xref: /titanic_41/usr/src/uts/sun/io/zs_hdlc.c (revision 5bbb4db2c3f208d12bf0fd11769728f9e5ba66a2)
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 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 
27 /*
28  *	HDLC protocol handler for Z8530 SCC.
29  */
30 
31 #include	<sys/param.h>
32 #include	<sys/systm.h>
33 #include	<sys/types.h>
34 #include	<sys/sysmacros.h>
35 #include	<sys/kmem.h>
36 #include	<sys/stropts.h>
37 #include	<sys/stream.h>
38 #include	<sys/strsun.h>
39 #include	<sys/stat.h>
40 #include	<sys/cred.h>
41 #include	<sys/user.h>
42 #include	<sys/proc.h>
43 #include	<sys/file.h>
44 #include	<sys/uio.h>
45 #include	<sys/buf.h>
46 #include	<sys/mkdev.h>
47 #include	<sys/cmn_err.h>
48 #include	<sys/errno.h>
49 #include	<sys/fcntl.h>
50 
51 #include	<sys/zsdev.h>
52 #include	<sys/ser_sync.h>
53 #include	<sys/conf.h>
54 #include	<sys/ddi.h>
55 #include	<sys/sunddi.h>
56 #include	<sys/dlpi.h>
57 
58 #define	ZSH_TRACING
59 #ifdef	ZSH_TRACING
60 #include	<sys/vtrace.h>
61 
62 /*
63  * Temp tracepoint definitions
64  */
65 #define	TR_ZSH		50
66 
67 #define	TR_ZSH_TXINT	1
68 #define	TR_ZSH_XSINT	2
69 #define	TR_ZSH_RXINT	3
70 #define	TR_ZSH_SRINT	4
71 
72 #define	TR_ZSH_WPUT_START		5
73 #define	TR_ZSH_WPUT_END			6
74 #define	TR_ZSH_START_START		7
75 #define	TR_ZSH_START_END		8
76 #define	TR_ZSH_SOFT_START		9
77 #define	TR_ZSH_SOFT_END			10
78 
79 #define	TR_ZSH_OPEN	 11
80 #define	TR_ZSH_CLOSE	12
81 
82 #endif	/* ZSH_TRACING */
83 
84 /*
85  * Logging definitions
86  */
87 
88 /*
89  * #define	ZSH_DEBUG
90  */
91 #ifdef ZSH_DEBUG
92 
93 #ifdef ZS_DEBUG_ALL
94 extern	char	zs_h_log[];
95 extern	int	zs_h_log_n;
96 #define	zsh_h_log_add(c) \
97 	{ \
98 		if (zs_h_log_n >= ZS_H_LOG_MAX) \
99 			zs_h_log_n = 0; \
100 		zs_h_log[zs_h_log_n++] = 'A' + zs->zs_unit; \
101 		zs_h_log[zs_h_log_n++] = c; \
102 		zs_h_log[zs_h_log_n] = '\0'; \
103 	}
104 #define	zsh_h_log_clear
105 #else
106 #define	ZSH_H_LOG_MAX   0x8000
107 char zsh_h_log[2][ZSH_H_LOG_MAX +10];
108 int zsh_h_log_n[2];
109 #define	zsh_h_log_add(c) \
110 	{ \
111 		if (zsh_h_log_n[zs->zs_unit] >= ZSH_H_LOG_MAX) \
112 			zsh_h_log_n[zs->zs_unit] = 0; \
113 		zsh_h_log[zs->zs_unit][zsh_h_log_n[zs->zs_unit]++] = c; \
114 		zsh_h_log[zs->zs_unit][zsh_h_log_n[zs->zs_unit]] = '\0'; \
115 	}
116 
117 #define	zsh_h_log_clear \
118 	{ register char *p; \
119 	for (p = &zsh_h_log[zs->zs_unit][ZSH_H_LOG_MAX]; \
120 		p >= &zsh_h_log[zs->zs_unit][0]; p--) \
121 		*p = '\0'; \
122 	zsh_h_log_n[zs->zs_unit] = 0; \
123 	}
124 #endif
125 
126 #define	ZSH_R0_LOG(r0)  { \
127 	if (r0 & ZSRR0_RX_READY) zsh_h_log_add('R'); \
128 	if (r0 & ZSRR0_TIMER) zsh_h_log_add('Z'); \
129 	if (r0 & ZSRR0_TX_READY) zsh_h_log_add('T'); \
130 	if (r0 & ZSRR0_CD) zsh_h_log_add('D'); \
131 	if (r0 & ZSRR0_SYNC) zsh_h_log_add('S'); \
132 	if (r0 & ZSRR0_CTS) zsh_h_log_add('C'); \
133 	if (r0 & ZSRR0_TXUNDER) zsh_h_log_add('U'); \
134 	if (r0 & ZSRR0_BREAK) zsh_h_log_add('B'); \
135 	}
136 #endif
137 
138 
139 char _depends_on[] = "drv/zs";
140 
141 #ifndef	MAXZSH
142 #define	MAXZSH	2
143 #define	MAXZSHCLONES	(80)	/* three clone opens per instance */
144 #endif	/* MAXZSH */
145 
146 int maxzsh = MAXZSH;
147 
148 int zsh_timer_count = 10;
149 int zsh_default_mru = 1024;
150 
151 struct ser_str *zsh_str = NULL;
152 unsigned char zsh_usedminor[MAXZSHCLONES];
153 
154 
155 /*
156  * The HDLC protocol
157  */
158 int zsh_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result);
159 static int  zsh_probe(dev_info_t *dev);
160 static int  zsh_attach(dev_info_t *dev, ddi_attach_cmd_t cmd);
161 static int  zsh_detach(dev_info_t *dev, ddi_detach_cmd_t cmd);
162 static int  zsh_open(queue_t *rq, dev_t *dev, int flag, int sflag, cred_t *cr);
163 static int  zsh_close(queue_t *rq, int flag);
164 static void zsh_wput(queue_t *wq, mblk_t *mp);
165 static int zsh_start(struct zscom *zs, struct syncline *zss);
166 static void zsh_ioctl(queue_t *wq, mblk_t *mp);
167 
168 static struct module_info hdlc_minfo = {
169 	0x5a48,		/* module ID number: "ZH" */
170 	"zsh",		/* module name */
171 	0,		/* minimum packet size accepted */
172 	INFPSZ,		/* maximum packet size accepted */
173 	12*1024,	/* queue high water mark (bytes) */
174 	4*1024		/* queue low water mark (bytes) */
175 };
176 
177 static struct qinit hdlc_rinit = {
178 	putq,		/* input put procedure */
179 	NULL,		/* input service procedure */
180 	zsh_open,	/* open procedure */
181 	zsh_close,	/* close procedure */
182 	NULL,		/* reserved */
183 	&hdlc_minfo,	/* module info */
184 	NULL		/* reserved */
185 };
186 
187 static struct qinit hdlc_winit = {
188 	(int (*)())zsh_wput,	/* output put procedure */
189 	NULL,		/* output service procedure */
190 	NULL,		/* open procedure */
191 	NULL,		/* close procedure */
192 	NULL,		/* reserved */
193 	&hdlc_minfo,	/* module info */
194 	NULL		/* reserved */
195 };
196 
197 struct streamtab hdlctab = {
198 	&hdlc_rinit,	/* initialize read queue */
199 	&hdlc_winit,	/* initialize write queue */
200 	NULL,		/* mux read qinit */
201 	NULL		/* mux write qinit */
202 };
203 
204 DDI_DEFINE_STREAM_OPS(zsh_ops, nulldev, zsh_probe, zsh_attach,
205     zsh_detach, nodev, zsh_info, D_MP, &hdlctab, ddi_quiesce_not_supported);
206 
207 /*
208  * This is the loadable module wrapper.
209  */
210 
211 #include	<sys/errno.h>
212 #include	<sys/modctl.h>
213 
214 /*
215  * Module linkage information for the kernel.
216  */
217 
218 static struct modldrv modldrv = {
219 	&mod_driverops, /* Type of module.  This one is a driver */
220 	"Z8530 serial HDLC drv",
221 	&zsh_ops,	/* our own ops for this module */
222 };
223 
224 static struct modlinkage modlinkage = {
225 	MODREV_1,
226 	(void *)&modldrv,
227 	NULL
228 };
229 
230 int
231 _init(void)
232 {
233 	return (mod_install(&modlinkage));
234 }
235 
236 int
237 _fini(void)
238 {
239 	return (mod_remove(&modlinkage));
240 }
241 
242 int
243 _info(struct modinfo *modinfop)
244 {
245 	return (mod_info(&modlinkage, modinfop));
246 }
247 
248 
249 /*
250  * The HDLC interrupt entry points.
251  */
252 static void	zsh_txint(struct zscom *zs);
253 static void	zsh_xsint(struct zscom *zs);
254 static void	zsh_rxint(struct zscom *zs);
255 static void	zsh_srint(struct zscom *zs);
256 static int	zsh_softint(struct zscom *zs);
257 
258 struct zsops zsops_hdlc = {
259 	zsh_txint,
260 	zsh_xsint,
261 	zsh_rxint,
262 	zsh_srint,
263 	zsh_softint,
264 	NULL,
265 	NULL
266 };
267 
268 static int	zsh_program(struct zscom *zs, struct scc_mode *sm);
269 static void	zsh_setmstat(struct zscom *zs, int event);
270 static void	zsh_rxbad(struct zscom *zs, struct syncline *zss);
271 static void	zsh_txbad(struct zscom *zs, struct syncline *zss);
272 static void	zsh_watchdog(void *);
273 static void	zsh_callback(void *);
274 static int	zsh_hdp_ok_or_rts_state(struct zscom *zs, struct syncline *zss);
275 static void	zsh_init_port(struct zscom *zs, struct syncline *zss);
276 static int	zsh_setmode(struct zscom *zs, struct syncline *zss,
277 			struct scc_mode *sm);
278 
279 
280 /*
281  * The HDLC Driver.
282  */
283 
284 
285 /*
286  * Special macros to handle STREAMS operations.
287  * These are required to address memory leakage problems.
288  * WARNING : the macro do NOT call ZSSETSOFT
289  */
290 
291 /*
292  * Should be called holding only the adaptive (zs_excl) mutex.
293  */
294 #define	ZSH_GETBLOCK(zs, allocbcount) \
295 { \
296 	register int n = ZSH_MAX_RSTANDBY; \
297 	while (--n >= 0) { \
298 	    if (!zss->sl_rstandby[n]) { \
299 		if ((zss->sl_rstandby[n] = \
300 		    allocb(zss->sl_mru, BPRI_MED)) == NULL) { \
301 		    if (zss->sl_bufcid == 0) { \
302 			mutex_enter(zs->zs_excl_hi); \
303 			if (zss->sl_txstate != TX_OFF) { \
304 			    mutex_exit(zs->zs_excl_hi); \
305 			    zss->sl_bufcid = bufcall(zss->sl_mru, \
306 				    BPRI_MED, zsh_callback, zs); \
307 			    break; \
308 			} else \
309 				mutex_exit(zs->zs_excl_hi); \
310 		    } \
311 		} \
312 		allocbcount--; \
313 	    } \
314 	} \
315 }
316 
317 /*
318  * Should be called holding the spin (zs_excl_hi) mutex.
