xref: /titanic_51/usr/src/uts/common/io/asy.c (revision 42487ff1899d230ad6c2d55cf9573489ca5eb770)
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 2005 Sun Microsystems, Inc.  All rights reserved.
28  * Use is subject to license terms.
29  */
30 
31 #pragma ident	"%Z%%M%	%I%	%E% SMI"
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/asy.h>
64 #include <sys/policy.h>
65 
66 /*
67  * set the RX FIFO trigger_level to half the RX FIFO size for now
68  * we may want to make this configurable later.
69  */
70 static	int asy_trig_level = FIFO_TRIG_8;
71 
72 int asy_drain_check = 15000000;		/* tunable: exit drain check time */
73 int asy_min_dtr_low = 500000;		/* tunable: minimum DTR down time */
74 int asy_min_utbrk = 100000;		/* tunable: minumum untimed brk time */
75 
76 int asymaxchip = ASY16750;	/* tunable: limit chip support we look for */
77 
78 /*
79  * Just in case someone has a chip with broken loopback mode, we provide a
80  * means to disable the loopback test. By default, we only loopback test
81  * UARTs which look like they have FIFOs bigger than 16 bytes.
82  * Set to 0 to suppress test, or to 2 to enable test on any size FIFO.
83  */
84 int asy_fifo_test = 1;		/* tunable: set to 0, 1, or 2 */
85 
86 /*
87  * Allow ability to switch off testing of the scratch register.
88  * Some UART emulators might not have it. This will also disable the test
89  * for Exar/Startech ST16C650, as that requires use of the SCR register.
90  */
91 int asy_scr_test = 1;		/* tunable: set to 0 to disable SCR reg test */
92 
93 /*
94  * As we don't yet support on-chip flow control, it's a bad idea to put a
95  * large number of characters in the TX FIFO, since if other end tells us
96  * to stop transmitting, we can only stop filling the TX FIFO, but it will
97  * still carry on draining by itself, so remote end still gets what's left
98  * in the FIFO.
99  */
100 int asy_max_tx_fifo = 16;	/* tunable: max fill of TX FIFO */
101 
102 #define	async_stopc	async_ttycommon.t_stopc
103 #define	async_startc	async_ttycommon.t_startc
104 
105 #define	ASY_INIT	1
106 #define	ASY_NOINIT	0
107 
108 /* enum value for sw and hw flow control action */
109 typedef enum {
110 	FLOW_CHECK,
111 	FLOW_STOP,
112 	FLOW_START
113 } async_flowc_action;
114 
115 #ifdef DEBUG
116 #define	ASY_DEBUG_INIT	0x0001	/* Output msgs during driver initialization. */
117 #define	ASY_DEBUG_INPUT	0x0002	/* Report characters received during int. */
118 #define	ASY_DEBUG_EOT	0x0004	/* Output msgs when wait for xmit to finish. */
119 #define	ASY_DEBUG_CLOSE	0x0008	/* Output msgs when driver open/close called */
120 #define	ASY_DEBUG_HFLOW	0x0010	/* Output msgs when H/W flowcontrol is active */
121 #define	ASY_DEBUG_PROCS	0x0020	/* Output each proc name as it is entered. */
122 #define	ASY_DEBUG_STATE	0x0040	/* Output value of Interrupt Service Reg. */
123 #define	ASY_DEBUG_INTR	0x0080	/* Output value of Interrupt Service Reg. */
124 #define	ASY_DEBUG_OUT	0x0100	/* Output msgs about output events. */
125 #define	ASY_DEBUG_BUSY	0x0200	/* Output msgs when xmit is enabled/disabled */
126 #define	ASY_DEBUG_MODEM	0x0400	/* Output msgs about modem status & control. */
127 #define	ASY_DEBUG_MODM2	0x0800	/* Output msgs about modem status & control. */
128 #define	ASY_DEBUG_IOCTL	0x1000	/* Output msgs about ioctl messages. */
129 #define	ASY_DEBUG_CHIP	0x2000	/* Output msgs about chip identification. */
130 #define	ASY_DEBUG_SFLOW	0x4000	/* Output msgs when S/W flowcontrol is active */
131 #define	ASY_DEBUG(x) (debug & (x))
132 static	int debug  = 0;
133 #else
134 #define	ASY_DEBUG(x) B_FALSE
135 #endif
136 
137 /* pnpISA compressed device ids */
138 #define	pnpMTS0219 0xb6930219	/* Multitech MT5634ZTX modem */
139 
140 /*
141  * PPS (Pulse Per Second) support.
142  */
143 void ddi_hardpps();
144 /*
145  * This is protected by the asy_excl_hi of the port on which PPS event
146  * handling is enabled.  Note that only one port should have this enabled at
147  * any one time.  Enabling PPS handling on multiple ports will result in
148  * unpredictable (but benign) results.
149  */
150 static struct ppsclockev asy_ppsev;
151 
152 #ifdef PPSCLOCKLED
153 /* XXX Use these to observe PPS latencies and jitter on a scope */
154 #define	LED_ON
155 #define	LED_OFF
156 #else
157 #define	LED_ON
158 #define	LED_OFF
159 #endif
160 
161 static	int max_asy_instance = -1;
162 
163 static	uint_t	asysoftintr(caddr_t intarg);
164 static	uint_t	asyintr(caddr_t argasy);
165 
166 static boolean_t abort_charseq_recognize(uchar_t ch);
167 
168 /* The async interrupt entry points */
169 static void	async_txint(struct asycom *asy);
170 static void	async_rxint(struct asycom *asy, uchar_t lsr);
171 static void	async_msint(struct asycom *asy);
172 static void	async_softint(struct asycom *asy);
173 
174 static void	async_ioctl(struct asyncline *async, queue_t *q, mblk_t *mp);
175 static void	async_reioctl(void *unit);
176 static void	async_iocdata(queue_t *q, mblk_t *mp);
177 static void	async_restart(void *arg);
178 static void	async_start(struct asyncline *async);
179 static void	async_nstart(struct asyncline *async, int mode);
180 static void	async_resume(struct asyncline *async);
181 static void	asy_program(struct asycom *asy, int mode);
182 static void	asyinit(struct asycom *asy);
183 static void	asy_waiteot(struct asycom *asy);
184 static void	asyputchar(struct cons_polledio_arg *, uchar_t c);
185 static int	asygetchar(struct cons_polledio_arg *);
186 static boolean_t	asyischar(struct cons_polledio_arg *);
187 
188 static int	asymctl(struct asycom *, int, int);
189 static int	asytodm(int, int);
190 static int	dmtoasy(int);
191 /*PRINTFLIKE2*/
192 static void	asyerror(int level, const char *fmt, ...) __KPRINTFLIKE(2);
193 static void	asy_parse_mode(dev_info_t *devi, struct asycom *asy);
194 static void	asy_soft_state_free(struct asycom *);
195 static char	*asy_hw_name(struct asycom *asy);
196 static void	async_hold_utbrk(void *arg);
197 static void	async_resume_utbrk(struct asyncline *async);
198 static void	async_dtr_free(struct asyncline *async);
199 static int	asy_identify_chip(dev_info_t *devi, struct asycom *asy);
200 static void	asy_reset_fifo(struct asycom *asy, uchar_t flags);
201 static int	asy_getproperty(dev_info_t *devi, struct asycom *asy,
202 		    const char *property);
203 static boolean_t	async_flowcontrol_sw_input(struct asycom *asy,
204 			    async_flowc_action onoff, int type);
205 static void	async_flowcontrol_sw_output(struct asycom *asy,
206 		    async_flowc_action onoff);
207 static void	async_flowcontrol_hw_input(struct asycom *asy,
208 		    async_flowc_action onoff, int type);
209 static void	async_flowcontrol_hw_output(struct asycom *asy,
210 		    async_flowc_action onoff);
211 
212 #define	GET_PROP(devi, pname, pflag, pval, plen) \
213 		(ddi_prop_op(DDI_DEV_T_ANY, (devi), PROP_LEN_AND_VAL_BUF, \
214 		(pflag), (pname), (caddr_t)(pval), (plen)))
215 
216 static ddi_iblock_cookie_t asy_soft_iblock;
217 ddi_softintr_t asy_softintr_id;
218 static	int asy_addedsoft = 0;
219 int	asysoftpend;	/* soft interrupt pending */
220 kmutex_t asy_soft_lock;	/* lock protecting asysoftpend */
221 kmutex_t asy_glob_lock; /* lock protecting global data manipulation */
222 void *asy_soft_state;
223 
224 /* Standard COM port I/O addresses */
225 static const int standard_com_ports[] = {
226 	COM1_IOADDR, COM2_IOADDR, COM3_IOADDR, COM4_IOADDR
227 };
228 
229 static int *com_ports;
230 static uint_t num_com_ports;
231 
232 /*
233  * Baud rate table. Indexed by #defines found in sys/termios.h
234  */
235 ushort_t asyspdtab[] = {
236 	0,	/* 0 baud rate */
237 	0x900,	/* 50 baud rate */
238 	0x600,	/* 75 baud rate */
239 	0x417,	/* 110 baud rate (%0.026) */
240 	0x359,	/* 134 baud rate (%0.058) */
241 	0x300,	/* 150 baud rate */
242 	0x240,	/* 200 baud rate */
243 	0x180,	/* 300 baud rate */
244 	0x0c0,	/* 600 baud rate */
245 	0x060,	/* 1200 baud rate */
246 	0x040,	/* 1800 baud rate */
247 	0x030,	/* 2400 baud rate */
248 	0x018,	/* 4800 baud rate */
249 	0x00c,	/* 9600 baud rate */
250 	0x006,	/* 19200 baud rate */
251 	0x003,	/* 38400 baud rate */
252 
253 	0x002,	/* 57600 baud rate */
254 	0x0,	/* 76800 baud rate not supported */
255 	0x001,	/* 115200 baud rate */
256 	0x0,	/* 153600 baud rate not supported */
257 	0x0,	/* 0x8002 (SMC chip) 230400 baud rate not supported */
258 	0x0,	/* 307200 baud rate not supported */
259 	0x0,	/* 0x8001 (SMC chip) 460800 baud rate not supported */
260 	0x0,	/* unused */
261 	0x0,	/* unused */
262 	0x0,	/* unused */
263 	0x0,	/* unused */
264 	0x0,	/* unused */
265 	0x0,	/* unused */
266 	0x0,	/* unused */
267 	0x0,	/* unused */
268 	0x0,	/* unused */
269 };
270 
271 static int asyrsrv(queue_t *q);
272 static int asyopen(queue_t *rq, dev_t *dev, int flag, int sflag, cred_t *cr);
273 static int asyclose(queue_t *q, int flag, cred_t *credp);
274 static int asywput(queue_t *q, mblk_t *mp);
275 
276 struct module_info asy_info = {
277 	0,
278 	"asy",
279 	0,
280 	INFPSZ,
281 	4096,
282 	128
283 };
284 
285 static struct qinit asy_rint = {
286 	putq,
287 	asyrsrv,
288 	asyopen,
289 	asyclose,
290 	NULL,
291 	&asy_info,
292 	NULL
293 };
294 
295 static struct qinit asy_wint = {
296 	asywput,
297 	NULL,
298 	NULL,
299 	NULL,
300 	NULL,
301 	&asy_info,
302 	NULL
303 };
304 
305 struct streamtab asy_str_info = {
306 	&asy_rint,
307 	&asy_wint,
308 	NULL,
309 	NULL
310 };
311 
312 static int asyinfo(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg,
313 		void **result);
314 static int asyprobe(dev_info_t *);
315 static int asyattach(dev_info_t *, ddi_attach_cmd_t);
316 static int asydetach(dev_info_t *, ddi_detach_cmd_t);
317 
318 static 	struct cb_ops cb_asy_ops = {
319 	nodev,			/* cb_open */
320 	nodev,			/* cb_close */
321 	nodev,			/* cb_strategy */
322 	nodev,			/* cb_print */
323 	nodev,			/* cb_dump */
324 	nodev,			/* cb_read */
325 	nodev,			/* cb_write */
326 	nodev,			/* cb_ioctl */
327 	nodev,			/* cb_devmap */
328 	nodev,			/* cb_mmap */
329 	nodev,			/* cb_segmap */
330 	nochpoll,		/* cb_chpoll */
331 	ddi_prop_op,		/* cb_prop_op */
332 	&asy_str_info,		/* cb_stream */
333 	D_MP			/* cb_flag */
334 };
335 
336 struct dev_ops asy_ops = {
337 	DEVO_REV,		/* devo_rev */
338 	0,			/* devo_refcnt */
339 	asyinfo,		/* devo_getinfo */
340 	nulldev,		/* devo_identify */
341 	asyprobe,		/* devo_probe */
342 	asyattach,		/* devo_attach */
343 	asydetach,		/* devo_detach */
344 	nodev,			/* devo_reset */
345 	&cb_asy_ops,		/* devo_cb_ops */
346 };
347 
348 static struct modldrv modldrv = {
349 	&mod_driverops, /* Type of module.  This one is a driver */
350 	"ASY driver %I%",
351 	&asy_ops,	/* driver ops */
352 };
353 
354 static struct modlinkage modlinkage = {
355 	MODREV_1,
356 	(void *)&modldrv,
357 	NULL
358 };
359 
360 int
361 _init(void)
362 {
363 	int i;
364 
365 	i = ddi_soft_state_init(&asy_soft_state, sizeof (struct asycom), 2);
366 	if (i == 0) {
367 		mutex_init(&asy_glob_lock, NULL, MUTEX_DRIVER, NULL);
368 		if ((i = mod_install(&modlinkage)) != 0) {
369 			mutex_destroy(&asy_glob_lock);
370 			ddi_soft_state_fini(&asy_soft_state);
371 		} else {
372 			DEBUGCONT2(ASY_DEBUG_INIT, "%s, debug = %x\n",
373 			    modldrv.drv_linkinfo, debug);
374 		}
375 	}
376 	return (i);
377 }
378 
379 int
380 _fini(void)
381 {
382 	int i;
383 
384 	if ((i = mod_remove(&modlinkage)) == 0) {
385 		DEBUGCONT1(ASY_DEBUG_INIT, "%s unloading\n",
386 		    modldrv.drv_linkinfo);
387 		ASSERT(max_asy_instance == -1);
388 		mutex_destroy(&asy_glob_lock);
389 		if (asy_addedsoft)
390 			ddi_remove_softintr(asy_softintr_id);
391 		asy_addedsoft = 0;
392 		/* free "motherboard-serial-ports" property if allocated */
393 		if (com_ports != NULL && com_ports != (int *)standard_com_ports)
394 		    ddi_prop_free(com_ports);
395 		com_ports = NULL;
396 		mutex_destroy(&asy_soft_lock);
397 		ddi_soft_state_fini(&asy_soft_state);
398 	}
399 	return (i);
400 }
401 
402 int
403 _info(struct modinfo *modinfop)
404 {
405 	return (mod_info(&modlinkage, modinfop));
406 }
407 
408 static int
409 asydetach(dev_info_t *devi, ddi_detach_cmd_t cmd)
410 {
411 	int instance;
412 	struct asycom *asy;
413 	struct asyncline *async;
414 
415 	if (cmd != DDI_DETACH)
416 		return (DDI_FAILURE);
417 
418 	instance = ddi_get_instance(devi);	/* find out which unit */
419 
420 	asy = ddi_get_soft_state(asy_soft_state, instance);
421 	if (asy == NULL)
422 		return (DDI_FAILURE);
423 	async = asy->asy_priv;
424 
425 	DEBUGNOTE2(ASY_DEBUG_INIT, "asy%d: %s shutdown.",
426 	    instance, asy_hw_name(asy));
427 
428 	/* cancel DTR hold timeout */
429 	if (async->async_dtrtid != 0) {
430 		(void) untimeout(async->async_dtrtid);
431 		async->async_dtrtid = 0;
432 	}
433 
434 	/* remove all minor device node(s) for this device */
435 	ddi_remove_minor_node(devi, NULL);
436 
437 	mutex_destroy(&asy->asy_excl);
438 	mutex_destroy(&asy->asy_excl_hi);
439 	cv_destroy(&async->async_flags_cv);
440 	ddi_remove_intr(devi, 0, asy->asy_iblock);
441 	ddi_regs_map_free(&asy->asy_iohandle);
442 	asy_soft_state_free(asy);
443 	DEBUGNOTE1(ASY_DEBUG_INIT, "asy%d: shutdown complete", instance);
444 	return (DDI_SUCCESS);
445 }
446 
447 /*
448  * asyprobe
449  * We don't bother probing for the hardware, as since Solaris 2.6, device
450  * nodes are only created for auto-detected hardware or nodes explicitly
451  * created by the user, e.g. via the DCA. However, we should check the
452  * device node is at least vaguely usable, i.e. we have a block of 8 i/o
453  * ports. This prevents attempting to attach to bogus serial ports which
454  * some BIOSs still partially report when they are disabled in the BIOS.
455  */
456 static int
457 asyprobe(dev_info_t *devi)
458 {
459 	int instance;
460 	int ret = DDI_PROBE_FAILURE;
461 	int regnum;
462 	int reglen, nregs;
463 	struct reglist {
464 		uint_t bustype;
465 		int base;
466 		int size;
467 	} *reglist = NULL;
468 
469 	instance = ddi_get_instance(devi);
470 
471 	/* Retrieve "reg" property */
472 
473 	if (ddi_getlongprop(DDI_DEV_T_ANY, devi, DDI_PROP_DONTPASS,
474 	    "reg", (caddr_t)&reglist, &reglen) != DDI_PROP_SUCCESS) {
475 		cmn_err(CE_WARN, "asyprobe: \"reg\" property not found "
476 		    "in devices property list");
477 		goto probedone;
478 	}
479 
480 	/* find I/O bus register property */
481 
482 	nregs = reglen / sizeof (struct reglist);
483 	for (regnum = 0; regnum < nregs; regnum++) {
484 		if (reglist[regnum].bustype == 1)
485 			break;
486 	}
487 	if (regnum >= nregs) {
488 		DEBUGCONT1(ASY_DEBUG_INIT,
489 		    "asy%dprobe: No I/O register property", instance);
490 		goto probedone;
491 	}
492 
493 	if (reglist[regnum].size < 8) {	/* not enough registers for a UART */
494 		DEBUGCONT1(ASY_DEBUG_INIT,
495 		    "asy%dprobe: Invalid I/O register property", instance);
496 		goto probedone;
497 	}
498 
499 	ret = DDI_PROBE_DONTCARE;	/* OK, looks like it might be usable */
500 
501 probedone:
502 	if (reglist != NULL)
503 		kmem_free(reglist, reglen);
504 
505 	DEBUGCONT2(ASY_DEBUG_INIT, "asy%dprobe: ret=%s\n", instance,
506 	    ret == DDI_PROBE_DONTCARE ? "DDI_PROBE_DONTCARE" :
507 	    "DDI_PROBE_FAILURE");
508 
509 	return (ret);
510 }
511 
512 static int
513 asyattach(dev_info_t *devi, ddi_attach_cmd_t cmd)
514 {
515 	int instance;
516 	int mcr;
517 	int ret;
518 	int regnum = 0;
519 	int i;
520 	struct asycom *asy;
521 	char name[40];
522 	int status;
523 	static ddi_device_acc_attr_t ioattr = {
524 		DDI_DEVICE_ATTR_V0,
525 		DDI_NEVERSWAP_ACC,
526 		DDI_STRICTORDER_ACC,
527 	};
528 
529 	if (cmd != DDI_ATTACH)
530 		return (DDI_FAILURE);
531 
532 	instance = ddi_get_instance(devi);	/* find out which unit */
533 	ret = ddi_soft_state_zalloc(asy_soft_state, instance);
534 	if (ret != DDI_SUCCESS)
535 		return (DDI_FAILURE);
536 	asy = ddi_get_soft_state(asy_soft_state, instance);
537 	ASSERT(asy != NULL);	/* can't fail - we only just allocated it */
538 	asy->asy_unit = instance;
539 	mutex_enter(&asy_glob_lock);
540 	if (instance > max_asy_instance)
541 		max_asy_instance = instance;
542 	mutex_exit(&asy_glob_lock);
543 
544 	/*CSTYLED*/
545 	{
546 		int reglen, nregs;
547 		int i;
548 		struct {
549 			uint_t bustype;
550 			int base;
551 			int size;
552 		} *reglist;
553 
554 		/* new probe */
555 		if (ddi_getlongprop(DDI_DEV_T_ANY, devi, DDI_PROP_DONTPASS,
556 		    "reg", (caddr_t)&reglist, &reglen) != DDI_PROP_SUCCESS) {
557 			cmn_err(CE_WARN, "asyattach: reg property not found "
558 				"in devices property list");
559 			asy_soft_state_free(asy);
560 			return (DDI_PROBE_FAILURE);
561 		}
562 		regnum = -1;
563 		nregs = reglen / sizeof (*reglist);
564 		for (i = 0; i < nregs; i++) {
565 			switch (reglist[i].bustype) {
566 			case 1:			/* I/O bus reg property */
567 				if (regnum == -1) /* only use the first one */
568 					regnum = i;
569 				break;
570 
571 			case pnpMTS0219:	/* Multitech MT5634ZTX modem */
572 				/* Venus chipset can't do loopback test */
573 				asy->asy_flags2 |= ASY2_NO_LOOPBACK;
574 				break;
575 
576 			default:
577 				break;
578 			}
579 		}
580 		kmem_free(reglist, reglen);
581 	}
582 
583 	if (regnum < 0 ||
584 	    ddi_regs_map_setup(devi, regnum, (caddr_t *)&asy->asy_ioaddr,
585 	    (offset_t)0, (offset_t)0, &ioattr, &asy->asy_iohandle)
586 	    != DDI_SUCCESS) {
587 		cmn_err(CE_WARN, "asy%d: could not map UART registers @ %p",
588 		    instance, (void *)asy->asy_ioaddr);
589 
590 		asy_soft_state_free(asy);
591 		return (DDI_FAILURE);
592 	}
593 
594 	DEBUGCONT2(ASY_DEBUG_INIT, "asy%dattach: UART @ %p\n",
595 	    instance, (void *)asy->asy_ioaddr);
596 
597 	mutex_enter(&asy_glob_lock);
598 	if (com_ports == NULL) {	/* need to initialize com_ports */
599 		if (ddi_prop_lookup_int_array(DDI_DEV_T_ANY, devi, 0,
600 		    "motherboard-serial-ports", &com_ports, &num_com_ports) !=
601 		    DDI_PROP_SUCCESS) {
602 			/* Use our built-in COM[1234] values */
603 			com_ports = (int *)standard_com_ports;
604 			num_com_ports = sizeof (standard_com_ports) /
605 			    sizeof (standard_com_ports[0]);
606 		}
607 		if (num_com_ports > 10) {
608 			/* We run out of single digits for device properties */
609 			num_com_ports = 10;
610 			cmn_err(CE_WARN,
611 			    "More than %d motherboard-serial-ports",
612 			    num_com_ports);
613 		}
614 	}
615 	mutex_exit(&asy_glob_lock);
616 
617 	/*
618 	 * Lookup the i/o address to see if this is a standard COM port
619 	 * in which case we assign it the correct tty[a-d] to match the
620 	 * COM port number, or some other i/o address in which case it
621 	 * will be assigned /dev/term/[0123...] in some rather arbitrary
622 	 * fashion.
