xref: /illumos-gate/usr/src/uts/sun4v/io/qcn.c (revision b0fe7b8fa79924061f3bdf7f240ea116c2c0b704)
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 2007 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 #include <sys/hsvc.h>
53 #include <sys/machsystm.h>
54 
55 /* dev_ops and cb_ops for device driver */
56 static int qcn_getinfo(dev_info_t *, ddi_info_cmd_t, void *, void **);
57 static int qcn_attach(dev_info_t *, ddi_attach_cmd_t);
58 static int qcn_detach(dev_info_t *, ddi_detach_cmd_t);
59 static int qcn_open(queue_t *, dev_t *, int, int, cred_t *);
60 static int qcn_close(queue_t *, int, cred_t *);
61 static int qcn_wput(queue_t *, mblk_t *);
62 static int qcn_wsrv(queue_t *);
63 static int qcn_rsrv(queue_t *);
64 
65 /* other internal qcn routines */
66 static void qcn_ioctl(queue_t *, mblk_t *);
67 static void qcn_reioctl(void *);
68 static void qcn_ack(mblk_t *, mblk_t *, uint_t);
69 static void qcn_start(void);
70 static int qcn_transmit_write(queue_t *, mblk_t *);
71 static int qcn_transmit_putchr(queue_t *, mblk_t *);
72 static void qcn_receive_read(void);
73 static void qcn_receive_getchr(void);
74 static void qcn_flush(void);
75 static uint_t qcn_hi_intr(caddr_t arg);
76 static uint_t qcn_soft_intr(caddr_t arg1, caddr_t arg2);
77 
78 static boolean_t abort_charseq_recognize(uchar_t);
79 
80 static qcn_t *qcn_state;
81 static uchar_t qcn_stopped = B_FALSE;
82 static int qcn_timeout_period = 20;	/* time out in seconds */
83 size_t qcn_input_dropped;	/* dropped input character counter */
84 
85 #ifdef QCN_POLLING
86 static void qcn_poll_handler(void *unused);
87 static cyc_time_t qcn_poll_time;
88 static cyc_handler_t qcn_poll_cychandler = {
89 	qcn_poll_handler,
90 	NULL,
91 	CY_LOW_LEVEL		/* XXX need softint to make this high */
92 };
93 static cyclic_id_t qcn_poll_cycid = CYCLIC_NONE;
94 static uint64_t	qcn_poll_interval = 5;  /* milli sec */
95 static uint64_t sb_interval = 0;
96 uint_t qcn_force_polling = 0;
97 #endif
98 
99 #define	QCN_MI_IDNUM		0xABCE
100 #define	QCN_MI_HIWAT		8192
101 #define	QCN_MI_LOWAT		128
102 
103 /* streams structures */
104 static struct module_info minfo = {
105 	QCN_MI_IDNUM,	/* mi_idnum		*/
106 	"qcn",		/* mi_idname		*/
107 	0,		/* mi_minpsz		*/
108 	INFPSZ,		/* mi_maxpsz		*/
109 	QCN_MI_HIWAT,	/* mi_hiwat		*/
110 	QCN_MI_LOWAT	/* mi_lowat		*/
111 };
112 
113 static struct qinit rinit = {