319  */
320 #define	ZSH_ALLOCB(mp) \
321 { \
322 	register int n = ZSH_MAX_RSTANDBY; \
323 	mp = NULL; \
324 	while (--n >= 0)  { \
325 		if ((mp = zss->sl_rstandby[n]) != NULL) { \
326 			zss->sl_rstandby[n] = NULL; \
327 			break; \
328 		} \
329 	} \
330 }
331 
332 #define	ZSH_PUTQ(mp) \
333 { \
334 	register int wptr, rptr;  \
335 	wptr = zss->sl_rdone_wptr; \
336 	rptr = zss->sl_rdone_rptr; \
337 	zss->sl_rdone[wptr] = mp; \
338 	if ((wptr) + 1 == ZSH_RDONE_MAX) \
339 		zss->sl_rdone_wptr = wptr = 0; \
340 	else \
341 		zss->sl_rdone_wptr = ++wptr; \
342 	if (wptr == rptr) {  /* Should never occur */ \
343 		SCC_BIC(1, ZSWR1_INIT); \
344 		zss->sl_m_error = ENOSR; \
345 		ZSSETSOFT(zs); \
346 	} \
347 }
348 
349 #define	ZSH_FREEMSG(mp) \
350 { \
351 	ZSH_PUTQ(mp); \
352 }
353 
354 
355 /*
356  * Should be called holding only the adaptive (zs_excl) mutex.
357  */
358 #define	ZSH_GETQ(mp) \
359 { \
360 	if (zss->sl_rdone_rptr != zss->sl_rdone_wptr) { \
361 		mp = zss->sl_rdone[zss->sl_rdone_rptr++]; \
362 		if (zss->sl_rdone_rptr == ZSH_RDONE_MAX) \
363 				zss->sl_rdone_rptr = 0; \
364 	} else \
365 		mp = NULL; \
366 }
367 
368 #define	ZSH_FLUSHQ \
369 { \
370 	register mblk_t *tmp; \
371 	for (;;) { \
372 		ZSH_GETQ(tmp); \
373 		if (!(tmp)) \
374 			break; \
375 		freemsg(tmp); \
376 	} \
377 }
378 
379 /*ARGSUSED*/
380 static int
381 zsh_probe(dev_info_t *dev)
382 {
383 	return (DDI_PROBE_DONTCARE);
384 }
385 
386 /*ARGSUSED*/
387 static int
388 zsh_attach(dev_info_t *dev, ddi_attach_cmd_t cmd)
389 {
390 	register int	unit;
391 	char		name[3] = {
392 		'\0', '\0', '\0' 	};
393 
394 	/*
395 	 * Since zsh is a child of the "pseudo" nexus, we can expect the
396 	 * attach routine to be called only once.  We need to create all
397 	 * necessary devices in one shot.  There is never more than one
398 	 * SCC chip that supports zsh devices.
399 	 */
400 
401 	if (cmd != DDI_ATTACH)
402 		return (DDI_FAILURE);
403 	if (zscom == NULL)
404 		return (DDI_FAILURE);	/* zsattach not done */
405 	unit = 2 * ddi_get_instance(dev);
406 	if (unit > 1)
407 		return (DDI_FAILURE);	/* only use cpu ports */
408 
409 	if (ddi_create_minor_node(dev, "zsh", S_IFCHR,
410 	    NULL, DDI_PSEUDO, CLONE_DEV) == DDI_FAILURE) {
411 		ddi_remove_minor_node(dev, NULL);
412 		cmn_err(CE_WARN, "zsh clone device creation failed.");
413 		return (DDI_FAILURE);
414 	}
415 
416 	for (; unit < maxzsh/2; unit++) {
417 		zscom[unit].zs_hdlc_dip = dev;
418 
419 		(void) sprintf(name, "%d", unit);
420 		if (ddi_create_minor_node(dev, name, S_IFCHR,
421 		    2*unit, DDI_PSEUDO, NULL) == DDI_FAILURE) {
422 			ddi_remove_minor_node(dev, NULL);
423 			return (DDI_FAILURE);
424 		}
425 		unit++;
426 		(void) sprintf(name, "%d", unit);
427 		if (ddi_create_minor_node(dev, name, S_IFCHR,
428 		    2*(unit-1)+1, DDI_PSEUDO, NULL) == DDI_FAILURE) {
429 			ddi_remove_minor_node(dev, NULL);
430 			return (DDI_FAILURE);
431 		}
432 	}
433 
434 	return (DDI_SUCCESS);
435 }
436 
437 /* ARGSUSED */
438 int
439 zsh_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg,
440 void **result)
441 {
442 	register dev_t dev = (dev_t)arg;
443 	register int unit, error;
444 	register struct zscom *zs;
445 
446 	if ((unit = UNIT(dev)) >= nzs)
447 		return (DDI_FAILURE);
448 
449 	switch (infocmd) {
450 	case DDI_INFO_DEVT2DEVINFO:
451 		if (zscom == NULL) {
452 			error = DDI_FAILURE;
453 		} else {
454 			zs = &zscom[unit];
455 			*result = zs->zs_hdlc_dip;
456 			error = DDI_SUCCESS;
457 		}
458 		break;
459 	case DDI_INFO_DEVT2INSTANCE:
460 		*result = (void *)(uintptr_t)(unit / 2);
461 		error = DDI_SUCCESS;
462 		break;
463 	default:
464 		error = DDI_FAILURE;
465 	}
466 	return (error);
467 }
468 
469 static int
470 zsh_detach(dev_info_t *dev, ddi_detach_cmd_t cmd)
471 {
472 	if (cmd != DDI_DETACH)
473 		return (DDI_FAILURE);
474 
475 	ddi_remove_minor_node(dev, NULL);
476 
477 	return (DDI_SUCCESS);
478 }
479 
480 static void
481 zsh_init_port(struct zscom *zs, struct syncline *zss)
482 {
483 	register uchar_t s0;
484 
485 	SCC_WRITE(3, (ZSWR3_RX_ENABLE | ZSWR3_RXCRC_ENABLE | ZSWR3_RX_8));
486 	SCC_WRITE(5, (ZSWR5_TX_8 | ZSWR5_DTR | ZSWR5_TXCRC_ENABLE));
487 	zss->sl_rr0 = SCC_READ0();
488 	if (zss->sl_flags & SF_FDXPTP) {
489 		SCC_BIS(5, ZSWR5_TX_ENABLE);
490 		SCC_BIS(5, ZSWR5_RTS);
491 		s0 = SCC_READ0();
492 		if ((s0 & ZSRR0_CTS) ||
493 		    !(zss->sl_mode.sm_config & (CONN_SIGNAL | CONN_IBM))) {
494 			/*
495 			 * send msg that CTS is up
496 			 */
497 			zss->sl_rr0 |= ZSRR0_CTS;
498 			zss->sl_txstate = TX_IDLE;
499 		} else {
500 			zss->sl_flags |= SF_XMT_INPROG;
501 			zss->sl_txstate = TX_RTS;
502 			zss->sl_rr0 &= ~ZSRR0_CTS;
503 			zss->sl_wd_count = zsh_timer_count;
504 			if (!zss->sl_wd_id)
505 				zss->sl_wd_id = timeout(zsh_watchdog,
506 				    zs, SIO_WATCHDOG_TICK);
507 		}
508 	} else {
509 		SCC_BIC(15, ZSR15_CTS);
510 		SCC_BIC(5, ZSWR5_TX_ENABLE);
511 		SCC_BIC(5, ZSWR5_RTS);
512 		zss->sl_flags &= ~SF_FLUSH_WQ;
513 	}
514 }
515 
516 /*
517  * Open routine.
518  */
519 
520 /*ARGSUSED*/
521 static int
522 zsh_open(queue_t *rq, dev_t *dev, int flag, int sflag, cred_t *cr)
523 {
524 	register struct zscom *zs;
525 	register struct syncline *zss;
526 	register struct ser_str *stp;
527 	register int	unit;
528 	register int 	tmp;
529 
530 	if (sflag != CLONEOPEN) {
531 		if (rq->q_ptr)
532 			return (EBUSY);  /* We got a stream that is in use */
533 
534 		unit = UNIT(*dev);
535 		if (unit >= maxzsh)
536 			return (ENXIO);  /* unit not configured */
537 
538 		if (zscom == NULL)
539 			return (ENXIO);  /* device not found by autoconfig */
540 		zs = &zscom[unit];
541 
542 		if (zs->zs_ops == NULL) {
543 			return (ENXIO);  /* device not found by autoconfig */
544 		}
545 
546 		TRACE_1(TR_ZSH, TR_ZSH_OPEN, "zsh_open:unit = %d", unit);
547 
548 		mutex_enter(zs->zs_excl);
549 		if ((zs->zs_ops != &zsops_null) &&
550 		    (zs->zs_ops != &zsops_hdlc)) {
551 			mutex_exit(zs->zs_excl);
552 			return (EBUSY);	 /* another protocol got here first */
553 		}
554 
555 		/* Mark device as busy (for power management) */
556 		(void) pm_busy_component(zs->zs_dip, unit%2+1);
557 		(void) ddi_dev_is_needed(zs->zs_dip, unit%2+1, 1);
558 
559 		zsopinit(zs, &zsops_hdlc);
560 
561 		zss = (struct syncline *)&zscom[unit].zs_priv_str;
562 		stp = &zss->sl_stream;
563 		stp->str_state = NULL;
564 		stp->str_com = (caddr_t)zs;
565 
566 		zss->sl_xhead = NULL;
567 		zss->sl_xactb = NULL;
568 		zs->zs_wr_cur = NULL;
569 		zs->zs_wr_lim = NULL;
570 		zs->zs_wr_cur = NULL;
571 		zs->zs_wr_lim = NULL;
572 		zss->sl_rhead = NULL;
573 		zss->sl_ractb = NULL;
574 		zs->zs_rd_cur = NULL;
575 		zs->zs_rd_lim = NULL;
576 		zss->sl_mstat = NULL;
577 		zss->sl_xstandby = NULL;
578 		zss->sl_wd_id = 0;
579 		zss->sl_soft_active = 0;
580 		zss->sl_stream.str_rq = NULL;
581 
582 		zs->zs_priv = (caddr_t)zss;
583 
584 		zss->sl_mru = zsh_default_mru;
585 		tmp = ZSH_MAX_RSTANDBY;
586 		ZSH_GETBLOCK(zs, tmp);
587 		if (zss->sl_rstandby[0] == NULL) {
588 			cmn_err(CE_WARN, "zsh_open: can't alloc message block");
589 			mutex_exit(zs->zs_excl);
590 			return (ENOSR);
591 		}
592 		mutex_enter(zs->zs_excl_hi);
593 		ZSH_ALLOCB(zss->sl_ractb);
594 		zss->sl_txstate = TX_OFF;
595 		zss->sl_rr0 = SCC_READ0();
596 		zss->sl_flags &= (SF_INITIALIZED | SF_FDXPTP);
597 		if (zss->sl_flags & SF_INITIALIZED)
598 			zsh_init_port(zs, zss);
599 		mutex_exit(zs->zs_excl_hi);
600 		mutex_exit(zs->zs_excl);
601 	} else {   /* CLONEOPEN */
602 		mutex_enter(&zs_curr_lock);
603 		for (unit = maxzsh; unit < MAXZSHCLONES; unit++)
604 			if (!zsh_usedminor[unit]) {
605 				zsh_usedminor[unit] = (unsigned char)unit;
606 				break;
607 			}
608 		mutex_exit(&zs_curr_lock);
609 		if (unit >= MAXZSHCLONES)	/* no slots available */
610 			return (ENODEV);
611 		*dev = makedevice(getmajor(*dev), unit);
612 
613 		stp = kmem_zalloc(sizeof (struct ser_str), KM_NOSLEEP);
614 		if (stp == NULL) {
615 			cmn_err(CE_WARN,
616 			    "zsh clone open failed, no memory, rq=%p\n",
617 			    (void *)rq);
618 			return (ENOMEM);
619 		}
620 		stp->str_state = STR_CLONE;
621 		stp->str_com = NULL;	/* can't determine without ppa */
622 	}
623 	stp->str_rq = rq;
624 	stp->str_inst = unit;
625 
626 	rq->q_ptr = WR(rq)->q_ptr = (caddr_t)stp;
627 	qprocson(rq);
628 	return (0);
629 }
630 
631 /*
632  * Close routine.
