xref: /freebsd/sys/dev/mpt/mpt_pci.c (revision 444dd2b6692b3ae681d7faa78c5b39463ccb5936)

/*-
 * PCI specific probe and attach routines for LSI Fusion Adapters
 * FreeBSD Version.
 *
 * Copyright (c) 2000, 2001 by Greg Ansley
 * Partially derived from Matt Jacob's ISP driver.
 * Copyright (c) 1997, 1998, 1999, 2000, 2001, 2002 by Matthew Jacob
 * Feral Software
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice immediately at the beginning of the file, without modification,
 *    this list of conditions, and the following disclaimer.
 * 2. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
/*
 * Copyright (c) 2004, Avid Technology, Inc. and its contributors.
 * Copyright (c) 2005, WHEEL Sp. z o.o.
 * Copyright (c) 2004, 2005 Justin T. Gibbs
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon including
 *    a substantially similar Disclaimer requirement for further binary
 *    redistribution.
 * 3. Neither the names of the above listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF THE COPYRIGHT
 * OWNER OR CONTRIBUTOR IS ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <dev/mpt/mpt.h>
#include <dev/mpt/mpt_cam.h>
#include <dev/mpt/mpt_raid.h>


#ifndef	PCI_VENDOR_LSI
#define	PCI_VENDOR_LSI			0x1000
#endif

#ifndef	PCI_PRODUCT_LSI_FC909
#define	PCI_PRODUCT_LSI_FC909		0x0620
#endif

#ifndef	PCI_PRODUCT_LSI_FC909A
#define	PCI_PRODUCT_LSI_FC909A		0x0621
#endif

#ifndef	PCI_PRODUCT_LSI_FC919
#define	PCI_PRODUCT_LSI_FC919		0x0624
#endif

#ifndef	PCI_PRODUCT_LSI_FC929
#define	PCI_PRODUCT_LSI_FC929		0x0622
#endif

#ifndef	PCI_PRODUCT_LSI_FC929X
#define	PCI_PRODUCT_LSI_FC929X		0x0626
#endif

#ifndef	PCI_PRODUCT_LSI_1030
#define	PCI_PRODUCT_LSI_1030		0x0030
#endif

#ifndef	PCI_PRODUCT_LSI_SAS1064
#define PCI_PRODUCT_LSI_SAS1064		0x0050
#endif

#ifndef PCI_PRODUCT_LSI_SAS1064A
#define PCI_PRODUCT_LSI_SAS1064A	0x005C
#endif

#ifndef PCI_PRODUCT_LSI_SAS1064E
#define PCI_PRODUCT_LSI_SAS1064E	0x0056
#endif

#ifndef PCI_PRODUCT_LSI_SAS1066
#define PCI_PRODUCT_LSI_SAS1066		0x005E
#endif

#ifndef PCI_PRODUCT_LSI_SAS1066E
#define PCI_PRODUCT_LSI_SAS1066E	0x005A
#endif

#ifndef PCI_PRODUCT_LSI_SAS1068
#define PCI_PRODUCT_LSI_SAS1068		0x0054
#endif

#ifndef PCI_PRODUCT_LSI_SAS1068E
#define PCI_PRODUCT_LSI_SAS1068E	0x0058
#endif

#ifndef PCI_PRODUCT_LSI_SAS1078
#define PCI_PRODUCT_LSI_SAS1078		0x0060
#endif

#ifndef	PCIM_CMD_SERRESPEN
#define	PCIM_CMD_SERRESPEN	0x0100
#endif


#define	MPT_IO_BAR	0
#define	MPT_MEM_BAR	1

static int mpt_pci_probe(device_t);
static int mpt_pci_attach(device_t);
static void mpt_free_bus_resources(struct mpt_softc *mpt);
static int mpt_pci_detach(device_t);
static int mpt_pci_shutdown(device_t);
static int mpt_dma_mem_alloc(struct mpt_softc *mpt);
static void mpt_dma_mem_free(struct mpt_softc *mpt);
static void mpt_read_config_regs(struct mpt_softc *mpt);
static void mpt_pci_intr(void *);

static device_method_t mpt_methods[] = {
	/* Device interface */
	DEVMETHOD(device_probe,		mpt_pci_probe),
	DEVMETHOD(device_attach,	mpt_pci_attach),
	DEVMETHOD(device_detach,	mpt_pci_detach),
	DEVMETHOD(device_shutdown,	mpt_pci_shutdown),
	{ 0, 0 }
};

