo.
		 */
		target = fas->f_fifo[0];

		/*
		 * we know the target so update period, conf3,
		 * offset reg, if necessary, and accept the msg
		 */
		FAS_SET_PERIOD_OFFSET_CONF3_REGS(fas, target);

		/*
		 * now we can accept the message. an untagged
		 * target will go immediately into data phase so
		 * the period/offset/conf3 registers need to be
		 * updated before accepting the message
		 */
		fas_reg_cmd_write(fas, CMD_MSG_ACPT);

		if (fas->f_fifolen != 2) {
			bad_reselect = "bad reselect bytes";
			break;
		}

		/*
		 * normal initial reconnect; we get another interrupt later
		 * for the tag
		 */
		New_state(fas, ACTS_RESEL);

		if (fas->f_stat & FAS_STAT_PERR) {
			break;
		}

		/*
		 * Check sanity of message.
		 */
		tmp = fas->f_fifo[1];
		fas->f_last_msgin = tmp;

		if (!(IS_IDENTIFY_MSG(tmp)) || (tmp & INI_CAN_DISCON)) {
			bad_reselect = "bad identify msg";
			break;
		}

		lun = tmp & (NLUNS_PER_TARGET-1);

		EPRINTF2("fas_reconnect: target=%x, idmsg=%x\n",
		    target, tmp);

		fas->f_resel_slot = slot = (target * NLUNS_PER_TARGET) | lun;

		fas_reg_write(fas, (uchar_t *)&fasreg->fas_busid,
		    (target & 0xf) | FAS_BUSID_ENCODID |
		    FAS_BUSID_32BIT_COUNTER);

		/*
		 * If tag queueing in use, DMA in tag.
		 * Otherwise, we're ready to go.
		 * if tag 0 slot is non-empty, a non-tagged cmd is
		 * reconnecting
		 */
		if (TAGGED(target) && fas->f_tcmds[slot] &&
		    (fas->f_active[slot]->f_slot[0] == NULL)) {
			volatile uchar_t *c =
			    (uchar_t *)fas->f_cmdarea;

			/*
			 * If we've been doing tagged queueing and this
			 * request doesn't  do it,
			 * maybe it was disabled for this one.	This is rather
			 * dangerous as it blows all pending tagged cmds away.
			 * But if target is confused, then we'll blow up
			 * shortly.
			 */
			*c++ = INVALID_MSG;
			*c   = INVALID_MSG;

			FAS_DMA_WRITE_SETUP(fas, 2,
			    fas->f_dmacookie.dmac_address);

			/*
			 * For tagged queuing, we should still be in msgin
			 * phase.
			 * If not, then either we aren't running tagged
			 * queueing like we thought or the target died.
			 */
			if (INTPENDING(fas) == 0) {
				EPRINTF1("slow reconnect, slot=%x\n", slot);
				TRACE_0(TR_FAC_SCSI_FAS,
				    TR_FAS_RECONNECT_RETURN1_END,
				    "fas_reconnect_end (_RETURN1)");
				return (ACTION_RETURN);
			}

			fas->f_stat = fas_reg_read(fas, &fasreg->fas_stat);
			fas->f_intr = fas_reg_read(fas, &fasreg->fas_intr);
			if (fas->f_intr & (FAS_INT_ILLEGAL | FAS_INT_RESET)) {
				return (fas_illegal_cmd_or_bus_reset(fas));
			}

			if ((fas->f_stat & FAS_PHASE_MASK) !=
			    FAS_PHASE_MSG_IN) {
				bad_reselect = "not in msgin phase";
				break;
			}

			if (fas->f_intr & FAS_INT_DISCON) {
				bad_reselect = "unexpected bus free";
				break;
			}
		} else {
			fas->f_current_sp = sp = fas->f_active[slot]->f_slot[0];
			break;
		}
		/*FALLTHROUGH*/

	case ACTS_RESEL:
		{
			volatile uchar_t *c =
			    (uchar_t *)fas->f_cmdarea;
			struct f_slots *tag_slots;
			int id, tag;
			uint_t i;

			slot = fas->f_resel_slot;
			target = slot/NLUNS_PER_TARGET;

			if ((fas->f_stat & FAS_PHASE_MASK) !=
			    FAS_PHASE_MSG_IN) {
				IPRINTF1("no tag for slot %x\n", slot);
				if (fas->f_intr & ~(FAS_INT_BUS |
				    FAS_INT_FCMP)) {
					New_state(fas, ACTS_UNKNOWN);
					TRACE_0(TR_FAC_SCSI_FAS,
					    TR_FAS_RECONNECT_PHASEMANAGE_END,
					    "fas_reconnect_end (_PHASEMANAGE)");
					return (ACTION_PHASEMANAGE);
				} else {
					bad_reselect = "not in msgin phase";
					break;
				}
			}
			fas_reg_cmd_write(fas, CMD_TRAN_INFO|CMD_DMA);
			fas_dma_reg_write(fas, &fas->f_dma->dma_csr,
			    fas->f_dma_csr);

			fas_reg_cmd_write(fas, CMD_MSG_ACPT);

			for (i = 0; i < (uint_t)RECONNECT_TAG_RCV_TIMEOUT;
			    i++) {
				/*
				 * timeout is not very accurate but this
				 * should take no time at all
				 */
				if (INTPENDING(fas)) {
					fas->f_stat = fas_reg_read(fas,
					    (uchar_t *)&fas->f_reg->fas_stat);
					fas->f_intr = fas_reg_read(fas,
					    (uchar_t *)&fas->f_reg->fas_intr);
					if (fas->f_intr & (FAS_INT_RESET |
					    FAS_INT_ILLEGAL)) {
						return (
						    fas_illegal_cmd_or_bus_reset
						    (fas));
					}
					if (fas->f_intr & FAS_INT_FCMP) {
						break;
					}
				}
			}

			if (i == (uint_t)RECONNECT_TAG_RCV_TIMEOUT) {
				bad_reselect = "timeout on receiving tag msg";
				break;
			}

			FAS_FLUSH_DMA(fas);

			/*
			 * we should really do a sync here but that
			 * hurts performance too much; we'll just hang
			 * around till the tag byte flips
			 * This is necessary on any system with an
			 * XBox
			 */
			if (*c == INVALID_MSG) {
				EPRINTF(
				    "fas_reconnect: invalid msg, polling\n");
				for (i = 0; i < 1000000; i++) {
					if (*c != INVALID_MSG)
						break;
				}
			}

			if (fas->f_stat & FAS_STAT_PERR) {
				break;
			}

			if ((fas->f_stat & FAS_STAT_XZERO) == 0 ||
			    (id = *c++) < MSG_SIMPLE_QTAG ||
			    id > MSG_ORDERED_QTAG) {
				/*
				 * Target agreed to do tagged queueing
				 * and lied!
				 * This problem implies the drive firmware is
				 * broken.
				 */
				bad_reselect = "botched tag";
				break;
			}
			tag = *c;

			/* Set ptr to reconnecting scsi pkt */
			tag_slots = fas->f_active[slot];
			if (tag_slots != NULL) {
				sp = tag_slots->f_slot[tag];
			} else {
				bad_reselect = "Invalid tag";
				break;
			}

			fas->f_current_sp = sp;
		}
	}

	if (fas->f_stat & FAS_STAT_PERR) {
		sp = NULL;
		bad_reselect = "Parity error in reconnect msg's";
	}

	if ((sp == NULL ||
#ifdef FAS_TEST
	    (fas_atest_reconn & (1<<Tgt(sp))) ||
#endif
	    (sp->cmd_flags & (CFLAG_CMDDISC|CFLAG_CMDPROXY)) == 0)) {
		/*
		 * this shouldn't really happen, so it is better
		 * to reset the bus; some disks accept the abort
		 * and then still reconnect
		 */
		if (bad_reselect == NULL) {
			bad_reselect = "no command";
		}
#ifdef FAS_TEST
		if (sp && !(fas_atest_reconn & (1<<Tgt(sp))) &&
		    fas_test_stop) {
			debug_enter("bad reconnect");
		} else {
			fas_atest_reconn = 0;
		}
#endif
		goto bad;

	/*
	 *  XXX remove this case or make it an ASSERT
	 */
	} else if (sp->cmd_flags & CFLAG_CMDPROXY) {
		/*
		 * If we got here, we were already attempting to
		 * run a polled proxy command for this target.
		 * Set ATN and, copy in the message, and drive
		 * on (ignoring any parity error on the identify).
		 */
		IPRINTF1("fas_reconnect: fielding proxy cmd for %d\n",
		    target);
		fas_assert_atn(fas);
		fas->f_omsglen = sp->cmd_cdb[FAS_PROXY_DATA];
		tmp = 0;
		while (tmp < fas->f_omsglen) {
			fas->f_cur_msgout[tmp] =
			    sp->cmd_cdb[FAS_PROXY_DATA+1+tmp];
			tmp++;
		}
		sp->cmd_cdb[FAS_PROXY_RESULT] = FALSE;

		/*
		 * pretend that the disconnected cmd is still disconnected
		 * (this prevents ndisc from going negative)
		 */
		fas->f_ndisc++;
		ASSERT((fas->f_ncmds >= 0) && (fas->f_ndisc >= 0));
		ASSERT(fas->f_ncmds >= fas->f_ndisc);
	}

	ASSERT(fas->f_resel_slot == slot);
	ASSERT(fas->f_ndisc > 0);
	fas->f_ndisc--;
	sp->cmd_flags &= ~CFLAG_CMDDISC;
	New_state(fas, ACTS_UNKNOWN);

	/*
	 * A reconnect may imply a restore pointers operation
	 * Note that some older disks (Micropolis in Pbox) do not
	 * send a save data ptr on disconnect if all data has been
	 * xferred. So, we cannot restore ptrs yet here.
	 */
	if ((sp->cmd_flags & CFLAG_DMAVALID) &&
	    (sp->cmd_data_count != sp->cmd_saved_data_count)) {
		sp->cmd_flags |= CFLAG_RESTORE_PTRS;
	}

	/*
	 * Return to await the FUNCTION COMPLETE interrupt we
	 * should get out of accepting the IDENTIFY message.
	 */
	EPRINTF2("Reconnecting %d.%d\n", target, slot % NLUNS_PER_TARGET);
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_RECONNECT_RETURN2_END,
	    "fas_reconnect_end (_RETURN2)");
	return (ACTION_RETURN);

bad:
	if (sp && (fas->f_stat	& FAS_STAT_PERR)) {
		sp->cmd_pkt->pkt_statistics |= STAT_PERR;
	}
	fas_log(fas, CE_WARN, "target %x: failed reselection (%s)",
	    target, bad_reselect);

#ifdef FASDEBUG
	fas_printstate(fas, "failed reselection");
#endif
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_RECONNECT_RESET5_END,
	    "fas_reconnect_end (_RESET5)");
	return (ACTION_RESET);
}

/*
 * handle unknown bus phase
 * we don't know what to expect so check status register for current
 * phase
 */
int
fas_handle_unknown(struct fas *fas)
{
	TRACE_1(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_UNKNOWN_START,
	    "fas_handle_unknown_start: fas 0x%p", fas);
	EPRINTF("fas_handle_unknown:\n");

	if ((fas->f_intr & FAS_INT_DISCON) == 0) {
		/*
		 * we call actions here rather than returning to phasemanage
		 * (this is the most frequently called action)
		 */
		switch (fas->f_stat & FAS_PHASE_MASK) {
		case FAS_PHASE_DATA_IN:
		case FAS_PHASE_DATA_OUT:
			New_state(fas, ACTS_DATA);
			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_UNKNOWN_PHASE_DATA_END,
			    "fas_handle_unknown_end (phase_data)");
			return (fas_handle_data_start(fas));

		case FAS_PHASE_MSG_OUT:
			New_state(fas, ACTS_MSG_OUT);
			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_UNKNOWN_PHASE_MSG_OUT_END,
			    "fas_handle_unknown_end (phase_msg_out)");
			return (fas_handle_msg_out_start(fas));

		case FAS_PHASE_MSG_IN:
			New_state(fas, ACTS_MSG_IN);
			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_UNKNOWN_PHASE_MSG_IN_END,
			    "fas_handle_unknown_end (phase_msg_in)");
			return (fas_handle_msg_in_start(fas));

		case FAS_PHASE_STATUS:
			fas_reg_cmd_write(fas, CMD_FLUSH);
#ifdef	FAS_TEST
			if (fas_ptest_status & (1<<Tgt(fas->f_current_sp))) {
				fas_assert_atn(fas);
			}
#endif	/* FAS_TEST */

			fas_reg_cmd_write(fas, CMD_COMP_SEQ);
			New_state(fas, ACTS_C_CMPLT);

			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_UNKNOWN_PHASE_STATUS_END,
			    "fas_handle_unknown_end (phase_status)");
			return (fas_handle_c_cmplt(fas));

		case FAS_PHASE_COMMAND:
			New_state(fas, ACTS_CMD_START);
			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_UNKNOWN_PHASE_CMD_END,
			    "fas_handle_unknown_end (phase_cmd)");
			return (fas_handle_cmd_start(fas));
		}

		fas_printstate(fas, "Unknown bus phase");
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_UNKNOWN_RESET_END,
		    "fas_handle_unknown_end (reset)");
		return (ACTION_RESET);

	} else {
		/*
		 * Okay. What to do now? Let's try (for the time being)
		 * assuming that the target went south and dropped busy,
		 * as a disconnect implies that either we received
		 * a completion or a disconnect message, or that we
		 * had sent an ABORT OPERATION or BUS DEVICE RESET
		 * message. In either case, we expected the disconnect
		 * and should have fielded it elsewhere.
		 *
		 * If we see a chip disconnect here, this is an unexpected
		 * loss of BSY*. Clean up the state of the chip and return.
		 *
		 */
		int msgout = fas->f_cur_msgout[0];
		struct fas_cmd *sp = fas->f_current_sp;
		int target = Tgt(sp);

		if (msgout == MSG_HEAD_QTAG || msgout == MSG_SIMPLE_QTAG) {
			msgout = fas->f_cur_msgout[2];
		}
		EPRINTF4("msgout: %x %x %x, last_msgout=%x\n",
		    fas->f_cur_msgout[0], fas->f_cur_msgout[1],
		    fas->f_cur_msgout[2], fas->f_last_msgout);

		if (msgout == MSG_ABORT || msgout == MSG_ABORT_TAG ||
		    msgout == MSG_DEVICE_RESET) {
			IPRINTF2("Successful %s message to target %d\n",
			    scsi_mname(msgout), Tgt(sp));
			if (sp->cmd_flags & CFLAG_CMDPROXY) {
				sp->cmd_cdb[FAS_PROXY_RESULT] = TRUE;
			}
			if (msgout == MSG_ABORT || msgout == MSG_ABORT_TAG) {
				fas->f_abort_msg_sent++;
				if ((sp->cmd_flags & CFLAG_CMDPROXY) == 0) {
					fas_set_pkt_reason(fas, sp,
					    CMD_ABORTED, STAT_ABORTED);
				}
			} else if (msgout == MSG_DEVICE_RESET) {
				fas->f_reset_msg_sent++;
				if ((sp->cmd_flags & CFLAG_CMDPROXY) == 0) {
					fas_set_pkt_reason(fas, sp,
					    CMD_RESET, STAT_DEV_RESET);
				}
				fas_force_renegotiation(fas, target);
			}
		} else {
			if ((fas->f_last_msgout == MSG_EXTENDED) &&
			    (fas->f_last_msgin == MSG_REJECT)) {
				/*
				 * the target rejected the negotiations,
				 * so resubmit again (no_sync/no_wide
				 * is now set)
				 */
				New_state(fas, STATE_FREE);
				fas_reg_cmd_write(fas, CMD_EN_RESEL);
				fas_remove_cmd(fas, sp, NEW_TIMEOUT);
				fas_decrement_ncmds(fas, sp);
				fas_check_ncmds(fas);
				sp->cmd_flags &= ~CFLAG_TRANFLAG;
				(void) fas_accept_pkt(fas, sp,	NO_TRAN_BUSY);
				fas_check_ncmds(fas);
				TRACE_0(TR_FAC_SCSI_FAS,
				    TR_FAS_HANDLE_UNKNOWN_INT_DISCON_END,
				    "fas_handle_unknown_end (int_discon)");
				return (ACTION_SEARCH);

			} else if (fas->f_last_msgout == MSG_EXTENDED)	{
				/*
				 * target dropped off the bus during
				 * negotiations
				 */
				fas_reset_sync_wide(fas);
				fas->f_sdtr_sent = fas->f_wdtr_sent = 0;
			}

			fas_set_pkt_reason(fas, sp, CMD_UNX_BUS_FREE, 0);
#ifdef FASDEBUG
			fas_printstate(fas, "unexpected bus free");
#endif
		}
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_UNKNOWN_INT_DISCON_END,
		    "fas_handle_unknown_end (int_discon)");
		return (ACTION_FINISH);
	}
	_NOTE(NOT_REACHED)
	/* NOTREACHED */
}

/*
 * handle target disconnecting
 */
static int
fas_handle_clearing(struct fas *fas)
{
	struct fas_cmd *sp = fas->f_current_sp;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_CLEARING_START,
	    "fas_handle_clearing_start");
	EPRINTF("fas_handle_clearing:\n");

	if (fas->f_laststate == ACTS_C_CMPLT ||
	    fas->f_laststate == ACTS_MSG_IN_DONE) {
		if (INTPENDING(fas)) {
			volatile struct fasreg *fasreg = fas->f_reg;

			fas->f_stat = fas_reg_read(fas,
			    (uchar_t *)&fasreg->fas_stat);
			fas->f_intr = fas_reg_read(fas,
			    (uchar_t *)&fasreg->fas_intr);
			if (fas->f_intr & (FAS_INT_RESET | FAS_INT_ILLEGAL)) {
				return (fas_illegal_cmd_or_bus_reset(fas));
			}
		} else {
			/*
			 * change e_laststate for the next time around
			 */
			fas->f_laststate = ACTS_CLEARING;
			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_CLEARING_RETURN1_END,
			    "fas_handle_clearing_end (ACTION_RETURN1)");
			return (ACTION_RETURN);
		}
	}

	if (fas->f_intr == FAS_INT_DISCON) {
		/*
		 * At this point the FAS chip has disconnected. The bus should
		 * be either quiet or someone may be attempting a reselection
		 * of us (or somebody else). Call the routine that sets the
		 * chip back to a correct and known state.
		 * If the last message in was a disconnect, search
		 * for new work to do, else return to call fas_finish()
		 */
		fas->f_last_msgout = 0xff;
		fas->f_omsglen = 0;
		if (fas->f_last_msgin == MSG_DISCONNECT) {

			fas_reg_cmd_write(fas, CMD_EN_RESEL);

			New_state(fas, STATE_FREE);

			ASSERT(fas->f_current_sp != NULL);
			EPRINTF2("disconnecting %d.%d\n", Tgt(sp), Lun(sp));

			sp->cmd_pkt->pkt_statistics |= STAT_DISCON;
			sp->cmd_flags |= CFLAG_CMDDISC;
			if ((sp->cmd_flags & CFLAG_CMDPROXY) == 0) {
				fas->f_ndisc++;
			}
			ASSERT((fas->f_ncmds >= 0) && (fas->f_ndisc >= 0));
			ASSERT(fas->f_ncmds >= fas->f_ndisc);

			fas->f_current_sp = NULL;

			/*
			 * start a cmd here to save time
			 */
			if ((fas->f_ncmds > fas->f_ndisc) && fas_ustart(fas)) {
				TRACE_0(TR_FAC_SCSI_FAS,
				    TR_FAS_HANDLE_CLEARING_RETURN2_END,
				    "fas_handle_clearing_end (ACTION_RETURN2)");
				return (ACTION_RETURN);
			}


			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_CLEARING_RETURN3_END,
			    "fas_handle_clearing_end (ACTION_RETURN3)");
			return (ACTION_RETURN);
		} else {
			TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_CLEARING_END,
			    "fas_handle_clearing_end");
			return (fas_finish(fas));
		}
	} else {
		/*
		 * If the target didn't disconnect from the
		 * bus, that is a gross fatal error.
		 * XXX this can be caused by asserting ATN
		 * XXX check bus phase and if msgout, send a message
		 */
		fas_log(fas, CE_WARN,
		    "Target %d didn't disconnect after sending %s",
		    Tgt(sp), scsi_mname(fas->f_last_msgin));

		fas_set_pkt_reason(fas, sp, CMD_TRAN_ERR, 0);

#ifdef FASDEBUG
		IPRINTF4("msgout: %x %x %x, last_msgout=%x\n",
		    fas->f_cur_msgout[0], fas->f_cur_msgout[1],
		    fas->f_cur_msgout[2], fas->f_last_msgout);
		IPRINTF1("last msgin=%x\n", fas->f_last_msgin);
#endif
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_CLEARING_ABORT_END,
		    "fas_handle_clearing_end (ACTION_ABORT_CURCMD)");
		return (ACTION_ABORT_ALLCMDS);
	}
}

/*
 * handle data phase start
 */
static int
fas_handle_data_start(struct fas *fas)
{
	uint64_t end;
	uint32_t amt;
	struct fas_cmd *sp = fas->f_current_sp;
	int sending, phase;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_DATA_START,
	    "fas_handle_data_start");
	EPRINTF("fas_handle_data_start:\n");

	if ((sp->cmd_flags & CFLAG_DMAVALID) == 0) {
		fas_printstate(fas, "unexpected data phase");
bad:
		fas_set_pkt_reason(fas, sp, CMD_TRAN_ERR, 0);

		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_DATA_ABORT1_END,
		    "fas_handle_data_end (ACTION_ABORT_CURCMD1)");
		return (ACTION_ABORT_CURCMD);
	} else {
		sending = (sp->cmd_flags & CFLAG_DMASEND)? 1 : 0;
	}

	if (sp->cmd_flags & CFLAG_RESTORE_PTRS) {
		if (fas_restore_pointers(fas, sp)) {
			return (ACTION_ABORT_CURCMD);
		}
		sp->cmd_flags &= ~CFLAG_RESTORE_PTRS;
	}

	/*
	 * And make sure our DMA pointers are in good shape.
	 *
	 * Because SCSI is SCSI, the current DMA pointer has got to be
	 * greater than or equal to our DMA base address. All other cases
	 * that might have affected this always set curaddr to be >=
	 * to the DMA base address.
	 */
	ASSERT(sp->cmd_cur_addr >= sp->cmd_dmacookie.dmac_address);
	end = (uint64_t)sp->cmd_dmacookie.dmac_address +
	    (uint64_t)sp->cmd_dmacookie.dmac_size;