623 	 */
624 
625 	for (i = 0; i < num_com_ports; i++) {
626 		if (asy->asy_ioaddr == (uint8_t *)(uintptr_t)com_ports[i]) {
627 			asy->asy_com_port = i + 1;
628 			break;
629 		}
630 	}
631 
632 	/*
633 	 * It appears that there was async hardware that on reset
634 	 * did not clear ICR.  Hence when we get to
635 	 * ddi_get_iblock_cookie below, this hardware would cause
636 	 * the system to hang if there was input available.
637 	 */
638 
639 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0x00);
640 
641 	/* establish default usage */
642 	asy->asy_mcr |= RTS|DTR;		/* do use RTS/DTR after open */
643 	asy->asy_lcr = STOP1|BITS8;		/* default to 1 stop 8 bits */
644 	asy->asy_bidx = B9600;			/* default to 9600  */
645 #ifdef DEBUG
646 	asy->asy_msint_cnt = 0;			/* # of times in async_msint */
647 #endif
648 	mcr = 0;				/* don't enable until open */
649 
650 	if (asy->asy_com_port != 0) {
651 		/*
652 		 * For motherboard ports, emulate tty eeprom properties.
653 		 * Actually, we can't tell if a port is motherboard or not,
654 		 * so for "motherboard ports", read standard DOS COM ports.
655 		 */
656 		switch (asy_getproperty(devi, asy, "ignore-cd")) {
657 		case 0:				/* *-ignore-cd=False */
658 			DEBUGCONT1(ASY_DEBUG_MODEM,
659 			    "asy%dattach: clear ASY_IGNORE_CD\n", instance);
660 			asy->asy_flags &= ~ASY_IGNORE_CD; /* wait for cd */
661 			break;
662 		case 1:				/* *-ignore-cd=True */
663 			/*FALLTHRU*/
664 		default:			/* *-ignore-cd not defined */
665 			/*
666 			 * We set rather silly defaults of soft carrier on
667 			 * and DTR/RTS raised here because it might be that
668 			 * one of the motherboard ports is the system console.
669 			 */
670 			DEBUGCONT1(ASY_DEBUG_MODEM,
671 			    "asy%dattach: set ASY_IGNORE_CD, set RTS & DTR\n",
672 			    instance);
673 			mcr = asy->asy_mcr;		/* rts/dtr on */
674 			asy->asy_flags |= ASY_IGNORE_CD;	/* ignore cd */
675 			break;
676 		}
677 
678 		/* Property for not raising DTR/RTS */
679 		switch (asy_getproperty(devi, asy, "rts-dtr-off")) {
680 		case 0:				/* *-rts-dtr-off=False */
681 			asy->asy_flags |= ASY_RTS_DTR_OFF;	/* OFF */
682 			mcr = asy->asy_mcr;		/* rts/dtr on */
683 			DEBUGCONT1(ASY_DEBUG_MODEM, "asy%dattach: "
684 			    "ASY_RTS_DTR_OFF set and DTR & RTS set\n",
685 			    instance);
686 			break;
687 		case 1:				/* *-rts-dtr-off=True */
688 			/*FALLTHRU*/
689 		default:			/* *-rts-dtr-off undefined */
690 			break;
691 		}
692 
693 		/* Parse property for tty modes */
694 		asy_parse_mode(devi, asy);
695 	} else {
696 		DEBUGCONT1(ASY_DEBUG_MODEM,
697 		    "asy%dattach: clear ASY_IGNORE_CD, clear RTS & DTR\n",
698 		    instance);
699 		asy->asy_flags &= ~ASY_IGNORE_CD;	/* wait for cd */
700 	}
701 
702 	/*
703 	 * Initialize the port with default settings.
704 	 */
705 
706 	asy->asy_fifo_buf = 1;
707 	asy->asy_use_fifo = FIFO_OFF;
708 
709 	/*
710 	 * Get icookie for mutexes initialization
711 	 */
712 	if ((ddi_get_iblock_cookie(devi, 0, &asy->asy_iblock) !=
713 	    DDI_SUCCESS) ||
714 	    (ddi_get_soft_iblock_cookie(devi, DDI_SOFTINT_MED,
715 	    &asy_soft_iblock) != DDI_SUCCESS)) {
716 		ddi_regs_map_free(&asy->asy_iohandle);
717 		cmn_err(CE_CONT,
718 		    "asy%d: could not hook interrupt for UART @ %p\n",
719 		    instance, (void *)asy->asy_ioaddr);
720 		asy_soft_state_free(asy);
721 		return (DDI_FAILURE);
722 	}
723 
724 	/*
725 	 * Initialize mutexes before accessing the hardware
726 	 */
727 	mutex_init(&asy->asy_excl, NULL, MUTEX_DRIVER, asy_soft_iblock);
728 	mutex_init(&asy->asy_excl_hi, NULL, MUTEX_DRIVER,
729 		(void *)asy->asy_iblock);
730 
731 	mutex_enter(&asy->asy_excl);
732 	mutex_enter(&asy->asy_excl_hi);
733 
734 	if (asy_identify_chip(devi, asy) != DDI_SUCCESS) {
735 		mutex_exit(&asy->asy_excl_hi);
736 		mutex_exit(&asy->asy_excl);
737 		mutex_destroy(&asy->asy_excl);
738 		mutex_destroy(&asy->asy_excl_hi);
739 		ddi_regs_map_free(&asy->asy_iohandle);
740 		cmn_err(CE_CONT, "Cannot identify UART chip at %p\n",
741 		    (void *)asy->asy_ioaddr);
742 		asy_soft_state_free(asy);
743 		return (DDI_FAILURE);
744 	}
745 
746 	/* disable all interrupts */
747 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
748 	/* select baud rate generator */
749 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, DLAB);
750 	/* Set the baud rate to 9600 */
751 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + (DAT+DLL),
752 		asyspdtab[asy->asy_bidx] & 0xff);
753 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + (DAT+DLH),
754 		(asyspdtab[asy->asy_bidx] >> 8) & 0xff);
755 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
756 		asy->asy_lcr);
757 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR, mcr);
758 
759 	mutex_exit(&asy->asy_excl_hi);
760 	mutex_exit(&asy->asy_excl);
761 
762 	/*
763 	 * Set up the other components of the asycom structure for this port.
764 	 */
765 	asy->asy_dip = devi;
766 
767 	mutex_enter(&asy_glob_lock);
768 	if (asy_addedsoft == 0) { /* install the soft interrupt handler */
769 		if (ddi_add_softintr(devi, DDI_SOFTINT_MED,
770 		    &asy_softintr_id, NULL, 0, asysoftintr,
771 		    (caddr_t)0) != DDI_SUCCESS) {
772 			mutex_destroy(&asy->asy_excl);
773 			mutex_destroy(&asy->asy_excl_hi);
774 			ddi_regs_map_free(&asy->asy_iohandle);
775 			mutex_exit(&asy_glob_lock);
776 			cmn_err(CE_CONT,
777 				"Can not set soft interrupt for ASY driver\n");
778 			asy_soft_state_free(asy);
779 			return (DDI_FAILURE);
780 		}
781 		mutex_init(&asy_soft_lock, NULL, MUTEX_DRIVER,
782 			(void *)asy->asy_iblock);
783 		asy_addedsoft++;
784 	}
785 	mutex_exit(&asy_glob_lock);
786 
787 	mutex_enter(&asy->asy_excl);
788 	mutex_enter(&asy->asy_excl_hi);
789 
790 	/*
791 	 * Install interrupt handler for this device.
792 	 */
793 	if (ddi_add_intr(devi, 0, NULL, 0, asyintr,
794 	    (caddr_t)asy) != DDI_SUCCESS) {
795 		mutex_exit(&asy->asy_excl_hi);
796 		mutex_exit(&asy->asy_excl);
797 		mutex_destroy(&asy->asy_excl);
798 		mutex_destroy(&asy->asy_excl_hi);
799 		ddi_regs_map_free(&asy->asy_iohandle);
800 		cmn_err(CE_CONT,
801 			"Can not set device interrupt for ASY driver\n");
802 		asy_soft_state_free(asy);
803 		return (DDI_FAILURE);
804 	}
805 
806 	mutex_exit(&asy->asy_excl_hi);
807 	mutex_exit(&asy->asy_excl);
808 
809 	asyinit(asy);	/* initialize the asyncline structure */
810 
811 	/* create minor device nodes for this device */
812 	if (asy->asy_com_port != 0) {
813 		/*
814 		 * For DOS COM ports, add letter suffix so
815 		 * devfsadm can create correct link names.
816 		 */
817 		name[0] = asy->asy_com_port + 'a' - 1;
818 		name[1] = '\0';
819 	} else {
820 		/*
821 		 * ISA port which isn't a standard DOS COM
822 		 * port needs no further qualification.
823 		 */
824 		name[0] = '\0';
825 	}
826 	status = ddi_create_minor_node(devi, name, S_IFCHR, instance,
827 	    asy->asy_com_port != 0 ? DDI_NT_SERIAL_MB : DDI_NT_SERIAL, NULL);
828 	if (status == DDI_SUCCESS) {
829 		(void) strcat(name, ",cu");
830 		status = ddi_create_minor_node(devi, name, S_IFCHR,
831 		    OUTLINE | instance,
832 		    asy->asy_com_port != 0 ? DDI_NT_SERIAL_MB_DO :
833 		    DDI_NT_SERIAL_DO, NULL);
834 	}
835 
836 	if (status != DDI_SUCCESS) {
837 		struct asyncline *async = asy->asy_priv;
838 
839 		ddi_remove_minor_node(devi, NULL);
840 		ddi_remove_intr(devi, 0, asy->asy_iblock);
841 		mutex_destroy(&asy->asy_excl);
842 		mutex_destroy(&asy->asy_excl_hi);
843 		cv_destroy(&async->async_flags_cv);
844 		ddi_regs_map_free(&asy->asy_iohandle);
845 		asy_soft_state_free(asy);
846 		return (DDI_FAILURE);
847 	}
848 
849 	/*
850 	 * Fill in the polled I/O structure.
851 	 */
852 	asy->polledio.cons_polledio_version = CONSPOLLEDIO_V0;
853 	asy->polledio.cons_polledio_argument = (struct cons_polledio_arg *)asy;
854 	asy->polledio.cons_polledio_putchar = asyputchar;
855 	asy->polledio.cons_polledio_getchar = asygetchar;
856 	asy->polledio.cons_polledio_ischar = asyischar;
857 	asy->polledio.cons_polledio_enter = NULL;
858 	asy->polledio.cons_polledio_exit = NULL;
859 
860 	ddi_report_dev(devi);
861 	DEBUGCONT1(ASY_DEBUG_INIT, "asy%dattach: done\n", instance);
862 	return (DDI_SUCCESS);
863 }
864 
865 /*ARGSUSED*/
866 static int
867 asyinfo(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg,
868 	void **result)
869 {
870 	dev_t dev = (dev_t)arg;
871 	int instance, error;
872 	struct asycom *asy;
873 
874 	instance = UNIT(dev);
875 
876 	switch (infocmd) {
877 	case DDI_INFO_DEVT2DEVINFO:
878 		asy = ddi_get_soft_state(asy_soft_state, instance);
879 		if ((asy == NULL) || (asy->asy_dip == NULL))
880 			error = DDI_FAILURE;
881 		else {
882 			*result = (void *) asy->asy_dip;
883 			error = DDI_SUCCESS;
884 		}
885 		break;
886 	case DDI_INFO_DEVT2INSTANCE:
887 		*result = (void *)(intptr_t)instance;
888 		error = DDI_SUCCESS;
889 		break;
890 	default:
891 		error = DDI_FAILURE;
892 	}
893 	return (error);
894 }
895 
896 /* asy_getproperty -- walk through all name variants until we find a match */
897 
898 static int
899 asy_getproperty(dev_info_t *devi, struct asycom *asy, const char *property)
900 {
901 	int len;
902 	int ret;
903 	char letter = asy->asy_com_port + 'a' - 1;	/* for ttya */
904 	char number = asy->asy_com_port + '0';		/* for COM1 */
905 	char val[40];
906 	char name[40];
907 
908 	/* Property for ignoring DCD */
909 	(void) sprintf(name, "tty%c-%s", letter, property);
910 	len = sizeof (val);
911 	ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
912 	if (ret != DDI_PROP_SUCCESS) {
913 		(void) sprintf(name, "com%c-%s", number, property);
914 		len = sizeof (val);
915 		ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val,
916 				&len);
917 	}
918 	if (ret != DDI_PROP_SUCCESS) {
919 		(void) sprintf(name, "tty0%c-%s", number, property);
920 		len = sizeof (val);
921 		ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val,
922 				&len);
923 	}
924 	if (ret != DDI_PROP_SUCCESS) {
925 		(void) sprintf(name, "port-%c-%s", letter, property);
926 		len = sizeof (val);
927 		ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val,
928 				&len);
929 	}
930 	if (ret != DDI_PROP_SUCCESS)
931 		return (-1);		/* property non-existant */
932 	if (val[0] == 'f' || val[0] == 'F' || val[0] == '0')
933 		return (0);		/* property false/0 */
934 	return (1);			/* property true/!0 */
935 }
936 
937 /* asy_soft_state_free - local wrapper for ddi_soft_state_free(9F) */
938 
939 static void
940 asy_soft_state_free(struct asycom *asy)
941 {
942 	mutex_enter(&asy_glob_lock);
943 	/* If we were the max_asy_instance, work out new value */
944 	if (asy->asy_unit == max_asy_instance) {
945 		while (--max_asy_instance >= 0) {
946 			if (ddi_get_soft_state(asy_soft_state,
947 			    max_asy_instance) != NULL)
948 				break;
949 		}
950 	}
951 	mutex_exit(&asy_glob_lock);
952 
953 	if (asy->asy_priv != NULL) {
954 		kmem_free(asy->asy_priv, sizeof (struct asyncline));
955 		asy->asy_priv = NULL;
956 	}
957 	ddi_soft_state_free(asy_soft_state, asy->asy_unit);
958 }
959 
960 static char *
961 asy_hw_name(struct asycom *asy)
962 {
963 	switch (asy->asy_hwtype) {
964 	case ASY8250A:
965 		return ("8250A/16450");
966 	case ASY16550:
967 		return ("16550");
968 	case ASY16550A:
969 		return ("16550A");
970 	case ASY16650:
971 		return ("16650");
972 	case ASY16750:
973 		return ("16750");
974 	default:
975 		DEBUGNOTE2(ASY_DEBUG_INIT,
976 		    "asy%d: asy_hw_name: unknown asy_hwtype: %d",
977 		    asy->asy_unit, asy->asy_hwtype);
978 		return ("?");
979 	}
980 }
981 
982 static int
983 asy_identify_chip(dev_info_t *devi, struct asycom *asy)
984 {
985 	int ret;
986 	int mcr;
987 	dev_t dev;
988 	uint_t hwtype;
989 
990 	if (asy_scr_test) {
991 		/* Check scratch register works. */
992 
993 		/* write to scratch register */
994 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + SCR, SCRTEST);
995 		/* make sure that pattern doesn't just linger on the bus */
996 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + FIFOR, 0x00);
997 		/* read data back from scratch register */
998 		ret = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + SCR);
999 		if (ret != SCRTEST) {
1000 			/*
1001 			 * Scratch register not working.
1002 			 * Probably not an async chip.
1003 			 * 8250 and 8250B don't have scratch registers,
1004 			 * but only worked in ancient PC XT's anyway.
1005 			 */
1006 			cmn_err(CE_CONT, "asy%d: UART @ %p "
1007 			    "scratch register: expected 0x5a, got 0x%02x\n",
1008 			    asy->asy_unit, (void *)asy->asy_ioaddr, ret);
1009 			return (DDI_FAILURE);
1010 		}
1011 	}
1012 	/*
1013 	 * Use 16550 fifo reset sequence specified in NS application
1014 	 * note. Disable fifos until chip is initialized.
1015 	 */
1016 	ddi_put8(asy->asy_iohandle,
1017 	    asy->asy_ioaddr + FIFOR, 0x00);	/* clear */
1018 	ddi_put8(asy->asy_iohandle,
1019 	    asy->asy_ioaddr + FIFOR, FIFO_ON);	/* enable */
1020 	ddi_put8(asy->asy_iohandle,
1021 	    asy->asy_ioaddr + FIFOR, FIFO_ON | FIFORXFLSH);
1022 						/* reset */
1023 	if (asymaxchip >= ASY16650 && asy_scr_test) {
1024 		/*
1025 		 * Reset 16650 enhanced regs also, in case we have one of these
1026 		 */
1027 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1028 		    EFRACCESS);
1029 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + EFR,
1030 		    0);
1031 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1032 		    STOP1|BITS8);
1033 	}
1034 
1035 	/*
1036 	 * See what sort of FIFO we have.
1037 	 * Try enabling it and see what chip makes of this.
1038 	 */
1039 
1040 	asy->asy_fifor = 0;
1041 	asy->asy_hwtype = asymaxchip; /* just for asy_reset_fifo() */
1042 	if (asymaxchip >= ASY16550A)
1043 		asy->asy_fifor |=
1044 		    FIFO_ON | FIFODMA | (asy_trig_level & 0xff);
1045 	if (asymaxchip >= ASY16650)
1046 		asy->asy_fifor |= FIFOEXTRA1 | FIFOEXTRA2;
1047 
1048 	asy_reset_fifo(asy, FIFOTXFLSH | FIFORXFLSH);
1049 
1050 	mcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
1051 	ret = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + ISR);
1052 	DEBUGCONT4(ASY_DEBUG_CHIP,
1053 	    "asy%d: probe fifo FIFOR=0x%02x ISR=0x%02x MCR=0x%02x\n",
1054 	    asy->asy_unit, asy->asy_fifor | FIFOTXFLSH | FIFORXFLSH,
1055 	    ret, mcr);
1056 	switch (ret & 0xf0) {
1057 	case 0x40:
1058 		hwtype = ASY16550; /* 16550 with broken FIFO */
1059 		asy->asy_fifor = 0;
1060 		break;
1061 	case 0xc0:
1062 		hwtype = ASY16550A;
1063 		asy->asy_fifo_buf = 16;
1064 		asy->asy_use_fifo = FIFO_ON;
1065 		asy->asy_fifor &= ~(FIFOEXTRA1 | FIFOEXTRA2);
1066 		break;
1067 	case 0xe0:
1068 		hwtype = ASY16650;
1069 		asy->asy_fifo_buf = 32;
1070 		asy->asy_use_fifo = FIFO_ON;
1071 		asy->asy_fifor &= ~(FIFOEXTRA1);
1072 		break;
1073 	case 0xf0:
1074 		/*
1075 		 * Note we get 0xff if chip didn't return us anything,
1076 		 * e.g. if there's no chip there.
1077 		 */
1078 		if (ret == 0xff) {
1079 			cmn_err(CE_CONT, "asy%d: UART @ %p "
1080 			    "interrupt register: got 0xff\n",
1081 			    asy->asy_unit, (void *)asy->asy_ioaddr);
1082 			return (DDI_FAILURE);
1083 		}
1084 		/*FALLTHRU*/
1085 	case 0xd0:
1086 		hwtype = ASY16750;
1087 		asy->asy_fifo_buf = 64;
1088 		asy->asy_use_fifo = FIFO_ON;
1089 		break;
1090 	default:
1091 		hwtype = ASY8250A; /* No FIFO */
1092 		asy->asy_fifor = 0;
1093 	}
1094 
1095 	if (hwtype > asymaxchip) {
1096 		cmn_err(CE_CONT, "asy%d: UART @ %p "
1097 		    "unexpected probe result: "
1098 		    "FIFOR=0x%02x ISR=0x%02x MCR=0x%02x\n",
1099 		    asy->asy_unit, (void *)asy->asy_ioaddr,
1100 		    asy->asy_fifor | FIFOTXFLSH | FIFORXFLSH, ret, mcr);
1101 		return (DDI_FAILURE);
1102 	}
1103 
1104 	/*
1105 	 * Now reset the FIFO operation appropriate for the chip type.
1106 	 * Note we must call asy_reset_fifo() before any possible
1107 	 * downgrade of the asy->asy_hwtype, or it may not disable
1108 	 * the more advanced features we specifically want downgraded.
1109 	 */
1110 	asy_reset_fifo(asy, 0);
1111 	asy->asy_hwtype = hwtype;
1112 
1113 	/*
1114 	 * Check for Exar/Startech ST16C650, which will still look like a
1115 	 * 16550A until we enable its enhanced mode.
1116 	 */
1117 	if (asy->asy_hwtype == ASY16550A && asymaxchip >= ASY16650 &&
1118 	    asy_scr_test) {
1119 		/* Enable enhanced mode register access */
1120 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1121 		    EFRACCESS);
1122 		/* zero scratch register (not scratch register if enhanced) */
1123 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + SCR, 0);
1124 		/* Disable enhanced mode register access */
1125 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1126 		    STOP1|BITS8);
1127 		/* read back scratch register */
1128 		ret = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + SCR);
1129 		if (ret == SCRTEST) {
1130 			/* looks like we have an ST16650 -- enable it */
1131 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1132 			    EFRACCESS);
1133 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + EFR,
1134 			    ENHENABLE);
1135 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1136 			    STOP1|BITS8);
1137 			asy->asy_hwtype = ASY16650;
1138 			asy->asy_fifo_buf = 32;
1139 			asy->asy_fifor |= 0x10; /* 24 byte txfifo trigger */
1140 			asy_reset_fifo(asy, 0);
1141 		}
1142 	}
1143 
1144 	/*
1145 	 * If we think we might have a FIFO larger than 16 characters,
1146 	 * measure FIFO size and check it against expected.