633  */
634 int zsh_tx_enable_in_close = 0;
635 
636 /*ARGSUSED*/
637 static int
638 zsh_close(queue_t *rq, int flag)
639 {
640 	struct ser_str *stp;
641 	struct zscom *zs;
642 	struct syncline *zss;
643 	mblk_t	*mp;
644 	int i;
645 	timeout_id_t sl_wd_id;
646 	bufcall_id_t sl_bufcid;
647 
648 	/*
649 	 * Note that a close is only called on the last close of a
650 	 * particular stream.  Assume that we need to do it all.
651 	 */
652 	qprocsoff(rq);				/* no new business after this */
653 
654 	stp = (struct ser_str *)rq->q_ptr;
655 	if (stp == NULL)
656 		return (0);			/* already been closed once */
657 
658 	if (stp->str_state == STR_CLONE) {
659 		zsh_usedminor[stp->str_inst] = 0;
660 	} else {
661 		zs = (struct zscom *)stp->str_com;
662 		if (zs == NULL)
663 			goto out;
664 
665 		TRACE_1(TR_ZSH, TR_ZSH_CLOSE, "zs = %p", zs);
666 
667 		zss = (struct syncline *)zs->zs_priv;
668 		mutex_enter(zs->zs_excl);
669 		flushq(WR(rq), FLUSHALL);
670 		mutex_enter(zs->zs_excl_hi);
671 		if (zss->sl_xstandby) {
672 			zss->sl_xstandby->b_wptr = zss->sl_xstandby->b_rptr;
673 			ZSH_FREEMSG(zss->sl_xstandby);
674 			zss->sl_xstandby = NULL;
675 		}
676 		mutex_exit(zs->zs_excl_hi);
677 
678 		ZSH_FLUSHQ;
679 
680 		/*
681 		 * Stop the Watchdog Timer.
682 		 */
683 		if ((sl_wd_id = zss->sl_wd_id) != 0)
684 			zss->sl_wd_id = 0;
685 
686 		/*
687 		 * Cancel outstanding "bufcall" request.
688 		 */
689 		if ((sl_bufcid = zss->sl_bufcid) != 0)
690 			zss->sl_bufcid = 0;
691 
692 		mutex_enter(zs->zs_excl_hi);
693 		if (zs->zs_wr_cur) {
694 			zs->zs_wr_cur = NULL;
695 			zs->zs_wr_lim = NULL;
696 			SCC_WRITE0(ZSWR0_SEND_ABORT);
697 			ZSDELAY();
698 			ZSDELAY();
699 		}
700 		zss->sl_txstate = TX_OFF;	/* so it can't rearm in close */
701 
702 		zs->zs_wr_cur = NULL;
703 		zs->zs_wr_lim = NULL;
704 		SCC_BIC(15,
705 		    (ZSR15_TX_UNDER | ZSR15_BREAK | ZSR15_SYNC | ZSR15_CTS));
706 		SCC_WRITE(3, 0);		/* Quiesce receiver */
707 		if (zsh_tx_enable_in_close && !(zss->sl_flags & SF_FDXPTP)) {
708 			SCC_BIS(5, ZSWR5_TX_ENABLE);
709 		} else
710 			SCC_BIC(5, ZSWR5_TX_ENABLE);
711 
712 		SCC_BIC(5,  (ZSWR5_DTR | ZSWR5_RTS | ZSWR5_TXCRC_ENABLE));
713 		SCC_WRITE0(ZSWR0_RESET_TXINT);		/* reset TX */
714 		SCC_WRITE0(ZSWR0_RESET_STATUS);		/* reset XS */
715 		SCC_WRITE0(ZSWR0_RESET_ERRORS);
716 		(void) SCC_READDATA();			/* reset RX */
717 		ZSDELAY();
718 		(void) SCC_READDATA();
719 		ZSDELAY();
720 		(void) SCC_READDATA();
721 		ZSDELAY();
722 
723 
724 		/*
725 		 * Free up everything we ever allocated.
726 		 */
727 		if ((mp = zss->sl_rhead) != NULL) {
728 			zss->sl_ractb = NULL;	/* already freed */
729 			zs->zs_rd_cur = NULL;
730 			zs->zs_rd_lim = NULL;
731 			zss->sl_rhead = NULL;
732 		}
733 		mutex_exit(zs->zs_excl_hi);
734 		if (mp)
735 			freemsg(mp);
736 
737 		mutex_enter(zs->zs_excl_hi);
738 		if ((mp = zss->sl_ractb) != NULL) {
739 			zs->zs_rd_cur = NULL;
740 			zs->zs_rd_lim = NULL;
741 			zss->sl_ractb = NULL;
742 		}
743 		mutex_exit(zs->zs_excl_hi);
744 		if (mp)
745 			freemsg(mp);
746 
747 		for (i = 0; i < ZSH_MAX_RSTANDBY; i++) {
748 			mutex_enter(zs->zs_excl_hi);
749 			mp = zss->sl_rstandby[i];
750 			zss->sl_rstandby[i] = NULL;
751 			mutex_exit(zs->zs_excl_hi);
752 			if (mp)
753 				freemsg(mp);
754 		}
755 
756 		mutex_enter(zs->zs_excl_hi);
757 		if ((mp = zss->sl_xhead) != NULL) {
758 			zss->sl_xhead = NULL;
759 			zss->sl_xactb = NULL;
760 		}
761 		mutex_exit(zs->zs_excl_hi);
762 		if (mp)
763 			freemsg(mp);
764 
765 		ZSH_FLUSHQ;
766 
767 		mutex_enter(zs->zs_excl_hi);
768 		if ((mp = zss->sl_xstandby) != NULL)
769 			zss->sl_xstandby = NULL;
770 		mutex_exit(zs->zs_excl_hi);
771 		if (mp)
772 			freemsg(mp);
773 
774 		mutex_enter(zs->zs_excl_hi);
775 		if ((mp = zss->sl_mstat) != NULL)
776 			zss->sl_mstat = NULL;
777 		zss->sl_txstate = TX_OFF;	/* so it can't rearm in close */
778 		mutex_exit(zs->zs_excl_hi);
779 		if (mp)
780 			freemsg(mp);
781 
782 		zss->sl_stream.str_rq = NULL;
783 		zsopinit(zs, &zsops_null);
784 		mutex_exit(zs->zs_excl);
785 		if (sl_wd_id)
786 			(void) untimeout(sl_wd_id);
787 		if (sl_bufcid)
788 			unbufcall(sl_bufcid);
789 		while (zss->sl_soft_active)
790 			drv_usecwait(1);
791 
792 		/* Mark device as available for power management */
793 		(void) pm_idle_component(zs->zs_dip, zs->zs_unit%2+1);
794 	}
795 
796 	if (stp->str_state == STR_CLONE)
797 		kmem_free(stp, sizeof (struct ser_str));
798 
799 out:
800 	rq->q_ptr = WR(rq)->q_ptr = NULL;
801 
802 	return (0);
803 }
804 
805 static int
806 zsh_hdp_ok_or_rts_state(struct zscom *zs, struct syncline *zss)
807 {
808 	register uchar_t s0;
809 
810 	SCC_BIS(15, ZSR15_CTS);
811 	SCC_BIS(5, ZSWR5_RTS);
812 	s0 = SCC_READ0();
813 	if (s0 & ZSRR0_CTS) {
814 		SCC_BIS(5, ZSWR5_TX_ENABLE);
815 		zss->sl_rr0 |= ZSRR0_CTS;
816 		return (1);
817 	}
818 	zss->sl_flags |= SF_XMT_INPROG;
819 	zss->sl_txstate = TX_RTS;
820 	zss->sl_rr0 &= ~ZSRR0_CTS;
821 	zss->sl_wd_count = zsh_timer_count;
822 	return (0);
823 }
824 
825 /*
826  * Put procedure for write queue.
827  */
828 static void
829 zsh_wput(queue_t *wq, mblk_t *mp)
830 {
831 	register struct ser_str *stp = (struct ser_str *)wq->q_ptr;
832 	register struct zscom *zs;
833 	register struct syncline *zss = NULL;
834 	register ulong_t prim, error = 0;
835 	register union DL_primitives *dlp;
836 	register int	ppa;
837 	register mblk_t *tmp;
838 	register struct copyresp	*resp;
839 
840 	/*
841 	 * stp->str_com supplied by open or DLPI attach.
842 	 */
843 	if (stp == NULL) {
844 		freemsg(mp);
845 		return;
846 	}
847 	zs = (struct zscom *)stp->str_com;
848 
849 	TRACE_0(TR_ZSH, TR_ZSH_WPUT_START, "zsh_wput start");
850 
851 	if ((mp->b_datap->db_type == M_FLUSH) &&
852 	    (stp->str_state == STR_CLONE)) {
853 		if (*mp->b_rptr & FLUSHW) {
854 			flushq(wq, FLUSHDATA);
855 			*mp->b_rptr &= ~FLUSHW;
856 		}
857 		if (*mp->b_rptr & FLUSHR)
858 			qreply(wq, mp);  /* let the read queues have at it */
859 		else
860 			freemsg(mp);
861 		return;
862 	}
863 
864 	if ((zs == NULL) && (mp->b_datap->db_type != M_PROTO)) {
865 		freemsg(mp);
866 		cmn_err(CE_WARN,
867 		    "zsh: clone device %d must be attached before use!",
868 		    stp->str_inst);
869 		(void) putnextctl1(RD(wq), M_ERROR, EPROTO);
870 		return;
871 	}
872 
873 	if (stp->str_state == STR_CLONE) {	/* Clone opened, limited. */
874 		if ((mp->b_datap->db_type != M_PROTO) &&
875 		    (mp->b_datap->db_type != M_IOCTL) &&
876 		    (mp->b_datap->db_type != M_IOCDATA)) {
877 			freemsg(mp);
878 			cmn_err(CE_WARN,
879 			    "zsh%x: invalid operation for clone dev.\n",
880 			    stp->str_inst);
881 			(void) putnextctl1(RD(wq), M_ERROR, EPROTO);
882 			return;
883 		}
884 	} else {
885 		zss = (struct syncline *)zs->zs_priv;
886 	}
887 
888 	switch (mp->b_datap->db_type) {
889 
890 	case M_DATA:
891 		/*
892 		 * Queue the message up to be transmitted.
893 		 * Set "in progress" flag and call the start routine.