	DPRINTF5(
	    "cmd_data_count=%x, dmacount=%x, curaddr=%x, end=%"
	    PRIx64 ", nwin=%x\n",
	    sp->cmd_data_count, sp->cmd_dmacount, sp->cmd_cur_addr, end,
	    sp->cmd_nwin);
	DPRINTF2("dmac_address = %x, dmac_size=%lx\n",
	    sp->cmd_dmacookie.dmac_address, sp->cmd_dmacookie.dmac_size);

	if (sp->cmd_cur_addr >= end) {
		if (fas_next_window(fas, sp, end)) {
			goto bad;
		}
		end = (uint64_t)sp->cmd_dmacookie.dmac_address +
		    (uint64_t)sp->cmd_dmacookie.dmac_size;
		DPRINTF2("dmac_address=%x, dmac_size=%lx\n",
		    sp->cmd_dmacookie.dmac_address,
		    sp->cmd_dmacookie.dmac_size);
	}

	amt = end - sp->cmd_cur_addr;
	if (fas->f_dma_attr->dma_attr_count_max < amt) {
		amt = fas->f_dma_attr->dma_attr_count_max;
	}
	DPRINTF3("amt=%x, end=%lx, cur_addr=%x\n", amt, end, sp->cmd_cur_addr);

#ifdef FASDEBUG
	/*
	 * Make sure that we don't cross a boundary we can't handle
	 */
	end = (uint64_t)sp->cmd_cur_addr + (uint64_t)amt - 1;
	if ((end & ~fas->f_dma_attr->dma_attr_seg) !=
	    (sp->cmd_cur_addr & ~fas->f_dma_attr->dma_attr_seg)) {
		EPRINTF3("curaddr %x curaddr+amt %" PRIx64
		    " cntr_max %" PRIx64 "\n",
		    sp->cmd_cur_addr, end, fas->f_dma_attr->dma_attr_seg);
		amt = (end & ~fas->f_dma_attr->dma_attr_seg) - sp->cmd_cur_addr;
		if (amt == 0 || amt > fas->f_dma_attr->dma_attr_count_max) {
			fas_log(fas, CE_WARN, "illegal dma boundary? %x", amt);
			goto bad;
		}
	}
#endif

	end = (uint64_t)sp->cmd_dmacookie.dmac_address +
	    (uint64_t)sp->cmd_dmacookie.dmac_size -
	    (uint64_t)sp->cmd_cur_addr;
	if (amt > end) {
		EPRINTF4("ovflow amt %x s.b. %" PRIx64 " curaddr %x count %x\n",
		    amt, end, sp->cmd_cur_addr, sp->cmd_dmacount);
		amt = (uint32_t)end;
	}

	fas->f_lastcount = amt;

	EPRINTF4("%d.%d cmd 0x%x to xfer %x\n", Tgt(sp), Lun(sp),
	    sp->cmd_pkt->pkt_cdbp[0], amt);

	phase = fas->f_stat & FAS_PHASE_MASK;

	if ((phase == FAS_PHASE_DATA_IN) && !sending) {
		FAS_DMA_WRITE(fas, amt, sp->cmd_cur_addr,
		    CMD_TRAN_INFO|CMD_DMA);
	} else if ((phase == FAS_PHASE_DATA_OUT) && sending) {
		FAS_DMA_READ(fas, amt, sp->cmd_cur_addr, amt,
		    CMD_TRAN_INFO|CMD_DMA);
	} else {
		fas_log(fas, CE_WARN,
		    "unwanted data xfer direction for Target %d", Tgt(sp));
		fas_set_pkt_reason(fas, sp, CMD_DMA_DERR, 0);
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_DATA_ABORT2_END,
		    "fas_handle_data_end (ACTION_ABORT_CURCMD2)");
		return (ACTION_ABORT_CURCMD);
	}

#ifdef	FAS_TEST
	if (!sending && (fas_ptest_data_in & (1<<Tgt(sp)))) {
		fas_assert_atn(fas);
	}
#endif	/* FAS_TEST */

	New_state(fas, ACTS_DATA_DONE);

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_DATA_END,
	    "fas_handle_data_end (ACTION_RETURN)");
	return (ACTION_RETURN);
}

static int
fas_handle_data_done(struct fas *fas)
{
	volatile struct fasreg *fasreg = fas->f_reg;
	volatile struct dma *dmar = fas->f_dma;
	struct fas_cmd *sp = fas->f_current_sp;
	uint32_t xfer_amt;
	char was_sending;
	uchar_t stat, fifoamt, tgt;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_DATA_DONE_START,
	    "fas_handle_data_done_start");
	EPRINTF("fas_handle_data_done\n");

	tgt = Tgt(sp);
	stat = fas->f_stat;
	was_sending = (sp->cmd_flags & CFLAG_DMASEND) ? 1 : 0;

	/*
	 * Check for DMA errors (parity or memory fault)
	 */
	if ((fas->f_dma_csr = fas_dma_reg_read(fas, &dmar->dma_csr)) &
	    DMA_ERRPEND) {
		/*
		 * It would be desirable to set the ATN* line and attempt to
		 * do the whole schmear of INITIATOR DETECTED ERROR here,
		 * but that is too hard to do at present.
		 */
		fas_log(fas, CE_WARN, "Unrecoverable DMA error on dma %s",
		    (was_sending) ? "send" : "receive");
		fas_set_pkt_reason(fas, sp, CMD_TRAN_ERR, 0);
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_DATA_DONE_RESET_END,
		    "fas_handle_data_done_end (ACTION_RESET)");
		return (ACTION_RESET);
	}

	/*
	 * Data Receive conditions:
	 *
	 * Check for parity errors. If we have a parity error upon
	 * receive, the FAS chip has asserted ATN* for us already.
	 */
	if (!was_sending) {
#ifdef	FAS_TEST
		if (fas_ptest_data_in & (1<<tgt)) {
			fas_ptest_data_in = 0;
			stat |= FAS_STAT_PERR;
			if (fas_test_stop > 1) {
				debug_enter("ptest_data_in");
			}
		}
#endif	/* FAS_TEST */
		if (stat & FAS_STAT_PERR) {
			fas_log(fas, CE_WARN,
			    "SCSI bus DATA IN phase parity error");
			fas->f_cur_msgout[0] = MSG_INITIATOR_ERROR;
			fas->f_omsglen = 1;
			sp->cmd_pkt->pkt_statistics |= STAT_PERR;
			sp->cmd_pkt->pkt_reason = CMD_TRAN_ERR;
		}
	}

	FAS_FLUSH_DMA(fas);

	/*
	 * Check to make sure we're still connected to the target.
	 * If the target dropped the bus, that is a fatal error.
	 * We don't even attempt to count what we were transferring
	 * here. Let fas_handle_unknown clean up for us.
	 */
	if (fas->f_intr != FAS_INT_BUS) {
		New_state(fas, ACTS_UNKNOWN);
		TRACE_0(TR_FAC_SCSI_FAS,
		    TR_FAS_HANDLE_DATA_DONE_PHASEMANAGE_END,
		    "fas_handle_data_done_end (ACTION_PHASEMANAGE)");
		return (ACTION_PHASEMANAGE);
	}

	/*
	 * Figure out how far we got.
	 * Latch up fifo amount first and double if wide has been enabled
	 */
	fifoamt = FIFO_CNT(fas);
	if (fas->f_wide_enabled & (1<<tgt)) {
		fifoamt = fifoamt << 1;
	}

	if (stat & FAS_STAT_XZERO) {
		xfer_amt = fas->f_lastcount;
	} else {
		GET_FAS_COUNT(fasreg, xfer_amt);
		xfer_amt = fas->f_lastcount - xfer_amt;
	}
	DPRINTF4("fifoamt=%x, xfer_amt=%x, lastcount=%x, stat=%x\n",
	    fifoamt, xfer_amt, fas->f_lastcount, stat);


	/*
	 * Unconditionally knock off by the amount left
	 * in the fifo if we were sending out the SCSI bus.
	 *
	 * If we were receiving from the SCSI bus, believe
	 * what the chip told us (either XZERO or by the
	 * value calculated from the counter register).
	 * The reason we don't look at the fifo for
	 * incoming data is that in synchronous mode
	 * the fifo may have further data bytes, and
	 * for async mode we assume that all data in
	 * the fifo will have been transferred before
	 * the fas asserts an interrupt.
	 */
	if (was_sending) {
		xfer_amt -= fifoamt;
	}

#ifdef FASDEBUG
	{
	int phase = stat & FAS_PHASE_MASK;
	fas->f_stat2 = fas_reg_read(fas,
	    (uchar_t *)&fasreg->fas_stat2);

	if (((fas->f_stat & FAS_STAT_XZERO) == 0) &&
	    (phase != FAS_PHASE_DATA_IN) &&
	    (phase != FAS_PHASE_DATA_OUT) &&
	    (fas->f_stat2 & FAS_STAT2_ISHUTTLE)) {
		fas_log(fas, CE_WARN,
		    "input shuttle not empty at end of data phase");
		fas_set_pkt_reason(fas, sp, CMD_TRAN_ERR, 0);
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_DATA_DONE_RESET_END,
		    "fas_handle_data_done_end (ACTION_RESET)");
		return (ACTION_RESET);
	}
}
#endif /* FASDEBUG */

	/*
	 * If this was a synchronous transfer, flag it.
	 * Also check for the errata condition of long
	 * last REQ/ pulse for some synchronous targets
	 */
	if (fas->f_offset[tgt]) {
		/*
		 * flag that a synchronous data xfer took place
		 */
		sp->cmd_pkt->pkt_statistics |= STAT_SYNC;

		if (was_sending)
			fas_reg_cmd_write(fas, CMD_FLUSH);
	} else {
		/*
		 * If we aren't doing Synchronous Data Transfers,
		 * definitely offload the fifo.
		 */
		fas_reg_cmd_write(fas, CMD_FLUSH);
	}

	/*
	 * adjust pointers...
	 */
	DPRINTF3("before:cmd_data_count=%x, cmd_cur_addr=%x, xfer_amt=%x\n",
	    sp->cmd_data_count, sp->cmd_cur_addr, xfer_amt);
	sp->cmd_data_count += xfer_amt;
	sp->cmd_cur_addr += xfer_amt;
	sp->cmd_pkt->pkt_state |= STATE_XFERRED_DATA;
	New_state(fas, ACTS_UNKNOWN);
	DPRINTF3("after:cmd_data_count=%x, cmd_cur_addr=%x, xfer_amt=%x\n",
	    sp->cmd_data_count, sp->cmd_cur_addr, xfer_amt);

	stat &= FAS_PHASE_MASK;
	if (stat == FAS_PHASE_DATA_IN || stat == FAS_PHASE_DATA_OUT) {
		fas->f_state = ACTS_DATA;
		TRACE_0(TR_FAC_SCSI_FAS,
		    TR_FAS_HANDLE_DATA_DONE_ACTION1_END,
		    "fas_handle_data_done_end (action1)");
		return (fas_handle_data_start(fas));
	}

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_DATA_DONE_ACTION2_END,
	    "fas_handle_data_done_end (action2)");
	return (fas_handle_unknown(fas));
}

static char msginperr[] = "SCSI bus MESSAGE IN phase parity error";

static int
fas_handle_c_cmplt(struct fas *fas)
{
	struct fas_cmd *sp = fas->f_current_sp;
	volatile struct fasreg *fasreg = fas->f_reg;
	uchar_t sts, msg, intr, perr;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_C_CMPLT_START,
	    "fas_handle_c_cmplt_start");
	EPRINTF("fas_handle_c_cmplt:\n");


	/*
	 * if target is fast, we can get cmd. completion by the time we get
	 * here. Otherwise, we'll have to taken an interrupt.
	 */
	if (fas->f_laststate == ACTS_UNKNOWN) {
		if (INTPENDING(fas)) {
			fas->f_stat = fas_reg_read(fas,
			    (uchar_t *)&fasreg->fas_stat);
			intr = fas_reg_read(fas, (uchar_t *)&fasreg->fas_intr);
			fas->f_intr = intr;
			if (fas->f_intr & (FAS_INT_RESET | FAS_INT_ILLEGAL)) {
				return (fas_illegal_cmd_or_bus_reset(fas));
			}
		} else {
			/*
			 * change f_laststate for the next time around
			 */
			fas->f_laststate = ACTS_C_CMPLT;
			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_C_CMPLT_RETURN1_END,
			    "fas_handle_c_cmplt_end (ACTION_RETURN1)");
			return (ACTION_RETURN);
		}
	} else {
		intr = fas->f_intr;
	}

#ifdef	FAS_TEST
	if (fas_ptest_status & (1<<Tgt(sp))) {
		fas_ptest_status = 0;
		fas->f_stat |= FAS_STAT_PERR;
		if (fas_test_stop > 1) {
			debug_enter("ptest_status");
		}
	} else if ((fas_ptest_msgin & (1<<Tgt(sp))) && fas_ptest_msg == 0) {
		fas_ptest_msgin = 0;
		fas_ptest_msg = -1;
		fas->f_stat |= FAS_STAT_PERR;
		if (fas_test_stop > 1) {
			debug_enter("ptest_completion");
		}
	}
#endif	/* FAS_TEST */

	if (intr == FAS_INT_DISCON) {
		New_state(fas, ACTS_UNKNOWN);
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_C_CMPLT_ACTION1_END,
		    "fas_handle_c_cmplt_end (action1)");
		return (fas_handle_unknown(fas));
	}

	if ((perr = (fas->f_stat & FAS_STAT_PERR)) != 0) {
		fas_assert_atn(fas);
		sp->cmd_pkt->pkt_statistics |= STAT_PERR;
	}

	/*
	 * do a msg accept now and read the fifo data
	 */
	if (intr & FAS_INT_FCMP) {
		/*
		 * The FAS manuals state that this sequence completes
		 * with a BUS SERVICE interrupt if just the status
		 * byte was received, else a FUNCTION COMPLETE interrupt
		 * if both status and a message was received.
		 *
		 * if we give the MSG_ACT before reading the msg byte
		 * we get the status byte again and if the status is zero
		 * then we won't detect a failure
		 */
		*(sp->cmd_pkt->pkt_scbp) =
		    sts = fas_reg_read(fas, (uchar_t *)&fasreg->fas_fifo_data);
		fas->f_last_msgin = fas->f_imsgarea[0] =
		    msg = fas_reg_read(fas, (uchar_t *)&fasreg->fas_fifo_data);

		fas_reg_cmd_write(fas, CMD_MSG_ACPT);
		sp->cmd_pkt->pkt_state |= STATE_GOT_STATUS;

		/*
		 * The manuals also state that ATN* is asserted if
		 * bad parity is detected.
		 *
		 * The one case that we cannot handle is where we detect
		 * bad parity for the status byte, but the target refuses
		 * to go to MESSAGE OUT phase right away. This means that
		 * if that happens, we will misconstrue the parity error
		 * to be for the completion message, not the status byte.
		 */
		if (perr) {
			fas_log(fas, CE_WARN, msginperr);
			sp->cmd_pkt->pkt_statistics |= STAT_PERR;

			fas->f_cur_msgout[0] = MSG_MSG_PARITY;
			fas->f_omsglen = 1;
			New_state(fas, ACTS_UNKNOWN);
			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_C_CMPLT_ACTION5_END,
			    "fas_handle_c_cmplt_end (action5)");
			return (ACTION_RETURN);
		}

	} else if (intr == FAS_INT_BUS) {
		/*
		 * We only got the status byte.
		 */
		sts = fas_reg_read(fas, (uchar_t *)&fasreg->fas_fifo_data);
		sp->cmd_pkt->pkt_state |= STATE_GOT_STATUS;
		*(sp->cmd_pkt->pkt_scbp) = sts;
		msg = INVALID_MSG;

		IPRINTF1("fas_handle_cmd_cmplt: sts=%x, no msg byte\n", sts);

		if (perr) {
			/*
			 * If we get a parity error on a status byte
			 * assume that it was a CHECK CONDITION
			 */
			sts = STATUS_CHECK;
			fas_log(fas, CE_WARN,
			    "SCSI bus STATUS phase parity error");
			fas->f_cur_msgout[0] = MSG_INITIATOR_ERROR;
			fas->f_omsglen = 1;
			New_state(fas, ACTS_UNKNOWN);
			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_C_CMPLT_ACTION5_END,
			    "fas_handle_c_cmplt_end (action5)");
			return (fas_handle_unknown(fas));
		}

	} else {
		msg = sts = INVALID_MSG;
		IPRINTF("fas_handle_cmd_cmplt: unexpected intr\n");
		New_state(fas, ACTS_UNKNOWN);
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_C_CMPLT_ACTION2_END,
		    "fas_handle_c_cmplt_end (action2)");
		return (fas_handle_unknown(fas));
	}

	EPRINTF2("fas_handle_c_cmplt: status=%x, msg=%x\n", sts, msg);

	EPRINTF1("Completion Message=%s\n", scsi_mname(msg));
	if (msg == MSG_COMMAND_COMPLETE) {
		/*
		 * Actually, if the message was a 'linked command
		 * complete' message, the target isn't going to be
		 * clearing the bus.
		 */
		New_state(fas, ACTS_CLEARING);
		TRACE_0(TR_FAC_SCSI_FAS,
		    TR_FAS_HANDLE_C_CMPLT_ACTION4_END,
		    "fas_handle_c_cmplt_end (action4)");
		return (fas_handle_clearing(fas));
	} else {
		fas->f_imsglen = 1;
		fas->f_imsgindex = 1;
		New_state(fas, ACTS_MSG_IN_DONE);
		TRACE_0(TR_FAC_SCSI_FAS,
		    TR_FAS_HANDLE_C_CMPLT_ACTION3_END,
		    "fas_handle_c_cmplt_end (action3)");
		return (fas_handle_msg_in_done(fas));
	}
}

/*
 * prepare for accepting a message byte from the fifo
 */
static int
fas_handle_msg_in_start(struct fas *fas)
{
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_MSG_IN_START,
	    "fas_handle_msg_in_start");
	EPRINTF("fas_handle_msg_in_start\n");

	/*
	 * Pick up a message byte.
	 * Clear the FIFO so we
	 * don't get confused.
	 */
	if (!FIFO_EMPTY(fas)) {
		fas_reg_cmd_write(fas, CMD_FLUSH);
	}
	fas_reg_cmd_write(fas, CMD_TRAN_INFO);
	fas->f_imsglen = 1;
	fas->f_imsgindex = 0;
	New_state(fas, ACTS_MSG_IN_DONE);

	/*
	 * give a little extra time by returning to phasemanage
	 */
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_MSG_IN_END,
	    "fas_handle_msg_in_end (ACTION_PHASEMANAGE)");
	return (ACTION_PHASEMANAGE);
}

/*
 * We come here after issuing a MSG_ACCEPT
 * command and are expecting more message bytes.
 * The FAS should be asserting a BUS SERVICE
 * interrupt status, but may have asserted
 * a different interrupt in the case that
 * the target disconnected and dropped BSY*.
 *
 * In the case that we are eating up message
 * bytes (and throwing them away unread) because
 * we have ATN* asserted (we are trying to send
 * a message), we do not consider it an error
 * if the phase has changed out of MESSAGE IN.
 */
static int
fas_handle_more_msgin(struct fas *fas)
{
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_MORE_MSGIN_START,
	    "fas_handle_more_msgin_start");
	EPRINTF("fas_handle_more_msgin\n");

	if (fas->f_intr & FAS_INT_BUS) {
		if ((fas->f_stat & FAS_PHASE_MASK) == FAS_PHASE_MSG_IN) {
			/*
			 * Fetch another byte of a message in.
			 */
			fas_reg_cmd_write(fas, CMD_TRAN_INFO);
			New_state(fas, ACTS_MSG_IN_DONE);
			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_MORE_MSGIN_RETURN1_END,
			    "fas_handle_more_msgin_end (ACTION_RETURN)");
			return (ACTION_RETURN);
		}

		/*
		 * If we were gobbling up a message and we have
		 * changed phases, handle this silently, else
		 * complain. In either case, we return to let
		 * fas_phasemanage() handle things.
		 *
		 * If it wasn't a BUS SERVICE interrupt,
		 * let fas_phasemanage() find out if the
		 * chip disconnected.
		 */
		if (fas->f_imsglen != 0) {
			fas_log(fas, CE_WARN,
			    "Premature end of extended message");
		}
	}
	New_state(fas, ACTS_UNKNOWN);
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_MORE_MSGIN_RETURN2_END,
	    "fas_handle_more_msgin_end (action)");
	return (fas_handle_unknown(fas));
}

static int
fas_handle_msg_in_done(struct fas *fas)
{
	struct fas_cmd *sp = fas->f_current_sp;
	volatile struct fasreg *fasreg = fas->f_reg;
	int sndmsg = 0;
	uchar_t msgin;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_MSG_IN_DONE_START,
	    "fas_handle_msg_in_done_start");
	EPRINTF("fas_handle_msg_in_done:\n");
	if (fas->f_laststate == ACTS_MSG_IN) {
		if (INTPENDING(fas)) {
			fas->f_stat = fas_reg_read(fas,
			    (uchar_t *)&fasreg->fas_stat);
			fas->f_stat2 = fas_reg_read(fas,
			    (uchar_t *)&fasreg->fas_stat2);

			fas_read_fifo(fas);

			fas->f_intr = fas_reg_read(fas,
			    (uchar_t *)&fasreg->fas_intr);
			if (fas->f_intr & (FAS_INT_RESET | FAS_INT_ILLEGAL)) {
				return (fas_illegal_cmd_or_bus_reset(fas));
			}
		} else {
			/*
			 * change f_laststate for the next time around
			 */
			fas->f_laststate = ACTS_MSG_IN_DONE;
			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_MSG_IN_DONE_RETURN1_END,
			    "fas_handle_msg_in_done_end (ACTION_RETURN1)");
			return (ACTION_RETURN);
		}
	}

	/*
	 * the most common case is a disconnect message. we do
	 * a fast path for this condition and if it fails then
	 * we go for the detailed error handling
	 */
#ifndef  FAS_TEST
	if (((fas->f_laststate == ACTS_MSG_IN) ||
	    (fas->f_laststate == ACTS_MSG_IN_DONE)) &&
	    ((fas->f_intr & FAS_INT_DISCON) == 0) &&
	    ((fas->f_stat & FAS_STAT_PERR) == 0) &&
	    ((sp->cmd_pkt_flags & FLAG_NODISCON) == 0)) {

		if ((fas->f_fifolen == 1) &&
		    (fas->f_imsglen == 1) &&
		    (fas->f_fifo[0] == MSG_DISCONNECT)) {

			fas_reg_cmd_write(fas, CMD_MSG_ACPT);
			fas->f_imsgarea[fas->f_imsgindex++] = fas->f_fifo[0];
			fas->f_last_msgin = MSG_DISCONNECT;
			New_state(fas, ACTS_CLEARING);