1147 	 */
1148 	if (asy_fifo_test > 0 &&
1149 	    !(asy->asy_flags2 & ASY2_NO_LOOPBACK) &&
1150 	    (asy->asy_fifo_buf > 16 ||
1151 	    (asy_fifo_test > 1 && asy->asy_use_fifo == FIFO_ON) ||
1152 	    ASY_DEBUG(ASY_DEBUG_CHIP))) {
1153 		int i;
1154 
1155 		/* Set baud rate to 57600 (fairly arbitrary choice) */
1156 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1157 		    DLAB);
1158 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
1159 		    asyspdtab[B57600] & 0xff);
1160 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR,
1161 		    (asyspdtab[B57600] >> 8) & 0xff);
1162 		/* Set 8 bits, 1 stop bit */
1163 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1164 		    STOP1|BITS8);
1165 		/* Set loopback mode */
1166 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1167 		    DTR | RTS | ASY_LOOP | OUT1 | OUT2);
1168 
1169 		/* Overfill fifo */
1170 		for (i = 0; i < asy->asy_fifo_buf * 2; i++) {
1171 			ddi_put8(asy->asy_iohandle,
1172 			    asy->asy_ioaddr + DAT, i);
1173 		}
1174 		/*
1175 		 * Now there's an interesting question here about which
1176 		 * FIFO we're testing the size of, RX or TX. We just
1177 		 * filled the TX FIFO much faster than it can empty,
1178 		 * although it is possible one or two characters may
1179 		 * have gone from it to the TX shift register.
1180 		 * We wait for enough time for all the characters to
1181 		 * move into the RX FIFO and any excess characters to
1182 		 * have been lost, and then read all the RX FIFO. So
1183 		 * the answer we finally get will be the size which is
1184 		 * the MIN(RX FIFO,(TX FIFO + 1 or 2)). The critical
1185 		 * one is actually the TX FIFO, because if we overfill
1186 		 * it in normal operation, the excess characters are
1187 		 * lost with no warning.
1188 		 */
1189 		/*
1190 		 * Wait for characters to move into RX FIFO.
1191 		 * In theory, 200 * asy->asy_fifo_buf * 2 should be
1192 		 * enough. However, in practice it isn't always, so we
1193 		 * increase to 400 so some slow 16550A's finish, and we
1194 		 * increase to 3 so we spot more characters coming back
1195 		 * than we sent, in case that should ever happen.
1196 		 */
1197 		delay(drv_usectohz(400 * asy->asy_fifo_buf * 3));
1198 
1199 		/* Now see how many characters we can read back */
1200 		for (i = 0; i < asy->asy_fifo_buf * 3; i++) {
1201 			ret = ddi_get8(asy->asy_iohandle,
1202 			    asy->asy_ioaddr + LSR);
1203 			if (!(ret & RCA))
1204 				break;	/* FIFO emptied */
1205 			(void) ddi_get8(asy->asy_iohandle,
1206 			    asy->asy_ioaddr + DAT); /* lose another */
1207 		}
1208 
1209 		DEBUGCONT3(ASY_DEBUG_CHIP,
1210 		    "asy%d FIFO size: expected=%d, measured=%d\n",
1211 		    asy->asy_unit, asy->asy_fifo_buf, i);
1212 
1213 		hwtype = asy->asy_hwtype;
1214 		if (i < asy->asy_fifo_buf) {
1215 			/*
1216 			 * FIFO is somewhat smaller than we anticipated.
1217 			 * If we have 16 characters usable, then this
1218 			 * UART will probably work well enough in
1219 			 * 16550A mode. If less than 16 characters,
1220 			 * then we'd better not use it at all.
1221 			 * UARTs with busted FIFOs do crop up.
1222 			 */
1223 			if (i >= 16 && asy->asy_fifo_buf >= 16) {
1224 				/* fall back to a 16550A */
1225 				hwtype = ASY16550A;
1226 				asy->asy_fifo_buf = 16;
1227 				asy->asy_fifor &= ~(FIFOEXTRA1 | FIFOEXTRA2);
1228 			} else {
1229 				/* fall back to no FIFO at all */
1230 				hwtype = ASY16550;
1231 				asy->asy_fifo_buf = 1;
1232 				asy->asy_use_fifo = FIFO_OFF;
1233 				asy->asy_fifor &=
1234 				    ~(FIFO_ON | FIFOEXTRA1 | FIFOEXTRA2);
1235 			}
1236 		}
1237 		/*
1238 		 * We will need to reprogram the FIFO if we changed
1239 		 * our mind about how to drive it above, and in any
1240 		 * case, it would be a good idea to flush any garbage
1241 		 * out incase the loopback test left anything behind.
1242 		 * Again as earlier above, we must call asy_reset_fifo()
1243 		 * before any possible downgrade of asy->asy_hwtype.
1244 		 */
1245 		if (asy->asy_hwtype >= ASY16650 && hwtype < ASY16650) {
1246 			/* Disable 16650 enhanced mode */
1247 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1248 			    EFRACCESS);
1249 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + EFR,
1250 			    0);
1251 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1252 			    STOP1|BITS8);
1253 		}
1254 		asy_reset_fifo(asy, FIFOTXFLSH | FIFORXFLSH);
1255 		asy->asy_hwtype = hwtype;
1256 
1257 		/* Clear loopback mode and restore DTR/RTS */
1258 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR, mcr);
1259 	}
1260 
1261 	DEBUGNOTE3(ASY_DEBUG_CHIP, "asy%d %s @ %p",
1262 	    asy->asy_unit, asy_hw_name(asy), (void *)asy->asy_ioaddr);
1263 
1264 	/* Make UART type visible in device tree for prtconf, etc */
1265 	dev = makedevice(DDI_MAJOR_T_UNKNOWN, asy->asy_unit);
1266 	(void) ddi_prop_update_string(dev, devi, "uart", asy_hw_name(asy));
1267 
1268 	if (asy->asy_hwtype == ASY16550)	/* for broken 16550's, */
1269 		asy->asy_hwtype = ASY8250A;	/* drive them as 8250A */
1270 
1271 	return (DDI_SUCCESS);
1272 }
1273 
1274 /*
1275  * asyinit() initializes the TTY protocol-private data for this channel
1276  * before enabling the interrupts.
1277  */
1278 static void
1279 asyinit(struct asycom *asy)
1280 {
1281 	struct asyncline *async;
1282 
1283 	asy->asy_priv = kmem_zalloc(sizeof (struct asyncline), KM_SLEEP);
1284 	async = asy->asy_priv;
1285 	mutex_enter(&asy->asy_excl);
1286 	async->async_common = asy;
1287 	cv_init(&async->async_flags_cv, NULL, CV_DRIVER, NULL);
1288 	mutex_exit(&asy->asy_excl);
1289 }
1290 
1291 /*ARGSUSED3*/
1292 static int
1293 asyopen(queue_t *rq, dev_t *dev, int flag, int sflag, cred_t *cr)
1294 {
1295 	struct asycom	*asy;
1296 	struct asyncline *async;
1297 	int		mcr;
1298 	int		unit;
1299 	int 		len;
1300 	struct termios 	*termiosp;
1301 
1302 	unit = UNIT(*dev);
1303 	DEBUGCONT1(ASY_DEBUG_CLOSE, "asy%dopen\n", unit);
1304 	asy = ddi_get_soft_state(asy_soft_state, unit);
1305 	if (asy == NULL)
1306 		return (ENXIO);		/* unit not configured */
1307 	async = asy->asy_priv;
1308 	mutex_enter(&asy->asy_excl);
1309 
1310 again:
1311 	mutex_enter(&asy->asy_excl_hi);
1312 
1313 	/*
1314 	 * Block waiting for carrier to come up, unless this is a no-delay open.
1315 	 */
1316 	if (!(async->async_flags & ASYNC_ISOPEN)) {
1317 		/*
1318 		 * Set the default termios settings (cflag).
1319 		 * Others are set in ldterm.
1320 		 */
1321 		mutex_exit(&asy->asy_excl_hi);
1322 
1323 		if (ddi_getlongprop(DDI_DEV_T_ANY, ddi_root_node(),
1324 		    0, "ttymodes",
1325 		    (caddr_t)&termiosp, &len) == DDI_PROP_SUCCESS &&
1326 		    len == sizeof (struct termios)) {
1327 			async->async_ttycommon.t_cflag = termiosp->c_cflag;
1328 			kmem_free(termiosp, len);
1329 		} else
1330 			cmn_err(CE_WARN,
1331 				"asy: couldn't get ttymodes property!");
1332 		mutex_enter(&asy->asy_excl_hi);
1333 
1334 		/* eeprom mode support - respect properties */
1335 		if (asy->asy_cflag)
1336 			async->async_ttycommon.t_cflag = asy->asy_cflag;
1337 
1338 		async->async_ttycommon.t_iflag = 0;
1339 		async->async_ttycommon.t_iocpending = NULL;
1340 		async->async_ttycommon.t_size.ws_row = 0;
1341 		async->async_ttycommon.t_size.ws_col = 0;
1342 		async->async_ttycommon.t_size.ws_xpixel = 0;
1343 		async->async_ttycommon.t_size.ws_ypixel = 0;
1344 		async->async_dev = *dev;
1345 		async->async_wbufcid = 0;
1346 
1347 		async->async_startc = CSTART;
1348 		async->async_stopc = CSTOP;
1349 		asy_program(asy, ASY_INIT);
1350 	} else if ((async->async_ttycommon.t_flags & TS_XCLUDE) &&
1351 						secpolicy_excl_open(cr) != 0) {
1352 		mutex_exit(&asy->asy_excl_hi);
1353 		mutex_exit(&asy->asy_excl);
1354 		return (EBUSY);
1355 	} else if ((*dev & OUTLINE) && !(async->async_flags & ASYNC_OUT)) {
1356 		mutex_exit(&asy->asy_excl_hi);
1357 		mutex_exit(&asy->asy_excl);
1358 		return (EBUSY);
1359 	}
1360 
1361 	if (*dev & OUTLINE)
1362 		async->async_flags |= ASYNC_OUT;
1363 
1364 	/* Raise DTR on every open, but delay if it was just lowered. */
1365 	while (async->async_flags & ASYNC_DTR_DELAY) {
1366 		DEBUGCONT1(ASY_DEBUG_MODEM,
1367 		    "asy%dopen: waiting for the ASYNC_DTR_DELAY to be clear\n",
1368 		    unit);
1369 		mutex_exit(&asy->asy_excl_hi);
1370 		if (cv_wait_sig(&async->async_flags_cv,
1371 		    &asy->asy_excl) == 0) {
1372 			DEBUGCONT1(ASY_DEBUG_MODEM,
1373 			    "asy%dopen: interrupted by signal, exiting\n",
1374 			    unit);
1375 			mutex_exit(&asy->asy_excl);
1376 			return (EINTR);
1377 		}
1378 		mutex_enter(&asy->asy_excl_hi);
1379 	}
1380 
1381 	mcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
1382 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1383 		mcr|(asy->asy_mcr&DTR));
1384 
1385 	DEBUGCONT3(ASY_DEBUG_INIT,
1386 		"asy%dopen: \"Raise DTR on every open\": make mcr = %x, "
1387 		"make TS_SOFTCAR = %s\n",
1388 		unit, mcr|(asy->asy_mcr&DTR),
1389 		(asy->asy_flags & ASY_IGNORE_CD) ? "ON" : "OFF");
1390 	if (asy->asy_flags & ASY_IGNORE_CD) {
1391 		DEBUGCONT1(ASY_DEBUG_MODEM,
1392 			"asy%dopen: ASY_IGNORE_CD set, set TS_SOFTCAR\n",
1393 			unit);
1394 		async->async_ttycommon.t_flags |= TS_SOFTCAR;
1395 	}
1396 	else
1397 		async->async_ttycommon.t_flags &= ~TS_SOFTCAR;
1398 
1399 	/*
1400 	 * Check carrier.
1401 	 */
1402 	asy->asy_msr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MSR);
1403 	DEBUGCONT3(ASY_DEBUG_INIT, "asy%dopen: TS_SOFTCAR is %s, "
1404 		"MSR & DCD is %s\n",
1405 		unit,
1406 		(async->async_ttycommon.t_flags & TS_SOFTCAR) ? "set" : "clear",
1407 		(asy->asy_msr & DCD) ? "set" : "clear");
1408 	if (asy->asy_msr & DCD)
1409 		async->async_flags |= ASYNC_CARR_ON;
1410 	else
1411 		async->async_flags &= ~ASYNC_CARR_ON;
1412 	mutex_exit(&asy->asy_excl_hi);
1413 
1414 	/*
1415 	 * If FNDELAY and FNONBLOCK are clear, block until carrier up.
1416 	 * Quit on interrupt.
1417 	 */
1418 	if (!(flag & (FNDELAY|FNONBLOCK)) &&
1419 	    !(async->async_ttycommon.t_cflag & CLOCAL)) {
1420 		if ((!(async->async_flags & (ASYNC_CARR_ON|ASYNC_OUT)) &&
1421 		    !(async->async_ttycommon.t_flags & TS_SOFTCAR)) ||
1422 		    ((async->async_flags & ASYNC_OUT) &&
1423 		    !(*dev & OUTLINE))) {
1424 			async->async_flags |= ASYNC_WOPEN;
1425 			if (cv_wait_sig(&async->async_flags_cv,
1426 			    &asy->asy_excl) == B_FALSE) {
1427 				async->async_flags &= ~ASYNC_WOPEN;
1428 				mutex_exit(&asy->asy_excl);
1429 				return (EINTR);
1430 			}
1431 			async->async_flags &= ~ASYNC_WOPEN;
1432 			goto again;
1433 		}
1434 	} else if ((async->async_flags & ASYNC_OUT) && !(*dev & OUTLINE)) {
1435 		mutex_exit(&asy->asy_excl);
1436 		return (EBUSY);
1437 	}
1438 
1439 	async->async_ttycommon.t_readq = rq;
1440 	async->async_ttycommon.t_writeq = WR(rq);
1441 	rq->q_ptr = WR(rq)->q_ptr = (caddr_t)async;
1442 	mutex_exit(&asy->asy_excl);
1443 	/*
1444 	 * Caution here -- qprocson sets the pointers that are used by canput
1445 	 * called by async_softint.  ASYNC_ISOPEN must *not* be set until those
1446 	 * pointers are valid.
1447 	 */
1448 	qprocson(rq);
1449 	async->async_flags |= ASYNC_ISOPEN;
1450 	async->async_polltid = 0;
1451 	DEBUGCONT1(ASY_DEBUG_INIT, "asy%dopen: done\n", unit);
1452 	return (0);
1453 }
1454 
1455 static void
1456 async_progress_check(void *arg)
1457 {
1458 	struct asyncline *async = arg;
1459 	struct asycom	 *asy = async->async_common;
1460 	mblk_t *bp;
1461 
1462 	/*
1463 	 * We define "progress" as either waiting on a timed break or delay, or
1464 	 * having had at least one transmitter interrupt.  If none of these are
1465 	 * true, then just terminate the output and wake up that close thread.
1466 	 */
1467 	mutex_enter(&asy->asy_excl);
1468 	mutex_enter(&asy->asy_excl_hi);
1469 	if (!(async->async_flags & (ASYNC_BREAK|ASYNC_DELAY|ASYNC_PROGRESS))) {
1470 		async->async_ocnt = 0;
1471 		async->async_flags &= ~ASYNC_BUSY;
1472 		async->async_timer = 0;
1473 		bp = async->async_xmitblk;
1474 		async->async_xmitblk = NULL;
1475 		mutex_exit(&asy->asy_excl_hi);
1476 		if (bp != NULL)
1477 			freeb(bp);
1478 		/*
1479 		 * Since this timer is running, we know that we're in exit(2).
1480 		 * That means that the user can't possibly be waiting on any
1481 		 * valid ioctl(2) completion anymore, and we should just flush
1482 		 * everything.
1483 		 */
1484 		flushq(async->async_ttycommon.t_writeq, FLUSHALL);
1485 		cv_broadcast(&async->async_flags_cv);
1486 	} else {
1487 		async->async_flags &= ~ASYNC_PROGRESS;
1488 		async->async_timer = timeout(async_progress_check, async,
1489 		    drv_usectohz(asy_drain_check));
1490 		mutex_exit(&asy->asy_excl_hi);
1491 	}
1492 	mutex_exit(&asy->asy_excl);
1493 }
1494 
1495 /*
1496  * Release DTR so that asyopen() can raise it.
1497  */
1498 static void
1499 async_dtr_free(struct asyncline *async)
1500 {
1501 	struct asycom *asy = async->async_common;
1502 
1503 	DEBUGCONT0(ASY_DEBUG_MODEM,
1504 	    "async_dtr_free, clearing ASYNC_DTR_DELAY\n");
1505 	mutex_enter(&asy->asy_excl);
1506 	async->async_flags &= ~ASYNC_DTR_DELAY;
1507 	async->async_dtrtid = 0;
1508 	cv_broadcast(&async->async_flags_cv);
1509 	mutex_exit(&asy->asy_excl);
1510 }
1511 
1512 /*
1513  * Close routine.
1514  */
1515 /*ARGSUSED2*/
1516 static int
1517 asyclose(queue_t *q, int flag, cred_t *credp)
1518 {
1519 	struct asyncline *async;
1520 	struct asycom	 *asy;
1521 	int icr, lcr;
1522 #ifdef DEBUG
1523 	int instance;
1524 #endif
1525 
1526 	async = (struct asyncline *)q->q_ptr;
1527 	ASSERT(async != NULL);
1528 #ifdef DEBUG
1529 	instance = UNIT(async->async_dev);
1530 	DEBUGCONT1(ASY_DEBUG_CLOSE, "asy%dclose\n", instance);
1531 #endif
1532 	asy = async->async_common;
1533 
1534 	mutex_enter(&asy->asy_excl);
1535 	async->async_flags |= ASYNC_CLOSING;
1536 
1537 	/*
1538 	 * Turn off PPS handling early to avoid events occuring during
1539 	 * close.  Also reset the DCD edge monitoring bit.
1540 	 */
1541 	mutex_enter(&asy->asy_excl_hi);
1542 	asy->asy_flags &= ~(ASY_PPS | ASY_PPS_EDGE);
1543 	mutex_exit(&asy->asy_excl_hi);
1544 
1545 	/*
1546 	 * There are two flavors of break -- timed (M_BREAK or TCSBRK) and
1547 	 * untimed (TIOCSBRK).  For the timed case, these are enqueued on our
1548 	 * write queue and there's a timer running, so we don't have to worry
1549 	 * about them.  For the untimed case, though, the user obviously made a
1550 	 * mistake, because these are handled immediately.  We'll terminate the
1551 	 * break now and honor his implicit request by discarding the rest of
1552 	 * the data.
1553 	 */
1554 	if (async->async_flags & ASYNC_OUT_SUSPEND) {
1555 		if (async->async_utbrktid != 0) {
1556 			(void) untimeout(async->async_utbrktid);
1557 			async->async_utbrktid = 0;
1558 		}
1559 		mutex_enter(&asy->asy_excl_hi);
1560 		lcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
1561 		ddi_put8(asy->asy_iohandle,
1562 		    asy->asy_ioaddr + LCR, (lcr & ~SETBREAK));
1563 		mutex_exit(&asy->asy_excl_hi);
1564 		async->async_flags &= ~ASYNC_OUT_SUSPEND;
1565 		goto nodrain;
1566 	}
1567 
1568 	/*
1569 	 * If the user told us not to delay the close ("non-blocking"), then
1570 	 * don't bother trying to drain.
1571 	 *
1572 	 * If the user did M_STOP (ASYNC_STOPPED), there's no hope of ever
1573 	 * getting an M_START (since these messages aren't enqueued), and the
1574 	 * only other way to clear the stop condition is by loss of DCD, which
1575 	 * would discard the queue data.  Thus, we drop the output data if
1576 	 * ASYNC_STOPPED is set.
1577 	 */
1578 	if ((flag & (FNDELAY|FNONBLOCK)) ||
1579 	    (async->async_flags & ASYNC_STOPPED)) {
1580 		goto nodrain;
1581 	}
1582 
1583 	/*
1584 	 * If there's any pending output, then we have to try to drain it.
1585 	 * There are two main cases to be handled:
1586 	 *	- called by close(2): need to drain until done or until
1587 	 *	  a signal is received.  No timeout.
1588 	 *	- called by exit(2): need to drain while making progress
1589 	 *	  or until a timeout occurs.  No signals.
1590 	 *
1591 	 * If we can't rely on receiving a signal to get us out of a hung
1592 	 * session, then we have to use a timer.  In this case, we set a timer
1593 	 * to check for progress in sending the output data -- all that we ask
1594 	 * (at each interval) is that there's been some progress made.  Since
1595 	 * the interrupt routine grabs buffers from the write queue, we can't
1596 	 * trust changes in async_ocnt.  Instead, we use a progress flag.
1597 	 *
1598 	 * Note that loss of carrier will cause the output queue to be flushed,
1599 	 * and we'll wake up again and finish normally.
1600 	 */
1601 	if (!ddi_can_receive_sig() && asy_drain_check != 0) {
1602 		async->async_flags &= ~ASYNC_PROGRESS;
1603 		async->async_timer = timeout(async_progress_check, async,
1604 		    drv_usectohz(asy_drain_check));
1605 	}
1606 	while (async->async_ocnt > 0 ||
1607 	    async->async_ttycommon.t_writeq->q_first != NULL ||
1608 	    (async->async_flags & (ASYNC_BUSY|ASYNC_BREAK|ASYNC_DELAY))) {
1609 		if (cv_wait_sig(&async->async_flags_cv, &asy->asy_excl) == 0)
1610 			break;
1611 	}
1612 	if (async->async_timer != 0) {
1613 		(void) untimeout(async->async_timer);
1614 		async->async_timer = 0;
1615 	}
1616 
1617 nodrain:
1618 	async->async_ocnt = 0;
1619 	if (async->async_xmitblk != NULL)
1620 		freeb(async->async_xmitblk);
1621 	async->async_xmitblk = NULL;
1622 
1623 	/*
1624 	 * If line has HUPCL set or is incompletely opened fix up the modem
1625 	 * lines.
1626 	 */
1627 	DEBUGCONT1(ASY_DEBUG_MODEM,
1628 		"asy%dclose: next check HUPCL flag\n", instance);
1629 	mutex_enter(&asy->asy_excl_hi);
1630 	if ((async->async_ttycommon.t_cflag & HUPCL) ||
1631 	    (async->async_flags & ASYNC_WOPEN)) {
1632 		DEBUGCONT3(ASY_DEBUG_MODEM,
1633 			"asy%dclose: HUPCL flag = %x, ASYNC_WOPEN flag = %x\n",
1634 			instance,
1635 			async->async_ttycommon.t_cflag & HUPCL,
1636 			async->async_ttycommon.t_cflag & ASYNC_WOPEN);
1637 		async->async_flags |= ASYNC_DTR_DELAY;
1638 
1639 		/* turn off DTR, RTS but NOT interrupt to 386 */
1640 		if (asy->asy_flags & (ASY_IGNORE_CD|ASY_RTS_DTR_OFF)) {
1641 			DEBUGCONT3(ASY_DEBUG_MODEM,
1642 				"asy%dclose: ASY_IGNORE_CD flag = %x, "
1643 				"ASY_RTS_DTR_OFF flag = %x\n",
1644 				instance,
1645 				asy->asy_flags & ASY_IGNORE_CD,
1646 				asy->asy_flags & ASY_RTS_DTR_OFF);
1647 			ddi_put8(asy->asy_iohandle,
1648 				asy->asy_ioaddr + MCR, asy->asy_mcr|OUT2);
1649 		} else {
1650 			DEBUGCONT1(ASY_DEBUG_MODEM,
1651 			    "asy%dclose: Dropping DTR and RTS\n", instance);
1652 			ddi_put8(asy->asy_iohandle,
1653 				asy->asy_ioaddr + MCR, OUT2);
1654 		}
1655 		async->async_dtrtid =
1656 		    timeout((void (*)())async_dtr_free,
1657 		    (caddr_t)async, drv_usectohz(asy_min_dtr_low));
1658 	}
1659 	/*
1660 	 * If nobody's using it now, turn off receiver interrupts.