894 		 */
895 		mutex_enter(zs->zs_excl_hi);
896 		if (!(zss->sl_flags & SF_INITIALIZED)) {
897 			mutex_exit(zs->zs_excl_hi);
898 			cmn_err(CE_WARN,
899 			    "zsh%x not initialized, can't send message",
900 			    zs->zs_unit);
901 			freemsg(mp);
902 			(void) putnextctl1(RD(wq), M_ERROR, ECOMM);
903 			return;
904 		}
905 		mutex_exit(zs->zs_excl_hi);
906 		if (zs->zs_flags & ZS_NEEDSOFT) {
907 			zs->zs_flags &= ~ZS_NEEDSOFT;
908 			(void) zsh_softint(zs);
909 		}
910 		while (mp->b_wptr == mp->b_rptr) {
911 			register mblk_t *mp1;
912 			mp1 = unlinkb(mp);
913 			freemsg(mp);
914 			mp = mp1;
915 			if (mp == NULL)
916 				return;
917 		}
918 		mutex_enter(zs->zs_excl);
919 		(void) putq(wq, mp);
920 		mutex_enter(zs->zs_excl_hi);
921 		if (zss->sl_flags & SF_FLUSH_WQ) {
922 			mutex_exit(zs->zs_excl_hi);
923 			flushq(wq, FLUSHDATA);
924 			mutex_exit(zs->zs_excl);
925 
926 			TRACE_1(TR_ZSH, TR_ZSH_WPUT_END,
927 			    "zsh_wput end: zs = %p", zs);
928 
929 			return;
930 		}
931 		tmp = NULL;
932 again:
933 		if (!zss->sl_xstandby) {
934 			if (tmp)
935 				zss->sl_xstandby = tmp;
936 			else {
937 				mutex_exit(zs->zs_excl_hi);
938 				tmp = getq(wq);
939 				mutex_enter(zs->zs_excl_hi);
940 				if (tmp)
941 					goto again;
942 			}
943 		} else if (tmp) {
944 			mutex_exit(zs->zs_excl_hi);
945 			(void) putbq(wq, tmp);
946 			mutex_enter(zs->zs_excl_hi);
947 		}
948 
949 		if (zss->sl_flags & SF_XMT_INPROG) {
950 			mutex_exit(zs->zs_excl_hi);
951 			mutex_exit(zs->zs_excl);
952 
953 			TRACE_1(TR_ZSH, TR_ZSH_WPUT_END,
954 			    "zsh_wput end: zs = %p", zs);
955 
956 			return;
957 		}
958 
959 		if (!zss->sl_wd_id) {
960 			zss->sl_wd_count = zsh_timer_count;
961 			zss->sl_txstate = TX_IDLE;
962 			mutex_exit(zs->zs_excl_hi);
963 			zss->sl_wd_id = timeout(zsh_watchdog, zs,
964 			    SIO_WATCHDOG_TICK);
965 			mutex_enter(zs->zs_excl_hi);
966 		}
967 
968 		zss->sl_flags |= SF_XMT_INPROG;
969 		if ((zss->sl_flags & SF_FDXPTP) ||
970 		    zsh_hdp_ok_or_rts_state(zs, zss))
971 			(void) zsh_start(zs, zss);
972 		mutex_exit(zs->zs_excl_hi);
973 		mutex_exit(zs->zs_excl);
974 		break;
975 
976 	case M_PROTO:
977 		/*
978 		 * Here is where a clone device finds out about the
979 		 * hardware it is going to attach to.  The request is
980 		 * validated and a ppa is extracted from it and validated.
981 		 * This number is used to index the hardware data structure
982 		 * and the protocol data structure, in case the latter
983 		 * was not provided by a data-path open before this.
984 		 */
985 		if (stp->str_state != STR_CLONE) {
986 			freemsg(mp);
987 			return;
988 		}
989 
990 		if (MBLKL(mp) < DL_ATTACH_REQ_SIZE) {
991 			prim = DL_ATTACH_REQ;
992 			error = DL_BADPRIM;
993 			goto end_proto;
994 		}
995 		dlp = (union DL_primitives *)mp->b_rptr;
996 		prim = dlp->dl_primitive;
997 		if (prim != DL_ATTACH_REQ) {
998 			error = DL_BADPRIM;
999 			goto end_proto;
1000 		}
1001 		ppa = dlp->attach_req.dl_ppa;
1002 		ppa = (ppa%2) ? ((ppa-1)*2 +1) : (ppa*2);
1003 		if (ppa >= maxzsh) {
1004 			error = DL_BADPPA;
1005 			goto end_proto;
1006 		}
1007 		zs = &zscom[ppa];
1008 		if (zs->zs_ops == NULL) {
1009 			error = ENXIO;
1010 			goto end_proto;
1011 		}
1012 		mutex_enter(zs->zs_excl);
1013 		if ((zs->zs_ops != &zsops_null) &&
1014 		    (zs->zs_ops != &zsops_hdlc)) {
1015 			/*
1016 			 * another protocol got here first
1017 			 */
1018 			error = (EBUSY);
1019 			mutex_exit(zs->zs_excl);
1020 			goto end_proto;
1021 
1022 		}
1023 
1024 		stp->str_com = (caddr_t)zs;
1025 		mutex_exit(zs->zs_excl);
1026 end_proto:
1027 		if (error)
1028 			dlerrorack(wq, mp, prim, error, 0);
1029 		else
1030 			dlokack(wq, mp, DL_ATTACH_REQ);
1031 		break;
1032 
1033 	case M_IOCTL:
1034 		zsh_ioctl(wq, mp);
1035 		break;
1036 
1037 	case M_IOCDATA:
1038 		resp = (struct copyresp *)mp->b_rptr;
1039 		if (resp->cp_rval) {
1040 			/*
1041 			 * Just free message on failure.
1042 			 */
1043 			freemsg(mp);
1044 			break;
1045 		}
1046 
1047 		switch (resp->cp_cmd) {
1048 
1049 		case S_IOCGETMODE:
1050 		case S_IOCGETSTATS:
1051 		case S_IOCGETSPEED:
1052 		case S_IOCGETMCTL:
1053 		case S_IOCGETMRU:
1054 			mioc2ack(mp, NULL, 0, 0);
1055 			qreply(wq, mp);
1056 			break;
1057 
1058 		case S_IOCSETMODE:
1059 			zss  = (struct syncline *)&zs->zs_priv_str;
1060 			mutex_enter(zs->zs_excl);
1061 			error = zsh_setmode(zs, zss,
1062 			    (struct scc_mode *)mp->b_cont->b_rptr);
1063 			if (error) {
1064 				register struct iocblk  *iocp =
1065 				    (struct iocblk *)mp->b_rptr;
1066 				mp->b_datap->db_type = M_IOCNAK;
1067 				iocp->ioc_error = error;
1068 			} else
1069 				mioc2ack(mp, NULL, 0, 0);
1070 			mutex_exit(zs->zs_excl);
1071 			qreply(wq, mp);
1072 			break;
1073 
1074 		case S_IOCSETMRU:
1075 			zss  = (struct syncline *)&zs->zs_priv_str;
1076 			mutex_enter(zs->zs_excl);
1077 			zss->sl_mru = *(int *)mp->b_cont->b_rptr;
1078 			mutex_exit(zs->zs_excl);
1079 			mioc2ack(mp, NULL, 0, 0);
1080 			qreply(wq, mp);
1081 			break;
1082 		default:
1083 			freemsg(mp);
1084 		}
1085 		break;
1086 
1087 		/*
1088 		 * We're at the bottom of the food chain, so we flush our
1089 		 * write queue, clear the FLUSHW bit so it doesn't go round
1090 		 * and round forever, then flush our read queue (since there's
1091 		 * no read put procedure down here) and pass it up for any
1092 		 * higher modules to deal with in their own way.
1093 		 */
1094 	case M_FLUSH:
1095 		if (*mp->b_rptr & FLUSHW) {
1096 			mutex_enter(zs->zs_excl);
1097 			flushq(wq, FLUSHDATA);
1098 			mutex_enter(zs->zs_excl_hi);
1099 			tmp = zss->sl_xstandby;
1100 			zss->sl_xstandby = NULL;
1101 			mutex_exit(zs->zs_excl_hi);
1102 			if (tmp)
1103 				freemsg(tmp);
1104 			mutex_exit(zs->zs_excl);
1105 			*mp->b_rptr &= ~FLUSHW;
1106 		}
1107 
1108 		if (*mp->b_rptr & FLUSHR) {
1109 			mutex_enter(zs->zs_excl);
1110 			ZSH_FLUSHQ;
1111 			mutex_exit(zs->zs_excl);
1112 			qreply(wq, mp);  /* let the read queues have at it */
1113 		} else
1114 			freemsg(mp);
1115 		break;
1116 
1117 	default:
1118 		/*
1119 		 * "No, I don't want a subscription to Chain Store Age,
1120 		 * thank you anyway."
1121 		 */
1122 		freemsg(mp);
1123 		break;
1124 	}
1125 
1126 	TRACE_1(TR_ZSH, TR_ZSH_WPUT_END, "zsh_wput end: zs = %p", zs);
1127 }
1128 
1129 /*
1130  * Get the next message from the write queue, set up the necessary pointers,
1131  * state info, etc., and start the transmit "engine" by sending the first
1132  * character.  We'll then rotate through txint until done, then get an xsint.
1133  */
1134 static int
1135 zsh_start(struct zscom *zs, struct syncline *zss)
1136 {
1137 	register mblk_t *mp;
1138 	register uchar_t *wptr;
1139 	register uchar_t *rptr;
1140 	register uchar_t sl_flags = zss->sl_flags;
1141 
1142 	/*
1143 	 * Attempt to grab the next M_DATA message off the queue (that's
1144 	 * all that will be left after wput) and begin transmission.
1145 	 * This routine is normally called after completion of a previous
1146 	 * frame, or when zsh_wput gets a new message.  If we are in a
1147 	 * mode that put us in the TX_RTS state, waiting for CTS, and CTS
1148 	 * is not up yet, we have no business here.  Ditto if we're in
1149 	 * either the TX_ACTIVE or TX_CRC states.  In these cases we
1150 	 * don't clear SF_CALLSTART, so we don't forget there's work to do.
1151 	 */
1152 
1153 	TRACE_1(TR_ZSH, TR_ZSH_START_START,
1154 	    "zsh_start start: zs = %p", zs);
1155 
1156 	if (sl_flags & SF_PHONY) {
1157 		sl_flags &= ~SF_PHONY;
1158 		SCC_BIC(15, ZSR15_CTS);
1159 		SCC_BIC(5, ZSWR5_RTS);
1160 		SCC_WRITE0(ZSWR0_RESET_TXINT);
1161 		SCC_BIC(5, ZSWR5_TX_ENABLE);
1162 		zss->sl_rr0 &= ~ZSRR0_CTS;
1163 		zss->sl_txstate = TX_IDLE;
1164 		/*
1165 		 * if we get another msg by chance zsh_watchog will start
1166 		 */
1167 		sl_flags &= ~SF_XMT_INPROG;
1168 		zss->sl_flags = sl_flags;
1169 
1170 		TRACE_1(TR_ZSH, TR_ZSH_START_END,
1171 		    "zsh_start end: zs = %d", zs);
1172 
1173 		return (0);
1174 	}
1175 	mp = zss->sl_xstandby;
1176 	if (mp == NULL) {
1177 		if (!(sl_flags & SF_FDXPTP)) {
1178 			sl_flags |= SF_PHONY;
1179 			ZSH_ALLOCB(mp);
1180 			if (!mp)
1181 				return (0);
1182 			mp->b_datap->db_type = M_RSE;
1183 			mp->b_wptr = mp->b_rptr + 1;
1184 			goto transmit;
1185 		}
1186 		sl_flags &= ~SF_XMT_INPROG;
1187 		zss->sl_flags = sl_flags;
1188 
1189 		TRACE_1(TR_ZSH, TR_ZSH_START_END,
1190 		    "zsh_start end: zs = %p", zs);
1191 
1192 		return (0);
1193 	}
1194 
1195 transmit:
1196 	zss->sl_xstandby = NULL;
1197 	rptr = mp->b_rptr;
1198 	wptr = mp->b_wptr;
1199 	ZSSETSOFT(zs);
1200 
1201 #ifdef ZSH_DEBUG
1202 	if (zss->sl_xhead || zss->sl_xactb) {
1203 		debug_enter("xhead1");
1204 	}
1205 #endif
1206 
1207 	zss->sl_xhead = mp;
1208 	zss->sl_xactb = mp;
1209 	zss->sl_wd_count = zsh_timer_count;
1210 	zss->sl_txstate = TX_ACTIVE;
1211 	zss->sl_ocnt = 0;
1212 	SCC_BIS(10, ZSWR10_UNDERRUN_ABORT);	/* abort on underrun */
1213 	SCC_WRITE0(ZSWR0_RESET_TXCRC);		/* reset transmit CRC */
1214 	zss->sl_ocnt = wptr - rptr;
1215 	mp->b_wptr = rptr; /* to tell soft to free this msg */
1216 	SCC_WRITEDATA(*rptr++);    /* resets TXINT */
1217 	zs->zs_wr_cur = rptr;
1218 	zs->zs_wr_lim = wptr;
1219 
1220 	SCC_WRITE0(ZSWR0_RESET_EOM);
1221 
1222 	TRACE_1(TR_ZSH, TR_ZSH_START_END,
1223 	    "zsh_start end: zs = %p", zs);
1224 
1225 	zss->sl_flags = sl_flags;
1226 	return (1);
1227 }
1228 
1229 
1230 /*
1231  * Process an "ioctl" message sent down to us.