			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_MSG_IN_DONE_ACTION_END,
			    "fas_handle_msg_in_done_end (action)");

			return (fas_handle_clearing(fas));
		}
	}
#endif	/* not FAS_TEST */

	/*
	 * We can be called here for both the case where
	 * we had requested the FAS chip to fetch a message
	 * byte from the target (at the target's request).
	 * We can also be called in the case where we had
	 * been using the CMD_COMP_SEQ command to pick up
	 * both a status byte and a completion message from
	 * a target, but where the message wasn't one of
	 * COMMAND COMPLETE, LINKED COMMAND COMPLETE, or
	 * LINKED COMMAND COMPLETE (with flag). This is a
	 * legal (albeit extremely unusual) SCSI bus trans-
	 * -ition, so we have to handle it.
	 */
	if (fas->f_laststate != ACTS_C_CMPLT) {
#ifdef	FAS_TEST
reloop:
#endif	/* FAS_TEST */

		if (fas->f_intr & FAS_INT_DISCON) {
			fas_log(fas, CE_WARN,
			    "premature end of input message");
			New_state(fas, ACTS_UNKNOWN);
			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_MSG_IN_DONE_PHASEMANAGE_END,
			    "fas_handle_msg_in_done_end (ACTION_PHASEMANAGE)");
			return (ACTION_PHASEMANAGE);
		}

		/*
		 * Note that if f_imsglen is zero, then we are skipping
		 * input message bytes, so there is no reason to look for
		 * parity errors.
		 */
		if (fas->f_imsglen != 0 && (fas->f_stat & FAS_STAT_PERR)) {
			fas_log(fas, CE_WARN, msginperr);
			sndmsg = MSG_MSG_PARITY;
			sp->cmd_pkt->pkt_statistics |= STAT_PERR;
			fas_reg_cmd_write(fas, CMD_FLUSH);

		} else if ((msgin = fas->f_fifolen) != 1) {

			/*
			 * If we have got more than one or 0 bytes in the fifo,
			 * that is a gross screwup, and we should let the
			 * target know that we have completely fouled up.
			 */
			fas_printf(fas, "fifocount=%x", msgin);
			fas_printstate(fas, "input message botch");
			sndmsg = MSG_INITIATOR_ERROR;
			fas_reg_cmd_write(fas, CMD_FLUSH);
			fas_log(fas, CE_WARN, "input message botch");

		} else if (fas->f_imsglen == 0) {
			/*
			 * If we are in the middle of gobbling up and throwing
			 * away a message (due to a previous message input
			 * error), drive on.
			 */
			msgin = fas_reg_read(fas,
			    (uchar_t *)&fasreg->fas_fifo_data);
			New_state(fas, ACTS_MSG_IN_MORE);

		} else {
			msgin = fas->f_fifo[0];
			fas->f_imsgarea[fas->f_imsgindex++] = msgin;
		}

	} else {
		/*
		 * In this case, we have been called (from
		 * fas_handle_c_cmplt()) with the message
		 * already stored in the message array.
		 */
		msgin = fas->f_imsgarea[0];
	}

	/*
	 * Process this message byte (but not if we are
	 * going to be trying to send back some error
	 * anyway)
	 */
	if (sndmsg == 0 && fas->f_imsglen != 0) {

		if (fas->f_imsgindex < fas->f_imsglen) {

			EPRINTF2("message byte %d: 0x%x\n",
			    fas->f_imsgindex-1,
			    fas->f_imsgarea[fas->f_imsgindex-1]);

			New_state(fas, ACTS_MSG_IN_MORE);

		} else if (fas->f_imsglen == 1) {

#ifdef	FAS_TEST
			if ((fas_ptest_msgin & (1<<Tgt(sp))) &&
			    fas_ptest_msg == msgin) {
				fas_ptest_msgin = 0;
				fas_ptest_msg = -1;
				fas_assert_atn(fas);
				fas->f_stat |= FAS_STAT_PERR;
				fas->f_imsgindex -= 1;
				if (fas_test_stop > 1) {
					debug_enter("ptest msgin");
				}
				goto reloop;
			}
#endif	/* FAS_TEST */

			sndmsg = fas_onebyte_msg(fas);

		} else if (fas->f_imsglen == 2) {
#ifdef	FAS_TEST
			if (fas_ptest_emsgin & (1<<Tgt(sp))) {
				fas_ptest_emsgin = 0;
				fas_assert_atn(fas);
				fas->f_stat |= FAS_STAT_PERR;
				fas->f_imsgindex -= 1;
				if (fas_test_stop > 1) {
					debug_enter("ptest emsgin");
				}
				goto reloop;
			}
#endif	/* FAS_TEST */

			if (fas->f_imsgarea[0] ==  MSG_EXTENDED) {
				static char *tool =
				    "Extended message 0x%x is too long";

				/*
				 * Is the incoming message too long
				 * to be stored in our local array?
				 */
				if ((int)(msgin+2) > IMSGSIZE) {
					fas_log(fas, CE_WARN,
					    tool, fas->f_imsgarea[0]);
					sndmsg = MSG_REJECT;
				} else {
					fas->f_imsglen = msgin + 2;
					New_state(fas, ACTS_MSG_IN_MORE);
				}
			} else {
				sndmsg = fas_twobyte_msg(fas);
			}

		} else {
			sndmsg = fas_multibyte_msg(fas);
		}
	}

	if (sndmsg < 0) {
		/*
		 * If sndmsg is less than zero, one of the subsidiary
		 * routines needs to return some other state than
		 * ACTION_RETURN.
		 */
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_MSG_IN_DONE_SNDMSG_END,
		    "fas_handle_msg_in_done_end (-sndmsg)");
		return (-sndmsg);

	} else if (sndmsg > 0) {
		if (IS_1BYTE_MSG(sndmsg)) {
			fas->f_omsglen = 1;
		}
		fas->f_cur_msgout[0] = (uchar_t)sndmsg;

		/*
		 * The target is not guaranteed to go to message out
		 * phase, period. Moreover, until the entire incoming
		 * message is transferred, the target may (and likely
		 * will) continue to transfer message bytes (which
		 * we will have to ignore).
		 *
		 * In order to do this, we'll go to 'infinite'
		 * message in handling by setting the current input
		 * message length to a sentinel of zero.
		 *
		 * This works regardless of the message we are trying
		 * to send out. At the point in time which we want
		 * to send a message in response to an incoming message
		 * we do not care any more about the incoming message.
		 *
		 * If we are sending a message in response to detecting
		 * a parity error on input, the FAS chip has already
		 * set ATN* for us, but it doesn't hurt to set it here
		 * again anyhow.
		 */
		fas_assert_atn(fas);
		New_state(fas, ACTS_MSG_IN_MORE);
		fas->f_imsglen = 0;
	}

	fas_reg_cmd_write(fas, CMD_FLUSH);

	fas_reg_cmd_write(fas, CMD_MSG_ACPT);

	if ((fas->f_laststate == ACTS_MSG_IN_DONE) &&
	    (fas->f_state == ACTS_CLEARING)) {
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_MSG_IN_DONE_ACTION_END,
		    "fas_handle_msg_in_done_end (action)");
		return (fas_handle_clearing(fas));
	}
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_MSG_IN_DONE_RETURN2_END,
	    "fas_handle_msg_in_done_end (ACTION_RETURN2)");
	return (ACTION_RETURN);
}

static int
fas_onebyte_msg(struct fas *fas)
{
	struct fas_cmd *sp = fas->f_current_sp;
	int msgout = 0;
	uchar_t msgin = fas->f_last_msgin = fas->f_imsgarea[0];
	int tgt = Tgt(sp);

	EPRINTF("fas_onebyte_msg\n");

	if (msgin & MSG_IDENTIFY) {
		/*
		 * How did we get here? We should only see identify
		 * messages on a reconnection, but we'll handle this
		 * fine here (just in case we get this) as long as
		 * we believe that this is a valid identify message.
		 *
		 * For this to be a valid incoming message,
		 * bits 6-4 must must be zero. Also, the
		 * bit that says that I'm an initiator and
		 * can support disconnection cannot possibly
		 * be set here.
		 */

		char garbled = ((msgin & (BAD_IDENTIFY|INI_CAN_DISCON)) != 0);

		fas_log(fas, CE_WARN, "%s message 0x%x from Target %d",
		    garbled ? "Garbled" : "Identify", msgin, tgt);

		if (garbled) {
			/*
			 * If it's a garbled message,
			 * try and tell the target...
			 */
			msgout = MSG_INITIATOR_ERROR;
		} else {
			New_state(fas, ACTS_UNKNOWN);
		}
		return (msgout);

	} else if (IS_2BYTE_MSG(msgin) || IS_EXTENDED_MSG(msgin)) {
		fas->f_imsglen = 2;
		New_state(fas, ACTS_MSG_IN_MORE);
		return (0);
	}

	New_state(fas, ACTS_UNKNOWN);

	switch (msgin) {
	case MSG_DISCONNECT:
		/*
		 * If we 'cannot' disconnect- reject this message.
		 * Note that we only key off of the pkt_flags here-
		 * the FLAG_NODISCON was set in fas_accept_pkt() if
		 * no disconnect was enabled in scsi_options
		 */
		if (sp->cmd_pkt_flags & FLAG_NODISCON) {
			msgout = MSG_REJECT;
			break;
		}
		/* FALLTHROUGH */
	case MSG_COMMAND_COMPLETE:
		fas->f_state = ACTS_CLEARING;
		break;

	case MSG_NOP:
		break;

	/* XXX Make it a MSG_REJECT handler */
	case MSG_REJECT:
	{
		uchar_t reason = 0;
		uchar_t lastmsg = fas->f_last_msgout;
		/*
		 * The target is rejecting the last message we sent.
		 *
		 * If the last message we attempted to send out was an
		 * extended message, we were trying to negotiate sync
		 * xfers- and we're okay.
		 *
		 * Otherwise, a target has rejected a message that
		 * it should have handled. We will abort the operation
		 * in progress and set the pkt_reason value here to
		 * show why we have completed. The process of aborting
		 * may be via a message or may be via a bus reset (as
		 * a last resort).
		 */
		msgout = (TAGGED(tgt)? MSG_ABORT_TAG : MSG_ABORT);

		switch (lastmsg) {
		case MSG_EXTENDED:
			if (fas->f_wdtr_sent) {
				/*
				 * Disable wide, Target rejected
				 * out WDTR message
				 */
				fas_set_wide_conf3(fas, tgt, 0);
				fas->f_nowide |= (1<<tgt);
				fas->f_wdtr_sent = 0;
				/*
				 * we still want to negotiate sync
				 */
				if ((fas->f_nosync & (1<<tgt)) == 0) {
					fas_assert_atn(fas);
					fas_make_sdtr(fas, 0, tgt);
				}
			} else if (fas->f_sdtr_sent) {
				fas_reg_cmd_write(fas, CMD_CLR_ATN);
				fas_revert_to_async(fas, tgt);
				fas->f_nosync |= (1<<tgt);
				fas->f_sdtr_sent = 0;
			}
			msgout = 0;
			break;
		case MSG_NOP:
			reason = CMD_NOP_FAIL;
			break;
		case MSG_INITIATOR_ERROR:
			reason = CMD_IDE_FAIL;
			break;
		case MSG_MSG_PARITY:
			reason = CMD_PER_FAIL;
			break;
		case MSG_REJECT:
			reason = CMD_REJECT_FAIL;
			break;
		/* XXX - abort not good, queue full handling or drain (?) */
		case MSG_SIMPLE_QTAG:
		case MSG_ORDERED_QTAG:
		case MSG_HEAD_QTAG:
			msgout = MSG_ABORT;
			reason = CMD_TAG_REJECT;
			break;
		case MSG_DEVICE_RESET:
			reason = CMD_BDR_FAIL;
			msgout = -ACTION_ABORT_CURCMD;
			break;
		case MSG_ABORT:
		case MSG_ABORT_TAG:
			/*
			 * If an RESET/ABORT OPERATION message is rejected
			 * it is time to yank the chain on the bus...
			 */
			reason = CMD_ABORT_FAIL;
			msgout = -ACTION_ABORT_CURCMD;
			break;
		default:
			if (IS_IDENTIFY_MSG(lastmsg)) {
				if (TAGGED(tgt)) {
					/*
					 * this often happens when the
					 * target rejected our tag
					 */
					reason = CMD_TAG_REJECT;
				} else {
					reason = CMD_ID_FAIL;
				}
			} else {
				reason = CMD_TRAN_ERR;
				msgout = -ACTION_ABORT_CURCMD;
			}

			break;
		}

		if (msgout) {
			fas_log(fas, CE_WARN,
			    "Target %d rejects our message '%s'",
			    tgt, scsi_mname(lastmsg));
			fas_set_pkt_reason(fas, sp, reason, 0);
		}

		break;
	}
	case MSG_RESTORE_PTRS:
		sp->cmd_cdbp = sp->cmd_pkt->pkt_cdbp;
		if (sp->cmd_data_count != sp->cmd_saved_data_count) {
			if (fas_restore_pointers(fas, sp)) {
				msgout = -ACTION_ABORT_CURCMD;
			} else if ((sp->cmd_pkt->pkt_reason & CMD_TRAN_ERR) &&
			    (sp->cmd_pkt->pkt_statistics & STAT_PERR) &&
			    (sp->cmd_cur_win == 0) &&
			    (sp->cmd_data_count == 0)) {
				sp->cmd_pkt->pkt_reason &= ~CMD_TRAN_ERR;
			}
		}
		break;

	case MSG_SAVE_DATA_PTR:
		sp->cmd_saved_data_count = sp->cmd_data_count;
		sp->cmd_saved_win = sp->cmd_cur_win;
		sp->cmd_saved_cur_addr = sp->cmd_cur_addr;
		break;

	/* These don't make sense for us, and	*/
	/* will be rejected			*/
	/*	case MSG_INITIATOR_ERROR	*/
	/*	case MSG_ABORT			*/
	/*	case MSG_MSG_PARITY		*/
	/*	case MSG_DEVICE_RESET		*/
	default:
		msgout = MSG_REJECT;
		fas_log(fas, CE_WARN,
		    "Rejecting message '%s' from Target %d",
		    scsi_mname(msgin), tgt);
		break;
	}

	EPRINTF1("Message in: %s\n", scsi_mname(msgin));

	return (msgout);
}

/*
 * phase handlers that are rarely used
 */
static int
fas_handle_cmd_start(struct fas *fas)
{
	struct fas_cmd *sp = fas->f_current_sp;
	volatile uchar_t *tp = fas->f_cmdarea;
	int i;
	int amt = sp->cmd_cdblen;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_CMD_START_START,
	    "fas_handle_cmd_start_start");
	EPRINTF("fas_handle_cmd: send cmd\n");

	for (i = 0; i < amt; i++) {
		*tp++ = sp->cmd_cdbp[i];
	}
	fas_reg_cmd_write(fas, CMD_FLUSH);

	FAS_DMA_READ(fas, amt, fas->f_dmacookie.dmac_address, amt,
	    CMD_TRAN_INFO|CMD_DMA);
	fas->f_lastcount = amt;

	New_state(fas, ACTS_CMD_DONE);

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_CMD_START_END,
	    "fas_handle_cmd_start_end");
	return (ACTION_RETURN);
}

static int
fas_handle_cmd_done(struct fas *fas)
{
	struct fas_cmd *sp = fas->f_current_sp;
	uchar_t intr = fas->f_intr;
	volatile struct dma *dmar = fas->f_dma;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_CMD_DONE_START,
	    "fas_handle_cmd_done_start");
	EPRINTF("fas_handle_cmd_done\n");

	/*
	 * We should have gotten a BUS SERVICE interrupt.
	 * If it isn't that, and it isn't a DISCONNECT
	 * interrupt, we have a "cannot happen" situation.
	 */
	if ((intr & FAS_INT_BUS) == 0) {
		if ((intr & FAS_INT_DISCON) == 0) {
			fas_printstate(fas, "cmd transmission error");
			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_CMD_DONE_ABORT1_END,
			    "fas_handle_cmd_done_end (abort1)");
			return (ACTION_ABORT_CURCMD);
		}
	} else {
		sp->cmd_pkt->pkt_state |= STATE_SENT_CMD;
	}

	fas->f_dma_csr = fas_dma_reg_read(fas, &dmar->dma_csr);
	FAS_FLUSH_DMA(fas);

	New_state(fas, ACTS_UNKNOWN);
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_CMD_DONE_END,
	    "fas_handle_cmd_done_end");
	return (fas_handle_unknown(fas));
}

/*
 * Begin to send a message out
 */
static int
fas_handle_msg_out_start(struct fas *fas)
{
	struct fas_cmd *sp = fas->f_current_sp;
	uchar_t *msgout = fas->f_cur_msgout;
	uchar_t amt = fas->f_omsglen;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_MSG_OUT_START,
	    "fas_handle_msg_out_start");
	EPRINTF("fas_handle_msg_out_start\n");

	/*
	 * Check to make *sure* that we are really
	 * in MESSAGE OUT phase. If the last state
	 * was ACTS_MSG_OUT_DONE, then we are trying
	 * to resend a message that the target stated
	 * had a parity error in it.
	 *
	 * If this is the case, and mark completion reason as CMD_NOMSGOUT.
	 * XXX: Right now, we just *drive* on. Should we abort the command?
	 */
	if ((fas->f_stat & FAS_PHASE_MASK) != FAS_PHASE_MSG_OUT &&
	    fas->f_laststate == ACTS_MSG_OUT_DONE) {
		fas_log(fas, CE_WARN,
		    "Target %d refused message resend", Tgt(sp));
		fas_set_pkt_reason(fas, sp, CMD_NOMSGOUT, 0);
		New_state(fas, ACTS_UNKNOWN);
		TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_MSG_OUT_PHASEMANAGE_END,
		    "fas_handle_msg_out_end (ACTION_PHASEMANAGE)");
		return (ACTION_PHASEMANAGE);
	}

	/*
	 * Clean the fifo.
	 */
	fas_reg_cmd_write(fas, CMD_FLUSH);

	if (amt == 0) {
		/*
		 * no msg to send
		 */
		*msgout = MSG_NOP;
		amt = fas->f_omsglen = 1;
	}

	/*
	 * If msg only 1 byte, just dump it in the fifo and go.  For
	 * multi-byte msgs, dma them to save time.  If we have no
	 * msg to send and we're in msg out phase, send a NOP.
	 */
	fas->f_last_msgout = *msgout;

	/*
	 * There is a bug in the fas366 that occasionaly
	 * deasserts the ATN signal prematurely when we send
	 * the sync/wide negotiation bytes out using DMA. The
	 * workaround here is to send the negotiation bytes out
	 * using PIO
	 */
	fas_write_fifo(fas, msgout, fas->f_omsglen, 1);
	fas_reg_cmd_write(fas, CMD_TRAN_INFO);

	EPRINTF2("amt=%x, last_msgout=%x\n", amt, fas->f_last_msgout);

	New_state(fas, ACTS_MSG_OUT_DONE);
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_MSG_OUT_END,
	    "fas_handle_msg_out_end");
	return (ACTION_RETURN);
}

static int
fas_handle_msg_out_done(struct fas *fas)
{
	struct fas_cmd *sp = fas->f_current_sp;
	uchar_t msgout, phase;
	int target = Tgt(sp);
	int	amt = fas->f_omsglen;
	int action;

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_MSG_OUT_DONE_START,
	    "fas_handle_msg_out_done_start");
	msgout = fas->f_cur_msgout[0];
	if ((msgout == MSG_HEAD_QTAG) || (msgout == MSG_SIMPLE_QTAG)) {
		msgout = fas->f_cur_msgout[2];
	}
	EPRINTF4("msgout: %x %x %x, last_msgout=%x\n",
	    fas->f_cur_msgout[0], fas->f_cur_msgout[1],
	    fas->f_cur_msgout[2], fas->f_last_msgout);

	EPRINTF1("fas_handle_msgout_done: msgout=%x\n", msgout);

	/*
	 * flush fifo, just in case some bytes were not sent
	 */
	fas_reg_cmd_write(fas, CMD_FLUSH);

	/*
	 * If the FAS disconnected, then the message we sent caused
	 * the target to decide to drop BSY* and clear the bus.
	 */
	if (fas->f_intr == FAS_INT_DISCON) {
		if (msgout == MSG_DEVICE_RESET || msgout == MSG_ABORT ||
		    msgout == MSG_ABORT_TAG) {
			/*
			 * If we sent a device reset msg, then we need to do
			 * a synch negotiate again unless we have already
			 * inhibited synch.
			 */
			if (msgout == MSG_ABORT || msgout == MSG_ABORT_TAG) {
				fas->f_abort_msg_sent++;
				if ((sp->cmd_flags & CFLAG_CMDPROXY) == 0) {
					fas_set_pkt_reason(fas, sp,
					    CMD_ABORTED, STAT_ABORTED);
				}
			} else if (msgout == MSG_DEVICE_RESET) {
				fas->f_reset_msg_sent++;
				if ((sp->cmd_flags & CFLAG_CMDPROXY) == 0) {
					fas_set_pkt_reason(fas, sp,
					    CMD_RESET, STAT_DEV_RESET);
				}
				fas_force_renegotiation(fas, Tgt(sp));
			}
			EPRINTF2("Successful %s message to target %d\n",
			    scsi_mname(msgout), target);

			if (sp->cmd_flags & CFLAG_CMDPROXY) {
				sp->cmd_cdb[FAS_PROXY_RESULT] = TRUE;
			}
			TRACE_0(TR_FAC_SCSI_FAS,
			    TR_FAS_HANDLE_MSG_OUT_DONE_FINISH_END,
			    "fas_handle_msg_out_done_end (ACTION_FINISH)");
			return (ACTION_FINISH);
		}
		/*
		 * If the target dropped busy on any other message, it
		 * wasn't expected. We will let the code in fas_phasemanage()
		 * handle this unexpected bus free event.
		 */
		goto out;
	}

	/*
	 * What phase have we transitioned to?
	 */
	phase = fas->f_stat & FAS_PHASE_MASK;

	/*
	 * If we finish sending a message out, and we are
	 * still in message out phase, then the target has
	 * detected one or more parity errors in the message
	 * we just sent and it is asking us to resend the
	 * previous message.
	 */
	if ((fas->f_intr & FAS_INT_BUS) && phase == FAS_PHASE_MSG_OUT) {
		/*
		 * As per SCSI-2 specification, if the message to
		 * be re-sent is greater than one byte, then we
		 * have to set ATN*.
		 */
		if (amt > 1) {
			fas_assert_atn(fas);
		}
		fas_log(fas, CE_WARN,
		    "SCSI bus MESSAGE OUT phase parity error");
		sp->cmd_pkt->pkt_statistics |= STAT_PERR;
		New_state(fas, ACTS_MSG_OUT);
		TRACE_0(TR_FAC_SCSI_FAS,
		    TR_FAS_HANDLE_MSG_OUT_DONE_PHASEMANAGE_END,
		    "fas_handle_msg_out_done_end (ACTION_PHASEMANAGE)");
		return (ACTION_PHASEMANAGE);
	}


out:
	fas->f_last_msgout = msgout;
	fas->f_omsglen = 0;
	New_state(fas, ACTS_UNKNOWN);
	action = fas_handle_unknown(fas);
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_HANDLE_MSG_OUT_DONE_END,
	    "fas_handle_msg_out_done_end");
	return (action);
}

static int
fas_twobyte_msg(struct fas *fas)
{
	struct fas_cmd *sp = fas->f_current_sp;

	if ((fas->f_imsgarea[0] == MSG_IGNORE_WIDE_RESID) &&
	    (fas->f_imsgarea[1] == 1)) {
		int xfer_amt;

