xref: /titanic_51/usr/src/uts/common/io/asy.c (revision 395a144690f7fe586ecb8db5dbd13cf2672a0092)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*	Copyright (c) 1990, 1991 UNIX System Laboratories, Inc.	*/
23 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989, 1990 AT&T	*/
24 /*	  All Rights Reserved					*/
25 
26 /*
27  * Copyright (c) 1992, 2010, Oracle and/or its affiliates. All rights reserved.
28  * Copyright 2012 Milan Jurik. All rights reserved.
29  * Copyright 2023 Oxide Computer Company
30  */
31 
32 
33 /*
34  * Serial I/O driver for 8250/16450/16550A/16650/16750 chips.
35  */
36 
37 #include <sys/param.h>
38 #include <sys/types.h>
39 #include <sys/signal.h>
40 #include <sys/stream.h>
41 #include <sys/termio.h>
42 #include <sys/errno.h>
43 #include <sys/file.h>
44 #include <sys/cmn_err.h>
45 #include <sys/stropts.h>
46 #include <sys/strsubr.h>
47 #include <sys/strtty.h>
48 #include <sys/debug.h>
49 #include <sys/kbio.h>
50 #include <sys/cred.h>
51 #include <sys/stat.h>
52 #include <sys/consdev.h>
53 #include <sys/mkdev.h>
54 #include <sys/kmem.h>
55 #include <sys/cred.h>
56 #include <sys/strsun.h>
57 #ifdef DEBUG
58 #include <sys/promif.h>
59 #endif
60 #include <sys/modctl.h>
61 #include <sys/ddi.h>
62 #include <sys/sunddi.h>
63 #include <sys/pci.h>
64 #include <sys/asy.h>
65 #include <sys/policy.h>
66 
67 /*
68  * set the RX FIFO trigger_level to half the RX FIFO size for now
69  * we may want to make this configurable later.
70  */
71 static	int asy_trig_level = FIFO_TRIG_8;
72 
73 int asy_drain_check = 15000000;		/* tunable: exit drain check time */
74 int asy_min_dtr_low = 500000;		/* tunable: minimum DTR down time */
75 int asy_min_utbrk = 100000;		/* tunable: minumum untimed brk time */
76 
77 int asymaxchip = ASY16750;	/* tunable: limit chip support we look for */
78 
79 /*
80  * Just in case someone has a chip with broken loopback mode, we provide a
81  * means to disable the loopback test. By default, we only loopback test
82  * UARTs which look like they have FIFOs bigger than 16 bytes.
83  * Set to 0 to suppress test, or to 2 to enable test on any size FIFO.
84  */
85 int asy_fifo_test = 1;		/* tunable: set to 0, 1, or 2 */
86 
87 /*
88  * Allow ability to switch off testing of the scratch register.
89  * Some UART emulators might not have it. This will also disable the test
90  * for Exar/Startech ST16C650, as that requires use of the SCR register.
91  */
92 int asy_scr_test = 1;		/* tunable: set to 0 to disable SCR reg test */
93 
94 /*
95  * As we don't yet support on-chip flow control, it's a bad idea to put a
96  * large number of characters in the TX FIFO, since if other end tells us
97  * to stop transmitting, we can only stop filling the TX FIFO, but it will
98  * still carry on draining by itself, so remote end still gets what's left
99  * in the FIFO.
100  */
101 int asy_max_tx_fifo = 16;	/* tunable: max fill of TX FIFO */
102 
103 #define	async_stopc	async_ttycommon.t_stopc
104 #define	async_startc	async_ttycommon.t_startc
105 
106 #define	ASY_INIT	1
107 #define	ASY_NOINIT	0
108 
109 /* enum value for sw and hw flow control action */
110 typedef enum {
111 	FLOW_CHECK,
112 	FLOW_STOP,
113 	FLOW_START
114 } async_flowc_action;
115 
116 #ifdef DEBUG
117 #define	ASY_DEBUG_INIT	0x0001	/* Output msgs during driver initialization. */
118 #define	ASY_DEBUG_INPUT	0x0002	/* Report characters received during int. */
119 #define	ASY_DEBUG_EOT	0x0004	/* Output msgs when wait for xmit to finish. */
120 #define	ASY_DEBUG_CLOSE	0x0008	/* Output msgs when driver open/close called */
121 #define	ASY_DEBUG_HFLOW	0x0010	/* Output msgs when H/W flowcontrol is active */
122 #define	ASY_DEBUG_PROCS	0x0020	/* Output each proc name as it is entered. */
123 #define	ASY_DEBUG_STATE	0x0040	/* Output value of Interrupt Service Reg. */
124 #define	ASY_DEBUG_INTR	0x0080	/* Output value of Interrupt Service Reg. */
125 #define	ASY_DEBUG_OUT	0x0100	/* Output msgs about output events. */
126 #define	ASY_DEBUG_BUSY	0x0200	/* Output msgs when xmit is enabled/disabled */
127 #define	ASY_DEBUG_MODEM	0x0400	/* Output msgs about modem status & control. */
128 #define	ASY_DEBUG_MODM2	0x0800	/* Output msgs about modem status & control. */
129 #define	ASY_DEBUG_IOCTL	0x1000	/* Output msgs about ioctl messages. */
130 #define	ASY_DEBUG_CHIP	0x2000	/* Output msgs about chip identification. */
131 #define	ASY_DEBUG_SFLOW	0x4000	/* Output msgs when S/W flowcontrol is active */
132 #define	ASY_DEBUG(x) (debug & (x))
133 static	int debug  = 0;
134 #else
135 #define	ASY_DEBUG(x) B_FALSE
136 #endif
137 
138 /* pnpISA compressed device ids */
139 #define	pnpMTS0219 0xb6930219	/* Multitech MT5634ZTX modem */
140 
141 /*
142  * PPS (Pulse Per Second) support.
143  */
144 void ddi_hardpps(struct timeval *, int);
145 /*
146  * This is protected by the asy_excl_hi of the port on which PPS event
147  * handling is enabled.  Note that only one port should have this enabled at
148  * any one time.  Enabling PPS handling on multiple ports will result in
149  * unpredictable (but benign) results.
150  */
151 static struct ppsclockev asy_ppsev;
152 
153 #ifdef PPSCLOCKLED
154 /* XXX Use these to observe PPS latencies and jitter on a scope */
155 #define	LED_ON
156 #define	LED_OFF
157 #else
158 #define	LED_ON
159 #define	LED_OFF
160 #endif
161 
162 static	int max_asy_instance = -1;
163 
164 static	uint_t	asysoftintr(caddr_t intarg);
165 static	uint_t	asyintr(caddr_t argasy);
166 
167 static boolean_t abort_charseq_recognize(uchar_t ch);
168 
169 /* The async interrupt entry points */
170 static void	async_txint(struct asycom *asy);
171 static void	async_rxint(struct asycom *asy, uchar_t lsr);
172 static void	async_msint(struct asycom *asy);
173 static void	async_softint(struct asycom *asy);
174 
175 static void	async_ioctl(struct asyncline *async, queue_t *q, mblk_t *mp);
176 static void	async_reioctl(void *unit);
177 static void	async_iocdata(queue_t *q, mblk_t *mp);
178 static void	async_restart(void *arg);
179 static void	async_start(struct asyncline *async);
180 static void	async_nstart(struct asyncline *async, int mode);
181 static void	async_resume(struct asyncline *async);
182 static void	asy_program(struct asycom *asy, int mode);
183 static void	asyinit(struct asycom *asy);
184 static void	asy_waiteot(struct asycom *asy);
185 static void	asyputchar(cons_polledio_arg_t, uchar_t c);
186 static int	asygetchar(cons_polledio_arg_t);
187 static boolean_t	asyischar(cons_polledio_arg_t);
188 
189 static int	asymctl(struct asycom *, int, int);
190 static int	asytodm(int, int);
191 static int	dmtoasy(int);
192 /*PRINTFLIKE2*/
193 static void	asyerror(int level, const char *fmt, ...) __KPRINTFLIKE(2);
194 static void	asy_parse_mode(dev_info_t *devi, struct asycom *asy);
195 static void	asy_soft_state_free(struct asycom *);
196 static char	*asy_hw_name(struct asycom *asy);
197 static void	async_hold_utbrk(void *arg);
198 static void	async_resume_utbrk(struct asyncline *async);
199 static void	async_dtr_free(struct asyncline *async);
200 static int	asy_identify_chip(dev_info_t *devi, struct asycom *asy);
201 static void	asy_reset_fifo(struct asycom *asy, uchar_t flags);
202 static int	asy_getproperty(dev_info_t *devi, struct asycom *asy,
203 		    const char *property);
204 static boolean_t	async_flowcontrol_sw_input(struct asycom *asy,
205 			    async_flowc_action onoff, int type);
206 static void	async_flowcontrol_sw_output(struct asycom *asy,
207 		    async_flowc_action onoff);
208 static void	async_flowcontrol_hw_input(struct asycom *asy,
209 		    async_flowc_action onoff, int type);
210 static void	async_flowcontrol_hw_output(struct asycom *asy,
211 		    async_flowc_action onoff);
212 
213 #define	GET_PROP(devi, pname, pflag, pval, plen) \
214 		(ddi_prop_op(DDI_DEV_T_ANY, (devi), PROP_LEN_AND_VAL_BUF, \
215 		(pflag), (pname), (caddr_t)(pval), (plen)))
216 
217 kmutex_t asy_glob_lock; /* lock protecting global data manipulation */
218 void *asy_soft_state;
219 
220 /* Standard COM port I/O addresses */
221 static const int standard_com_ports[] = {
222 	COM1_IOADDR, COM2_IOADDR, COM3_IOADDR, COM4_IOADDR
223 };
224 
225 static int *com_ports;
226 static uint_t num_com_ports;
227 
228 #ifdef	DEBUG
229 /*
230  * Set this to true to make the driver pretend to do a suspend.  Useful
231  * for debugging suspend/resume code with a serial debugger.
232  */
233 boolean_t	asy_nosuspend = B_FALSE;
234 #endif
235 
236 
237 /*
238  * Baud rate table. Indexed by #defines found in sys/termios.h
239  */
240 ushort_t asyspdtab[] = {
241 	0,	/* 0 baud rate */
242 	0x900,	/* 50 baud rate */
243 	0x600,	/* 75 baud rate */
244 	0x417,	/* 110 baud rate (%0.026) */
245 	0x359,	/* 134 baud rate (%0.058) */
246 	0x300,	/* 150 baud rate */
247 	0x240,	/* 200 baud rate */
248 	0x180,	/* 300 baud rate */
249 	0x0c0,	/* 600 baud rate */
250 	0x060,	/* 1200 baud rate */
251 	0x040,	/* 1800 baud rate */
252 	0x030,	/* 2400 baud rate */
253 	0x018,	/* 4800 baud rate */
254 	0x00c,	/* 9600 baud rate */
255 	0x006,	/* 19200 baud rate */
256 	0x003,	/* 38400 baud rate */
257 
258 	0x002,	/* 57600 baud rate */
259 	0x0,	/* 76800 baud rate not supported */
260 	0x001,	/* 115200 baud rate */
261 	0x0,	/* 153600 baud rate not supported */
262 	0x0,	/* 0x8002 (SMC chip) 230400 baud rate not supported */
263 	0x0,	/* 307200 baud rate not supported */
264 	0x0,	/* 0x8001 (SMC chip) 460800 baud rate not supported */
265 	0x0,	/* unused */
266 	0x0,	/* unused */
267 	0x0,	/* unused */
268 	0x0,	/* unused */
269 	0x0,	/* unused */
270 	0x0,	/* unused */
271 	0x0,	/* unused */
272 	0x0,	/* unused */
273 	0x0,	/* unused */
274 };
275 
276 static int asyrsrv(queue_t *q);
277 static int asyopen(queue_t *rq, dev_t *dev, int flag, int sflag, cred_t *cr);
278 static int asyclose(queue_t *q, int flag, cred_t *credp);
279 static int asywputdo(queue_t *q, mblk_t *mp, boolean_t);
280 static int asywput(queue_t *q, mblk_t *mp);
281 
282 struct module_info asy_info = {
283 	0,
284 	"asy",
285 	0,
286 	INFPSZ,
287 	4096,
288 	128
289 };
290 
291 static struct qinit asy_rint = {
292 	putq,
293 	asyrsrv,
294 	asyopen,
295 	asyclose,
296 	NULL,
297 	&asy_info,
298 	NULL
299 };
300 
301 static struct qinit asy_wint = {
302 	asywput,
303 	NULL,
304 	NULL,
305 	NULL,
306 	NULL,
307 	&asy_info,
308 	NULL
309 };
310 
311 struct streamtab asy_str_info = {
312 	&asy_rint,
313 	&asy_wint,
314 	NULL,
315 	NULL
316 };
317 
318 static int asyinfo(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg,
319 		void **result);
320 static int asyprobe(dev_info_t *);
321 static int asyattach(dev_info_t *, ddi_attach_cmd_t);
322 static int asydetach(dev_info_t *, ddi_detach_cmd_t);
323 static int asyquiesce(dev_info_t *);
324 
325 static 	struct cb_ops cb_asy_ops = {
326 	nodev,			/* cb_open */
327 	nodev,			/* cb_close */
328 	nodev,			/* cb_strategy */
329 	nodev,			/* cb_print */
330 	nodev,			/* cb_dump */
331 	nodev,			/* cb_read */
332 	nodev,			/* cb_write */
333 	nodev,			/* cb_ioctl */
334 	nodev,			/* cb_devmap */
335 	nodev,			/* cb_mmap */
336 	nodev,			/* cb_segmap */
337 	nochpoll,		/* cb_chpoll */
338 	ddi_prop_op,		/* cb_prop_op */
339 	&asy_str_info,		/* cb_stream */
340 	D_MP			/* cb_flag */
341 };
342 
343 struct dev_ops asy_ops = {
344 	DEVO_REV,		/* devo_rev */
345 	0,			/* devo_refcnt */
346 	asyinfo,		/* devo_getinfo */
347 	nulldev,		/* devo_identify */
348 	asyprobe,		/* devo_probe */
349 	asyattach,		/* devo_attach */
350 	asydetach,		/* devo_detach */
351 	nodev,			/* devo_reset */
352 	&cb_asy_ops,		/* devo_cb_ops */
353 	NULL,			/* devo_bus_ops */
354 	NULL,			/* power */
355 	asyquiesce,		/* quiesce */
356 };
357 
358 static struct modldrv modldrv = {
359 	&mod_driverops, /* Type of module.  This one is a driver */
360 	"ASY driver",
361 	&asy_ops,	/* driver ops */
362 };
363 
364 static struct modlinkage modlinkage = {
365 	MODREV_1,
366 	(void *)&modldrv,
367 	NULL
368 };
369 
370 int
371 _init(void)
372 {
373 	int i;
374 
375 	i = ddi_soft_state_init(&asy_soft_state, sizeof (struct asycom), 2);
376 	if (i == 0) {
377 		mutex_init(&asy_glob_lock, NULL, MUTEX_DRIVER, NULL);
378 		if ((i = mod_install(&modlinkage)) != 0) {
379 			mutex_destroy(&asy_glob_lock);
380 			ddi_soft_state_fini(&asy_soft_state);
381 		} else {
382 			DEBUGCONT2(ASY_DEBUG_INIT, "%s, debug = %x\n",
383 			    modldrv.drv_linkinfo, debug);
384 		}
385 	}
386 	return (i);
387 }
388 
389 int
390 _fini(void)
391 {
392 	int i;
393 
394 	if ((i = mod_remove(&modlinkage)) == 0) {
395 		DEBUGCONT1(ASY_DEBUG_INIT, "%s unloading\n",
396 		    modldrv.drv_linkinfo);
397 		ASSERT(max_asy_instance == -1);
398 		mutex_destroy(&asy_glob_lock);
399 		/* free "motherboard-serial-ports" property if allocated */
400 		if (com_ports != NULL && com_ports != (int *)standard_com_ports)
401 			ddi_prop_free(com_ports);
402 		com_ports = NULL;
403 		ddi_soft_state_fini(&asy_soft_state);
404 	}
405 	return (i);
406 }
407 
408 int
409 _info(struct modinfo *modinfop)
410 {
411 	return (mod_info(&modlinkage, modinfop));
412 }
413 
414 void
415 async_put_suspq(struct asycom *asy, mblk_t *mp)
416 {
417 	struct asyncline *async = asy->asy_priv;
418 
419 	ASSERT(mutex_owned(&asy->asy_excl));
420 
421 	if (async->async_suspqf == NULL)
422 		async->async_suspqf = mp;
423 	else
424 		async->async_suspqb->b_next = mp;
425 
426 	async->async_suspqb = mp;
427 }
428 
429 static mblk_t *
430 async_get_suspq(struct asycom *asy)
431 {
432 	struct asyncline *async = asy->asy_priv;
433 	mblk_t *mp;
434 
435 	ASSERT(mutex_owned(&asy->asy_excl));
436 
437 	if ((mp = async->async_suspqf) != NULL) {
438 		async->async_suspqf = mp->b_next;
439 		mp->b_next = NULL;
440 	} else {
441 		async->async_suspqb = NULL;
442 	}
443 	return (mp);
444 }
445 
446 static void
447 async_process_suspq(struct asycom *asy)
448 {
449 	struct asyncline *async = asy->asy_priv;
450 	mblk_t *mp;
451 
452 	ASSERT(mutex_owned(&asy->asy_excl));
453 
454 	while ((mp = async_get_suspq(asy)) != NULL) {
455 		queue_t *q;
456 
457 		q = async->async_ttycommon.t_writeq;
458 		ASSERT(q != NULL);
459 		mutex_exit(&asy->asy_excl);
460 		(void) asywputdo(q, mp, B_FALSE);
461 		mutex_enter(&asy->asy_excl);
462 	}
463 	async->async_flags &= ~ASYNC_DDI_SUSPENDED;
464 	cv_broadcast(&async->async_flags_cv);
465 }
466 
467 static int
468 asy_get_bus_type(dev_info_t *devinfo)
469 {
470 	char	parent_type[16];
471 	int	parentlen;
472 
473 	parentlen = sizeof (parent_type);
474 
475 	if (ddi_prop_op(DDI_DEV_T_ANY, devinfo, PROP_LEN_AND_VAL_BUF, 0,
476 	    "device_type", (caddr_t)parent_type, &parentlen)
477 	    != DDI_PROP_SUCCESS && ddi_prop_op(DDI_DEV_T_ANY, devinfo,
478 	    PROP_LEN_AND_VAL_BUF, 0, "bus-type", (caddr_t)parent_type,
479 	    &parentlen) != DDI_PROP_SUCCESS) {
480 			cmn_err(CE_WARN,
481 			    "asy: can't figure out device type for"
482 			    " parent \"%s\"",
483 			    ddi_get_name(ddi_get_parent(devinfo)));
484 			return (ASY_BUS_UNKNOWN);
485 	}
486 	if (strcmp(parent_type, "isa") == 0)
487 		return (ASY_BUS_ISA);
488 	else if (strcmp(parent_type, "pci") == 0)
489 		return (ASY_BUS_PCI);
490 	else
491 		return (ASY_BUS_UNKNOWN);
492 }
493 
494 static int
495 asy_get_io_regnum_pci(dev_info_t *devi, struct asycom *asy)
496 {
497 	int reglen, nregs;
498 	int regnum, i;
499 	uint64_t size;
500 	struct pci_phys_spec *reglist;
501 
502 	if (ddi_getlongprop(DDI_DEV_T_ANY, devi, DDI_PROP_DONTPASS,
503 	    "reg", (caddr_t)&reglist, &reglen) != DDI_PROP_SUCCESS) {
504 		cmn_err(CE_WARN, "asy_get_io_regnum_pci: reg property"
505 		    " not found in devices property list");
506 		return (-1);
507 	}
508 
509 	/*
510 	 * PCI devices are assumed to not have broken FIFOs;
511 	 * Agere/Lucent Venus PCI modem chipsets are an example
512 	 */
513 	if (asy)
514 		asy->asy_flags2 |= ASY2_NO_LOOPBACK;
515 
516 	regnum = -1;
517 	nregs = reglen / sizeof (*reglist);
518 	for (i = 0; i < nregs; i++) {
519 		switch (reglist[i].pci_phys_hi & PCI_ADDR_MASK) {
520 		case PCI_ADDR_IO:		/* I/O bus reg property */
521 			if (regnum == -1) /* use only the first one */
522 				regnum = i;
523 			break;
524 
525 		default:
526 			break;
527 		}
528 	}
529 
530 	/* check for valid count of registers */
531 	if (regnum >= 0) {
532 		size = ((uint64_t)reglist[regnum].pci_size_low) |
533 		    ((uint64_t)reglist[regnum].pci_size_hi) << 32;
534 		if (size < 8)
535 			regnum = -1;
536 	}
537 	kmem_free(reglist, reglen);
538 	return (regnum);
539 }
540 
541 static int
542 asy_get_io_regnum_isa(dev_info_t *devi, struct asycom *asy)
543 {
544 	int reglen, nregs;
545 	int regnum, i;
546 	struct {
547 		uint_t bustype;
548 		int base;
549 		int size;
550 	} *reglist;
551 
552 	if (ddi_getlongprop(DDI_DEV_T_ANY, devi, DDI_PROP_DONTPASS,
553 	    "reg", (caddr_t)&reglist, &reglen) != DDI_PROP_SUCCESS) {
554 		cmn_err(CE_WARN, "asy_get_io_regnum: reg property not found "
555 		    "in devices property list");
556 		return (-1);
557 	}
558 
559 	regnum = -1;
560 	nregs = reglen / sizeof (*reglist);
561 	for (i = 0; i < nregs; i++) {
562 		switch (reglist[i].bustype) {
563 		case 1:			/* I/O bus reg property */
564 			if (regnum == -1) /* only use the first one */
565 				regnum = i;
566 			break;
567 
568 		case pnpMTS0219:	/* Multitech MT5634ZTX modem */
569 			/* Venus chipset can't do loopback test */
570 			if (asy)
571 				asy->asy_flags2 |= ASY2_NO_LOOPBACK;
572 			break;
573 
574 		default:
575 			break;
576 		}
577 	}
578 
579 	/* check for valid count of registers */
580 	if ((regnum < 0) || (reglist[regnum].size < 8))
581 		regnum = -1;
582 	kmem_free(reglist, reglen);
583 	return (regnum);
584 }
585 
586 static int
587 asy_get_io_regnum(dev_info_t *devinfo, struct asycom *asy)
588 {
589 	switch (asy_get_bus_type(devinfo)) {
590 	case ASY_BUS_ISA:
591 		return (asy_get_io_regnum_isa(devinfo, asy));
592 	case ASY_BUS_PCI:
593 		return (asy_get_io_regnum_pci(devinfo, asy));
594 	default:
595 		return (-1);
596 	}
597 }
598 
599 static int
600 asydetach(dev_info_t *devi, ddi_detach_cmd_t cmd)
601 {
602 	int instance;
603 	struct asycom *asy;
604 	struct asyncline *async;
605 
606 	instance = ddi_get_instance(devi);	/* find out which unit */
607 
608 	asy = ddi_get_soft_state(asy_soft_state, instance);
609 	if (asy == NULL)
610 		return (DDI_FAILURE);
611 	async = asy->asy_priv;
612 
613 	switch (cmd) {
614 	case DDI_DETACH:
615 		DEBUGNOTE2(ASY_DEBUG_INIT, "asy%d: %s shutdown.",
616 		    instance, asy_hw_name(asy));
617 
618 		/* cancel DTR hold timeout */
619 		if (async->async_dtrtid != 0) {
620 			(void) untimeout(async->async_dtrtid);
621 			async->async_dtrtid = 0;
622 		}
623 
624 		/* remove all minor device node(s) for this device */
625 		ddi_remove_minor_node(devi, NULL);
626 
627 		mutex_destroy(&asy->asy_excl);
628 		mutex_destroy(&asy->asy_excl_hi);
629 		cv_destroy(&async->async_flags_cv);
630 		ddi_remove_intr(devi, 0, asy->asy_iblock);
631 		ddi_regs_map_free(&asy->asy_iohandle);
632 		ddi_remove_softintr(asy->asy_softintr_id);
633 		mutex_destroy(&asy->asy_soft_lock);
634 		asy_soft_state_free(asy);
635 		DEBUGNOTE1(ASY_DEBUG_INIT, "asy%d: shutdown complete",
636 		    instance);
637 		break;
638 	case DDI_SUSPEND:
639 		{
640 		unsigned i;
641 		uchar_t lsr;
642 
643 #ifdef	DEBUG
644 		if (asy_nosuspend)
645 			return (DDI_SUCCESS);
646 #endif
647 		mutex_enter(&asy->asy_excl);
648 
649 		ASSERT(async->async_ops >= 0);
650 		while (async->async_ops > 0)
651 			cv_wait(&async->async_ops_cv, &asy->asy_excl);
652 
653 		async->async_flags |= ASYNC_DDI_SUSPENDED;
654 
655 		/* Wait for timed break and delay to complete */
656 		while ((async->async_flags & (ASYNC_BREAK|ASYNC_DELAY))) {
657 			if (cv_wait_sig(&async->async_flags_cv, &asy->asy_excl)
658 			    == 0) {
659 				async_process_suspq(asy);
660 				mutex_exit(&asy->asy_excl);
661 				return (DDI_FAILURE);
662 			}
663 		}
664 
665 		/* Clear untimed break */
666 		if (async->async_flags & ASYNC_OUT_SUSPEND)
667 			async_resume_utbrk(async);
668 
669 		mutex_exit(&asy->asy_excl);
670 
671 		mutex_enter(&asy->asy_soft_sr);
672 		mutex_enter(&asy->asy_excl);
673 		if (async->async_wbufcid != 0) {
674 			bufcall_id_t bcid = async->async_wbufcid;
675 			async->async_wbufcid = 0;
676 			async->async_flags |= ASYNC_RESUME_BUFCALL;
677 			mutex_exit(&asy->asy_excl);
678 			unbufcall(bcid);
679 			mutex_enter(&asy->asy_excl);
680 		}
681 		mutex_enter(&asy->asy_excl_hi);
682 
683 		/* Disable interrupts from chip */
684 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
685 		asy->asy_flags |= ASY_DDI_SUSPENDED;
686 
687 		/*
688 		 * Hardware interrupts are disabled we can drop our high level
689 		 * lock and proceed.