static driver_t mpt_driver = {
	"mpt", mpt_methods, sizeof(struct mpt_softc)
};
static devclass_t mpt_devclass;
DRIVER_MODULE(mpt, pci, mpt_driver, mpt_devclass, 0, 0);
MODULE_VERSION(mpt, 1);

static int
mpt_pci_probe(device_t dev)
{
	char *desc;

	if (pci_get_vendor(dev) != PCI_VENDOR_LSI)
		return (ENXIO);

	switch ((pci_get_device(dev) & ~1)) {
	case PCI_PRODUCT_LSI_FC909:
		desc = "LSILogic FC909 FC Adapter";
		break;
	case PCI_PRODUCT_LSI_FC909A:
		desc = "LSILogic FC909A FC Adapter";
		break;
	case PCI_PRODUCT_LSI_FC919:
		desc = "LSILogic FC919 FC Adapter";
		break;
	case PCI_PRODUCT_LSI_FC929:
		desc = "LSILogic FC929 FC Adapter";
		break;
	case PCI_PRODUCT_LSI_FC929X:
		desc = "LSILogic FC929X FC Adapter";
		break;
	case PCI_PRODUCT_LSI_1030:
		desc = "LSILogic 1030 Ultra4 Adapter";
		break;
	case PCI_PRODUCT_LSI_SAS1064:
	case PCI_PRODUCT_LSI_SAS1064A:
	case PCI_PRODUCT_LSI_SAS1064E:
	case PCI_PRODUCT_LSI_SAS1066:
	case PCI_PRODUCT_LSI_SAS1066E:
	case PCI_PRODUCT_LSI_SAS1068:
	case PCI_PRODUCT_LSI_SAS1068E:
	case PCI_PRODUCT_LSI_SAS1078:
		desc = "LSILogic SAS Adapter";
		break;
	default:
		return (ENXIO);
	}

	device_set_desc(dev, desc);
	return (0);
}

#ifdef	RELENG_4
static void
mpt_set_options(struct mpt_softc *mpt)
{
	int bitmap;

	bitmap = 0;
	if (getenv_int("mpt_disable", &bitmap)) {
		if (bitmap & (1 << mpt->unit)) {
			mpt->disabled = 1;
		}
	}

	bitmap = 0;
	if (getenv_int("mpt_debug", &bitmap)) {
		if (bitmap & (1 << mpt->unit)) {
			mpt->verbose = MPT_PRT_DEBUG;
		}
	}

}
#else
static void
mpt_set_options(struct mpt_softc *mpt)
{
	int tval;

	tval = 0;
	if (resource_int_value(device_get_name(mpt->dev),
	    device_get_unit(mpt->dev), "disable", &tval) == 0 && tval != 0) {
		mpt->disabled = 1;
	}
	tval = 0;
	if (resource_int_value(device_get_name(mpt->dev),
	    device_get_unit(mpt->dev), "debug", &tval) == 0 && tval != 0) {
		mpt->verbose += tval;
	}
}
#endif


static void
mpt_link_peer(struct mpt_softc *mpt)
{
	struct mpt_softc *mpt2;

	if (mpt->unit == 0)
		return;

	/*
	 * XXX: depends on probe order
	 */
	mpt2 = (struct mpt_softc *)devclass_get_softc(mpt_devclass,mpt->unit-1);

	if (mpt2 == NULL) {
		return;
	}
	if (pci_get_vendor(mpt2->dev) != pci_get_vendor(mpt->dev)) {
		return;
	}
	if (pci_get_device(mpt2->dev) != pci_get_device(mpt->dev)) {
		return;
	}
	mpt->mpt2 = mpt2;
	mpt2->mpt2 = mpt;
	if (mpt->verbose >= MPT_PRT_DEBUG) {
		mpt_prt(mpt, "linking with peer (mpt%d)\n",
		    device_get_unit(mpt2->dev));
	}
}


static int
mpt_pci_attach(device_t dev)
{
	struct mpt_softc *mpt;
	int		  iqd;
	uint32_t	  data, cmd;