1661 	 */
1662 	if ((async->async_flags & (ASYNC_WOPEN|ASYNC_ISOPEN)) == 0) {
1663 		icr = ddi_get8(asy->asy_iohandle,
1664 			asy->asy_ioaddr + ICR);
1665 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR,
1666 			(icr & ~RIEN));
1667 	}
1668 	mutex_exit(&asy->asy_excl_hi);
1669 out:
1670 	ttycommon_close(&async->async_ttycommon);
1671 
1672 	/*
1673 	 * Cancel outstanding "bufcall" request.
1674 	 */
1675 	if (async->async_wbufcid != 0) {
1676 		unbufcall(async->async_wbufcid);
1677 		async->async_wbufcid = 0;
1678 	}
1679 
1680 	/* Note that qprocsoff can't be done until after interrupts are off */
1681 	qprocsoff(q);
1682 	q->q_ptr = WR(q)->q_ptr = NULL;
1683 	async->async_ttycommon.t_readq = NULL;
1684 	async->async_ttycommon.t_writeq = NULL;
1685 
1686 	/*
1687 	 * Clear out device state, except persistant device property flags.
1688 	 */
1689 	async->async_flags &= (ASYNC_DTR_DELAY|ASY_RTS_DTR_OFF);
1690 	cv_broadcast(&async->async_flags_cv);
1691 	mutex_exit(&asy->asy_excl);
1692 
1693 	DEBUGCONT1(ASY_DEBUG_CLOSE, "asy%dclose: done\n", instance);
1694 	return (0);
1695 }
1696 
1697 static boolean_t
1698 asy_isbusy(struct asycom *asy)
1699 {
1700 	struct asyncline *async;
1701 
1702 	DEBUGCONT0(ASY_DEBUG_EOT, "asy_isbusy\n");
1703 	async = asy->asy_priv;
1704 	ASSERT(mutex_owned(&asy->asy_excl));
1705 	ASSERT(mutex_owned(&asy->asy_excl_hi));
1706 	return ((async->async_ocnt > 0) ||
1707 		((ddi_get8(asy->asy_iohandle,
1708 		    asy->asy_ioaddr + LSR) & (XSRE|XHRE)) == 0));
1709 }
1710 
1711 static void
1712 asy_waiteot(struct asycom *asy)
1713 {
1714 	/*
1715 	 * Wait for the current transmission block and the
1716 	 * current fifo data to transmit. Once this is done
1717 	 * we may go on.
1718 	 */
1719 	DEBUGCONT0(ASY_DEBUG_EOT, "asy_waiteot\n");
1720 	ASSERT(mutex_owned(&asy->asy_excl));
1721 	ASSERT(mutex_owned(&asy->asy_excl_hi));
1722 	while (asy_isbusy(asy)) {
1723 		mutex_exit(&asy->asy_excl_hi);
1724 		mutex_exit(&asy->asy_excl);
1725 		drv_usecwait(10000);		/* wait .01 */
1726 		mutex_enter(&asy->asy_excl);
1727 		mutex_enter(&asy->asy_excl_hi);
1728 	}
1729 }
1730 
1731 /* asy_reset_fifo -- flush fifos and [re]program fifo control register */
1732 static void
1733 asy_reset_fifo(struct asycom *asy, uchar_t flush)
1734 {
1735 	uchar_t lcr;
1736 
1737 	/* On a 16750, we have to set DLAB in order to set FIFOEXTRA. */
1738 
1739 	if (asy->asy_hwtype >= ASY16750) {
1740 		lcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
1741 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
1742 		    lcr | DLAB);
1743 	}
1744 
1745 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + FIFOR,
1746 	    asy->asy_fifor | flush);
1747 
1748 	/* Clear DLAB */
1749 
1750 	if (asy->asy_hwtype >= ASY16750) {
1751 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, lcr);
1752 	}
1753 }
1754 
1755 /*
1756  * Program the ASY port. Most of the async operation is based on the values
1757  * of 'c_iflag' and 'c_cflag'.
1758  */
1759 
1760 #define	BAUDINDEX(cflg)	(((cflg) & CBAUDEXT) ? \
1761 			(((cflg) & CBAUD) + CBAUD + 1) : ((cflg) & CBAUD))
1762 
1763 static void
1764 asy_program(struct asycom *asy, int mode)
1765 {
1766 	struct asyncline *async;
1767 	int baudrate, c_flag;
1768 	int icr, lcr;
1769 	int flush_reg;
1770 	int ocflags;
1771 #ifdef DEBUG
1772 	int instance;
1773 #endif
1774 
1775 	ASSERT(mutex_owned(&asy->asy_excl));
1776 	ASSERT(mutex_owned(&asy->asy_excl_hi));
1777 
1778 	async = asy->asy_priv;
1779 #ifdef DEBUG
1780 	instance = UNIT(async->async_dev);
1781 	DEBUGCONT2(ASY_DEBUG_PROCS,
1782 		"asy%d_program: mode = 0x%08X, enter\n", instance, mode);
1783 #endif
1784 
1785 	baudrate = BAUDINDEX(async->async_ttycommon.t_cflag);
1786 
1787 	async->async_ttycommon.t_cflag &= ~(CIBAUD);
1788 
1789 	if (baudrate > CBAUD) {
1790 		async->async_ttycommon.t_cflag |= CIBAUDEXT;
1791 		async->async_ttycommon.t_cflag |=
1792 			(((baudrate - CBAUD - 1) << IBSHIFT) & CIBAUD);
1793 	} else {
1794 		async->async_ttycommon.t_cflag &= ~CIBAUDEXT;
1795 		async->async_ttycommon.t_cflag |=
1796 			((baudrate << IBSHIFT) & CIBAUD);
1797 	}
1798 
1799 	c_flag = async->async_ttycommon.t_cflag &
1800 		(CLOCAL|CREAD|CSTOPB|CSIZE|PARENB|PARODD|CBAUD|CBAUDEXT);
1801 
1802 	/* disable interrupts */
1803 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, 0);
1804 
1805 	ocflags = asy->asy_ocflag;
1806 
1807 	/* flush/reset the status registers */
1808 	(void) ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + ISR);
1809 	(void) ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR);
1810 	asy->asy_msr = flush_reg = ddi_get8(asy->asy_iohandle,
1811 					asy->asy_ioaddr + MSR);
1812 	/*
1813 	 * The device is programmed in the open sequence, if we
1814 	 * have to hardware handshake, then this is a good time
1815 	 * to check if the device can receive any data.
1816 	 */
1817 
1818 	if ((CRTSCTS & async->async_ttycommon.t_cflag) && !(flush_reg & CTS)) {
1819 		async_flowcontrol_hw_output(asy, FLOW_STOP);
1820 	} else {
1821 		/*
1822 		 * We can not use async_flowcontrol_hw_output(asy, FLOW_START)
1823 		 * here, because if CRTSCTS is clear, we need clear
1824 		 * ASYNC_HW_OUT_FLW bit.
1825 		 */
1826 		async->async_flags &= ~ASYNC_HW_OUT_FLW;
1827 	}
1828 
1829 	/*
1830 	 * If IXON is not set, clear ASYNC_SW_OUT_FLW;
1831 	 * If IXON is set, no matter what IXON flag is before this
1832 	 * function call to asy_program,
1833 	 * we will use the old ASYNC_SW_OUT_FLW status.
1834 	 * Because of handling IXON in the driver, we also should re-calculate
1835 	 * the value of ASYNC_OUT_FLW_RESUME bit, but in fact,
1836 	 * the TCSET* commands which call asy_program
1837 	 * are put into the write queue, so there is no output needed to
1838 	 * be resumed at this point.
1839 	 */
1840 	if (!(IXON & async->async_ttycommon.t_iflag))
1841 		async->async_flags &= ~ASYNC_SW_OUT_FLW;
1842 
1843 	/* manually flush receive buffer or fifo (workaround for buggy fifos) */
1844 	if (mode == ASY_INIT)
1845 		if (asy->asy_use_fifo == FIFO_ON) {
1846 			for (flush_reg = asy->asy_fifo_buf; flush_reg-- > 0; ) {
1847 				(void) ddi_get8(asy->asy_iohandle,
1848 						asy->asy_ioaddr + DAT);
1849 			}
1850 		} else {
1851 			flush_reg = ddi_get8(asy->asy_iohandle,
1852 					asy->asy_ioaddr + DAT);
1853 		}
1854 
1855 	if (ocflags != (c_flag & ~CLOCAL) || mode == ASY_INIT) {
1856 		/* Set line control */
1857 		lcr = ddi_get8(asy->asy_iohandle,
1858 			asy->asy_ioaddr + LCR);
1859 		lcr &= ~(WLS0|WLS1|STB|PEN|EPS);
1860 
1861 		if (c_flag & CSTOPB)
1862 			lcr |= STB;	/* 2 stop bits */
1863 
1864 		if (c_flag & PARENB)
1865 			lcr |= PEN;
1866 
1867 		if ((c_flag & PARODD) == 0)
1868 			lcr |= EPS;
1869 
1870 		switch (c_flag & CSIZE) {
1871 		case CS5:
1872 			lcr |= BITS5;
1873 			break;
1874 		case CS6:
1875 			lcr |= BITS6;
1876 			break;
1877 		case CS7:
1878 			lcr |= BITS7;
1879 			break;
1880 		case CS8:
1881 			lcr |= BITS8;
1882 			break;
1883 		}
1884 
1885 		/* set the baud rate, unless it is "0" */
1886 		ddi_put8(asy->asy_iohandle,
1887 			asy->asy_ioaddr + LCR, DLAB);
1888 		if (baudrate != 0) {
1889 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
1890 				asyspdtab[baudrate] & 0xff);
1891 			ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR,
1892 				(asyspdtab[baudrate] >> 8) & 0xff);
1893 		}
1894 		/* set the line control modes */
1895 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR, lcr);
1896 
1897 		/*
1898 		 * If we have a FIFO buffer, enable/flush
1899 		 * at intialize time, flush if transitioning from
1900 		 * CREAD off to CREAD on.
1901 		 */
1902 		if ((ocflags & CREAD) == 0 && (c_flag & CREAD) ||
1903 		    mode == ASY_INIT)
1904 			if (asy->asy_use_fifo == FIFO_ON)
1905 				asy_reset_fifo(asy, FIFORXFLSH);
1906 
1907 		/* remember the new cflags */
1908 		asy->asy_ocflag = c_flag & ~CLOCAL;
1909 	}
1910 
1911 	if (baudrate == 0)
1912 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1913 			(asy->asy_mcr & RTS) | OUT2);
1914 	else
1915 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR,
1916 			asy->asy_mcr | OUT2);
1917 
1918 	/*
1919 	 * Call the modem status interrupt handler to check for the carrier
1920 	 * in case CLOCAL was turned off after the carrier came on.
1921 	 * (Note: Modem status interrupt is not enabled if CLOCAL is ON.)
1922 	 */
1923 	async_msint(asy);
1924 
1925 	/* Set interrupt control */
1926 	DEBUGCONT3(ASY_DEBUG_MODM2,
1927 		"asy%d_program: c_flag & CLOCAL = %x t_cflag & CRTSCTS = %x\n",
1928 		instance,
1929 		c_flag & CLOCAL,
1930 		async->async_ttycommon.t_cflag & CRTSCTS);
1931 	if ((c_flag & CLOCAL) && !(async->async_ttycommon.t_cflag & CRTSCTS))
1932 		/*
1933 		 * direct-wired line ignores DCD, so we don't enable modem
1934 		 * status interrupts.
1935 		 */
1936 		icr = (TIEN | SIEN);
1937 	else
1938 		icr = (TIEN | SIEN | MIEN);
1939 
1940 	if (c_flag & CREAD)
1941 		icr |= RIEN;
1942 
1943 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + ICR, icr);
1944 	DEBUGCONT1(ASY_DEBUG_PROCS, "asy%d_program: done\n", instance);
1945 }
1946 
1947 static boolean_t
1948 asy_baudok(struct asycom *asy)
1949 {
1950 	struct asyncline *async = asy->asy_priv;
1951 	int baudrate;
1952 
1953 
1954 	baudrate = BAUDINDEX(async->async_ttycommon.t_cflag);
1955 
1956 	if (baudrate >= sizeof (asyspdtab)/sizeof (*asyspdtab))
1957 		return (0);
1958 
1959 	return (baudrate == 0 || asyspdtab[baudrate]);
1960 }
1961 
1962 /*
1963  * asyintr() is the High Level Interrupt Handler.
1964  *
1965  * There are four different interrupt types indexed by ISR register values:
1966  *		0: modem
1967  *		1: Tx holding register is empty, ready for next char
1968  *		2: Rx register now holds a char to be picked up
1969  *		3: error or break on line
1970  * This routine checks the Bit 0 (interrupt-not-pending) to determine if
1971  * the interrupt is from this port.
1972  */
1973 uint_t
1974 asyintr(caddr_t argasy)
1975 {
1976 	struct asycom		*asy = (struct asycom *)argasy;
1977 	struct asyncline	*async;
1978 	int			ret_status = DDI_INTR_UNCLAIMED;
1979 	uchar_t			interrupt_id, lsr;
1980 
1981 	interrupt_id = ddi_get8(asy->asy_iohandle,
1982 				asy->asy_ioaddr + ISR) & 0x0F;
1983 	async = asy->asy_priv;
1984 	if ((async == NULL) || asy_addedsoft == 0 ||
1985 		!(async->async_flags & (ASYNC_ISOPEN|ASYNC_WOPEN))) {
1986 		if (interrupt_id & NOINTERRUPT)
1987 			return (DDI_INTR_UNCLAIMED);
1988 		else {
1989 			/*
1990 			 * reset the device by:
1991 			 *	reading line status
1992 			 *	reading any data from data status register
1993 			 *	reading modem status
1994 			 */
1995 			(void) ddi_get8(asy->asy_iohandle,
1996 					asy->asy_ioaddr + LSR);
1997 			(void) ddi_get8(asy->asy_iohandle,
1998 					asy->asy_ioaddr + DAT);
1999 			asy->asy_msr = ddi_get8(asy->asy_iohandle,
2000 						asy->asy_ioaddr + MSR);
2001 			return (DDI_INTR_CLAIMED);
2002 		}
2003 	}
2004 	mutex_enter(&asy->asy_excl_hi);
2005 	/*
2006 	 * We will loop until the interrupt line is pulled low. asy
2007 	 * interrupt is edge triggered.
2008 	 */
2009 	/* CSTYLED */
2010 	for (;; interrupt_id = (ddi_get8(asy->asy_iohandle,
2011 					asy->asy_ioaddr + ISR) & 0x0F)) {
2012 		if (interrupt_id & NOINTERRUPT)
2013 			break;
2014 		ret_status = DDI_INTR_CLAIMED;
2015 
2016 		DEBUGCONT1(ASY_DEBUG_INTR,
2017 			"asyintr: interrupt_id = 0x%d\n", interrupt_id);
2018 		lsr = ddi_get8(asy->asy_iohandle,
2019 			asy->asy_ioaddr + LSR);
2020 		switch (interrupt_id) {
2021 		case RxRDY:
2022 		case RSTATUS:
2023 		case FFTMOUT:
2024 			/* receiver interrupt or receiver errors */
2025 			async_rxint(asy, lsr);
2026 			break;
2027 		case TxRDY:
2028 			/* transmit interrupt */
2029 			async_txint(asy);
2030 			continue;
2031 		case MSTATUS:
2032 			/* modem status interrupt */
2033 			async_msint(asy);
2034 			break;
2035 		}
2036 		if ((lsr & XHRE) && (async->async_flags & ASYNC_BUSY) &&
2037 		    (async->async_ocnt > 0))
2038 			async_txint(asy);
2039 	}
2040 	mutex_exit(&asy->asy_excl_hi);
2041 	return (ret_status);
2042 }
2043 
2044 /*
2045  * Transmitter interrupt service routine.
2046  * If there is more data to transmit in the current pseudo-DMA block,
2047  * send the next character if output is not stopped or draining.
2048  * Otherwise, queue up a soft interrupt.
2049  *
2050  * XXX -  Needs review for HW FIFOs.
2051  */
2052 static void
2053 async_txint(struct asycom *asy)
2054 {
2055 	struct asyncline *async = asy->asy_priv;
2056 	int		fifo_len;
2057 
2058 	/*
2059 	 * If ASYNC_BREAK or ASYNC_OUT_SUSPEND has been set, return to
2060 	 * asyintr()'s context to claim the interrupt without performing
2061 	 * any action. No character will be loaded into FIFO/THR until
2062 	 * timed or untimed break is removed
2063 	 */
2064 	if (async->async_flags & (ASYNC_BREAK|ASYNC_OUT_SUSPEND))
2065 		return;
2066 
2067 	fifo_len = asy->asy_fifo_buf; /* with FIFO buffers */
2068 	if (fifo_len > asy_max_tx_fifo)
2069 		fifo_len = asy_max_tx_fifo;
2070 
2071 	if (async_flowcontrol_sw_input(asy, FLOW_CHECK, IN_FLOW_NULL))
2072 		fifo_len--;
2073 
2074 	if (async->async_ocnt > 0 && fifo_len > 0 &&
2075 	    !(async->async_flags &
2076 	    (ASYNC_HW_OUT_FLW|ASYNC_SW_OUT_FLW|ASYNC_STOPPED))) {
2077 		while (fifo_len-- > 0 && async->async_ocnt-- > 0) {
2078 			ddi_put8(asy->asy_iohandle,
2079 			    asy->asy_ioaddr + DAT, *async->async_optr++);
2080 		}
2081 		async->async_flags |= ASYNC_PROGRESS;
2082 	}
2083 
2084 	if (fifo_len <= 0)
2085 		return;
2086 
2087 	ASYSETSOFT(asy);
2088 }
2089 
2090 /*
2091  * Interrupt on port: handle PPS event.  This function is only called
2092  * for a port on which PPS event handling has been enabled.
2093  */
2094 static void
2095 asy_ppsevent(struct asycom *asy, int msr)
2096 {
2097 	if (asy->asy_flags & ASY_PPS_EDGE) {
2098 		/* Have seen leading edge, now look for and record drop */
2099 		if ((msr & DCD) == 0)
2100 			asy->asy_flags &= ~ASY_PPS_EDGE;
2101 		/*
2102 		 * Waiting for leading edge, look for rise; stamp event and
2103 		 * calibrate kernel clock.
2104 		 */
2105 	} else if (msr & DCD) {
2106 			/*
2107 			 * This code captures a timestamp at the designated
2108 			 * transition of the PPS signal (DCD asserted).  The
2109 			 * code provides a pointer to the timestamp, as well
2110 			 * as the hardware counter value at the capture.
2111 			 *
2112 			 * Note: the kernel has nano based time values while
2113 			 * NTP requires micro based, an in-line fast algorithm
2114 			 * to convert nsec to usec is used here -- see hrt2ts()
2115 			 * in common/os/timers.c for a full description.
2116 			 */
2117 			struct timeval *tvp = &asy_ppsev.tv;
2118 			timestruc_t ts;
2119 			long nsec, usec;
2120 
2121 			asy->asy_flags |= ASY_PPS_EDGE;
2122 			LED_OFF;
2123 			gethrestime(&ts);
2124 			LED_ON;
2125 			nsec = ts.tv_nsec;
2126 			usec = nsec + (nsec >> 2);
2127 			usec = nsec + (usec >> 1);
2128 			usec = nsec + (usec >> 2);
2129 			usec = nsec + (usec >> 4);
2130 			usec = nsec - (usec >> 3);
2131 			usec = nsec + (usec >> 2);
2132 			usec = nsec + (usec >> 3);
2133 			usec = nsec + (usec >> 4);
2134 			usec = nsec + (usec >> 1);
2135 			usec = nsec + (usec >> 6);
2136 			tvp->tv_usec = usec >> 10;
2137 			tvp->tv_sec = ts.tv_sec;
2138 
2139 			++asy_ppsev.serial;
2140 
2141 			/*
2142 			 * Because the kernel keeps a high-resolution time,
2143 			 * pass the current highres timestamp in tvp and zero
2144 			 * in usec.
2145 			 */
2146 			ddi_hardpps(tvp, 0);
2147 	}
2148 }
2149 
2150 /*
2151  * Receiver interrupt: RxRDY interrupt, FIFO timeout interrupt or receive
2152  * error interrupt.
2153  * Try to put the character into the circular buffer for this line; if it
2154  * overflows, indicate a circular buffer overrun. If this port is always
2155  * to be serviced immediately, or the character is a STOP character, or
2156  * more than 15 characters have arrived, queue up a soft interrupt to
2157  * drain the circular buffer.
2158  * XXX - needs review for hw FIFOs support.
2159  */
2160 
2161 static void
2162 async_rxint(struct asycom *asy, uchar_t lsr)
2163 {
2164 	struct asyncline *async = asy->asy_priv;
2165 	uchar_t c;
2166 	uint_t s, needsoft = 0;
2167 	tty_common_t *tp;
2168 	int looplim = asy->asy_fifo_buf * 2;
2169 
2170 	tp = &async->async_ttycommon;
2171 	if (!(tp->t_cflag & CREAD)) {
2172 		while (lsr & (RCA|PARERR|FRMERR|BRKDET|OVRRUN)) {
2173 			(void) (ddi_get8(asy->asy_iohandle,
2174 					asy->asy_ioaddr + DAT) & 0xff);
2175 			lsr = ddi_get8(asy->asy_iohandle,
2176 					asy->asy_ioaddr + LSR);
2177 			if (looplim-- < 0)		/* limit loop */
2178 				break;
2179 		}
2180 		return; /* line is not open for read? */
2181 	}
2182 
2183 	while (lsr & (RCA|PARERR|FRMERR|BRKDET|OVRRUN)) {
2184 		c = 0;
2185 		s = 0;				/* reset error status */
2186 		if (lsr & RCA) {
2187 			c = ddi_get8(asy->asy_iohandle,
2188 				asy->asy_ioaddr + DAT) & 0xff;
2189 
2190 			/*
2191 			 * We handle XON/XOFF char if IXON is set,
2192 			 * but if received char is _POSIX_VDISABLE,
2193 			 * we left it to the up level module.
