xref: /illumos-gate/usr/src/uts/sun4v/io/qcn.c (revision e33975576e182867dfb0d525ecf5ef51154047f9)
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 /*
23  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*
30  * sun4v console driver
31  */
32 
33 #include <sys/errno.h>
34 #include <sys/stat.h>
35 #include <sys/kmem.h>
36 #include <sys/conf.h>
37 #include <sys/termios.h>
38 #include <sys/modctl.h>
39 #include <sys/kbio.h>
40 #include <sys/stropts.h>
41 #include <sys/stream.h>
42 #include <sys/strsun.h>
43 #include <sys/sysmacros.h>
44 #include <sys/promif.h>
45 #include <sys/ddi.h>
46 #include <sys/sunddi.h>
47 #include <sys/cyclic.h>
48 #include <sys/intr.h>
49 #include <sys/spl.h>
50 #include <sys/qcn.h>
51 #include <sys/hypervisor_api.h>
52 
53 /* dev_ops and cb_ops for device driver */
54 static int qcn_getinfo(dev_info_t *, ddi_info_cmd_t, void *, void **);
55 static int qcn_attach(dev_info_t *, ddi_attach_cmd_t);
56 static int qcn_detach(dev_info_t *, ddi_detach_cmd_t);
57 static int qcn_open(queue_t *, dev_t *, int, int, cred_t *);
58 static int qcn_close(queue_t *, int, cred_t *);
59 static int qcn_wput(queue_t *, mblk_t *);
60 static int qcn_wsrv(queue_t *);
61 static int qcn_rsrv(queue_t *);
62 
63 /* other internal qcn routines */
64 static void qcn_ioctl(queue_t *, mblk_t *);
65 static void qcn_reioctl(void *);
66 static void qcn_ack(mblk_t *, mblk_t *, uint_t);
67 static void qcn_start(void);
68 static int qcn_transmit(queue_t *, mblk_t *);
69 static void qcn_flush(void);
70 static uint_t qcn_hi_intr(caddr_t arg);
71 static uint_t qcn_soft_intr(caddr_t arg1, caddr_t arg2);
72 
73 static boolean_t abort_charseq_recognize(uchar_t);
74 
75 static qcn_t *qcn_state;
76 static uchar_t qcn_stopped = B_FALSE;
77 static int qcn_timeout_period = 20;	/* time out in seconds */
78 size_t qcn_input_dropped;	/* dropped input character counter */
79 
80 #ifdef QCN_POLLING
81 static void qcn_poll_handler(void *unused);
82 static cyc_time_t qcn_poll_time;
83 static cyc_handler_t qcn_poll_cychandler = {
84 	qcn_poll_handler,
85 	NULL,
86 	CY_LOW_LEVEL		/* XXX need softint to make this high */
87 };
88 static cyclic_id_t qcn_poll_cycid = CYCLIC_NONE;
89 static uint64_t	qcn_poll_interval = 5;  /* milli sec */
90 static uint64_t sb_interval = 0;
91 uint_t qcn_force_polling = 0;
92 #endif
93 
94 #define	QCN_MI_IDNUM		0xABCE
95 #define	QCN_MI_HIWAT		8192
96 #define	QCN_MI_LOWAT		128
97 
98 /* streams structures */
99 static struct module_info minfo = {
100 	QCN_MI_IDNUM,	/* mi_idnum		*/
101 	"qcn",		/* mi_idname		*/
102 	0,		/* mi_minpsz		*/
103 	INFPSZ,		/* mi_maxpsz		*/
104 	QCN_MI_HIWAT,	/* mi_hiwat		*/
105 	QCN_MI_LOWAT	/* mi_lowat		*/
106 };
107 
108 static struct qinit rinit = {
109 	putq,		/* qi_putp		*/
110 	qcn_rsrv,	/* qi_srvp		*/
111 	qcn_open,	/* qi_qopen		*/
112 	qcn_close,	/* qi_qclose		*/
113 	NULL,		/* qi_qadmin		*/
114 	&minfo,		/* qi_minfo		*/
115 	NULL		/* qi_mstat		*/
116 };
117 
118 static struct qinit winit = {
119 	qcn_wput,	/* qi_putp		*/
120 	qcn_wsrv,	/* qi_srvp		*/
121 	qcn_open,	/* qi_qopen		*/
122 	qcn_close,	/* qi_qclose		*/
123 	NULL,		/* qi_qadmin		*/
124 	&minfo,		/* qi_minfo		*/
125 	NULL		/* qi_mstat		*/
126 };
127 
128 static struct streamtab qcnstrinfo = {
129 	&rinit,
130 	&winit,
131 	NULL,
132 	NULL
133 };
134 
135 /* standard device driver structures */