690 		 */
691 		mutex_exit(&asy->asy_excl_hi);
692 
693 		/* Process remaining RX characters and RX errors, if any */
694 		lsr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR);
695 		async_rxint(asy, lsr);
696 
697 		/* Wait for TX to drain */
698 		for (i = 1000; i > 0; i--) {
699 			lsr = ddi_get8(asy->asy_iohandle,
700 			    asy->asy_ioaddr + LSR);
701 			if ((lsr & (XSRE | XHRE)) == (XSRE | XHRE))
702 				break;
703 			delay(drv_usectohz(10000));
704 		}
705 		if (i == 0)
706 			cmn_err(CE_WARN,
707 			    "asy: transmitter wasn't drained before "
708 			    "driver was suspended");
709 
710 		mutex_exit(&asy->asy_excl);
711 		mutex_exit(&asy->asy_soft_sr);
712 		break;
713 	}
714 	default:
715 		return (DDI_FAILURE);
716 	}
717 
718 	return (DDI_SUCCESS);
719 }
720 
721 /*
722  * asyprobe
723  * We don't bother probing for the hardware, as since Solaris 2.6, device
724  * nodes are only created for auto-detected hardware or nodes explicitly
725  * created by the user, e.g. via the DCA. However, we should check the
726  * device node is at least vaguely usable, i.e. we have a block of 8 i/o
727  * ports. This prevents attempting to attach to bogus serial ports which
728  * some BIOSs still partially report when they are disabled in the BIOS.
729  */
730 static int
731 asyprobe(dev_info_t *devi)
732 {
733 	return ((asy_get_io_regnum(devi, NULL) < 0) ?
734 	    DDI_PROBE_FAILURE : DDI_PROBE_DONTCARE);
735 }
736 
737 static int
738 asyattach(dev_info_t *devi, ddi_attach_cmd_t cmd)
739 {
740 	int instance;
741 	int mcr;
742 	int ret;
743 	int regnum = 0;
744 	int i;
745 	struct asycom *asy;
746 	char name[ASY_MINOR_LEN];
747 	int status;
748 	static ddi_device_acc_attr_t ioattr = {
749 		DDI_DEVICE_ATTR_V0,
750 		DDI_NEVERSWAP_ACC,
751 		DDI_STRICTORDER_ACC,
752 	};
753 
754 	instance = ddi_get_instance(devi);	/* find out which unit */
755 
756 	switch (cmd) {
757 	case DDI_ATTACH:
758 		break;
759 	case DDI_RESUME:
760 	{
761 		struct asyncline *async;
762 
763 #ifdef	DEBUG
764 		if (asy_nosuspend)
765 			return (DDI_SUCCESS);
766 #endif
767 		asy = ddi_get_soft_state(asy_soft_state, instance);
768 		if (asy == NULL)
769 			return (DDI_FAILURE);
770 
771 		mutex_enter(&asy->asy_soft_sr);
772 		mutex_enter(&asy->asy_excl);
773 		mutex_enter(&asy->asy_excl_hi);
774 
775 		async = asy->asy_priv;
776 		/* Disable interrupts */
777 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
778 		if (asy_identify_chip(devi, asy) != DDI_SUCCESS) {
779 			mutex_exit(&asy->asy_excl_hi);
780 			mutex_exit(&asy->asy_excl);
781 			mutex_exit(&asy->asy_soft_sr);
782 			cmn_err(CE_WARN, "!Cannot identify UART chip at %p\n",
783 			    (void *)asy->asy_ioaddr);
784 			return (DDI_FAILURE);
785 		}
786 		asy->asy_flags &= ~ASY_DDI_SUSPENDED;
787 		if (async->async_flags & ASYNC_ISOPEN) {
788 			asy_program(asy, ASY_INIT);
789 			/* Kick off output */
790 			if (async->async_ocnt > 0) {
791 				async_resume(async);
792 			} else {
793 				mutex_exit(&asy->asy_excl_hi);
794 				if (async->async_xmitblk)
795 					freeb(async->async_xmitblk);
796 				async->async_xmitblk = NULL;
797 				async_start(async);
798 				mutex_enter(&asy->asy_excl_hi);
799 			}
800 			ASYSETSOFT(asy);
801 		}
802 		mutex_exit(&asy->asy_excl_hi);
803 		mutex_exit(&asy->asy_excl);
804 		mutex_exit(&asy->asy_soft_sr);
805 
806 		mutex_enter(&asy->asy_excl);
807 		if (async->async_flags & ASYNC_RESUME_BUFCALL) {
808 			async->async_wbufcid = bufcall(async->async_wbufcds,
809 			    BPRI_HI, (void (*)(void *)) async_reioctl,
810 			    (void *)(intptr_t)async->async_common->asy_unit);
811 			async->async_flags &= ~ASYNC_RESUME_BUFCALL;
812 		}
813 		async_process_suspq(asy);
814 		mutex_exit(&asy->asy_excl);
815 		return (DDI_SUCCESS);
816 	}
817 	default:
818 		return (DDI_FAILURE);
819 	}
820 
821 	ret = ddi_soft_state_zalloc(asy_soft_state, instance);
822 	if (ret != DDI_SUCCESS)
823 		return (DDI_FAILURE);
824 	asy = ddi_get_soft_state(asy_soft_state, instance);
825 	ASSERT(asy != NULL);	/* can't fail - we only just allocated it */
826 	asy->asy_unit = instance;
827 	mutex_enter(&asy_glob_lock);
828 	if (instance > max_asy_instance)
829 		max_asy_instance = instance;
830 	mutex_exit(&asy_glob_lock);
831 
832 	regnum = asy_get_io_regnum(devi, asy);
833 
834 	if (regnum < 0 ||
835 	    ddi_regs_map_setup(devi, regnum, (caddr_t *)&asy->asy_ioaddr,
836 	    (offset_t)0, (offset_t)0, &ioattr, &asy->asy_iohandle)
837 	    != DDI_SUCCESS) {
838 		cmn_err(CE_WARN, "asy%d: could not map UART registers @ %p",
839 		    instance, (void *)asy->asy_ioaddr);
840 
841 		asy_soft_state_free(asy);
842 		return (DDI_FAILURE);
843 	}
844 
845 	DEBUGCONT2(ASY_DEBUG_INIT, "asy%dattach: UART @ %p\n",
846 	    instance, (void *)asy->asy_ioaddr);
847 
848 	mutex_enter(&asy_glob_lock);
849 	if (com_ports == NULL) {	/* need to initialize com_ports */
850 		if (ddi_prop_lookup_int_array(DDI_DEV_T_ANY, devi, 0,
851 		    "motherboard-serial-ports", &com_ports, &num_com_ports) !=
852 		    DDI_PROP_SUCCESS) {
853 			/* Use our built-in COM[1234] values */
854 			com_ports = (int *)standard_com_ports;
855 			num_com_ports = sizeof (standard_com_ports) /
856 			    sizeof (standard_com_ports[0]);
857 		}
858 		if (num_com_ports > 10) {
859 			/* We run out of single digits for device properties */
860 			num_com_ports = 10;
861 			cmn_err(CE_WARN,
862 			    "More than %d motherboard-serial-ports",
863 			    num_com_ports);
864 		}
865 	}
866 	mutex_exit(&asy_glob_lock);
867 
868 	/*
869 	 * Lookup the i/o address to see if this is a standard COM port
870 	 * in which case we assign it the correct tty[a-d] to match the
871 	 * COM port number, or some other i/o address in which case it
872 	 * will be assigned /dev/term/[0123...] in some rather arbitrary
873 	 * fashion.
874 	 */
875 
876 	for (i = 0; i < num_com_ports; i++) {
877 		if (asy->asy_ioaddr == (uint8_t *)(uintptr_t)com_ports[i]) {
878 			asy->asy_com_port = i + 1;
879 			break;
880 		}
881 	}
882 
883 	/*
884 	 * It appears that there was async hardware that on reset
885 	 * did not clear ICR.  Hence when we get to
886 	 * ddi_get_iblock_cookie below, this hardware would cause
887 	 * the system to hang if there was input available.
888 	 */
889 
890 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0x00);
891 
892 	/* establish default usage */
893 	asy->asy_mcr |= RTS|DTR;		/* do use RTS/DTR after open */
894 	asy->asy_lcr = STOP1|BITS8;		/* default to 1 stop 8 bits */
895 	asy->asy_bidx = B9600;			/* default to 9600  */
896 #ifdef DEBUG
897 	asy->asy_msint_cnt = 0;			/* # of times in async_msint */
898 #endif
899 	mcr = 0;				/* don't enable until open */
900 
901 	if (asy->asy_com_port != 0) {
902 		/*
903 		 * For motherboard ports, emulate tty eeprom properties.
904 		 * Actually, we can't tell if a port is motherboard or not,
905 		 * so for "motherboard ports", read standard DOS COM ports.
906 		 */
907 		switch (asy_getproperty(devi, asy, "ignore-cd")) {
908 		case 0:				/* *-ignore-cd=False */
909 			DEBUGCONT1(ASY_DEBUG_MODEM,
910 			    "asy%dattach: clear ASY_IGNORE_CD\n", instance);
911 			asy->asy_flags &= ~ASY_IGNORE_CD; /* wait for cd */
912 			break;
913 		case 1:				/* *-ignore-cd=True */
914 			/*FALLTHRU*/
915 		default:			/* *-ignore-cd not defined */
916 			/*
917 			 * We set rather silly defaults of soft carrier on
918 			 * and DTR/RTS raised here because it might be that
919 			 * one of the motherboard ports is the system console.
920 			 */
921 			DEBUGCONT1(ASY_DEBUG_MODEM,
922 			    "asy%dattach: set ASY_IGNORE_CD, set RTS & DTR\n",
923 			    instance);
924 			mcr = asy->asy_mcr;		/* rts/dtr on */
925 			asy->asy_flags |= ASY_IGNORE_CD;	/* ignore cd */
926 			break;
927 		}
928 
929 		/* Property for not raising DTR/RTS */
930 		switch (asy_getproperty(devi, asy, "rts-dtr-off")) {
931 		case 0:				/* *-rts-dtr-off=False */
932 			asy->asy_flags |= ASY_RTS_DTR_OFF;	/* OFF */
933 			mcr = asy->asy_mcr;		/* rts/dtr on */
934 			DEBUGCONT1(ASY_DEBUG_MODEM, "asy%dattach: "
935 			    "ASY_RTS_DTR_OFF set and DTR & RTS set\n",
936 			    instance);
937 			break;
938 		case 1:				/* *-rts-dtr-off=True */
939 			/*FALLTHRU*/
940 		default:			/* *-rts-dtr-off undefined */
941 			break;
942 		}
943 
944 		/* Parse property for tty modes */
945 		asy_parse_mode(devi, asy);
946 	} else {
947 		DEBUGCONT1(ASY_DEBUG_MODEM,
948 		    "asy%dattach: clear ASY_IGNORE_CD, clear RTS & DTR\n",
949 		    instance);
950 		asy->asy_flags &= ~ASY_IGNORE_CD;	/* wait for cd */
951 	}
952 
953 	/*
954 	 * Initialize the port with default settings.
955 	 */
956 
957 	asy->asy_fifo_buf = 1;
958 	asy->asy_use_fifo = FIFO_OFF;
959 
960 	/*
961 	 * Get icookie for mutexes initialization
962 	 */
963 	if ((ddi_get_iblock_cookie(devi, 0, &asy->asy_iblock) !=
964 	    DDI_SUCCESS) ||
965 	    (ddi_get_soft_iblock_cookie(devi, DDI_SOFTINT_MED,
966 	    &asy->asy_soft_iblock) != DDI_SUCCESS)) {
967 		ddi_regs_map_free(&asy->asy_iohandle);
968 		cmn_err(CE_CONT,
969 		    "asy%d: could not hook interrupt for UART @ %p\n",
970 		    instance, (void *)asy->asy_ioaddr);
971 		asy_soft_state_free(asy);
972 		return (DDI_FAILURE);
973 	}
974 
975 	/*
976 	 * Initialize mutexes before accessing the hardware
977 	 */
978 	mutex_init(&asy->asy_soft_lock, NULL, MUTEX_DRIVER,
979 	    (void *)asy->asy_soft_iblock);
980 	mutex_init(&asy->asy_excl, NULL, MUTEX_DRIVER, NULL);
981 	mutex_init(&asy->asy_excl_hi, NULL, MUTEX_DRIVER,
982 	    (void *)asy->asy_iblock);
983 	mutex_init(&asy->asy_soft_sr, NULL, MUTEX_DRIVER,
984 	    (void *)asy->asy_soft_iblock);
985 	mutex_enter(&asy->asy_excl);
986 	mutex_enter(&asy->asy_excl_hi);
987 
988 	if (asy_identify_chip(devi, asy) != DDI_SUCCESS) {
989 		mutex_exit(&asy->asy_excl_hi);
990 		mutex_exit(&asy->asy_excl);
991 		mutex_destroy(&asy->asy_soft_lock);
992 		mutex_destroy(&asy->asy_excl);
993 		mutex_destroy(&asy->asy_excl_hi);
994 		mutex_destroy(&asy->asy_soft_sr);
995 		ddi_regs_map_free(&asy->asy_iohandle);
996 		cmn_err(CE_CONT, "!Cannot identify UART chip at %p\n",
997 		    (void *)asy->asy_ioaddr);
998 		asy_soft_state_free(asy);
999 		return (DDI_FAILURE);
1000 	}
1001 
1002 	/* disable all interrupts */
1003 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
1004 	/* select baud rate generator */
1005 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, DLAB);
1006 	/* Set the baud rate to 9600 */
1007 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + (DAT+DLL),
1008 	    asyspdtab[asy->asy_bidx] & 0xff);
1009 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + (DAT+DLH),
1010 	    (asyspdtab[asy->asy_bidx] >> 8) & 0xff);
1011 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, asy->asy_lcr);
1012 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR, mcr);
1013 
1014 	mutex_exit(&asy->asy_excl_hi);
1015 	mutex_exit(&asy->asy_excl);
1016 
1017 	/*
1018 	 * Set up the other components of the asycom structure for this port.
1019 	 */
1020 	asy->asy_dip = devi;
1021 
1022 	/*
1023 	 * Install per instance software interrupt handler.
1024 	 */
1025 	if (ddi_add_softintr(devi, DDI_SOFTINT_MED,
1026 	    &(asy->asy_softintr_id), NULL, 0, asysoftintr,
1027 	    (caddr_t)asy) != DDI_SUCCESS) {
1028 		mutex_destroy(&asy->asy_soft_lock);
1029 		mutex_destroy(&asy->asy_excl);
1030 		mutex_destroy(&asy->asy_excl_hi);
1031 		ddi_regs_map_free(&asy->asy_iohandle);
1032 		cmn_err(CE_CONT,
1033 		    "Can not set soft interrupt for ASY driver\n");
1034 		asy_soft_state_free(asy);
1035 		return (DDI_FAILURE);
1036 	}
1037 
1038 	mutex_enter(&asy->asy_excl);
1039 	mutex_enter(&asy->asy_excl_hi);
1040 
1041 	/*
1042 	 * Install interrupt handler for this device.
1043 	 */
1044 	if (ddi_add_intr(devi, 0, NULL, 0, asyintr,
1045 	    (caddr_t)asy) != DDI_SUCCESS) {
1046 		mutex_exit(&asy->asy_excl_hi);
1047 		mutex_exit(&asy->asy_excl);
1048 		ddi_remove_softintr(asy->asy_softintr_id);
1049 		mutex_destroy(&asy->asy_soft_lock);
1050 		mutex_destroy(&asy->asy_excl);
1051 		mutex_destroy(&asy->asy_excl_hi);
1052 		ddi_regs_map_free(&asy->asy_iohandle);
1053 		cmn_err(CE_CONT,
1054 		    "Can not set device interrupt for ASY driver\n");
1055 		asy_soft_state_free(asy);
1056 		return (DDI_FAILURE);
1057 	}
1058 
1059 	mutex_exit(&asy->asy_excl_hi);
1060 	mutex_exit(&asy->asy_excl);
1061 
1062 	asyinit(asy);	/* initialize the asyncline structure */
1063 
1064 	/* create minor device nodes for this device */
1065 	if (asy->asy_com_port != 0) {
1066 		/*
1067 		 * For DOS COM ports, add letter suffix so
1068 		 * devfsadm can create correct link names.
1069 		 */
1070 		name[0] = asy->asy_com_port + 'a' - 1;
1071 		name[1] = '\0';
1072 	} else {
1073 		/*
1074 		 * asy port which isn't a standard DOS COM
1075 		 * port gets a numeric name based on instance
1076 		 */
1077 		(void) snprintf(name, ASY_MINOR_LEN, "%d", instance);
1078 	}
1079 	status = ddi_create_minor_node(devi, name, S_IFCHR, instance,
1080 	    asy->asy_com_port != 0 ? DDI_NT_SERIAL_MB : DDI_NT_SERIAL, NULL);
1081 	if (status == DDI_SUCCESS) {
1082 		(void) strcat(name, ",cu");
1083 		status = ddi_create_minor_node(devi, name, S_IFCHR,
1084 		    OUTLINE | instance,
1085 		    asy->asy_com_port != 0 ? DDI_NT_SERIAL_MB_DO :
1086 		    DDI_NT_SERIAL_DO, NULL);
1087 	}
1088 
1089 	if (status != DDI_SUCCESS) {
1090 		struct asyncline *async = asy->asy_priv;
1091 
1092 		ddi_remove_minor_node(devi, NULL);
1093 		ddi_remove_intr(devi, 0, asy->asy_iblock);
1094 		ddi_remove_softintr(asy->asy_softintr_id);
1095 		mutex_destroy(&asy->asy_soft_lock);
1096 		mutex_destroy(&asy->asy_excl);
1097 		mutex_destroy(&asy->asy_excl_hi);
1098 		cv_destroy(&async->async_flags_cv);
1099 		ddi_regs_map_free(&asy->asy_iohandle);
1100 		asy_soft_state_free(asy);
1101 		return (DDI_FAILURE);
1102 	}
1103 
1104 	/*
1105 	 * Fill in the polled I/O structure.
1106 	 */
1107 	asy->polledio.cons_polledio_version = CONSPOLLEDIO_V0;
1108 	asy->polledio.cons_polledio_argument = (cons_polledio_arg_t)asy;
1109 	asy->polledio.cons_polledio_putchar = asyputchar;
1110 	asy->polledio.cons_polledio_getchar = asygetchar;
1111 	asy->polledio.cons_polledio_ischar = asyischar;
1112 	asy->polledio.cons_polledio_enter = NULL;
1113 	asy->polledio.cons_polledio_exit = NULL;
1114 
1115 	ddi_report_dev(devi);
1116 	DEBUGCONT1(ASY_DEBUG_INIT, "asy%dattach: done\n", instance);
1117 	return (DDI_SUCCESS);
1118 }
1119 
1120 /*ARGSUSED*/
1121 static int
1122 asyinfo(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg,
1123 	void **result)
1124 {
1125 	dev_t dev = (dev_t)arg;
1126 	int instance, error;
1127 	struct asycom *asy;
1128 
1129 	instance = UNIT(dev);
1130 
1131 	switch (infocmd) {
1132 	case DDI_INFO_DEVT2DEVINFO:
1133 		asy = ddi_get_soft_state(asy_soft_state, instance);
1134 		if ((asy == NULL) || (asy->asy_dip == NULL))
1135 			error = DDI_FAILURE;
1136 		else {
1137 			*result = (void *) asy->asy_dip;
1138 			error = DDI_SUCCESS;
1139 		}
1140 		break;
1141 	case DDI_INFO_DEVT2INSTANCE:
1142 		*result = (void *)(intptr_t)instance;
1143 		error = DDI_SUCCESS;
1144 		break;
1145 	default:
1146 		error = DDI_FAILURE;
1147 	}
1148 	return (error);
1149 }
1150 
1151 /* asy_getproperty -- walk through all name variants until we find a match */
1152 
1153 static int
1154 asy_getproperty(dev_info_t *devi, struct asycom *asy, const char *property)
1155 {
1156 	int len;
1157 	int ret;
1158 	char letter = asy->asy_com_port + 'a' - 1;	/* for ttya */
1159 	char number = asy->asy_com_port + '0';		/* for COM1 */
1160 	char val[40];
1161 	char name[40];
1162 
1163 	/* Property for ignoring DCD */
1164 	(void) sprintf(name, "tty%c-%s", letter, property);
1165 	len = sizeof (val);
1166 	ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
1167 	if (ret != DDI_PROP_SUCCESS) {
1168 		(void) sprintf(name, "com%c-%s", number, property);
1169 		len = sizeof (val);
1170 		ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
1171 	}
1172 	if (ret != DDI_PROP_SUCCESS) {
1173 		(void) sprintf(name, "tty0%c-%s", number, property);
1174 		len = sizeof (val);
1175 		ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
1176 	}
1177 	if (ret != DDI_PROP_SUCCESS) {
1178 		(void) sprintf(name, "port-%c-%s", letter, property);
1179 		len = sizeof (val);
1180 		ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
1181 	}
1182 	if (ret != DDI_PROP_SUCCESS)
1183 		return (-1);		/* property non-existant */
1184 	if (val[0] == 'f' || val[0] == 'F' || val[0] == '0')
1185 		return (0);		/* property false/0 */
1186 	return (1);			/* property true/!0 */
1187 }
1188 
1189 /* asy_soft_state_free - local wrapper for ddi_soft_state_free(9F) */
1190 
1191 static void
1192 asy_soft_state_free(struct asycom *asy)
1193 {
1194 	mutex_enter(&asy_glob_lock);
1195 	/* If we were the max_asy_instance, work out new value */
1196 	if (asy->asy_unit == max_asy_instance) {
1197 		while (--max_asy_instance >= 0) {
1198 			if (ddi_get_soft_state(asy_soft_state,
1199 			    max_asy_instance) != NULL)
1200 				break;
1201 		}
1202 	}
1203 	mutex_exit(&asy_glob_lock);
1204 
1205 	if (asy->asy_priv != NULL) {
1206 		kmem_free(asy->asy_priv, sizeof (struct asyncline));
1207 		asy->asy_priv = NULL;
1208 	}
1209 	ddi_soft_state_free(asy_soft_state, asy->asy_unit);
1210 }
1211 
1212 static char *
1213 asy_hw_name(struct asycom *asy)
1214 {
1215 	switch (asy->asy_hwtype) {
1216 	case ASY8250A:
1217 		return ("8250A/16450");
1218 	case ASY16550:
1219 		return ("16550");
1220 	case ASY16550A:
1221 		return ("16550A");
1222 	case ASY16650:
1223 		return ("16650");
1224 	case ASY16750:
1225 		return ("16750");
1226 	default:
1227 		DEBUGNOTE2(ASY_DEBUG_INIT,
1228 		    "asy%d: asy_hw_name: unknown asy_hwtype: %d",
1229 		    asy->asy_unit, asy->asy_hwtype);
1230 		return ("?");
1231 	}
1232 }
1233 
1234 static int
1235 asy_identify_chip(dev_info_t *devi, struct asycom *asy)
1236 {
1237 	int ret;
1238 	int mcr;
1239 	dev_t dev;
1240 	uint_t hwtype;
1241 
1242 	if (asy_scr_test) {
1243 		/* Check scratch register works. */
1244 
1245 		/* write to scratch register */
1246 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + SCR, SCRTEST);
1247 		/* make sure that pattern doesn't just linger on the bus */
1248 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + FIFOR, 0x00);
1249 		/* read data back from scratch register */
1250 		ret = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + SCR);
1251 		if (ret != SCRTEST) {
1252 			/*
1253 			 * Scratch register not working.