114 	putq,		/* qi_putp		*/
115 	qcn_rsrv,	/* qi_srvp		*/
116 	qcn_open,	/* qi_qopen		*/
117 	qcn_close,	/* qi_qclose		*/
118 	NULL,		/* qi_qadmin		*/
119 	&minfo,		/* qi_minfo		*/
120 	NULL		/* qi_mstat		*/
121 };
122 
123 static struct qinit winit = {
124 	qcn_wput,	/* qi_putp		*/
125 	qcn_wsrv,	/* qi_srvp		*/
126 	qcn_open,	/* qi_qopen		*/
127 	qcn_close,	/* qi_qclose		*/
128 	NULL,		/* qi_qadmin		*/
129 	&minfo,		/* qi_minfo		*/
130 	NULL		/* qi_mstat		*/
131 };
132 
133 static struct streamtab qcnstrinfo = {
134 	&rinit,
135 	&winit,
136 	NULL,
137 	NULL
138 };
139 
140 /* standard device driver structures */
141 static struct cb_ops qcn_cb_ops = {
142 	nulldev,		/* open()		*/
143 	nulldev,		/* close()		*/
144 	nodev,			/* strategy()		*/
145 	nodev,			/* print()		*/
146 	nodev,			/* dump()		*/
147 	nodev,			/* read()		*/
148 	nodev,			/* write()		*/
149 	nodev,			/* ioctl()		*/
150 	nodev,			/* devmap()		*/
151 	nodev,			/* mmap()		*/
152 	nodev,			/* segmap()		*/
153 	nochpoll,		/* poll()		*/
154 	ddi_prop_op,		/* prop_op()		*/
155 	&qcnstrinfo,		/* cb_str		*/
156 	D_NEW | D_MP		/* cb_flag		*/
157 };
158 
159 static struct dev_ops qcn_ops = {
160 	DEVO_REV,
161 	0,			/* refcnt		*/
162 	qcn_getinfo,		/* getinfo()		*/
163 	nulldev,		/* identify()		*/
164 	nulldev,		/* probe()		*/
165 	qcn_attach,		/* attach()		*/
166 	qcn_detach,		/* detach()		*/
167 	nodev,			/* reset()		*/
168 	&qcn_cb_ops,		/* cb_ops		*/
169 	(struct bus_ops *)NULL,	/* bus_ops		*/
170 	NULL			/* power()		*/
171 };
172 
173 static struct modldrv modldrv = {
174 	&mod_driverops,
175 	"sun4v console driver v%I%",
176 	&qcn_ops
177 };
178 
179 static struct modlinkage modlinkage = {
180 	MODREV_1,
181 	(void*)&modldrv,
182 	NULL
183 };
184 
185 /* driver configuration routines */
186 int
187 _init(void)
188 {
189 	int error;
190 	uint64_t	major, minor;
191 
192 	qcn_state = kmem_zalloc(sizeof (qcn_t), KM_SLEEP);
193 	qcn_state->qcn_ring = contig_mem_alloc(RINGSIZE);
194 	if (qcn_state->qcn_ring == NULL)
195 		cmn_err(CE_PANIC, "console ring allocation failed");
196 
197 	error = mod_install(&modlinkage);
198 	if (error != 0) {
199 		contig_mem_free(qcn_state->qcn_ring, RINGSIZE);
200 		kmem_free(qcn_state, sizeof (qcn_t));
201 		return (error);
202 	}
203 	/*
204 	 * check minor number to see if CONS_WRITE is supported
205 	 * if so, set up real address of the buffers for hv calls.