136 static struct cb_ops qcn_cb_ops = {
137 	nulldev,		/* open()		*/
138 	nulldev,		/* close()		*/
139 	nodev,			/* strategy()		*/
140 	nodev,			/* print()		*/
141 	nodev,			/* dump()		*/
142 	nodev,			/* read()		*/
143 	nodev,			/* write()		*/
144 	nodev,			/* ioctl()		*/
145 	nodev,			/* devmap()		*/
146 	nodev,			/* mmap()		*/
147 	nodev,			/* segmap()		*/
148 	nochpoll,		/* poll()		*/
149 	ddi_prop_op,		/* prop_op()		*/
150 	&qcnstrinfo,		/* cb_str		*/
151 	D_NEW | D_MP		/* cb_flag		*/
152 };
153 
154 static struct dev_ops qcn_ops = {
155 	DEVO_REV,
156 	0,			/* refcnt		*/
157 	qcn_getinfo,		/* getinfo()		*/
158 	nulldev,		/* identify()		*/
159 	nulldev,		/* probe()		*/
160 	qcn_attach,		/* attach()		*/
161 	qcn_detach,		/* detach()		*/
162 	nodev,			/* reset()		*/
163 	&qcn_cb_ops,		/* cb_ops		*/
164 	(struct bus_ops *)NULL,	/* bus_ops		*/
165 	NULL			/* power()		*/
166 };
167 
168 static struct modldrv modldrv = {
169 	&mod_driverops,
170 	"sun4v console driver v%I%",
171 	&qcn_ops
172 };
173 
174 static struct modlinkage modlinkage = {
175 	MODREV_1,
176 	(void*)&modldrv,
177 	NULL
178 };
179 
180 
181 /* driver configuration routines */
182 int
183 _init(void)
184 {
185 	int error;
186 
187 	qcn_state = kmem_zalloc(sizeof (qcn_t), KM_SLEEP);
188 
189 	error = mod_install(&modlinkage);
190 	if (error != 0)
191 		kmem_free(qcn_state, sizeof (qcn_t));
192 
193 	return (error);
194 }
195 
196 int
197 _fini(void)
198 {
199 	/* can't remove console driver */
200 	return (EBUSY);
201 }
202 
203 int
204 _info(struct modinfo *modinfop)
205 {
206 	return (mod_info(&modlinkage, modinfop));
207 }
208 
209 static int
210 qcn_add_intrs(void)
211 {
212 	dev_info_t	*devinfo = qcn_state->qcn_dip;
213 	int		actual, count = 0;
214 	int 		x, y, rc, inum = 0;
215 
216 
217 	/* get number of interrupts */
218 	rc = ddi_intr_get_nintrs(devinfo, DDI_INTR_TYPE_FIXED, &count);
219 	if ((rc != DDI_SUCCESS) || (count == 0)) {
220 		return (DDI_FAILURE);
221 	}
222 
223 	/* Allocate an array of interrupt handles */
224 	qcn_state->qcn_intr_size = count * sizeof (ddi_intr_handle_t);
225 	qcn_state->qcn_htable = kmem_zalloc(qcn_state->qcn_intr_size, KM_SLEEP);
226 
227 	/* call ddi_intr_alloc() */
228 	rc = ddi_intr_alloc(devinfo, qcn_state->qcn_htable,
229 	    DDI_INTR_TYPE_FIXED, inum, count, &actual,
230 	    DDI_INTR_ALLOC_STRICT);
231 
232 	if ((rc != DDI_SUCCESS) || (actual == 0)) {
233 		kmem_free(qcn_state->qcn_htable, qcn_state->qcn_intr_size);
234 		return (DDI_FAILURE);
235 	}
236 
237 	if (actual < count) {
238 		for (x = 0; x < actual; x++) {
239 			(void) ddi_intr_free(qcn_state->qcn_htable[x]);
240 		}
241 
242 		kmem_free(qcn_state->qcn_htable, qcn_state->qcn_intr_size);
243 		return (DDI_FAILURE);
244 	}
245 
246 	qcn_state->qcn_intr_cnt = actual;
247 
248 	/* Get intr priority */
249 	if (ddi_intr_get_pri(qcn_state->qcn_htable[0],
250 	    &qcn_state->qcn_intr_pri) != DDI_SUCCESS) {
251 		for (x = 0; x < actual; x++) {
252 			(void) ddi_intr_free(qcn_state->qcn_htable[x]);
253 		}
254 
255 		kmem_free(qcn_state->qcn_htable, qcn_state->qcn_intr_size);
256 		return (DDI_FAILURE);
257 	}
258 
259 	/* Call ddi_intr_add_handler() */
260 	for (x = 0; x < actual; x++) {
261 		if (ddi_intr_add_handler(qcn_state->qcn_htable[x],
262 		    (ddi_intr_handler_t *)qcn_hi_intr,
263 		    (caddr_t)qcn_state, NULL) != DDI_SUCCESS) {
264 