1232  */
1233 static void
1234 zsh_ioctl(queue_t *wq, mblk_t *mp)
1235 {
1236 	register struct ser_str *stp = (struct ser_str *)wq->q_ptr;
1237 	register struct zscom *zs = (struct zscom *)stp->str_com;
1238 	register struct syncline *zss  = (struct syncline *)&zs->zs_priv_str;
1239 	register struct iocblk   *iocp = (struct iocblk *)mp->b_rptr;
1240 	register struct scc_mode *sm;
1241 	register struct sl_stats *st;
1242 	register uchar_t	 *msignals;
1243 	register mblk_t		 *tmp;
1244 	register int		 error = 0;
1245 
1246 	mutex_enter(zs->zs_excl);
1247 	if ((zs->zs_ops != &zsops_null) &&
1248 	    (zs->zs_ops != &zsops_hdlc)) {
1249 		/*
1250 		 * another protocol got here first
1251 		 */
1252 		error = (EBUSY);
1253 		goto end_zsh_ioctl;
1254 	}
1255 
1256 
1257 	switch (iocp->ioc_cmd) {
1258 
1259 	case S_IOCGETMODE:
1260 		tmp = allocb(sizeof (struct scc_mode), BPRI_MED);
1261 		if (tmp == NULL) {
1262 			error = EAGAIN;
1263 			break;
1264 		}
1265 		if (iocp->ioc_count != TRANSPARENT)
1266 			mioc2ack(mp, tmp, sizeof (struct scc_mode), 0);
1267 		else
1268 			mcopyout(mp, NULL, sizeof (struct scc_mode), NULL, tmp);
1269 		sm = (struct scc_mode *)mp->b_cont->b_rptr;
1270 		bcopy(&zss->sl_mode, sm, sizeof (struct scc_mode));
1271 		break;
1272 
1273 	case S_IOCGETSTATS:
1274 		tmp = allocb(sizeof (struct sl_stats), BPRI_MED);
1275 		if (tmp == NULL) {
1276 			error = EAGAIN;
1277 			break;
1278 		}
1279 		if (iocp->ioc_count != TRANSPARENT)
1280 			mioc2ack(mp, tmp, sizeof (struct sl_stats), 0);
1281 		else
1282 			mcopyout(mp, NULL, sizeof (struct sl_stats), NULL, tmp);
1283 		st = (struct sl_stats *)mp->b_cont->b_rptr;
1284 		bcopy(&zss->sl_st, st, sizeof (struct sl_stats));
1285 		break;
1286 
1287 	case S_IOCGETSPEED:
1288 		tmp = allocb(sizeof (int), BPRI_MED);
1289 		if (tmp == NULL) {
1290 			error = EAGAIN;
1291 			break;
1292 		}
1293 		if (iocp->ioc_count != TRANSPARENT)
1294 			mioc2ack(mp, tmp, sizeof (int), 0);
1295 		else
1296 			mcopyout(mp, NULL, sizeof (int), NULL, tmp);
1297 		*(int *)mp->b_cont->b_rptr = zss->sl_mode.sm_baudrate;
1298 		break;
1299 
1300 	case S_IOCGETMCTL:
1301 		tmp = allocb(sizeof (char), BPRI_MED);
1302 		if (tmp == NULL) {
1303 			error = EAGAIN;
1304 			break;
1305 		}
1306 		if (iocp->ioc_count != TRANSPARENT)
1307 			mioc2ack(mp, tmp, sizeof (char), 0);
1308 		else
1309 			mcopyout(mp, NULL, sizeof (char), NULL, tmp);
1310 		msignals = (uchar_t *)mp->b_cont->b_rptr;
1311 		*msignals = zss->sl_rr0 & (ZSRR0_CD | ZSRR0_CTS);
1312 		break;
1313 
1314 	case S_IOCGETMRU:
1315 		tmp = allocb(sizeof (int), BPRI_MED);
1316 		if (tmp == NULL) {
1317 			error = EAGAIN;
1318 			break;
1319 		}
1320 		if (iocp->ioc_count != TRANSPARENT)
1321 			mioc2ack(mp, tmp, sizeof (int), 0);
1322 		else
1323 			mcopyout(mp, NULL, sizeof (int), NULL, tmp);
1324 		*(int *)mp->b_cont->b_rptr = zss->sl_mru;
1325 		break;
1326 
1327 	case S_IOCSETMODE:
1328 		if (iocp->ioc_count != TRANSPARENT) {
1329 			error = miocpullup(mp, sizeof (struct scc_mode));
1330 			if (error != 0)
1331 				break;
1332 			error = zsh_setmode(zs, zss,
1333 			    (struct scc_mode *)mp->b_cont->b_rptr);
1334 			if (error == 0)
1335 				mioc2ack(mp, NULL, 0, 0);
1336 		} else
1337 			mcopyin(mp, NULL, sizeof (struct scc_mode), NULL);
1338 		break;
1339 
1340 	case S_IOCCLRSTATS:
1341 		mutex_enter(zs->zs_excl_hi);
1342 		bzero(&zss->sl_st, sizeof (struct sl_stats));
1343 		mutex_exit(zs->zs_excl_hi);
1344 		mioc2ack(mp, NULL, 0, 0);
1345 		break;
1346 
1347 	case S_IOCSETMRU:
1348 		if (iocp->ioc_count != TRANSPARENT) {
1349 			error = miocpullup(mp, sizeof (int));
1350 			if (error != 0)
1351 				break;
1352 			zss->sl_mru = *(int *)mp->b_cont->b_rptr;
1353 			mioc2ack(mp, NULL, 0, 0);
1354 		} else
1355 			mcopyin(mp, NULL, sizeof (int), NULL);
1356 		break;
1357 
1358 	case S_IOCSETDTR:
1359 		/*
1360 		 * The first integer of the M_DATA block that should
1361 		 * follow indicate if DTR must be set or reset
1362 		 */
1363 		error = miocpullup(mp, sizeof (int));
1364 		if (error != 0)
1365 			break;
1366 
1367 		mutex_enter(zs->zs_excl_hi);
1368 		if (*(int *)mp->b_cont->b_rptr != 0)
1369 			(void) zsmctl(zs, ZSWR5_DTR, DMBIS);
1370 		else
1371 			(void) zsmctl(zs, ZSWR5_DTR, DMBIC);
1372 		mutex_exit(zs->zs_excl_hi);
1373 		break;
1374 
1375 	default:
1376 		error = EINVAL;
1377 
1378 	}
1379 end_zsh_ioctl:
1380 	iocp->ioc_error = error;
1381 	mp->b_datap->db_type = (error) ? M_IOCNAK : M_IOCACK;
1382 	mutex_exit(zs->zs_excl);
1383 	qreply(wq, mp);
1384 }
1385 
1386 /*
1387  * Set the mode of the zsh port
1388  */
1389 
1390 int
1391 zsh_setmode(struct zscom *zs, struct syncline *zss, struct scc_mode *sm)
1392 {
1393 	register int error = 0;
1394 	register mblk_t *mp;
1395 
1396 	mutex_enter(zs->zs_excl_hi);
1397 	if (sm->sm_rxclock == RXC_IS_PLL) {
1398 		zss->sl_mode.sm_retval = SMERR_RXC;
1399 		mutex_exit(zs->zs_excl_hi);
1400 		return (EINVAL);		/* not supported */
1401 	} else {
1402 		if (((zss->sl_mode.sm_config ^ sm->sm_config) &
1403 		    CONN_SIGNAL) != 0) { /* Changing, going... */
1404 			if (sm->sm_config & CONN_SIGNAL) { /* ...up. */
1405 				if (zss->sl_mstat == NULL) {
1406 					mutex_exit(zs->zs_excl_hi);
1407 					mp = allocb(
1408 					    sizeof (struct sl_status),
1409 					    BPRI_MED);
1410 					mutex_enter(zs->zs_excl_hi);
1411 					zss->sl_mstat = mp;
1412 				}
1413 			} else {			/* ...down. */
1414 				if ((mp = zss->sl_mstat) != NULL)
1415 					zss->sl_mstat = NULL;
1416 				mutex_exit(zs->zs_excl_hi);
1417 				if (mp)
1418 					freemsg(mp);
1419 				mutex_enter(zs->zs_excl_hi);
1420 			}
1421 		}
1422 		if (!(sm->sm_config & CONN_IBM)) {
1423 			if (sm->sm_config & CONN_HDX) {
1424 				zss->sl_mode.sm_retval = SMERR_HDX;
1425 				mutex_exit(zs->zs_excl_hi);
1426 				return (EINVAL);
1427 			}
1428 			if (sm->sm_config & CONN_MPT) {
1429 				zss->sl_mode.sm_retval = SMERR_MPT;
1430 				mutex_exit(zs->zs_excl_hi);
1431 				return (EINVAL);
1432 			}
1433 		}
1434 		zss->sl_flags &= ~SF_FDXPTP;		/* "conmode" */
1435 		if ((sm->sm_config & (CONN_HDX | CONN_MPT)) == 0)
1436 			zss->sl_flags |= SF_FDXPTP;
1437 
1438 		error = zsh_program(zs, sm);
1439 		if (!error && (zs->zs_ops != &zsops_null))
1440 			zsh_init_port(zs, zss);
1441 	}
1442 	mutex_exit(zs->zs_excl_hi);
1443 
1444 	return (error);
1445 }
1446 
1447 /*
1448  * Transmit interrupt service procedure
1449  */
1450 
1451 static void
1452 zsh_txint(struct zscom *zs)
1453 {
1454 	register struct syncline *zss;
1455 	register mblk_t *mp;
1456 	register int tmp;
1457 	register uchar_t *wr_cur;
1458 
1459 	TRACE_1(TR_ZSH, TR_ZSH_TXINT, "zsh_txint: zs = %p", zs);
1460 
1461 	if ((wr_cur =  zs->zs_wr_cur) != NULL && (wr_cur <  zs->zs_wr_lim)) {
1462 		SCC_WRITEDATA(*wr_cur++);
1463 		zs->zs_wr_cur = wr_cur;
1464 		return;
1465 	}
1466 
1467 
1468 	zss = (struct syncline *)&zs->zs_priv_str;
1469 
1470 	switch (zss->sl_txstate) {
1471 
1472 	/*
1473 	 * we here because end of message block lim = cur
1474 	 */
1475 	case TX_ACTIVE:
1476 
1477 		mp = zss->sl_xactb;
1478 
1479 again_txint:
1480 		mp = mp->b_cont;
1481 		if (mp) {
1482 			zss->sl_xactb = mp;
1483 			zss->sl_ocnt += tmp = mp->b_wptr - mp->b_rptr;
1484 			if (!tmp)
1485 				goto again_txint;
1486 			zs->zs_wr_cur = mp->b_rptr;
1487 			zs->zs_wr_lim = mp->b_wptr;
1488 			SCC_WRITEDATA(*zs->zs_wr_cur++);
1489 			return;
1490 		}
1491 
1492 		/*
1493 		 * This is where the fun starts.  At this point the
1494 		 * last character in the frame has been sent.  We
1495 		 * issue a RESET_TXINT so we won't get another txint
1496 		 * until the CRC has been completely sent.  Also we
1497 		 * reset the Abort-On-Underrun bit so that CRC is
1498 		 * sent at EOM, rather than an Abort.