206 	 */
207 
208 	if (((hsvc_version(HSVC_GROUP_CORE, &major, &minor) == 0) &&
209 		(major == QCN_API_MAJOR) && (minor >= QCN_API_MINOR))) {
210 		qcn_state->cons_write_buffer =
211 					contig_mem_alloc(CONS_WR_BUF_SIZE);
212 		if (qcn_state->cons_write_buffer != NULL) {
213 			qcn_state->cons_write_buf_ra =
214 					va_to_pa(qcn_state->cons_write_buffer);
215 			qcn_state->cons_transmit = qcn_transmit_write;
216 			qcn_state->cons_receive = qcn_receive_read;
217 			qcn_state->cons_read_buf_ra =
218 					va_to_pa((char *)RING_ADDR(qcn_state));
219 		}
220 	}
221 	if (qcn_state->cons_transmit == NULL) {
222 		qcn_state->cons_transmit = qcn_transmit_putchr;
223 		qcn_state->cons_receive = qcn_receive_getchr;
224 	}
225 	return (0);
226 }
227 
228 int
229 _fini(void)
230 {
231 	/* can't remove console driver */
232 	return (EBUSY);
233 }
234 
235 int
236 _info(struct modinfo *modinfop)
237 {
238 	return (mod_info(&modlinkage, modinfop));
239 }
240 
241 static int
242 qcn_add_intrs(void)
243 {
244 	dev_info_t	*devinfo = qcn_state->qcn_dip;
245 	int		actual, count = 0;
246 	int 		x, y, rc, inum = 0;
247 
248 
249 	/* get number of interrupts */
250 	rc = ddi_intr_get_nintrs(devinfo, DDI_INTR_TYPE_FIXED, &count);
251 	if ((rc != DDI_SUCCESS) || (count == 0)) {
252 		return (DDI_FAILURE);
253 	}
254 
255 	/* Allocate an array of interrupt handles */
256 	qcn_state->qcn_intr_size = count * sizeof (ddi_intr_handle_t);
257 	qcn_state->qcn_htable = kmem_zalloc(qcn_state->qcn_intr_size, KM_SLEEP);
258 
259 	/* call ddi_intr_alloc() */
260 	rc = ddi_intr_alloc(devinfo, qcn_state->qcn_htable,
261 	    DDI_INTR_TYPE_FIXED, inum, count, &actual,
262 	    DDI_INTR_ALLOC_STRICT);
263 
264 	if ((rc != DDI_SUCCESS) || (actual == 0)) {
265 		kmem_free(qcn_state->qcn_htable, qcn_state->qcn_intr_size);
266 		return (DDI_FAILURE);
267 	}
268 
269 	if (actual < count) {
270 		for (x = 0; x < actual; x++) {
271 			(void) ddi_intr_free(qcn_state->qcn_htable[x]);
272 		}
273 
274 		kmem_free(qcn_state->qcn_htable, qcn_state->qcn_intr_size);
275 		return (DDI_FAILURE);
276 	}
277 
278 	qcn_state->qcn_intr_cnt = actual;
279 
280 	/* Get intr priority */
281 	if (ddi_intr_get_pri(qcn_state->qcn_htable[0],
282 	    &qcn_state->qcn_intr_pri) != DDI_SUCCESS) {
283 		for (x = 0; x < actual; x++) {
284 			(void) ddi_intr_free(qcn_state->qcn_htable[x]);
285 		}
286 
287 		kmem_free(qcn_state->qcn_htable, qcn_state->qcn_intr_size);
288 		return (DDI_FAILURE);
289 	}
290 
291 	/* Call ddi_intr_add_handler() */
292 	for (x = 0; x < actual; x++) {
293 		if (ddi_intr_add_handler(qcn_state->qcn_htable[x],
294 		    (ddi_intr_handler_t *)qcn_hi_intr,
295 		    (caddr_t)qcn_state, NULL) != DDI_SUCCESS) {
296 
297 			for (y = 0; y < x; y++) {
298 				(void) ddi_intr_remove_handler(
299 				    qcn_state->qcn_htable[y]);
300 			}
301 
302 			for (y = 0; y < actual; y++) {
303 				(void) ddi_intr_free(qcn_state->qcn_htable[y]);
304 			}
305 
306 			kmem_free(qcn_state->qcn_htable,
307 			    qcn_state->qcn_intr_size);
308 			return (DDI_FAILURE);
309 		}
310 	}
311 
312 	return (DDI_SUCCESS);
313 }
314 
315 static void
316 qcn_remove_intrs(void)
317 {
318 	int x;
319 	for (x = 0; x < qcn_state->qcn_intr_cnt; x++) {
320 		(void) ddi_intr_disable(qcn_state->qcn_htable[x]);
321 		(void) ddi_intr_remove_handler(qcn_state->qcn_htable[x]);
322 		(void) ddi_intr_free(qcn_state->qcn_htable[x]);
323 	}
324 	kmem_free(qcn_state->qcn_htable, qcn_state->qcn_intr_size);
325 }
326 
327 static void
328 qcn_intr_enable(void)
329 {
330 	int x;
331 
332 	for (x = 0; x < qcn_state->qcn_intr_cnt; x++) {
333 		(void) ddi_intr_enable(qcn_state->qcn_htable[x]);
334 	}
335 }
336 
337 /*
338  * qcn_attach is called at startup time.