265 			for (y = 0; y < x; y++) {
266 				(void) ddi_intr_remove_handler(
267 				    qcn_state->qcn_htable[y]);
268 			}
269 
270 			for (y = 0; y < actual; y++) {
271 				(void) ddi_intr_free(qcn_state->qcn_htable[y]);
272 			}
273 
274 			kmem_free(qcn_state->qcn_htable,
275 			    qcn_state->qcn_intr_size);
276 			return (DDI_FAILURE);
277 		}
278 	}
279 
280 	return (DDI_SUCCESS);
281 }
282 
283 static void
284 qcn_remove_intrs(void)
285 {
286 	int x;
287 	for (x = 0; x < qcn_state->qcn_intr_cnt; x++) {
288 		(void) ddi_intr_disable(qcn_state->qcn_htable[x]);
289 		(void) ddi_intr_remove_handler(qcn_state->qcn_htable[x]);
290 		(void) ddi_intr_free(qcn_state->qcn_htable[x]);
291 	}
292 	kmem_free(qcn_state->qcn_htable, qcn_state->qcn_intr_size);
293 }
294 
295 static void
296 qcn_intr_enable(void)
297 {
298 	int x;
299 
300 	for (x = 0; x < qcn_state->qcn_intr_cnt; x++) {
301 		(void) ddi_intr_enable(qcn_state->qcn_htable[x]);
302 	}
303 }
304 
305 /*
306  * qcn_attach is called at startup time.
307  * There is only once instance of this driver.
308  */
309 static int
310 qcn_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
311 {
312 	extern int ddi_create_internal_pathname(dev_info_t *, char *,
313 	    int, minor_t);
314 	uint_t soft_prip;
315 
316 #ifdef QCN_POLLING
317 	char *binding_name;
318 #endif
319 	if (cmd != DDI_ATTACH)
320 		return (DDI_FAILURE);
321 
322 	if (ddi_create_internal_pathname(dip, "qcn",
323 	    S_IFCHR, 0) != DDI_SUCCESS)
324 		return (DDI_FAILURE);
325 
326 	qcn_state->qcn_soft_pend = 0;
327 	qcn_state->qcn_hangup = 0;
328 	qcn_state->qcn_rbuf_overflow = 0;
329 
330 	/* prepare some data structures in soft state */
331 
332 	qcn_state->qcn_dip = dip;
333 
334 	qcn_state->qcn_polling = 0;
335 
336 #ifdef QCN_POLLING
337 	/*
338 	 * This test is for the sole purposes of allowing
339 	 * the console to work on older firmware releases.
340 	 */
341 	binding_name = ddi_binding_name(qcn_state->qcn_dip);
342 	if ((strcmp(binding_name, "qcn") == 0) ||
343 	    (qcn_force_polling))
344 		qcn_state->qcn_polling = 1;
345 
346 	if (qcn_state->qcn_polling) {
347 		qcn_poll_time.cyt_when = 0ull;
348 		qcn_poll_time.cyt_interval =
349 		    qcn_poll_interval * 1000ull * 1000ull;
350 		mutex_enter(&cpu_lock);
351 		qcn_poll_cycid = cyclic_add(&qcn_poll_cychandler,
352 		    &qcn_poll_time);
353 		mutex_exit(&cpu_lock);
354 	}
355 #endif
356 
357 	if (!qcn_state->qcn_polling) {
358 		if (qcn_add_intrs() != DDI_SUCCESS) {
359 			cmn_err(CE_WARN, "qcn_attach: add_intr failed\n");
360 			return (DDI_FAILURE);
361 		}
362 		if (ddi_intr_add_softint(dip, &qcn_state->qcn_softint_hdl,
363 		    DDI_INTR_SOFTPRI_MAX, qcn_soft_intr,
364 		    (caddr_t)qcn_state) != DDI_SUCCESS) {
365 			cmn_err(CE_WARN, "qcn_attach: add_soft_intr failed\n");
366 			qcn_remove_intrs();
367 			return (DDI_FAILURE);
368 		}
369 		if (ddi_intr_get_softint_pri(qcn_state->qcn_softint_hdl,
370 		    &soft_prip) != DDI_SUCCESS) {
371 			cmn_err(CE_WARN, "qcn_attach: softint_pri failed\n");
372 			(void) ddi_intr_remove_softint(
373 			    qcn_state->qcn_softint_hdl);
374 			qcn_remove_intrs();
375 			return (DDI_FAILURE);
376 		}
377 	qcn_state->qcn_soft_pri =
378 	    (ddi_iblock_cookie_t)(uint64_t)soft_prip;
379 
380 	mutex_init(&qcn_state->qcn_hi_lock, NULL, MUTEX_DRIVER,
381 	    (void *)(uintptr_t)(qcn_state->qcn_intr_pri));