1254 			 * Probably not an async chip.
1255 			 * 8250 and 8250B don't have scratch registers,
1256 			 * but only worked in ancient PC XT's anyway.
1257 			 */
1258 			cmn_err(CE_CONT, "!asy%d: UART @ %p "
1259 			    "scratch register: expected 0x5a, got 0x%02x\n",
1260 			    asy->asy_unit, (void *)asy->asy_ioaddr, ret);
1261 			return (DDI_FAILURE);
1262 		}
1263 	}
1264 	/*
1265 	 * Use 16550 fifo reset sequence specified in NS application
1266 	 * note. Disable fifos until chip is initialized.
1267 	 */
1268 	ddi_put8(asy->asy_iohandle,
1269 	    asy->asy_ioaddr + FIFOR, 0x00);	/* clear */
1270 	ddi_put8(asy->asy_iohandle,
1271 	    asy->asy_ioaddr + FIFOR, FIFO_ON);	/* enable */
1272 	ddi_put8(asy->asy_iohandle,
1273 	    asy->asy_ioaddr + FIFOR, FIFO_ON | FIFORXFLSH);
1274 						/* reset */
1275 	if (asymaxchip >= ASY16650 && asy_scr_test) {
1276 		/*
1277 		 * Reset 16650 enhanced regs also, in case we have one of these
1278 		 */
1279 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1280 		    EFRACCESS);
1281 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + EFR,
1282 		    0);
1283 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1284 		    STOP1|BITS8);
1285 	}
1286 
1287 	/*
1288 	 * See what sort of FIFO we have.
1289 	 * Try enabling it and see what chip makes of this.
1290 	 */
1291 
1292 	asy->asy_fifor = 0;
1293 	asy->asy_hwtype = asymaxchip; /* just for asy_reset_fifo() */
1294 	if (asymaxchip >= ASY16550A)
1295 		asy->asy_fifor |=
1296 		    FIFO_ON | FIFODMA | (asy_trig_level & 0xff);
1297 	if (asymaxchip >= ASY16650)
1298 		asy->asy_fifor |= FIFOEXTRA1 | FIFOEXTRA2;
1299 
1300 	asy_reset_fifo(asy, FIFOTXFLSH | FIFORXFLSH);
1301 
1302 	mcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
1303 	ret = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + ISR);
1304 	DEBUGCONT4(ASY_DEBUG_CHIP,
1305 	    "asy%d: probe fifo FIFOR=0x%02x ISR=0x%02x MCR=0x%02x\n",
1306 	    asy->asy_unit, asy->asy_fifor | FIFOTXFLSH | FIFORXFLSH,
1307 	    ret, mcr);
1308 	switch (ret & 0xf0) {
1309 	case 0x40:
1310 		hwtype = ASY16550; /* 16550 with broken FIFO */
1311 		asy->asy_fifor = 0;
1312 		break;
1313 	case 0xc0:
1314 		hwtype = ASY16550A;
1315 		asy->asy_fifo_buf = 16;
1316 		asy->asy_use_fifo = FIFO_ON;
1317 		asy->asy_fifor &= ~(FIFOEXTRA1 | FIFOEXTRA2);
1318 		break;
1319 	case 0xe0:
1320 		hwtype = ASY16650;
1321 		asy->asy_fifo_buf = 32;
1322 		asy->asy_use_fifo = FIFO_ON;
1323 		asy->asy_fifor &= ~(FIFOEXTRA1);
1324 		break;
1325 	case 0xf0:
1326 		/*
1327 		 * Note we get 0xff if chip didn't return us anything,
1328 		 * e.g. if there's no chip there.
1329 		 */
1330 		if (ret == 0xff) {
1331 			cmn_err(CE_CONT, "asy%d: UART @ %p "
1332 			    "interrupt register: got 0xff\n",
1333 			    asy->asy_unit, (void *)asy->asy_ioaddr);
1334 			return (DDI_FAILURE);
1335 		}
1336 		/*FALLTHRU*/
1337 	case 0xd0:
1338 		hwtype = ASY16750;
1339 		asy->asy_fifo_buf = 64;
1340 		asy->asy_use_fifo = FIFO_ON;
1341 		break;
1342 	default:
1343 		hwtype = ASY8250A; /* No FIFO */
1344 		asy->asy_fifor = 0;
1345 	}
1346 
1347 	if (hwtype > asymaxchip) {
1348 		cmn_err(CE_CONT, "asy%d: UART @ %p "
1349 		    "unexpected probe result: "
1350 		    "FIFOR=0x%02x ISR=0x%02x MCR=0x%02x\n",
1351 		    asy->asy_unit, (void *)asy->asy_ioaddr,
1352 		    asy->asy_fifor | FIFOTXFLSH | FIFORXFLSH, ret, mcr);
1353 		return (DDI_FAILURE);
1354 	}
1355 
1356 	/*
1357 	 * Now reset the FIFO operation appropriate for the chip type.
1358 	 * Note we must call asy_reset_fifo() before any possible
1359 	 * downgrade of the asy->asy_hwtype, or it may not disable
1360 	 * the more advanced features we specifically want downgraded.
1361 	 */
1362 	asy_reset_fifo(asy, 0);
1363 	asy->asy_hwtype = hwtype;
1364 
1365 	/*
1366 	 * Check for Exar/Startech ST16C650, which will still look like a
1367 	 * 16550A until we enable its enhanced mode.
1368 	 */
1369 	if (asy->asy_hwtype == ASY16550A && asymaxchip >= ASY16650 &&
1370 	    asy_scr_test) {
1371 		/* Enable enhanced mode register access */
1372 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1373 		    EFRACCESS);
1374 		/* zero scratch register (not scratch register if enhanced) */
1375 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + SCR, 0);
1376 		/* Disable enhanced mode register access */
1377 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1378 		    STOP1|BITS8);
1379 		/* read back scratch register */
1380 		ret = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + SCR);
1381 		if (ret == SCRTEST) {
1382 			/* looks like we have an ST16650 -- enable it */
1383 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1384 			    EFRACCESS);
1385 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + EFR,
1386 			    ENHENABLE);
1387 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1388 			    STOP1|BITS8);
1389 			asy->asy_hwtype = ASY16650;
1390 			asy->asy_fifo_buf = 32;
1391 			asy->asy_fifor |= 0x10; /* 24 byte txfifo trigger */
1392 			asy_reset_fifo(asy, 0);
1393 		}
1394 	}
1395 
1396 	/*
1397 	 * If we think we might have a FIFO larger than 16 characters,
1398 	 * measure FIFO size and check it against expected.
1399 	 */
1400 	if (asy_fifo_test > 0 &&
1401 	    !(asy->asy_flags2 & ASY2_NO_LOOPBACK) &&
1402 	    (asy->asy_fifo_buf > 16 ||
1403 	    (asy_fifo_test > 1 && asy->asy_use_fifo == FIFO_ON) ||
1404 	    ASY_DEBUG(ASY_DEBUG_CHIP))) {
1405 		int i;
1406 
1407 		/* Set baud rate to 57600 (fairly arbitrary choice) */
1408 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1409 		    DLAB);
1410 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
1411 		    asyspdtab[B57600] & 0xff);
1412 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR,
1413 		    (asyspdtab[B57600] >> 8) & 0xff);
1414 		/* Set 8 bits, 1 stop bit */
1415 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1416 		    STOP1|BITS8);
1417 		/* Set loopback mode */
1418 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1419 		    DTR | RTS | ASY_LOOP | OUT1 | OUT2);
1420 
1421 		/* Overfill fifo */
1422 		for (i = 0; i < asy->asy_fifo_buf * 2; i++) {
1423 			ddi_put8(asy->asy_iohandle,
1424 			    asy->asy_ioaddr + DAT, i);
1425 		}
1426 		/*
1427 		 * Now there's an interesting question here about which
1428 		 * FIFO we're testing the size of, RX or TX. We just
1429 		 * filled the TX FIFO much faster than it can empty,
1430 		 * although it is possible one or two characters may
1431 		 * have gone from it to the TX shift register.
1432 		 * We wait for enough time for all the characters to
1433 		 * move into the RX FIFO and any excess characters to
1434 		 * have been lost, and then read all the RX FIFO. So
1435 		 * the answer we finally get will be the size which is
1436 		 * the MIN(RX FIFO,(TX FIFO + 1 or 2)). The critical
1437 		 * one is actually the TX FIFO, because if we overfill
1438 		 * it in normal operation, the excess characters are
1439 		 * lost with no warning.
1440 		 */
1441 		/*
1442 		 * Wait for characters to move into RX FIFO.
1443 		 * In theory, 200 * asy->asy_fifo_buf * 2 should be
1444 		 * enough. However, in practice it isn't always, so we
1445 		 * increase to 400 so some slow 16550A's finish, and we
1446 		 * increase to 3 so we spot more characters coming back
1447 		 * than we sent, in case that should ever happen.
1448 		 */
1449 		delay(drv_usectohz(400 * asy->asy_fifo_buf * 3));
1450 
1451 		/* Now see how many characters we can read back */
1452 		for (i = 0; i < asy->asy_fifo_buf * 3; i++) {
1453 			ret = ddi_get8(asy->asy_iohandle,
1454 			    asy->asy_ioaddr + LSR);
1455 			if (!(ret & RCA))
1456 				break;	/* FIFO emptied */
1457 			(void) ddi_get8(asy->asy_iohandle,
1458 			    asy->asy_ioaddr + DAT); /* lose another */
1459 		}
1460 
1461 		DEBUGCONT3(ASY_DEBUG_CHIP,
1462 		    "asy%d FIFO size: expected=%d, measured=%d\n",
1463 		    asy->asy_unit, asy->asy_fifo_buf, i);
1464 
1465 		hwtype = asy->asy_hwtype;
1466 		if (i < asy->asy_fifo_buf) {
1467 			/*
1468 			 * FIFO is somewhat smaller than we anticipated.
1469 			 * If we have 16 characters usable, then this
1470 			 * UART will probably work well enough in
1471 			 * 16550A mode. If less than 16 characters,
1472 			 * then we'd better not use it at all.
1473 			 * UARTs with busted FIFOs do crop up.
1474 			 */
1475 			if (i >= 16 && asy->asy_fifo_buf >= 16) {
1476 				/* fall back to a 16550A */
1477 				hwtype = ASY16550A;
1478 				asy->asy_fifo_buf = 16;
1479 				asy->asy_fifor &= ~(FIFOEXTRA1 | FIFOEXTRA2);
1480 			} else {
1481 				/* fall back to no FIFO at all */
1482 				hwtype = ASY16550;
1483 				asy->asy_fifo_buf = 1;
1484 				asy->asy_use_fifo = FIFO_OFF;
1485 				asy->asy_fifor &=
1486 				    ~(FIFO_ON | FIFOEXTRA1 | FIFOEXTRA2);
1487 			}
1488 		}
1489 		/*
1490 		 * We will need to reprogram the FIFO if we changed
1491 		 * our mind about how to drive it above, and in any
1492 		 * case, it would be a good idea to flush any garbage
1493 		 * out incase the loopback test left anything behind.
1494 		 * Again as earlier above, we must call asy_reset_fifo()
1495 		 * before any possible downgrade of asy->asy_hwtype.
1496 		 */
1497 		if (asy->asy_hwtype >= ASY16650 && hwtype < ASY16650) {
1498 			/* Disable 16650 enhanced mode */
1499 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1500 			    EFRACCESS);
1501 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + EFR,
1502 			    0);
1503 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1504 			    STOP1|BITS8);
1505 		}
1506 		asy_reset_fifo(asy, FIFOTXFLSH | FIFORXFLSH);
1507 		asy->asy_hwtype = hwtype;
1508 
1509 		/* Clear loopback mode and restore DTR/RTS */
1510 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR, mcr);
1511 	}
1512 
1513 	DEBUGNOTE3(ASY_DEBUG_CHIP, "asy%d %s @ %p",
1514 	    asy->asy_unit, asy_hw_name(asy), (void *)asy->asy_ioaddr);
1515 
1516 	/* Make UART type visible in device tree for prtconf, etc */
1517 	dev = makedevice(DDI_MAJOR_T_UNKNOWN, asy->asy_unit);
1518 	(void) ddi_prop_update_string(dev, devi, "uart", asy_hw_name(asy));
1519 
1520 	if (asy->asy_hwtype == ASY16550)	/* for broken 16550's, */
1521 		asy->asy_hwtype = ASY8250A;	/* drive them as 8250A */
1522 
1523 	return (DDI_SUCCESS);
1524 }
1525 
1526 /*
1527  * asyinit() initializes the TTY protocol-private data for this channel
1528  * before enabling the interrupts.
1529  */
1530 static void
1531 asyinit(struct asycom *asy)
1532 {
1533 	struct asyncline *async;
1534 
1535 	asy->asy_priv = kmem_zalloc(sizeof (struct asyncline), KM_SLEEP);
1536 	async = asy->asy_priv;
1537 	mutex_enter(&asy->asy_excl);
1538 	async->async_common = asy;
1539 	cv_init(&async->async_flags_cv, NULL, CV_DRIVER, NULL);
1540 	mutex_exit(&asy->asy_excl);
1541 }
1542 
1543 /*ARGSUSED3*/
1544 static int
1545 asyopen(queue_t *rq, dev_t *dev, int flag, int sflag, cred_t *cr)
1546 {
1547 	struct asycom	*asy;
1548 	struct asyncline *async;
1549 	int		mcr;
1550 	int		unit;
1551 	int 		len;
1552 	struct termios 	*termiosp;
1553 
1554 	unit = UNIT(*dev);
1555 	DEBUGCONT1(ASY_DEBUG_CLOSE, "asy%dopen\n", unit);
1556 	asy = ddi_get_soft_state(asy_soft_state, unit);
1557 	if (asy == NULL)
1558 		return (ENXIO);		/* unit not configured */
1559 	async = asy->asy_priv;
1560 	mutex_enter(&asy->asy_excl);
1561 
1562 again:
1563 	mutex_enter(&asy->asy_excl_hi);
1564 
1565 	/*
1566 	 * Block waiting for carrier to come up, unless this is a no-delay open.
1567 	 */
1568 	if (!(async->async_flags & ASYNC_ISOPEN)) {
1569 		/*
1570 		 * Set the default termios settings (cflag).
1571 		 * Others are set in ldterm.
1572 		 */
1573 		mutex_exit(&asy->asy_excl_hi);
1574 
1575 		if (ddi_getlongprop(DDI_DEV_T_ANY, ddi_root_node(),
1576 		    0, "ttymodes",
1577 		    (caddr_t)&termiosp, &len) == DDI_PROP_SUCCESS &&
1578 		    len == sizeof (struct termios)) {
1579 			async->async_ttycommon.t_cflag = termiosp->c_cflag;
1580 			kmem_free(termiosp, len);
1581 		} else
1582 			cmn_err(CE_WARN,
1583 			    "asy: couldn't get ttymodes property!");
1584 		mutex_enter(&asy->asy_excl_hi);
1585 
1586 		/* eeprom mode support - respect properties */
1587 		if (asy->asy_cflag)
1588 			async->async_ttycommon.t_cflag = asy->asy_cflag;
1589 
1590 		async->async_ttycommon.t_iflag = 0;
1591 		async->async_ttycommon.t_iocpending = NULL;
1592 		async->async_ttycommon.t_size.ws_row = 0;
1593 		async->async_ttycommon.t_size.ws_col = 0;
1594 		async->async_ttycommon.t_size.ws_xpixel = 0;
1595 		async->async_ttycommon.t_size.ws_ypixel = 0;
1596 		async->async_dev = *dev;
1597 		async->async_wbufcid = 0;
1598 
1599 		async->async_startc = CSTART;
1600 		async->async_stopc = CSTOP;
1601 		asy_program(asy, ASY_INIT);
1602 	} else
1603 		if ((async->async_ttycommon.t_flags & TS_XCLUDE) &&
1604 		    secpolicy_excl_open(cr) != 0) {
1605 		mutex_exit(&asy->asy_excl_hi);
1606 		mutex_exit(&asy->asy_excl);
1607 		return (EBUSY);
1608 	} else if ((*dev & OUTLINE) && !(async->async_flags & ASYNC_OUT)) {
1609 		mutex_exit(&asy->asy_excl_hi);
1610 		mutex_exit(&asy->asy_excl);
1611 		return (EBUSY);
1612 	}
1613 
1614 	if (*dev & OUTLINE)
1615 		async->async_flags |= ASYNC_OUT;
1616 
1617 	/* Raise DTR on every open, but delay if it was just lowered. */
1618 	while (async->async_flags & ASYNC_DTR_DELAY) {
1619 		DEBUGCONT1(ASY_DEBUG_MODEM,
1620 		    "asy%dopen: waiting for the ASYNC_DTR_DELAY to be clear\n",
1621 		    unit);
1622 		mutex_exit(&asy->asy_excl_hi);
1623 		if (cv_wait_sig(&async->async_flags_cv,
1624 		    &asy->asy_excl) == 0) {
1625 			DEBUGCONT1(ASY_DEBUG_MODEM,
1626 			    "asy%dopen: interrupted by signal, exiting\n",
1627 			    unit);
1628 			mutex_exit(&asy->asy_excl);
1629 			return (EINTR);
1630 		}
1631 		mutex_enter(&asy->asy_excl_hi);
1632 	}
1633 
1634 	mcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
1635 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1636 	    mcr|(asy->asy_mcr&DTR));
1637 
1638 	DEBUGCONT3(ASY_DEBUG_INIT,
1639 	    "asy%dopen: \"Raise DTR on every open\": make mcr = %x, "
1640 	    "make TS_SOFTCAR = %s\n",
1641 	    unit, mcr|(asy->asy_mcr&DTR),
1642 	    (asy->asy_flags & ASY_IGNORE_CD) ? "ON" : "OFF");
1643 
1644 	if (asy->asy_flags & ASY_IGNORE_CD) {
1645 		DEBUGCONT1(ASY_DEBUG_MODEM,
1646 		    "asy%dopen: ASY_IGNORE_CD set, set TS_SOFTCAR\n",
1647 		    unit);
1648 		async->async_ttycommon.t_flags |= TS_SOFTCAR;
1649 	}
1650 	else
1651 		async->async_ttycommon.t_flags &= ~TS_SOFTCAR;
1652 
1653 	/*
1654 	 * Check carrier.
1655 	 */
1656 	asy->asy_msr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MSR);
1657 	DEBUGCONT3(ASY_DEBUG_INIT, "asy%dopen: TS_SOFTCAR is %s, "
1658 	    "MSR & DCD is %s\n",
1659 	    unit,
1660 	    (async->async_ttycommon.t_flags & TS_SOFTCAR) ? "set" : "clear",
1661 	    (asy->asy_msr & DCD) ? "set" : "clear");
1662 
1663 	if (asy->asy_msr & DCD)
1664 		async->async_flags |= ASYNC_CARR_ON;
1665 	else
1666 		async->async_flags &= ~ASYNC_CARR_ON;
1667 	mutex_exit(&asy->asy_excl_hi);
1668 
1669 	/*
1670 	 * If FNDELAY and FNONBLOCK are clear, block until carrier up.
1671 	 * Quit on interrupt.
1672 	 */
1673 	if (!(flag & (FNDELAY|FNONBLOCK)) &&
1674 	    !(async->async_ttycommon.t_cflag & CLOCAL)) {
1675 		if ((!(async->async_flags & (ASYNC_CARR_ON|ASYNC_OUT)) &&
1676 		    !(async->async_ttycommon.t_flags & TS_SOFTCAR)) ||
1677 		    ((async->async_flags & ASYNC_OUT) &&
1678 		    !(*dev & OUTLINE))) {
1679 			async->async_flags |= ASYNC_WOPEN;
1680 			if (cv_wait_sig(&async->async_flags_cv,
1681 			    &asy->asy_excl) == B_FALSE) {
1682 				async->async_flags &= ~ASYNC_WOPEN;
1683 				mutex_exit(&asy->asy_excl);
1684 				return (EINTR);
1685 			}
1686 			async->async_flags &= ~ASYNC_WOPEN;
1687 			goto again;
1688 		}
1689 	} else if ((async->async_flags & ASYNC_OUT) && !(*dev & OUTLINE)) {
1690 		mutex_exit(&asy->asy_excl);
1691 		return (EBUSY);
1692 	}
1693 
1694 	async->async_ttycommon.t_readq = rq;
1695 	async->async_ttycommon.t_writeq = WR(rq);
1696 	rq->q_ptr = WR(rq)->q_ptr = (caddr_t)async;
1697 	mutex_exit(&asy->asy_excl);
1698 	/*
1699 	 * Caution here -- qprocson sets the pointers that are used by canput
1700 	 * called by async_softint.  ASYNC_ISOPEN must *not* be set until those
1701 	 * pointers are valid.
1702 	 */
1703 	qprocson(rq);
1704 	async->async_flags |= ASYNC_ISOPEN;
1705 	async->async_polltid = 0;
1706 	DEBUGCONT1(ASY_DEBUG_INIT, "asy%dopen: done\n", unit);
1707 	return (0);
1708 }
1709 
1710 static void
1711 async_progress_check(void *arg)
1712 {
1713 	struct asyncline *async = arg;
1714 	struct asycom	 *asy = async->async_common;
1715 	mblk_t *bp;
1716 
1717 	/*
1718 	 * We define "progress" as either waiting on a timed break or delay, or
1719 	 * having had at least one transmitter interrupt.  If none of these are
1720 	 * true, then just terminate the output and wake up that close thread.
1721 	 */
1722 	mutex_enter(&asy->asy_excl);
1723 	mutex_enter(&asy->asy_excl_hi);
1724 	if (!(async->async_flags & (ASYNC_BREAK|ASYNC_DELAY|ASYNC_PROGRESS))) {
1725 		async->async_ocnt = 0;
1726 		async->async_flags &= ~ASYNC_BUSY;
1727 		async->async_timer = 0;
1728 		bp = async->async_xmitblk;
1729 		async->async_xmitblk = NULL;
1730 		mutex_exit(&asy->asy_excl_hi);
1731 		if (bp != NULL)
1732 			freeb(bp);
1733 		/*
1734 		 * Since this timer is running, we know that we're in exit(2).
1735 		 * That means that the user can't possibly be waiting on any
1736 		 * valid ioctl(2) completion anymore, and we should just flush
1737 		 * everything.
1738 		 */
1739 		flushq(async->async_ttycommon.t_writeq, FLUSHALL);
1740 		cv_broadcast(&async->async_flags_cv);
1741 	} else {
1742 		async->async_flags &= ~ASYNC_PROGRESS;
1743 		async->async_timer = timeout(async_progress_check, async,
1744 		    drv_usectohz(asy_drain_check));
1745 		mutex_exit(&asy->asy_excl_hi);
1746 	}
1747 	mutex_exit(&asy->asy_excl);
1748 }
1749 
1750 /*
1751  * Release DTR so that asyopen() can raise it.
1752  */
1753 static void
1754 async_dtr_free(struct asyncline *async)
1755 {
1756 	struct asycom *asy = async->async_common;
1757 
1758 	DEBUGCONT0(ASY_DEBUG_MODEM,
1759 	    "async_dtr_free, clearing ASYNC_DTR_DELAY\n");
1760 	mutex_enter(&asy->asy_excl);
1761 	async->async_flags &= ~ASYNC_DTR_DELAY;
1762 	async->async_dtrtid = 0;
1763 	cv_broadcast(&async->async_flags_cv);
1764 	mutex_exit(&asy->asy_excl);
1765 }
1766 
1767 /*
1768  * Close routine.