1499 		 */
1500 		zs->zs_wr_cur = zs->zs_wr_lim = NULL;
1501 		zss->sl_txstate = TX_CRC;
1502 		SCC_WRITE0(ZSWR0_RESET_TXINT);
1503 		if (!(zss->sl_flags & SF_PHONY)) {
1504 			SCC_BIC(10, ZSWR10_UNDERRUN_ABORT);
1505 			zss->sl_st.opack++;
1506 			zss->sl_st.ochar += zss->sl_ocnt;
1507 		}
1508 		zss->sl_ocnt = 0;
1509 		ZSH_FREEMSG(zss->sl_xhead);
1510 		zss->sl_xhead = zss->sl_xactb = NULL;
1511 		ZSSETSOFT(zs);
1512 		break;
1513 	/*
1514 	 * This txint means we have sent the CRC bytes at EOF.
1515 	 * The next txint will mean we are sending or have sent the
1516 	 * flag character at EOF, but we handle that differently, and
1517 	 * enter different states,depending on whether we're IBM or not.
1518 	 */
1519 	case TX_CRC:
1520 		if (!(zss->sl_flags & SF_FDXPTP)) {
1521 			zss->sl_txstate = TX_FLAG;	/* HDX path */
1522 		} else {	/* FDX path */
1523 			if (!zsh_start(zs, zss)) {
1524 				zss->sl_txstate = TX_IDLE;
1525 				SCC_WRITE0(ZSWR0_RESET_TXINT);
1526 			}
1527 		}
1528 		break;
1529 
1530 	/*
1531 	 * This txint means the closing flag byte is going out the door.
1532 	 * We use this state to allow this to complete before dropping RTS.
1533 	 */
1534 	case TX_FLAG:
1535 		zss->sl_txstate = TX_LAST;
1536 		(void) zsh_start(zs, zss);
1537 		break;
1538 
1539 	/*
1540 	 * Arriving here means the flag should be out and it's finally
1541 	 * time to close the barn door.
1542 	 */
1543 	case TX_LAST:
1544 		zss->sl_txstate = TX_IDLE;
1545 		SCC_WRITE0(ZSWR0_RESET_TXINT);
1546 		break;
1547 
1548 	/*
1549 	 * If transmit was aborted, do nothing - watchdog will recover.
1550 	 */
1551 	case TX_ABORTED:
1552 		SCC_WRITE0(ZSWR0_RESET_TXINT);
1553 		break;
1554 
1555 	default:
1556 		SCC_WRITE0(ZSWR0_RESET_TXINT);
1557 		break;
1558 	}
1559 }
1560 
1561 /*
1562  * External Status Change interrupt service procedure
1563  */
1564 static void
1565 zsh_xsint(struct zscom *zs)
1566 {
1567 	register struct syncline *zss = (struct syncline *)&zs->zs_priv_str;
1568 	register uchar_t s0, x0;
1569 
1570 	TRACE_1(TR_ZSH, TR_ZSH_XSINT, "zsh_xsint: zs = %p", zs);
1571 
1572 	s0 = SCC_READ0();
1573 	x0 = s0 ^ zss->sl_rr0;
1574 	zss->sl_rr0 = s0;
1575 	SCC_WRITE0(ZSWR0_RESET_STATUS);
1576 
1577 	if (s0 & ZSRR0_TXUNDER) {
1578 		switch (zss->sl_txstate) {
1579 		/*
1580 		 * A transmitter underrun has occurred.  If we are not
1581 		 * here as the result of an abort sent by the watchdog
1582 		 * timeout routine, we need to send an abort to flush
1583 		 * the transmitter.  Otherwise there is a danger of
1584 		 * trashing the next frame but still sending a good crc.
1585 		 * The TX_ABORTED flag is set so that the watchdog
1586 		 * routine can initiate recovery.
1587 		 */
1588 		case TX_ACTIVE:
1589 			SCC_WRITE0(ZSWR0_SEND_ABORT);
1590 			SCC_WRITE0(ZSWR0_RESET_TXINT);
1591 			zss->sl_st.underrun++;
1592 			zsh_txbad(zs, zss);
1593 
1594 			zss->sl_txstate = TX_ABORTED;
1595 			zss->sl_wd_count = 0;
1596 			break;
1597 
1598 		case TX_CRC:
1599 			break;
1600 
1601 		case TX_FLAG:
1602 			break;
1603 
1604 		case TX_ABORTED:
1605 			break;
1606 
1607 		case TX_OFF:
1608 			break;
1609 
1610 		case TX_LAST:
1611 			break;
1612 
1613 		default:
1614 			break;
1615 		}
1616 	}
1617 
1618 	if ((x0 & ZSRR0_BREAK) && (s0 & ZSRR0_BREAK) && zs->zs_rd_cur) {
1619 		zss->sl_st.abort++;
1620 		zsh_rxbad(zs, zss);
1621 	} else if ((s0 & ZSRR0_SYNC) && (zs->zs_rd_cur)) {
1622 		/*
1623 		 * Tricky code to avoid disaster in the case where
1624 		 * an abort was detected while receiving a packet,
1625 		 * but the abort did not last long enough to be
1626 		 * detected by zsh_xsint - this can happen since
1627 		 * the ZSRR0_BREAK is not latched.  Since an abort
1628 		 * will automatically cause the SCC to enter
1629 		 * hunt mode, hopefully, the sync/hunt bit will be
1630 		 * set in this case (although if the interrupt is
1631 		 * sufficiently delayed, the SCC may have sync'ed
1632 		 * in again if it has detected a flag).
1633 		 */
1634 		zss->sl_st.abort++;
1635 		zsh_rxbad(zs, zss);
1636 	}
1637 
1638 	if (x0 & s0 & ZSRR0_CTS) {
1639 		if (zss->sl_txstate == TX_RTS) {
1640 			if (!(zss->sl_flags & SF_FDXPTP)) {
1641 				SCC_BIS(5, ZSWR5_TX_ENABLE);
1642 			}
1643 			(void) zsh_start(zs, zss);
1644 		} else if ((zss->sl_mode.sm_config &
1645 		    (CONN_IBM | CONN_SIGNAL))) {
1646 			zss->sl_flags &= ~SF_FLUSH_WQ;
1647 			zsh_setmstat(zs, CS_CTS_UP);
1648 		}
1649 	}
1650 
1651 	/*
1652 	 * We don't care about CTS transitions unless we are in either
1653 	 * IBM or SIGNAL mode, or both.  So, if we see CTS drop, and we
1654 	 * care, and we are not idle, send up a report message.
1655 	 */
1656 	if ((x0 & ZSRR0_CTS) && ((s0 & ZSRR0_CTS) == 0) &&
1657 	    (zss->sl_txstate != TX_OFF) &&
1658 	    (zss->sl_mode.sm_config & (CONN_IBM | CONN_SIGNAL))) {
1659 		SCC_BIC(15, ZSR15_CTS);
1660 		zsh_setmstat(zs, CS_CTS_DOWN);
1661 		zss->sl_flags &= ~SF_XMT_INPROG;
1662 		zss->sl_flags |= SF_FLUSH_WQ;
1663 		zss->sl_st.cts++;
1664 		if (zss->sl_txstate != TX_IDLE)
1665 			SCC_WRITE0(ZSWR0_SEND_ABORT);
1666 		SCC_WRITE0(ZSWR0_RESET_ERRORS);
1667 		SCC_WRITE0(ZSWR0_RESET_TXINT);
1668 		zss->sl_wd_count = 0;
1669 		zsh_txbad(zs, zss);
1670 	}
1671 }
1672 
1673 
1674 /*
1675  * Receive interrupt service procedure
1676  */
1677 static void
1678 zsh_rxint(struct zscom *zs)
1679 {
1680 	register struct syncline *zss = (struct syncline *)&zs->zs_priv_str;
1681 	register mblk_t *bp = zss->sl_ractb;
1682 	unsigned char *rd_cur;
1683 
1684 	TRACE_1(TR_ZSH, TR_ZSH_RXINT, "zsh_rxint: zs = %p", zs);
1685 
1686 	if (((rd_cur = zs->zs_rd_cur) != NULL) && rd_cur < zs->zs_rd_lim) {
1687 		*rd_cur++ = SCC_READDATA();
1688 		zs->zs_rd_cur = rd_cur;
1689 		return;
1690 	}
1691 
1692 	if (!rd_cur) { /* Beginning of frame */
1693 		if (!bp) {
1694 			ZSH_ALLOCB(bp);
1695 			zss->sl_ractb = bp;
1696 		}
1697 		zss->sl_rhead = bp;
1698 	} else {	/* end of data block should be cur==lim */
1699 		bp->b_wptr = zs->zs_rd_cur;
1700 		ZSH_ALLOCB(bp->b_cont);
1701 		bp = zss->sl_ractb = bp->b_cont;
1702 	}
1703 	if (!bp) {
1704 		zss->sl_st.nobuffers++;
1705 		zsh_rxbad(zs, zss);
1706 		return;
1707 	}
1708 	zs->zs_rd_cur = bp->b_wptr;
1709 	zs->zs_rd_lim = bp->b_datap->db_lim;
1710 	*zs->zs_rd_cur++ = SCC_READDATA(); /* Also resets interrupt */
1711 }
1712 
1713 
1714 /*
1715  * Special Receive Condition Interrupt routine
1716  */
1717 static void
1718 zsh_srint(struct zscom *zs)
1719 {
1720 	register struct syncline *zss = (struct syncline *)&zs->zs_priv_str;
1721 	register uchar_t s1;
1722 	register uchar_t *rd_cur;
1723 
1724 	TRACE_1(TR_ZSH, TR_ZSH_SRINT, "zsh_srint: zs = %p", zs);
1725 
1726 	SCC_READ(1, s1);
1727 
1728 	if (s1 & ZSRR1_RXEOF) {			/* end of frame */
1729 		(void) SCC_READDATA();
1730 		SCC_WRITE0(ZSWR0_RESET_ERRORS);
1731 		if (s1 & ZSRR1_FE) {		/* bad CRC */
1732 			zss->sl_st.crc++;
1733 			zsh_rxbad(zs, zss);
1734 			return;
1735 		}
1736 
1737 		if ((rd_cur = zs->zs_rd_cur) == NULL)
1738 			return;
1739 
1740 		/*
1741 		 * Drop one CRC byte from length because it came in
1742 		 * before the special interrupt got here.