382 	mutex_init(&qcn_state->qcn_softlock, NULL, MUTEX_DRIVER,
383 	    (void *)(qcn_state->qcn_soft_pri));
384 	}
385 
386 	mutex_init(&qcn_state->qcn_lock, NULL, MUTEX_DRIVER, NULL);
387 
388 	/*
389 	 *  Enable  interrupts
390 	 */
391 	if (!qcn_state->qcn_polling) {
392 		qcn_intr_enable();
393 	}
394 #ifdef QCN_DEBUG
395 	prom_printf("qcn_attach(): qcn driver attached\n");
396 #endif
397 
398 	return (DDI_SUCCESS);
399 
400 }
401 
402 /* ARGSUSED */
403 static int
404 qcn_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
405 {
406 
407 	if (cmd != DDI_DETACH)
408 		return (DDI_FAILURE);
409 
410 
411 #ifdef QCN_DEBUG
412 	prom_printf("qcn_detach(): QCN driver detached\n");
413 #endif
414 
415 #ifdef QCN_POLLING
416 	if (qcn_state->qcn_polling) {
417 		mutex_enter(&cpu_lock);
418 		if (qcn_poll_cycid != CYCLIC_NONE)
419 			cyclic_remove(qcn_poll_cycid);
420 		qcn_poll_cycid = CYCLIC_NONE;
421 		mutex_exit(&cpu_lock);
422 	}
423 #endif
424 
425 	if (!qcn_state->qcn_polling)
426 		qcn_remove_intrs();
427 
428 	return (DDI_SUCCESS);
429 }
430 
431 /* ARGSUSED */
432 static int
433 qcn_getinfo(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result)
434 {
435 	int error = DDI_FAILURE;
436 	int instance = 0;
437 	switch (infocmd) {
438 	case DDI_INFO_DEVT2DEVINFO:
439 		if (qcn_state) {
440 #ifdef QCN_DEBUG
441 			prom_printf("qcn_getinfo(): devt2dip %lx\n", arg);
442 #endif
443 			*result = (void *)qcn_state->qcn_dip;
444 			error = DDI_SUCCESS;
445 		}
446 		break;
447 
448 	case DDI_INFO_DEVT2INSTANCE:
449 #ifdef QCN_DEBUG
450 		prom_printf("qcn_getinfo(): devt2instance %lx\n", arg);
451 #endif
452 		if (getminor((dev_t)arg) == 0) {
453 			*result = (void *)(uintptr_t)instance;
454 			error = DDI_SUCCESS;
455 		}
456 		break;
457 	}
458 
459 	return (error);
460 }
461 
462 /* streams open & close */
463 /* ARGSUSED */
464 static int
465 qcn_open(queue_t *q, dev_t *devp, int oflag, int sflag, cred_t *credp)
466 {
467 	tty_common_t *tty;
468 	int unit = getminor(*devp);
469 
470 #ifdef QCN_DEBUG
471 	prom_printf("qcn_open(): minor %x\n", unit);
472 #endif
473 
474 	if (unit != 0)
475 		return (ENXIO);
476 
477 	/* stream already open */
478 	if (q->q_ptr != NULL)
479 		return (DDI_SUCCESS);
480 
481 	if (!qcn_state) {
482 		cmn_err(CE_WARN, "qcn_open: console was not configured by "
483 		    "autoconfig\n");
484 		return (ENXIO);
485 	}
486 
487 	mutex_enter(&qcn_state->qcn_lock);
488 	tty = &(qcn_state->qcn_tty);
489 
490 	tty->t_readq = q;
491 	tty->t_writeq = WR(q);
492 
493 	/* Link the RD and WR Q's */
494 	q->q_ptr = WR(q)->q_ptr = (caddr_t)qcn_state;
495 	qcn_state->qcn_readq = RD(q);
496 	qcn_state->qcn_writeq = WR(q);
497 	qprocson(q);
498 
499 	mutex_exit(&qcn_state->qcn_lock);
500 
501 #ifdef QCN_DEBUG
502 	prom_printf("qcn_open: opened as dev %lx\n", *devp);
503 #endif
504 
505 	return (DDI_SUCCESS);
506 }
507 
508 /* ARGSUSED */
509 static int
510 qcn_close(queue_t *q, int flag, cred_t *credp)
511 {
512 
513 	ASSERT(qcn_state == q->q_ptr);
514 
515 	if (qcn_state->qcn_wbufcid != 0) {
516 		unbufcall(qcn_state->qcn_wbufcid);
517 	}
518 	ttycommon_close(&qcn_state->qcn_tty);
519 
520 	qprocsoff(q);
521 	q->q_ptr = WR(q)->q_ptr = NULL;
522 	qcn_state->qcn_readq = NULL;
523 	qcn_state->qcn_writeq = NULL;
524 
525 	return (DDI_SUCCESS);
526 }
527 
528 /*
529  * Put procedure for write queue.