	/* Allocate the softc structure */
	mpt  = (struct mpt_softc*)device_get_softc(dev);
	if (mpt == NULL) {
		device_printf(dev, "cannot allocate softc\n");
		return (ENOMEM);
	}
	bzero(mpt, sizeof(struct mpt_softc));
	switch ((pci_get_device(dev) & ~1)) {
	case PCI_PRODUCT_LSI_FC909:
	case PCI_PRODUCT_LSI_FC909A:
	case PCI_PRODUCT_LSI_FC919:
	case PCI_PRODUCT_LSI_FC929:
		mpt->is_fc = 1;
		break;
	case PCI_PRODUCT_LSI_SAS1064:
	case PCI_PRODUCT_LSI_SAS1064A:
	case PCI_PRODUCT_LSI_SAS1064E:
	case PCI_PRODUCT_LSI_SAS1066:
	case PCI_PRODUCT_LSI_SAS1066E:
	case PCI_PRODUCT_LSI_SAS1068:
	case PCI_PRODUCT_LSI_SAS1068E:
	case PCI_PRODUCT_LSI_SAS1078:
		mpt->is_sas = 1;
		break;
	default:
		break;
	}
	mpt->dev = dev;
	mpt->unit = device_get_unit(dev);
	mpt->raid_resync_rate = MPT_RAID_RESYNC_RATE_DEFAULT;
	mpt->raid_mwce_setting = MPT_RAID_MWCE_DEFAULT;
	mpt->raid_queue_depth = MPT_RAID_QUEUE_DEPTH_DEFAULT;
	mpt->verbose = MPT_PRT_NONE;
	mpt_set_options(mpt);
	if (mpt->verbose == MPT_PRT_NONE) {
		mpt->verbose = MPT_PRT_WARN;
		/* Print INFO level (if any) if bootverbose is set */
		mpt->verbose += (bootverbose != 0)? 1 : 0;
	}
	/* Make sure memory access decoders are enabled */
	cmd = pci_read_config(dev, PCIR_COMMAND, 2);
	if ((cmd & PCIM_CMD_MEMEN) == 0) {
		device_printf(dev, "Memory accesses disabled");
		goto bad;
	}

	/*
	 * Make sure that SERR, PERR, WRITE INVALIDATE and BUSMASTER are set.
	 */
	cmd |=
	    PCIM_CMD_SERRESPEN | PCIM_CMD_PERRESPEN |
	    PCIM_CMD_BUSMASTEREN | PCIM_CMD_MWRICEN;
	pci_write_config(dev, PCIR_COMMAND, cmd, 2);

	/*
	 * Make sure we've disabled the ROM.
	 */
	data = pci_read_config(dev, PCIR_BIOS, 4);
	data &= ~1;
	pci_write_config(dev, PCIR_BIOS, data, 4);

	/*
	 * Is this part a dual?
	 * If so, link with our partner (around yet)
	 */
	if ((pci_get_device(dev) & ~1) == PCI_PRODUCT_LSI_FC929 ||
	    (pci_get_device(dev) & ~1) == PCI_PRODUCT_LSI_1030) {
		mpt_link_peer(mpt);
	}

	/*
	 * Set up register access.  PIO mode is required for
	 * certain reset operations (but must be disabled for
	 * some cards otherwise).
	 */
	mpt->pci_pio_rid = PCIR_BAR(MPT_IO_BAR);
	mpt->pci_pio_reg = bus_alloc_resource(dev, SYS_RES_IOPORT,
			    &mpt->pci_pio_rid, 0, ~0, 0, RF_ACTIVE);
	if (mpt->pci_pio_reg == NULL) {
		device_printf(dev, "unable to map registers in PIO mode\n");
		goto bad;
	}
	mpt->pci_pio_st = rman_get_bustag(mpt->pci_pio_reg);
	mpt->pci_pio_sh = rman_get_bushandle(mpt->pci_pio_reg);

	/* Allocate kernel virtual memory for the 9x9's Mem0 region */
	mpt->pci_mem_rid = PCIR_BAR(MPT_MEM_BAR);
	mpt->pci_reg = bus_alloc_resource(dev, SYS_RES_MEMORY,
			&mpt->pci_mem_rid, 0, ~0, 0, RF_ACTIVE);
	if (mpt->pci_reg == NULL) {
		device_printf(dev, "Unable to memory map registers.\n");
		if (mpt->is_sas) {
			device_printf(dev, "Giving Up.\n");
			goto bad;
		}
		device_printf(dev, "Falling back to PIO mode.\n");
		mpt->pci_st = mpt->pci_pio_st;
		mpt->pci_sh = mpt->pci_pio_sh;
	} else {
		mpt->pci_st = rman_get_bustag(mpt->pci_reg);
		mpt->pci_sh = rman_get_bushandle(mpt->pci_reg);
	}