1743 		 */
1744 		zss->sl_ractb->b_wptr = rd_cur - 1;
1745 
1746 		/*
1747 		 * put on done queue
1748 		 */
1749 		ZSH_PUTQ(zss->sl_rhead);
1750 		zss->sl_rhead = NULL;
1751 		zss->sl_ractb = NULL;
1752 		zs->zs_rd_cur = NULL;
1753 		zs->zs_rd_lim = NULL;
1754 		ZSSETSOFT(zs);
1755 
1756 	} else if (s1 & ZSRR1_DO) {
1757 		(void) SCC_READDATA();
1758 		SCC_WRITE0(ZSWR0_RESET_ERRORS);
1759 		zss->sl_st.overrun++;
1760 		zsh_rxbad(zs, zss);
1761 	} else
1762 		SCC_WRITE0(ZSWR0_RESET_ERRORS);
1763 }
1764 
1765 /*
1766  * Handle a second stage interrupt.
1767  * Does mostly lower priority buffer management stuff.
1768  */
1769 static int
1770 zsh_softint(struct zscom *zs)
1771 {
1772 	register struct syncline *zss;
1773 	register queue_t *q;
1774 	register mblk_t *mp, *tmp;
1775 	register mblk_t *head = NULL, *tail = NULL;
1776 	register int allocbcount = 0;
1777 	int m_error;
1778 
1779 	TRACE_1(TR_ZSH, TR_ZSH_SOFT_START, "zsh_soft start: zs = %p", zs);
1780 
1781 	mutex_enter(zs->zs_excl);
1782 	zss = (struct syncline *)zs->zs_priv;
1783 	if (!zss || (q = zss->sl_stream.str_rq) == NULL) {
1784 		mutex_exit(zs->zs_excl);
1785 		return (0);
1786 	}
1787 	m_error = zss->sl_m_error;
1788 
1789 	zss->sl_m_error = 0;
1790 
1791 
1792 	if (!zss->sl_mstat)
1793 		zss->sl_mstat = allocb(sizeof (struct sl_status), BPRI_MED);
1794 
1795 	mutex_enter(zs->zs_excl_hi);
1796 	if (zss->sl_flags & SF_FLUSH_WQ) {
1797 		if (!(zss->sl_flags & SF_FDXPTP)) {
1798 			zss->sl_flags &= ~SF_FLUSH_WQ;
1799 		} else {
1800 			register uchar_t s0;
1801 
1802 			s0 = SCC_READ0();
1803 			if (s0 & ZSRR0_CTS) {
1804 				zss->sl_rr0 |= ZSRR0_CTS;
1805 				SCC_BIS(15, ZSR15_CTS);
1806 				zss->sl_flags &= ~SF_FLUSH_WQ;
1807 				zsh_setmstat(zs, CS_CTS_UP);
1808 			}
1809 			if (zss->sl_flags & SF_FLUSH_WQ) {
1810 				mutex_exit(zs->zs_excl_hi);
1811 				flushq(WR(q), FLUSHDATA);
1812 				goto next;
1813 			}
1814 		}
1815 	}
1816 	mutex_exit(zs->zs_excl_hi);
1817 
1818 next:
1819 	for (;;) {
1820 		ZSH_GETQ(mp);
1821 		if (!mp)
1822 			break;
1823 
1824 		if (mp->b_rptr == mp->b_wptr) {
1825 			if (mp->b_datap->db_type == M_RSE) {
1826 				allocbcount++;
1827 			}
1828 			freemsg(mp);
1829 			continue;
1830 		}
1831 		if (mp->b_datap->db_type == M_DATA) {
1832 			zss->sl_st.ichar += msgdsize(mp);
1833 			zss->sl_st.ipack++;
1834 			if (!(canputnext(q))) {
1835 				zss->sl_st.ierror++;
1836 				allocbcount++;
1837 				freemsg(mp);
1838 				continue;
1839 			}
1840 		} else if (mp->b_datap->db_type == M_PROTO) {
1841 			if (!(canputnext(q))) {
1842 				freemsg(mp);
1843 				continue;
1844 			}
1845 		}
1846 		if (!head) {
1847 			allocbcount++;
1848 			zss->sl_soft_active = 1;
1849 			head = mp;
1850 		} else {
1851 			if (!tail)
1852 				tail = head;
1853 			tail->b_next = mp;
1854 			tail = mp;
1855 		}
1856 	}
1857 	if (allocbcount)
1858 		ZSH_GETBLOCK(zs, allocbcount);
1859 
1860 	tmp = NULL;
1861 again:
1862 	mutex_enter(zs->zs_excl_hi);
1863 	if (!zss->sl_xstandby) {
1864 		if (tmp) {
1865 			zss->sl_xstandby = tmp;
1866 			mutex_exit(zs->zs_excl_hi);
1867 		} else {
1868 			mutex_exit(zs->zs_excl_hi);
1869 			if (tmp = getq(WR(q)))
1870 				goto again;
1871 		}
1872 	} else {
1873 		mutex_exit(zs->zs_excl_hi);
1874 		if (tmp)
1875 			(void) putbq(WR(q), tmp);
1876 	}
1877 
1878 	mutex_exit(zs->zs_excl);
1879 
1880 	while (head) {
1881 		if (!tail) {
1882 			putnext(q, head);
1883 			break;
1884 		}
1885 		mp = head;
1886 		head = head->b_next;
1887 		mp->b_next = NULL;
1888 		putnext(q, mp);
1889 
1890 	}
1891 
1892 	if (m_error)
1893 		(void) putnextctl1(q, M_ERROR, m_error);
1894 
1895 	zss->sl_soft_active = 0;
1896 
1897 	TRACE_1(TR_ZSH, TR_ZSH_SOFT_END, "zsh_soft end: zs = %p", zs);
1898 
1899 	return (0);
1900 }
1901 
1902 /*
1903  * Initialization routine.
1904  * Sets Clock sources, baud rate, modes and miscellaneous parameters.
1905  */
1906 static int
1907 zsh_program(struct zscom *zs, struct scc_mode *sm)
1908 {
1909 	register struct syncline *zss  = (struct syncline *)&zs->zs_priv_str;
1910 	register struct zs_prog *zspp;
1911 	register ushort_t	tconst = 0;
1912 	register int	wr11 = 0;
1913 	register int	baud = 0;
1914 	register int	pll = 0;
1915 	register int	speed = 0;
1916 	register int	flags = ZSP_SYNC;
1917 	int		err = 0;
1918 
1919 	ZSSETSOFT(zs); /* get our house in order */
1920 
1921 	switch (sm->sm_txclock) {
1922 	case TXC_IS_TXC:
1923 		wr11 |= ZSWR11_TXCLK_TRXC;
1924 		break;
1925 	case TXC_IS_RXC:
1926 		wr11 |= ZSWR11_TXCLK_RTXC;
1927 		break;
1928 	case TXC_IS_BAUD:
1929 		wr11 |= ZSWR11_TXCLK_BAUD;
1930 		wr11 |= ZSWR11_TRXC_OUT_ENA + ZSWR11_TRXC_XMIT;
1931 		baud++;
1932 		break;
1933 	case TXC_IS_PLL:
1934 		wr11 |= ZSWR11_TXCLK_DPLL;
1935 		pll++;
1936 		break;
1937 	default:
1938 		zss->sl_mode.sm_retval = SMERR_TXC;
1939 		err = EINVAL;
1940 		goto out;
1941 	}
1942 	switch (sm->sm_rxclock) {
1943 	case RXC_IS_RXC:
1944 		wr11 |= ZSWR11_RXCLK_RTXC;
1945 		break;
1946 	case RXC_IS_TXC:
1947 		wr11 |= ZSWR11_RXCLK_TRXC;
1948 		break;
1949 	case RXC_IS_BAUD:
1950 		wr11 |= ZSWR11_RXCLK_BAUD;
1951 		baud++;
1952 		break;
1953 	case RXC_IS_PLL:
1954 		wr11 |= ZSWR11_RXCLK_DPLL;
1955 		pll++;
1956 		break;
1957 	default:
1958 		zss->sl_mode.sm_retval = SMERR_RXC;
1959 		err = EINVAL;
1960 		goto out;
1961 	}
1962 	if (baud && pll) {
1963 		zss->sl_mode.sm_retval = SMERR_PLL;
1964 		err = EINVAL;
1965 		goto out;
1966 	}
1967 	if (pll && !(sm->sm_config & CONN_NRZI)) {
1968 		zss->sl_mode.sm_retval = SMERR_PLL;
1969 		err = EINVAL;
1970 		goto out;
1971 	}
1972 
1973 	/*
1974 	 * If we're going to use the BRG and the speed we want is != 0...
1975 	 */
1976 	if (baud && (speed = sm->sm_baudrate)) {
1977 		tconst = (PCLK + speed) / (2 * speed) - 2;
1978 		if (tconst == 0) {
1979 			zss->sl_mode.sm_retval = SMERR_BAUDRATE;
1980 			err = EINVAL;
1981 			goto out;
1982 		}
1983 		sm->sm_baudrate = PCLK / (2 * ((int)tconst + 2));
1984 	} else {
1985 		tconst = 0;	/* Stop BRG.  Also quiesces pin 24. */
1986 	}
1987 
1988 	if (pll) {
1989 		if ((speed  = sm->sm_baudrate * 32) != 0)
1990 			tconst = (PCLK + speed) / (2 * speed) - 2;
1991 		else
1992 			tconst = 0;
1993 		if (tconst == 0) {
1994 			zss->sl_mode.sm_retval = SMERR_BAUDRATE;
1995 			err = EINVAL;
1996 			goto out;
1997 		}
1998 		speed = PCLK / (2 * ((int)tconst + 2));
1999 		sm->sm_baudrate = speed / 32;
2000 		flags |= ZSP_PLL;
2001 	}
2002 
2003 	if ((sm->sm_config & (CONN_LPBK|CONN_ECHO)) == (CONN_LPBK|CONN_ECHO)) {
2004 		zss->sl_mode.sm_retval = SMERR_LPBKS;
2005 		err = EINVAL;
2006 		goto out;
2007 	}
2008 	if (sm->sm_config & CONN_LPBK)
2009 		flags |= ZSP_LOOP;
2010 	if (sm->sm_config & CONN_NRZI)
2011 		flags |= ZSP_NRZI;
2012 	if (sm->sm_config & CONN_ECHO)
2013 		flags |= ZSP_ECHO;
2014 
2015 	zspp = &zs_prog[zs->zs_unit];
2016 
2017 	zspp->zs = zs;
2018 	zspp->flags = (uchar_t)flags;
2019 	zspp->wr4 = ZSWR4_SDLC;
2020 	zspp->wr11 = (uchar_t)wr11;
2021 	zspp->wr12 = (uchar_t)(tconst & 0xff);
2022 	zspp->wr13 = (uchar_t)((tconst >> 8) & 0xff);
2023 	zspp->wr3 = (uchar_t)(ZSWR3_RX_ENABLE | ZSWR3_RXCRC_ENABLE |
2024 	    ZSWR3_RX_8);
2025 	zspp->wr5 = (uchar_t)(ZSWR5_TX_8 | ZSWR5_DTR | ZSWR5_TXCRC_ENABLE);
2026 
2027 	if (zss->sl_flags & SF_FDXPTP) {
2028 		zspp->wr5 |= ZSWR5_RTS;
2029 		zss->sl_rr0 |= ZSRR0_CTS;		/* Assume CTS is high */
2030 	}
2031 	if (sm->sm_config & CONN_IBM) {
2032 		zspp->wr15 = (uchar_t)
2033 		    (ZSR15_TX_UNDER | ZSR15_BREAK | ZSR15_SYNC | ZSR15_CTS);
2034 		if (!(zss->sl_flags & SF_FDXPTP))
2035 			zspp->wr15 &= ~ZSR15_CTS;
2036 	} else {
2037 		zspp->wr5 |= ZSWR5_TX_ENABLE;
2038 		zspp->wr15 = (uchar_t)
2039 		    (ZSR15_TX_UNDER | ZSR15_BREAK | ZSR15_SYNC);
2040 		if (sm->sm_config & CONN_SIGNAL)
2041 			zspp->wr15 |= ZSR15_CTS;
2042 	}
2043 
2044 	zs_program(zspp);
2045 	SCC_WRITE0(ZSWR0_RESET_STATUS);		/* reset XS */
2046 	SCC_WRITE0(ZSWR0_RESET_STATUS);		/* reset XS */
2047 	zss->sl_flags |= SF_INITIALIZED;
2048 	bzero(&zss->sl_st, sizeof (struct sl_stats));
2049 	bcopy(sm, &zss->sl_mode, sizeof (struct scc_mode));
2050 	zss->sl_mode.sm_retval = 0;	/* successful */
2051 out:
2052 	return (err);
2053 }
2054 
2055 /*
2056  * Function to store modem signal changes in sl_mstat field.