2194 			 */
2195 			if (tp->t_iflag & IXON) {
2196 				if ((c == async->async_stopc) &&
2197 				    (c != _POSIX_VDISABLE)) {
2198 					async_flowcontrol_sw_output(asy,
2199 					    FLOW_STOP);
2200 					goto check_looplim;
2201 				} else if ((c == async->async_startc) &&
2202 				    (c != _POSIX_VDISABLE)) {
2203 					async_flowcontrol_sw_output(asy,
2204 					    FLOW_START);
2205 					needsoft = 1;
2206 					goto check_looplim;
2207 				}
2208 				if ((tp->t_iflag & IXANY) &&
2209 				    (async->async_flags & ASYNC_SW_OUT_FLW)) {
2210 					async_flowcontrol_sw_output(asy,
2211 					    FLOW_START);
2212 					needsoft = 1;
2213 				}
2214 			}
2215 		}
2216 
2217 		/*
2218 		 * Check for character break sequence
2219 		 */
2220 		if ((abort_enable == KIOCABORTALTERNATE) &&
2221 		    (asy->asy_flags & ASY_CONSOLE)) {
2222 			if (abort_charseq_recognize(c))
2223 				abort_sequence_enter((char *)NULL);
2224 		}
2225 
2226 		/* Handle framing errors */
2227 		if (lsr & (PARERR|FRMERR|BRKDET|OVRRUN)) {
2228 			if (lsr & PARERR) {
2229 				if (tp->t_iflag & INPCK) /* parity enabled */
2230 					s |= PERROR;
2231 			}
2232 
2233 			if (lsr & (FRMERR|BRKDET))
2234 				s |= FRERROR;
2235 			if (lsr & OVRRUN) {
2236 				async->async_hw_overrun = 1;
2237 				s |= OVERRUN;
2238 			}
2239 		}
2240 
2241 		if (s == 0)
2242 			if ((tp->t_iflag & PARMRK) &&
2243 			    !(tp->t_iflag & (IGNPAR|ISTRIP)) &&
2244 			    (c == 0377))
2245 				if (RING_POK(async, 2)) {
2246 					RING_PUT(async, 0377);
2247 					RING_PUT(async, c);
2248 				} else
2249 					async->async_sw_overrun = 1;
2250 			else
2251 				if (RING_POK(async, 1))
2252 					RING_PUT(async, c);
2253 				else
2254 					async->async_sw_overrun = 1;
2255 		else
2256 			if (s & FRERROR) /* Handle framing errors */
2257 				if (c == 0)
2258 					if ((asy->asy_flags & ASY_CONSOLE) &&
2259 					    (abort_enable !=
2260 					    KIOCABORTALTERNATE))
2261 						abort_sequence_enter((char *)0);
2262 					else
2263 						async->async_break++;
2264 				else
2265 					if (RING_POK(async, 1))
2266 						RING_MARK(async, c, s);
2267 					else
2268 						async->async_sw_overrun = 1;
2269 			else /* Parity errors are handled by ldterm */
2270 				if (RING_POK(async, 1))
2271 					RING_MARK(async, c, s);
2272 				else
2273 					async->async_sw_overrun = 1;
2274 check_looplim:
2275 		lsr = ddi_get8(asy->asy_iohandle,
2276 			asy->asy_ioaddr + LSR);
2277 		if (looplim-- < 0)		/* limit loop */
2278 			break;
2279 	}
2280 	if ((RING_CNT(async) > (RINGSIZE * 3)/4) &&
2281 	    !(async->async_inflow_source & IN_FLOW_RINGBUFF)) {
2282 		async_flowcontrol_hw_input(asy, FLOW_STOP, IN_FLOW_RINGBUFF);
2283 		(void) async_flowcontrol_sw_input(asy, FLOW_STOP,
2284 		    IN_FLOW_RINGBUFF);
2285 	}
2286 
2287 	if ((async->async_flags & ASYNC_SERVICEIMM) || needsoft ||
2288 	    (RING_FRAC(async)) || (async->async_polltid == 0))
2289 		ASYSETSOFT(asy);	/* need a soft interrupt */
2290 }
2291 
2292 /*
2293  * Modem status interrupt.
2294  *
2295  * (Note: It is assumed that the MSR hasn't been read by asyintr().)
2296  */
2297 
2298 static void
2299 async_msint(struct asycom *asy)
2300 {
2301 	struct asyncline *async = asy->asy_priv;
2302 	int msr, t_cflag = async->async_ttycommon.t_cflag;
2303 #ifdef DEBUG
2304 	int instance = UNIT(async->async_dev);
2305 #endif
2306 
2307 async_msint_retry:
2308 	/* this resets the interrupt */
2309 	msr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MSR);
2310 	DEBUGCONT10(ASY_DEBUG_STATE,
2311 		"async%d_msint call #%d:\n"
2312 		"   transition: %3s %3s %3s %3s\n"
2313 		"current state: %3s %3s %3s %3s\n",
2314 		instance,
2315 		++(asy->asy_msint_cnt),
2316 		(msr & DCTS) ? "DCTS" : "    ",
2317 		(msr & DDSR) ? "DDSR" : "    ",
2318 		(msr & DRI)  ? "DRI " : "    ",
2319 		(msr & DDCD) ? "DDCD" : "    ",
2320 		(msr & CTS)  ? "CTS " : "    ",
2321 		(msr & DSR)  ? "DSR " : "    ",
2322 		(msr & RI)   ? "RI  " : "    ",
2323 		(msr & DCD)  ? "DCD " : "    ");
2324 
2325 	/* If CTS status is changed, do H/W output flow control */
2326 	if ((t_cflag & CRTSCTS) && (((asy->asy_msr ^ msr) & CTS) != 0))
2327 		async_flowcontrol_hw_output(asy,
2328 		    msr & CTS ? FLOW_START : FLOW_STOP);
2329 	/*
2330 	 * Reading MSR resets the interrupt, we save the
2331 	 * value of msr so that other functions could examine MSR by
2332 	 * looking at asy_msr.
2333 	 */
2334 	asy->asy_msr = (uchar_t)msr;
2335 
2336 	/* Handle PPS event */
2337 	if (asy->asy_flags & ASY_PPS)
2338 		asy_ppsevent(asy, msr);
2339 
2340 	async->async_ext++;
2341 	ASYSETSOFT(asy);
2342 	/*
2343 	 * We will make sure that the modem status presented to us
2344 	 * during the previous read has not changed. If the chip samples
2345 	 * the modem status on the falling edge of the interrupt line,
2346 	 * and uses this state as the base for detecting change of modem
2347 	 * status, we would miss a change of modem status event that occured
2348 	 * after we initiated a read MSR operation.
2349 	 */
2350 	msr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MSR);
2351 	if (STATES(msr) != STATES(asy->asy_msr))
2352 		goto	async_msint_retry;
2353 }
2354 
2355 /*
2356  * Handle a second-stage interrupt.
2357  */
2358 /*ARGSUSED*/
2359 uint_t
2360 asysoftintr(caddr_t intarg)
2361 {
2362 	struct asycom *asy;
2363 	int rv;
2364 	int instance;
2365 
2366 	/*
2367 	 * Test and clear soft interrupt.
2368 	 */
2369 	mutex_enter(&asy_soft_lock);
2370 	DEBUGCONT0(ASY_DEBUG_PROCS, "asysoftintr: enter\n");
2371 	rv = asysoftpend;
2372 	if (rv != 0)
2373 		asysoftpend = 0;
2374 	mutex_exit(&asy_soft_lock);
2375 
2376 	if (rv) {
2377 		/*
2378 		 * Note - we can optimize the loop by remembering the last
2379 		 * device that requested soft interrupt
2380 		 */
2381 		for (instance = 0; instance <= max_asy_instance; instance++) {
2382 			asy = ddi_get_soft_state(asy_soft_state, instance);
2383 			if (asy == NULL || asy->asy_priv == NULL)
2384 				continue;
2385 			mutex_enter(&asy_soft_lock);
2386 			if (asy->asy_flags & ASY_NEEDSOFT) {
2387 				asy->asy_flags &= ~ASY_NEEDSOFT;
2388 				mutex_exit(&asy_soft_lock);
2389 				async_softint(asy);
2390 			} else
2391 				mutex_exit(&asy_soft_lock);
2392 		}
2393 	}
2394 	return (rv ? DDI_INTR_CLAIMED : DDI_INTR_UNCLAIMED);
2395 }
2396 
2397 /*
2398  * Handle a software interrupt.
2399  */
2400 static void
2401 async_softint(struct asycom *asy)
2402 {
2403 	struct asyncline *async = asy->asy_priv;
2404 	short	cc;
2405 	mblk_t	*bp;
2406 	queue_t	*q;
2407 	uchar_t	val;
2408 	uchar_t	c;
2409 	tty_common_t	*tp;
2410 	int nb;
2411 	int instance = UNIT(async->async_dev);
2412 
2413 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_softint\n", instance);
2414 	mutex_enter(&asy_soft_lock);
2415 	if (asy->asy_flags & ASY_DOINGSOFT) {
2416 		asy->asy_flags |= ASY_DOINGSOFT_RETRY;
2417 		mutex_exit(&asy_soft_lock);
2418 		return;
2419 	}
2420 	asy->asy_flags |= ASY_DOINGSOFT;
2421 begin:
2422 	asy->asy_flags &= ~ASY_DOINGSOFT_RETRY;
2423 	mutex_exit(&asy_soft_lock);
2424 	mutex_enter(&asy->asy_excl);
2425 	tp = &async->async_ttycommon;
2426 	q = tp->t_readq;
2427 	if (async->async_flags & ASYNC_OUT_FLW_RESUME) {
2428 		if (async->async_ocnt > 0) {
2429 			mutex_enter(&asy->asy_excl_hi);
2430 			async_resume(async);
2431 			mutex_exit(&asy->asy_excl_hi);
2432 		} else {
2433 			if (async->async_xmitblk)
2434 				freeb(async->async_xmitblk);
2435 			async->async_xmitblk = NULL;
2436 			async_start(async);
2437 		}
2438 		async->async_flags &= ~ASYNC_OUT_FLW_RESUME;
2439 	}
2440 	mutex_enter(&asy->asy_excl_hi);
2441 	if (async->async_ext) {
2442 		async->async_ext = 0;
2443 		/* check for carrier up */
2444 		DEBUGCONT3(ASY_DEBUG_MODM2,
2445 			"async%d_softint: asy_msr & DCD = %x, "
2446 			"tp->t_flags & TS_SOFTCAR = %x\n",
2447 			instance,
2448 			asy->asy_msr & DCD,
2449 			tp->t_flags & TS_SOFTCAR);
2450 		if (asy->asy_msr & DCD) {
2451 			/* carrier present */
2452 			if ((async->async_flags & ASYNC_CARR_ON) == 0) {
2453 				DEBUGCONT1(ASY_DEBUG_MODM2,
2454 					"async%d_softint: set ASYNC_CARR_ON\n",
2455 					instance);
2456 				async->async_flags |= ASYNC_CARR_ON;
2457 				if (async->async_flags & ASYNC_ISOPEN) {
2458 					mutex_exit(&asy->asy_excl_hi);
2459 					mutex_exit(&asy->asy_excl);
2460 					(void) putctl(q, M_UNHANGUP);
2461 					mutex_enter(&asy->asy_excl);
2462 					mutex_enter(&asy->asy_excl_hi);
2463 				}
2464 				cv_broadcast(&async->async_flags_cv);
2465 			}
2466 		} else {
2467 			if ((async->async_flags & ASYNC_CARR_ON) &&
2468 			    !(tp->t_cflag & CLOCAL) &&
2469 			    !(tp->t_flags & TS_SOFTCAR)) {
2470 				int flushflag;
2471 
2472 				DEBUGCONT1(ASY_DEBUG_MODEM,
2473 					"async%d_softint: carrier dropped, "
2474 					"so drop DTR\n",
2475 					instance);
2476 				/*
2477 				 * Carrier went away.
2478 				 * Drop DTR, abort any output in
2479 				 * progress, indicate that output is
2480 				 * not stopped, and send a hangup
2481 				 * notification upstream.
2482 				 */
2483 				val = ddi_get8(asy->asy_iohandle,
2484 					asy->asy_ioaddr + MCR);
2485 				ddi_put8(asy->asy_iohandle,
2486 				    asy->asy_ioaddr + MCR, (val & ~DTR));
2487 				if (async->async_flags & ASYNC_BUSY) {
2488 				    DEBUGCONT0(ASY_DEBUG_BUSY,
2489 					    "async_softint: "
2490 					    "Carrier dropped.  "
2491 					    "Clearing async_ocnt\n");
2492 				    async->async_ocnt = 0;
2493 				}	/* if */
2494 
2495 				async->async_flags &= ~ASYNC_STOPPED;
2496 				if (async->async_flags & ASYNC_ISOPEN) {
2497 				    mutex_exit(&asy->asy_excl_hi);
2498 				    mutex_exit(&asy->asy_excl);
2499 				    (void) putctl(q, M_HANGUP);
2500 				    mutex_enter(&asy->asy_excl);
2501 				DEBUGCONT1(ASY_DEBUG_MODEM,
2502 					"async%d_softint: "
2503 					"putctl(q, M_HANGUP)\n",
2504 					instance);
2505 				/*
2506 				 * Flush FIFO buffers
2507 				 * Any data left in there is invalid now
2508 				 */
2509 				if (asy->asy_use_fifo == FIFO_ON)
2510 					asy_reset_fifo(asy, FIFOTXFLSH);
2511 				/*
2512 				 * Flush our write queue if we have one.
2513 				 *
2514 				 * If we're in the midst of close, then flush
2515 				 * everything.  Don't leave stale ioctls lying
2516 				 * about.
2517 				 */
2518 				flushflag = (async->async_flags &
2519 				    ASYNC_CLOSING) ? FLUSHALL : FLUSHDATA;
2520 				flushq(tp->t_writeq, flushflag);
2521 
2522 				bp = async->async_xmitblk; /* active msg */
2523 				if (bp != NULL) {
2524 					freeb(bp);
2525 					async->async_xmitblk = NULL;
2526 				}
2527 
2528 				mutex_enter(&asy->asy_excl_hi);
2529 				async->async_flags &= ~ASYNC_BUSY;
2530 				/*
2531 				 * This message warns of Carrier loss
2532 				 * with data left to transmit can hang the
2533 				 * system.
2534 				 */
2535 				DEBUGCONT0(ASY_DEBUG_MODEM,
2536 					"async_softint: Flushing to "
2537 					"prevent HUPCL hanging\n");
2538 				}	/* if (ASYNC_ISOPEN) */
2539 			}	/* if (ASYNC_CARR_ON && CLOCAL) */
2540 			async->async_flags &= ~ASYNC_CARR_ON;
2541 			cv_broadcast(&async->async_flags_cv);
2542 		}	/* else */
2543 	}	/* if (async->async_ext) */
2544 
2545 	mutex_exit(&asy->asy_excl_hi);
2546 
2547 	/*
2548 	 * If data has been added to the circular buffer, remove
2549 	 * it from the buffer, and send it up the stream if there's
2550 	 * somebody listening. Try to do it 16 bytes at a time. If we
2551 	 * have more than 16 bytes to move, move 16 byte chunks and
2552 	 * leave the rest for next time around (maybe it will grow).
2553 	 */
2554 	mutex_enter(&asy->asy_excl_hi);
2555 	if (!(async->async_flags & ASYNC_ISOPEN)) {
2556 		RING_INIT(async);
2557 		goto rv;
2558 	}
2559 	if ((cc = RING_CNT(async)) <= 0)
2560 		goto rv;
2561 	mutex_exit(&asy->asy_excl_hi);
2562 
2563 	if (!canput(q)) {
2564 		mutex_enter(&asy->asy_excl_hi);
2565 		if (!(async->async_inflow_source & IN_FLOW_STREAMS)) {
2566 			async_flowcontrol_hw_input(asy, FLOW_STOP,
2567 			    IN_FLOW_STREAMS);
2568 			(void) async_flowcontrol_sw_input(asy, FLOW_STOP,
2569 			    IN_FLOW_STREAMS);
2570 		}
2571 		goto rv;
2572 	}
2573 	if (async->async_inflow_source & IN_FLOW_STREAMS) {
2574 		mutex_enter(&asy->asy_excl_hi);
2575 		async_flowcontrol_hw_input(asy, FLOW_START,
2576 		    IN_FLOW_STREAMS);
2577 		(void) async_flowcontrol_sw_input(asy, FLOW_START,
2578 		    IN_FLOW_STREAMS);
2579 		mutex_exit(&asy->asy_excl_hi);
2580 	}
2581 	DEBUGCONT2(ASY_DEBUG_INPUT,
2582 		"async%d_softint: %d char(s) in queue.\n", instance, cc);
2583 	if (!(bp = allocb(cc, BPRI_MED))) {
2584 		mutex_exit(&asy->asy_excl);
2585 		ttycommon_qfull(&async->async_ttycommon, q);
2586 		mutex_enter(&asy->asy_excl);
2587 		mutex_enter(&asy->asy_excl_hi);
2588 		goto rv;
2589 	}
2590 	mutex_enter(&asy->asy_excl_hi);
2591 	do {
2592 		if (RING_ERR(async, S_ERRORS)) {
2593 			RING_UNMARK(async);
2594 			c = RING_GET(async);
2595 			break;
2596 		} else
2597 			*bp->b_wptr++ = RING_GET(async);
2598 	} while (--cc);
2599 	mutex_exit(&asy->asy_excl_hi);
2600 	mutex_exit(&asy->asy_excl);
2601 	if (bp->b_wptr > bp->b_rptr) {
2602 			if (!canput(q)) {
2603 				asyerror(CE_NOTE, "asy%d: local queue full",
2604 					instance);
2605 				freemsg(bp);
2606 			} else
2607 				(void) putq(q, bp);
2608 	} else
2609 		freemsg(bp);
2610 	/*
2611 	 * If we have a parity error, then send
2612 	 * up an M_BREAK with the "bad"
2613 	 * character as an argument. Let ldterm
2614 	 * figure out what to do with the error.
2615 	 */
2616 	if (cc) {
2617 		(void) putctl1(q, M_BREAK, c);
2618 		ASYSETSOFT(async->async_common);	/* finish cc chars */
2619 	}
2620 	mutex_enter(&asy->asy_excl);
2621 	mutex_enter(&asy->asy_excl_hi);
2622 rv:
2623 	if ((RING_CNT(async) < (RINGSIZE/4)) &&
2624 	    (async->async_inflow_source & IN_FLOW_RINGBUFF)) {
2625 		async_flowcontrol_hw_input(asy, FLOW_START, IN_FLOW_RINGBUFF);
2626 		(void) async_flowcontrol_sw_input(asy, FLOW_START,
2627 		    IN_FLOW_RINGBUFF);
2628 	}
2629 
2630 	/*
2631 	 * If a transmission has finished, indicate that it's finished,
2632 	 * and start that line up again.
2633 	 */
2634 	if (async->async_break > 0) {
2635 		nb = async->async_break;
2636 		async->async_break = 0;
2637 		if (async->async_flags & ASYNC_ISOPEN) {
2638 			mutex_exit(&asy->asy_excl_hi);
2639 			mutex_exit(&asy->asy_excl);
2640 			for (; nb > 0; nb--)
2641 				(void) putctl(q, M_BREAK);
2642 			mutex_enter(&asy->asy_excl);
2643 			mutex_enter(&asy->asy_excl_hi);
2644 		}
2645 	}
2646 	if (async->async_ocnt <= 0 && (async->async_flags & ASYNC_BUSY)) {
2647 		DEBUGCONT2(ASY_DEBUG_BUSY,
2648 		    "async%d_softint: Clearing ASYNC_BUSY.  async_ocnt=%d\n",
2649 		    instance,
2650 		    async->async_ocnt);
2651 		async->async_flags &= ~ASYNC_BUSY;
2652 		mutex_exit(&asy->asy_excl_hi);
2653 		if (async->async_xmitblk)
2654 			freeb(async->async_xmitblk);
2655 		async->async_xmitblk = NULL;
2656 		async_start(async);
2657 		/*
2658 		 * If the flag isn't set after doing the async_start above, we
2659 		 * may have finished all the queued output.  Signal any thread
2660 		 * stuck in close.
2661 		 */
2662 		if (!(async->async_flags & ASYNC_BUSY))
2663 			cv_broadcast(&async->async_flags_cv);
2664 		mutex_enter(&asy->asy_excl_hi);
2665 	}
2666 	/*
2667 	 * A note about these overrun bits: all they do is *tell* someone
2668 	 * about an error- They do not track multiple errors. In fact,
2669 	 * you could consider them latched register bits if you like.
2670 	 * We are only interested in printing the error message once for
2671 	 * any cluster of overrun errrors.
2672 	 */
2673 	if (async->async_hw_overrun) {
2674 		if (async->async_flags & ASYNC_ISOPEN) {
2675 			mutex_exit(&asy->asy_excl_hi);
2676 			mutex_exit(&asy->asy_excl);
2677 			asyerror(CE_NOTE, "asy%d: silo overflow", instance);
2678 			mutex_enter(&asy->asy_excl);
2679 			mutex_enter(&asy->asy_excl_hi);
2680 		}
2681 		async->async_hw_overrun = 0;
2682 	}
2683 	if (async->async_sw_overrun) {
2684 		if (async->async_flags & ASYNC_ISOPEN) {
2685 			mutex_exit(&asy->asy_excl_hi);
2686 			mutex_exit(&asy->asy_excl);
2687 			asyerror(CE_NOTE, "asy%d: ring buffer overflow",
2688 				instance);
2689 			mutex_enter(&asy->asy_excl);
2690 			mutex_enter(&asy->asy_excl_hi);
2691 		}
2692 		async->async_sw_overrun = 0;
2693 	}
2694 	mutex_exit(&asy->asy_excl_hi);
2695 	mutex_exit(&asy->asy_excl);
2696 	mutex_enter(&asy_soft_lock);
2697 	if (asy->asy_flags & ASY_DOINGSOFT_RETRY) {
2698 		goto begin;
2699 	}
2700 	asy->asy_flags &= ~ASY_DOINGSOFT;
2701 	mutex_exit(&asy_soft_lock);
2702 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_softint: done\n", instance);
2703 }
2704 
2705 /*
2706  * Restart output on a line after a delay or break timer expired.
2707  */
2708 static void
2709 async_restart(void *arg)
2710 {
2711 	struct asyncline *async = (struct asyncline *)arg;
2712 	struct asycom *asy = async->async_common;
2713 	uchar_t lcr;
2714 
2715 	/*
2716 	 * If break timer expired, turn off the break bit.