		/*
		 * Knock off one byte if there
		 * is a last transfer and is even number of bytes
		 */
		xfer_amt = sp->cmd_data_count - sp->cmd_saved_data_count;
		if (xfer_amt && (!(xfer_amt & 1))) {
			ASSERT(sp->cmd_data_count > 0);
			sp->cmd_data_count--;
			sp->cmd_cur_addr--;
		}
		IPRINTF1("ignore wide resid %d\n", fas->f_imsgarea[1]);
		New_state(fas, ACTS_UNKNOWN);
		return (0);
	}

	fas_log(fas, CE_WARN,
	    "Two byte message '%s' 0x%x rejected",
	    scsi_mname(fas->f_imsgarea[0]), fas->f_imsgarea[1]);
	return (MSG_REJECT);
}

/*
 * handle receiving extended messages
 */
static int
fas_multibyte_msg(struct fas *fas)
{
#ifdef FASDEBUG
	static char *mbs =
	    "Target %d now Synchronous at %d.%d MB/s max transmit rate\n";
	static char *mbs1 =
	    "Target %d now Synchronous at %d.0%d MB/s max transmit rate\n";
	static char *mbs2 =
	    "Target %d now Synchronous at %d.00%d MB/s max transmit rate\n";
#endif
	struct fas_cmd *sp = fas->f_current_sp;
	volatile struct fasreg *fasreg = fas->f_reg;
	uchar_t emsg = fas->f_imsgarea[2];
	int tgt = Tgt(sp);
	int msgout = 0;

	EPRINTF("fas_multibyte_msg:\n");

	if (emsg == MSG_SYNCHRONOUS) {
		uint_t period, offset, regval;
		uint_t minsync, maxsync, clockval;
		uint_t xfer_freq, xfer_div, xfer_mod, xfer_rate;

		period = fas->f_imsgarea[3] & 0xff;
		offset = fas->f_imsgarea[4] & 0xff;
		minsync = MIN_SYNC_PERIOD(fas);
		maxsync = MAX_SYNC_PERIOD(fas);
		DPRINTF5("sync msg received: %x %x %x %x %x\n",
		    fas->f_imsgarea[0], fas->f_imsgarea[1],
		    fas->f_imsgarea[2], fas->f_imsgarea[3],
		    fas->f_imsgarea[4]);
		DPRINTF3("received period %d offset %d from tgt %d\n",
		    period, offset, tgt);
		DPRINTF3("calculated minsync %d, maxsync %d for tgt %d\n",
		    minsync, maxsync, tgt);
		DPRINTF2("sync period %d, neg period %d\n",
		    fas->f_sync_period[tgt], fas->f_neg_period[tgt]);

		if ((++(fas->f_sdtr_sent)) & 1) {
			/*
			 * In cases where the target negotiates synchronous
			 * mode before we do, and we either have sync mode
			 * disabled, or this target is known to be a weak
			 * signal target, we send back a message indicating
			 * a desire to stay in asynchronous mode (the SCSI-2
			 * spec states that if we have synchronous capability
			 * then we cannot reject a SYNCHRONOUS DATA TRANSFER
			 * REQUEST message).
			 */
			IPRINTF1("SYNC negotiation initiated by target %d\n",
			    tgt);

			msgout = MSG_EXTENDED;

			period =
			    period ? max(period, MIN_SYNC_PERIOD(fas)) : 0;

			if (fas->f_backoff & (1<<tgt)) {
				period = period ?
				    max(period, fas->f_neg_period[tgt]) : 0;
			}
			offset = min(offset, fas_default_offset);
		}
		xfer_freq = regval = 0;

		/*
		 * If the target's offset is bigger than ours,
		 * the target has violated the scsi protocol.
		 */
		if (offset > fas_default_offset) {
			period = offset = 0;
			msgout = MSG_REJECT;
		}

		if (offset && (period > maxsync)) {
			/*
			 * We cannot transmit data in synchronous
			 * mode this slow, so convert to asynchronous
			 * mode.
			 */
			msgout = MSG_EXTENDED;
			period = offset = 0;

		} else if (offset && (period < minsync)) {
			/*
			 * If the target's period is less than ours,
			 * the target has violated the scsi protocol.
			 */
			period = offset = 0;
			msgout = MSG_REJECT;

		} else if (offset) {
			/*
			 * Conversion method for received PERIOD value
			 * to the number of input clock ticks to the FAS.
			 *
			 * We adjust the input period value such that
			 * we always will transmit data *not* faster
			 * than the period value received.
			 */

			clockval = fas->f_clock_cycle / 1000;
			regval = (((period << 2) + clockval - 1) / clockval);

			/*
			 * correction if xfer rate <= 5MB/sec
			 * XXX do we need this?
			 */
			if (regval && (period >= FASTSCSI_THRESHOLD)) {
				regval--;
			}
		}

		fas->f_offset[tgt] = offset;
		fas->f_neg_period[tgt] = period;

		/*
		 * Is is now safe to produce a responce to a target
		 * initiated sdtr.  period and offset have been checked.
		 */
		if (msgout == MSG_EXTENDED) {
			fas_make_sdtr(fas, 0, tgt);
			period = fas->f_neg_period[tgt];
			offset = (fas->f_offset[tgt] & 0xf);
		}

		if (offset) {
			fas->f_sync_period[tgt] = regval & SYNC_PERIOD_MASK;
			fas_reg_write(fas, (uchar_t *)&fasreg->fas_sync_period,
			    fas->f_sync_period[tgt]);

			fas->f_offset[tgt] = offset | fas->f_req_ack_delay;
			fas_reg_write(fas, (uchar_t *)&fasreg->fas_sync_offset,
			    fas->f_offset[tgt]);

			/*
			 * if transferring > 5 MB/sec then enable
			 * fastscsi in conf3
			 */
			if (period < FASTSCSI_THRESHOLD) {
				fas->f_fasconf3[tgt] |= FAS_CONF3_FASTSCSI;
			} else {
				fas->f_fasconf3[tgt] &= ~FAS_CONF3_FASTSCSI;
			}

			fas_reg_write(fas, (uchar_t *)&fasreg->fas_conf3,
			    fas->f_fasconf3[tgt]);

			DPRINTF4("period %d (%d), offset %d to tgt %d\n",
			    period,
			    fas->f_sync_period[tgt] & SYNC_PERIOD_MASK,
			    fas->f_offset[tgt] & 0xf, tgt);
			DPRINTF1("req/ack delay = %x\n", fas->f_req_ack_delay);
			DPRINTF1("conf3 = %x\n", fas->f_fasconf3[tgt]);
#ifdef FASDEBUG
			/*
			 * Convert input clock cycle per
			 * byte to nanoseconds per byte.
			 * (ns/b), and convert that to
			 * k-bytes/second.
			 */
			xfer_freq = FAS_SYNC_KBPS((regval *
			    fas->f_clock_cycle) / 1000);
			xfer_rate = ((fas->f_nowide & (1<<tgt))? 1 : 2) *
			    xfer_freq;
			xfer_div = xfer_rate / 1000;
			xfer_mod = xfer_rate % 1000;


			if (xfer_mod > 99) {
				IPRINTF3(mbs, tgt, xfer_div, xfer_mod);
			} else if (xfer_mod > 9) {
				IPRINTF3(mbs1, tgt, xfer_div, xfer_mod);
			} else {
				IPRINTF3(mbs2, tgt, xfer_div, xfer_mod);
			}
#endif
			fas->f_sync_enabled |= (1<<tgt);

		} else {
			/*
			 * We are converting back to async mode.
			 */
			fas_revert_to_async(fas, tgt);
		}

		/*
		 * If this target violated the scsi spec, reject the
		 * sdtr msg and don't negotiate sdtr again.
		 */
		if (msgout == MSG_REJECT) {
			fas->f_nosync |= (1<<tgt);
		}

		fas->f_props_update |= (1<<tgt);

	} else	if (emsg == MSG_WIDE_DATA_XFER) {
		uchar_t width = fas->f_imsgarea[3] & 0xff;

		DPRINTF4("wide msg received: %x %x %x %x\n",
		    fas->f_imsgarea[0], fas->f_imsgarea[1],
		    fas->f_imsgarea[2], fas->f_imsgarea[3]);

		/* always renegotiate sync after wide */
		msgout = MSG_EXTENDED;

		if ((++(fas->f_wdtr_sent)) &	1) {
			IPRINTF1("Wide negotiation initiated by target %d\n",
			    tgt);
			/*
			 * allow wide neg even if the target driver hasn't
			 * enabled wide yet.
			 */
			fas->f_nowide &= ~(1<<tgt);
			fas_make_wdtr(fas, 0, tgt, width);
			IPRINTF1("sending wide sync %d back\n", width);
			/*
			 * Let us go back to async mode(SCSI spec)
			 * and depend on target to do sync
			 * after wide negotiations.
			 * If target does not do a sync neg and enters
			 * async mode we will negotiate sync on next command
			 */
			fas_revert_to_async(fas, tgt);
			fas->f_sync_known &= ~(1<<tgt);
		} else {
			/*
			 * renegotiate sync after wide
			 */
			fas_set_wide_conf3(fas, tgt, width);
			ASSERT(width <= 1);
			fas->f_wdtr_sent = 0;
			if ((fas->f_nosync & (1<<tgt)) == 0) {
				fas_make_sdtr(fas, 0, tgt);
			} else {
				msgout = 0;
			}
		}

		fas->f_props_update |= (1<<tgt);

	} else if (emsg == MSG_MODIFY_DATA_PTR) {
		msgout = MSG_REJECT;
	} else {
		fas_log(fas, CE_WARN,
		    "Rejecting message %s 0x%x from Target %d",
		    scsi_mname(MSG_EXTENDED), emsg, tgt);
		msgout = MSG_REJECT;
	}
out:
	New_state(fas, ACTS_UNKNOWN);
	return (msgout);
}

/*
 * Back off sync negotiation
 * and got to async mode
 */
static void
fas_revert_to_async(struct fas *fas, int tgt)
{
	volatile struct fasreg *fasreg = fas->f_reg;

	fas->f_sync_period[tgt] = 0;
	fas_reg_write(fas, (uchar_t *)&fasreg->fas_sync_period, 0);
	fas->f_offset[tgt] = 0;
	fas_reg_write(fas, (uchar_t *)&fasreg->fas_sync_offset, 0);
	fas->f_fasconf3[tgt] &= ~FAS_CONF3_FASTSCSI;
	fas_reg_write(fas, &fasreg->fas_conf3, fas->f_fasconf3[tgt]);
	fas->f_sync_enabled &= ~(1<<tgt);
}

/*
 * handle an unexpected selection attempt
 * XXX look for better way: msg reject, drop off the bus
 */
static int
fas_handle_selection(struct fas *fas)
{
	fas_reg_cmd_write(fas, CMD_DISCONNECT);
	fas_reg_cmd_write(fas, CMD_FLUSH);
	fas_reg_cmd_write(fas, CMD_EN_RESEL);
	return (ACTION_RETURN);
}

/*
 * dma window handling
 */
static int
fas_restore_pointers(struct fas *fas, struct fas_cmd *sp)
{
	if (sp->cmd_data_count != sp->cmd_saved_data_count) {
		sp->cmd_data_count = sp->cmd_saved_data_count;
		sp->cmd_cur_addr = sp->cmd_saved_cur_addr;

		if (sp->cmd_cur_win != sp->cmd_saved_win) {
			sp->cmd_cur_win = sp->cmd_saved_win;
			if (fas_set_new_window(fas, sp)) {
				return (-1);
			}
		}
		DPRINTF1("curaddr=%x\n", sp->cmd_cur_addr);
	}
	return (0);
}

static int
fas_set_new_window(struct fas *fas, struct fas_cmd *sp)
{
	off_t offset;
	size_t len;
	uint_t count;

	if (ddi_dma_getwin(sp->cmd_dmahandle, sp->cmd_cur_win,
	    &offset, &len, &sp->cmd_dmacookie, &count) != DDI_SUCCESS) {
		return (-1);
	}

	DPRINTF4("new window %x: off=%lx, len=%lx, count=%x\n",
	    sp->cmd_cur_win, offset, len, count);

	ASSERT(count == 1);
	return (0);
}

static int
fas_next_window(struct fas *fas, struct fas_cmd *sp, uint64_t end)
{

	/* are there more windows? */
	if (sp->cmd_nwin == 0) {
		uint_t nwin = 0;
		(void) ddi_dma_numwin(sp->cmd_dmahandle, &nwin);
		sp->cmd_nwin = (uchar_t)nwin;
	}

	DPRINTF5(
	    "cmd_data_count=%x, dmacount=%x, curaddr=%x, end=%lx, nwin=%x\n",
	    sp->cmd_data_count, sp->cmd_dmacount, sp->cmd_cur_addr, end,
	    sp->cmd_nwin);

	if (sp->cmd_cur_win < sp->cmd_nwin) {
		sp->cmd_cur_win++;
		if (fas_set_new_window(fas, sp)) {
			fas_printstate(fas, "cannot set new window");
			sp->cmd_cur_win--;
			return (-1);
		}
	/*
	 * if there are no more windows, we have a data overrun condition
	 */
	} else {
		int slot = sp->cmd_slot;

		fas_printstate(fas, "data transfer overrun");
		fas_set_pkt_reason(fas, sp, CMD_DATA_OVR, 0);

		/*
		 * if we get data transfer overruns, assume we have
		 * a weak scsi bus. Note that this won't catch consistent
		 * underruns or other noise related syndromes.
		 */
		fas_sync_wide_backoff(fas, sp, slot);
		return (-1);
	}
	sp->cmd_cur_addr = sp->cmd_dmacookie.dmac_address;
	DPRINTF1("cur_addr=%x\n", sp->cmd_cur_addr);
	return (0);
}

/*
 * dma error handler
 */
static int
fas_check_dma_error(struct fas *fas)
{
	/*
	 * was there a dma error that	caused fas_intr_svc() to be called?
	 */
	if (fas->f_dma->dma_csr & DMA_ERRPEND) {
		/*
		 * It would be desirable to set the ATN* line and attempt to
		 * do the whole schmear of INITIATOR DETECTED ERROR here,
		 * but that is too hard to do at present.
		 */
		fas_log(fas, CE_WARN, "Unrecoverable DMA error");
		fas_printstate(fas, "dma error");
		fas_set_pkt_reason(fas, fas->f_current_sp, CMD_TRAN_ERR, 0);
		return (-1);
	}
	return (0);
}

/*
 * check for gross error or spurious interrupt
 */
static int
fas_handle_gross_err(struct fas *fas)
{
	volatile struct fasreg *fasreg = fas->f_reg;

	fas_log(fas, CE_WARN,
	"gross error in fas status (%x)", fas->f_stat);

	IPRINTF5("fas_cmd=%x, stat=%x, intr=%x, step=%x, fifoflag=%x\n",
	    fasreg->fas_cmd, fas->f_stat, fas->f_intr, fasreg->fas_step,
	    fasreg->fas_fifo_flag);

	fas_set_pkt_reason(fas, fas->f_current_sp, CMD_TRAN_ERR, 0);

	fas_internal_reset(fas, FAS_RESET_FAS);
	return (ACTION_RESET);
}


/*
 * handle illegal cmd interrupt or (external) bus reset cleanup
 */
static int
fas_illegal_cmd_or_bus_reset(struct fas *fas)
{
	/*
	 * If we detect a SCSI reset, we blow away the current
	 * command (if there is one) and all disconnected commands
	 * because we now don't know the state of them at all.
	 */
	ASSERT(fas->f_intr & (FAS_INT_ILLEGAL | FAS_INT_RESET));

	if (fas->f_intr & FAS_INT_RESET) {
		return (ACTION_FINRST);
	}

	/*
	 * Illegal cmd to fas:
	 * This should not happen. The one situation where
	 * we can get an ILLEGAL COMMAND interrupt is due to
	 * a bug in the FAS366 during reselection which we
	 * should be handling in fas_reconnect().
	 */
	if (fas->f_intr & FAS_INT_ILLEGAL) {
		IPRINTF1("lastcmd=%x\n", fas->f_reg->fas_cmd);
		fas_printstate(fas, "ILLEGAL bit set");
		return (ACTION_RESET);
	}
	/*NOTREACHED*/
	return (ACTION_RETURN);
}

/*
 * set throttles for all luns of this target
 */
static void
fas_set_throttles(struct fas *fas, int slot, int n, int what)
{
	int i;

	/*
	 * if the bus is draining/quiesced, no changes to the throttles
	 * are allowed. Not allowing change of throttles during draining
	 * limits error recovery but will reduce draining time
	 *
	 * all throttles should have been set to HOLD_THROTTLE
	 */
	if (fas->f_softstate & (FAS_SS_QUIESCED | FAS_SS_DRAINING)) {
		return;
	}

	ASSERT((n == 1) || (n == N_SLOTS) || (n == NLUNS_PER_TARGET));
	ASSERT((slot + n) <= N_SLOTS);
	if (n == NLUNS_PER_TARGET) {
		slot &= ~(NLUNS_PER_TARGET - 1);
	}

	for (i = slot; i < (slot + n); i++) {
		if (what == HOLD_THROTTLE) {
			fas->f_throttle[i] = HOLD_THROTTLE;
		} else if ((fas->f_reset_delay[i/NLUNS_PER_TARGET]) == 0) {
			if (what == MAX_THROTTLE) {
				int tshift = 1 << (i/NLUNS_PER_TARGET);
				fas->f_throttle[i] = (short)
				    ((fas->f_notag & tshift)? 1 : what);
			} else {
				fas->f_throttle[i] = what;
			}
		}
	}
}

static void
fas_set_all_lun_throttles(struct fas *fas, int slot, int what)
{
	/*
	 * fas_set_throttle will adjust slot to starting at LUN 0
	 */
	fas_set_throttles(fas, slot, NLUNS_PER_TARGET, what);
}

static void
fas_full_throttle(struct fas *fas, int slot)
{
	fas_set_throttles(fas, slot, 1, MAX_THROTTLE);
}

/*
 * run a polled cmd
 */
static void
fas_runpoll(struct fas *fas, short slot, struct fas_cmd *sp)
{
	int limit, i, n;
	int timeout = 0;

	DPRINTF4("runpoll: slot=%x, cmd=%x, current_sp=0x%p, tcmds=%x\n",
	    slot, *((uchar_t *)sp->cmd_pkt->pkt_cdbp),
	    (void *)fas->f_current_sp, fas->f_tcmds[slot]);

	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_RUNPOLL_START, "fas_runpoll_start");

	/*
	 * wait for cmd to complete
	 * don't start new cmds so set throttles to HOLD_THROTTLE
	 */
	while ((sp->cmd_flags & CFLAG_COMPLETED) == 0) {
		if (!(sp->cmd_flags & CFLAG_CMDPROXY)) {
			fas_set_all_lun_throttles(fas, slot, HOLD_THROTTLE);
		}
		if ((fas->f_state != STATE_FREE) || INTPENDING(fas)) {
			if (fas_dopoll(fas, POLL_TIMEOUT) <= 0) {
				IPRINTF("runpoll: timeout on draining\n");
				goto bad;
			}
		}

		ASSERT(fas->f_state == STATE_FREE);
		ASSERT(fas->f_current_sp == NULL);

		/*
		 * if this is not a proxy cmd, don't start the cmd
		 * without draining the active cmd(s)
		 * for proxy cmds, we zap the active cmd and assume
		 * that the caller will take care of this
		 * For tagged cmds, wait with submitting a non-tagged
		 * cmd until the queue has been drained
		 * If the cmd is a request sense, then draining won't
		 * help since we are in contingence allegiance condition
		 */
		if (!(sp->cmd_flags & CFLAG_CMDPROXY)) {
			uchar_t *cmdp = (uchar_t *)sp->cmd_pkt->pkt_cdbp;

			if ((fas->f_tcmds[slot]) &&
			    (NOTAG(Tgt(sp)) ||
			    (((sp->cmd_pkt_flags & FLAG_TAGMASK) == 0) &&
			    (*cmdp != SCMD_REQUEST_SENSE)))) {
				if (timeout < POLL_TIMEOUT) {
					timeout += 100;
					drv_usecwait(100);
					continue;
				} else {
					fas_log(fas, CE_WARN,
					    "polled cmd failed (target busy)");
					goto cleanup;
				}
			}
		}

		/*
		 * If the draining of active commands killed the
		 * the current polled command, we're done..
		 */
		if (sp->cmd_flags & CFLAG_COMPLETED) {
			break;
		}

		/*
		 * ensure we are not accessing a target too quickly
		 * after a reset. the throttles get set back later
		 * by the reset delay watch; hopefully, we don't go
		 * thru this loop more than once
		 */
		if (fas->f_reset_delay[slot/NLUNS_PER_TARGET]) {
			IPRINTF1("reset delay set for slot %x\n", slot);
			drv_usecwait(fas->f_scsi_reset_delay * 1000);
			for (i = 0; i < NTARGETS_WIDE; i++) {
				if (fas->f_reset_delay[i]) {
					int s = i * NLUNS_PER_TARGET;
					int e = s + NLUNS_PER_TARGET;
					fas->f_reset_delay[i] = 0;
					for (; s < e; s++) {
						fas_full_throttle(fas, s);
					}
				}
			}
		}

		/*
		 * fas_startcmd() will return false if preempted
		 * or draining
		 */
		if (fas_startcmd(fas, sp) != TRUE) {
			IPRINTF("runpoll: cannot start new cmds\n");
			ASSERT(fas->f_current_sp != sp);
			continue;
		}

		/*
		 * We're now 'running' this command.
		 *
		 * fas_dopoll will always return when
		 * fas->f_state is STATE_FREE, and
		 */
		limit = sp->cmd_pkt->pkt_time * 1000000;
		if (limit == 0) {
			limit = POLL_TIMEOUT;
		}

		/*
		 * if the cmd disconnected, the first call to fas_dopoll
		 * will return with bus free; we go thru the loop one more
		 * time and wait limit usec for the target to reconnect
		 */
		for (i = 0; i <= POLL_TIMEOUT; i += 100) {

			if ((n = fas_dopoll(fas, limit)) <= 0) {
				IPRINTF("runpoll: timeout on polling\n");
				goto bad;
			}

			/*
			 * If a preemption occurred that caused this
			 * command to actually not start, go around
			 * the loop again. If CFLAG_COMPLETED is set, the
			 * command completed
			 */
			if ((sp->cmd_flags & CFLAG_COMPLETED) ||
			    (sp->cmd_pkt->pkt_state == 0)) {
				break;
			}