2057  * Note that these events are supposed to be so far apart in time that
2058  * we should always be able to send up the event and allocate a message
2059  * block before another one happens.  If not, we'll overwrite this one.
2060  */
2061 static void
2062 zsh_setmstat(struct zscom *zs, int event)
2063 {
2064 	register struct syncline *zss = (struct syncline *)&zs->zs_priv_str;
2065 	register struct sl_status *mstat;
2066 	register mblk_t *mp;
2067 
2068 	if (((mp = zss->sl_mstat) != NULL) &&
2069 	    (zss->sl_mode.sm_config & (CONN_SIGNAL))) {
2070 		mstat = (struct sl_status *)mp->b_wptr;
2071 		mstat->type = (zss->sl_mode.sm_config & CONN_IBM) ?
2072 		    SLS_LINKERR : SLS_MDMSTAT;
2073 		mstat->status = event;
2074 		gethrestime(&mstat->tstamp);
2075 		mp->b_wptr += sizeof (struct sl_status);
2076 		mp->b_datap->db_type = M_PROTO;
2077 		ZSH_PUTQ(mp);
2078 		zss->sl_mstat = NULL;
2079 		ZSSETSOFT(zs);
2080 	}
2081 }
2082 
2083 /*
2084  * Received Bad Frame procedure
2085  */
2086 static void
2087 zsh_rxbad(struct zscom *zs, struct syncline *zss)
2088 {
2089 	/*
2090 	 * swallow bad characters
2091 	 */
2092 	(void) SCC_READDATA();
2093 	(void) SCC_READDATA();
2094 	(void) SCC_READDATA();
2095 
2096 	SCC_BIS(3, ZSWR3_HUNT);	/* enter hunt mode - ignores rest of frame */
2097 
2098 	zss->sl_st.ierror++;
2099 
2100 	/*
2101 	 * Free active receive message.
2102 	 */
2103 	if (zss->sl_rhead) {
2104 		zss->sl_rhead->b_wptr = zss->sl_rhead->b_rptr;
2105 		zss->sl_rhead->b_datap->db_type = M_RSE;
2106 		ZSH_FREEMSG(zss->sl_rhead);
2107 		zss->sl_ractb = NULL;
2108 		zs->zs_rd_cur = NULL;
2109 		zs->zs_rd_lim = NULL;
2110 	}
2111 	if (zss->sl_rhead) {
2112 		zss->sl_rhead = NULL;
2113 		ZSH_ALLOCB(zss->sl_ractb);
2114 		zs->zs_rd_cur = NULL;
2115 		zs->zs_rd_lim = NULL;
2116 	}
2117 
2118 	ZSSETSOFT(zs);
2119 }
2120 
2121 /*
2122  * Transmit error procedure
2123  */
2124 static void
2125 zsh_txbad(struct zscom *zs, struct syncline *zss)
2126 {
2127 	if (zss->sl_xhead) {		/* free the message we were sending */
2128 		zss->sl_xhead->b_wptr = zss->sl_xhead->b_rptr;
2129 		ZSH_FREEMSG(zss->sl_xhead);
2130 		zss->sl_xactb = NULL;
2131 		zs->zs_wr_cur = NULL;
2132 		zs->zs_wr_lim = NULL;
2133 	}
2134 	zss->sl_xhead = NULL;
2135 
2136 	if (!(zss->sl_flags & SF_FDXPTP)) {
2137 		/*
2138 		 * drop RTS and our notion of CTS
2139 		 */
2140 		SCC_BIC(5, ZSWR5_RTS);
2141 		SCC_BIC(5, ZSWR5_TX_ENABLE);
2142 		zss->sl_rr0 &= ~ZSRR0_CTS;
2143 	}
2144 	zss->sl_txstate = TX_IDLE;
2145 	if (!(zss->sl_flags & SF_PHONY))
2146 		zss->sl_st.oerror++;
2147 }
2148 
2149 /*
2150  * Transmitter watchdog timeout routine
2151  */
2152 static void
2153 zsh_watchdog(void *arg)
2154 {
2155 	struct zscom *zs = arg;
2156 	struct syncline *zss = (struct syncline *)&zs->zs_priv_str;
2157 	queue_t *wq;
2158 	mblk_t *mp;
2159 	int warning = 0;
2160 	uchar_t s0;
2161 	int do_flushwq = 0;
2162 
2163 	/*
2164 	 * The main reason for this routine is because, under some
2165 	 * circumstances, a transmit interrupt may get lost (ie., if
2166 	 * underrun occurs after the last character has been sent, and
2167 	 * the tx interrupt following the abort gets scheduled before
2168 	 * the current tx interrupt has been serviced).  Transmit can
2169 	 * also get hung if the cable is pulled out and the clock was
2170 	 * coming in from the modem.
2171 	 */
2172 
2173 	mutex_enter(zs->zs_excl);
2174 	if (zss->sl_stream.str_rq)
2175 		wq = WR(zss->sl_stream.str_rq);
2176 	else {
2177 		mutex_exit(zs->zs_excl);
2178 		return;		/* guard against close/callback race */
2179 	}
2180 
2181 	mutex_enter(zs->zs_excl_hi);
2182 	if (!(zss->sl_flags & SF_XMT_INPROG) && wq->q_first) {
2183 		zss->sl_flags |= SF_XMT_INPROG;
2184 		if ((zss->sl_flags & SF_FDXPTP) ||
2185 		    zsh_hdp_ok_or_rts_state(zs, zss))
2186 			(void) zsh_start(zs, zss);
2187 		goto end_watchdog;
2188 	}
2189 
2190 	if (zss->sl_wd_count-- > 0)
2191 		goto end_watchdog;
2192 
2193 	if (zss->sl_flags & SF_FLUSH_WQ) {
2194 		if (!(zss->sl_flags & SF_FDXPTP))
2195 			zss->sl_flags &= ~SF_FLUSH_WQ;
2196 		else {
2197 			s0 = SCC_READ0();
2198 			if (s0 & ZSRR0_CTS) {
2199 				zss->sl_rr0 |= ZSRR0_CTS;
2200 				SCC_BIS(15, ZSR15_CTS);
2201 				zss->sl_flags &= ~SF_FLUSH_WQ;
2202 				zsh_setmstat(zs, CS_CTS_UP);
2203 			}
2204 		}
2205 	}
2206 
2207 	switch (zss->sl_txstate) {
2208 
2209 	case TX_ABORTED:
2210 		/*
2211 		 * Transmitter was hung ... try restarting it.
2212 		 */
2213 		if (zss->sl_flags & SF_FDXPTP) {
2214 			zss->sl_flags |= SF_XMT_INPROG;
2215 			(void) zsh_start(zs, zss);
2216 		} else
2217 			do_flushwq = 1;
2218 		break;
2219 
2220 	case TX_ACTIVE:
2221 	case TX_CRC:
2222 		/*
2223 		 * Transmit is hung for some reason. Reset tx interrupt.
2224 		 * Flush transmit fifo by sending an abort command
2225 		 * which also sets the Underrun/EOM latch in WR0 and in
2226 		 * turn generates an External Status interrupt that
2227 		 * will reset the necessary message buffer pointers.
2228 		 * The watchdog timer will cycle again to allow the SCC
2229 		 * to settle down after the abort command.  The next
2230 		 * time through we'll see that the state is now TX_ABORTED
2231 		 * and call zsh_start to grab a new message.
2232 		 */
2233 		if (--zss->sl_wd_count <= 0) {
2234 			SCC_WRITE0(ZSWR0_SEND_ABORT);
2235 			SCC_WRITE0(ZSWR0_RESET_ERRORS);
2236 			SCC_WRITE0(ZSWR0_RESET_TXINT);
2237 			zsh_txbad(zs, zss);
2238 			zss->sl_txstate = TX_ABORTED; /* must be after txbad */
2239 			warning = 1;
2240 		}
2241 		break;
2242 
2243 	case TX_RTS:
2244 		/*
2245 		 * Timer expired after we raised RTS.  CTS never came up.
2246 		 */
2247 		zss->sl_st.cts++;
2248 
2249 		zsh_setmstat(zs, CS_CTS_TO);
2250 		zss->sl_flags &= ~SF_XMT_INPROG;
2251 		zss->sl_flags |= SF_FLUSH_WQ;
2252 		ZSSETSOFT(zs);
2253 		break;
2254 
2255 	default:
2256 		/*
2257 		 * If we time out in an inactive state we set a soft
2258 		 * interrupt.  This will call zsh_start which will
2259 		 * clear SF_XMT_INPROG if the queue is empty.
2260 		 */
2261 		break;
2262 	}
2263 end_watchdog:
2264 	if (zss->sl_txstate != TX_OFF) {
2265 		mutex_exit(zs->zs_excl_hi);
2266 		zss->sl_wd_id = timeout(zsh_watchdog, zs, SIO_WATCHDOG_TICK);
2267 	} else {
2268 		zss->sl_wd_id = 0;	/* safety */
2269 		mutex_exit(zs->zs_excl_hi);
2270 	}
2271 	if (warning || do_flushwq) {
2272 		flushq(wq, FLUSHDATA);
2273 		mutex_enter(zs->zs_excl_hi);
2274 		if ((mp = zss->sl_xstandby) != NULL)
2275 			zss->sl_xstandby = NULL;
2276 		mutex_exit(zs->zs_excl_hi);
2277 		if (mp)
2278 			freemsg(mp);
2279 	}
2280 	mutex_exit(zs->zs_excl);
2281 	if (warning)
2282 		cmn_err(CE_WARN, "zsh%x: transmit hung", zs->zs_unit);
2283 }
2284 
2285 static void
2286 zsh_callback(void *arg)
2287 {
2288 	struct zscom *zs = arg;
2289 	struct syncline *zss = (struct syncline *)&zs->zs_priv_str;
2290 	int tmp = ZSH_MAX_RSTANDBY;
2291 
2292 	mutex_enter(zs->zs_excl);
2293 	if (zss->sl_bufcid) {
2294 		zss->sl_bufcid = 0;
2295 		ZSH_GETBLOCK(zs, tmp);
2296 	}
2297 	mutex_exit(zs->zs_excl);
2298 }
2299