339  * There is only once instance of this driver.
340  */
341 static int
342 qcn_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
343 {
344 	extern int ddi_create_internal_pathname(dev_info_t *, char *,
345 	    int, minor_t);
346 	uint_t soft_prip;
347 
348 #ifdef QCN_POLLING
349 	char *binding_name;
350 #endif
351 	if (cmd != DDI_ATTACH)
352 		return (DDI_FAILURE);
353 
354 	if (ddi_create_internal_pathname(dip, "qcn",
355 	    S_IFCHR, 0) != DDI_SUCCESS)
356 		return (DDI_FAILURE);
357 
358 	qcn_state->qcn_soft_pend = 0;
359 	qcn_state->qcn_hangup = 0;
360 	qcn_state->qcn_rbuf_overflow = 0;
361 
362 	/* prepare some data structures in soft state */
363 
364 	qcn_state->qcn_dip = dip;
365 
366 	qcn_state->qcn_polling = 0;
367 
368 #ifdef QCN_POLLING
369 	/*
370 	 * This test is for the sole purposes of allowing
371 	 * the console to work on older firmware releases.
372 	 */
373 	binding_name = ddi_binding_name(qcn_state->qcn_dip);
374 	if ((strcmp(binding_name, "qcn") == 0) ||
375 	    (qcn_force_polling))
376 		qcn_state->qcn_polling = 1;
377 
378 	if (qcn_state->qcn_polling) {
379 		qcn_poll_time.cyt_when = 0ull;
380 		qcn_poll_time.cyt_interval =
381 		    qcn_poll_interval * 1000ull * 1000ull;
382 		mutex_enter(&cpu_lock);
383 		qcn_poll_cycid = cyclic_add(&qcn_poll_cychandler,
384 		    &qcn_poll_time);
385 		mutex_exit(&cpu_lock);
386 	}
387 #endif
388 
389 	if (!qcn_state->qcn_polling) {
390 		if (qcn_add_intrs() != DDI_SUCCESS) {
391 			cmn_err(CE_WARN, "qcn_attach: add_intr failed\n");
392 			return (DDI_FAILURE);
393 		}
394 		if (ddi_intr_add_softint(dip, &qcn_state->qcn_softint_hdl,
395 		    DDI_INTR_SOFTPRI_MAX, qcn_soft_intr,
396 		    (caddr_t)qcn_state) != DDI_SUCCESS) {
397 			cmn_err(CE_WARN, "qcn_attach: add_soft_intr failed\n");
398 			qcn_remove_intrs();
399 			return (DDI_FAILURE);
400 		}
401 		if (ddi_intr_get_softint_pri(qcn_state->qcn_softint_hdl,
402 		    &soft_prip) != DDI_SUCCESS) {
403 			cmn_err(CE_WARN, "qcn_attach: softint_pri failed\n");
404 			(void) ddi_intr_remove_softint(
405 			    qcn_state->qcn_softint_hdl);
406 			qcn_remove_intrs();
407 			return (DDI_FAILURE);
408 		}
409 
410 	mutex_init(&qcn_state->qcn_hi_lock, NULL, MUTEX_DRIVER,
411 	    (void *)(uintptr_t)(qcn_state->qcn_intr_pri));
412 	}
413 
414 	mutex_init(&qcn_state->qcn_lock, NULL, MUTEX_DRIVER, NULL);
415 
416 	/*
417 	 *  Enable  interrupts
418 	 */
419 	if (!qcn_state->qcn_polling) {
420 		qcn_intr_enable();
421 	}
422 #ifdef QCN_DEBUG
423 	prom_printf("qcn_attach(): qcn driver attached\n");
424 #endif
425 
426 	return (DDI_SUCCESS);
427 
428 }
429 
430 /* ARGSUSED */
431 static int