			/*
			 * the bus may have gone free because the target
			 * disconnected; go thru the loop again
			 */
			ASSERT(fas->f_state == STATE_FREE);
			if (n == 0) {
				/*
				 * bump i, we have waited limit usecs in
				 * fas_dopoll
				 */
				i += limit - 100;
			}
		}

		if ((sp->cmd_flags & CFLAG_COMPLETED) == 0) {

			if (i > POLL_TIMEOUT) {
				IPRINTF("polled timeout on disc. cmd\n");
				goto bad;
			}

			if (sp->cmd_pkt->pkt_state) {
				/*
				 * don't go thru the loop again; the cmd
				 * was already started
				 */
				IPRINTF("fas_runpoll: cmd started??\n");
				goto bad;
			}
		}
	}

	/*
	 * blindly restore throttles which is preferable over
	 * leaving throttle hanging at 0 and noone to clear it
	 */
	if (!(sp->cmd_flags & CFLAG_CMDPROXY)) {
		fas_set_all_lun_throttles(fas, slot, MAX_THROTTLE);
	}

	/*
	 * ensure that the cmd is completely removed
	 */
	fas_remove_cmd(fas, sp, 0);

	/*
	 * If we stored up commands to do, start them off now.
	 */
	if ((fas->f_state == STATE_FREE) &&
	    (!(sp->cmd_flags & CFLAG_CMDPROXY))) {
		(void) fas_ustart(fas);
	}
exit:
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_RUNPOLL_END, "fas_runpoll_end");
	return;

bad:
	fas_log(fas, CE_WARN, "Polled cmd failed");
#ifdef FASDEBUG
	fas_printstate(fas, "fas_runpoll: polled cmd failed");
#endif /* FASDEBUG */

cleanup:
	fas_set_all_lun_throttles(fas, slot, MAX_THROTTLE);

	/*
	 * clean up all traces of this sp because fas_runpoll will return
	 * before fas_reset_recovery() cleans up
	 */
	fas_remove_cmd(fas, sp, NEW_TIMEOUT);
	fas_decrement_ncmds(fas, sp);
	fas_set_pkt_reason(fas, sp, CMD_TRAN_ERR, 0);

	if ((sp->cmd_flags & CFLAG_CMDPROXY) == 0) {
		(void) fas_reset_bus(fas);
	}
	goto exit;
}

/*
 * Poll for command completion (i.e., no interrupts)
 * limit is in usec (and will not be very accurate)
 *
 * the assumption is that we only run polled cmds in interrupt context
 * as scsi_transport will filter out FLAG_NOINTR
 */
static int
fas_dopoll(struct fas *fas, int limit)
{
	int i, n;

	/*
	 * timeout is not very accurate since we don't know how
	 * long the poll takes
	 * also if the packet gets started fairly late, we may
	 * timeout prematurely
	 * fas_dopoll always returns if e_state transitions to STATE_FREE
	 */
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_DOPOLL_START, "fas_dopoll_start");

	if (limit == 0) {
		limit = POLL_TIMEOUT;
	}

	for (n = i = 0; i < limit; i += 100) {
		if (INTPENDING(fas)) {
			fas->f_polled_intr = 1;
			n++;
			(void) fas_intr_svc(fas);
			if (fas->f_state == STATE_FREE)
				break;
		}
		drv_usecwait(100);
	}

	if (i >= limit && fas->f_state != STATE_FREE) {
		fas_printstate(fas, "polled command timeout");
		n = -1;
	}
	TRACE_1(TR_FAC_SCSI_FAS, TR_FAS_DOPOLL_END,
	    "fas_dopoll_end: rval %x", n);
	return (n);
}

/*
 * prepare a sync negotiation message
 */
static void
fas_make_sdtr(struct fas *fas, int msgout_offset, int target)
{
	uchar_t *p = fas->f_cur_msgout + msgout_offset;
	ushort_t tshift = 1<<target;
	uchar_t period = MIN_SYNC_PERIOD(fas);
	uchar_t offset = fas_default_offset;

	/*
	 * If this target experienced a sync backoff use the
	 * target's sync speed that was adjusted in
	 * fas_sync_wide_backoff.  For second sync backoff,
	 * offset will be ajusted below in sanity checks.
	 */
	if (fas->f_backoff & tshift) {
		period = fas->f_neg_period[target];
	}

	/*
	 * If this is a responce to a target initiated sdtr,
	 * use the agreed upon values.
	 */
	if (fas->f_sdtr_sent & 1) {
		period = fas->f_neg_period[target];
		offset = fas->f_offset[target];
	}

	/*
	 * If the target driver disabled
	 * sync then make offset = 0
	 */
	if (fas->f_force_async & tshift) {
		offset = 0;
	}

	/*
	 * sanity check of period and offset
	 */
	if (fas->f_target_scsi_options[target] & SCSI_OPTIONS_FAST) {
		if (period < (uchar_t)(DEFAULT_FASTSYNC_PERIOD/4)) {
			period = (uchar_t)(DEFAULT_FASTSYNC_PERIOD/4);
		}
	} else if (fas->f_target_scsi_options[target] & SCSI_OPTIONS_SYNC) {
		if (period < (uchar_t)(DEFAULT_SYNC_PERIOD/4)) {
			period = (uchar_t)(DEFAULT_SYNC_PERIOD/4);
		}
	} else {
		fas->f_nosync |= tshift;
	}

	if (fas->f_nosync & tshift) {
		offset = 0;
	}

	if ((uchar_t)(offset & 0xf) > fas_default_offset) {
		offset = fas_default_offset | fas->f_req_ack_delay;
	}

	fas->f_neg_period[target] = (uchar_t)period;
	fas->f_offset[target] = (uchar_t)offset;

	*p++ = (uchar_t)MSG_EXTENDED;
	*p++ = (uchar_t)3;
	*p++ = (uchar_t)MSG_SYNCHRONOUS;
	*p++ = period;
	*p++ = offset & 0xf;
	fas->f_omsglen = 5 + msgout_offset;

	IPRINTF2("fas_make_sdtr: period = %x, offset = %x\n",
	    period, offset);
	/*
	 * increment sdtr flag, odd value indicates that we initiated
	 * the negotiation
	 */
	fas->f_sdtr_sent++;

	/*
	 * the target may reject the optional sync message so
	 * to avoid negotiating on every cmd, set sync known here
	 * we should not negotiate wide after sync again
	 */
	fas->f_sync_known |= 1<<target;
	fas->f_wide_known |= 1<<target;
}

/*
 * prepare a wide negotiation message
 */
static void
fas_make_wdtr(struct fas *fas, int msgout_offset, int target, int width)
{
	uchar_t *p = fas->f_cur_msgout + msgout_offset;

	if (((fas->f_target_scsi_options[target] & SCSI_OPTIONS_WIDE) == 0) ||
	    (fas->f_nowide & (1<<target))) {
		fas->f_nowide |= 1<<target;
		width = 0;
	}
	if (fas->f_force_narrow & (1<<target)) {
		width = 0;
	}
	width = min(FAS_XFER_WIDTH, width);

	*p++ = (uchar_t)MSG_EXTENDED;
	*p++ = (uchar_t)2;
	*p++ = (uchar_t)MSG_WIDE_DATA_XFER;
	*p++ = (uchar_t)width;
	fas->f_omsglen = 4 + msgout_offset;
	IPRINTF1("fas_make_wdtr: width=%x\n", width);

	/*
	 * increment wdtr flag, odd value indicates that we initiated
	 * the negotiation
	 */
	fas->f_wdtr_sent++;

	/*
	 * the target may reject the optional wide message so
	 * to avoid negotiating on every cmd, set wide known here
	 */
	fas->f_wide_known |= 1<<target;

	fas_set_wide_conf3(fas, target, width);
}

/*
 * auto request sense support
 * create or destroy an auto request sense packet
 */
static int
fas_create_arq_pkt(struct fas *fas, struct scsi_address *ap)
{
	/*
	 * Allocate a request sense packet using get_pktiopb
	 */
	struct fas_cmd *rqpktp;
	uchar_t slot = ap->a_target * NLUNS_PER_TARGET | ap->a_lun;
	struct buf *bp;
	struct arq_private_data *arq_data;

	/*
	 * if one exists, don't create another
	 */
	if (fas->f_arq_pkt[slot] != 0) {
		return (0);
	}

	/*
	 * it would be nicer if we could allow the target driver
	 * to specify the size but this is easier and OK for most
	 * drivers to use SENSE_LENGTH
	 * Allocate a request sense packet.
	 */
	bp = scsi_alloc_consistent_buf(ap, (struct buf *)NULL,
	    SENSE_LENGTH, B_READ, SLEEP_FUNC, NULL);
	rqpktp = PKT2CMD(scsi_init_pkt(ap,
	    NULL, bp, CDB_GROUP0, 1, PKT_PRIV_LEN,
	    PKT_CONSISTENT, SLEEP_FUNC, NULL));
	arq_data =
	    (struct arq_private_data *)(rqpktp->cmd_pkt->pkt_private);
	arq_data->arq_save_bp = bp;

	RQ_MAKECOM_G0((CMD2PKT(rqpktp)),
	    FLAG_SENSING | FLAG_HEAD | FLAG_NODISCON,
	    (char)SCMD_REQUEST_SENSE, 0, (char)SENSE_LENGTH);
	rqpktp->cmd_flags |= CFLAG_CMDARQ;
	rqpktp->cmd_slot = slot;
	rqpktp->cmd_pkt->pkt_ha_private = rqpktp;
	fas->f_arq_pkt[slot] = rqpktp;

	/*
	 * we need a function ptr here so abort/reset can
	 * defer callbacks; fas_call_pkt_comp() calls
	 * fas_complete_arq_pkt() directly without releasing the lock
	 * However, since we are not calling back directly thru
	 * pkt_comp, don't check this with warlock
	 */
#ifndef __lock_lint
	rqpktp->cmd_pkt->pkt_comp =
	    (void (*)(struct scsi_pkt *))fas_complete_arq_pkt;
#endif
	return (0);
}

static int
fas_delete_arq_pkt(struct fas *fas, struct scsi_address *ap)
{
	struct fas_cmd *rqpktp;
	int slot = ap->a_target * NLUNS_PER_TARGET | ap->a_lun;

	/*
	 * if there is still a pkt saved or no rqpkt
	 * then we cannot deallocate or there is nothing to do
	 */
	if ((rqpktp = fas->f_arq_pkt[slot]) != NULL) {
		struct arq_private_data *arq_data =
		    (struct arq_private_data *)(rqpktp->cmd_pkt->pkt_private);
		struct buf *bp = arq_data->arq_save_bp;
		/*
		 * is arq pkt in use?
		 */
		if (arq_data->arq_save_sp) {
			return (-1);
		}

		scsi_destroy_pkt(CMD2PKT(rqpktp));
		scsi_free_consistent_buf(bp);
		fas->f_arq_pkt[slot] = 0;
	}
	return (0);
}

/*
 * complete an arq packet by copying over transport info and the actual
 * request sense data; called with mutex held from fas_call_pkt_comp()
 */
void
fas_complete_arq_pkt(struct scsi_pkt *pkt)
{
	struct fas *fas = ADDR2FAS(&pkt->pkt_address);
	struct fas_cmd *sp = pkt->pkt_ha_private;
	struct scsi_arq_status *arqstat;
	struct arq_private_data *arq_data =
	    (struct arq_private_data *)sp->cmd_pkt->pkt_private;
	struct fas_cmd *ssp = arq_data->arq_save_sp;
	struct buf *bp = arq_data->arq_save_bp;
	int	slot = sp->cmd_slot;

	DPRINTF1("completing arq pkt sp=0x%p\n", (void *)sp);
	ASSERT(sp == fas->f_arq_pkt[slot]);
	ASSERT(arq_data->arq_save_sp != NULL);
	ASSERT(ssp != fas->f_active[sp->cmd_slot]->f_slot[sp->cmd_tag[1]]);

	arqstat = (struct scsi_arq_status *)(ssp->cmd_pkt->pkt_scbp);
	arqstat->sts_rqpkt_status = *((struct scsi_status *)
	    (sp->cmd_pkt->pkt_scbp));
	arqstat->sts_rqpkt_reason = sp->cmd_pkt->pkt_reason;
	arqstat->sts_rqpkt_state  = sp->cmd_pkt->pkt_state;
	arqstat->sts_rqpkt_statistics = sp->cmd_pkt->pkt_statistics;
	arqstat->sts_rqpkt_resid  = sp->cmd_pkt->pkt_resid;
	arqstat->sts_sensedata =
	    *((struct scsi_extended_sense *)bp->b_un.b_addr);
	ssp->cmd_pkt->pkt_state |= STATE_ARQ_DONE;
	arq_data->arq_save_sp = NULL;

	/*
	 * ASC=0x47 is parity error
	 */
	if (arqstat->sts_sensedata.es_key == KEY_ABORTED_COMMAND &&
	    arqstat->sts_sensedata.es_add_code == 0x47) {
		fas_sync_wide_backoff(fas, sp, slot);
	}

	fas_call_pkt_comp(fas, ssp);
}

/*
 * handle check condition and start an arq packet
 */
static int
fas_handle_sts_chk(struct fas *fas, struct fas_cmd *sp)
{
	struct fas_cmd *arqsp =	fas->f_arq_pkt[sp->cmd_slot];
	struct arq_private_data *arq_data;
	struct buf *bp;

	if ((arqsp == NULL) || (arqsp == sp) ||
	    (sp->cmd_scblen < sizeof (struct scsi_arq_status))) {
		IPRINTF("no arq packet or cannot arq on arq pkt\n");
		fas_call_pkt_comp(fas, sp);
		return (0);
	}

	arq_data = (struct arq_private_data *)arqsp->cmd_pkt->pkt_private;
	bp = arq_data->arq_save_bp;

	ASSERT(sp->cmd_flags & CFLAG_FINISHED);
	ASSERT(sp != fas->f_active[sp->cmd_slot]->f_slot[sp->cmd_tag[1]]);
	DPRINTF3("start arq for slot=%x, arqsp=0x%p, rqpkt=0x%p\n",
	    sp->cmd_slot, (void *)arqsp, (void *)fas->f_arq_pkt[sp->cmd_slot]);
	if (arq_data->arq_save_sp != NULL) {
		IPRINTF("auto request sense already in progress\n");
		goto fail;
	}

	arq_data->arq_save_sp = sp;

	bzero(bp->b_un.b_addr, sizeof (struct scsi_extended_sense));

	/*
	 * copy the timeout from the original packet by lack of a better
	 * value
	 * we could take the residue of the timeout but that could cause
	 * premature timeouts perhaps
	 */
	arqsp->cmd_pkt->pkt_time = sp->cmd_pkt->pkt_time;
	arqsp->cmd_flags &= ~CFLAG_TRANFLAG;
	ASSERT(arqsp->cmd_pkt->pkt_comp != NULL);

	/*
	 * make sure that auto request sense always goes out
	 * after queue full and after throttle was set to draining
	 */
	fas_full_throttle(fas, sp->cmd_slot);
	(void) fas_accept_pkt(fas, arqsp, NO_TRAN_BUSY);
	return (0);

fail:
	fas_set_pkt_reason(fas, sp, CMD_TRAN_ERR, 0);
	fas_log(fas, CE_WARN, "auto request sense failed\n");
	fas_dump_cmd(fas, sp);
	fas_call_pkt_comp(fas, sp);
	return (-1);
}


/*
 * handle qfull condition
 */
static void
fas_handle_qfull(struct fas *fas, struct fas_cmd *sp)
{
	int slot = sp->cmd_slot;

	if ((++sp->cmd_qfull_retries > fas->f_qfull_retries[Tgt(sp)]) ||
	    (fas->f_qfull_retries[Tgt(sp)] == 0)) {
		/*
		 * We have exhausted the retries on QFULL, or,
		 * the target driver has indicated that it
		 * wants to handle QFULL itself by setting
		 * qfull-retries capability to 0. In either case
		 * we want the target driver's QFULL handling
		 * to kick in. We do this by having pkt_reason
		 * as CMD_CMPLT and pkt_scbp as STATUS_QFULL.
		 */
		IPRINTF2("%d.%d: status queue full, retries over\n",
		    Tgt(sp), Lun(sp));
		fas_set_all_lun_throttles(fas, slot, DRAIN_THROTTLE);
		fas_call_pkt_comp(fas, sp);
	} else {
		if (fas->f_reset_delay[Tgt(sp)] == 0) {
			fas->f_throttle[slot] =
			    max((fas->f_tcmds[slot] - 2), 0);
		}
		IPRINTF3("%d.%d: status queue full, new throttle = %d, "
		    "retrying\n", Tgt(sp), Lun(sp), fas->f_throttle[slot]);
		sp->cmd_pkt->pkt_flags |= FLAG_HEAD;
		sp->cmd_flags &= ~CFLAG_TRANFLAG;
		(void) fas_accept_pkt(fas, sp, NO_TRAN_BUSY);

		/*
		 * when target gives queue full status with no commands
		 * outstanding (f_tcmds[] == 0), throttle is set to 0
		 * (HOLD_THROTTLE), and the queue full handling starts
		 * (see psarc/1994/313); if there are commands outstanding,
		 * the throttle is set to (f_tcmds[] - 2)
		 */
		if (fas->f_throttle[slot] == HOLD_THROTTLE) {
			/*
			 * By setting throttle to QFULL_THROTTLE, we
			 * avoid submitting new commands and in
			 * fas_restart_cmd find out slots which need
			 * their throttles to be cleared.
			 */
			fas_set_all_lun_throttles(fas, slot, QFULL_THROTTLE);
			if (fas->f_restart_cmd_timeid == 0) {
				fas->f_restart_cmd_timeid =
				    timeout(fas_restart_cmd, fas,
				    fas->f_qfull_retry_interval[Tgt(sp)]);
			}
		}
	}
}

/*
 * invoked from timeout() to restart qfull cmds with throttle == 0
 */
static void
fas_restart_cmd(void *fas_arg)
{
	struct fas *fas = fas_arg;
	int i;

	IPRINTF("fas_restart_cmd:\n");

	mutex_enter(FAS_MUTEX(fas));
	fas->f_restart_cmd_timeid = 0;

	for (i = 0; i < N_SLOTS; i += NLUNS_PER_TARGET) {
		if (fas->f_reset_delay[i/NLUNS_PER_TARGET] == 0) {
			if (fas->f_throttle[i] == QFULL_THROTTLE) {
				fas_set_all_lun_throttles(fas,
				    i, MAX_THROTTLE);
			}
		}
	}

	(void) fas_ustart(fas);
	mutex_exit(FAS_MUTEX(fas));
}

/*
 * Timeout handling:
 * Command watchdog routines
 */

/*ARGSUSED*/
static void
fas_watch(void *arg)
{
	struct fas *fas;
	ushort_t	props_update = 0;

	rw_enter(&fas_global_rwlock, RW_READER);

	for (fas = fas_head; fas != (struct fas *)NULL; fas = fas->f_next) {

		mutex_enter(FAS_MUTEX(fas));
		IPRINTF2("ncmds=%x, ndisc=%x\n", fas->f_ncmds, fas->f_ndisc);

#ifdef FAS_PIO_COUNTS
	if (fas->f_total_cmds) {
		int n = fas->f_total_cmds;

		fas_log(fas, CE_NOTE,
	"total=%d, cmds=%d fas-rd=%d, fas-wrt=%d, dma-rd=%d, dma-wrt=%d\n",
		    fas->f_total_cmds,
		    fas->f_reg_cmds/n,
		    fas->f_reg_reads/n, fas->f_reg_writes/n,
		    fas->f_reg_dma_reads/n, fas->f_reg_dma_writes/n);

		fas->f_reg_reads = fas->f_reg_writes =
		    fas->f_reg_dma_reads = fas->f_reg_dma_writes =
		    fas->f_reg_cmds = fas->f_total_cmds = 0;
	}
#endif
		if (fas->f_ncmds) {
			int i;
			fas_watchsubr(fas);

			/*
			 * reset throttle. the throttle may have been
			 * too low if queue full was caused by
			 * another initiator
			 * Only reset throttle if no cmd active in slot 0
			 * (untagged cmd)
			 */
#ifdef FAS_TEST
			if (fas_enable_untagged) {
				fas_test_untagged++;
			}
#endif
			for (i = 0; i < N_SLOTS; i++) {
				if ((fas->f_throttle[i] > HOLD_THROTTLE) &&
				    (fas->f_active[i] &&
				    (fas->f_active[i]->f_slot[0] == NULL))) {
					fas_full_throttle(fas, i);
				}
			}
		}

		if (fas->f_props_update) {
			int i;
			/*
			 * f_mutex will be released and reentered in
			 * fas_props_update().
			 * Hence we save the fas->f_props_update now and
			 * set to 0 indicating that property has been
			 * updated. This will avoid a race condition with
			 * any thread that runs in interrupt context that
			 * attempts to set the f_props_update to non-zero value
			 */
			props_update = fas->f_props_update;
			fas->f_props_update = 0;
			for (i = 0; i < NTARGETS_WIDE; i++) {
				if (props_update & (1<<i)) {
					fas_update_props(fas, i);
				}
			}
		}
		fas_check_waitQ_and_mutex_exit(fas);

	}
	rw_exit(&fas_global_rwlock);

again:
	mutex_enter(&fas_global_mutex);
	if (fas_timeout_initted && fas_timeout_id) {
		fas_timeout_id = timeout(fas_watch, NULL, fas_tick);
	}
	mutex_exit(&fas_global_mutex);
	TRACE_0(TR_FAC_SCSI_FAS, TR_FAS_WATCH_END, "fas_watch_end");
}

static void
fas_watchsubr(struct fas *fas)
{
	short slot;
	int d = ((fas->f_dslot == 0)? 1 : fas->f_dslot);
	struct f_slots *tag_slots;

	for (slot = 0; slot < N_SLOTS; slot += d)  {

#ifdef FAS_TEST
		if (fas_btest) {
			fas_btest = 0;
			(void) fas_reset_bus(fas);
			return;
		}
		if (fas_force_timeout && fas->f_tcmds[slot]) {
			fas_cmd_timeout(fas, slot);
			fas_force_timeout = 0;
			return;
		}
		fas_test_reset(fas, slot);
		fas_test_abort(fas, slot);
#endif /* FAS_TEST */

		/*
		 * check tagged cmds first
		 */
		tag_slots = fas->f_active[slot];
		DPRINTF3(
		"fas_watchsubr: slot %x: tcmds=%x, timeout=%x\n",
		    slot, fas->f_tcmds[slot], tag_slots->f_timeout);

		if ((fas->f_tcmds[slot] > 0) && (tag_slots->f_timebase)) {

			if (tag_slots->f_timebase <=
			    fas_scsi_watchdog_tick) {
				tag_slots->f_timebase +=
				    fas_scsi_watchdog_tick;
				continue;
			}

			tag_slots->f_timeout -= fas_scsi_watchdog_tick;

			if (tag_slots->f_timeout < 0) {
				fas_cmd_timeout(fas, slot);
				return;
			}
			if ((tag_slots->f_timeout) <=
			    fas_scsi_watchdog_tick) {
				IPRINTF1("pending timeout on slot=%x\n",
				    slot);
				IPRINTF("draining all queues\n");
				fas_set_throttles(fas, 0, N_SLOTS,
				    DRAIN_THROTTLE);
			}
		}
	}
}