1769  */
1770 /*ARGSUSED2*/
1771 static int
1772 asyclose(queue_t *q, int flag, cred_t *credp)
1773 {
1774 	struct asyncline *async;
1775 	struct asycom	 *asy;
1776 	int icr, lcr;
1777 #ifdef DEBUG
1778 	int instance;
1779 #endif
1780 
1781 	async = (struct asyncline *)q->q_ptr;
1782 	ASSERT(async != NULL);
1783 #ifdef DEBUG
1784 	instance = UNIT(async->async_dev);
1785 	DEBUGCONT1(ASY_DEBUG_CLOSE, "asy%dclose\n", instance);
1786 #endif
1787 	asy = async->async_common;
1788 
1789 	mutex_enter(&asy->asy_excl);
1790 	async->async_flags |= ASYNC_CLOSING;
1791 
1792 	/*
1793 	 * Turn off PPS handling early to avoid events occuring during
1794 	 * close.  Also reset the DCD edge monitoring bit.
1795 	 */
1796 	mutex_enter(&asy->asy_excl_hi);
1797 	asy->asy_flags &= ~(ASY_PPS | ASY_PPS_EDGE);
1798 	mutex_exit(&asy->asy_excl_hi);
1799 
1800 	/*
1801 	 * There are two flavors of break -- timed (M_BREAK or TCSBRK) and
1802 	 * untimed (TIOCSBRK).  For the timed case, these are enqueued on our
1803 	 * write queue and there's a timer running, so we don't have to worry
1804 	 * about them.  For the untimed case, though, the user obviously made a
1805 	 * mistake, because these are handled immediately.  We'll terminate the
1806 	 * break now and honor his implicit request by discarding the rest of
1807 	 * the data.
1808 	 */
1809 	if (async->async_flags & ASYNC_OUT_SUSPEND) {
1810 		if (async->async_utbrktid != 0) {
1811 			(void) untimeout(async->async_utbrktid);
1812 			async->async_utbrktid = 0;
1813 		}
1814 		mutex_enter(&asy->asy_excl_hi);
1815 		lcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
1816 		ddi_put8(asy->asy_iohandle,
1817 		    asy->asy_ioaddr + LCR, (lcr & ~SETBREAK));
1818 		mutex_exit(&asy->asy_excl_hi);
1819 		async->async_flags &= ~ASYNC_OUT_SUSPEND;
1820 		goto nodrain;
1821 	}
1822 
1823 	/*
1824 	 * If the user told us not to delay the close ("non-blocking"), then
1825 	 * don't bother trying to drain.
1826 	 *
1827 	 * If the user did M_STOP (ASYNC_STOPPED), there's no hope of ever
1828 	 * getting an M_START (since these messages aren't enqueued), and the
1829 	 * only other way to clear the stop condition is by loss of DCD, which
1830 	 * would discard the queue data.  Thus, we drop the output data if
1831 	 * ASYNC_STOPPED is set.
1832 	 */
1833 	if ((flag & (FNDELAY|FNONBLOCK)) ||
1834 	    (async->async_flags & ASYNC_STOPPED)) {
1835 		goto nodrain;
1836 	}
1837 
1838 	/*
1839 	 * If there's any pending output, then we have to try to drain it.
1840 	 * There are two main cases to be handled:
1841 	 *	- called by close(2): need to drain until done or until
1842 	 *	  a signal is received.  No timeout.
1843 	 *	- called by exit(2): need to drain while making progress
1844 	 *	  or until a timeout occurs.  No signals.
1845 	 *
1846 	 * If we can't rely on receiving a signal to get us out of a hung
1847 	 * session, then we have to use a timer.  In this case, we set a timer
1848 	 * to check for progress in sending the output data -- all that we ask
1849 	 * (at each interval) is that there's been some progress made.  Since
1850 	 * the interrupt routine grabs buffers from the write queue, we can't
1851 	 * trust changes in async_ocnt.  Instead, we use a progress flag.
1852 	 *
1853 	 * Note that loss of carrier will cause the output queue to be flushed,
1854 	 * and we'll wake up again and finish normally.
1855 	 */
1856 	if (!ddi_can_receive_sig() && asy_drain_check != 0) {
1857 		async->async_flags &= ~ASYNC_PROGRESS;
1858 		async->async_timer = timeout(async_progress_check, async,
1859 		    drv_usectohz(asy_drain_check));
1860 	}
1861 	while (async->async_ocnt > 0 ||
1862 	    async->async_ttycommon.t_writeq->q_first != NULL ||
1863 	    (async->async_flags & (ASYNC_BUSY|ASYNC_BREAK|ASYNC_DELAY))) {
1864 		if (cv_wait_sig(&async->async_flags_cv, &asy->asy_excl) == 0)
1865 			break;
1866 	}
1867 	if (async->async_timer != 0) {
1868 		(void) untimeout(async->async_timer);
1869 		async->async_timer = 0;
1870 	}
1871 
1872 nodrain:
1873 	async->async_ocnt = 0;
1874 	if (async->async_xmitblk != NULL)
1875 		freeb(async->async_xmitblk);
1876 	async->async_xmitblk = NULL;
1877 
1878 	/*
1879 	 * If line has HUPCL set or is incompletely opened fix up the modem
1880 	 * lines.
1881 	 */
1882 	DEBUGCONT1(ASY_DEBUG_MODEM, "asy%dclose: next check HUPCL flag\n",
1883 	    instance);
1884 	mutex_enter(&asy->asy_excl_hi);
1885 	if ((async->async_ttycommon.t_cflag & HUPCL) ||
1886 	    (async->async_flags & ASYNC_WOPEN)) {
1887 		DEBUGCONT3(ASY_DEBUG_MODEM,
1888 		    "asy%dclose: HUPCL flag = %x, ASYNC_WOPEN flag = %x\n",
1889 		    instance,
1890 		    async->async_ttycommon.t_cflag & HUPCL,
1891 		    async->async_ttycommon.t_cflag & ASYNC_WOPEN);
1892 		async->async_flags |= ASYNC_DTR_DELAY;
1893 
1894 		/* turn off DTR, RTS but NOT interrupt to 386 */
1895 		if (asy->asy_flags & (ASY_IGNORE_CD|ASY_RTS_DTR_OFF)) {
1896 			DEBUGCONT3(ASY_DEBUG_MODEM,
1897 			    "asy%dclose: ASY_IGNORE_CD flag = %x, "
1898 			    "ASY_RTS_DTR_OFF flag = %x\n",
1899 			    instance,
1900 			    asy->asy_flags & ASY_IGNORE_CD,
1901 			    asy->asy_flags & ASY_RTS_DTR_OFF);
1902 
1903 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1904 			    asy->asy_mcr|OUT2);
1905 		} else {
1906 			DEBUGCONT1(ASY_DEBUG_MODEM,
1907 			    "asy%dclose: Dropping DTR and RTS\n", instance);
1908 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1909 			    OUT2);
1910 		}
1911 		async->async_dtrtid =
1912 		    timeout((void (*)())async_dtr_free,
1913 		    (caddr_t)async, drv_usectohz(asy_min_dtr_low));
1914 	}
1915 	/*
1916 	 * If nobody's using it now, turn off receiver interrupts.
1917 	 */
1918 	if ((async->async_flags & (ASYNC_WOPEN|ASYNC_ISOPEN)) == 0) {
1919 		icr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + ICR);
1920 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR,
1921 		    (icr & ~RIEN));
1922 	}
1923 	mutex_exit(&asy->asy_excl_hi);
1924 out:
1925 	ttycommon_close(&async->async_ttycommon);
1926 
1927 	/*
1928 	 * Cancel outstanding "bufcall" request.
1929 	 */
1930 	if (async->async_wbufcid != 0) {
1931 		unbufcall(async->async_wbufcid);
1932 		async->async_wbufcid = 0;
1933 	}
1934 
1935 	/* Note that qprocsoff can't be done until after interrupts are off */
1936 	qprocsoff(q);
1937 	q->q_ptr = WR(q)->q_ptr = NULL;
1938 	async->async_ttycommon.t_readq = NULL;
1939 	async->async_ttycommon.t_writeq = NULL;
1940 
1941 	/*
1942 	 * Clear out device state, except persistant device property flags.
1943 	 */
1944 	async->async_flags &= (ASYNC_DTR_DELAY|ASY_RTS_DTR_OFF);
1945 	cv_broadcast(&async->async_flags_cv);
1946 	mutex_exit(&asy->asy_excl);
1947 
1948 	DEBUGCONT1(ASY_DEBUG_CLOSE, "asy%dclose: done\n", instance);
1949 	return (0);
1950 }
1951 
1952 static boolean_t
1953 asy_isbusy(struct asycom *asy)
1954 {
1955 	struct asyncline *async;
1956 
1957 	DEBUGCONT0(ASY_DEBUG_EOT, "asy_isbusy\n");
1958 	async = asy->asy_priv;
1959 	ASSERT(mutex_owned(&asy->asy_excl));
1960 	ASSERT(mutex_owned(&asy->asy_excl_hi));
1961 /*
1962  * XXXX this should be recoded
1963  */
1964 	return ((async->async_ocnt > 0) ||
1965 	    ((ddi_get8(asy->asy_iohandle,
1966 	    asy->asy_ioaddr + LSR) & (XSRE|XHRE)) == 0));
1967 }
1968 
1969 static void
1970 asy_waiteot(struct asycom *asy)
1971 {
1972 	/*
1973 	 * Wait for the current transmission block and the
1974 	 * current fifo data to transmit. Once this is done
1975 	 * we may go on.
1976 	 */
1977 	DEBUGCONT0(ASY_DEBUG_EOT, "asy_waiteot\n");
1978 	ASSERT(mutex_owned(&asy->asy_excl));
1979 	ASSERT(mutex_owned(&asy->asy_excl_hi));
1980 	while (asy_isbusy(asy)) {
1981 		mutex_exit(&asy->asy_excl_hi);
1982 		mutex_exit(&asy->asy_excl);
1983 		drv_usecwait(10000);		/* wait .01 */
1984 		mutex_enter(&asy->asy_excl);
1985 		mutex_enter(&asy->asy_excl_hi);
1986 	}
1987 }
1988 
1989 /* asy_reset_fifo -- flush fifos and [re]program fifo control register */
1990 static void
1991 asy_reset_fifo(struct asycom *asy, uchar_t flush)
1992 {
1993 	uchar_t lcr;
1994 
1995 	/* On a 16750, we have to set DLAB in order to set FIFOEXTRA. */
1996 
1997 	if (asy->asy_hwtype >= ASY16750) {
1998 		lcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
1999 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
2000 		    lcr | DLAB);
2001 	}
2002 
2003 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + FIFOR,
2004 	    asy->asy_fifor | flush);
2005 
2006 	/* Clear DLAB */
2007 
2008 	if (asy->asy_hwtype >= ASY16750) {
2009 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, lcr);
2010 	}
2011 }
2012 
2013 /*
2014  * Program the ASY port. Most of the async operation is based on the values
2015  * of 'c_iflag' and 'c_cflag'.
2016  */
2017 
2018 #define	BAUDINDEX(cflg)	(((cflg) & CBAUDEXT) ? \
2019 			(((cflg) & CBAUD) + CBAUD + 1) : ((cflg) & CBAUD))
2020 
2021 static void
2022 asy_program(struct asycom *asy, int mode)
2023 {
2024 	struct asyncline *async;
2025 	int baudrate, c_flag;
2026 	int icr, lcr;
2027 	int flush_reg;
2028 	int ocflags;
2029 #ifdef DEBUG
2030 	int instance;
2031 #endif
2032 
2033 	ASSERT(mutex_owned(&asy->asy_excl));
2034 	ASSERT(mutex_owned(&asy->asy_excl_hi));
2035 
2036 	async = asy->asy_priv;
2037 #ifdef DEBUG
2038 	instance = UNIT(async->async_dev);
2039 	DEBUGCONT2(ASY_DEBUG_PROCS,
2040 	    "asy%d_program: mode = 0x%08X, enter\n", instance, mode);
2041 #endif
2042 
2043 	baudrate = BAUDINDEX(async->async_ttycommon.t_cflag);
2044 
2045 	async->async_ttycommon.t_cflag &= ~(CIBAUD);
2046 
2047 	if (baudrate > CBAUD) {
2048 		async->async_ttycommon.t_cflag |= CIBAUDEXT;
2049 		async->async_ttycommon.t_cflag |=
2050 		    (((baudrate - CBAUD - 1) << IBSHIFT) & CIBAUD);
2051 	} else {
2052 		async->async_ttycommon.t_cflag &= ~CIBAUDEXT;
2053 		async->async_ttycommon.t_cflag |=
2054 		    ((baudrate << IBSHIFT) & CIBAUD);
2055 	}
2056 
2057 	c_flag = async->async_ttycommon.t_cflag &
2058 	    (CLOCAL|CREAD|CSTOPB|CSIZE|PARENB|PARODD|CBAUD|CBAUDEXT);
2059 
2060 	/* disable interrupts */
2061 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
2062 
2063 	ocflags = asy->asy_ocflag;
2064 
2065 	/* flush/reset the status registers */
2066 	(void) ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + ISR);
2067 	(void) ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR);
2068 	asy->asy_msr = flush_reg = ddi_get8(asy->asy_iohandle,
2069 	    asy->asy_ioaddr + MSR);
2070 	/*
2071 	 * The device is programmed in the open sequence, if we
2072 	 * have to hardware handshake, then this is a good time
2073 	 * to check if the device can receive any data.
2074 	 */
2075 
2076 	if ((CRTSCTS & async->async_ttycommon.t_cflag) && !(flush_reg & CTS)) {
2077 		async_flowcontrol_hw_output(asy, FLOW_STOP);
2078 	} else {
2079 		/*
2080 		 * We can not use async_flowcontrol_hw_output(asy, FLOW_START)
2081 		 * here, because if CRTSCTS is clear, we need clear
2082 		 * ASYNC_HW_OUT_FLW bit.
2083 		 */
2084 		async->async_flags &= ~ASYNC_HW_OUT_FLW;
2085 	}
2086 
2087 	/*
2088 	 * If IXON is not set, clear ASYNC_SW_OUT_FLW;
2089 	 * If IXON is set, no matter what IXON flag is before this
2090 	 * function call to asy_program,
2091 	 * we will use the old ASYNC_SW_OUT_FLW status.
2092 	 * Because of handling IXON in the driver, we also should re-calculate
2093 	 * the value of ASYNC_OUT_FLW_RESUME bit, but in fact,
2094 	 * the TCSET* commands which call asy_program
2095 	 * are put into the write queue, so there is no output needed to
2096 	 * be resumed at this point.
2097 	 */
2098 	if (!(IXON & async->async_ttycommon.t_iflag))
2099 		async->async_flags &= ~ASYNC_SW_OUT_FLW;
2100 
2101 	/* manually flush receive buffer or fifo (workaround for buggy fifos) */
2102 	if (mode == ASY_INIT)
2103 		if (asy->asy_use_fifo == FIFO_ON) {
2104 			for (flush_reg = asy->asy_fifo_buf; flush_reg-- > 0; ) {
2105 				(void) ddi_get8(asy->asy_iohandle,
2106 				    asy->asy_ioaddr + DAT);
2107 			}
2108 		} else {
2109 			flush_reg = ddi_get8(asy->asy_iohandle,
2110 			    asy->asy_ioaddr + DAT);
2111 		}
2112 
2113 	if (ocflags != (c_flag & ~CLOCAL) || mode == ASY_INIT) {
2114 		/* Set line control */
2115 		lcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
2116 		lcr &= ~(WLS0|WLS1|STB|PEN|EPS);
2117 
2118 		if (c_flag & CSTOPB)
2119 			lcr |= STB;	/* 2 stop bits */
2120 
2121 		if (c_flag & PARENB)
2122 			lcr |= PEN;
2123 
2124 		if ((c_flag & PARODD) == 0)
2125 			lcr |= EPS;
2126 
2127 		switch (c_flag & CSIZE) {
2128 		case CS5:
2129 			lcr |= BITS5;
2130 			break;
2131 		case CS6:
2132 			lcr |= BITS6;
2133 			break;
2134 		case CS7:
2135 			lcr |= BITS7;
2136 			break;
2137 		case CS8:
2138 			lcr |= BITS8;
2139 			break;
2140 		}
2141 
2142 		/* set the baud rate, unless it is "0" */
2143 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, DLAB);
2144 
2145 		if (baudrate != 0) {
2146 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
2147 			    asyspdtab[baudrate] & 0xff);
2148 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR,
2149 			    (asyspdtab[baudrate] >> 8) & 0xff);
2150 		}
2151 		/* set the line control modes */
2152 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, lcr);
2153 
2154 		/*
2155 		 * If we have a FIFO buffer, enable/flush
2156 		 * at intialize time, flush if transitioning from
2157 		 * CREAD off to CREAD on.
2158 		 */
2159 		if ((ocflags & CREAD) == 0 && (c_flag & CREAD) ||
2160 		    mode == ASY_INIT)
2161 			if (asy->asy_use_fifo == FIFO_ON)
2162 				asy_reset_fifo(asy, FIFORXFLSH);
2163 
2164 		/* remember the new cflags */
2165 		asy->asy_ocflag = c_flag & ~CLOCAL;
2166 	}
2167 
2168 	if (baudrate == 0)
2169 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
2170 		    (asy->asy_mcr & RTS) | OUT2);
2171 	else
2172 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
2173 		    asy->asy_mcr | OUT2);
2174 
2175 	/*
2176 	 * Call the modem status interrupt handler to check for the carrier
2177 	 * in case CLOCAL was turned off after the carrier came on.
2178 	 * (Note: Modem status interrupt is not enabled if CLOCAL is ON.)
2179 	 */
2180 	async_msint(asy);
2181 
2182 	/* Set interrupt control */
2183 	DEBUGCONT3(ASY_DEBUG_MODM2,
2184 	    "asy%d_program: c_flag & CLOCAL = %x t_cflag & CRTSCTS = %x\n",
2185 	    instance, c_flag & CLOCAL,
2186 	    async->async_ttycommon.t_cflag & CRTSCTS);
2187 
2188 	if ((c_flag & CLOCAL) && !(async->async_ttycommon.t_cflag & CRTSCTS))
2189 		/*
2190 		 * direct-wired line ignores DCD, so we don't enable modem
2191 		 * status interrupts.
2192 		 */
2193 		icr = (TIEN | SIEN);
2194 	else
2195 		icr = (TIEN | SIEN | MIEN);
2196 
2197 	if (c_flag & CREAD)
2198 		icr |= RIEN;
2199 
2200 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, icr);
2201 	DEBUGCONT1(ASY_DEBUG_PROCS, "asy%d_program: done\n", instance);
2202 }
2203 
2204 static boolean_t
2205 asy_baudok(struct asycom *asy)
2206 {
2207 	struct asyncline *async = asy->asy_priv;
2208 	int baudrate;
2209 
2210 
2211 	baudrate = BAUDINDEX(async->async_ttycommon.t_cflag);
2212 
2213 	if (baudrate >= sizeof (asyspdtab)/sizeof (*asyspdtab))
2214 		return (0);
2215 
2216 	return (baudrate == 0 || asyspdtab[baudrate]);
2217 }
2218 
2219 /*
2220  * asyintr() is the High Level Interrupt Handler.
2221  *
2222  * There are four different interrupt types indexed by ISR register values:
2223  *		0: modem
2224  *		1: Tx holding register is empty, ready for next char
2225  *		2: Rx register now holds a char to be picked up
2226  *		3: error or break on line
2227  * This routine checks the Bit 0 (interrupt-not-pending) to determine if
2228  * the interrupt is from this port.
2229  */
2230 uint_t
2231 asyintr(caddr_t argasy)
2232 {
2233 	struct asycom		*asy = (struct asycom *)argasy;
2234 	struct asyncline	*async;
2235 	int			ret_status = DDI_INTR_UNCLAIMED;
2236 	uchar_t			interrupt_id, lsr;
2237 
2238 	interrupt_id = ddi_get8(asy->asy_iohandle,
2239 	    asy->asy_ioaddr + ISR) & 0x0F;
2240 	async = asy->asy_priv;
2241 
2242 	if ((async == NULL) ||
2243 	    !(async->async_flags & (ASYNC_ISOPEN|ASYNC_WOPEN))) {
2244 		if (interrupt_id & NOINTERRUPT)
2245 			return (DDI_INTR_UNCLAIMED);
2246 		else {
2247 			/*
2248 			 * reset the device by:
2249 			 *	reading line status
2250 			 *	reading any data from data status register
2251 			 *	reading modem status
2252 			 */
2253 			(void) ddi_get8(asy->asy_iohandle,
2254 			    asy->asy_ioaddr + LSR);
2255 			(void) ddi_get8(asy->asy_iohandle,
2256 			    asy->asy_ioaddr + DAT);
2257 			asy->asy_msr = ddi_get8(asy->asy_iohandle,
2258 			    asy->asy_ioaddr + MSR);
2259 			return (DDI_INTR_CLAIMED);
2260 		}
2261 	}
2262 
2263 	mutex_enter(&asy->asy_excl_hi);
2264 
2265 	if (asy->asy_flags & ASY_DDI_SUSPENDED) {
2266 		mutex_exit(&asy->asy_excl_hi);
2267 		return (DDI_INTR_CLAIMED);
2268 	}
2269 
2270 	/*
2271 	 * We will loop until the interrupt line is pulled low. asy
2272 	 * interrupt is edge triggered.
2273 	 */
2274 	/* CSTYLED */
2275 	for (;; interrupt_id =
2276 	    (ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + ISR) & 0x0F)) {
2277 
2278 		if (interrupt_id & NOINTERRUPT)
2279 			break;
2280 		ret_status = DDI_INTR_CLAIMED;
2281 
2282 		DEBUGCONT1(ASY_DEBUG_INTR, "asyintr: interrupt_id = 0x%d\n",
2283 		    interrupt_id);
2284 		lsr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR);
2285 		switch (interrupt_id) {
2286 		case RxRDY:
2287 		case RSTATUS:
2288 		case FFTMOUT:
2289 			/* receiver interrupt or receiver errors */
2290 			async_rxint(asy, lsr);
2291 			break;
2292 		case TxRDY:
2293 			/* transmit interrupt */
2294 			async_txint(asy);
2295 			continue;
2296 		case MSTATUS:
2297 			/* modem status interrupt */
2298 			async_msint(asy);
2299 			break;
2300 		}
2301 		if ((lsr & XHRE) && (async->async_flags & ASYNC_BUSY) &&
2302 		    (async->async_ocnt > 0))
2303 			async_txint(asy);
2304 	}
2305 	mutex_exit(&asy->asy_excl_hi);
2306 	return (ret_status);
2307 }
2308 
2309 /*
2310  * Transmitter interrupt service routine.
2311  * If there is more data to transmit in the current pseudo-DMA block,
2312  * send the next character if output is not stopped or draining.
2313  * Otherwise, queue up a soft interrupt.
2314  *
2315  * XXX -  Needs review for HW FIFOs.
2316  */
2317 static void
2318 async_txint(struct asycom *asy)
2319 {
2320 	struct asyncline *async = asy->asy_priv;
2321 	int		fifo_len;
2322 
2323 	ASSERT(MUTEX_HELD(&asy->asy_excl_hi));
2324 
2325 	/*
2326 	 * If ASYNC_BREAK or ASYNC_OUT_SUSPEND has been set, return to
2327 	 * asyintr()'s context to claim the interrupt without performing
2328 	 * any action. No character will be loaded into FIFO/THR until
2329 	 * timed or untimed break is removed
2330 	 */
2331 	if (async->async_flags & (ASYNC_BREAK|ASYNC_OUT_SUSPEND))
2332 		return;
2333 
2334 	fifo_len = asy->asy_fifo_buf; /* with FIFO buffers */
2335 	if (fifo_len > asy_max_tx_fifo)
2336 		fifo_len = asy_max_tx_fifo;
2337 
2338 	if (async_flowcontrol_sw_input(asy, FLOW_CHECK, IN_FLOW_NULL))
2339 		fifo_len--;
2340 
2341 	if (async->async_ocnt > 0 && fifo_len > 0 &&
2342 	    !(async->async_flags &
2343 	    (ASYNC_HW_OUT_FLW|ASYNC_SW_OUT_FLW|ASYNC_STOPPED))) {
2344 		while (fifo_len-- > 0 && async->async_ocnt-- > 0) {
2345 			ddi_put8(asy->asy_iohandle,
2346 			    asy->asy_ioaddr + DAT, *async->async_optr++);
2347 		}
2348 		async->async_flags |= ASYNC_PROGRESS;
2349 	}
2350 
2351 	if (fifo_len <= 0)
2352 		return;
2353 
2354 	ASYSETSOFT(asy);
2355 }
2356 
2357 /*
2358  * Interrupt on port: handle PPS event.  This function is only called
2359  * for a port on which PPS event handling has been enabled.