2717 	 */
2718 #ifdef DEBUG
2719 	int instance = UNIT(async->async_dev);
2720 
2721 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_restart\n", instance);
2722 #endif
2723 	mutex_enter(&asy->asy_excl);
2724 	/*
2725 	 * If ASYNC_OUT_SUSPEND is also set, we don't really
2726 	 * clean the HW break, TIOCCBRK is responsible for this.
2727 	 */
2728 	if ((async->async_flags & ASYNC_BREAK) &&
2729 	    !(async->async_flags & ASYNC_OUT_SUSPEND)) {
2730 		mutex_enter(&asy->asy_excl_hi);
2731 		lcr = ddi_get8(asy->asy_iohandle,
2732 			asy->asy_ioaddr + LCR);
2733 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
2734 			(lcr & ~SETBREAK));
2735 		mutex_exit(&asy->asy_excl_hi);
2736 	}
2737 	async->async_flags &= ~(ASYNC_DELAY|ASYNC_BREAK);
2738 	cv_broadcast(&async->async_flags_cv);
2739 	async_start(async);
2740 
2741 	mutex_exit(&asy->asy_excl);
2742 }
2743 
2744 static void
2745 async_start(struct asyncline *async)
2746 {
2747 	async_nstart(async, 0);
2748 }
2749 
2750 /*
2751  * Start output on a line, unless it's busy, frozen, or otherwise.
2752  */
2753 /*ARGSUSED*/
2754 static void
2755 async_nstart(struct asyncline *async, int mode)
2756 {
2757 	struct asycom *asy = async->async_common;
2758 	int cc;
2759 	queue_t *q;
2760 	mblk_t *bp;
2761 	uchar_t *xmit_addr;
2762 	uchar_t	val;
2763 	int	fifo_len = 1;
2764 	boolean_t didsome;
2765 	mblk_t *nbp;
2766 
2767 #ifdef DEBUG
2768 	int instance = UNIT(async->async_dev);
2769 
2770 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_nstart\n", instance);
2771 #endif
2772 	if (asy->asy_use_fifo == FIFO_ON) {
2773 		fifo_len = asy->asy_fifo_buf; /* with FIFO buffers */
2774 		if (fifo_len > asy_max_tx_fifo)
2775 			fifo_len = asy_max_tx_fifo;
2776 	}
2777 
2778 	ASSERT(mutex_owned(&asy->asy_excl));
2779 
2780 	/*
2781 	 * If the chip is busy (i.e., we're waiting for a break timeout
2782 	 * to expire, or for the current transmission to finish, or for
2783 	 * output to finish draining from chip), don't grab anything new.
2784 	 */
2785 	if (async->async_flags & (ASYNC_BREAK|ASYNC_BUSY)) {
2786 		DEBUGCONT2((mode? ASY_DEBUG_OUT : 0),
2787 			"async%d_nstart: start %s.\n",
2788 			instance,
2789 			async->async_flags & ASYNC_BREAK ? "break" : "busy");
2790 		return;
2791 	}
2792 
2793 	/*
2794 	 * Check only pended sw input flow control.
2795 	 */
2796 	mutex_enter(&asy->asy_excl_hi);
2797 	if (async_flowcontrol_sw_input(asy, FLOW_CHECK, IN_FLOW_NULL))
2798 		fifo_len--;
2799 	mutex_exit(&asy->asy_excl_hi);
2800 
2801 	/*
2802 	 * If we're waiting for a delay timeout to expire, don't grab
2803 	 * anything new.
2804 	 */
2805 	if (async->async_flags & ASYNC_DELAY) {
2806 		DEBUGCONT1((mode? ASY_DEBUG_OUT : 0),
2807 			"async%d_nstart: start ASYNC_DELAY.\n", instance);
2808 		return;
2809 	}
2810 
2811 	if ((q = async->async_ttycommon.t_writeq) == NULL) {
2812 		DEBUGCONT1((mode? ASY_DEBUG_OUT : 0),
2813 			"async%d_nstart: start writeq is null.\n", instance);
2814 		return;	/* not attached to a stream */
2815 	}
2816 
2817 	for (;;) {
2818 		if ((bp = getq(q)) == NULL)
2819 			return;	/* no data to transmit */
2820 
2821 		/*
2822 		 * We have a message block to work on.
2823 		 * Check whether it's a break, a delay, or an ioctl (the latter
2824 		 * occurs if the ioctl in question was waiting for the output
2825 		 * to drain).  If it's one of those, process it immediately.
2826 		 */
2827 		switch (bp->b_datap->db_type) {
2828 
2829 		case M_BREAK:
2830 			/*
2831 			 * Set the break bit, and arrange for "async_restart"
2832 			 * to be called in 1/4 second; it will turn the
2833 			 * break bit off, and call "async_start" to grab
2834 			 * the next message.
2835 			 */
2836 			mutex_enter(&asy->asy_excl_hi);
2837 			val = ddi_get8(asy->asy_iohandle,
2838 				asy->asy_ioaddr + LCR);
2839 			ddi_put8(asy->asy_iohandle,
2840 				asy->asy_ioaddr + LCR, (val | SETBREAK));
2841 			mutex_exit(&asy->asy_excl_hi);
2842 			async->async_flags |= ASYNC_BREAK;
2843 			(void) timeout(async_restart, (caddr_t)async,
2844 			    drv_usectohz(1000000)/4);
2845 			freemsg(bp);
2846 			return;	/* wait for this to finish */
2847 
2848 		case M_DELAY:
2849 			/*
2850 			 * Arrange for "async_restart" to be called when the
2851 			 * delay expires; it will turn ASYNC_DELAY off,
2852 			 * and call "async_start" to grab the next message.
2853 			 */
2854 			(void) timeout(async_restart, (caddr_t)async,
2855 			    (int)(*(unsigned char *)bp->b_rptr + 6));
2856 			async->async_flags |= ASYNC_DELAY;
2857 			freemsg(bp);
2858 			return;	/* wait for this to finish */
2859 
2860 		case M_IOCTL:
2861 			/*
2862 			 * This ioctl was waiting for the output ahead of
2863 			 * it to drain; obviously, it has.  Do it, and
2864 			 * then grab the next message after it.
2865 			 */
2866 			mutex_exit(&asy->asy_excl);
2867 			async_ioctl(async, q, bp);
2868 			mutex_enter(&asy->asy_excl);
2869 			continue;
2870 		}
2871 
2872 		while (bp != NULL && (cc = bp->b_wptr - bp->b_rptr) == 0) {
2873 			nbp = bp->b_cont;
2874 			freeb(bp);
2875 			bp = nbp;
2876 		}
2877 		if (bp != NULL)
2878 			break;
2879 	}
2880 
2881 	/*
2882 	 * We have data to transmit.  If output is stopped, put
2883 	 * it back and try again later.
2884 	 */
2885 	if (async->async_flags & (ASYNC_HW_OUT_FLW | ASYNC_SW_OUT_FLW |
2886 	    ASYNC_STOPPED | ASYNC_OUT_SUSPEND)) {
2887 		(void) putbq(q, bp);
2888 		return;
2889 	}
2890 
2891 	async->async_xmitblk = bp;
2892 	xmit_addr = bp->b_rptr;
2893 	bp = bp->b_cont;
2894 	if (bp != NULL)
2895 		(void) putbq(q, bp);	/* not done with this message yet */
2896 
2897 	/*
2898 	 * In 5-bit mode, the high order bits are used
2899 	 * to indicate character sizes less than five,
2900 	 * so we need to explicitly mask before transmitting
2901 	 */
2902 	if ((async->async_ttycommon.t_cflag & CSIZE) == CS5) {
2903 		unsigned char *p = xmit_addr;
2904 		int cnt = cc;
2905 
2906 		while (cnt--)
2907 			*p++ &= (unsigned char) 0x1f;
2908 	}
2909 
2910 	/*
2911 	 * Set up this block for pseudo-DMA.
2912 	 */
2913 	mutex_enter(&asy->asy_excl_hi);
2914 	/*
2915 	 * If the transmitter is ready, shove the first
2916 	 * character out.
2917 	 */
2918 	didsome = B_FALSE;
2919 	while (--fifo_len >= 0 && cc > 0) {
2920 		if (!(ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR) &
2921 		    XHRE))
2922 			break;
2923 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
2924 		    *xmit_addr++);
2925 		cc--;
2926 		didsome = B_TRUE;
2927 	}
2928 	async->async_optr = xmit_addr;
2929 	async->async_ocnt = cc;
2930 	if (didsome)
2931 		async->async_flags |= ASYNC_PROGRESS;
2932 	DEBUGCONT2(ASY_DEBUG_BUSY,
2933 		"async%d_nstart: Set ASYNC_BUSY.  async_ocnt=%d\n",
2934 		instance,
2935 		async->async_ocnt);
2936 	async->async_flags |= ASYNC_BUSY;
2937 	mutex_exit(&asy->asy_excl_hi);
2938 }
2939 
2940 /*
2941  * Resume output by poking the transmitter.
2942  */
2943 static void
2944 async_resume(struct asyncline *async)
2945 {
2946 	struct asycom *asy = async->async_common;
2947 #ifdef DEBUG
2948 	int instance;
2949 #endif
2950 
2951 	ASSERT(mutex_owned(&asy->asy_excl_hi));
2952 #ifdef DEBUG
2953 	instance = UNIT(async->async_dev);
2954 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_resume\n", instance);
2955 #endif
2956 
2957 	if (ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR) & XHRE) {
2958 		if (async_flowcontrol_sw_input(asy, FLOW_CHECK, IN_FLOW_NULL))
2959 			return;
2960 		if (async->async_ocnt > 0 &&
2961 		    !(async->async_flags &
2962 		    (ASYNC_HW_OUT_FLW|ASYNC_SW_OUT_FLW|ASYNC_OUT_SUSPEND))) {
2963 			ddi_put8(asy->asy_iohandle,
2964 			    asy->asy_ioaddr + DAT, *async->async_optr++);
2965 			async->async_ocnt--;
2966 			async->async_flags |= ASYNC_PROGRESS;
2967 		}
2968 	}
2969 }
2970 
2971 /*
2972  * Hold the untimed break to last the minimum time.
2973  */
2974 static void
2975 async_hold_utbrk(void *arg)
2976 {
2977 	struct asyncline *async = arg;
2978 	struct asycom *asy = async->async_common;
2979 
2980 	mutex_enter(&asy->asy_excl);
2981 	async->async_flags &= ~ASYNC_HOLD_UTBRK;
2982 	cv_broadcast(&async->async_flags_cv);
2983 	async->async_utbrktid = 0;
2984 	mutex_exit(&asy->asy_excl);
2985 }
2986 
2987 /*
2988  * Resume the untimed break.
2989  */
2990 static void
2991 async_resume_utbrk(struct asyncline *async)
2992 {
2993 	uchar_t	val;
2994 	struct asycom *asy = async->async_common;
2995 	ASSERT(mutex_owned(&asy->asy_excl));
2996 
2997 	/*
2998 	 * Because the wait time is very short,
2999 	 * so we use uninterruptably wait.
3000 	 */
3001 	while (async->async_flags & ASYNC_HOLD_UTBRK) {
3002 		cv_wait(&async->async_flags_cv, &asy->asy_excl);
3003 	}
3004 	mutex_enter(&asy->asy_excl_hi);
3005 	/*
3006 	 * Timed break and untimed break can exist simultaneously,
3007 	 * if ASYNC_BREAK is also set at here, we don't
3008 	 * really clean the HW break.
3009 	 */
3010 	if (!(async->async_flags & ASYNC_BREAK)) {
3011 		val = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LCR);
3012 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + LCR,
3013 		    (val & ~SETBREAK));
3014 	}
3015 	async->async_flags &= ~ASYNC_OUT_SUSPEND;
3016 	cv_broadcast(&async->async_flags_cv);
3017 	if (async->async_ocnt > 0) {
3018 		async_resume(async);
3019 		mutex_exit(&asy->asy_excl_hi);
3020 	} else {
3021 		async->async_flags &= ~ASYNC_BUSY;
3022 		mutex_exit(&asy->asy_excl_hi);
3023 		if (async->async_xmitblk != NULL) {
3024 			freeb(async->async_xmitblk);
3025 			async->async_xmitblk = NULL;
3026 		}
3027 		async_start(async);
3028 	}
3029 }
3030 
3031 /*
3032  * Process an "ioctl" message sent down to us.
3033  * Note that we don't need to get any locks until we are ready to access
3034  * the hardware.  Nothing we access until then is going to be altered
3035  * outside of the STREAMS framework, so we should be safe.
3036  */
3037 int asydelay = 10000;
3038 static void
3039 async_ioctl(struct asyncline *async, queue_t *wq, mblk_t *mp)
3040 {
3041 	struct asycom *asy = async->async_common;
3042 	tty_common_t  *tp = &async->async_ttycommon;
3043 	struct iocblk *iocp;
3044 	unsigned datasize;
3045 	int error = 0;
3046 	uchar_t val;
3047 	mblk_t *datamp;
3048 	unsigned int index;
3049 
3050 #ifdef DEBUG
3051 	int instance = UNIT(async->async_dev);
3052 
3053 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_ioctl\n", instance);
3054 #endif
3055 
3056 	if (tp->t_iocpending != NULL) {
3057 		/*
3058 		 * We were holding an "ioctl" response pending the
3059 		 * availability of an "mblk" to hold data to be passed up;
3060 		 * another "ioctl" came through, which means that "ioctl"
3061 		 * must have timed out or been aborted.
3062 		 */
3063 		freemsg(async->async_ttycommon.t_iocpending);
3064 		async->async_ttycommon.t_iocpending = NULL;
3065 	}
3066 
3067 	iocp = (struct iocblk *)mp->b_rptr;
3068 
3069 	/*
3070 	 * For TIOCMGET and the PPS ioctls, do NOT call ttycommon_ioctl()
3071 	 * because this function frees up the message block (mp->b_cont) that
3072 	 * contains the user location where we pass back the results.
3073 	 *
3074 	 * Similarly, CONSOPENPOLLEDIO needs ioc_count, which ttycommon_ioctl
3075 	 * zaps.  We know that ttycommon_ioctl doesn't know any CONS*
3076 	 * ioctls, so keep the others safe too.
3077 	 */
3078 	DEBUGCONT2(ASY_DEBUG_IOCTL, "async%d_ioctl: %s\n",
3079 		instance,
3080 		iocp->ioc_cmd == TIOCMGET ? "TIOCMGET" :
3081 		iocp->ioc_cmd == TIOCMSET ? "TIOCMSET" :
3082 		iocp->ioc_cmd == TIOCMBIS ? "TIOCMBIS" :
3083 		iocp->ioc_cmd == TIOCMBIC ? "TIOCMBIC" :
3084 					    "other");
3085 	switch (iocp->ioc_cmd) {
3086 	case TIOCMGET:
3087 	case TIOCGPPS:
3088 	case TIOCSPPS:
3089 	case TIOCGPPSEV:
3090 	case CONSOPENPOLLEDIO:
3091 	case CONSCLOSEPOLLEDIO:
3092 	case CONSSETABORTENABLE:
3093 	case CONSGETABORTENABLE:
3094 		error = -1; /* Do Nothing */
3095 		break;
3096 	default:
3097 
3098 		/*
3099 		 * The only way in which "ttycommon_ioctl" can fail is if the
3100 		 * "ioctl" requires a response containing data to be returned
3101 		 * to the user, and no mblk could be allocated for the data.
3102 		 * No such "ioctl" alters our state.  Thus, we always go ahead
3103 		 * and do any state-changes the "ioctl" calls for.  If we
3104 		 * couldn't allocate the data, "ttycommon_ioctl" has stashed
3105 		 * the "ioctl" away safely, so we just call "bufcall" to
3106 		 * request that we be called back when we stand a better
3107 		 * chance of allocating the data.
3108 		 */
3109 		if ((datasize = ttycommon_ioctl(tp, wq, mp, &error)) != 0) {
3110 			if (async->async_wbufcid)
3111 				unbufcall(async->async_wbufcid);
3112 			async->async_wbufcid = bufcall(datasize, BPRI_HI,
3113 			    (void (*)(void *)) async_reioctl,
3114 			    (void *)(intptr_t)async->async_common->asy_unit);
3115 			return;
3116 		}
3117 	}
3118 
3119 	mutex_enter(&asy->asy_excl);
3120 
3121 	if (error == 0) {
3122 		/*
3123 		 * "ttycommon_ioctl" did most of the work; we just use the
3124 		 * data it set up.
3125 		 */
3126 		switch (iocp->ioc_cmd) {
3127 
3128 		case TCSETS:
3129 			mutex_enter(&asy->asy_excl_hi);
3130 			if (asy_baudok(asy))
3131 				asy_program(asy, ASY_NOINIT);
3132 			else
3133 				error = EINVAL;
3134 			mutex_exit(&asy->asy_excl_hi);
3135 			break;
3136 		case TCSETSF:
3137 		case TCSETSW:
3138 		case TCSETA:
3139 		case TCSETAW:
3140 		case TCSETAF:
3141 			mutex_enter(&asy->asy_excl_hi);
3142 			if (!asy_baudok(asy))
3143 				error = EINVAL;
3144 			else {
3145 				if (asy_isbusy(asy))
3146 					asy_waiteot(asy);
3147 				asy_program(asy, ASY_NOINIT);
3148 			}
3149 			mutex_exit(&asy->asy_excl_hi);
3150 			break;
3151 		}
3152 	} else if (error < 0) {
3153 		/*
3154 		 * "ttycommon_ioctl" didn't do anything; we process it here.
3155 		 */
3156 		error = 0;
3157 		switch (iocp->ioc_cmd) {
3158 
3159 		case TIOCGPPS:
3160 			/*
3161 			 * Get PPS on/off.
3162 			 */
3163 			if (mp->b_cont != NULL)
3164 				freemsg(mp->b_cont);
3165 
3166 			mp->b_cont = allocb(sizeof (int), BPRI_HI);
3167 			if (mp->b_cont == NULL) {
3168 				error = ENOMEM;
3169 				break;
3170 			}
3171 			if (asy->asy_flags & ASY_PPS)
3172 				*(int *)mp->b_cont->b_wptr = 1;
3173 			else
3174 				*(int *)mp->b_cont->b_wptr = 0;
3175 			mp->b_cont->b_wptr += sizeof (int);
3176 			mp->b_datap->db_type = M_IOCACK;
3177 			iocp->ioc_count = sizeof (int);
3178 			break;
3179 
3180 		case TIOCSPPS:
3181 			/*
3182 			 * Set PPS on/off.
3183 			 */
3184 			error = miocpullup(mp, sizeof (int));
3185 			if (error != 0)
3186 				break;
3187 
3188 			mutex_enter(&asy->asy_excl_hi);
3189 			if (*(int *)mp->b_cont->b_rptr)
3190 				asy->asy_flags |= ASY_PPS;
3191 			else
3192 				asy->asy_flags &= ~ASY_PPS;
3193 			/* Reset edge sense */
3194 			asy->asy_flags &= ~ASY_PPS_EDGE;
3195 			mutex_exit(&asy->asy_excl_hi);
3196 			mp->b_datap->db_type = M_IOCACK;
3197 			break;
3198 
3199 		case TIOCGPPSEV:
3200 		{
3201 			/*
3202 			 * Get PPS event data.
3203 			 */
3204 			mblk_t *bp;
3205 			void *buf;
3206 #ifdef _SYSCALL32_IMPL
3207 			struct ppsclockev32 p32;
3208 #endif
3209 			struct ppsclockev ppsclockev;
3210 
3211 			if (mp->b_cont != NULL) {
3212 				freemsg(mp->b_cont);
3213 				mp->b_cont = NULL;
3214 			}
3215 
3216 			if ((asy->asy_flags & ASY_PPS) == 0) {
3217 				error = ENXIO;
3218 				break;
3219 			}
3220 
3221 			/* Protect from incomplete asy_ppsev */
3222 			mutex_enter(&asy->asy_excl_hi);
3223 			ppsclockev = asy_ppsev;
3224 			mutex_exit(&asy->asy_excl_hi);
3225 
3226 #ifdef _SYSCALL32_IMPL
3227 			if ((iocp->ioc_flag & IOC_MODELS) != IOC_NATIVE) {
3228 				TIMEVAL_TO_TIMEVAL32(&p32.tv, &ppsclockev.tv);
3229 				p32.serial = ppsclockev.serial;
3230 				buf = &p32;
3231 				iocp->ioc_count = sizeof (struct ppsclockev32);
3232 			} else
3233 #endif
3234 			{
3235 				buf = &ppsclockev;
3236 				iocp->ioc_count = sizeof (struct ppsclockev);
3237 			}
3238 
3239 			if ((bp = allocb(iocp->ioc_count, BPRI_HI)) == NULL) {
3240 				error = ENOMEM;
3241 				break;
3242 			}
3243 			mp->b_cont = bp;
3244 
3245 			bcopy(buf, bp->b_wptr, iocp->ioc_count);
3246 			bp->b_wptr += iocp->ioc_count;
3247 			mp->b_datap->db_type = M_IOCACK;
3248 			break;
3249 		}
3250 
3251 		case TCSBRK:
3252 			error = miocpullup(mp, sizeof (int));
3253 			if (error != 0)
3254 				break;
3255 
3256 			if (*(int *)mp->b_cont->b_rptr == 0) {
3257 
3258 				/*
3259 				 * XXX Arrangements to ensure that a break
3260 				 * isn't in progress should be sufficient.
3261 				 * This ugly delay() is the only thing
3262 				 * that seems to work on the NCR Worldmark.
3263 				 * It should be replaced. Note that an
3264 				 * asy_waiteot() also does not work.
3265 				 */
3266 				if (asydelay)
3267 					delay(drv_usectohz(asydelay));
3268 
3269 				while (async->async_flags & ASYNC_BREAK) {
3270 					cv_wait(&async->async_flags_cv,
3271 					    &asy->asy_excl);
3272 				}
3273 				mutex_enter(&asy->asy_excl_hi);
3274 				/*
3275 				 * We loop until the TSR is empty and then
3276 				 * set the break.  ASYNC_BREAK has been set
3277 				 * to ensure that no characters are
3278 				 * transmitted while the TSR is being
3279 				 * flushed and SOUT is being used for the
3280 				 * break signal.
3281 				 *
3282 				 * The wait period is equal to
3283 				 * clock / (baud * 16) * 16 * 2.