/*
 * timeout recovery
 */
static void
fas_cmd_timeout(struct fas *fas, int slot)
{
	int d = ((fas->f_dslot == 0)? 1 : fas->f_dslot);
	int target, lun, i, n, tag, ncmds;
	struct fas_cmd *sp = NULL;
	struct fas_cmd *ssp;

	ASSERT(fas->f_tcmds[slot]);

#ifdef FAS_TEST
	if (fas_test_stop) {
		debug_enter("timeout");
	}
#endif

	/*
	 * set throttle back; no more draining necessary
	 */
	for (i = 0; i < N_SLOTS; i += d) {
		if (fas->f_throttle[i] == DRAIN_THROTTLE) {
			fas_full_throttle(fas, i);
		}
	}

	if (NOTAG(slot/NLUNS_PER_TARGET)) {
		sp = fas->f_active[slot]->f_slot[0];
	}

	/*
	 * if no interrupt pending for next second then the current
	 * cmd must be stuck; switch slot and sp to current slot and cmd
	 */
	if (fas->f_current_sp && fas->f_state != STATE_FREE) {
		for (i = 0; (i < 10000) && (INTPENDING(fas) == 0); i++) {
			drv_usecwait(100);
		}
		if (INTPENDING(fas) == 0) {
			slot = fas->f_current_sp->cmd_slot;
			sp = fas->f_current_sp;
		}
	}

	target = slot / NLUNS_PER_TARGET;
	lun = slot % NLUNS_PER_TARGET;

	/*
	 * update all outstanding  pkts for this slot
	 */
	n = fas->f_active[slot]->f_n_slots;
	for (ncmds = tag = 0; tag < n; tag++) {
		ssp = fas->f_active[slot]->f_slot[tag];
		if (ssp && ssp->cmd_pkt->pkt_time) {
			fas_set_pkt_reason(fas, ssp, CMD_TIMEOUT,
			    STAT_TIMEOUT | STAT_ABORTED);
			fas_short_dump_cmd(fas, ssp);
			ncmds++;
		}
	}

	/*
	 * no timed-out cmds here?
	 */
	if (ncmds == 0) {
		return;
	}

	/*
	 * dump all we know about this timeout
	 */
	if (sp) {
		if (sp->cmd_flags & CFLAG_CMDDISC) {
			fas_log(fas, CE_WARN,
			    "Disconnected command timeout for Target %d.%d",
			    target, lun);
		} else {
			ASSERT(sp == fas->f_current_sp);
			fas_log(fas, CE_WARN,
			    "Connected command timeout for Target %d.%d",
			    target, lun);
			/*
			 * Current command timeout appears to relate often
			 * to noisy SCSI in synchronous mode.
			 */
			if (fas->f_state == ACTS_DATA_DONE) {
				fas_sync_wide_backoff(fas, sp, slot);
			}
		}
#ifdef FASDEBUG
		fas_printstate(fas, "timeout");
#endif
	} else {
		fas_log(fas, CE_WARN,
		    "Disconnected tagged cmd(s) (%d) timeout for Target %d.%d",
		    fas->f_tcmds[slot], target, lun);
	}

	if (fas_abort_cmd(fas, sp, slot) == ACTION_SEARCH) {
		(void) fas_istart(fas);
	}
}

/*
 * fas_sync_wide_backoff() increases sync period and enables slow
 * cable mode.
 * the second time, we revert back to narrow/async
 * we count on a bus reset to disable wide in the target and will
 * never renegotiate wide again
 */
static void
fas_sync_wide_backoff(struct fas *fas, struct fas_cmd *sp,
    int slot)
{
	char phase;
	ushort_t state = fas->f_state;
	uchar_t tgt = slot / NLUNS_PER_TARGET;
	uint_t tshift = 1 << tgt;

	phase = fas_reg_read(fas, &fas->f_reg->fas_stat);
	phase &=  FAS_PHASE_MASK;

	IPRINTF4(
	"fas_sync_wide_backoff: target %d: state=%x, phase=%x, sp=0x%p\n",
	    tgt, state, phase, (void *)sp);

#ifdef FASDEBUG
	if (fas_no_sync_wide_backoff) {
		return;
	}
#endif

	/*
	 * if this not the first time or sync is disabled
	 * thru scsi_options then disable wide
	 */
	if ((fas->f_backoff & tshift) ||
	    (fas->f_nosync & tshift)) {
		/*
		 * disable wide for just this target
		 */
		if ((fas->f_nowide & tshift) == 0) {
			fas_log(fas, CE_WARN,
			    "Target %d disabled wide SCSI mode", tgt);
		}
		/*
		 * do not reset the bit in f_nowide because that
		 * would not force a renegotiation of wide
		 * and do not change any register value yet because
		 * we may have reconnects before the renegotiations
		 */
		fas->f_target_scsi_options[tgt] &= ~SCSI_OPTIONS_WIDE;
	}

	/*
	 * reduce xfer rate. if this is the first time, reduce by
	 * 100%. second time, disable sync and wide.
	 */
	if (fas->f_offset[tgt] != 0) {
		/*
		 * do not reset the bit in f_nosync because that
		 * would not force a renegotiation of sync
		 */
		if (fas->f_backoff & tshift) {
			if ((fas->f_nosync & tshift) == 0) {
				fas_log(fas, CE_WARN,
				    "Target %d reverting to async. mode",
				    tgt);
			}
			fas->f_target_scsi_options[tgt] &=
			    ~(SCSI_OPTIONS_SYNC | SCSI_OPTIONS_FAST);
		} else {
			/* increase period by 100% */
			fas->f_neg_period[tgt] *= 2;

			fas_log(fas, CE_WARN,
			    "Target %d reducing sync. transfer rate", tgt);
		}
	}
	fas->f_backoff |= tshift;

	/*
	 * always enable slow cable mode, if not already enabled
	 */
	if ((fas->f_fasconf & FAS_CONF_SLOWMODE) == 0) {
		fas->f_fasconf |= FAS_CONF_SLOWMODE;
		fas_reg_write(fas, &fas->f_reg->fas_conf, fas->f_fasconf);
		IPRINTF("Reverting to slow SCSI cable mode\n");
	}

	/*
	 * Force sync renegotiation and update properties
	 */
	fas_force_renegotiation(fas, tgt);
	fas->f_props_update |= (1<<tgt);
}

/*
 * handle failed negotiations (either reject or bus free condition)
 */
static void
fas_reset_sync_wide(struct fas *fas)
{
	struct fas_cmd *sp = fas->f_current_sp;
	int tgt = Tgt(sp);

	if (fas->f_wdtr_sent) {
		IPRINTF("wide neg message rejected or bus free\n");
		fas->f_nowide |= (1<<tgt);
		fas->f_fasconf3[tgt] &= ~FAS_CONF3_WIDE;
		fas_reg_write(fas, &fas->f_reg->fas_conf3,
		    fas->f_fasconf3[tgt]);
		/*
		 * clear offset just in case it goes to
		 * data phase
		 */
		fas_reg_write(fas,
		    (uchar_t *)&fas->f_reg->fas_sync_offset, 0);
	} else if (fas->f_sdtr_sent) {
		volatile struct fasreg *fasreg =
		    fas->f_reg;
		IPRINTF("sync neg message rejected or bus free\n");
		fas->f_nosync |= (1<<tgt);
		fas->f_offset[tgt] = 0;
		fas->f_sync_period[tgt] = 0;
		fas_reg_write(fas,
		    (uchar_t *)&fasreg->fas_sync_period, 0);
		fas_reg_write(fas,
		    (uchar_t *)&fasreg->fas_sync_offset, 0);
		fas->f_offset[tgt] = 0;
		fas->f_fasconf3[tgt] &= ~FAS_CONF3_FASTSCSI;
		fas_reg_write(fas, &fasreg->fas_conf3,
		    fas->f_fasconf3[tgt]);
	}

	fas_force_renegotiation(fas, tgt);
}

/*
 * force wide and sync renegotiation
 */
static void
fas_force_renegotiation(struct fas *fas, int target)
{
	ushort_t tshift = 1<<target;
	fas->f_sync_known &= ~tshift;
	fas->f_sync_enabled &= ~tshift;
	fas->f_wide_known &= ~tshift;
	fas->f_wide_enabled &= ~tshift;
}

/*
 * update conf3 register for wide negotiation
 */
static void
fas_set_wide_conf3(struct fas *fas, int target, int width)
{
	ASSERT(width <= 1);
	switch (width) {
	case 0:
		fas->f_fasconf3[target] &= ~FAS_CONF3_WIDE;
		break;
	case 1:
		fas->f_fasconf3[target] |= FAS_CONF3_WIDE;
		fas->f_wide_enabled |= (1<<target);
		break;
	}

	fas_reg_write(fas, &fas->f_reg->fas_conf3, fas->f_fasconf3[target]);
	fas->f_fasconf3_reg_last = fas->f_fasconf3[target];
}

/*
 * Abort command handling
 *
 * abort current cmd, either by device reset or immediately with bus reset
 * (usually an abort msg doesn't completely solve the problem, therefore
 * a device or bus reset is recommended)
 */
static int
fas_abort_curcmd(struct fas *fas)
{
	if (fas->f_current_sp) {
		return (fas_abort_cmd(fas, fas->f_current_sp,
		    fas->f_current_sp->cmd_slot));
	} else {
		return (fas_reset_bus(fas));
	}
}

static int
fas_abort_cmd(struct fas *fas, struct fas_cmd *sp, int slot)
{
	struct scsi_address ap;

	ap.a_hba_tran = fas->f_tran;
	ap.a_target = slot / NLUNS_PER_TARGET;
	ap.a_lun    = slot % NLUNS_PER_TARGET;

	IPRINTF1("abort cmd 0x%p\n", (void *)sp);

	/*
	 * attempting to abort a connected cmd is usually fruitless, so
	 * only try disconnected cmds
	 * a reset is preferable over an abort (see 1161701)
	 */
	if ((fas->f_current_sp && (fas->f_current_sp->cmd_slot != slot)) ||
	    (fas->f_state == STATE_FREE)) {
		IPRINTF2("attempting to reset target %d.%d\n",
		    ap.a_target, ap.a_lun);
		if (fas_do_scsi_reset(&ap, RESET_TARGET)) {
			return (ACTION_SEARCH);
		}
	}

	/*
	 * if the target won't listen, then a retry is useless
	 * there is also the possibility that the cmd still completed while
	 * we were trying to reset and the target driver may have done a
	 * device reset which has blown away this sp.
	 * well, we've tried, now pull the chain
	 */
	IPRINTF("aborting all cmds by bus reset\n");
	return (fas_reset_bus(fas));
}

/*
 * fas_do_scsi_abort() assumes that we already have the mutex.
 * during the abort, we hold the mutex and prevent callbacks by setting
 * completion pointer to NULL. this will also avoid that a target driver
 * attempts to do a scsi_abort/reset while we are aborting.
 * because the completion pointer is NULL  we can still update the
 * packet after completion
 * the throttle for this slot is cleared either by fas_abort_connected_cmd
 * or fas_runpoll which prevents new cmds from starting while aborting
 */
static int
fas_do_scsi_abort(struct scsi_address *ap, struct scsi_pkt *pkt)
{
	struct fas *fas = ADDR2FAS(ap);
	struct fas_cmd *sp;
	int rval = FALSE;
	short slot;
	struct fas_cmd *cur_sp = fas->f_current_sp;
	void	(*cur_savec)(), (*sp_savec)();
	int	sp_tagged_flag, abort_msg;

	if (pkt) {
		sp = PKT2CMD(pkt);
		slot = sp->cmd_slot;
		ASSERT(slot == ((ap->a_target * NLUNS_PER_TARGET) | ap->a_lun));
	} else {
		sp = NULL;
		slot = (ap->a_target * NLUNS_PER_TARGET) | ap->a_lun;
	}

	fas_move_waitQ_to_readyQ(fas);

	/*
	 *   If no specific command was passed, all cmds here will be aborted
	 *   If a specific command was passed as an argument (to be aborted)
	 *   only the specified command will be aborted
	 */
	ASSERT(mutex_owned(FAS_MUTEX(fas)));
	IPRINTF4("fas_scsi_abort for slot %x, "
	    "sp=0x%p, pkt_flags=%x, cur_sp=0x%p\n",
	    slot, (void *)sp, (sp? sp->cmd_pkt_flags : 0), (void *)cur_sp);

	/*
	 * first check if the cmd is in the ready queue or
	 * in the active queue
	 */
	if (sp) {
		IPRINTF3("aborting one command 0x%p for %d.%d\n",
		    (void *)sp, ap->a_target, ap->a_lun);
		rval = fas_remove_from_readyQ(fas, sp, slot);
		if (rval) {
			IPRINTF("aborted one ready cmd\n");
			fas_set_pkt_reason(fas, sp, CMD_ABORTED, STAT_ABORTED);
			fas_decrement_ncmds(fas, sp);
			fas_call_pkt_comp(fas, sp);
			goto exit;

		} else if ((sp !=
		    fas->f_active[slot]->f_slot[sp->cmd_tag[1]])) {
			IPRINTF("cmd doesn't exist here\n");
			rval = TRUE;
			goto exit;
		}
	}

	/*
	 * hold off any new commands while attempting to abort
	 * an active cmd
	 */
	fas_set_throttles(fas, slot, 1, HOLD_THROTTLE);

	if (cur_sp) {
		/*
		 * prevent completion on current cmd
		 */
		cur_savec = cur_sp->cmd_pkt->pkt_comp;
		cur_sp->cmd_pkt->pkt_comp = NULL;
	}

	if (sp) {
		/*
		 * the cmd exists here. is it connected or disconnected?
		 * if connected but still selecting then can't abort now.
		 * prevent completion on this cmd
		 */
		sp_tagged_flag = (sp->cmd_pkt_flags & FLAG_TAGMASK);
		abort_msg = (sp_tagged_flag? MSG_ABORT_TAG : MSG_ABORT);
		sp_savec = sp->cmd_pkt->pkt_comp;
		sp->cmd_pkt->pkt_comp = NULL;

		/* connected but not selecting? */
		if ((sp == cur_sp) && (fas->f_state != STATE_FREE) &&
		    (sp->cmd_pkt->pkt_state)) {
			rval = fas_abort_connected_cmd(fas, sp, abort_msg);
		}

		/* if abort connected cmd failed, try abort disconnected */
		if ((rval == 0) &&
		    (sp->cmd_flags & CFLAG_CMDDISC) &&
		    ((sp->cmd_flags &  CFLAG_COMPLETED) == 0)) {
			rval = fas_abort_disconnected_cmd(fas, ap, sp,
			    abort_msg, slot);
		}

		if (rval) {
			sp->cmd_flags |= CFLAG_COMPLETED;
			fas_set_pkt_reason(fas, sp, CMD_ABORTED, STAT_ABORTED);
		}

		sp->cmd_pkt->pkt_comp = sp_savec;

	} else {
		IPRINTF2("aborting all commands for %d.%d\n",
		    ap->a_target, ap->a_lun);
		abort_msg = MSG_ABORT;

		/* active and not selecting ? */
		if (cur_sp && (fas->f_state != STATE_FREE) &&
		    (cur_sp->cmd_slot == slot) &&
		    cur_sp->cmd_pkt->pkt_state) {
			rval = fas_abort_connected_cmd(fas, cur_sp,
			    abort_msg);
		}
		if (rval == 0) {
			rval = fas_abort_disconnected_cmd(fas, ap,
			    NULL, abort_msg, slot);
		}
	}

done:
	/* complete the current sp */
	if (cur_sp) {
		cur_sp->cmd_pkt->pkt_comp = cur_savec;
		if (cur_sp->cmd_flags & CFLAG_COMPLETED) {
			fas_remove_cmd(fas, cur_sp, NEW_TIMEOUT);
			cur_sp->cmd_flags &= ~CFLAG_COMPLETED;
			fas_decrement_ncmds(fas, cur_sp);
			fas_call_pkt_comp(fas, cur_sp);
		}
	}

	/* complete the sp passed as 2nd arg */
	if (sp && (sp != cur_sp) && (sp->cmd_flags & CFLAG_COMPLETED)) {
		sp->cmd_flags &= ~CFLAG_COMPLETED;
		fas_remove_cmd(fas, sp, NEW_TIMEOUT);
		fas_decrement_ncmds(fas, sp);
		fas_call_pkt_comp(fas, sp);
	}

	/* clean up all cmds for this slot */
	if (rval && (abort_msg == MSG_ABORT)) {
		/*
		 * mark all commands here as aborted
		 * abort msg has been accepted, now cleanup queues;
		 */
		fas_mark_packets(fas, slot, CMD_ABORTED, STAT_ABORTED);
		fas_flush_tagQ(fas, slot);
		fas_flush_readyQ(fas, slot);
	}
	fas_set_throttles(fas, slot, 1, MAX_THROTTLE);

exit:
	if (fas->f_state == STATE_FREE) {
		(void) fas_ustart(fas);
	}

	ASSERT(mutex_owned(FAS_MUTEX(fas)));

#ifdef FASDEBUG
	if (rval && fas_test_stop) {
		debug_enter("abort succeeded");
	}
#endif
	return (rval);
}

/*
 * mark all packets with new reason and update statistics
 */
static void
fas_mark_packets(struct fas *fas, int slot, uchar_t reason, uint_t stat)
{
	struct fas_cmd *sp = fas->f_readyf[slot];

	while (sp != 0) {
		fas_set_pkt_reason(fas, sp, reason, STAT_ABORTED);
		sp = sp->cmd_forw;
	}
	if (fas->f_tcmds[slot]) {
		int n = 0;
		ushort_t tag;

		for (tag = 0; tag < fas->f_active[slot]->f_n_slots; tag++) {
			if ((sp = fas->f_active[slot]->f_slot[tag]) != 0) {
				fas_set_pkt_reason(fas, sp, reason, stat);
				n++;
			}
		}
		ASSERT(fas->f_tcmds[slot] == n);
	}
}

/*
 * set pkt_reason and OR in pkt_statistics flag
 */
static void
fas_set_pkt_reason(struct fas *fas, struct fas_cmd *sp, uchar_t reason,
    uint_t stat)
{
	if (sp) {
		if (sp->cmd_pkt->pkt_reason == CMD_CMPLT) {
			sp->cmd_pkt->pkt_reason = reason;
		}
		sp->cmd_pkt->pkt_statistics |= stat;
		IPRINTF3("sp=0x%p, pkt_reason=%x, pkt_stat=%x\n",
		    (void *)sp, reason, sp->cmd_pkt->pkt_statistics);
	}
}

/*
 * delete specified cmd from the ready queue
 */
static int
fas_remove_from_readyQ(struct fas *fas, struct fas_cmd *sp, int slot)
{
	struct fas_cmd *ssp, *psp;

	/*
	 * command has not been started yet and is still in the ready queue
	 */
	if (sp) {
		ASSERT(fas->f_ncmds > 0);
		/*
		 * find packet on the ready queue and remove it
		 */
		for (psp = NULL, ssp = fas->f_readyf[slot]; ssp != NULL;
		    psp = ssp, ssp = ssp->cmd_forw) {
			if (ssp == sp) {
				if (fas->f_readyf[slot] == sp) {
					fas->f_readyf[slot] = sp->cmd_forw;
				} else {
					psp->cmd_forw = sp->cmd_forw;
				}
				if (fas->f_readyb[slot] == sp) {
					fas->f_readyb[slot] = psp;
				}
				return (TRUE);
			}
		}
	}
	return (FALSE);
}

/*
 * add cmd to to head of the readyQ
 * due to tag allocation failure or preemption we have to return
 * this cmd to the readyQ
 */
static void
fas_head_of_readyQ(struct fas *fas, struct fas_cmd *sp)
{
	/*
	 * never return a NOINTR pkt to the readyQ
	 * (fas_runpoll will resubmit)
	 */
	if ((sp->cmd_pkt_flags & FLAG_NOINTR) == 0) {
		struct fas_cmd *dp;
		int slot = sp->cmd_slot;

		dp = fas->f_readyf[slot];
		fas->f_readyf[slot] = sp;
		sp->cmd_forw = dp;
		if (fas->f_readyb[slot] == NULL) {
			fas->f_readyb[slot] = sp;
		}
	}
}

/*
 * flush cmds in ready queue
 */
static void
fas_flush_readyQ(struct fas *fas, int slot)
{
	if (fas->f_readyf[slot]) {
		struct fas_cmd *sp, *nsp;

		IPRINTF1("flushing ready queue, slot=%x\n", slot);
		ASSERT(fas->f_ncmds > 0);

		sp = fas->f_readyf[slot];
		fas->f_readyf[slot] = fas->f_readyb[slot] = NULL;

		while (sp != 0) {
			/*
			 * save the forward pointer before calling
			 * the completion routine
			 */
			nsp = sp->cmd_forw;
			ASSERT((sp->cmd_flags & CFLAG_FREE) == 0);
			ASSERT(Tgt(sp) == slot/NLUNS_PER_TARGET);
			fas_decrement_ncmds(fas, sp);
			fas_call_pkt_comp(fas, sp);
			sp = nsp;
		}
		fas_check_ncmds(fas);
	}
}

/*
 * cleanup the tag queue
 * preserve some order by starting with the oldest tag
 */
static void
fas_flush_tagQ(struct fas *fas, int slot)
{
	ushort_t tag, starttag;
	struct fas_cmd *sp;
	struct f_slots *tagque = fas->f_active[slot];

	if (tagque == NULL) {
		return;
	}

	DPRINTF2("flushing entire tag queue, slot=%x, tcmds=%x\n",
	    slot, fas->f_tcmds[slot]);

#ifdef FASDEBUG
	{
		int n = 0;
		for (tag = 0; tag < fas->f_active[slot]->f_n_slots; tag++) {
			if ((sp = tagque->f_slot[tag]) != 0) {
				n++;
				ASSERT((sp->cmd_flags & CFLAG_FREE) == 0);
				if (sp->cmd_pkt->pkt_reason == CMD_CMPLT) {
					if ((sp->cmd_flags & CFLAG_FINISHED) ==
					    0) {
						debug_enter("fas_flush_tagQ");
					}
				}
			}
		}
		ASSERT(fas->f_tcmds[slot] == n);
	}
#endif
	tag = starttag = fas->f_active[slot]->f_tags;

	do {
		if ((sp = tagque->f_slot[tag]) != 0) {
			fas_flush_cmd(fas, sp, 0, 0);
		}
		tag = ((ushort_t)(tag + 1)) %
		    (ushort_t)fas->f_active[slot]->f_n_slots;
	} while (tag != starttag);