530  * Respond to M_IOCTL, M_DATA and M_FLUSH messages here;
531  * It put's the data onto internal qcn_output_q.
532  */
533 static int
534 qcn_wput(queue_t *q, mblk_t *mp)
535 {
536 
537 #ifdef QCN_DEBUG
538 	struct iocblk *iocp;
539 	int i;
540 #endif
541 
542 	ASSERT(qcn_state == q->q_ptr);
543 
544 	if (!mp->b_datap) {
545 		cmn_err(CE_PANIC, "qcn_wput: null datap");
546 	}
547 
548 #ifdef QCN_DEBUG
549 	prom_printf("qcn_wput(): QCN wput q=%X mp=%X rd=%X wr=%X type=%X\n",
550 		q, mp, mp->b_rptr, mp->b_wptr, mp->b_datap->db_type);
551 #endif
552 
553 	mutex_enter(&qcn_state->qcn_lock);
554 
555 	switch (mp->b_datap->db_type) {
556 	case M_IOCTL:
557 	case M_CTL:
558 #ifdef QCN_DEBUG
559 		iocp = (struct iocblk *)mp->b_rptr;
560 		prom_printf("qcn_wput(): M_IOCTL cmd=%X TIOC=%X\n",
561 		    iocp->ioc_cmd, TIOC);
562 #endif
563 		switch (((struct iocblk *)mp->b_rptr)->ioc_cmd) {
564 		case TCSETSW:
565 		case TCSETSF:
566 		case TCSETAW:
567 		case TCSETAF:
568 		case TCSBRK:
569 			/*
570 			 * The change do not take effect until all
571 			 * output queued before them is drained.
572 			 * Put this message on the queue, so that
573 			 * "qcn_start" will see it when it's done
574 			 * with the output before it. Poke the start
575 			 * routine, just in case.
576 			 */
577 			(void) putq(q, mp);
578 			qcn_start();
579 			break;
580 		default:
581 			qcn_ioctl(q, mp);
582 		}
583 		break;
584 
585 	case M_FLUSH:
586 		if (*mp->b_rptr & FLUSHW) {
587 			flushq(q, FLUSHDATA);
588 			*mp->b_rptr &= ~FLUSHW;
589 		}
590 		if (*mp->b_rptr & FLUSHR) {
591 			flushq(RD(q), FLUSHDATA);
592 			qreply(q, mp);
593 		} else {
594 			freemsg(mp);
595 		}
596 		break;
597 
598 	case M_STOP:
599 		qcn_stopped = B_TRUE;
600 		freemsg(mp);
601 		break;
602 
603 	case M_START:
604 		qcn_stopped = B_FALSE;
605 		freemsg(mp);
606 		qenable(q);	/* Start up delayed messages */
607 		break;
608 
609 	case M_DATA:
610 		/*
611 		 * Queue the message up to be transmitted,
612 		 * and poke the start routine.
613 		 */
614 #ifdef QCN_DEBUG
615 		if (mp->b_rptr < mp->b_wptr) {
616 		prom_printf("qcn_wput(): DATA q=%X mp=%X rd=%X wr=%X\n",
617 			q, mp, mp->b_rptr, mp->b_wptr);
618 		prom_printf("qcn_wput(): [");
619 		for (i = 0; i < mp->b_wptr-mp->b_rptr; i++) {
620 			prom_printf("%c", *(mp->b_rptr+i));
621 		}
622 		prom_printf("]\n");
623 		}
624 #endif /* QCN_DEBUG */
625 		(void) putq(q, mp);
626 		qcn_start();
627 		break;
628 
629 	default:
630 		freemsg(mp);
631 	}
632 
633 	mutex_exit(&qcn_state->qcn_lock);
634 	return (0);
635 }
636 
637 /*
638  * Process an "ioctl" message sent down to us.
639  */
640 static void
641 qcn_ioctl(queue_t *q, mblk_t *mp)
642 {
643 	struct iocblk	*iocp;
644 	tty_common_t	*tty;
645 	mblk_t		*datamp;
646 	int		data_size;
647 	int		error = 0;
648 
649 #ifdef QCN_DEBUG
650 	prom_printf("qcn_ioctl(): q=%X mp=%X\n", q, mp);
651 #endif
652 
653 	iocp = (struct iocblk *)mp->b_rptr;
654 	tty = &(qcn_state->qcn_tty);
655 
656 	if (tty->t_iocpending != NULL) {
657 		freemsg(tty->t_iocpending);
658 		tty->t_iocpending = NULL;
659 	}
660 	data_size = ttycommon_ioctl(tty, q, mp, &error);
661 	if (data_size != 0) {
662 		if (qcn_state->qcn_wbufcid)
663 			unbufcall(qcn_state->qcn_wbufcid);
664 		/* call qcn_reioctl() */
665 		qcn_state->qcn_wbufcid =
666 		    bufcall(data_size, BPRI_HI, qcn_reioctl, qcn_state);
667 		return;
668 	}
669 
670 	if (error < 0) {
671 		iocp = (struct iocblk *)mp->b_rptr;
672 		/*
673 		 * "ttycommon_ioctl" didn't do anything; we process it here.