2360  */
2361 static void
2362 asy_ppsevent(struct asycom *asy, int msr)
2363 {
2364 	ASSERT(MUTEX_HELD(&asy->asy_excl_hi));
2365 
2366 	if (asy->asy_flags & ASY_PPS_EDGE) {
2367 		/* Have seen leading edge, now look for and record drop */
2368 		if ((msr & DCD) == 0)
2369 			asy->asy_flags &= ~ASY_PPS_EDGE;
2370 		/*
2371 		 * Waiting for leading edge, look for rise; stamp event and
2372 		 * calibrate kernel clock.
2373 		 */
2374 	} else if (msr & DCD) {
2375 			/*
2376 			 * This code captures a timestamp at the designated
2377 			 * transition of the PPS signal (DCD asserted).  The
2378 			 * code provides a pointer to the timestamp, as well
2379 			 * as the hardware counter value at the capture.
2380 			 *
2381 			 * Note: the kernel has nano based time values while
2382 			 * NTP requires micro based, an in-line fast algorithm
2383 			 * to convert nsec to usec is used here -- see hrt2ts()
2384 			 * in common/os/timers.c for a full description.
2385 			 */
2386 			struct timeval *tvp = &asy_ppsev.tv;
2387 			timestruc_t ts;
2388 			long nsec, usec;
2389 
2390 			asy->asy_flags |= ASY_PPS_EDGE;
2391 			LED_OFF;
2392 			gethrestime(&ts);
2393 			LED_ON;
2394 			nsec = ts.tv_nsec;
2395 			usec = nsec + (nsec >> 2);
2396 			usec = nsec + (usec >> 1);
2397 			usec = nsec + (usec >> 2);
2398 			usec = nsec + (usec >> 4);
2399 			usec = nsec - (usec >> 3);
2400 			usec = nsec + (usec >> 2);
2401 			usec = nsec + (usec >> 3);
2402 			usec = nsec + (usec >> 4);
2403 			usec = nsec + (usec >> 1);
2404 			usec = nsec + (usec >> 6);
2405 			tvp->tv_usec = usec >> 10;
2406 			tvp->tv_sec = ts.tv_sec;
2407 
2408 			++asy_ppsev.serial;
2409 
2410 			/*
2411 			 * Because the kernel keeps a high-resolution time,
2412 			 * pass the current highres timestamp in tvp and zero
2413 			 * in usec.
2414 			 */
2415 			ddi_hardpps(tvp, 0);
2416 	}
2417 }
2418 
2419 /*
2420  * Receiver interrupt: RxRDY interrupt, FIFO timeout interrupt or receive
2421  * error interrupt.
2422  * Try to put the character into the circular buffer for this line; if it
2423  * overflows, indicate a circular buffer overrun. If this port is always
2424  * to be serviced immediately, or the character is a STOP character, or
2425  * more than 15 characters have arrived, queue up a soft interrupt to
2426  * drain the circular buffer.
2427  * XXX - needs review for hw FIFOs support.
2428  */
2429 
2430 static void
2431 async_rxint(struct asycom *asy, uchar_t lsr)
2432 {
2433 	struct asyncline *async = asy->asy_priv;
2434 	uchar_t c;
2435 	uint_t s, needsoft = 0;
2436 	tty_common_t *tp;
2437 	int looplim = asy->asy_fifo_buf * 2;
2438 
2439 	ASSERT(MUTEX_HELD(&asy->asy_excl_hi));
2440 
2441 	tp = &async->async_ttycommon;
2442 	if (!(tp->t_cflag & CREAD)) {
2443 		while (lsr & (RCA|PARERR|FRMERR|BRKDET|OVRRUN)) {
2444 			(void) (ddi_get8(asy->asy_iohandle,
2445 			    asy->asy_ioaddr + DAT) & 0xff);
2446 			lsr = ddi_get8(asy->asy_iohandle,
2447 			    asy->asy_ioaddr + LSR);
2448 			if (looplim-- < 0)		/* limit loop */
2449 				break;
2450 		}
2451 		return; /* line is not open for read? */
2452 	}
2453 
2454 	while (lsr & (RCA|PARERR|FRMERR|BRKDET|OVRRUN)) {
2455 		c = 0;
2456 		s = 0;				/* reset error status */
2457 		if (lsr & RCA) {
2458 			c = ddi_get8(asy->asy_iohandle,
2459 			    asy->asy_ioaddr + DAT) & 0xff;
2460 
2461 			/*
2462 			 * We handle XON/XOFF char if IXON is set,
2463 			 * but if received char is _POSIX_VDISABLE,
2464 			 * we left it to the up level module.
2465 			 */
2466 			if (tp->t_iflag & IXON) {
2467 				if ((c == async->async_stopc) &&
2468 				    (c != _POSIX_VDISABLE)) {
2469 					async_flowcontrol_sw_output(asy,
2470 					    FLOW_STOP);
2471 					goto check_looplim;
2472 				} else if ((c == async->async_startc) &&
2473 				    (c != _POSIX_VDISABLE)) {
2474 					async_flowcontrol_sw_output(asy,
2475 					    FLOW_START);
2476 					needsoft = 1;
2477 					goto check_looplim;
2478 				}
2479 				if ((tp->t_iflag & IXANY) &&
2480 				    (async->async_flags & ASYNC_SW_OUT_FLW)) {
2481 					async_flowcontrol_sw_output(asy,
2482 					    FLOW_START);
2483 					needsoft = 1;
2484 				}
2485 			}
2486 		}
2487 
2488 		/*
2489 		 * Check for character break sequence
2490 		 */
2491 		if ((abort_enable == KIOCABORTALTERNATE) &&
2492 		    (asy->asy_flags & ASY_CONSOLE)) {
2493 			if (abort_charseq_recognize(c))
2494 				abort_sequence_enter((char *)NULL);
2495 		}
2496 
2497 		/* Handle framing errors */
2498 		if (lsr & (PARERR|FRMERR|BRKDET|OVRRUN)) {
2499 			if (lsr & PARERR) {
2500 				if (tp->t_iflag & INPCK) /* parity enabled */
2501 					s |= PERROR;
2502 			}
2503 
2504 			if (lsr & (FRMERR|BRKDET))
2505 				s |= FRERROR;
2506 			if (lsr & OVRRUN) {
2507 				async->async_hw_overrun = 1;
2508 				s |= OVERRUN;
2509 			}
2510 		}
2511 
2512 		if (s == 0)
2513 			if ((tp->t_iflag & PARMRK) &&
2514 			    !(tp->t_iflag & (IGNPAR|ISTRIP)) &&
2515 			    (c == 0377))
2516 				if (RING_POK(async, 2)) {
2517 					RING_PUT(async, 0377);
2518 					RING_PUT(async, c);
2519 				} else
2520 					async->async_sw_overrun = 1;
2521 			else
2522 				if (RING_POK(async, 1))
2523 					RING_PUT(async, c);
2524 				else
2525 					async->async_sw_overrun = 1;
2526 		else
2527 			if (s & FRERROR) /* Handle framing errors */
2528 				if (c == 0)
2529 					if ((asy->asy_flags & ASY_CONSOLE) &&
2530 					    (abort_enable !=
2531 					    KIOCABORTALTERNATE))
2532 						abort_sequence_enter((char *)0);
2533 					else
2534 						async->async_break++;
2535 				else
2536 					if (RING_POK(async, 1))
2537 						RING_MARK(async, c, s);
2538 					else
2539 						async->async_sw_overrun = 1;
2540 			else /* Parity errors are handled by ldterm */
2541 				if (RING_POK(async, 1))
2542 					RING_MARK(async, c, s);
2543 				else
2544 					async->async_sw_overrun = 1;
2545 check_looplim:
2546 		lsr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR);
2547 		if (looplim-- < 0)		/* limit loop */
2548 			break;
2549 	}
2550 	if ((RING_CNT(async) > (RINGSIZE * 3)/4) &&
2551 	    !(async->async_inflow_source & IN_FLOW_RINGBUFF)) {
2552 		async_flowcontrol_hw_input(asy, FLOW_STOP, IN_FLOW_RINGBUFF);
2553 		(void) async_flowcontrol_sw_input(asy, FLOW_STOP,
2554 		    IN_FLOW_RINGBUFF);
2555 	}
2556 
2557 	if ((async->async_flags & ASYNC_SERVICEIMM) || needsoft ||
2558 	    (RING_FRAC(async)) || (async->async_polltid == 0)) {
2559 		ASYSETSOFT(asy);	/* need a soft interrupt */
2560 	}
2561 }
2562 
2563 /*
2564  * Modem status interrupt.
2565  *
2566  * (Note: It is assumed that the MSR hasn't been read by asyintr().)
2567  */
2568 
2569 static void
2570 async_msint(struct asycom *asy)
2571 {
2572 	struct asyncline *async = asy->asy_priv;
2573 	int msr, t_cflag = async->async_ttycommon.t_cflag;
2574 #ifdef DEBUG
2575 	int instance = UNIT(async->async_dev);
2576 #endif
2577 
2578 	ASSERT(MUTEX_HELD(&asy->asy_excl_hi));
2579 
2580 async_msint_retry:
2581 	/* this resets the interrupt */
2582 	msr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MSR);
2583 	DEBUGCONT10(ASY_DEBUG_STATE,
2584 	    "async%d_msint call #%d:\n"
2585 	    "   transition: %3s %3s %3s %3s\n"
2586 	    "current state: %3s %3s %3s %3s\n",
2587 	    instance,
2588 	    ++(asy->asy_msint_cnt),
2589 	    (msr & DCTS) ? "DCTS" : "    ",
2590 	    (msr & DDSR) ? "DDSR" : "    ",
2591 	    (msr & DRI)  ? "DRI " : "    ",
2592 	    (msr & DDCD) ? "DDCD" : "    ",
2593 	    (msr & CTS)  ? "CTS " : "    ",
2594 	    (msr & DSR)  ? "DSR " : "    ",
2595 	    (msr & RI)   ? "RI  " : "    ",
2596 	    (msr & DCD)  ? "DCD " : "    ");
2597 
2598 	/* If CTS status is changed, do H/W output flow control */
2599 	if ((t_cflag & CRTSCTS) && (((asy->asy_msr ^ msr) & CTS) != 0))
2600 		async_flowcontrol_hw_output(asy,
2601 		    msr & CTS ? FLOW_START : FLOW_STOP);
2602 	/*
2603 	 * Reading MSR resets the interrupt, we save the
2604 	 * value of msr so that other functions could examine MSR by
2605 	 * looking at asy_msr.
2606 	 */
2607 	asy->asy_msr = (uchar_t)msr;
2608 
2609 	/* Handle PPS event */
2610 	if (asy->asy_flags & ASY_PPS)
2611 		asy_ppsevent(asy, msr);
2612 
2613 	async->async_ext++;
2614 	ASYSETSOFT(asy);
2615 	/*
2616 	 * We will make sure that the modem status presented to us
2617 	 * during the previous read has not changed. If the chip samples
2618 	 * the modem status on the falling edge of the interrupt line,
2619 	 * and uses this state as the base for detecting change of modem
2620 	 * status, we would miss a change of modem status event that occured
2621 	 * after we initiated a read MSR operation.
2622 	 */
2623 	msr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MSR);
2624 	if (STATES(msr) != STATES(asy->asy_msr))
2625 		goto	async_msint_retry;
2626 }
2627 
2628 /*
2629  * Handle a second-stage interrupt.
2630  */
2631 /*ARGSUSED*/
2632 uint_t
2633 asysoftintr(caddr_t intarg)
2634 {
2635 	struct asycom *asy = (struct asycom *)intarg;
2636 	struct asyncline *async;
2637 	int rv;
2638 	uint_t cc;
2639 
2640 	/*
2641 	 * Test and clear soft interrupt.
2642 	 */
2643 	mutex_enter(&asy->asy_soft_lock);
2644 	DEBUGCONT0(ASY_DEBUG_PROCS, "asysoftintr: enter\n");
2645 	rv = asy->asysoftpend;
2646 	if (rv != 0)
2647 		asy->asysoftpend = 0;
2648 	mutex_exit(&asy->asy_soft_lock);
2649 
2650 	if (rv) {
2651 		if (asy->asy_priv == NULL)
2652 			return (rv ? DDI_INTR_CLAIMED : DDI_INTR_UNCLAIMED);
2653 		async = (struct asyncline *)asy->asy_priv;
2654 		mutex_enter(&asy->asy_excl_hi);
2655 		if (asy->asy_flags & ASY_NEEDSOFT) {
2656 			asy->asy_flags &= ~ASY_NEEDSOFT;
2657 			mutex_exit(&asy->asy_excl_hi);
2658 			async_softint(asy);
2659 			mutex_enter(&asy->asy_excl_hi);
2660 		}
2661 
2662 		/*
2663 		 * There are some instances where the softintr is not
2664 		 * scheduled and hence not called. It so happens that
2665 		 * causes the last few characters to be stuck in the
2666 		 * ringbuffer. Hence, call the handler once again so
2667 		 * the last few characters are cleared.
2668 		 */
2669 		cc = RING_CNT(async);
2670 		mutex_exit(&asy->asy_excl_hi);
2671 		if (cc > 0)
2672 			(void) async_softint(asy);
2673 	}
2674 	return (rv ? DDI_INTR_CLAIMED : DDI_INTR_UNCLAIMED);
2675 }
2676 
2677 /*
2678  * Handle a software interrupt.
2679  */
2680 static void
2681 async_softint(struct asycom *asy)
2682 {
2683 	struct asyncline *async = asy->asy_priv;
2684 	uint_t	cc;
2685 	mblk_t	*bp;
2686 	queue_t	*q;
2687 	uchar_t	val;
2688 	uchar_t	c;
2689 	tty_common_t	*tp;
2690 	int nb;
2691 	int instance = UNIT(async->async_dev);
2692 
2693 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_softint\n", instance);
2694 	mutex_enter(&asy->asy_excl_hi);
2695 	if (asy->asy_flags & ASY_DOINGSOFT) {
2696 		asy->asy_flags |= ASY_DOINGSOFT_RETRY;
2697 		mutex_exit(&asy->asy_excl_hi);
2698 		return;
2699 	}
2700 	asy->asy_flags |= ASY_DOINGSOFT;
2701 begin:
2702 	asy->asy_flags &= ~ASY_DOINGSOFT_RETRY;
2703 	mutex_exit(&asy->asy_excl_hi);
2704 	mutex_enter(&asy->asy_excl);
2705 	tp = &async->async_ttycommon;
2706 	q = tp->t_readq;
2707 	if (async->async_flags & ASYNC_OUT_FLW_RESUME) {
2708 		if (async->async_ocnt > 0) {
2709 			mutex_enter(&asy->asy_excl_hi);
2710 			async_resume(async);
2711 			mutex_exit(&asy->asy_excl_hi);
2712 		} else {
2713 			if (async->async_xmitblk)
2714 				freeb(async->async_xmitblk);
2715 			async->async_xmitblk = NULL;
2716 			async_start(async);
2717 		}
2718 		async->async_flags &= ~ASYNC_OUT_FLW_RESUME;
2719 	}
2720 	mutex_enter(&asy->asy_excl_hi);
2721 	if (async->async_ext) {
2722 		async->async_ext = 0;
2723 		/* check for carrier up */
2724 		DEBUGCONT3(ASY_DEBUG_MODM2,
2725 		    "async%d_softint: asy_msr & DCD = %x, "
2726 		    "tp->t_flags & TS_SOFTCAR = %x\n",
2727 		    instance, asy->asy_msr & DCD, tp->t_flags & TS_SOFTCAR);
2728 
2729 		if (asy->asy_msr & DCD) {
2730 			/* carrier present */
2731 			if ((async->async_flags & ASYNC_CARR_ON) == 0) {
2732 				DEBUGCONT1(ASY_DEBUG_MODM2,
2733 				    "async%d_softint: set ASYNC_CARR_ON\n",
2734 				    instance);
2735 				async->async_flags |= ASYNC_CARR_ON;
2736 				if (async->async_flags & ASYNC_ISOPEN) {
2737 					mutex_exit(&asy->asy_excl_hi);
2738 					mutex_exit(&asy->asy_excl);
2739 					(void) putctl(q, M_UNHANGUP);
2740 					mutex_enter(&asy->asy_excl);
2741 					mutex_enter(&asy->asy_excl_hi);
2742 				}
2743 				cv_broadcast(&async->async_flags_cv);
2744 			}
2745 		} else {
2746 			if ((async->async_flags & ASYNC_CARR_ON) &&
2747 			    !(tp->t_cflag & CLOCAL) &&
2748 			    !(tp->t_flags & TS_SOFTCAR)) {
2749 				int flushflag;
2750 
2751 				DEBUGCONT1(ASY_DEBUG_MODEM,
2752 				    "async%d_softint: carrier dropped, "
2753 				    "so drop DTR\n",
2754 				    instance);
2755 				/*
2756 				 * Carrier went away.
2757 				 * Drop DTR, abort any output in
2758 				 * progress, indicate that output is
2759 				 * not stopped, and send a hangup
2760 				 * notification upstream.
2761 				 */
2762 				val = ddi_get8(asy->asy_iohandle,
2763 				    asy->asy_ioaddr + MCR);
2764 				ddi_put8(asy->asy_iohandle,
2765 				    asy->asy_ioaddr + MCR, (val & ~DTR));
2766 
2767 				if (async->async_flags & ASYNC_BUSY) {
2768 					DEBUGCONT0(ASY_DEBUG_BUSY,
2769 					    "async_softint: "
2770 					    "Carrier dropped.  "
2771 					    "Clearing async_ocnt\n");
2772 					async->async_ocnt = 0;
2773 				}	/* if */
2774 
2775 				async->async_flags &= ~ASYNC_STOPPED;
2776 				if (async->async_flags & ASYNC_ISOPEN) {
2777 					mutex_exit(&asy->asy_excl_hi);
2778 					mutex_exit(&asy->asy_excl);
2779 					(void) putctl(q, M_HANGUP);
2780 					mutex_enter(&asy->asy_excl);
2781 					DEBUGCONT1(ASY_DEBUG_MODEM,
2782 					    "async%d_softint: "
2783 					    "putctl(q, M_HANGUP)\n",
2784 					    instance);
2785 					/*
2786 					 * Flush FIFO buffers
2787 					 * Any data left in there is invalid now
2788 					 */
2789 					if (asy->asy_use_fifo == FIFO_ON)
2790 						asy_reset_fifo(asy, FIFOTXFLSH);
2791 					/*
2792 					 * Flush our write queue if we have one.
2793 					 * If we're in the midst of close, then
2794 					 * flush everything. Don't leave stale
2795 					 * ioctls lying about.
2796 					 */
2797 					flushflag = (async->async_flags &
2798 					    ASYNC_CLOSING) ? FLUSHALL :
2799 					    FLUSHDATA;
2800 					flushq(tp->t_writeq, flushflag);
2801 
2802 					/* active msg */
2803 					bp = async->async_xmitblk;
2804 					if (bp != NULL) {
2805 						freeb(bp);
2806 						async->async_xmitblk = NULL;
2807 					}
2808 
2809 					mutex_enter(&asy->asy_excl_hi);
2810 					async->async_flags &= ~ASYNC_BUSY;
2811 					/*
2812 					 * This message warns of Carrier loss
2813 					 * with data left to transmit can hang
2814 					 * the system.
2815 					 */
2816 					DEBUGCONT0(ASY_DEBUG_MODEM,
2817 					    "async_softint: Flushing to "
2818 					    "prevent HUPCL hanging\n");
2819 				}	/* if (ASYNC_ISOPEN) */
2820 			}	/* if (ASYNC_CARR_ON && CLOCAL) */
2821 			async->async_flags &= ~ASYNC_CARR_ON;
2822 			cv_broadcast(&async->async_flags_cv);
2823 		}	/* else */
2824 	}	/* if (async->async_ext) */
2825 
2826 	mutex_exit(&asy->asy_excl_hi);
2827 
2828 	/*
2829 	 * If data has been added to the circular buffer, remove
2830 	 * it from the buffer, and send it up the stream if there's
2831 	 * somebody listening. Try to do it 16 bytes at a time. If we
2832 	 * have more than 16 bytes to move, move 16 byte chunks and
2833 	 * leave the rest for next time around (maybe it will grow).
2834 	 */
2835 	mutex_enter(&asy->asy_excl_hi);
2836 	if (!(async->async_flags & ASYNC_ISOPEN)) {
2837 		RING_INIT(async);
2838 		goto rv;
2839 	}
2840 	if ((cc = RING_CNT(async)) == 0)
2841 		goto rv;
2842 	mutex_exit(&asy->asy_excl_hi);
2843 
2844 	if (!canput(q)) {
2845 		mutex_enter(&asy->asy_excl_hi);
2846 		if (!(async->async_inflow_source & IN_FLOW_STREAMS)) {
2847 			async_flowcontrol_hw_input(asy, FLOW_STOP,
2848 			    IN_FLOW_STREAMS);
2849 			(void) async_flowcontrol_sw_input(asy, FLOW_STOP,
2850 			    IN_FLOW_STREAMS);
2851 		}
2852 		goto rv;
2853 	}
2854 	if (async->async_inflow_source & IN_FLOW_STREAMS) {
2855 		mutex_enter(&asy->asy_excl_hi);
2856 		async_flowcontrol_hw_input(asy, FLOW_START,
2857 		    IN_FLOW_STREAMS);
2858 		(void) async_flowcontrol_sw_input(asy, FLOW_START,
2859 		    IN_FLOW_STREAMS);
2860 		mutex_exit(&asy->asy_excl_hi);
2861 	}
2862 
2863 	DEBUGCONT2(ASY_DEBUG_INPUT, "async%d_softint: %d char(s) in queue.\n",
2864 	    instance, cc);
2865 
2866 	if (!(bp = allocb(cc, BPRI_MED))) {
2867 		mutex_exit(&asy->asy_excl);
2868 		ttycommon_qfull(&async->async_ttycommon, q);
2869 		mutex_enter(&asy->asy_excl);
2870 		mutex_enter(&asy->asy_excl_hi);
2871 		goto rv;
2872 	}
2873 	mutex_enter(&asy->asy_excl_hi);
2874 	do {
2875 		if (RING_ERR(async, S_ERRORS)) {
2876 			RING_UNMARK(async);
2877 			c = RING_GET(async);
2878 			break;
2879 		} else
2880 			*bp->b_wptr++ = RING_GET(async);
2881 	} while (--cc);
2882 	mutex_exit(&asy->asy_excl_hi);
2883 	mutex_exit(&asy->asy_excl);
2884 	if (bp->b_wptr > bp->b_rptr) {
2885 			if (!canput(q)) {
2886 				asyerror(CE_NOTE, "asy%d: local queue full",
2887 				    instance);
2888 				freemsg(bp);
2889 			} else
2890 				(void) putq(q, bp);
2891 	} else
2892 		freemsg(bp);
2893 	/*
2894 	 * If we have a parity error, then send
2895 	 * up an M_BREAK with the "bad"
2896 	 * character as an argument. Let ldterm
2897 	 * figure out what to do with the error.
2898 	 */
2899 	if (cc)
2900 		(void) putctl1(q, M_BREAK, c);
2901 	mutex_enter(&asy->asy_excl);
2902 	mutex_enter(&asy->asy_excl_hi);
2903 	if (cc) {
2904 		ASYSETSOFT(asy);	/* finish cc chars */
2905 	}
2906 rv:
2907 	if ((RING_CNT(async) < (RINGSIZE/4)) &&
2908 	    (async->async_inflow_source & IN_FLOW_RINGBUFF)) {
2909 		async_flowcontrol_hw_input(asy, FLOW_START, IN_FLOW_RINGBUFF);
2910 		(void) async_flowcontrol_sw_input(asy, FLOW_START,
2911 		    IN_FLOW_RINGBUFF);
2912 	}
2913 
2914 	/*
2915 	 * If a transmission has finished, indicate that it's finished,
2916 	 * and start that line up again.
2917 	 */
2918 	if (async->async_break > 0) {
2919 		nb = async->async_break;
2920 		async->async_break = 0;
2921 		if (async->async_flags & ASYNC_ISOPEN) {
2922 			mutex_exit(&asy->asy_excl_hi);
2923 			mutex_exit(&asy->asy_excl);
2924 			for (; nb > 0; nb--)
2925 				(void) putctl(q, M_BREAK);
2926 			mutex_enter(&asy->asy_excl);
2927 			mutex_enter(&asy->asy_excl_hi);
2928 		}
2929 	}
2930 	if (async->async_ocnt <= 0 && (async->async_flags & ASYNC_BUSY)) {
2931 		DEBUGCONT2(ASY_DEBUG_BUSY,
2932 		    "async%d_softint: Clearing ASYNC_BUSY.  async_ocnt=%d\n",
2933 		    instance,
2934 		    async->async_ocnt);
2935 		async->async_flags &= ~ASYNC_BUSY;
2936 		mutex_exit(&asy->asy_excl_hi);
2937 		if (async->async_xmitblk)
2938 			freeb(async->async_xmitblk);
2939 		async->async_xmitblk = NULL;
2940 		async_start(async);
2941 		/*
2942 		 * If the flag isn't set after doing the async_start above, we
2943 		 * may have finished all the queued output.  Signal any thread
2944 		 * stuck in close.