	ASSERT(fas->f_tcmds[slot] == 0);
	EPRINTF2("ncmds = %x, ndisc=%x\n", fas->f_ncmds, fas->f_ndisc);
	fas_check_ncmds(fas);
}

/*
 * cleanup one active command
 */
static void
fas_flush_cmd(struct fas *fas, struct fas_cmd *sp, uchar_t reason,
    uint_t stat)
{
	short slot = sp->cmd_slot;

	ASSERT(fas->f_ncmds > 0);
	ASSERT((sp->cmd_flags & CFLAG_FREE) == 0);
	ASSERT(sp == fas->f_active[slot]->f_slot[sp->cmd_tag[1]]);

	fas_remove_cmd(fas, sp, NEW_TIMEOUT);
	fas_decrement_ncmds(fas, sp);
	fas_set_pkt_reason(fas, sp, reason, stat);
	fas_call_pkt_comp(fas, sp);

	EPRINTF2("ncmds = %x, ndisc=%x\n", fas->f_ncmds, fas->f_ndisc);
	fas_check_ncmds(fas);
}

/*
 * prepare a proxy cmd (a cmd sent on behalf of the target driver,
 * usually for error recovery or abort/reset)
 */
static void
fas_makeproxy_cmd(struct fas_cmd *sp, struct scsi_address *ap,
    struct scsi_pkt *pkt, int nmsgs, ...)
{
	va_list vap;
	int i;

	ASSERT(nmsgs <= (CDB_GROUP5 - CDB_GROUP0 - 3));

	bzero(sp, sizeof (*sp));
	bzero(pkt, scsi_pkt_size());

	pkt->pkt_address	= *ap;
	pkt->pkt_cdbp		= (opaque_t)&sp->cmd_cdb[0];
	pkt->pkt_scbp		= (opaque_t)&sp->cmd_scb;
	pkt->pkt_ha_private	= (opaque_t)sp;
	sp->cmd_pkt		= pkt;
	sp->cmd_scblen		= 1;
	sp->cmd_pkt_flags	= pkt->pkt_flags = FLAG_NOINTR;
	sp->cmd_flags		= CFLAG_CMDPROXY;
	sp->cmd_cdb[FAS_PROXY_TYPE] = FAS_PROXY_SNDMSG;
	sp->cmd_cdb[FAS_PROXY_RESULT] = FALSE;
	sp->cmd_cdb[FAS_PROXY_DATA] = (char)nmsgs;

	va_start(vap, nmsgs);
	for (i = 0; i < nmsgs; i++) {
		sp->cmd_cdb[FAS_PROXY_DATA + 1 + i] = (uchar_t)va_arg(vap, int);
	}
	va_end(vap);
}

/*
 * send a proxy cmd and check the result
 */
static int
fas_do_proxy_cmd(struct fas *fas, struct fas_cmd *sp,
    struct scsi_address *ap, char *what)
{
	int rval;

	IPRINTF3("Sending proxy %s message to %d.%d\n", what,
	    ap->a_target, ap->a_lun);
	if (fas_accept_pkt(fas, sp, TRAN_BUSY_OK) == TRAN_ACCEPT &&
	    sp->cmd_pkt->pkt_reason == CMD_CMPLT &&
	    sp->cmd_cdb[FAS_PROXY_RESULT] == TRUE) {
		IPRINTF3("Proxy %s succeeded for %d.%d\n", what,
		    ap->a_target, ap->a_lun);
		ASSERT(fas->f_current_sp != sp);
		rval = TRUE;
	} else {
		IPRINTF5(
		"Proxy %s failed for %d.%d, result=%x, reason=%x\n", what,
		    ap->a_target, ap->a_lun, sp->cmd_cdb[FAS_PROXY_RESULT],
		    sp->cmd_pkt->pkt_reason);
		ASSERT(fas->f_current_sp != sp);
		rval = FALSE;
	}
	return (rval);
}

/*
 * abort a connected command by sending an abort msg; hold off on
 * starting new cmds by setting throttles to HOLD_THROTTLE
 */
static int
fas_abort_connected_cmd(struct fas *fas, struct fas_cmd *sp, uchar_t msg)
{
	int rval = FALSE;
	int flags = sp->cmd_pkt_flags;

	/*
	 * if reset delay active we cannot  access the target.
	 */
	if (fas->f_reset_delay[Tgt(sp)]) {
		return (rval);
	}

	/*
	 * only abort while in data phase; otherwise we mess up msg phase
	 */
	if (!((fas->f_state == ACTS_DATA) ||
	    (fas->f_state == ACTS_DATA_DONE))) {
		return (rval);
	}


	IPRINTF3("Sending abort message %s to connected %d.%d\n",
	    scsi_mname(msg), Tgt(sp), Lun(sp));


	fas->f_abort_msg_sent = 0;
	fas->f_omsglen = 1;
	fas->f_cur_msgout[0] = msg;
	sp->cmd_pkt_flags |= FLAG_NOINTR;
	fas_assert_atn(fas);

	(void) fas_dopoll(fas, SHORT_POLL_TIMEOUT);

	/*
	 * now check if the msg was taken
	 * e_abort is set in fas_handle_msg_out_done when the abort
	 * msg has actually gone out (ie. msg out phase occurred
	 */
	if (fas->f_abort_msg_sent && (sp->cmd_flags & CFLAG_COMPLETED)) {
		IPRINTF2("target %d.%d aborted\n",
		    Tgt(sp), Lun(sp));
		rval = TRUE;
	} else {
		IPRINTF2("target %d.%d did not abort\n",
		    Tgt(sp), Lun(sp));
	}
	sp->cmd_pkt_flags = flags;
	fas->f_omsglen = 0;
	return (rval);
}

/*
 * abort a disconnected command; if it is a tagged command, we need
 * to include the tag
 */
static int
fas_abort_disconnected_cmd(struct fas *fas, struct scsi_address *ap,
    struct fas_cmd *sp, uchar_t msg, int slot)
{
	auto struct fas_cmd	local;
	struct fas_cmd		*proxy_cmdp = &local;
	struct scsi_pkt		*pkt;
	int			rval;
	int			target = ap->a_target;

	/*
	 * if reset delay is active, we cannot start a selection
	 * and there shouldn't be a cmd outstanding
	 */
	if (fas->f_reset_delay[target] != 0) {
		return (FALSE);
	}

	if (sp)
		ASSERT(sp->cmd_slot == slot);

	IPRINTF1("aborting disconnected tagged cmd(s) with %s\n",
	    scsi_mname(msg));
	pkt = kmem_alloc(scsi_pkt_size(), KM_SLEEP);
	if (sp && (TAGGED(target) && (msg == MSG_ABORT_TAG))) {
		int tag = sp->cmd_tag[1];
		ASSERT(sp == fas->f_active[slot]->f_slot[tag]);
		fas_makeproxy_cmd(proxy_cmdp, ap, pkt, 3,
		    MSG_SIMPLE_QTAG, tag, msg);
	} else {
		fas_makeproxy_cmd(proxy_cmdp, ap, pkt, 1, msg);
	}

	rval = fas_do_proxy_cmd(fas, proxy_cmdp, ap, scsi_mname(msg));
	kmem_free(pkt, scsi_pkt_size());
	return (rval);
}

/*
 * reset handling:
 * fas_do_scsi_reset assumes that we have already entered the mutex
 */
static int
fas_do_scsi_reset(struct scsi_address *ap, int level)
{
	int rval = FALSE;
	struct fas *fas = ADDR2FAS(ap);
	short slot = (ap->a_target * NLUNS_PER_TARGET) | ap->a_lun;

	ASSERT(mutex_owned(FAS_MUTEX(fas)));
	IPRINTF3("fas_scsi_reset for slot %x, level=%x, tcmds=%x\n",
	    slot, level, fas->f_tcmds[slot]);

	fas_move_waitQ_to_readyQ(fas);

	if (level == RESET_ALL) {
		/*
		 * We know that fas_reset_bus() returns ACTION_RETURN.
		 */
		(void) fas_reset_bus(fas);

		/*
		 * Now call fas_dopoll() to field the reset interrupt
		 * which will then call fas_reset_recovery which will
		 * call the completion function for all commands.
		 */
		if (fas_dopoll(fas, SHORT_POLL_TIMEOUT) <= 0) {
			/*
			 * reset fas
			 */
			fas_internal_reset(fas, FAS_RESET_FAS);
			(void) fas_reset_bus(fas);
			if (fas_dopoll(fas, SHORT_POLL_TIMEOUT) <= 0) {
				fas_log(fas,
				    CE_WARN, "reset scsi bus failed");
				New_state(fas, STATE_FREE);
			} else {
				rval = TRUE;
			}
		} else {
			rval = TRUE;
		}

	} else {
		struct fas_cmd *cur_sp = fas->f_current_sp;
		void (*savec)() = NULL;

		/*
		 * prevent new commands from starting
		 */
		fas_set_all_lun_throttles(fas, slot, HOLD_THROTTLE);

		/*
		 * zero pkt_comp so it won't complete during the reset and
		 * we can still update the packet after the reset.
		 */
		if (cur_sp) {
			savec = cur_sp->cmd_pkt->pkt_comp;
			cur_sp->cmd_pkt->pkt_comp = NULL;
		}

		/*
		 * is this a connected cmd but not selecting?
		 */
		if (cur_sp && (fas->f_state != STATE_FREE) &&
		    (cur_sp->cmd_pkt->pkt_state != 0) &&
		    (ap->a_target == (Tgt(cur_sp)))) {
			rval = fas_reset_connected_cmd(fas, ap);
		}

		/*
		 * if not connected or fas_reset_connected_cmd() failed,
		 * attempt a reset_disconnected_cmd
		 */
		if (rval == FALSE) {
			rval = fas_reset_disconnected_cmd(fas, ap);
		}

		/*
		 * cleanup if reset was successful
		 * complete the current sp first.
		 */
		if (cur_sp) {
			cur_sp->cmd_pkt->pkt_comp = savec;
			if (cur_sp->cmd_flags & CFLAG_COMPLETED) {
				if (ap->a_target == (Tgt(cur_sp))) {
					fas_set_pkt_reason(fas, cur_sp,
					    CMD_RESET, STAT_DEV_RESET);
				}
				fas_remove_cmd(fas, cur_sp, NEW_TIMEOUT);
				cur_sp->cmd_flags &= ~CFLAG_COMPLETED;
				fas_decrement_ncmds(fas, cur_sp);
				fas_call_pkt_comp(fas, cur_sp);
			}
		}

		if (rval == TRUE) {
			fas_reset_cleanup(fas, slot);
		} else {
			IPRINTF1("fas_scsi_reset failed for slot %x\n", slot);

			/*
			 * restore throttles to max throttle, regardless
			 * of what it was (fas_set_throttles() will deal
			 * with reset delay active)
			 * restoring to the old throttle is not
			 * a such a good idea
			 */
			fas_set_all_lun_throttles(fas, slot, MAX_THROTTLE);

		}

		if (fas->f_state == STATE_FREE) {
			(void) fas_ustart(fas);
		}
	}
exit:
	ASSERT(mutex_owned(FAS_MUTEX(fas)));
	ASSERT(fas->f_ncmds >= fas->f_ndisc);

#ifdef FASDEBUG
	if (rval && fas_test_stop) {
		debug_enter("reset succeeded");
	}
#endif
	return (rval);
}

/*
 * reset delay is  handled by a separate watchdog; this ensures that
 * regardless of fas_scsi_watchdog_tick, the reset delay will not change
 */
static void
fas_start_watch_reset_delay(struct fas *fas)
{
	mutex_enter(&fas_global_mutex);
	if ((fas_reset_watch == 0) && FAS_CAN_SCHED) {
		fas_reset_watch = timeout(fas_watch_reset_delay, NULL,
		    drv_usectohz((clock_t)FAS_WATCH_RESET_DELAY_TICK * 1000));
	}
	ASSERT((fas_reset_watch != 0) || (fas->f_flags & FAS_FLG_NOTIMEOUTS));
	mutex_exit(&fas_global_mutex);
}

/*
 * set throttles to HOLD and set reset_delay for all target/luns
 */
static void
fas_setup_reset_delay(struct fas *fas)
{
	if (!ddi_in_panic()) {
		int i;

		fas_set_throttles(fas, 0, N_SLOTS, HOLD_THROTTLE);
		for (i = 0; i < NTARGETS_WIDE; i++) {
			fas->f_reset_delay[i] = fas->f_scsi_reset_delay;
		}
		fas_start_watch_reset_delay(fas);
	} else {
		drv_usecwait(fas->f_scsi_reset_delay * 1000);
	}
}

/*
 * fas_watch_reset_delay(_subr) is invoked by timeout() and checks every
 * fas instance for active reset delays
 */
/*ARGSUSED*/
static void
fas_watch_reset_delay(void *arg)
{
	struct fas *fas;
	struct fas *lfas;	/* last not_done fas */
	int not_done = 0;

	mutex_enter(&fas_global_mutex);
	fas_reset_watch = 0;
	mutex_exit(&fas_global_mutex);

	rw_enter(&fas_global_rwlock, RW_READER);
	for (fas = fas_head; fas != (struct fas *)NULL; fas = fas->f_next) {
		if (fas->f_tran == 0) {
			continue;
		}
		mutex_enter(FAS_MUTEX(fas));
		not_done += fas_watch_reset_delay_subr(fas);
		lfas = fas;
		fas_check_waitQ_and_mutex_exit(fas);
	}
	rw_exit(&fas_global_rwlock);
	if (not_done) {
		ASSERT(lfas != NULL);
		fas_start_watch_reset_delay(lfas);
	}
}

static int
fas_watch_reset_delay_subr(struct fas *fas)
{
	short slot, s;
	int start_slot = -1;
	int done = 0;

	for (slot = 0; slot < N_SLOTS; slot += NLUNS_PER_TARGET)  {

		/*
		 * check if a reset delay is active; if so back to full throttle
		 * which will unleash the cmds in the ready Q
		 */
		s = slot/NLUNS_PER_TARGET;
		if (fas->f_reset_delay[s] != 0) {
			EPRINTF2("target%d: reset delay=%d\n", s,
			    fas->f_reset_delay[s]);
			fas->f_reset_delay[s] -= FAS_WATCH_RESET_DELAY_TICK;
			if (fas->f_reset_delay[s] <= 0) {
				/*
				 * clear throttle for all luns on  this target
				 */
				fas->f_reset_delay[s] = 0;
				fas_set_all_lun_throttles(fas,
				    slot, MAX_THROTTLE);
				IPRINTF1("reset delay completed, slot=%x\n",
				    slot);
				if (start_slot == -1) {
					start_slot = slot;
				}
			} else {
				done = -1;
			}
		}
	}

	/*
	 * start a cmd if a reset delay expired
	 */
	if (start_slot != -1 && fas->f_state == STATE_FREE) {
		(void) fas_ustart(fas);
	}
	return (done);
}

/*
 * cleanup after a device reset. this affects all target's luns
 */
static void
fas_reset_cleanup(struct fas *fas, int slot)
{
	/*
	 * reset msg has been accepted, now cleanup queues;
	 * for all luns of this target
	 */
	int i, start, end;
	int target  = slot/NLUNS_PER_TARGET;

	start = slot & ~(NLUNS_PER_TARGET-1);
	end = start + NLUNS_PER_TARGET;
	IPRINTF4("fas_reset_cleanup: slot %x, start=%x, end=%x, tcmds=%x\n",
	    slot, start, end, fas->f_tcmds[slot]);

	ASSERT(!(fas->f_current_sp &&
	    (fas->f_current_sp->cmd_slot == slot) &&
	    (fas->f_state & STATE_SELECTING)));

	/*
	 * if we are not in panic set up a reset delay for this target,
	 * a zero throttle forces all new requests into the ready Q
	 */
	if (!ddi_in_panic()) {
		fas_set_all_lun_throttles(fas, start, HOLD_THROTTLE);
		fas->f_reset_delay[target] = fas->f_scsi_reset_delay;
		fas_start_watch_reset_delay(fas);
	} else {
		drv_usecwait(fas->f_scsi_reset_delay * 1000);
	}

	for (i = start; i < end; i++) {
		fas_mark_packets(fas, i, CMD_RESET, STAT_DEV_RESET);
		fas_flush_tagQ(fas, i);
		fas_flush_readyQ(fas, i);
		if (fas->f_arq_pkt[i]) {
			struct fas_cmd *sp = fas->f_arq_pkt[i];
			struct arq_private_data *arq_data =
			    (struct arq_private_data *)
			    (sp->cmd_pkt->pkt_private);
			if (sp->cmd_pkt->pkt_comp) {
				ASSERT(arq_data->arq_save_sp == NULL);
			}
		}
		ASSERT(fas->f_tcmds[i] == 0);
	}
	ASSERT(fas->f_ncmds >= fas->f_ndisc);

	fas_force_renegotiation(fas, target);
}

/*
 * reset a currently disconnected target
 */
static int
fas_reset_disconnected_cmd(struct fas *fas, struct scsi_address *ap)
{
	auto struct fas_cmd	local;
	struct fas_cmd		*sp = &local;
	struct scsi_pkt		*pkt;
	int			rval;

	pkt = kmem_alloc(scsi_pkt_size(), KM_SLEEP);
	fas_makeproxy_cmd(sp, ap, pkt, 1, MSG_DEVICE_RESET);
	rval = fas_do_proxy_cmd(fas, sp, ap, scsi_mname(MSG_DEVICE_RESET));
	kmem_free(pkt, scsi_pkt_size());
	return (rval);
}

/*
 * reset a target with a currently connected command
 * Assert ATN and send MSG_DEVICE_RESET, zero throttles temporarily
 * to prevent new cmds from starting regardless of the outcome
 */
static int
fas_reset_connected_cmd(struct fas *fas, struct scsi_address *ap)
{
	int rval = FALSE;
	struct fas_cmd *sp = fas->f_current_sp;
	int flags = sp->cmd_pkt_flags;

	/*
	 * only attempt to reset in data phase; during other phases
	 * asserting ATN may just cause confusion
	 */
	if (!((fas->f_state == ACTS_DATA) ||
	    (fas->f_state == ACTS_DATA_DONE))) {
		return (rval);
	}

	IPRINTF2("Sending reset message to connected %d.%d\n",
	    ap->a_target, ap->a_lun);
	fas->f_reset_msg_sent = 0;
	fas->f_omsglen = 1;
	fas->f_cur_msgout[0] = MSG_DEVICE_RESET;
	sp->cmd_pkt_flags |= FLAG_NOINTR;

	fas_assert_atn(fas);

	/*
	 * poll for interrupts until bus free
	 */
	(void) fas_dopoll(fas, SHORT_POLL_TIMEOUT);

	/*
	 * now check if the msg was taken
	 * f_reset is set in fas_handle_msg_out_done when
	 * msg has actually gone out  (ie. msg out phase occurred)
	 */
	if (fas->f_reset_msg_sent && (sp->cmd_flags & CFLAG_COMPLETED)) {
		IPRINTF2("target %d.%d reset\n", ap->a_target, ap->a_lun);
		rval = TRUE;
	} else {
		IPRINTF2("target %d.%d did not reset\n",
		    ap->a_target, ap->a_lun);
	}
	sp->cmd_pkt_flags = flags;
	fas->f_omsglen = 0;

	return (rval);
}

/*
 * reset the scsi bus to blow all commands away
 */
static int
fas_reset_bus(struct fas *fas)
{
	IPRINTF("fas_reset_bus:\n");
	New_state(fas, ACTS_RESET);

	fas_internal_reset(fas, FAS_RESET_SCSIBUS);

	/*
	 * Now that we've reset the SCSI bus, we'll take a SCSI RESET
	 * interrupt and use that to clean up the state of things.
	 */
	return (ACTION_RETURN);
}

/*
 * fas_reset_recovery is called on the reset interrupt and cleans
 * up all cmds (active or waiting)
 */
static int
fas_reset_recovery(struct fas *fas)
{
	short slot, start_slot;
	int i;
	int rval = ACTION_SEARCH;
	int max_loop = 0;

	IPRINTF("fas_reset_recovery:\n");
	fas_check_ncmds(fas);

	/*
	 * renegotiate wide and sync for all targets
	 */
	fas->f_sync_known = fas->f_wide_known = 0;

	/*
	 * reset dma engine
	 */
	FAS_FLUSH_DMA_HARD(fas);

	/*
	 * set throttles and reset delay
	 */
	fas_setup_reset_delay(fas);

	/*
	 * clear interrupts until they go away
	 */
	while (INTPENDING(fas) && (max_loop < FAS_RESET_SPIN_MAX_LOOP)) {
		volatile struct fasreg *fasreg = fas->f_reg;
		fas->f_stat = fas_reg_read(fas, &fasreg->fas_stat);
		fas->f_stat2 = fas_reg_read(fas, &fasreg->fas_stat2);
		fas->f_step = fas_reg_read(fas, &fasreg->fas_step);
		fas->f_intr = fas_reg_read(fas, &fasreg->fas_intr);
		drv_usecwait(FAS_RESET_SPIN_DELAY_USEC);
		max_loop++;
	}

	if (max_loop >= FAS_RESET_SPIN_MAX_LOOP) {
		fas_log(fas, CE_WARN, "Resetting SCSI bus failed");
	}

	fas_reg_cmd_write(fas, CMD_FLUSH);

	/*
	 * reset the chip, this shouldn't be necessary but sometimes
	 * we get a hang in the next data in phase
	 */
	fas_internal_reset(fas, FAS_RESET_FAS);

	/*
	 * reset was expected? if not, it must be external bus reset
	 */
	if (fas->f_state != ACTS_RESET) {
		if (fas->f_ncmds) {
			fas_log(fas, CE_WARN, "external SCSI bus reset");
		}
	}

	if (fas->f_ncmds == 0) {
		rval = ACTION_RETURN;
		goto done;
	}

	/*
	 * completely reset the state of the softc data.
	 */
	fas_internal_reset(fas, FAS_RESET_SOFTC);

	/*
	 * Hold the state of the host adapter open
	 */
	New_state(fas, ACTS_FROZEN);

	/*
	 * for right now just claim that all
	 * commands have been destroyed by a SCSI reset
	 * and let already set reason fields or callers
	 * decide otherwise for specific commands.
	 */
	start_slot = fas->f_next_slot;
	slot = start_slot;
	do {
		fas_check_ncmds(fas);
		fas_mark_packets(fas, slot, CMD_RESET, STAT_BUS_RESET);
		fas_flush_tagQ(fas, slot);
		fas_flush_readyQ(fas, slot);
		if (fas->f_arq_pkt[slot]) {
			struct fas_cmd *sp = fas->f_arq_pkt[slot];
			struct arq_private_data *arq_data =
			    (struct arq_private_data *)
			    (sp->cmd_pkt->pkt_private);
			if (sp->cmd_pkt->pkt_comp) {
				ASSERT(arq_data->arq_save_sp == NULL);
			}
		}
		slot = NEXTSLOT(slot, fas->f_dslot);
	} while (slot != start_slot);

	fas_check_ncmds(fas);