	/* Get a handle to the interrupt */
	iqd = 0;
#if __FreeBSD_version < 500000
	mpt->pci_irq = bus_alloc_resource(dev, SYS_RES_IRQ, &iqd, 0, ~0, 1,
	    RF_ACTIVE | RF_SHAREABLE);
#else
	mpt->pci_irq = bus_alloc_resource_any(dev, SYS_RES_IRQ, &iqd,
	    RF_ACTIVE | RF_SHAREABLE);
#endif
	if (mpt->pci_irq == NULL) {
		device_printf(dev, "could not allocate interrupt\n");
		goto bad;
	}

	MPT_LOCK_SETUP(mpt);

	/* Disable interrupts at the part */
	mpt_disable_ints(mpt);

	/* Register the interrupt handler */
	if (bus_setup_intr(dev, mpt->pci_irq, MPT_IFLAGS, mpt_pci_intr,
	    mpt, &mpt->ih)) {
		device_printf(dev, "could not setup interrupt\n");
		goto bad;
	}

	/* Allocate dma memory */
/* XXX JGibbs -Should really be done based on IOCFacts. */
	if (mpt_dma_mem_alloc(mpt)) {
		device_printf(dev, "Could not allocate DMA memory\n");
		goto bad;
	}

	/*
	 * Save the PCI config register values
 	 *
	 * Hard resets are known to screw up the BAR for diagnostic
	 * memory accesses (Mem1).
	 *
	 * Using Mem1 is known to make the chip stop responding to
	 * configuration space transfers, so we need to save it now
	 */

	mpt_read_config_regs(mpt);

	/*
	 * Disable PIO until we need it
	 */
	pci_disable_io(dev, SYS_RES_IOPORT);

	/* Initialize the hardware */
	if (mpt->disabled == 0) {

		MPT_LOCK(mpt);
		if (mpt_attach(mpt) != 0) {
			MPT_UNLOCK(mpt);
			goto bad;
		}
	}

	return (0);

bad:
	mpt_dma_mem_free(mpt);
	mpt_free_bus_resources(mpt);

	/*
	 * but return zero to preserve unit numbering
	 */
	return (0);
}

/*
 * Free bus resources
 */
static void
mpt_free_bus_resources(struct mpt_softc *mpt)
{
	if (mpt->ih) {
		bus_teardown_intr(mpt->dev, mpt->pci_irq, mpt->ih);
		mpt->ih = 0;
	}

	if (mpt->pci_irq) {
		bus_release_resource(mpt->dev, SYS_RES_IRQ, 0, mpt->pci_irq);
		mpt->pci_irq = 0;
	}

	if (mpt->pci_pio_reg) {
		bus_release_resource(mpt->dev, SYS_RES_IOPORT, mpt->pci_pio_rid,
			mpt->pci_pio_reg);
		mpt->pci_pio_reg = 0;
	}
	if (mpt->pci_reg) {
		bus_release_resource(mpt->dev, SYS_RES_MEMORY, mpt->pci_mem_rid,
			mpt->pci_reg);
		mpt->pci_reg = 0;
	}
	MPT_LOCK_DESTROY(mpt);
}


/*
 * Disconnect ourselves from the system.
 */
static int
mpt_pci_detach(device_t dev)
{
	struct mpt_softc *mpt;

	mpt  = (struct mpt_softc*)device_get_softc(dev);
	mpt_prt(mpt, "mpt_detach\n");

	if (mpt) {
		mpt_disable_ints(mpt);
		mpt_detach(mpt);
		mpt_reset(mpt, /*reinit*/FALSE);
		mpt_dma_mem_free(mpt);
		mpt_free_bus_resources(mpt);
		if (mpt->raid_volumes != NULL
		 && mpt->ioc_page2 != NULL) {
			int i;

			for (i = 0; i < mpt->ioc_page2->MaxVolumes; i++) {
				struct mpt_raid_volume *mpt_vol;