2945 		 */
2946 		if (!(async->async_flags & ASYNC_BUSY))
2947 			cv_broadcast(&async->async_flags_cv);
2948 		mutex_enter(&asy->asy_excl_hi);
2949 	}
2950 	/*
2951 	 * A note about these overrun bits: all they do is *tell* someone
2952 	 * about an error- They do not track multiple errors. In fact,
2953 	 * you could consider them latched register bits if you like.
2954 	 * We are only interested in printing the error message once for
2955 	 * any cluster of overrun errrors.
2956 	 */
2957 	if (async->async_hw_overrun) {
2958 		if (async->async_flags & ASYNC_ISOPEN) {
2959 			mutex_exit(&asy->asy_excl_hi);
2960 			mutex_exit(&asy->asy_excl);
2961 			asyerror(CE_NOTE, "asy%d: silo overflow", instance);
2962 			mutex_enter(&asy->asy_excl);
2963 			mutex_enter(&asy->asy_excl_hi);
2964 		}
2965 		async->async_hw_overrun = 0;
2966 	}
2967 	if (async->async_sw_overrun) {
2968 		if (async->async_flags & ASYNC_ISOPEN) {
2969 			mutex_exit(&asy->asy_excl_hi);
2970 			mutex_exit(&asy->asy_excl);
2971 			asyerror(CE_NOTE, "asy%d: ring buffer overflow",
2972 			    instance);
2973 			mutex_enter(&asy->asy_excl);
2974 			mutex_enter(&asy->asy_excl_hi);
2975 		}
2976 		async->async_sw_overrun = 0;
2977 	}
2978 	if (asy->asy_flags & ASY_DOINGSOFT_RETRY) {
2979 		mutex_exit(&asy->asy_excl);
2980 		goto begin;
2981 	}
2982 	asy->asy_flags &= ~ASY_DOINGSOFT;
2983 	mutex_exit(&asy->asy_excl_hi);
2984 	mutex_exit(&asy->asy_excl);
2985 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_softint: done\n", instance);
2986 }
2987 
2988 /*
2989  * Restart output on a line after a delay or break timer expired.
2990  */
2991 static void
2992 async_restart(void *arg)
2993 {
2994 	struct asyncline *async = (struct asyncline *)arg;
2995 	struct asycom *asy = async->async_common;
2996 	uchar_t lcr;
2997 
2998 	/*
2999 	 * If break timer expired, turn off the break bit.
3000 	 */
3001 #ifdef DEBUG
3002 	int instance = UNIT(async->async_dev);
3003 
3004 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_restart\n", instance);
3005 #endif
3006 	mutex_enter(&asy->asy_excl);
3007 	/*
3008 	 * If ASYNC_OUT_SUSPEND is also set, we don't really
3009 	 * clean the HW break, TIOCCBRK is responsible for this.
3010 	 */
3011 	if ((async->async_flags & ASYNC_BREAK) &&
3012 	    !(async->async_flags & ASYNC_OUT_SUSPEND)) {
3013 		mutex_enter(&asy->asy_excl_hi);
3014 		lcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
3015 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
3016 		    (lcr & ~SETBREAK));
3017 		mutex_exit(&asy->asy_excl_hi);
3018 	}
3019 	async->async_flags &= ~(ASYNC_DELAY|ASYNC_BREAK);
3020 	cv_broadcast(&async->async_flags_cv);
3021 	async_start(async);
3022 
3023 	mutex_exit(&asy->asy_excl);
3024 }
3025 
3026 static void
3027 async_start(struct asyncline *async)
3028 {
3029 	async_nstart(async, 0);
3030 }
3031 
3032 /*
3033  * Start output on a line, unless it's busy, frozen, or otherwise.
3034  */
3035 /*ARGSUSED*/
3036 static void
3037 async_nstart(struct asyncline *async, int mode)
3038 {
3039 	struct asycom *asy = async->async_common;
3040 	int cc;
3041 	queue_t *q;
3042 	mblk_t *bp;
3043 	uchar_t *xmit_addr;
3044 	uchar_t	val;
3045 	int	fifo_len = 1;
3046 	boolean_t didsome;
3047 	mblk_t *nbp;
3048 
3049 #ifdef DEBUG
3050 	int instance = UNIT(async->async_dev);
3051 
3052 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_nstart\n", instance);
3053 #endif
3054 	if (asy->asy_use_fifo == FIFO_ON) {
3055 		fifo_len = asy->asy_fifo_buf; /* with FIFO buffers */
3056 		if (fifo_len > asy_max_tx_fifo)
3057 			fifo_len = asy_max_tx_fifo;
3058 	}
3059 
3060 	ASSERT(mutex_owned(&asy->asy_excl));
3061 
3062 	/*
3063 	 * If the chip is busy (i.e., we're waiting for a break timeout
3064 	 * to expire, or for the current transmission to finish, or for
3065 	 * output to finish draining from chip), don't grab anything new.
3066 	 */
3067 	if (async->async_flags & (ASYNC_BREAK|ASYNC_BUSY)) {
3068 		DEBUGCONT2((mode? ASY_DEBUG_OUT : 0),
3069 		    "async%d_nstart: start %s.\n",
3070 		    instance,
3071 		    async->async_flags & ASYNC_BREAK ? "break" : "busy");
3072 		return;
3073 	}
3074 
3075 	/*
3076 	 * Check only pended sw input flow control.
3077 	 */
3078 	mutex_enter(&asy->asy_excl_hi);
3079 	if (async_flowcontrol_sw_input(asy, FLOW_CHECK, IN_FLOW_NULL))
3080 		fifo_len--;
3081 	mutex_exit(&asy->asy_excl_hi);
3082 
3083 	/*
3084 	 * If we're waiting for a delay timeout to expire, don't grab
3085 	 * anything new.
3086 	 */
3087 	if (async->async_flags & ASYNC_DELAY) {
3088 		DEBUGCONT1((mode? ASY_DEBUG_OUT : 0),
3089 		    "async%d_nstart: start ASYNC_DELAY.\n", instance);
3090 		return;
3091 	}
3092 
3093 	if ((q = async->async_ttycommon.t_writeq) == NULL) {
3094 		DEBUGCONT1((mode? ASY_DEBUG_OUT : 0),
3095 		    "async%d_nstart: start writeq is null.\n", instance);
3096 		return;	/* not attached to a stream */
3097 	}
3098 
3099 	for (;;) {
3100 		if ((bp = getq(q)) == NULL)
3101 			return;	/* no data to transmit */
3102 
3103 		/*
3104 		 * We have a message block to work on.
3105 		 * Check whether it's a break, a delay, or an ioctl (the latter
3106 		 * occurs if the ioctl in question was waiting for the output
3107 		 * to drain).  If it's one of those, process it immediately.
3108 		 */
3109 		switch (bp->b_datap->db_type) {
3110 
3111 		case M_BREAK:
3112 			/*
3113 			 * Set the break bit, and arrange for "async_restart"
3114 			 * to be called in 1/4 second; it will turn the
3115 			 * break bit off, and call "async_start" to grab
3116 			 * the next message.
3117 			 */
3118 			mutex_enter(&asy->asy_excl_hi);
3119 			val = ddi_get8(asy->asy_iohandle,
3120 			    asy->asy_ioaddr + LCR);
3121 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
3122 			    (val | SETBREAK));
3123 			mutex_exit(&asy->asy_excl_hi);
3124 			async->async_flags |= ASYNC_BREAK;
3125 			(void) timeout(async_restart, (caddr_t)async,
3126 			    drv_usectohz(1000000)/4);
3127 			freemsg(bp);
3128 			return;	/* wait for this to finish */
3129 
3130 		case M_DELAY:
3131 			/*
3132 			 * Arrange for "async_restart" to be called when the
3133 			 * delay expires; it will turn ASYNC_DELAY off,
3134 			 * and call "async_start" to grab the next message.
3135 			 */
3136 			(void) timeout(async_restart, (caddr_t)async,
3137 			    (int)(*(unsigned char *)bp->b_rptr + 6));
3138 			async->async_flags |= ASYNC_DELAY;
3139 			freemsg(bp);
3140 			return;	/* wait for this to finish */
3141 
3142 		case M_IOCTL:
3143 			/*
3144 			 * This ioctl was waiting for the output ahead of
3145 			 * it to drain; obviously, it has.  Do it, and
3146 			 * then grab the next message after it.
3147 			 */
3148 			mutex_exit(&asy->asy_excl);
3149 			async_ioctl(async, q, bp);
3150 			mutex_enter(&asy->asy_excl);
3151 			continue;
3152 		}
3153 
3154 		while (bp != NULL && ((cc = MBLKL(bp)) == 0)) {
3155 			nbp = bp->b_cont;
3156 			freeb(bp);
3157 			bp = nbp;
3158 		}
3159 		if (bp != NULL)
3160 			break;
3161 	}
3162 
3163 	/*
3164 	 * We have data to transmit.  If output is stopped, put
3165 	 * it back and try again later.
3166 	 */
3167 	if (async->async_flags & (ASYNC_HW_OUT_FLW | ASYNC_SW_OUT_FLW |
3168 	    ASYNC_STOPPED | ASYNC_OUT_SUSPEND)) {
3169 		(void) putbq(q, bp);
3170 		return;
3171 	}
3172 
3173 	async->async_xmitblk = bp;
3174 	xmit_addr = bp->b_rptr;
3175 	bp = bp->b_cont;
3176 	if (bp != NULL)
3177 		(void) putbq(q, bp);	/* not done with this message yet */
3178 
3179 	/*
3180 	 * In 5-bit mode, the high order bits are used
3181 	 * to indicate character sizes less than five,
3182 	 * so we need to explicitly mask before transmitting
3183 	 */
3184 	if ((async->async_ttycommon.t_cflag & CSIZE) == CS5) {
3185 		unsigned char *p = xmit_addr;
3186 		int cnt = cc;
3187 
3188 		while (cnt--)
3189 			*p++ &= (unsigned char) 0x1f;
3190 	}
3191 
3192 	/*
3193 	 * Set up this block for pseudo-DMA.
3194 	 */
3195 	mutex_enter(&asy->asy_excl_hi);
3196 	/*
3197 	 * If the transmitter is ready, shove the first
3198 	 * character out.
3199 	 */
3200 	didsome = B_FALSE;
3201 	while (--fifo_len >= 0 && cc > 0) {
3202 		if (!(ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR) &
3203 		    XHRE))
3204 			break;
3205 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
3206 		    *xmit_addr++);
3207 		cc--;
3208 		didsome = B_TRUE;
3209 	}
3210 	async->async_optr = xmit_addr;
3211 	async->async_ocnt = cc;
3212 	if (didsome)
3213 		async->async_flags |= ASYNC_PROGRESS;
3214 	DEBUGCONT2(ASY_DEBUG_BUSY,
3215 	    "async%d_nstart: Set ASYNC_BUSY.  async_ocnt=%d\n",
3216 	    instance, async->async_ocnt);
3217 	async->async_flags |= ASYNC_BUSY;
3218 	mutex_exit(&asy->asy_excl_hi);
3219 }
3220 
3221 /*
3222  * Resume output by poking the transmitter.
3223  */
3224 static void
3225 async_resume(struct asyncline *async)
3226 {
3227 	struct asycom *asy = async->async_common;
3228 #ifdef DEBUG
3229 	int instance;
3230 #endif
3231 
3232 	ASSERT(mutex_owned(&asy->asy_excl_hi));
3233 #ifdef DEBUG
3234 	instance = UNIT(async->async_dev);
3235 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_resume\n", instance);
3236 #endif
3237 
3238 	if (ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR) & XHRE) {
3239 		if (async_flowcontrol_sw_input(asy, FLOW_CHECK, IN_FLOW_NULL))
3240 			return;
3241 		if (async->async_ocnt > 0 &&
3242 		    !(async->async_flags &
3243 		    (ASYNC_HW_OUT_FLW|ASYNC_SW_OUT_FLW|ASYNC_OUT_SUSPEND))) {
3244 			ddi_put8(asy->asy_iohandle,
3245 			    asy->asy_ioaddr + DAT, *async->async_optr++);
3246 			async->async_ocnt--;
3247 			async->async_flags |= ASYNC_PROGRESS;
3248 		}
3249 	}
3250 }
3251 
3252 /*
3253  * Hold the untimed break to last the minimum time.
3254  */
3255 static void
3256 async_hold_utbrk(void *arg)
3257 {
3258 	struct asyncline *async = arg;
3259 	struct asycom *asy = async->async_common;
3260 
3261 	mutex_enter(&asy->asy_excl);
3262 	async->async_flags &= ~ASYNC_HOLD_UTBRK;
3263 	cv_broadcast(&async->async_flags_cv);
3264 	async->async_utbrktid = 0;
3265 	mutex_exit(&asy->asy_excl);
3266 }
3267 
3268 /*
3269  * Resume the untimed break.
3270  */
3271 static void
3272 async_resume_utbrk(struct asyncline *async)
3273 {
3274 	uchar_t	val;
3275 	struct asycom *asy = async->async_common;
3276 	ASSERT(mutex_owned(&asy->asy_excl));
3277 
3278 	/*
3279 	 * Because the wait time is very short,
3280 	 * so we use uninterruptably wait.
3281 	 */
3282 	while (async->async_flags & ASYNC_HOLD_UTBRK) {
3283 		cv_wait(&async->async_flags_cv, &asy->asy_excl);
3284 	}
3285 	mutex_enter(&asy->asy_excl_hi);
3286 	/*
3287 	 * Timed break and untimed break can exist simultaneously,
3288 	 * if ASYNC_BREAK is also set at here, we don't
3289 	 * really clean the HW break.
3290 	 */
3291 	if (!(async->async_flags & ASYNC_BREAK)) {
3292 		val = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
3293 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
3294 		    (val & ~SETBREAK));
3295 	}
3296 	async->async_flags &= ~ASYNC_OUT_SUSPEND;
3297 	cv_broadcast(&async->async_flags_cv);
3298 	if (async->async_ocnt > 0) {
3299 		async_resume(async);
3300 		mutex_exit(&asy->asy_excl_hi);
3301 	} else {
3302 		async->async_flags &= ~ASYNC_BUSY;
3303 		mutex_exit(&asy->asy_excl_hi);
3304 		if (async->async_xmitblk != NULL) {
3305 			freeb(async->async_xmitblk);
3306 			async->async_xmitblk = NULL;
3307 		}
3308 		async_start(async);
3309 	}
3310 }
3311 
3312 /*
3313  * Process an "ioctl" message sent down to us.
3314  * Note that we don't need to get any locks until we are ready to access
3315  * the hardware.  Nothing we access until then is going to be altered
3316  * outside of the STREAMS framework, so we should be safe.
3317  */
3318 int asydelay = 10000;
3319 static void
3320 async_ioctl(struct asyncline *async, queue_t *wq, mblk_t *mp)
3321 {
3322 	struct asycom *asy = async->async_common;
3323 	tty_common_t  *tp = &async->async_ttycommon;
3324 	struct iocblk *iocp;
3325 	unsigned datasize;
3326 	int error = 0;
3327 	uchar_t val;
3328 	mblk_t *datamp;
3329 	unsigned int index;
3330 
3331 #ifdef DEBUG
3332 	int instance = UNIT(async->async_dev);
3333 
3334 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_ioctl\n", instance);
3335 #endif
3336 
3337 	if (tp->t_iocpending != NULL) {
3338 		/*
3339 		 * We were holding an "ioctl" response pending the
3340 		 * availability of an "mblk" to hold data to be passed up;
3341 		 * another "ioctl" came through, which means that "ioctl"
3342 		 * must have timed out or been aborted.
3343 		 */
3344 		freemsg(async->async_ttycommon.t_iocpending);
3345 		async->async_ttycommon.t_iocpending = NULL;
3346 	}
3347 
3348 	iocp = (struct iocblk *)mp->b_rptr;
3349 
3350 	/*
3351 	 * For TIOCMGET and the PPS ioctls, do NOT call ttycommon_ioctl()
3352 	 * because this function frees up the message block (mp->b_cont) that
3353 	 * contains the user location where we pass back the results.
3354 	 *
3355 	 * Similarly, CONSOPENPOLLEDIO needs ioc_count, which ttycommon_ioctl
3356 	 * zaps.  We know that ttycommon_ioctl doesn't know any CONS*
3357 	 * ioctls, so keep the others safe too.
3358 	 */
3359 	DEBUGCONT2(ASY_DEBUG_IOCTL, "async%d_ioctl: %s\n",
3360 	    instance,
3361 	    iocp->ioc_cmd == TIOCMGET ? "TIOCMGET" :
3362 	    iocp->ioc_cmd == TIOCMSET ? "TIOCMSET" :
3363 	    iocp->ioc_cmd == TIOCMBIS ? "TIOCMBIS" :
3364 	    iocp->ioc_cmd == TIOCMBIC ? "TIOCMBIC" :
3365 	    "other");
3366 
3367 	switch (iocp->ioc_cmd) {
3368 	case TIOCMGET:
3369 	case TIOCGPPS:
3370 	case TIOCSPPS:
3371 	case TIOCGPPSEV:
3372 	case CONSOPENPOLLEDIO:
3373 	case CONSCLOSEPOLLEDIO:
3374 	case CONSSETABORTENABLE:
3375 	case CONSGETABORTENABLE:
3376 		error = -1; /* Do Nothing */
3377 		break;
3378 	default:
3379 
3380 		/*
3381 		 * The only way in which "ttycommon_ioctl" can fail is if the
3382 		 * "ioctl" requires a response containing data to be returned
3383 		 * to the user, and no mblk could be allocated for the data.
3384 		 * No such "ioctl" alters our state.  Thus, we always go ahead
3385 		 * and do any state-changes the "ioctl" calls for.  If we
3386 		 * couldn't allocate the data, "ttycommon_ioctl" has stashed
3387 		 * the "ioctl" away safely, so we just call "bufcall" to
3388 		 * request that we be called back when we stand a better
3389 		 * chance of allocating the data.
3390 		 */
3391 		if ((datasize = ttycommon_ioctl(tp, wq, mp, &error)) != 0) {
3392 			if (async->async_wbufcid)
3393 				unbufcall(async->async_wbufcid);
3394 			async->async_wbufcid = bufcall(datasize, BPRI_HI,
3395 			    (void (*)(void *)) async_reioctl,
3396 			    (void *)(intptr_t)async->async_common->asy_unit);
3397 			return;
3398 		}
3399 	}
3400 
3401 	mutex_enter(&asy->asy_excl);
3402 
3403 	if (error == 0) {
3404 		/*
3405 		 * "ttycommon_ioctl" did most of the work; we just use the
3406 		 * data it set up.
3407 		 */
3408 		switch (iocp->ioc_cmd) {
3409 
3410 		case TCSETS:
3411 			mutex_enter(&asy->asy_excl_hi);
3412 			if (asy_baudok(asy))
3413 				asy_program(asy, ASY_NOINIT);
3414 			else
3415 				error = EINVAL;
3416 			mutex_exit(&asy->asy_excl_hi);
3417 			break;
3418 		case TCSETSF:
3419 		case TCSETSW:
3420 		case TCSETA:
3421 		case TCSETAW:
3422 		case TCSETAF:
3423 			mutex_enter(&asy->asy_excl_hi);
3424 			if (!asy_baudok(asy))
3425 				error = EINVAL;
3426 			else {
3427 				if (asy_isbusy(asy))
3428 					asy_waiteot(asy);
3429 				asy_program(asy, ASY_NOINIT);
3430 			}
3431 			mutex_exit(&asy->asy_excl_hi);
3432 			break;
3433 		}
3434 	} else if (error < 0) {
3435 		/*
3436 		 * "ttycommon_ioctl" didn't do anything; we process it here.
3437 		 */
3438 		error = 0;
3439 		switch (iocp->ioc_cmd) {
3440 
3441 		case TIOCGPPS:
3442 			/*
3443 			 * Get PPS on/off.
3444 			 */
3445 			if (mp->b_cont != NULL)
3446 				freemsg(mp->b_cont);
3447 
3448 			mp->b_cont = allocb(sizeof (int), BPRI_HI);
3449 			if (mp->b_cont == NULL) {
3450 				error = ENOMEM;
3451 				break;
3452 			}
3453 			if (asy->asy_flags & ASY_PPS)
3454 				*(int *)mp->b_cont->b_wptr = 1;
3455 			else
3456 				*(int *)mp->b_cont->b_wptr = 0;
3457 			mp->b_cont->b_wptr += sizeof (int);
3458 			mp->b_datap->db_type = M_IOCACK;
3459 			iocp->ioc_count = sizeof (int);
3460 			break;
3461 
3462 		case TIOCSPPS:
3463 			/*
3464 			 * Set PPS on/off.
3465 			 */
3466 			error = miocpullup(mp, sizeof (int));
3467 			if (error != 0)
3468 				break;
3469 
3470 			mutex_enter(&asy->asy_excl_hi);
3471 			if (*(int *)mp->b_cont->b_rptr)
3472 				asy->asy_flags |= ASY_PPS;
3473 			else
3474 				asy->asy_flags &= ~ASY_PPS;
3475 			/* Reset edge sense */
3476 			asy->asy_flags &= ~ASY_PPS_EDGE;
3477 			mutex_exit(&asy->asy_excl_hi);
3478 			mp->b_datap->db_type = M_IOCACK;
3479 			break;
3480 
3481 		case TIOCGPPSEV:
3482 		{
3483 			/*
3484 			 * Get PPS event data.
3485 			 */
3486 			mblk_t *bp;
3487 			void *buf;
3488 #ifdef _SYSCALL32_IMPL
3489 			struct ppsclockev32 p32;
3490 #endif
3491 			struct ppsclockev ppsclockev;
3492 
3493 			if (mp->b_cont != NULL) {
3494 				freemsg(mp->b_cont);
3495 				mp->b_cont = NULL;
3496 			}
3497 
3498 			if ((asy->asy_flags & ASY_PPS) == 0) {
3499 				error = ENXIO;
3500 				break;
3501 			}
3502 
3503 			/* Protect from incomplete asy_ppsev */
3504 			mutex_enter(&asy->asy_excl_hi);
3505 			ppsclockev = asy_ppsev;
3506 			mutex_exit(&asy->asy_excl_hi);
3507 
3508 #ifdef _SYSCALL32_IMPL
3509 			if ((iocp->ioc_flag & IOC_MODELS) != IOC_NATIVE) {
3510 				TIMEVAL_TO_TIMEVAL32(&p32.tv, &ppsclockev.tv);
3511 				p32.serial = ppsclockev.serial;
3512 				buf = &p32;
3513 				iocp->ioc_count = sizeof (struct ppsclockev32);
3514 			} else
3515 #endif
3516 			{
3517 				buf = &ppsclockev;
3518 				iocp->ioc_count = sizeof (struct ppsclockev);
3519 			}
3520 
3521 			if ((bp = allocb(iocp->ioc_count, BPRI_HI)) == NULL) {
3522 				error = ENOMEM;
3523 				break;
3524 			}
3525 			mp->b_cont = bp;
3526 
3527 			bcopy(buf, bp->b_wptr, iocp->ioc_count);
3528 			bp->b_wptr += iocp->ioc_count;
3529 			mp->b_datap->db_type = M_IOCACK;
3530 			break;
3531 		}
3532 
3533 		case TCSBRK:
3534 			error = miocpullup(mp, sizeof (int));
3535 			if (error != 0)
3536 				break;
3537 
3538 			if (*(int *)mp->b_cont->b_rptr == 0) {
3539 
3540 				/*
3541 				 * XXX Arrangements to ensure that a break
3542 				 * isn't in progress should be sufficient.
3543 				 * This ugly delay() is the only thing
3544 				 * that seems to work on the NCR Worldmark.
3545 				 * It should be replaced. Note that an
3546 				 * asy_waiteot() also does not work.
3547 				 */
3548 				if (asydelay)
3549 					delay(drv_usectohz(asydelay));
3550 
3551 				while (async->async_flags & ASYNC_BREAK) {
3552 					cv_wait(&async->async_flags_cv,
3553 					    &asy->asy_excl);
3554 				}
3555 				mutex_enter(&asy->asy_excl_hi);
3556 				/*
3557 				 * We loop until the TSR is empty and then
3558 				 * set the break.  ASYNC_BREAK has been set
3559 				 * to ensure that no characters are
3560 				 * transmitted while the TSR is being
3561 				 * flushed and SOUT is being used for the
3562 				 * break signal.