674 		 */
675 		error = 0;
676 		switch (iocp->ioc_cmd) {
677 		case TCSBRK:
678 		case TIOCSBRK:
679 		case TIOCCBRK:
680 		case TIOCMSET:
681 		case TIOCMBIS:
682 		case TIOCMBIC:
683 			if (iocp->ioc_count != TRANSPARENT)
684 				qcn_ack(mp, NULL, 0);
685 			else
686 				mcopyin(mp, NULL, sizeof (int), NULL);
687 			break;
688 
689 		case TIOCMGET:
690 			datamp = allocb(sizeof (int), BPRI_MED);
691 			if (datamp == NULL) {
692 				error = EAGAIN;
693 				break;
694 			}
695 
696 			*(int *)datamp->b_rptr = 0;
697 
698 			if (iocp->ioc_count != TRANSPARENT)
699 				qcn_ack(mp, datamp, sizeof (int));
700 			else
701 				mcopyout(mp, NULL, sizeof (int), NULL, datamp);
702 			break;
703 
704 		default:
705 			error = EINVAL;
706 			break;
707 		}
708 	}
709 	if (error != 0) {
710 		iocp->ioc_count = 0;
711 		iocp->ioc_error = error;
712 		mp->b_datap->db_type = M_IOCNAK;
713 	}
714 	qreply(q, mp);
715 }
716 
717 static void
718 qcn_reioctl(void *unit)
719 {
720 	queue_t		*q;
721 	mblk_t		*mp;
722 	qcn_t		*qcnp = (qcn_t *)unit;
723 
724 	if (!qcnp->qcn_wbufcid)
725 		return;
726 
727 	qcnp->qcn_wbufcid = 0;
728 	if ((q = qcnp->qcn_tty.t_writeq) == NULL)
729 		return;
730 
731 	if ((mp = qcnp->qcn_tty.t_iocpending) == NULL)
732 		return;
733 
734 	qcnp->qcn_tty.t_iocpending = NULL;
735 	qcn_ioctl(q, mp);
736 }
737 
738 static void
739 qcn_ack(mblk_t *mp, mblk_t *dp, uint_t size)
740 {
741 	struct iocblk  *iocp = (struct iocblk *)mp->b_rptr;
742 
743 	mp->b_datap->db_type = M_IOCACK;
744 	iocp->ioc_count = size;
745 	iocp->ioc_error = 0;
746 	iocp->ioc_rval = 0;
747 	if (mp->b_cont != NULL)
748 		freeb(mp->b_cont);
749 	if (dp != NULL) {
750 		mp->b_cont = dp;
751 		dp->b_wptr += size;
752 	} else
753 		mp->b_cont = NULL;
754 }
755 
756 static void
757 qcn_start(void)
758 {
759 
760 	queue_t *q;
761 	mblk_t *mp;
762 	int rv;
763 
764 	ASSERT(MUTEX_HELD(&qcn_state->qcn_lock));
765 
766 	/*
767 	 * read stream queue and remove data from the queue and
768 	 * transmit them if possible
769 	 */
770 	q = qcn_state->qcn_writeq;
771 	ASSERT(q != NULL);
772 	while (mp = getq(q)) {
773 		if (mp->b_datap->db_type == M_IOCTL) {
774 			/*
775 			 * These are those IOCTLs queued up
776 			 * do it now
777 			 */
778 			qcn_ioctl(q, mp);
779 			continue;
780 		}
781 		/*
782 		 * M_DATA
783 		 */
784 		rv = qcn_transmit(q, mp);
785 		if (rv == EBUSY || rv == EAGAIN)
786 			return;
787 	}
788 }
789 
790 static int
791 qcn_transmit(queue_t *q, mblk_t *mp)
792 {
793 	caddr_t buf;
794 	mblk_t *bp;
795 	size_t len;
796 	long i;
797 
798 #ifdef QCN_DEBUG
799 	prom_printf("qcn_transmit(): q=%X mp=%X\n", q, mp);
800 #endif
801 	do {
802 		bp = mp;
803 		len = bp->b_wptr - bp->b_rptr;
804 		buf = (caddr_t)bp->b_rptr;
805 
806 		for (i = 0; i < len; i++) {
807 			if (hv_cnputchar(buf[i]) == H_EWOULDBLOCK)
808 				break;
809 		}
810 		if (i != len) {
811 			bp->b_rptr += i;
812 			(void) putbq(q, mp);
813 			return (EAGAIN);
814 		}
815 		mp = bp->b_cont;
816 		freeb(bp);
817 	} while (mp != NULL);
818 
819 	return (0);
820 }
821 
822 /*
823  * called when SC first establishes console connection