				mpt_vol = &mpt->raid_volumes[i];
				if (mpt_vol->config_page)
					free(mpt_vol->config_page, M_DEVBUF);
			}
		}
		if (mpt->ioc_page2 != NULL)
			free(mpt->ioc_page2, M_DEVBUF);
		if (mpt->ioc_page3 != NULL)
			free(mpt->ioc_page3, M_DEVBUF);
		if (mpt->raid_volumes != NULL)
			free(mpt->raid_volumes, M_DEVBUF);
		if (mpt->raid_disks != NULL)
			free(mpt->raid_disks, M_DEVBUF);
		if (mpt->eh != NULL)
                        EVENTHANDLER_DEREGISTER(shutdown_final, mpt->eh);
	}
	return(0);
}


/*
 * Disable the hardware
 * XXX - Called too early by New Bus!!!  ???
 */
static int
mpt_pci_shutdown(device_t dev)
{
	struct mpt_softc *mpt;

	mpt = (struct mpt_softc *)device_get_softc(dev);
	if (mpt)
		return (mpt_shutdown(mpt));
	return(0);
}

static int
mpt_dma_mem_alloc(struct mpt_softc *mpt)
{
	int i, error, nsegs;
	uint8_t *vptr;
	uint32_t pptr, end;
	size_t len;
	struct mpt_map_info mi;
	device_t dev = mpt->dev;

	/* Check if we alreay have allocated the reply memory */
	if (mpt->reply_phys != 0) {
		return 0;
	}

	len = sizeof (request_t) * MPT_MAX_REQUESTS(mpt);
#ifdef	RELENG_4
	mpt->request_pool = (request_t *)malloc(len, M_DEVBUF, M_WAITOK);
	if (mpt->request_pool == NULL) {
		device_printf(dev, "cannot allocate request pool\n");
		return (1);
	}
	bzero(mpt->request_pool, len);
#else
	mpt->request_pool = (request_t *)malloc(len, M_DEVBUF, M_WAITOK|M_ZERO);
	if (mpt->request_pool == NULL) {
		device_printf(dev, "cannot allocate request pool\n");
		return (1);
	}
#endif

	/*
	 * Create a parent dma tag for this device.
	 *
	 * Align at byte boundaries, limit to 32-bit addressing for
	 * request/reply queues.
	 */
	if (mpt_dma_tag_create(mpt, /*parent*/NULL, /*alignment*/1,
	    /*boundary*/0, /*lowaddr*/BUS_SPACE_MAXADDR,
	    /*highaddr*/BUS_SPACE_MAXADDR, /*filter*/NULL, /*filterarg*/NULL,
	    /*maxsize*/BUS_SPACE_MAXSIZE_32BIT,
	    /*nsegments*/BUS_SPACE_MAXSIZE_32BIT,
	    /*maxsegsz*/BUS_SPACE_UNRESTRICTED, /*flags*/0,
	    &mpt->parent_dmat) != 0) {
		device_printf(dev, "cannot create parent dma tag\n");
		return (1);
	}

	/* Create a child tag for reply buffers */
	if (mpt_dma_tag_create(mpt, mpt->parent_dmat, 2 * PAGE_SIZE,
	    0, BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR,
	    NULL, NULL, 2 * PAGE_SIZE, 1, BUS_SPACE_MAXSIZE_32BIT, 0,
	    &mpt->reply_dmat) != 0) {
		device_printf(dev, "cannot create a dma tag for replies\n");
		return (1);
	}

	/* Allocate some DMA accessable memory for replies */
	if (bus_dmamem_alloc(mpt->reply_dmat, (void **)&mpt->reply,
	    BUS_DMA_NOWAIT, &mpt->reply_dmap) != 0) {
		device_printf(dev,
		    "cannot allocate %lu bytes of reply memory\n",
		    (u_long) (2 * PAGE_SIZE));
		return (1);
	}

	mi.mpt = mpt;
	mi.error = 0;

	/* Load and lock it into "bus space" */
	bus_dmamap_load(mpt->reply_dmat, mpt->reply_dmap, mpt->reply,
	    2 * PAGE_SIZE, mpt_map_rquest, &mi, 0);

	if (mi.error) {
		device_printf(dev,
		    "error %d loading dma map for DMA reply queue\n", mi.error);
		return (1);
	}
	mpt->reply_phys = mi.phys;