3563 				 *
3564 				 * The wait period is equal to
3565 				 * clock / (baud * 16) * 16 * 2.
3566 				 */
3567 				index = BAUDINDEX(
3568 				    async->async_ttycommon.t_cflag);
3569 				async->async_flags |= ASYNC_BREAK;
3570 
3571 				while ((ddi_get8(asy->asy_iohandle,
3572 				    asy->asy_ioaddr + LSR) & XSRE) == 0) {
3573 					mutex_exit(&asy->asy_excl_hi);
3574 					mutex_exit(&asy->asy_excl);
3575 					drv_usecwait(
3576 					    32*asyspdtab[index] & 0xfff);
3577 					mutex_enter(&asy->asy_excl);
3578 					mutex_enter(&asy->asy_excl_hi);
3579 				}
3580 				/*
3581 				 * Arrange for "async_restart"
3582 				 * to be called in 1/4 second;
3583 				 * it will turn the break bit off, and call
3584 				 * "async_start" to grab the next message.
3585 				 */
3586 				val = ddi_get8(asy->asy_iohandle,
3587 				    asy->asy_ioaddr + LCR);
3588 				ddi_put8(asy->asy_iohandle,
3589 				    asy->asy_ioaddr + LCR,
3590 				    (val | SETBREAK));
3591 				mutex_exit(&asy->asy_excl_hi);
3592 				(void) timeout(async_restart, (caddr_t)async,
3593 				    drv_usectohz(1000000)/4);
3594 			} else {
3595 				DEBUGCONT1(ASY_DEBUG_OUT,
3596 				    "async%d_ioctl: wait for flush.\n",
3597 				    instance);
3598 				mutex_enter(&asy->asy_excl_hi);
3599 				asy_waiteot(asy);
3600 				mutex_exit(&asy->asy_excl_hi);
3601 				DEBUGCONT1(ASY_DEBUG_OUT,
3602 				    "async%d_ioctl: ldterm satisfied.\n",
3603 				    instance);
3604 			}
3605 			break;
3606 
3607 		case TIOCSBRK:
3608 			if (!(async->async_flags & ASYNC_OUT_SUSPEND)) {
3609 				mutex_enter(&asy->asy_excl_hi);
3610 				async->async_flags |= ASYNC_OUT_SUSPEND;
3611 				async->async_flags |= ASYNC_HOLD_UTBRK;
3612 				index = BAUDINDEX(
3613 				    async->async_ttycommon.t_cflag);
3614 				while ((ddi_get8(asy->asy_iohandle,
3615 				    asy->asy_ioaddr + LSR) & XSRE) == 0) {
3616 					mutex_exit(&asy->asy_excl_hi);
3617 					mutex_exit(&asy->asy_excl);
3618 					drv_usecwait(
3619 					    32*asyspdtab[index] & 0xfff);
3620 					mutex_enter(&asy->asy_excl);
3621 					mutex_enter(&asy->asy_excl_hi);
3622 				}
3623 				val = ddi_get8(asy->asy_iohandle,
3624 				    asy->asy_ioaddr + LCR);
3625 				ddi_put8(asy->asy_iohandle,
3626 				    asy->asy_ioaddr + LCR, (val | SETBREAK));
3627 				mutex_exit(&asy->asy_excl_hi);
3628 				/* wait for 100ms to hold BREAK */
3629 				async->async_utbrktid =
3630 				    timeout((void (*)())async_hold_utbrk,
3631 				    (caddr_t)async,
3632 				    drv_usectohz(asy_min_utbrk));
3633 			}
3634 			mioc2ack(mp, NULL, 0, 0);
3635 			break;
3636 
3637 		case TIOCCBRK:
3638 			if (async->async_flags & ASYNC_OUT_SUSPEND)
3639 				async_resume_utbrk(async);
3640 			mioc2ack(mp, NULL, 0, 0);
3641 			break;
3642 
3643 		case TIOCMSET:
3644 		case TIOCMBIS:
3645 		case TIOCMBIC:
3646 			if (iocp->ioc_count != TRANSPARENT) {
3647 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3648 				    "non-transparent\n", instance);
3649 
3650 				error = miocpullup(mp, sizeof (int));
3651 				if (error != 0)
3652 					break;
3653 
3654 				mutex_enter(&asy->asy_excl_hi);
3655 				(void) asymctl(asy,
3656 				    dmtoasy(*(int *)mp->b_cont->b_rptr),
3657 				    iocp->ioc_cmd);
3658 				mutex_exit(&asy->asy_excl_hi);
3659 				iocp->ioc_error = 0;
3660 				mp->b_datap->db_type = M_IOCACK;
3661 			} else {
3662 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3663 				    "transparent\n", instance);
3664 				mcopyin(mp, NULL, sizeof (int), NULL);
3665 			}
3666 			break;
3667 
3668 		case TIOCMGET:
3669 			datamp = allocb(sizeof (int), BPRI_MED);
3670 			if (datamp == NULL) {
3671 				error = EAGAIN;
3672 				break;
3673 			}
3674 
3675 			mutex_enter(&asy->asy_excl_hi);
3676 			*(int *)datamp->b_rptr = asymctl(asy, 0, TIOCMGET);
3677 			mutex_exit(&asy->asy_excl_hi);
3678 
3679 			if (iocp->ioc_count == TRANSPARENT) {
3680 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3681 				    "transparent\n", instance);
3682 				mcopyout(mp, NULL, sizeof (int), NULL, datamp);
3683 			} else {
3684 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3685 				    "non-transparent\n", instance);
3686 				mioc2ack(mp, datamp, sizeof (int), 0);
3687 			}
3688 			break;
3689 
3690 		case CONSOPENPOLLEDIO:
3691 			error = miocpullup(mp, sizeof (struct cons_polledio *));
3692 			if (error != 0)
3693 				break;
3694 
3695 			*(struct cons_polledio **)mp->b_cont->b_rptr =
3696 			    &asy->polledio;
3697 
3698 			mp->b_datap->db_type = M_IOCACK;
3699 			break;
3700 
3701 		case CONSCLOSEPOLLEDIO:
3702 			mp->b_datap->db_type = M_IOCACK;
3703 			iocp->ioc_error = 0;
3704 			iocp->ioc_rval = 0;
3705 			break;
3706 
3707 		case CONSSETABORTENABLE:
3708 			error = secpolicy_console(iocp->ioc_cr);
3709 			if (error != 0)
3710 				break;
3711 
3712 			if (iocp->ioc_count != TRANSPARENT) {
3713 				error = EINVAL;
3714 				break;
3715 			}
3716 
3717 			mutex_enter(&asy->asy_excl_hi);
3718 			if (*(intptr_t *)mp->b_cont->b_rptr)
3719 				asy->asy_flags |= ASY_CONSOLE;
3720 			else
3721 				asy->asy_flags &= ~ASY_CONSOLE;
3722 			mutex_exit(&asy->asy_excl_hi);
3723 
3724 			mp->b_datap->db_type = M_IOCACK;
3725 			iocp->ioc_error = 0;
3726 			iocp->ioc_rval = 0;
3727 			break;
3728 
3729 		case CONSGETABORTENABLE:
3730 			/*CONSTANTCONDITION*/
3731 			ASSERT(sizeof (boolean_t) <= sizeof (boolean_t *));
3732 			/*
3733 			 * Store the return value right in the payload
3734 			 * we were passed.  Crude.
3735 			 */
3736 			mcopyout(mp, NULL, sizeof (boolean_t), NULL, NULL);
3737 			*(boolean_t *)mp->b_cont->b_rptr =
3738 			    (asy->asy_flags & ASY_CONSOLE) != 0;
3739 			break;
3740 
3741 		default:
3742 			/*
3743 			 * If we don't understand it, it's an error.  NAK it.
3744 			 */
3745 			error = EINVAL;
3746 			break;
3747 		}
3748 	}
3749 	if (error != 0) {
3750 		iocp->ioc_error = error;
3751 		mp->b_datap->db_type = M_IOCNAK;
3752 	}
3753 	mutex_exit(&asy->asy_excl);
3754 	qreply(wq, mp);
3755 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_ioctl: done\n", instance);
3756 }
3757 
3758 static int
3759 asyrsrv(queue_t *q)
3760 {
3761 	mblk_t *bp;
3762 	struct asyncline *async;
3763 	struct asycom *asy;
3764 
3765 	async = (struct asyncline *)q->q_ptr;
3766 	asy = (struct asycom *)async->async_common;
3767 
3768 	while (canputnext(q) && (bp = getq(q)))
3769 		putnext(q, bp);
3770 	mutex_enter(&asy->asy_excl_hi);
3771 	ASYSETSOFT(asy);
3772 	mutex_exit(&asy->asy_excl_hi);
3773 	async->async_polltid = 0;
3774 	return (0);
3775 }
3776 
3777 /*
3778  * The ASYWPUTDO_NOT_SUSP macro indicates to asywputdo() whether it should
3779  * handle messages as though the driver is operating normally or is
3780  * suspended.  In the suspended case, some or all of the processing may have
3781  * to be delayed until the driver is resumed.
3782  */
3783 #define	ASYWPUTDO_NOT_SUSP(async, wput) \
3784 	!((wput) && ((async)->async_flags & ASYNC_DDI_SUSPENDED))
3785 
3786 /*
3787  * Processing for write queue put procedure.
3788  * Respond to M_STOP, M_START, M_IOCTL, and M_FLUSH messages here;
3789  * set the flow control character for M_STOPI and M_STARTI messages;
3790  * queue up M_BREAK, M_DELAY, and M_DATA messages for processing
3791  * by the start routine, and then call the start routine; discard
3792  * everything else.  Note that this driver does not incorporate any
3793  * mechanism to negotiate to handle the canonicalization process.
3794  * It expects that these functions are handled in upper module(s),
3795  * as we do in ldterm.
3796  */
3797 static int
3798 asywputdo(queue_t *q, mblk_t *mp, boolean_t wput)
3799 {
3800 	struct asyncline *async;
3801 	struct asycom *asy;
3802 #ifdef DEBUG
3803 	int instance;
3804 #endif
3805 	int error;
3806 
3807 	async = (struct asyncline *)q->q_ptr;
3808 
3809 #ifdef DEBUG
3810 	instance = UNIT(async->async_dev);
3811 #endif
3812 	asy = async->async_common;
3813 
3814 	switch (mp->b_datap->db_type) {
3815 
3816 	case M_STOP:
3817 		/*
3818 		 * Since we don't do real DMA, we can just let the
3819 		 * chip coast to a stop after applying the brakes.
3820 		 */
3821 		mutex_enter(&asy->asy_excl);
3822 		async->async_flags |= ASYNC_STOPPED;
3823 		mutex_exit(&asy->asy_excl);
3824 		freemsg(mp);
3825 		break;
3826 
3827 	case M_START:
3828 		mutex_enter(&asy->asy_excl);
3829 		if (async->async_flags & ASYNC_STOPPED) {
3830 			async->async_flags &= ~ASYNC_STOPPED;
3831 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3832 				/*
3833 				 * If an output operation is in progress,
3834 				 * resume it.  Otherwise, prod the start
3835 				 * routine.
3836 				 */
3837 				if (async->async_ocnt > 0) {
3838 					mutex_enter(&asy->asy_excl_hi);
3839 					async_resume(async);
3840 					mutex_exit(&asy->asy_excl_hi);
3841 				} else {
3842 					async_start(async);
3843 				}
3844 			}
3845 		}
3846 		mutex_exit(&asy->asy_excl);
3847 		freemsg(mp);
3848 		break;
3849 
3850 	case M_IOCTL:
3851 		switch (((struct iocblk *)mp->b_rptr)->ioc_cmd) {
3852 
3853 		case TCSBRK:
3854 			error = miocpullup(mp, sizeof (int));
3855 			if (error != 0) {
3856 				miocnak(q, mp, 0, error);
3857 				return (0);
3858 			}
3859 
3860 			if (*(int *)mp->b_cont->b_rptr != 0) {
3861 				DEBUGCONT1(ASY_DEBUG_OUT,
3862 				    "async%d_ioctl: flush request.\n",
3863 				    instance);
3864 				(void) putq(q, mp);
3865 
3866 				mutex_enter(&asy->asy_excl);
3867 				if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3868 					/*
3869 					 * If an TIOCSBRK is in progress,
3870 					 * clean it as TIOCCBRK does,
3871 					 * then kick off output.
3872 					 * If TIOCSBRK is not in progress,
3873 					 * just kick off output.
3874 					 */
3875 					async_resume_utbrk(async);
3876 				}
3877 				mutex_exit(&asy->asy_excl);
3878 				break;
3879 			}
3880 			/*FALLTHROUGH*/
3881 		case TCSETSW:
3882 		case TCSETSF:
3883 		case TCSETAW:
3884 		case TCSETAF:
3885 			/*
3886 			 * The changes do not take effect until all
3887 			 * output queued before them is drained.
3888 			 * Put this message on the queue, so that
3889 			 * "async_start" will see it when it's done
3890 			 * with the output before it.  Poke the
3891 			 * start routine, just in case.
3892 			 */
3893 			(void) putq(q, mp);
3894 
3895 			mutex_enter(&asy->asy_excl);
3896 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3897 				/*
3898 				 * If an TIOCSBRK is in progress,
3899 				 * clean it as TIOCCBRK does.
3900 				 * then kick off output.
3901 				 * If TIOCSBRK is not in progress,
3902 				 * just kick off output.
3903 				 */
3904 				async_resume_utbrk(async);
3905 			}
3906 			mutex_exit(&asy->asy_excl);
3907 			break;
3908 
3909 		default:
3910 			/*
3911 			 * Do it now.
3912 			 */
3913 			mutex_enter(&asy->asy_excl);
3914 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3915 				mutex_exit(&asy->asy_excl);
3916 				async_ioctl(async, q, mp);
3917 				break;
3918 			}
3919 			async_put_suspq(asy, mp);
3920 			mutex_exit(&asy->asy_excl);
3921 			break;
3922 		}
3923 		break;
3924 
3925 	case M_FLUSH:
3926 		if (*mp->b_rptr & FLUSHW) {
3927 			mutex_enter(&asy->asy_excl);
3928 
3929 			/*
3930 			 * Abort any output in progress.
3931 			 */
3932 			mutex_enter(&asy->asy_excl_hi);
3933 			if (async->async_flags & ASYNC_BUSY) {
3934 				DEBUGCONT1(ASY_DEBUG_BUSY, "asy%dwput: "
3935 				    "Clearing async_ocnt, "
3936 				    "leaving ASYNC_BUSY set\n",
3937 				    instance);
3938 				async->async_ocnt = 0;
3939 				async->async_flags &= ~ASYNC_BUSY;
3940 			} /* if */
3941 
3942 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3943 				/* Flush FIFO buffers */
3944 				if (asy->asy_use_fifo == FIFO_ON) {
3945 					asy_reset_fifo(asy, FIFOTXFLSH);
3946 				}
3947 			}
3948 			mutex_exit(&asy->asy_excl_hi);
3949 
3950 			/* Flush FIFO buffers */
3951 			if (asy->asy_use_fifo == FIFO_ON) {
3952 				asy_reset_fifo(asy, FIFOTXFLSH);
3953 			}
3954 
3955 			/*
3956 			 * Flush our write queue.
3957 			 */
3958 			flushq(q, FLUSHDATA);	/* XXX doesn't flush M_DELAY */
3959 			if (async->async_xmitblk != NULL) {
3960 				freeb(async->async_xmitblk);
3961 				async->async_xmitblk = NULL;
3962 			}
3963 			mutex_exit(&asy->asy_excl);
3964 			*mp->b_rptr &= ~FLUSHW;	/* it has been flushed */
3965 		}
3966 		if (*mp->b_rptr & FLUSHR) {
3967 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3968 				/* Flush FIFO buffers */
3969 				if (asy->asy_use_fifo == FIFO_ON) {
3970 					asy_reset_fifo(asy, FIFORXFLSH);
3971 				}
3972 			}
3973 			flushq(RD(q), FLUSHDATA);
3974 			qreply(q, mp);	/* give the read queues a crack at it */
3975 		} else {
3976 			freemsg(mp);
3977 		}
3978 
3979 		/*
3980 		 * We must make sure we process messages that survive the
3981 		 * write-side flush.
3982 		 */
3983 		if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3984 			mutex_enter(&asy->asy_excl);
3985 			async_start(async);
3986 			mutex_exit(&asy->asy_excl);
3987 		}
3988 		break;
3989 
3990 	case M_BREAK:
3991 	case M_DELAY:
3992 	case M_DATA:
3993 		/*
3994 		 * Queue the message up to be transmitted,
3995 		 * and poke the start routine.
3996 		 */
3997 		(void) putq(q, mp);
3998 		if (ASYWPUTDO_NOT_SUSP(async, wput)) {
3999 			mutex_enter(&asy->asy_excl);
4000 			async_start(async);
4001 			mutex_exit(&asy->asy_excl);
4002 		}
4003 		break;
4004 
4005 	case M_STOPI:
4006 		mutex_enter(&asy->asy_excl);
4007 		if (ASYWPUTDO_NOT_SUSP(async, wput)) {
4008 			mutex_enter(&asy->asy_excl_hi);
4009 			if (!(async->async_inflow_source & IN_FLOW_USER)) {
4010 				async_flowcontrol_hw_input(asy, FLOW_STOP,
4011 				    IN_FLOW_USER);
4012 				(void) async_flowcontrol_sw_input(asy,
4013 				    FLOW_STOP, IN_FLOW_USER);
4014 			}
4015 			mutex_exit(&asy->asy_excl_hi);
4016 			mutex_exit(&asy->asy_excl);
4017 			freemsg(mp);
4018 			break;
4019 		}
4020 		async_put_suspq(asy, mp);
4021 		mutex_exit(&asy->asy_excl);
4022 		break;
4023 
4024 	case M_STARTI:
4025 		mutex_enter(&asy->asy_excl);
4026 		if (ASYWPUTDO_NOT_SUSP(async, wput)) {
4027 			mutex_enter(&asy->asy_excl_hi);
4028 			if (async->async_inflow_source & IN_FLOW_USER) {
4029 				async_flowcontrol_hw_input(asy, FLOW_START,
4030 				    IN_FLOW_USER);
4031 				(void) async_flowcontrol_sw_input(asy,
4032 				    FLOW_START, IN_FLOW_USER);
4033 			}
4034 			mutex_exit(&asy->asy_excl_hi);
4035 			mutex_exit(&asy->asy_excl);
4036 			freemsg(mp);
4037 			break;
4038 		}
4039 		async_put_suspq(asy, mp);
4040 		mutex_exit(&asy->asy_excl);
4041 		break;
4042 
4043 	case M_CTL:
4044 		if (MBLKL(mp) >= sizeof (struct iocblk) &&
4045 		    ((struct iocblk *)mp->b_rptr)->ioc_cmd == MC_POSIXQUERY) {
4046 			mutex_enter(&asy->asy_excl);
4047 			if (ASYWPUTDO_NOT_SUSP(async, wput)) {
4048 				((struct iocblk *)mp->b_rptr)->ioc_cmd =
4049 				    MC_HAS_POSIX;
4050 				mutex_exit(&asy->asy_excl);
4051 				qreply(q, mp);
4052 				break;
4053 			} else {
4054 				async_put_suspq(asy, mp);
4055 			}
4056 		} else {
4057 			/*
4058 			 * These MC_SERVICE type messages are used by upper
4059 			 * modules to tell this driver to send input up
4060 			 * immediately, or that it can wait for normal
4061 			 * processing that may or may not be done.  Sun
4062 			 * requires these for the mouse module.
4063 			 * (XXX - for x86?)
4064 			 */
4065 			mutex_enter(&asy->asy_excl);
4066 			switch (*mp->b_rptr) {
4067 
4068 			case MC_SERVICEIMM:
4069 				async->async_flags |= ASYNC_SERVICEIMM;
4070 				break;
4071 
4072 			case MC_SERVICEDEF:
4073 				async->async_flags &= ~ASYNC_SERVICEIMM;
4074 				break;
4075 			}
4076 			mutex_exit(&asy->asy_excl);
4077 			freemsg(mp);
4078 		}
4079 		break;
4080 
4081 	case M_IOCDATA:
4082 		mutex_enter(&asy->asy_excl);
4083 		if (ASYWPUTDO_NOT_SUSP(async, wput)) {
4084 			mutex_exit(&asy->asy_excl);
4085 			async_iocdata(q, mp);
4086 			break;
4087 		}
4088 		async_put_suspq(asy, mp);
4089 		mutex_exit(&asy->asy_excl);
4090 		break;
4091 
4092 	default:
4093 		freemsg(mp);
4094 		break;
4095 	}
4096 	return (0);
4097 }
4098 
4099 static int
4100 asywput(queue_t *q, mblk_t *mp)
4101 {
4102 	return (asywputdo(q, mp, B_TRUE));
4103 }
4104 
4105 /*
4106  * Retry an "ioctl", now that "bufcall" claims we may be able to allocate
4107  * the buffer we need.
4108  */
4109 static void
4110 async_reioctl(void *unit)
4111 {
4112 	int instance = (uintptr_t)unit;
4113 	struct asyncline *async;
4114 	struct asycom *asy;
4115 	queue_t	*q;
4116 	mblk_t	*mp;
4117 
4118 	asy = ddi_get_soft_state(asy_soft_state, instance);
4119 	ASSERT(asy != NULL);
4120 	async = asy->asy_priv;
4121 
4122 	/*
4123 	 * The bufcall is no longer pending.
4124 	 */
4125 	mutex_enter(&asy->asy_excl);
4126 	async->async_wbufcid = 0;
4127 	if ((q = async->async_ttycommon.t_writeq) == NULL) {
4128 		mutex_exit(&asy->asy_excl);
4129 		return;
4130 	}
4131 	if ((mp = async->async_ttycommon.t_iocpending) != NULL) {
4132 		/* not pending any more */
4133 		async->async_ttycommon.t_iocpending = NULL;
4134 		mutex_exit(&asy->asy_excl);
4135 		async_ioctl(async, q, mp);
4136 	} else
4137 		mutex_exit(&asy->asy_excl);
4138 }
4139 
4140 static void
4141 async_iocdata(queue_t *q, mblk_t *mp)
4142 {
4143 	struct asyncline	*async = (struct asyncline *)q->q_ptr;
4144 	struct asycom		*asy;
4145 	struct iocblk *ip;
4146 	struct copyresp *csp;
4147 #ifdef DEBUG
4148 	int instance = UNIT(async->async_dev);
4149 #endif
4150 
4151 	asy = async->async_common;
4152 	ip = (struct iocblk *)mp->b_rptr;
4153 	csp = (struct copyresp *)mp->b_rptr;
4154 
4155 	if (csp->cp_rval != 0) {
4156 		if (csp->cp_private)
4157 			freemsg(csp->cp_private);
4158 		freemsg(mp);
4159 		return;
4160 	}
4161 
4162 	mutex_enter(&asy->asy_excl);
4163 	DEBUGCONT2(ASY_DEBUG_MODEM, "async%d_iocdata: case %s\n",
4164 	    instance,
4165 	    csp->cp_cmd == TIOCMGET ? "TIOCMGET" :
4166 	    csp->cp_cmd == TIOCMSET ? "TIOCMSET" :
4167 	    csp->cp_cmd == TIOCMBIS ? "TIOCMBIS" :
4168 	    "TIOCMBIC");
4169 	switch (csp->cp_cmd) {
4170 
4171 	case TIOCMGET:
4172 		if (mp->b_cont) {
4173 			freemsg(mp->b_cont);
4174 			mp->b_cont = NULL;
4175 		}
4176 		mp->b_datap->db_type = M_IOCACK;
4177 		ip->ioc_error = 0;
4178 		ip->ioc_count = 0;
4179 		ip->ioc_rval = 0;
4180 		mp->b_wptr = mp->b_rptr + sizeof (struct iocblk);
4181 		break;
4182 
4183 	case TIOCMSET:
4184 	case TIOCMBIS:
4185 	case TIOCMBIC:
4186 		mutex_enter(&asy->asy_excl_hi);
4187 		(void) asymctl(asy, dmtoasy(*(int *)mp->b_cont->b_rptr),
4188 		    csp->cp_cmd);
4189 		mutex_exit(&asy->asy_excl_hi);
4190 		mioc2ack(mp, NULL, 0, 0);
4191 		break;
4192 
4193 	default:
4194 		mp->b_datap->db_type = M_IOCNAK;
4195 		ip->ioc_error = EINVAL;
4196 		break;
4197 	}
4198 	qreply(q, mp);
4199 	mutex_exit(&asy->asy_excl);
4200 }
4201 
4202 /*
4203  * debugger/console support routines.