824  * drop all the data on the output queue
825  */
826 static void
827 qcn_flush(void)
828 {
829 	queue_t *q;
830 	mblk_t *mp;
831 
832 	ASSERT(MUTEX_HELD(&qcn_state->qcn_lock));
833 
834 	q = qcn_state->qcn_writeq;
835 
836 	prom_printf("qcn_flush(): WARNING console output is dropped time=%lx\n",
837 	    gethrestime_sec());
838 	while (mp = getq(q))
839 		freemsg(mp);
840 }
841 
842 static void
843 qcn_trigger_softint(void)
844 {
845 
846 	if (mutex_tryenter(&qcn_state->qcn_softlock)) {
847 		if (!qcn_state->qcn_soft_pend) {
848 			qcn_state->qcn_soft_pend = 1;
849 			mutex_exit(&qcn_state->qcn_softlock);
850 			(void) ddi_intr_trigger_softint(
851 			    qcn_state->qcn_softint_hdl, NULL);
852 		} else
853 			mutex_exit(&qcn_state->qcn_softlock);
854 	}
855 }
856 
857 /*ARGSUSED*/
858 static uint_t
859 qcn_soft_intr(caddr_t arg1, caddr_t arg2)
860 {
861 	mblk_t *mp;
862 	int	cc;
863 
864 	mutex_enter(&qcn_state->qcn_softlock);
865 	mutex_enter(&qcn_state->qcn_hi_lock);
866 	if ((cc = RING_CNT(qcn_state)) <= 0) {
867 		mutex_exit(&qcn_state->qcn_hi_lock);
868 		goto out;
869 	}
870 
871 	if ((mp = allocb(cc, BPRI_MED)) == NULL) {
872 		qcn_input_dropped += cc;
873 		cmn_err(CE_WARN, "qcn_intr: allocb"
874 		    "failed (console input dropped)");
875 		mutex_exit(&qcn_state->qcn_hi_lock);
876 		goto out;
877 	}
878 
879 	do {
880 		/* put console input onto stream */
881 		*(char *)mp->b_wptr++ = RING_GET(qcn_state);
882 	} while (--cc);
883 
884 	if (qcn_state->qcn_rbuf_overflow) {
885 		mutex_exit(&qcn_state->qcn_hi_lock);
886 		cmn_err(CE_WARN, "qcn: Ring buffer overflow\n");
887 		mutex_enter(&qcn_state->qcn_hi_lock);
888 		qcn_state->qcn_rbuf_overflow = 0;
889 	}
890 
891 	mutex_exit(&qcn_state->qcn_hi_lock);
892 	if (qcn_state->qcn_readq) {
893 		putnext(qcn_state->qcn_readq, mp);
894 	}
895 out:
896 /*
897  * If there are pending transmits because hypervisor
898  * returned EWOULDBLOCK poke start now.
899  */
900 
901 	if (qcn_state->qcn_writeq != NULL) {
902 		if (qcn_state->qcn_hangup) {
903 			(void) putctl(qcn_state->qcn_readq, M_HANGUP);
904 			flushq(qcn_state->qcn_writeq, FLUSHDATA);
905 			qcn_state->qcn_hangup = 0;
906 		} else {
907 			mutex_enter(&qcn_state->qcn_lock);
908 			qcn_start();
909 			mutex_exit(&qcn_state->qcn_lock);
910 		}
911 	}
912 	qcn_state->qcn_soft_pend = 0;
913 	mutex_exit(&qcn_state->qcn_softlock);
914 	return (DDI_INTR_CLAIMED);
915 }
916 
917 /*ARGSUSED*/
918 static uint_t
919 qcn_hi_intr(caddr_t arg)
920 {
921 	int64_t rv;
922 	uint8_t buf;
923 
924 	mutex_enter(&qcn_state->qcn_hi_lock);
925 	/* LINTED: E_CONSTANT_CONDITION */
926 	while (1) {
927 		rv = hv_cngetchar(&buf);
928 		if (rv == H_BREAK) {
929 			if (abort_enable != KIOCABORTALTERNATE)
930 				abort_sequence_enter((char *)NULL);
931 		}
932 
933 		if (rv == H_HUP)  {
934 			qcn_state->qcn_hangup = 1;
935 		}
936 
937 		if (rv != H_EOK)
938 			goto out;
939 
940 		if (abort_enable == KIOCABORTALTERNATE) {
941 			if (abort_charseq_recognize(buf)) {
942 				abort_sequence_enter((char *)NULL);
943 			}
944 		}
945 
946 		/* put console input onto stream */