	/* Create a child tag for data buffers */

	/*
	 * XXX: we should say that nsegs is 'unrestricted, but that
	 * XXX: tickles a horrible bug in the busdma code. Instead,
	 * XXX: we'll derive a reasonable segment limit from MAXPHYS
	 */
	nsegs = (MAXPHYS / PAGE_SIZE) + 1;
	if (mpt_dma_tag_create(mpt, mpt->parent_dmat, 1,
	    0, BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR,
	    NULL, NULL, MAXBSIZE, nsegs, BUS_SPACE_MAXSIZE_32BIT, 0,
	    &mpt->buffer_dmat) != 0) {
		device_printf(dev,
		    "cannot create a dma tag for data buffers\n");
		return (1);
	}

	/* Create a child tag for request buffers */
	if (mpt_dma_tag_create(mpt, mpt->parent_dmat, PAGE_SIZE,
	    0, BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR,
	    NULL, NULL, MPT_REQ_MEM_SIZE(mpt), 1, BUS_SPACE_MAXSIZE_32BIT, 0,
	    &mpt->request_dmat) != 0) {
		device_printf(dev, "cannot create a dma tag for requests\n");
		return (1);
	}

	/* Allocate some DMA accessable memory for requests */
	if (bus_dmamem_alloc(mpt->request_dmat, (void **)&mpt->request,
	    BUS_DMA_NOWAIT, &mpt->request_dmap) != 0) {
		device_printf(dev,
		    "cannot allocate %d bytes of request memory\n",
		    MPT_REQ_MEM_SIZE(mpt));
		return (1);
	}

	mi.mpt = mpt;
	mi.error = 0;

	/* Load and lock it into "bus space" */
        bus_dmamap_load(mpt->request_dmat, mpt->request_dmap, mpt->request,
	    MPT_REQ_MEM_SIZE(mpt), mpt_map_rquest, &mi, 0);

	if (mi.error) {
		device_printf(dev,
		    "error %d loading dma map for DMA request queue\n",
		    mi.error);
		return (1);
	}
	mpt->request_phys = mi.phys;

	i = 0;
	pptr =  mpt->request_phys;
	vptr =  mpt->request;
	end = pptr + MPT_REQ_MEM_SIZE(mpt);
	while(pptr < end) {
		request_t *req = &mpt->request_pool[i];
		req->index = i++;

		/* Store location of Request Data */
		req->req_pbuf = pptr;
		req->req_vbuf = vptr;

		pptr += MPT_REQUEST_AREA;
		vptr += MPT_REQUEST_AREA;

		req->sense_pbuf = (pptr - MPT_SENSE_SIZE);
		req->sense_vbuf = (vptr - MPT_SENSE_SIZE);

		error = bus_dmamap_create(mpt->buffer_dmat, 0, &req->dmap);
		if (error) {
			device_printf(dev,
			     "error %d creating per-cmd DMA maps\n", error);
			return (1);
		}
	}
	return (0);
}



/* Deallocate memory that was allocated by mpt_dma_mem_alloc
 */
static void
mpt_dma_mem_free(struct mpt_softc *mpt)
{
	int i;

        /* Make sure we aren't double destroying */
        if (mpt->reply_dmat == 0) {
		if (mpt->verbose >= MPT_PRT_DEBUG)
			device_printf(mpt->dev,"Already released dma memory\n");
		return;
        }

	for (i = 0; i < MPT_MAX_REQUESTS(mpt); i++) {
		bus_dmamap_destroy(mpt->buffer_dmat, mpt->request_pool[i].dmap);
	}
	bus_dmamap_unload(mpt->request_dmat, mpt->request_dmap);
	bus_dmamem_free(mpt->request_dmat, mpt->request, mpt->request_dmap);
	bus_dma_tag_destroy(mpt->request_dmat);
	bus_dma_tag_destroy(mpt->buffer_dmat);
	bus_dmamap_unload(mpt->reply_dmat, mpt->reply_dmap);
	bus_dmamem_free(mpt->reply_dmat, mpt->reply, mpt->reply_dmap);
	bus_dma_tag_destroy(mpt->reply_dmat);
	bus_dma_tag_destroy(mpt->parent_dmat);
	mpt->reply_dmat = 0;
	free(mpt->request_pool, M_DEVBUF);
	mpt->request_pool = 0;