4204  */
4205 
4206 /*
4207  * put a character out
4208  * Do not use interrupts.  If char is LF, put out CR, LF.
4209  */
4210 static void
4211 asyputchar(cons_polledio_arg_t arg, uchar_t c)
4212 {
4213 	struct asycom *asy = (struct asycom *)arg;
4214 
4215 	if (c == '\n')
4216 		asyputchar(arg, '\r');
4217 
4218 	while ((ddi_get8(asy->asy_iohandle,
4219 	    asy->asy_ioaddr + LSR) & XHRE) == 0) {
4220 		/* wait for xmit to finish */
4221 		drv_usecwait(10);
4222 	}
4223 
4224 	/* put the character out */
4225 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT, c);
4226 }
4227 
4228 /*
4229  * See if there's a character available. If no character is
4230  * available, return 0. Run in polled mode, no interrupts.
4231  */
4232 static boolean_t
4233 asyischar(cons_polledio_arg_t arg)
4234 {
4235 	struct asycom *asy = (struct asycom *)arg;
4236 
4237 	return ((ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR) & RCA)
4238 	    != 0);
4239 }
4240 
4241 /*
4242  * Get a character. Run in polled mode, no interrupts.
4243  */
4244 static int
4245 asygetchar(cons_polledio_arg_t arg)
4246 {
4247 	struct asycom *asy = (struct asycom *)arg;
4248 
4249 	while (!asyischar(arg))
4250 		drv_usecwait(10);
4251 	return (ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + DAT));
4252 }
4253 
4254 /*
4255  * Set or get the modem control status.
4256  */
4257 static int
4258 asymctl(struct asycom *asy, int bits, int how)
4259 {
4260 	int mcr_r, msr_r;
4261 	int instance = asy->asy_unit;
4262 
4263 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4264 	ASSERT(mutex_owned(&asy->asy_excl));
4265 
4266 	/* Read Modem Control Registers */
4267 	mcr_r = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
4268 
4269 	switch (how) {
4270 
4271 	case TIOCMSET:
4272 		DEBUGCONT2(ASY_DEBUG_MODEM,
4273 		    "asy%dmctl: TIOCMSET, bits = %x\n", instance, bits);
4274 		mcr_r = bits;		/* Set bits	*/
4275 		break;
4276 
4277 	case TIOCMBIS:
4278 		DEBUGCONT2(ASY_DEBUG_MODEM, "asy%dmctl: TIOCMBIS, bits = %x\n",
4279 		    instance, bits);
4280 		mcr_r |= bits;		/* Mask in bits	*/
4281 		break;
4282 
4283 	case TIOCMBIC:
4284 		DEBUGCONT2(ASY_DEBUG_MODEM, "asy%dmctl: TIOCMBIC, bits = %x\n",
4285 		    instance, bits);
4286 		mcr_r &= ~bits;		/* Mask out bits */
4287 		break;
4288 
4289 	case TIOCMGET:
4290 		/* Read Modem Status Registers */
4291 		/*
4292 		 * If modem interrupts are enabled, we return the
4293 		 * saved value of msr. We read MSR only in async_msint()
4294 		 */
4295 		if (ddi_get8(asy->asy_iohandle,
4296 		    asy->asy_ioaddr + ICR) & MIEN) {
4297 			msr_r = asy->asy_msr;
4298 			DEBUGCONT2(ASY_DEBUG_MODEM,
4299 			    "asy%dmctl: TIOCMGET, read msr_r = %x\n",
4300 			    instance, msr_r);
4301 		} else {
4302 			msr_r = ddi_get8(asy->asy_iohandle,
4303 			    asy->asy_ioaddr + MSR);
4304 			DEBUGCONT2(ASY_DEBUG_MODEM,
4305 			    "asy%dmctl: TIOCMGET, read MSR = %x\n",
4306 			    instance, msr_r);
4307 		}
4308 		DEBUGCONT2(ASY_DEBUG_MODEM, "asy%dtodm: modem_lines = %x\n",
4309 		    instance, asytodm(mcr_r, msr_r));
4310 		return (asytodm(mcr_r, msr_r));
4311 	}
4312 
4313 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR, mcr_r);
4314 
4315 	return (mcr_r);
4316 }
4317 
4318 static int
4319 asytodm(int mcr_r, int msr_r)
4320 {
4321 	int b = 0;
4322 
4323 	/* MCR registers */
4324 	if (mcr_r & RTS)
4325 		b |= TIOCM_RTS;
4326 
4327 	if (mcr_r & DTR)
4328 		b |= TIOCM_DTR;
4329 
4330 	/* MSR registers */
4331 	if (msr_r & DCD)
4332 		b |= TIOCM_CAR;
4333 
4334 	if (msr_r & CTS)
4335 		b |= TIOCM_CTS;
4336 
4337 	if (msr_r & DSR)
4338 		b |= TIOCM_DSR;
4339 
4340 	if (msr_r & RI)
4341 		b |= TIOCM_RNG;
4342 	return (b);
4343 }
4344 
4345 static int
4346 dmtoasy(int bits)
4347 {
4348 	int b = 0;
4349 
4350 	DEBUGCONT1(ASY_DEBUG_MODEM, "dmtoasy: bits = %x\n", bits);
4351 #ifdef	CAN_NOT_SET	/* only DTR and RTS can be set */
4352 	if (bits & TIOCM_CAR)
4353 		b |= DCD;
4354 	if (bits & TIOCM_CTS)
4355 		b |= CTS;
4356 	if (bits & TIOCM_DSR)
4357 		b |= DSR;
4358 	if (bits & TIOCM_RNG)
4359 		b |= RI;
4360 #endif
4361 
4362 	if (bits & TIOCM_RTS) {
4363 		DEBUGCONT0(ASY_DEBUG_MODEM, "dmtoasy: set b & RTS\n");
4364 		b |= RTS;
4365 	}
4366 	if (bits & TIOCM_DTR) {
4367 		DEBUGCONT0(ASY_DEBUG_MODEM, "dmtoasy: set b & DTR\n");
4368 		b |= DTR;
4369 	}
4370 
4371 	return (b);
4372 }
4373 
4374 static void
4375 asyerror(int level, const char *fmt, ...)
4376 {
4377 	va_list adx;
4378 	static	time_t	last;
4379 	static	const char *lastfmt;
4380 	time_t	now;
4381 
4382 	/*
4383 	 * Don't print the same error message too often.
4384 	 * Print the message only if we have not printed the
4385 	 * message within the last second.
4386 	 * Note: that fmt cannot be a pointer to a string
4387 	 * stored on the stack. The fmt pointer
4388 	 * must be in the data segment otherwise lastfmt would point
4389 	 * to non-sense.
4390 	 */
4391 	now = gethrestime_sec();
4392 	if (last == now && lastfmt == fmt)
4393 		return;
4394 
4395 	last = now;
4396 	lastfmt = fmt;
4397 
4398 	va_start(adx, fmt);
4399 	vcmn_err(level, fmt, adx);
4400 	va_end(adx);
4401 }
4402 
4403 /*
4404  * asy_parse_mode(dev_info_t *devi, struct asycom *asy)
4405  * The value of this property is in the form of "9600,8,n,1,-"
4406  * 1) speed: 9600, 4800, ...
4407  * 2) data bits
4408  * 3) parity: n(none), e(even), o(odd)
4409  * 4) stop bits
4410  * 5) handshake: -(none), h(hardware: rts/cts), s(software: xon/off)
4411  *
4412  * This parsing came from a SPARCstation eeprom.
4413  */
4414 static void
4415 asy_parse_mode(dev_info_t *devi, struct asycom *asy)
4416 {
4417 	char		name[40];
4418 	char		val[40];
4419 	int		len;
4420 	int		ret;
4421 	char		*p;
4422 	char		*p1;
4423 
4424 	ASSERT(asy->asy_com_port != 0);
4425 
4426 	/*
4427 	 * Parse the ttyx-mode property
4428 	 */
4429 	(void) sprintf(name, "tty%c-mode", asy->asy_com_port + 'a' - 1);
4430 	len = sizeof (val);
4431 	ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
4432 	if (ret != DDI_PROP_SUCCESS) {
4433 		(void) sprintf(name, "com%c-mode", asy->asy_com_port + '0');
4434 		len = sizeof (val);
4435 		ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
4436 	}
4437 
4438 	/* no property to parse */
4439 	asy->asy_cflag = 0;
4440 	if (ret != DDI_PROP_SUCCESS)
4441 		return;
4442 
4443 	p = val;
4444 	/* ---- baud rate ---- */
4445 	asy->asy_cflag = CREAD|B9600;		/* initial default */
4446 	if (p && (p1 = strchr(p, ',')) != 0) {
4447 		*p1++ = '\0';
4448 	} else {
4449 		asy->asy_cflag |= BITS8;	/* add default bits */
4450 		return;
4451 	}
4452 
4453 	if (strcmp(p, "110") == 0)
4454 		asy->asy_bidx = B110;
4455 	else if (strcmp(p, "150") == 0)
4456 		asy->asy_bidx = B150;
4457 	else if (strcmp(p, "300") == 0)
4458 		asy->asy_bidx = B300;
4459 	else if (strcmp(p, "600") == 0)
4460 		asy->asy_bidx = B600;
4461 	else if (strcmp(p, "1200") == 0)
4462 		asy->asy_bidx = B1200;
4463 	else if (strcmp(p, "2400") == 0)
4464 		asy->asy_bidx = B2400;
4465 	else if (strcmp(p, "4800") == 0)
4466 		asy->asy_bidx = B4800;
4467 	else if (strcmp(p, "9600") == 0)
4468 		asy->asy_bidx = B9600;
4469 	else if (strcmp(p, "19200") == 0)
4470 		asy->asy_bidx = B19200;
4471 	else if (strcmp(p, "38400") == 0)
4472 		asy->asy_bidx = B38400;
4473 	else if (strcmp(p, "57600") == 0)
4474 		asy->asy_bidx = B57600;
4475 	else if (strcmp(p, "115200") == 0)
4476 		asy->asy_bidx = B115200;
4477 	else
4478 		asy->asy_bidx = B9600;
4479 
4480 	asy->asy_cflag &= ~CBAUD;
4481 	if (asy->asy_bidx > CBAUD) {	/* > 38400 uses the CBAUDEXT bit */
4482 		asy->asy_cflag |= CBAUDEXT;
4483 		asy->asy_cflag |= asy->asy_bidx - CBAUD - 1;
4484 	} else {
4485 		asy->asy_cflag |= asy->asy_bidx;
4486 	}
4487 
4488 	ASSERT(asy->asy_bidx == BAUDINDEX(asy->asy_cflag));
4489 
4490 	/* ---- Next item is data bits ---- */
4491 	p = p1;
4492 	if (p && (p1 = strchr(p, ',')) != 0)  {
4493 		*p1++ = '\0';
4494 	} else {
4495 		asy->asy_cflag |= BITS8;	/* add default bits */
4496 		return;
4497 	}
4498 	switch (*p) {
4499 		default:
4500 		case '8':
4501 			asy->asy_cflag |= CS8;
4502 			asy->asy_lcr = BITS8;
4503 			break;
4504 		case '7':
4505 			asy->asy_cflag |= CS7;
4506 			asy->asy_lcr = BITS7;
4507 			break;
4508 		case '6':
4509 			asy->asy_cflag |= CS6;
4510 			asy->asy_lcr = BITS6;
4511 			break;
4512 		case '5':
4513 			/* LINTED: CS5 is currently zero (but might change) */
4514 			asy->asy_cflag |= CS5;
4515 			asy->asy_lcr = BITS5;
4516 			break;
4517 	}
4518 
4519 	/* ---- Parity info ---- */
4520 	p = p1;
4521 	if (p && (p1 = strchr(p, ',')) != 0)  {
4522 		*p1++ = '\0';
4523 	} else {
4524 		return;
4525 	}
4526 	switch (*p)  {
4527 		default:
4528 		case 'n':
4529 			break;
4530 		case 'e':
4531 			asy->asy_cflag |= PARENB;
4532 			asy->asy_lcr |= PEN; break;
4533 		case 'o':
4534 			asy->asy_cflag |= PARENB|PARODD;
4535 			asy->asy_lcr |= PEN|EPS;
4536 			break;
4537 	}
4538 
4539 	/* ---- Find stop bits ---- */
4540 	p = p1;
4541 	if (p && (p1 = strchr(p, ',')) != 0)  {
4542 		*p1++ = '\0';
4543 	} else {
4544 		return;
4545 	}
4546 	if (*p == '2') {
4547 		asy->asy_cflag |= CSTOPB;
4548 		asy->asy_lcr |= STB;
4549 	}
4550 
4551 	/* ---- handshake is next ---- */
4552 	p = p1;
4553 	if (p) {
4554 		if ((p1 = strchr(p, ',')) != 0)
4555 			*p1++ = '\0';
4556 
4557 		if (*p == 'h')
4558 			asy->asy_cflag |= CRTSCTS;
4559 		else if (*p == 's')
4560 			asy->asy_cflag |= CRTSXOFF;
4561 	}
4562 }
4563 
4564 /*
4565  * Check for abort character sequence
4566  */
4567 static boolean_t
4568 abort_charseq_recognize(uchar_t ch)
4569 {
4570 	static int state = 0;
4571 #define	CNTRL(c) ((c)&037)
4572 	static char sequence[] = { '\r', '~', CNTRL('b') };
4573 
4574 	if (ch == sequence[state]) {
4575 		if (++state >= sizeof (sequence)) {
4576 			state = 0;
4577 			return (B_TRUE);
4578 		}
4579 	} else {
4580 		state = (ch == sequence[0]) ? 1 : 0;
4581 	}
4582 	return (B_FALSE);
4583 }
4584 
4585 /*
4586  * Flow control functions
4587  */
4588 /*
4589  * Software input flow control
4590  * This function can execute software input flow control sucessfully
4591  * at most of situations except that the line is in BREAK status
4592  * (timed and untimed break).
4593  * INPUT VALUE of onoff:
4594  *               FLOW_START means to send out a XON char
4595  *                          and clear SW input flow control flag.
4596  *               FLOW_STOP means to send out a XOFF char
4597  *                          and set SW input flow control flag.
4598  *               FLOW_CHECK means to check whether there is pending XON/XOFF
4599  *                          if it is true, send it out.
4600  * INPUT VALUE of type:
4601  *		 IN_FLOW_RINGBUFF means flow control is due to RING BUFFER
4602  *		 IN_FLOW_STREAMS means flow control is due to STREAMS
4603  *		 IN_FLOW_USER means flow control is due to user's commands
4604  * RETURN VALUE: B_FALSE means no flow control char is sent
4605  *               B_TRUE means one flow control char is sent
4606  */
4607 static boolean_t
4608 async_flowcontrol_sw_input(struct asycom *asy, async_flowc_action onoff,
4609     int type)
4610 {
4611 	struct asyncline *async = asy->asy_priv;
4612 	int instance = UNIT(async->async_dev);
4613 	int rval = B_FALSE;
4614 
4615 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4616 
4617 	if (!(async->async_ttycommon.t_iflag & IXOFF))
4618 		return (rval);
4619 
4620 	/*
4621 	 * If we get this far, then we know IXOFF is set.
4622 	 */
4623 	switch (onoff) {
4624 	case FLOW_STOP:
4625 		async->async_inflow_source |= type;
4626 
4627 		/*
4628 		 * We'll send an XOFF character for each of up to
4629 		 * three different input flow control attempts to stop input.
4630 		 * If we already send out one XOFF, but FLOW_STOP comes again,
4631 		 * it seems that input flow control becomes more serious,
4632 		 * then send XOFF again.
4633 		 */
4634 		if (async->async_inflow_source & (IN_FLOW_RINGBUFF |
4635 		    IN_FLOW_STREAMS | IN_FLOW_USER))
4636 			async->async_flags |= ASYNC_SW_IN_FLOW |
4637 			    ASYNC_SW_IN_NEEDED;
4638 		DEBUGCONT2(ASY_DEBUG_SFLOW, "async%d: input sflow stop, "
4639 		    "type = %x\n", instance, async->async_inflow_source);
4640 		break;
4641 	case FLOW_START:
4642 		async->async_inflow_source &= ~type;
4643 		if (async->async_inflow_source == 0) {
4644 			async->async_flags = (async->async_flags &
4645 			    ~ASYNC_SW_IN_FLOW) | ASYNC_SW_IN_NEEDED;
4646 			DEBUGCONT1(ASY_DEBUG_SFLOW, "async%d: "
4647 			    "input sflow start\n", instance);
4648 		}
4649 		break;
4650 	default:
4651 		break;
4652 	}
4653 
4654 	if (((async->async_flags & (ASYNC_SW_IN_NEEDED | ASYNC_BREAK |
4655 	    ASYNC_OUT_SUSPEND)) == ASYNC_SW_IN_NEEDED) &&
4656 	    (ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR) & XHRE)) {
4657 		/*
4658 		 * If we get this far, then we know we need to send out
4659 		 * XON or XOFF char.
4660 		 */
4661 		async->async_flags = (async->async_flags &
4662 		    ~ASYNC_SW_IN_NEEDED) | ASYNC_BUSY;
4663 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
4664 		    async->async_flags & ASYNC_SW_IN_FLOW ?
4665 		    async->async_stopc : async->async_startc);
4666 		rval = B_TRUE;
4667 	}
4668 	return (rval);
4669 }
4670 
4671 /*
4672  * Software output flow control
4673  * This function can be executed sucessfully at any situation.
4674  * It does not handle HW, and just change the SW output flow control flag.
4675  * INPUT VALUE of onoff:
4676  *                 FLOW_START means to clear SW output flow control flag,
4677  *			also combine with HW output flow control status to
4678  *			determine if we need to set ASYNC_OUT_FLW_RESUME.
4679  *                 FLOW_STOP means to set SW output flow control flag,
4680  *			also clear ASYNC_OUT_FLW_RESUME.
4681  */
4682 static void
4683 async_flowcontrol_sw_output(struct asycom *asy, async_flowc_action onoff)
4684 {
4685 	struct asyncline *async = asy->asy_priv;
4686 	int instance = UNIT(async->async_dev);
4687 
4688 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4689 
4690 	if (!(async->async_ttycommon.t_iflag & IXON))
4691 		return;
4692 
4693 	switch (onoff) {
4694 	case FLOW_STOP:
4695 		async->async_flags |= ASYNC_SW_OUT_FLW;
4696 		async->async_flags &= ~ASYNC_OUT_FLW_RESUME;
4697 		DEBUGCONT1(ASY_DEBUG_SFLOW, "async%d: output sflow stop\n",
4698 		    instance);
4699 		break;
4700 	case FLOW_START:
4701 		async->async_flags &= ~ASYNC_SW_OUT_FLW;
4702 		if (!(async->async_flags & ASYNC_HW_OUT_FLW))
4703 			async->async_flags |= ASYNC_OUT_FLW_RESUME;
4704 		DEBUGCONT1(ASY_DEBUG_SFLOW, "async%d: output sflow start\n",
4705 		    instance);
4706 		break;
4707 	default:
4708 		break;
4709 	}
4710 }
4711 
4712 /*
4713  * Hardware input flow control
4714  * This function can be executed sucessfully at any situation.
4715  * It directly changes RTS depending on input parameter onoff.
4716  * INPUT VALUE of onoff:
4717  *       FLOW_START means to clear HW input flow control flag,
4718  *                  and pull up RTS if it is low.
4719  *       FLOW_STOP means to set HW input flow control flag,
4720  *                  and low RTS if it is high.
4721  * INPUT VALUE of type:
4722  *		 IN_FLOW_RINGBUFF means flow control is due to RING BUFFER
4723  *		 IN_FLOW_STREAMS means flow control is due to STREAMS
4724  *		 IN_FLOW_USER means flow control is due to user's commands
4725  */
4726 static void
4727 async_flowcontrol_hw_input(struct asycom *asy, async_flowc_action onoff,
4728     int type)
4729 {
4730 	uchar_t	mcr;
4731 	uchar_t	flag;
4732 	struct asyncline *async = asy->asy_priv;
4733 	int instance = UNIT(async->async_dev);
4734 
4735 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4736 
4737 	if (!(async->async_ttycommon.t_cflag & CRTSXOFF))
4738 		return;
4739 
4740 	switch (onoff) {
4741 	case FLOW_STOP:
4742 		async->async_inflow_source |= type;
4743 		if (async->async_inflow_source & (IN_FLOW_RINGBUFF |
4744 		    IN_FLOW_STREAMS | IN_FLOW_USER))
4745 			async->async_flags |= ASYNC_HW_IN_FLOW;
4746 		DEBUGCONT2(ASY_DEBUG_HFLOW, "async%d: input hflow stop, "
4747 		    "type = %x\n", instance, async->async_inflow_source);
4748 		break;
4749 	case FLOW_START:
4750 		async->async_inflow_source &= ~type;
4751 		if (async->async_inflow_source == 0) {
4752 			async->async_flags &= ~ASYNC_HW_IN_FLOW;
4753 			DEBUGCONT1(ASY_DEBUG_HFLOW, "async%d: "
4754 			    "input hflow start\n", instance);
4755 		}
4756 		break;
4757 	default:
4758 		break;
4759 	}
4760 	mcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
4761 	flag = (async->async_flags & ASYNC_HW_IN_FLOW) ? 0 : RTS;
4762 
4763 	if (((mcr ^ flag) & RTS) != 0) {
4764 		ddi_put8(asy->asy_iohandle,
4765 		    asy->asy_ioaddr + MCR, (mcr ^ RTS));
4766 	}
4767 }
4768 
4769 /*
4770  * Hardware output flow control
4771  * This function can execute HW output flow control sucessfully
4772  * at any situation.
4773  * It doesn't really change RTS, and just change
4774  * HW output flow control flag depending on CTS status.
4775  * INPUT VALUE of onoff:
4776  *                FLOW_START means to clear HW output flow control flag.
4777  *			also combine with SW output flow control status to
4778  *			determine if we need to set ASYNC_OUT_FLW_RESUME.
4779  *                FLOW_STOP means to set HW output flow control flag.
4780  *			also clear ASYNC_OUT_FLW_RESUME.
4781  */
4782 static void
4783 async_flowcontrol_hw_output(struct asycom *asy, async_flowc_action onoff)
4784 {
4785 	struct asyncline *async = asy->asy_priv;
4786 	int instance = UNIT(async->async_dev);
4787 
4788 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4789 
4790 	if (!(async->async_ttycommon.t_cflag & CRTSCTS))
4791 		return;
4792 
4793 	switch (onoff) {
4794 	case FLOW_STOP:
4795 		async->async_flags |= ASYNC_HW_OUT_FLW;
4796 		async->async_flags &= ~ASYNC_OUT_FLW_RESUME;
4797 		DEBUGCONT1(ASY_DEBUG_HFLOW, "async%d: output hflow stop\n",
4798 		    instance);
4799 		break;
4800 	case FLOW_START:
4801 		async->async_flags &= ~ASYNC_HW_OUT_FLW;
4802 		if (!(async->async_flags & ASYNC_SW_OUT_FLW))
4803 			async->async_flags |= ASYNC_OUT_FLW_RESUME;
4804 		DEBUGCONT1(ASY_DEBUG_HFLOW, "async%d: output hflow start\n",
4805 		    instance);
4806 		break;
4807 	default:
4808 		break;
4809 	}
4810 }
4811 
4812 
4813 /*
4814  * quiesce(9E) entry point.
4815  *
4816  * This function is called when the system is single-threaded at high
4817  * PIL with preemption disabled. Therefore, this function must not be
4818  * blocked.
4819  *
4820  * This function returns DDI_SUCCESS on success, or DDI_FAILURE on failure.
4821  * DDI_FAILURE indicates an error condition and should almost never happen.
4822  */
4823 static int
4824 asyquiesce(dev_info_t *devi)
4825 {
4826 	int instance;
4827 	struct asycom *asy;
4828 
4829 	instance = ddi_get_instance(devi);	/* find out which unit */
4830 
4831 	asy = ddi_get_soft_state(asy_soft_state, instance);
4832 	if (asy == NULL)
4833 		return (DDI_FAILURE);
4834 
4835 	/* disable all interrupts */
4836 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
4837 
4838 	/* reset the FIFO */
4839 	asy_reset_fifo(asy, FIFOTXFLSH | FIFORXFLSH);
4840 
4841 	return (DDI_SUCCESS);
4842 }
4843