	/*
	 * reset timeouts
	 */
	for (i = 0; i < N_SLOTS; i++) {
		if (fas->f_active[i]) {
			fas->f_active[i]->f_timebase = 0;
			fas->f_active[i]->f_timeout = 0;
			fas->f_active[i]->f_dups = 0;
		}
	}

done:
	/*
	 * Move the state back to free...
	 */
	New_state(fas, STATE_FREE);
	ASSERT(fas->f_ncmds >= fas->f_ndisc);

	/*
	 * perform the reset notification callbacks that are registered.
	 */
	(void) scsi_hba_reset_notify_callback(&fas->f_mutex,
	    &fas->f_reset_notify_listf);

	/*
	 * if reset delay is still active a search is meaningless
	 * but do it anyway
	 */
	return (rval);
}

/*
 * hba_tran ops for quiesce and unquiesce
 */
static int
fas_scsi_quiesce(dev_info_t *dip)
{
	struct fas *fas;
	scsi_hba_tran_t *tran;

	tran = ddi_get_driver_private(dip);
	if ((tran == NULL) || ((fas = TRAN2FAS(tran)) == NULL)) {
		return (-1);
	}

	return (fas_quiesce_bus(fas));
}

static int
fas_scsi_unquiesce(dev_info_t *dip)
{
	struct fas *fas;
	scsi_hba_tran_t *tran;

	tran = ddi_get_driver_private(dip);
	if ((tran == NULL) || ((fas = TRAN2FAS(tran)) == NULL)) {
		return (-1);
	}

	return (fas_unquiesce_bus(fas));
}

#ifdef FAS_TEST
/*
 * torture test functions
 */
static void
fas_test_reset(struct fas *fas, int slot)
{
	struct scsi_address ap;
	char target = slot/NLUNS_PER_TARGET;

	if (fas_rtest & (1 << target)) {
		ap.a_hba_tran = fas->f_tran;
		ap.a_target = target;
		ap.a_lun = 0;
		if ((fas_rtest_type == 1) &&
		    (fas->f_state == ACTS_DATA_DONE)) {
			if (fas_do_scsi_reset(&ap, RESET_TARGET)) {
				fas_rtest = 0;
			}
		} else if ((fas_rtest_type == 2) &&
		    (fas->f_state == ACTS_DATA_DONE)) {
			if (fas_do_scsi_reset(&ap, RESET_ALL)) {
				fas_rtest = 0;
			}
		} else {
			if (fas_do_scsi_reset(&ap, RESET_TARGET)) {
				fas_rtest = 0;
			}
		}
	}
}

static void
fas_test_abort(struct fas *fas, int slot)
{
	struct fas_cmd *sp = fas->f_current_sp;
	struct scsi_address ap;
	char target = slot/NLUNS_PER_TARGET;
	struct scsi_pkt *pkt = NULL;

	if (fas_atest & (1 << target)) {
		ap.a_hba_tran = fas->f_tran;
		ap.a_target = target;
		ap.a_lun = 0;

		if ((fas_atest_disc == 0) && sp &&
		    (sp->cmd_slot == slot) &&
		    ((sp->cmd_flags & CFLAG_CMDDISC) == 0)) {
			pkt = sp->cmd_pkt;
		} else if ((fas_atest_disc == 1) && NOTAG(target)) {
			sp = fas->f_active[slot]->f_slot[0];
			if (sp && (sp->cmd_flags & CFLAG_CMDDISC)) {
				pkt = sp->cmd_pkt;
			}
		} else if ((fas_atest_disc == 1) && (sp == 0) &&
		    TAGGED(target) &&
		    (fas->f_tcmds[slot] != 0)) {
			int tag;
			/*
			 * find the oldest tag
			 */
			for (tag = NTAGS-1; tag >= 0; tag--) {
				if ((sp = fas->f_active[slot]->f_slot[tag])
				    != 0)
				break;
			}
			if (sp) {
				pkt = sp->cmd_pkt;
				ASSERT(sp->cmd_slot == slot);
			} else {
				return;
			}
		} else if (fas_atest_disc == 2 && (sp == 0) &&
		    (fas->f_tcmds[slot] != 0)) {
			pkt = NULL;
		} else if (fas_atest_disc == 2 && NOTAG(target)) {
			pkt = NULL;
		} else if (fas_atest_disc == 3 && fas->f_readyf[slot]) {
			pkt = fas->f_readyf[slot]->cmd_pkt;
		} else if (fas_atest_disc == 4 &&
		    fas->f_readyf[slot] && fas->f_readyf[slot]->cmd_forw) {
			pkt = fas->f_readyf[slot]->cmd_forw->cmd_pkt;
		} else if (fas_atest_disc == 5 && fas->f_readyb[slot]) {
			pkt = fas->f_readyb[slot]->cmd_pkt;
		} else if ((fas_atest_disc == 6) && sp &&
		    (sp->cmd_slot == slot) &&
		    (fas->f_state == ACTS_DATA_DONE)) {
			pkt = sp->cmd_pkt;
		} else if (fas_atest_disc == 7) {
			if (fas_do_scsi_abort(&ap, NULL)) {
				if (fas_do_scsi_abort(&ap, NULL)) {
					if (fas_do_scsi_reset(&ap,
					    RESET_TARGET)) {
						fas_atest = 0;
					}
				}
			}
			return;
		} else {
			return;
		}

		fas_log(fas, CE_NOTE, "aborting pkt=0x%p state=%x\n",
		    (void *)pkt, (pkt != NULL? pkt->pkt_state : 0));
		if (fas_do_scsi_abort(&ap, pkt)) {
			fas_atest = 0;
		}
	}
}
#endif /* FAS_TEST */

/*
 * capability interface
 */
static int
fas_commoncap(struct scsi_address *ap, char *cap, int val,
    int tgtonly, int doset)
{
	struct fas *fas = ADDR2FAS(ap);
	int cidx;
	int target = ap->a_target;
	ushort_t tshift = (1<<target);
	ushort_t ntshift = ~tshift;
	int rval = FALSE;

	mutex_enter(FAS_MUTEX(fas));

	if (cap == (char *)0) {
		goto exit;
	}

	cidx = scsi_hba_lookup_capstr(cap);
	if (cidx == -1) {
		rval = UNDEFINED;
	} else if (doset) {
		/*
		 * we usually don't allow setting capabilities for
		 * other targets!
		 */
		if (!tgtonly) {
			goto exit;
		}
		switch (cidx) {
		case SCSI_CAP_DMA_MAX:
		case SCSI_CAP_MSG_OUT:
		case SCSI_CAP_PARITY:
		case SCSI_CAP_INITIATOR_ID:
		case SCSI_CAP_LINKED_CMDS:
		case SCSI_CAP_UNTAGGED_QING:
		case SCSI_CAP_RESET_NOTIFICATION:
			/*
			 * None of these are settable via
			 * the capability interface.
			 */
			break;

		case SCSI_CAP_DISCONNECT:
			if (val)
				fas->f_target_scsi_options[ap->a_target] |=
				    SCSI_OPTIONS_DR;
			else
				fas->f_target_scsi_options[ap->a_target] &=
				    ~SCSI_OPTIONS_DR;

			break;

		case SCSI_CAP_SYNCHRONOUS:
			if (val) {
				fas->f_force_async &= ~tshift;
			} else {
				fas->f_force_async |= tshift;
			}
			fas_force_renegotiation(fas, target);
			rval = TRUE;
			break;

		case SCSI_CAP_TAGGED_QING:
		{
			int slot = target * NLUNS_PER_TARGET | ap->a_lun;
			ushort_t old_notag = fas->f_notag;

			/* do not allow with active tgt */
			if (fas->f_tcmds[slot]) {
				break;
			}

			slot =	target * NLUNS_PER_TARGET | ap->a_lun;

			if (val) {
				if (fas->f_target_scsi_options[target] &
				    SCSI_OPTIONS_TAG) {
					IPRINTF1("target %d: TQ enabled\n",
					    target);
					fas->f_notag &= ntshift;
				} else {
					break;
				}
			} else {
				IPRINTF1("target %d: TQ disabled\n",
				    target);
				fas->f_notag |= tshift;
			}

			if (val && fas_alloc_active_slots(fas, slot,
			    KM_NOSLEEP)) {
				fas->f_notag = old_notag;
				break;
			}

			fas_set_all_lun_throttles(fas, slot, MAX_THROTTLE);

			fas_update_props(fas, target);
			rval = TRUE;
			break;
		}

		case SCSI_CAP_WIDE_XFER:
			if (val) {
				if (fas->f_target_scsi_options[target] &
				    SCSI_OPTIONS_WIDE) {
					fas->f_nowide &= ntshift;
					fas->f_force_narrow &= ~tshift;
				} else {
					break;
				}
			} else {
				fas->f_force_narrow |= tshift;
			}
			fas_force_renegotiation(fas, target);
			rval = TRUE;
			break;

		case SCSI_CAP_ARQ:
			if (val) {
				if (fas_create_arq_pkt(fas, ap)) {
					break;
				}
			} else {
				if (fas_delete_arq_pkt(fas, ap)) {
					break;
				}
			}
			rval = TRUE;
			break;

		case SCSI_CAP_QFULL_RETRIES:
			fas->f_qfull_retries[target] = (uchar_t)val;
			rval = TRUE;
			break;

		case SCSI_CAP_QFULL_RETRY_INTERVAL:
			fas->f_qfull_retry_interval[target] =
			    drv_usectohz(val * 1000);
			rval = TRUE;
			break;

		default:
			rval = UNDEFINED;
			break;
		}

	} else if (doset == 0) {
		int slot = target * NLUNS_PER_TARGET | ap->a_lun;

		switch (cidx) {
		case SCSI_CAP_DMA_MAX:
			/* very high limit because of multiple dma windows */
			rval = 1<<30;
			break;
		case SCSI_CAP_MSG_OUT:
			rval = TRUE;
			break;
		case SCSI_CAP_DISCONNECT:
			if (tgtonly &&
			    (fas->f_target_scsi_options[target] &
			    SCSI_OPTIONS_DR)) {
				rval = TRUE;
			}
			break;
		case SCSI_CAP_SYNCHRONOUS:
			if (tgtonly && fas->f_offset[target]) {
				rval = TRUE;
			}
			break;
		case SCSI_CAP_PARITY:
			rval = TRUE;
			break;
		case SCSI_CAP_INITIATOR_ID:
			rval = MY_ID(fas);
			break;
		case SCSI_CAP_TAGGED_QING:
			if (tgtonly && ((fas->f_notag & tshift) == 0)) {
				rval = TRUE;
			}
			break;
		case SCSI_CAP_WIDE_XFER:
			if ((tgtonly && (fas->f_nowide & tshift) == 0)) {
				rval = TRUE;
			}
			break;
		case SCSI_CAP_UNTAGGED_QING:
			rval = TRUE;
			break;
		case SCSI_CAP_ARQ:
			if (tgtonly && fas->f_arq_pkt[slot]) {
				rval = TRUE;
			}
			break;
		case SCSI_CAP_LINKED_CMDS:
			break;
		case SCSI_CAP_RESET_NOTIFICATION:
			rval = TRUE;
			break;
		case SCSI_CAP_QFULL_RETRIES:
			rval = fas->f_qfull_retries[target];
			break;
		case SCSI_CAP_QFULL_RETRY_INTERVAL:
			rval = drv_hztousec(
			    fas->f_qfull_retry_interval[target]) /
			    1000;
			break;

		default:
			rval = UNDEFINED;
			break;
		}
	}
exit:
	if (val && tgtonly) {
		fas_update_props(fas, target);
	}
	fas_check_waitQ_and_mutex_exit(fas);

	if (doset) {
		IPRINTF6(
	    "fas_commoncap:tgt=%x,cap=%s,tgtonly=%x,doset=%x,val=%x,rval=%x\n",
		    target, cap, tgtonly, doset, val, rval);
	}
	return (rval);
}

/*
 * property management
 * fas_update_props:
 * create/update sync/wide/TQ/scsi-options properties for this target
 */
static void
fas_update_props(struct fas *fas, int tgt)
{
	char	property[32];
	uint_t	xfer_speed = 0;
	uint_t	xfer_rate = 0;
	int	wide_enabled, tq_enabled;
	uint_t	regval = fas->f_sync_period[tgt];
	int	offset = fas->f_offset[tgt];

	wide_enabled = ((fas->f_nowide & (1<<tgt)) == 0);
	if (offset && regval) {
		xfer_speed =
		    FAS_SYNC_KBPS((regval * fas->f_clock_cycle) / 1000);
		xfer_rate = ((wide_enabled)? 2 : 1) * xfer_speed;
	}
	(void) sprintf(property, "target%x-sync-speed", tgt);
	fas_update_this_prop(fas, property, xfer_rate);

	(void) sprintf(property, "target%x-wide", tgt);
	fas_update_this_prop(fas, property, wide_enabled);

	(void) sprintf(property, "target%x-TQ", tgt);
	tq_enabled = ((fas->f_notag & (1<<tgt))? 0 : 1);
	fas_update_this_prop(fas, property, tq_enabled);

}

static void
fas_update_this_prop(struct fas *fas, char *property, int value)
{
	dev_info_t *dip = fas->f_dev;

	IPRINTF2("update prop: %s value=%x\n", property, value);
	ASSERT(mutex_owned(FAS_MUTEX(fas)));
	/*
	 * We cannot hold any mutex at this point because the call to
	 * ddi_prop_update_int() may block.
	 */
	mutex_exit(FAS_MUTEX(fas));
	if (ddi_prop_update_int(DDI_DEV_T_NONE, dip,
	    property, value) != DDI_PROP_SUCCESS)	{
		IPRINTF1("cannot modify/create %s property\n",	property);
	}
	mutex_enter(FAS_MUTEX(fas));
}

/*
 * allocate active slots array, size is dependent on whether tagQ enabled
 */
static int
fas_alloc_active_slots(struct fas *fas, int slot, int flag)
{
	int target = slot / NLUNS_PER_TARGET;
	struct f_slots *old_active = fas->f_active[slot];
	struct f_slots *new_active;
	ushort_t size;
	int rval = -1;

	if (fas->f_tcmds[slot]) {
		IPRINTF("cannot change size of active slots array\n");
		return (rval);
	}

	size = ((NOTAG(target)) ? FAS_F_SLOT_SIZE : FAS_F_SLOTS_SIZE_TQ);
	EPRINTF4(
	"fas_alloc_active_slots: target=%x size=%x, old=0x%p, oldsize=%x\n",
	    target, size, (void *)old_active,
	    ((old_active == NULL) ? -1 : old_active->f_size));

	new_active = kmem_zalloc(size, flag);
	if (new_active == NULL) {
		IPRINTF("new active alloc failed\n");
	} else {
		fas->f_active[slot] = new_active;
		fas->f_active[slot]->f_n_slots = (NOTAG(target) ? 1 : NTAGS);
		fas->f_active[slot]->f_size = size;
		/*
		 * reserve tag 0 for non-tagged cmds to tagged targets
		 */
		if (TAGGED(target)) {
			fas->f_active[slot]->f_tags = 1;
		}
		if (old_active) {
			kmem_free((caddr_t)old_active, old_active->f_size);
		}
		rval = 0;
	}
	return (rval);
}

/*
 * Error logging, printing, and debug print routines
 */
static char *fas_label = "fas";

/*PRINTFLIKE3*/
static void
fas_log(struct fas *fas, int level, const char *fmt, ...)
{
	dev_info_t *dev;
	va_list ap;

	if (fas) {
		dev = fas->f_dev;
	} else {
		dev = 0;
	}

	mutex_enter(&fas_log_mutex);

	va_start(ap, fmt);
	(void) vsprintf(fas_log_buf, fmt, ap);
	va_end(ap);

	if (level == CE_CONT) {
		scsi_log(dev, fas_label, level, "%s\n", fas_log_buf);
	} else {
		scsi_log(dev, fas_label, level, "%s", fas_log_buf);
	}

	mutex_exit(&fas_log_mutex);
}

/*PRINTFLIKE2*/
static void
fas_printf(struct fas *fas, const char *fmt, ...)
{
	dev_info_t *dev = 0;
	va_list ap;
	int level = CE_CONT;

	mutex_enter(&fas_log_mutex);

	va_start(ap, fmt);
	(void) vsprintf(fas_log_buf, fmt, ap);
	va_end(ap);

	if (fas) {
		dev = fas->f_dev;
		level = CE_NOTE;
		scsi_log(dev, fas_label, level, "%s", fas_log_buf);
	} else {
		scsi_log(dev, fas_label, level, "%s\n", fas_log_buf);
	}

	mutex_exit(&fas_log_mutex);
}

#ifdef FASDEBUG
/*PRINTFLIKE2*/
void
fas_dprintf(struct fas *fas, const char *fmt, ...)
{
	dev_info_t *dev = 0;
	va_list ap;

	if (fas) {
		dev = fas->f_dev;
	}

	mutex_enter(&fas_log_mutex);

	va_start(ap, fmt);
	(void) vsprintf(fas_log_buf, fmt, ap);
	va_end(ap);

	scsi_log(dev, fas_label, SCSI_DEBUG, "%s", fas_log_buf);

	mutex_exit(&fas_log_mutex);
}
#endif


static void
fas_printstate(struct fas *fas, char *msg)
{
	volatile struct fasreg *fasreg = fas->f_reg;
	volatile struct dma *dmar = fas->f_dma;
	uint_t csr = fas_dma_reg_read(fas, &dmar->dma_csr);
	uint_t count = fas_dma_reg_read(fas, &dmar->dma_count);
	uint_t addr = fas_dma_reg_read(fas, &dmar->dma_addr);
	uint_t test = fas_dma_reg_read(fas, &dmar->dma_test);
	uint_t fas_cnt;

	fas_log(fas, CE_WARN, "%s: current fas state:", msg);
	fas_printf(NULL, "Latched stat=0x%b intr=0x%b",
	    fas->f_stat, FAS_STAT_BITS, fas->f_intr, FAS_INT_BITS);
	fas_printf(NULL, "last msgout: %s, last msgin: %s",
	    scsi_mname(fas->f_last_msgout), scsi_mname(fas->f_last_msgin));
	fas_printf(NULL, "DMA csr=0x%b", csr, dma_bits);
	fas_printf(NULL,
	    "addr=%x dmacnt=%x test=%x last=%x last_cnt=%x",
	    addr, count, test, fas->f_lastdma, fas->f_lastcount);

	GET_FAS_COUNT(fasreg, fas_cnt);
	fas_printf(NULL, "fas state:");
	fas_printf(NULL, "\tcount(32)=%x cmd=%x stat=%x stat2=%x intr=%x",
	    fas_cnt, fasreg->fas_cmd, fasreg->fas_stat, fasreg->fas_stat2,
	    fasreg->fas_intr);
	fas_printf(NULL,
	"\tstep=%x fifoflag=%x conf=%x test=%x conf2=%x conf3=%x",
	    fasreg->fas_step, fasreg->fas_fifo_flag, fasreg->fas_conf,
	    fasreg->fas_test, fasreg->fas_conf2, fasreg->fas_conf3);

	if (fas->f_current_sp) {
		fas_dump_cmd(fas, fas->f_current_sp);
	}
}

/*
 * dump all we know about a cmd
 */
static void
fas_dump_cmd(struct fas *fas, struct fas_cmd *sp)
{
	int i;
	uchar_t *cp = (uchar_t *)sp->cmd_pkt->pkt_cdbp;
	auto char buf[128];

	buf[0] = '\0';
	fas_printf(NULL, "Cmd dump for Target %d Lun %d:",
	    Tgt(sp), Lun(sp));
	(void) sprintf(&buf[0], " cdb=[");
	for (i = 0; i < (int)sp->cmd_actual_cdblen; i++) {
		(void) sprintf(&buf[strlen(buf)], " 0x%x", *cp++);
	}
	(void) sprintf(&buf[strlen(buf)], " ]");
	fas_printf(NULL, buf);
	fas_printf(NULL, "State=%s Last State=%s",
	    fas_state_name(fas->f_state), fas_state_name(fas->f_laststate));
	fas_printf(NULL,
	    "pkt_state=0x%b pkt_flags=0x%x pkt_statistics=0x%x",
	    sp->cmd_pkt->pkt_state, scsi_state_bits, sp->cmd_pkt_flags,
	    sp->cmd_pkt->pkt_statistics);
	if (sp->cmd_pkt->pkt_state & STATE_GOT_STATUS) {
		fas_printf(NULL, "Status=0x%x\n", sp->cmd_pkt->pkt_scbp[0]);
	}
}

/*ARGSUSED*/
static void
fas_short_dump_cmd(struct fas *fas, struct fas_cmd *sp)
{
	int i;
	uchar_t *cp = (uchar_t *)sp->cmd_pkt->pkt_cdbp;
	auto char buf[128];

	buf[0] = '\0';
	(void) sprintf(&buf[0], "?%d.%d: cdb=[", Tgt(sp), Lun(sp));
	for (i = 0; i < (int)sp->cmd_actual_cdblen; i++) {
		(void) sprintf(&buf[strlen(buf)], " 0x%x", *cp++);
	}
	(void) sprintf(&buf[strlen(buf)], " ]");
	fas_printf(NULL, buf);
}

/*
 * state decoding for error messages
 */
static char *
fas_state_name(ushort_t state)
{
	if (state == STATE_FREE) {
		return ("FREE");
	} else if (state & STATE_SELECTING) {
		if (state == STATE_SELECT_NORMAL)
			return ("SELECT");
		else if (state == STATE_SELECT_N_STOP)
			return ("SEL&STOP");
		else if (state == STATE_SELECT_N_SENDMSG)
			return ("SELECT_SNDMSG");
		else
			return ("SEL_NO_ATN");
	} else {
		static struct {
			char *sname;
			char state;
		} names[] = {
			"CMD_START",		ACTS_CMD_START,
			"CMD_DONE",		ACTS_CMD_DONE,
			"MSG_OUT",		ACTS_MSG_OUT,
			"MSG_OUT_DONE", 	ACTS_MSG_OUT_DONE,
			"MSG_IN",		ACTS_MSG_IN,
			"MSG_IN_MORE",		ACTS_MSG_IN_MORE,
			"MSG_IN_DONE",		ACTS_MSG_IN_DONE,
			"CLEARING",		ACTS_CLEARING,
			"DATA", 		ACTS_DATA,
			"DATA_DONE",		ACTS_DATA_DONE,
			"CMD_CMPLT",		ACTS_C_CMPLT,
			"UNKNOWN",		ACTS_UNKNOWN,
			"RESEL",		ACTS_RESEL,
			"ENDVEC",		ACTS_ENDVEC,
			"RESET",		ACTS_RESET,
			"ABORTING",		ACTS_ABORTING,
			"FROZEN",		ACTS_FROZEN,
			0
		};
		int i;
		for (i = 0; names[i].sname; i++) {
			if (names[i].state == state)
				return (names[i].sname);
		}
	}
	return ("<BAD>");
}