}



/* Reads modifiable (via PCI transactions) config registers */
static void
mpt_read_config_regs(struct mpt_softc *mpt)
{
	mpt->pci_cfg.Command = pci_read_config(mpt->dev, PCIR_COMMAND, 2);
	mpt->pci_cfg.LatencyTimer_LineSize =
	    pci_read_config(mpt->dev, PCIR_CACHELNSZ, 2);
	mpt->pci_cfg.IO_BAR = pci_read_config(mpt->dev, PCIR_BAR(0), 4);
	mpt->pci_cfg.Mem0_BAR[0] = pci_read_config(mpt->dev, PCIR_BAR(1), 4);
	mpt->pci_cfg.Mem0_BAR[1] = pci_read_config(mpt->dev, PCIR_BAR(2), 4);
	mpt->pci_cfg.Mem1_BAR[0] = pci_read_config(mpt->dev, PCIR_BAR(3), 4);
	mpt->pci_cfg.Mem1_BAR[1] = pci_read_config(mpt->dev, PCIR_BAR(4), 4);
	mpt->pci_cfg.ROM_BAR = pci_read_config(mpt->dev, PCIR_BIOS, 4);
	mpt->pci_cfg.IntLine = pci_read_config(mpt->dev, PCIR_INTLINE, 1);
	mpt->pci_cfg.PMCSR = pci_read_config(mpt->dev, 0x44, 4);
}

/* Sets modifiable config registers */
void
mpt_set_config_regs(struct mpt_softc *mpt)
{
	uint32_t val;

#define MPT_CHECK(reg, offset, size)					\
	val = pci_read_config(mpt->dev, offset, size);			\
	if (mpt->pci_cfg.reg != val) {					\
		mpt_prt(mpt,						\
		    "Restoring " #reg " to 0x%X from 0x%X\n",		\
		    mpt->pci_cfg.reg, val);				\
	}

	if (mpt->verbose >= MPT_PRT_DEBUG) {
		MPT_CHECK(Command, PCIR_COMMAND, 2);
		MPT_CHECK(LatencyTimer_LineSize, PCIR_CACHELNSZ, 2);
		MPT_CHECK(IO_BAR, PCIR_BAR(0), 4);
		MPT_CHECK(Mem0_BAR[0], PCIR_BAR(1), 4);
		MPT_CHECK(Mem0_BAR[1], PCIR_BAR(2), 4);
		MPT_CHECK(Mem1_BAR[0], PCIR_BAR(3), 4);
		MPT_CHECK(Mem1_BAR[1], PCIR_BAR(4), 4);
		MPT_CHECK(ROM_BAR, PCIR_BIOS, 4);
		MPT_CHECK(IntLine, PCIR_INTLINE, 1);
		MPT_CHECK(PMCSR, 0x44, 4);
	}
#undef MPT_CHECK

	pci_write_config(mpt->dev, PCIR_COMMAND, mpt->pci_cfg.Command, 2);
	pci_write_config(mpt->dev, PCIR_CACHELNSZ,
	    mpt->pci_cfg.LatencyTimer_LineSize, 2);
	pci_write_config(mpt->dev, PCIR_BAR(0), mpt->pci_cfg.IO_BAR, 4);
	pci_write_config(mpt->dev, PCIR_BAR(1), mpt->pci_cfg.Mem0_BAR[0], 4);
	pci_write_config(mpt->dev, PCIR_BAR(2), mpt->pci_cfg.Mem0_BAR[1], 4);
	pci_write_config(mpt->dev, PCIR_BAR(3), mpt->pci_cfg.Mem1_BAR[0], 4);
	pci_write_config(mpt->dev, PCIR_BAR(4), mpt->pci_cfg.Mem1_BAR[1], 4);
	pci_write_config(mpt->dev, PCIR_BIOS, mpt->pci_cfg.ROM_BAR, 4);
	pci_write_config(mpt->dev, PCIR_INTLINE, mpt->pci_cfg.IntLine, 1);
	pci_write_config(mpt->dev, 0x44, mpt->pci_cfg.PMCSR, 4);
}

static void
mpt_pci_intr(void *arg)
{
	struct mpt_softc *mpt;

	mpt = (struct mpt_softc *)arg;
	MPT_LOCK(mpt);
	mpt_intr(mpt);
	MPT_UNLOCK(mpt);
}