3284 				 */
3285 				index = BAUDINDEX(
3286 					async->async_ttycommon.t_cflag);
3287 				async->async_flags |= ASYNC_BREAK;
3288 				while ((ddi_get8(asy->asy_iohandle,
3289 				    asy->asy_ioaddr + LSR) & XSRE) == 0) {
3290 					mutex_exit(&asy->asy_excl_hi);
3291 					mutex_exit(&asy->asy_excl);
3292 					drv_usecwait(
3293 						32*asyspdtab[index] & 0xfff);
3294 					mutex_enter(&asy->asy_excl);
3295 					mutex_enter(&asy->asy_excl_hi);
3296 				}
3297 				/*
3298 				 * Arrange for "async_restart"
3299 				 * to be called in 1/4 second;
3300 				 * it will turn the break bit off, and call
3301 				 * "async_start" to grab the next message.
3302 				 */
3303 				val = ddi_get8(asy->asy_iohandle,
3304 					asy->asy_ioaddr + LCR);
3305 				ddi_put8(asy->asy_iohandle,
3306 					asy->asy_ioaddr + LCR,
3307 					(val | SETBREAK));
3308 				mutex_exit(&asy->asy_excl_hi);
3309 				(void) timeout(async_restart, (caddr_t)async,
3310 				    drv_usectohz(1000000)/4);
3311 			} else {
3312 				DEBUGCONT1(ASY_DEBUG_OUT,
3313 					"async%d_ioctl: wait for flush.\n",
3314 					instance);
3315 				mutex_enter(&asy->asy_excl_hi);
3316 				asy_waiteot(asy);
3317 				mutex_exit(&asy->asy_excl_hi);
3318 				DEBUGCONT1(ASY_DEBUG_OUT,
3319 					"async%d_ioctl: ldterm satisfied.\n",
3320 					instance);
3321 			}
3322 			break;
3323 
3324 		case TIOCSBRK:
3325 			if (!(async->async_flags & ASYNC_OUT_SUSPEND)) {
3326 				mutex_enter(&asy->asy_excl_hi);
3327 				async->async_flags |= ASYNC_OUT_SUSPEND;
3328 				async->async_flags |= ASYNC_HOLD_UTBRK;
3329 				index = BAUDINDEX(
3330 				    async->async_ttycommon.t_cflag);
3331 				while ((ddi_get8(asy->asy_iohandle,
3332 				    asy->asy_ioaddr + LSR) & XSRE) == 0) {
3333 					mutex_exit(&asy->asy_excl_hi);
3334 					mutex_exit(&asy->asy_excl);
3335 					drv_usecwait(
3336 					    32*asyspdtab[index] & 0xfff);
3337 					mutex_enter(&asy->asy_excl);
3338 					mutex_enter(&asy->asy_excl_hi);
3339 				}
3340 				val = ddi_get8(asy->asy_iohandle,
3341 				    asy->asy_ioaddr + LCR);
3342 				ddi_put8(asy->asy_iohandle,
3343 				    asy->asy_ioaddr + LCR, (val | SETBREAK));
3344 				mutex_exit(&asy->asy_excl_hi);
3345 				/* wait for 100ms to hold BREAK */
3346 				async->async_utbrktid =
3347 				    timeout((void (*)())async_hold_utbrk,
3348 				    (caddr_t)async,
3349 				    drv_usectohz(asy_min_utbrk));
3350 			}
3351 			mioc2ack(mp, NULL, 0, 0);
3352 			break;
3353 
3354 		case TIOCCBRK:
3355 			if (async->async_flags & ASYNC_OUT_SUSPEND)
3356 				async_resume_utbrk(async);
3357 			mioc2ack(mp, NULL, 0, 0);
3358 			break;
3359 
3360 		case TIOCMSET:
3361 		case TIOCMBIS:
3362 		case TIOCMBIC:
3363 			if (iocp->ioc_count != TRANSPARENT) {
3364 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3365 					"non-transparent\n", instance);
3366 
3367 				error = miocpullup(mp, sizeof (int));
3368 				if (error != 0)
3369 					break;
3370 
3371 				mutex_enter(&asy->asy_excl_hi);
3372 				(void) asymctl(asy,
3373 					dmtoasy(*(int *)mp->b_cont->b_rptr),
3374 					iocp->ioc_cmd);
3375 				mutex_exit(&asy->asy_excl_hi);
3376 				iocp->ioc_error = 0;
3377 				mp->b_datap->db_type = M_IOCACK;
3378 			} else {
3379 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3380 					"transparent\n", instance);
3381 				mcopyin(mp, NULL, sizeof (int), NULL);
3382 			}
3383 			break;
3384 
3385 		case TIOCMGET:
3386 			datamp = allocb(sizeof (int), BPRI_MED);
3387 			if (datamp == NULL) {
3388 				error = EAGAIN;
3389 				break;
3390 			}
3391 
3392 			mutex_enter(&asy->asy_excl_hi);
3393 			*(int *)datamp->b_rptr = asymctl(asy, 0, TIOCMGET);
3394 			mutex_exit(&asy->asy_excl_hi);
3395 
3396 			if (iocp->ioc_count == TRANSPARENT) {
3397 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3398 					"transparent\n", instance);
3399 				mcopyout(mp, NULL, sizeof (int), NULL,
3400 					datamp);
3401 			} else {
3402 				DEBUGCONT1(ASY_DEBUG_IOCTL, "async%d_ioctl: "
3403 					"non-transparent\n", instance);
3404 				mioc2ack(mp, datamp, sizeof (int), 0);
3405 			}
3406 			break;
3407 
3408 		case CONSOPENPOLLEDIO:
3409 			error = miocpullup(mp, sizeof (struct cons_polledio *));
3410 			if (error != 0)
3411 				break;
3412 
3413 			*(struct cons_polledio **)mp->b_cont->b_rptr =
3414 				&asy->polledio;
3415 
3416 			mp->b_datap->db_type = M_IOCACK;
3417 			break;
3418 
3419 		case CONSCLOSEPOLLEDIO:
3420 			mp->b_datap->db_type = M_IOCACK;
3421 			iocp->ioc_error = 0;
3422 			iocp->ioc_rval = 0;
3423 			break;
3424 
3425 		case CONSSETABORTENABLE:
3426 			error = secpolicy_console(iocp->ioc_cr);
3427 			if (error != 0)
3428 				break;
3429 
3430 			if (iocp->ioc_count != TRANSPARENT) {
3431 				error = EINVAL;
3432 				break;
3433 			}
3434 
3435 			if (*(intptr_t *)mp->b_cont->b_rptr)
3436 				asy->asy_flags |= ASY_CONSOLE;
3437 			else
3438 				asy->asy_flags &= ~ASY_CONSOLE;
3439 
3440 			mp->b_datap->db_type = M_IOCACK;
3441 			iocp->ioc_error = 0;
3442 			iocp->ioc_rval = 0;
3443 			break;
3444 
3445 		case CONSGETABORTENABLE:
3446 			/*CONSTANTCONDITION*/
3447 			ASSERT(sizeof (boolean_t) <= sizeof (boolean_t *));
3448 			/*
3449 			 * Store the return value right in the payload
3450 			 * we were passed.  Crude.
3451 			 */
3452 			mcopyout(mp, NULL, sizeof (boolean_t), NULL, NULL);
3453 			*(boolean_t *)mp->b_cont->b_rptr =
3454 				(asy->asy_flags & ASY_CONSOLE) != 0;
3455 			break;
3456 
3457 		default:
3458 			/*
3459 			 * If we don't understand it, it's an error.  NAK it.
3460 			 */
3461 			error = EINVAL;
3462 			break;
3463 		}
3464 	}
3465 	if (error != 0) {
3466 		iocp->ioc_error = error;
3467 		mp->b_datap->db_type = M_IOCNAK;
3468 	}
3469 	mutex_exit(&asy->asy_excl);
3470 	qreply(wq, mp);
3471 	DEBUGCONT1(ASY_DEBUG_PROCS, "async%d_ioctl: done\n", instance);
3472 }
3473 
3474 static int
3475 asyrsrv(queue_t *q)
3476 {
3477 	mblk_t *bp;
3478 	struct asyncline *async;
3479 
3480 	async = (struct asyncline *)q->q_ptr;
3481 
3482 	while (canputnext(q) && (bp = getq(q)))
3483 		putnext(q, bp);
3484 	ASYSETSOFT(async->async_common);
3485 	async->async_polltid = 0;
3486 	return (0);
3487 }
3488 
3489 /*
3490  * Put procedure for write queue.
3491  * Respond to M_STOP, M_START, M_IOCTL, and M_FLUSH messages here;
3492  * set the flow control character for M_STOPI and M_STARTI messages;
3493  * queue up M_BREAK, M_DELAY, and M_DATA messages for processing
3494  * by the start routine, and then call the start routine; discard
3495  * everything else.  Note that this driver does not incorporate any
3496  * mechanism to negotiate to handle the canonicalization process.
3497  * It expects that these functions are handled in upper module(s),
3498  * as we do in ldterm.
3499  */
3500 static int
3501 asywput(queue_t *q, mblk_t *mp)
3502 {
3503 	struct asyncline *async;
3504 	struct asycom *asy;
3505 #ifdef DEBUG
3506 	int instance;
3507 #endif
3508 	int error;
3509 
3510 	async = (struct asyncline *)q->q_ptr;
3511 #ifdef DEBUG
3512 	instance = UNIT(async->async_dev);
3513 #endif
3514 	asy = async->async_common;
3515 
3516 	switch (mp->b_datap->db_type) {
3517 
3518 	case M_STOP:
3519 		/*
3520 		 * Since we don't do real DMA, we can just let the
3521 		 * chip coast to a stop after applying the brakes.
3522 		 */
3523 		mutex_enter(&asy->asy_excl);
3524 		async->async_flags |= ASYNC_STOPPED;
3525 		mutex_exit(&asy->asy_excl);
3526 		freemsg(mp);
3527 		break;
3528 
3529 	case M_START:
3530 		mutex_enter(&asy->asy_excl);
3531 		if (async->async_flags & ASYNC_STOPPED) {
3532 			async->async_flags &= ~ASYNC_STOPPED;
3533 			/*
3534 			 * If an output operation is in progress,
3535 			 * resume it.  Otherwise, prod the start
3536 			 * routine.
3537 			 */
3538 			if (async->async_ocnt > 0) {
3539 				mutex_enter(&asy->asy_excl_hi);
3540 				async_resume(async);
3541 				mutex_exit(&asy->asy_excl_hi);
3542 			} else {
3543 				async_start(async);
3544 			}
3545 		}
3546 		mutex_exit(&asy->asy_excl);
3547 		freemsg(mp);
3548 		break;
3549 
3550 	case M_IOCTL:
3551 		switch (((struct iocblk *)mp->b_rptr)->ioc_cmd) {
3552 
3553 		case TCSBRK:
3554 			error = miocpullup(mp, sizeof (int));
3555 			if (error != 0) {
3556 				miocnak(q, mp, 0, error);
3557 				return (0);
3558 			}
3559 
3560 			if (*(int *)mp->b_cont->b_rptr != 0) {
3561 				DEBUGCONT1(ASY_DEBUG_OUT,
3562 					"async%d_ioctl: flush request.\n",
3563 					instance);
3564 				(void) putq(q, mp);
3565 				mutex_enter(&asy->asy_excl);
3566 
3567 				/*
3568 				 * If an TIOCSBRK is in progress,
3569 				 * clean it as TIOCCBRK does,
3570 				 * then kick off output.
3571 				 * If TIOCSBRK is not in progress,
3572 				 * just kick off output.
3573 				 */
3574 				async_resume_utbrk(async);
3575 				mutex_exit(&asy->asy_excl);
3576 				break;
3577 			}
3578 			/*FALLTHROUGH*/
3579 		case TCSETSW:
3580 		case TCSETSF:
3581 		case TCSETAW:
3582 		case TCSETAF:
3583 			/*
3584 			 * The changes do not take effect until all
3585 			 * output queued before them is drained.
3586 			 * Put this message on the queue, so that
3587 			 * "async_start" will see it when it's done
3588 			 * with the output before it.  Poke the
3589 			 * start routine, just in case.
3590 			 */
3591 			(void) putq(q, mp);
3592 			mutex_enter(&asy->asy_excl);
3593 
3594 			/*
3595 			 * If an TIOCSBRK is in progress,
3596 			 * clean it as TIOCCBRK does.
3597 			 * then kick off output.
3598 			 * If TIOCSBRK is not in progress,
3599 			 * just kick off output.
3600 			 */
3601 			async_resume_utbrk(async);
3602 			mutex_exit(&asy->asy_excl);
3603 			break;
3604 
3605 		default:
3606 			/*
3607 			 * Do it now.
3608 			 */
3609 			async_ioctl(async, q, mp);
3610 			break;
3611 		}
3612 		break;
3613 
3614 	case M_FLUSH:
3615 		if (*mp->b_rptr & FLUSHW) {
3616 			mutex_enter(&asy->asy_excl);
3617 
3618 			/*
3619 			 * Abort any output in progress.
3620 			 */
3621 			mutex_enter(&asy->asy_excl_hi);
3622 			if (async->async_flags & ASYNC_BUSY) {
3623 			    DEBUGCONT1(ASY_DEBUG_BUSY, "asy%dwput: "
3624 				    "Clearing async_ocnt, "
3625 				    "leaving ASYNC_BUSY set\n",
3626 				    instance);
3627 				async->async_ocnt = 0;
3628 				async->async_flags &= ~ASYNC_BUSY;
3629 			} /* if */
3630 			mutex_exit(&asy->asy_excl_hi);
3631 
3632 			/* Flush FIFO buffers */
3633 			if (asy->asy_use_fifo == FIFO_ON) {
3634 				asy_reset_fifo(asy, FIFOTXFLSH);
3635 			}
3636 
3637 			/*
3638 			 * Flush our write queue.
3639 			 */
3640 			flushq(q, FLUSHDATA);	/* XXX doesn't flush M_DELAY */
3641 			if (async->async_xmitblk != NULL) {
3642 				freeb(async->async_xmitblk);
3643 				async->async_xmitblk = NULL;
3644 			}
3645 			mutex_exit(&asy->asy_excl);
3646 			*mp->b_rptr &= ~FLUSHW;	/* it has been flushed */
3647 		}
3648 		if (*mp->b_rptr & FLUSHR) {
3649 			/* Flush FIFO buffers */
3650 			if (asy->asy_use_fifo == FIFO_ON) {
3651 				asy_reset_fifo(asy, FIFORXFLSH);
3652 			}
3653 			flushq(RD(q), FLUSHDATA);
3654 			qreply(q, mp);	/* give the read queues a crack at it */
3655 		} else {
3656 			freemsg(mp);
3657 		}
3658 
3659 		/*
3660 		 * We must make sure we process messages that survive the
3661 		 * write-side flush.
3662 		 */
3663 		mutex_enter(&asy->asy_excl);
3664 		async_start(async);
3665 		mutex_exit(&asy->asy_excl);
3666 		break;
3667 
3668 	case M_BREAK:
3669 	case M_DELAY:
3670 	case M_DATA:
3671 		/*
3672 		 * Queue the message up to be transmitted,
3673 		 * and poke the start routine.
3674 		 */
3675 		(void) putq(q, mp);
3676 		mutex_enter(&asy->asy_excl);
3677 		async_start(async);
3678 		mutex_exit(&asy->asy_excl);
3679 		break;
3680 
3681 	case M_STOPI:
3682 		mutex_enter(&asy->asy_excl);
3683 		mutex_enter(&asy->asy_excl_hi);
3684 		if (!(async->async_inflow_source & IN_FLOW_USER)) {
3685 			async_flowcontrol_hw_input(asy, FLOW_STOP,
3686 			    IN_FLOW_USER);
3687 			(void) async_flowcontrol_sw_input(asy, FLOW_STOP,
3688 			    IN_FLOW_USER);
3689 		}
3690 		mutex_exit(&asy->asy_excl_hi);
3691 		mutex_exit(&asy->asy_excl);
3692 		freemsg(mp);
3693 		break;
3694 
3695 	case M_STARTI:
3696 		mutex_enter(&asy->asy_excl);
3697 		mutex_enter(&asy->asy_excl_hi);
3698 		if (async->async_inflow_source & IN_FLOW_USER) {
3699 			async_flowcontrol_hw_input(asy, FLOW_START,
3700 			    IN_FLOW_USER);
3701 			(void) async_flowcontrol_sw_input(asy, FLOW_START,
3702 			    IN_FLOW_USER);
3703 		}
3704 		mutex_exit(&asy->asy_excl_hi);
3705 		mutex_exit(&asy->asy_excl);
3706 		freemsg(mp);
3707 		break;
3708 
3709 	case M_CTL:
3710 		if (MBLKL(mp) >= sizeof (struct iocblk) &&
3711 		    ((struct iocblk *)mp->b_rptr)->ioc_cmd == MC_POSIXQUERY) {
3712 			((struct iocblk *)mp->b_rptr)->ioc_cmd = MC_HAS_POSIX;
3713 			qreply(q, mp);
3714 		} else {
3715 			/*
3716 			 * These MC_SERVICE type messages are used by upper
3717 			 * modules to tell this driver to send input up
3718 			 * immediately, or that it can wait for normal
3719 			 * processing that may or may not be done.  Sun
3720 			 * requires these for the mouse module.
3721 			 * (XXX - for x86?)
3722 			 */
3723 			mutex_enter(&asy->asy_excl);
3724 			switch (*mp->b_rptr) {
3725 
3726 			case MC_SERVICEIMM:
3727 				async->async_flags |= ASYNC_SERVICEIMM;
3728 				break;
3729 
3730 			case MC_SERVICEDEF:
3731 				async->async_flags &= ~ASYNC_SERVICEIMM;
3732 				break;
3733 			}
3734 			mutex_exit(&asy->asy_excl);
3735 			freemsg(mp);
3736 		}
3737 		break;
3738 
3739 	case M_IOCDATA:
3740 		async_iocdata(q, mp);
3741 		break;
3742 
3743 	default:
3744 		freemsg(mp);
3745 		break;
3746 	}
3747 	return (0);
3748 }
3749 
3750 /*
3751  * Retry an "ioctl", now that "bufcall" claims we may be able to allocate
3752  * the buffer we need.
3753  */
3754 static void
3755 async_reioctl(void *unit)
3756 {
3757 	int instance = (uintptr_t)unit;
3758 	struct asyncline *async;
3759 	struct asycom *asy;
3760 	queue_t	*q;
3761 	mblk_t	*mp;
3762 
3763 	asy = ddi_get_soft_state(asy_soft_state, instance);
3764 	ASSERT(asy != NULL);
3765 	async = asy->asy_priv;
3766 
3767 	/*
3768 	 * The bufcall is no longer pending.
3769 	 */
3770 	mutex_enter(&asy->asy_excl);
3771 	async->async_wbufcid = 0;
3772 	if ((q = async->async_ttycommon.t_writeq) == NULL) {
3773 		mutex_exit(&asy->asy_excl);
3774 		return;
3775 	}
3776 	if ((mp = async->async_ttycommon.t_iocpending) != NULL) {
3777 		/* not pending any more */
3778 		async->async_ttycommon.t_iocpending = NULL;
3779 		mutex_exit(&asy->asy_excl);
3780 		async_ioctl(async, q, mp);
3781 	} else
3782 		mutex_exit(&asy->asy_excl);
3783 }
3784 
3785 static void
3786 async_iocdata(queue_t *q, mblk_t *mp)
3787 {
3788 	struct asyncline	*async = (struct asyncline *)q->q_ptr;
3789 	struct asycom		*asy;
3790 	struct iocblk *ip;
3791 	struct copyresp *csp;
3792 #ifdef DEBUG
3793 	int instance = UNIT(async->async_dev);
3794 #endif
3795 
3796 	asy = async->async_common;
3797 	ip = (struct iocblk *)mp->b_rptr;
3798 	csp = (struct copyresp *)mp->b_rptr;
3799 
3800 	if (csp->cp_rval != 0) {
3801 		if (csp->cp_private)
3802 			freemsg(csp->cp_private);
3803 		freemsg(mp);
3804 		return;
3805 	}
3806 
3807 	mutex_enter(&asy->asy_excl);
3808 	DEBUGCONT2(ASY_DEBUG_MODEM, "async%d_iocdata: case %s\n",
3809 		instance,
3810 		csp->cp_cmd == TIOCMGET ? "TIOCMGET" :
3811 		csp->cp_cmd == TIOCMSET ? "TIOCMSET" :
3812 		csp->cp_cmd == TIOCMBIS ? "TIOCMBIS" :
3813 		    "TIOCMBIC");
3814 	switch (csp->cp_cmd) {
3815 
3816 	case TIOCMGET:
3817 		if (mp->b_cont) {
3818 			freemsg(mp->b_cont);
3819 			mp->b_cont = NULL;
3820 		}
3821 		mp->b_datap->db_type = M_IOCACK;
3822 		ip->ioc_error = 0;
3823 		ip->ioc_count = 0;
3824 		ip->ioc_rval = 0;
3825 		mp->b_wptr = mp->b_rptr + sizeof (struct iocblk);
3826 		break;
3827 
3828 	case TIOCMSET:
3829 	case TIOCMBIS:
3830 	case TIOCMBIC:
3831 		mutex_enter(&asy->asy_excl_hi);
3832 		(void) asymctl(asy,
3833 			dmtoasy(*(int *)mp->b_cont->b_rptr),
3834 			csp->cp_cmd);
3835 		mutex_exit(&asy->asy_excl_hi);
3836 		mioc2ack(mp, NULL, 0, 0);
3837 		break;
3838 
3839 	default:
3840 		mp->b_datap->db_type = M_IOCNAK;
3841 		ip->ioc_error = EINVAL;
3842 		break;
3843 	}
3844 	qreply(q, mp);
3845 	mutex_exit(&asy->asy_excl);
3846 }
3847 
3848 /*
3849  * debugger/console support routines.
3850  */
3851 
3852 /*
3853  * put a character out
3854  * Do not use interrupts.  If char is LF, put out CR, LF.
3855  */
3856 static void
3857 asyputchar(struct cons_polledio_arg *arg, uchar_t c)
3858 {
3859 	struct asycom *asy = (struct asycom *)arg;
3860 
3861 	if (c == '\n')
3862 		asyputchar(arg, '\r');
3863 
3864 	while ((ddi_get8(asy->asy_iohandle,
3865 	    asy->asy_ioaddr + LSR) & XHRE) == 0) {
3866 		/* wait for xmit to finish */
3867 		drv_usecwait(10);
3868 	}
3869 
3870 	/* put the character out */
3871 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT, c);
3872 }
3873 
3874 /*
3875  * See if there's a character available. If no character is
3876  * available, return 0. Run in polled mode, no interrupts.
3877  */
3878 static boolean_t
3879 asyischar(struct cons_polledio_arg *arg)
3880 {
3881 	struct asycom *asy = (struct asycom *)arg;
3882 
3883 	return ((ddi_get8(asy->asy_iohandle,
3884 		asy->asy_ioaddr + LSR) & RCA) != 0);
3885 }
3886 
3887 /*
3888  * Get a character. Run in polled mode, no interrupts.