947 		if (RING_POK(qcn_state, 1)) {
948 			RING_PUT(qcn_state, buf);
949 		} else {
950 			qcn_state->qcn_rbuf_overflow++;
951 		}
952 	}
953 out:
954 	mutex_exit(&qcn_state->qcn_hi_lock);
955 	qcn_trigger_softint();
956 
957 	return (DDI_INTR_CLAIMED);
958 }
959 
960 #ifdef QCN_POLLING
961 /*ARGSUSED*/
962 static void
963 qcn_poll_handler(void *unused)
964 {
965 	mblk_t *mp;
966 	int64_t rv;
967 	uint8_t buf;
968 	int qcn_writeq_flush = 0;
969 
970 	/* LINTED: E_CONSTANT_CONDITION */
971 	while (1) {
972 		rv = hv_cngetchar(&buf);
973 		if (rv == H_BREAK) {
974 			if (abort_enable != KIOCABORTALTERNATE)
975 				abort_sequence_enter((char *)NULL);
976 		}
977 
978 		if (rv == H_HUP)  {
979 			if (qcn_state->qcn_readq) {
980 				(void) putctl(qcn_state->qcn_readq, M_HANGUP);
981 				qcn_writeq_flush = 1;
982 			}
983 			goto out;
984 		}
985 
986 		if (rv != H_EOK)
987 			goto out;
988 
989 		if (abort_enable == KIOCABORTALTERNATE) {
990 			if (abort_charseq_recognize(buf)) {
991 				abort_sequence_enter((char *)NULL);
992 			}
993 		}
994 
995 		/* put console input onto stream */
996 		if (qcn_state->qcn_readq) {
997 			if ((mp = allocb(1, BPRI_MED)) == NULL) {
998 				qcn_input_dropped++;
999 				cmn_err(CE_WARN, "qcn_intr: allocb"
1000 				    "failed (console input dropped)");
1001 				return;
1002 			}
1003 			*(char *)mp->b_wptr++ = buf;
1004 			putnext(qcn_state->qcn_readq, mp);
1005 		}
1006 	}
1007 out:
1008 /*
1009  * If there are pending transmits because hypervisor
1010  * returned EWOULDBLOCK poke start now.
1011  */
1012 
1013 	mutex_enter(&qcn_state->qcn_lock);
1014 	if (qcn_state->qcn_writeq != NULL) {
1015 		if (qcn_writeq_flush) {
1016 			flushq(qcn_state->qcn_writeq, FLUSHDATA);
1017 		} else {
1018 			qcn_start();
1019 		}
1020 	}
1021 	mutex_exit(&qcn_state->qcn_lock);
1022 }
1023 #endif
1024 
1025 /*
1026  * Check for abort character sequence, copied from zs_async.c
1027  */
1028 #define	CNTRL(c) ((c)&037)
1029 
1030 static boolean_t
1031 abort_charseq_recognize(uchar_t ch)
1032 {
1033 	static int state = 0;
1034 	static char sequence[] = { '\r', '~', CNTRL('b') };
1035 
1036 	if (ch == sequence[state]) {
1037 		if (++state >= sizeof (sequence)) {
1038 			state = 0;
1039 			return (B_TRUE);
1040 		}
1041 	} else {
1042 		state = (ch == sequence[0]) ? 1 : 0;
1043 	}
1044 	return (B_FALSE);
1045 }
1046 
1047 
1048 static int
1049 qcn_rsrv(queue_t *q)
1050 {
1051 	mblk_t	*mp;
1052 
1053 	if (qcn_stopped == B_TRUE)
1054 		return (0);
1055 
1056 	mutex_enter(&qcn_state->qcn_lock);
1057 
1058 	while ((mp = getq(q)) != NULL) {
1059 		if (canputnext(q))
1060 			putnext(q, mp);
1061 		else if (mp->b_datap->db_type >= QPCTL)
1062 			(void) putbq(q, mp);
1063 	}
1064 
1065 	mutex_exit(&qcn_state->qcn_lock);
1066 
1067 	return (0);
1068 }
1069 
1070 /* ARGSUSED */
1071 static int
1072 qcn_wsrv(queue_t *q)
1073 {
1074 	if (qcn_stopped == B_TRUE)
1075 		return (0);
1076 
1077 	mutex_enter(&qcn_state->qcn_lock);
1078 
1079 	if (qcn_state->qcn_writeq != NULL)
1080 		qcn_start();
1081 
1082 	mutex_exit(&qcn_state->qcn_lock);
1083 
1084 	return (0);
1085 }
1086