3889  */
3890 static int
3891 asygetchar(struct cons_polledio_arg *arg)
3892 {
3893 	struct asycom *asy = (struct asycom *)arg;
3894 
3895 	while (!asyischar(arg))
3896 		drv_usecwait(10);
3897 	return (ddi_get8(asy->asy_iohandle,
3898 		asy->asy_ioaddr + DAT));
3899 }
3900 
3901 /*
3902  * Set or get the modem control status.
3903  */
3904 static int
3905 asymctl(struct asycom *asy, int bits, int how)
3906 {
3907 	int mcr_r, msr_r;
3908 	int instance = asy->asy_unit;
3909 
3910 	ASSERT(mutex_owned(&asy->asy_excl_hi));
3911 	ASSERT(mutex_owned(&asy->asy_excl));
3912 
3913 	/* Read Modem Control Registers */
3914 	mcr_r = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
3915 
3916 	switch (how) {
3917 
3918 	case TIOCMSET:
3919 		DEBUGCONT2(ASY_DEBUG_MODEM,
3920 			"asy%dmctl: TIOCMSET, bits = %x\n", instance, bits);
3921 		mcr_r = bits;		/* Set bits	*/
3922 		break;
3923 
3924 	case TIOCMBIS:
3925 		DEBUGCONT2(ASY_DEBUG_MODEM, "asy%dmctl: TIOCMBIS, bits = %x\n",
3926 			instance, bits);
3927 		mcr_r |= bits;		/* Mask in bits	*/
3928 		break;
3929 
3930 	case TIOCMBIC:
3931 		DEBUGCONT2(ASY_DEBUG_MODEM, "asy%dmctl: TIOCMBIC, bits = %x\n",
3932 			instance, bits);
3933 		mcr_r &= ~bits;		/* Mask out bits */
3934 		break;
3935 
3936 	case TIOCMGET:
3937 		/* Read Modem Status Registers */
3938 		/*
3939 		 * If modem interrupts are enabled, we return the
3940 		 * saved value of msr. We read MSR only in async_msint()
3941 		 */
3942 		if (ddi_get8(asy->asy_iohandle,
3943 		    asy->asy_ioaddr + ICR) & MIEN) {
3944 			msr_r = asy->asy_msr;
3945 			DEBUGCONT2(ASY_DEBUG_MODEM,
3946 				"asy%dmctl: TIOCMGET, read msr_r = %x\n",
3947 				instance, msr_r);
3948 		} else {
3949 			msr_r = ddi_get8(asy->asy_iohandle,
3950 					asy->asy_ioaddr + MSR);
3951 			DEBUGCONT2(ASY_DEBUG_MODEM,
3952 				"asy%dmctl: TIOCMGET, read MSR = %x\n",
3953 				instance, msr_r);
3954 		}
3955 		DEBUGCONT2(ASY_DEBUG_MODEM, "asy%dtodm: modem_lines = %x\n",
3956 			instance, asytodm(mcr_r, msr_r));
3957 		return (asytodm(mcr_r, msr_r));
3958 	}
3959 
3960 	ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + MCR, mcr_r);
3961 
3962 	return (mcr_r);
3963 }
3964 
3965 static int
3966 asytodm(int mcr_r, int msr_r)
3967 {
3968 	int b = 0;
3969 
3970 	/* MCR registers */
3971 	if (mcr_r & RTS)
3972 		b |= TIOCM_RTS;
3973 
3974 	if (mcr_r & DTR)
3975 		b |= TIOCM_DTR;
3976 
3977 	/* MSR registers */
3978 	if (msr_r & DCD)
3979 		b |= TIOCM_CAR;
3980 
3981 	if (msr_r & CTS)
3982 		b |= TIOCM_CTS;
3983 
3984 	if (msr_r & DSR)
3985 		b |= TIOCM_DSR;
3986 
3987 	if (msr_r & RI)
3988 		b |= TIOCM_RNG;
3989 	return (b);
3990 }
3991 
3992 static int
3993 dmtoasy(int bits)
3994 {
3995 	int b = 0;
3996 
3997 	DEBUGCONT1(ASY_DEBUG_MODEM, "dmtoasy: bits = %x\n", bits);
3998 #ifdef	CAN_NOT_SET	/* only DTR and RTS can be set */
3999 	if (bits & TIOCM_CAR)
4000 		b |= DCD;
4001 	if (bits & TIOCM_CTS)
4002 		b |= CTS;
4003 	if (bits & TIOCM_DSR)
4004 		b |= DSR;
4005 	if (bits & TIOCM_RNG)
4006 		b |= RI;
4007 #endif
4008 
4009 	if (bits & TIOCM_RTS) {
4010 		DEBUGCONT0(ASY_DEBUG_MODEM, "dmtoasy: set b & RTS\n");
4011 		b |= RTS;
4012 	}
4013 	if (bits & TIOCM_DTR) {
4014 		DEBUGCONT0(ASY_DEBUG_MODEM, "dmtoasy: set b & DTR\n");
4015 		b |= DTR;
4016 	}
4017 
4018 	return (b);
4019 }
4020 
4021 static void
4022 asyerror(int level, const char *fmt, ...)
4023 {
4024 	va_list adx;
4025 	static	time_t	last;
4026 	static	const char *lastfmt;
4027 	time_t	now;
4028 
4029 	/*
4030 	 * Don't print the same error message too often.
4031 	 * Print the message only if we have not printed the
4032 	 * message within the last second.
4033 	 * Note: that fmt cannot be a pointer to a string
4034 	 * stored on the stack. The fmt pointer
4035 	 * must be in the data segment otherwise lastfmt would point
4036 	 * to non-sense.
4037 	 */
4038 	now = gethrestime_sec();
4039 	if (last == now && lastfmt == fmt)
4040 		return;
4041 
4042 	last = now;
4043 	lastfmt = fmt;
4044 
4045 	va_start(adx, fmt);
4046 	vcmn_err(level, fmt, adx);
4047 	va_end(adx);
4048 }
4049 
4050 /*
4051  * asy_parse_mode(dev_info_t *devi, struct asycom *asy)
4052  * The value of this property is in the form of "9600,8,n,1,-"
4053  * 1) speed: 9600, 4800, ...
4054  * 2) data bits
4055  * 3) parity: n(none), e(even), o(odd)
4056  * 4) stop bits
4057  * 5) handshake: -(none), h(hardware: rts/cts), s(software: xon/off)
4058  *
4059  * This parsing came from a SPARCstation eeprom.
4060  */
4061 static void
4062 asy_parse_mode(dev_info_t *devi, struct asycom *asy)
4063 {
4064 	char		name[40];
4065 	char		val[40];
4066 	int		len;
4067 	int		ret;
4068 	char		*p;
4069 	char		*p1;
4070 
4071 	ASSERT(asy->asy_com_port != 0);
4072 
4073 	/*
4074 	 * Parse the ttyx-mode property
4075 	 */
4076 	(void) sprintf(name, "tty%c-mode", asy->asy_com_port + 'a' - 1);
4077 	len = sizeof (val);
4078 	ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
4079 	if (ret != DDI_PROP_SUCCESS) {
4080 		(void) sprintf(name, "com%c-mode", asy->asy_com_port + '0');
4081 		len = sizeof (val);
4082 		ret = GET_PROP(devi, name, DDI_PROP_CANSLEEP, val, &len);
4083 	}
4084 
4085 	/* no property to parse */
4086 	asy->asy_cflag = 0;
4087 	if (ret != DDI_PROP_SUCCESS)
4088 		return;
4089 
4090 	p = val;
4091 	/* ---- baud rate ---- */
4092 	asy->asy_cflag = CREAD|B9600;		/* initial default */
4093 	if (p && (p1 = strchr(p, ',')) != 0) {
4094 		*p1++ = '\0';
4095 	} else {
4096 		asy->asy_cflag |= BITS8;	/* add default bits */
4097 		return;
4098 	}
4099 
4100 	if (strcmp(p, "110") == 0)
4101 		asy->asy_bidx = B110;
4102 	else if (strcmp(p, "150") == 0)
4103 		asy->asy_bidx = B150;
4104 	else if (strcmp(p, "300") == 0)
4105 		asy->asy_bidx = B300;
4106 	else if (strcmp(p, "600") == 0)
4107 		asy->asy_bidx = B600;
4108 	else if (strcmp(p, "1200") == 0)
4109 		asy->asy_bidx = B1200;
4110 	else if (strcmp(p, "2400") == 0)
4111 		asy->asy_bidx = B2400;
4112 	else if (strcmp(p, "4800") == 0)
4113 		asy->asy_bidx = B4800;
4114 	else if (strcmp(p, "9600") == 0)
4115 		asy->asy_bidx = B9600;
4116 	else if (strcmp(p, "19200") == 0)
4117 		asy->asy_bidx = B19200;
4118 	else if (strcmp(p, "38400") == 0)
4119 		asy->asy_bidx = B38400;
4120 	else if (strcmp(p, "57600") == 0)
4121 		asy->asy_bidx = B57600;
4122 	else if (strcmp(p, "115200") == 0)
4123 		asy->asy_bidx = B115200;
4124 	else
4125 		asy->asy_bidx = B9600;
4126 
4127 	asy->asy_cflag &= ~CBAUD;
4128 	if (asy->asy_bidx > CBAUD) {	/* > 38400 uses the CBAUDEXT bit */
4129 		asy->asy_cflag |= CBAUDEXT;
4130 		asy->asy_cflag |= asy->asy_bidx - CBAUD - 1;
4131 	} else {
4132 		asy->asy_cflag |= asy->asy_bidx;
4133 	}
4134 
4135 	ASSERT(asy->asy_bidx == BAUDINDEX(asy->asy_cflag));
4136 
4137 	/* ---- Next item is data bits ---- */
4138 	p = p1;
4139 	if (p && (p1 = strchr(p, ',')) != 0)  {
4140 		*p1++ = '\0';
4141 	} else {
4142 		asy->asy_cflag |= BITS8;	/* add default bits */
4143 		return;
4144 	}
4145 	switch (*p) {
4146 		default:
4147 		case '8':
4148 			asy->asy_cflag |= CS8;
4149 			asy->asy_lcr = BITS8;
4150 			break;
4151 		case '7':
4152 			asy->asy_cflag |= CS7;
4153 			asy->asy_lcr = BITS7;
4154 			break;
4155 		case '6':
4156 			asy->asy_cflag |= CS6;
4157 			asy->asy_lcr = BITS6;
4158 			break;
4159 		case '5':
4160 			/* LINTED: CS5 is currently zero (but might change) */
4161 			asy->asy_cflag |= CS5;
4162 			asy->asy_lcr = BITS5;
4163 			break;
4164 	}
4165 
4166 	/* ---- Parity info ---- */
4167 	p = p1;
4168 	if (p && (p1 = strchr(p, ',')) != 0)  {
4169 		*p1++ = '\0';
4170 	} else {
4171 		return;
4172 	}
4173 	switch (*p)  {
4174 		default:
4175 		case 'n':
4176 			break;
4177 		case 'e':
4178 			asy->asy_cflag |= PARENB;
4179 			asy->asy_lcr |= PEN; break;
4180 		case 'o':
4181 			asy->asy_cflag |= PARENB|PARODD;
4182 			asy->asy_lcr |= PEN|EPS;
4183 			break;
4184 	}
4185 
4186 	/* ---- Find stop bits ---- */
4187 	p = p1;
4188 	if (p && (p1 = strchr(p, ',')) != 0)  {
4189 		*p1++ = '\0';
4190 	} else {
4191 		return;
4192 	}
4193 	if (*p == '2') {
4194 		asy->asy_cflag |= CSTOPB;
4195 		asy->asy_lcr |= STB;
4196 	}
4197 
4198 	/* ---- handshake is next ---- */
4199 	p = p1;
4200 	if (p) {
4201 		if ((p1 = strchr(p, ',')) != 0)
4202 			*p1++ = '\0';
4203 
4204 		if (*p == 'h')
4205 			asy->asy_cflag |= CRTSCTS;
4206 		else if (*p == 's')
4207 			asy->asy_cflag |= CRTSXOFF;
4208 	}
4209 }
4210 
4211 /*
4212  * Check for abort character sequence
4213  */
4214 static boolean_t
4215 abort_charseq_recognize(uchar_t ch)
4216 {
4217 	static int state = 0;
4218 #define	CNTRL(c) ((c)&037)
4219 	static char sequence[] = { '\r', '~', CNTRL('b') };
4220 
4221 	if (ch == sequence[state]) {
4222 		if (++state >= sizeof (sequence)) {
4223 			state = 0;
4224 			return (B_TRUE);
4225 		}
4226 	} else {
4227 		state = (ch == sequence[0]) ? 1 : 0;
4228 	}
4229 	return (B_FALSE);
4230 }
4231 
4232 /*
4233  * Flow control functions
4234  */
4235 /*
4236  * Software input flow control
4237  * This function can execute software input flow control sucessfully
4238  * at most of situations except that the line is in BREAK status
4239  * (timed and untimed break).
4240  * INPUT VALUE of onoff:
4241  *               FLOW_START means to send out a XON char
4242  *                          and clear SW input flow control flag.
4243  *               FLOW_STOP means to send out a XOFF char
4244  *                          and set SW input flow control flag.
4245  *               FLOW_CHECK means to check whether there is pending XON/XOFF
4246  *                          if it is true, send it out.
4247  * INPUT VALUE of type:
4248  *		 IN_FLOW_RINGBUFF means flow control is due to RING BUFFER
4249  *		 IN_FLOW_STREAMS means flow control is due to STREAMS
4250  *		 IN_FLOW_USER means flow control is due to user's commands
4251  * RETURN VALUE: B_FALSE means no flow control char is sent
4252  *               B_TRUE means one flow control char is sent
4253  */
4254 static boolean_t
4255 async_flowcontrol_sw_input(struct asycom *asy, async_flowc_action onoff,
4256     int type)
4257 {
4258 	struct asyncline *async = asy->asy_priv;
4259 	int instance = UNIT(async->async_dev);
4260 	int rval = B_FALSE;
4261 
4262 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4263 
4264 	if (!(async->async_ttycommon.t_iflag & IXOFF))
4265 		return (rval);
4266 
4267 	/*
4268 	 * If we get this far, then we know IXOFF is set.
4269 	 */
4270 	switch (onoff) {
4271 	case FLOW_STOP:
4272 		async->async_inflow_source |= type;
4273 
4274 		/*
4275 		 * We'll send an XOFF character for each of up to
4276 		 * three different input flow control attempts to stop input.
4277 		 * If we already send out one XOFF, but FLOW_STOP comes again,
4278 		 * it seems that input flow control becomes more serious,
4279 		 * then send XOFF again.
4280 		 */
4281 		if (async->async_inflow_source & (IN_FLOW_RINGBUFF |
4282 		    IN_FLOW_STREAMS | IN_FLOW_USER))
4283 			async->async_flags |= ASYNC_SW_IN_FLOW |
4284 			    ASYNC_SW_IN_NEEDED;
4285 		DEBUGCONT2(ASY_DEBUG_SFLOW, "async%d: input sflow stop, "
4286 		    "type = %x\n", instance, async->async_inflow_source);
4287 		break;
4288 	case FLOW_START:
4289 		async->async_inflow_source &= ~type;
4290 		if (async->async_inflow_source == 0) {
4291 			async->async_flags = (async->async_flags &
4292 			    ~ASYNC_SW_IN_FLOW) | ASYNC_SW_IN_NEEDED;
4293 			DEBUGCONT1(ASY_DEBUG_SFLOW, "async%d: "
4294 			    "input sflow start\n", instance);
4295 		}
4296 		break;
4297 	default:
4298 		break;
4299 	}
4300 
4301 	if (((async->async_flags & (ASYNC_SW_IN_NEEDED | ASYNC_BREAK |
4302 	    ASYNC_OUT_SUSPEND)) == ASYNC_SW_IN_NEEDED) &&
4303 	    (ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + LSR) & XHRE)) {
4304 		/*
4305 		 * If we get this far, then we know we need to send out
4306 		 * XON or XOFF char.
4307 		 */
4308 		async->async_flags = (async->async_flags &
4309 		    ~ASYNC_SW_IN_NEEDED) | ASYNC_BUSY;
4310 		ddi_put8(asy->asy_iohandle, asy->asy_ioaddr + DAT,
4311 		    async->async_flags & ASYNC_SW_IN_FLOW ?
4312 		    async->async_stopc : async->async_startc);
4313 		rval = B_TRUE;
4314 	}
4315 	return (rval);
4316 }
4317 
4318 /*
4319  * Software output flow control
4320  * This function can be executed sucessfully at any situation.
4321  * It does not handle HW, and just change the SW output flow control flag.
4322  * INPUT VALUE of onoff:
4323  *                 FLOW_START means to clear SW output flow control flag,
4324  *			also combine with HW output flow control status to
4325  *			determine if we need to set ASYNC_OUT_FLW_RESUME.
4326  *                 FLOW_STOP means to set SW output flow control flag,
4327  *			also clear ASYNC_OUT_FLW_RESUME.
4328  */
4329 static void
4330 async_flowcontrol_sw_output(struct asycom *asy, async_flowc_action onoff)
4331 {
4332 	struct asyncline *async = asy->asy_priv;
4333 	int instance = UNIT(async->async_dev);
4334 
4335 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4336 
4337 	if (!(async->async_ttycommon.t_iflag & IXON))
4338 		return;
4339 
4340 	switch (onoff) {
4341 	case FLOW_STOP:
4342 		async->async_flags |= ASYNC_SW_OUT_FLW;
4343 		async->async_flags &= ~ASYNC_OUT_FLW_RESUME;
4344 		DEBUGCONT1(ASY_DEBUG_SFLOW, "async%d: output sflow stop\n",
4345 		    instance);
4346 		break;
4347 	case FLOW_START:
4348 		async->async_flags &= ~ASYNC_SW_OUT_FLW;
4349 		if (!(async->async_flags & ASYNC_HW_OUT_FLW))
4350 			async->async_flags |= ASYNC_OUT_FLW_RESUME;
4351 		DEBUGCONT1(ASY_DEBUG_SFLOW, "async%d: output sflow start\n",
4352 		    instance);
4353 		break;
4354 	default:
4355 		break;
4356 	}
4357 }
4358 
4359 /*
4360  * Hardware input flow control
4361  * This function can be executed sucessfully at any situation.
4362  * It directly changes RTS depending on input parameter onoff.
4363  * INPUT VALUE of onoff:
4364  *       FLOW_START means to clear HW input flow control flag,
4365  *                  and pull up RTS if it is low.
4366  *       FLOW_STOP means to set HW input flow control flag,
4367  *                  and low RTS if it is high.
4368  * INPUT VALUE of type:
4369  *		 IN_FLOW_RINGBUFF means flow control is due to RING BUFFER
4370  *		 IN_FLOW_STREAMS means flow control is due to STREAMS
4371  *		 IN_FLOW_USER means flow control is due to user's commands
4372  */
4373 static void
4374 async_flowcontrol_hw_input(struct asycom *asy, async_flowc_action onoff,
4375     int type)
4376 {
4377 	uchar_t	mcr;
4378 	uchar_t	flag;
4379 	struct asyncline *async = asy->asy_priv;
4380 	int instance = UNIT(async->async_dev);
4381 
4382 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4383 
4384 	if (!(async->async_ttycommon.t_cflag & CRTSXOFF))
4385 		return;
4386 
4387 	switch (onoff) {
4388 	case FLOW_STOP:
4389 		async->async_inflow_source |= type;
4390 		if (async->async_inflow_source & (IN_FLOW_RINGBUFF |
4391 		    IN_FLOW_STREAMS | IN_FLOW_USER))
4392 			async->async_flags |= ASYNC_HW_IN_FLOW;
4393 		DEBUGCONT2(ASY_DEBUG_HFLOW, "async%d: input hflow stop, "
4394 		    "type = %x\n", instance, async->async_inflow_source);
4395 		break;
4396 	case FLOW_START:
4397 		async->async_inflow_source &= ~type;
4398 		if (async->async_inflow_source == 0) {
4399 			async->async_flags &= ~ASYNC_HW_IN_FLOW;
4400 			DEBUGCONT1(ASY_DEBUG_HFLOW, "async%d: "
4401 			    "input hflow start\n", instance);
4402 		}
4403 		break;
4404 	default:
4405 		break;
4406 	}
4407 	mcr = ddi_get8(asy->asy_iohandle, asy->asy_ioaddr + MCR);
4408 	flag = (async->async_flags & ASYNC_HW_IN_FLOW) ? 0 : RTS;
4409 
4410 	if (((mcr ^ flag) & RTS) != 0) {
4411 		ddi_put8(asy->asy_iohandle,
4412 		    asy->asy_ioaddr + MCR, (mcr ^ RTS));
4413 	}
4414 }
4415 
4416 /*
4417  * Hardware output flow control
4418  * This function can execute HW output flow control sucessfully
4419  * at any situation.
4420  * It doesn't really change RTS, and just change
4421  * HW output flow control flag depending on CTS status.
4422  * INPUT VALUE of onoff:
4423  *                FLOW_START means to clear HW output flow control flag.
4424  *			also combine with SW output flow control status to
4425  *			determine if we need to set ASYNC_OUT_FLW_RESUME.
4426  *                FLOW_STOP means to set HW output flow control flag.
4427  *			also clear ASYNC_OUT_FLW_RESUME.
4428  */
4429 static void
4430 async_flowcontrol_hw_output(struct asycom *asy, async_flowc_action onoff)
4431 {
4432 	struct asyncline *async = asy->asy_priv;
4433 	int instance = UNIT(async->async_dev);
4434 
4435 	ASSERT(mutex_owned(&asy->asy_excl_hi));
4436 
4437 	if (!(async->async_ttycommon.t_cflag & CRTSCTS))
4438 		return;
4439 
4440 	switch (onoff) {
4441 	case FLOW_STOP:
4442 		async->async_flags |= ASYNC_HW_OUT_FLW;
4443 		async->async_flags &= ~ASYNC_OUT_FLW_RESUME;
4444 		DEBUGCONT1(ASY_DEBUG_HFLOW, "async%d: output hflow stop\n",
4445 		    instance);
4446 		break;
4447 	case FLOW_START:
4448 		async->async_flags &= ~ASYNC_HW_OUT_FLW;
4449 		if (!(async->async_flags & ASYNC_SW_OUT_FLW))
4450 			async->async_flags |= ASYNC_OUT_FLW_RESUME;
4451 		DEBUGCONT1(ASY_DEBUG_HFLOW, "async%d: output hflow start\n",
4452 		    instance);
4453 		break;
4454 	default:
4455 		break;
4456 	}
4457 }
4458