432 qcn_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
433 {
434 
435 	if (cmd != DDI_DETACH)
436 		return (DDI_FAILURE);
437 
438 
439 #ifdef QCN_DEBUG
440 	prom_printf("qcn_detach(): QCN driver detached\n");
441 #endif
442 
443 #ifdef QCN_POLLING
444 	if (qcn_state->qcn_polling) {
445 		mutex_enter(&cpu_lock);
446 		if (qcn_poll_cycid != CYCLIC_NONE)
447 			cyclic_remove(qcn_poll_cycid);
448 		qcn_poll_cycid = CYCLIC_NONE;
449 		mutex_exit(&cpu_lock);
450 	}
451 #endif
452 
453 	if (!qcn_state->qcn_polling)
454 		qcn_remove_intrs();
455 
456 	return (DDI_SUCCESS);
457 }
458 
459 /* ARGSUSED */
460 static int
461 qcn_getinfo(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result)
462 {
463 	int error = DDI_FAILURE;
464 	int instance = 0;
465 	switch (infocmd) {
466 	case DDI_INFO_DEVT2DEVINFO:
467 		if (qcn_state) {
468 #ifdef QCN_DEBUG
469 			prom_printf("qcn_getinfo(): devt2dip %lx\n", arg);
470 #endif
471 			*result = (void *)qcn_state->qcn_dip;
472 			error = DDI_SUCCESS;
473 		}
474 		break;
475 
476 	case DDI_INFO_DEVT2INSTANCE:
477 #ifdef QCN_DEBUG
478 		prom_printf("qcn_getinfo(): devt2instance %lx\n", arg);
479 #endif
480 		if (getminor((dev_t)arg) == 0) {
481 			*result = (void *)(uintptr_t)instance;
482 			error = DDI_SUCCESS;
483 		}
484 		break;
485 	}
486 
487 	return (error);
488 }
489 
490 /* streams open & close */
491 /* ARGSUSED */
492 static int
493 qcn_open(queue_t *q, dev_t *devp, int oflag, int sflag, cred_t *credp)
494 {
495 	tty_common_t *tty;
496 	int unit = getminor(*devp);
497 
498 #ifdef QCN_DEBUG
499 	prom_printf("qcn_open(): minor %x\n", unit);
500 #endif
501 
502 	if (unit != 0)
503 		return (ENXIO);
504 
505 	/* stream already open */
506 	if (q->q_ptr != NULL)
507 		return (DDI_SUCCESS);
508 
509 	if (!qcn_state) {
510 		cmn_err(CE_WARN, "qcn_open: console was not configured by "
511 		    "autoconfig\n");
512 		return (ENXIO);
513 	}
514 
515 	mutex_enter(&qcn_state->qcn_lock);
516 	tty = &(qcn_state->qcn_tty);
517 
518 	tty->t_readq = q;
519 	tty->t_writeq = WR(q);
520 
521 	/* Link the RD and WR Q's */
522 	q->q_ptr = WR(q)->q_ptr = (caddr_t)qcn_state;
523 	qcn_state->qcn_readq = RD(q);
524 	qcn_state->qcn_writeq = WR(q);
525 	qprocson(q);
526 
527 	mutex_exit(&qcn_state->qcn_lock);
528 
529 #ifdef QCN_DEBUG
530 	prom_printf("qcn_open: opened as dev %lx\n", *devp);
531 #endif
532 
533 	return (DDI_SUCCESS);
534 }
535 
536 /* ARGSUSED */
537 static int
538 qcn_close(queue_t *q, int flag, cred_t *credp)
539 {
540 
541 	ASSERT(qcn_state == q->q_ptr);
542 
543 	if (qcn_state->qcn_wbufcid != 0) {
544 		unbufcall(qcn_state->qcn_wbufcid);
545 	}
546 	ttycommon_close(&qcn_state->qcn_tty);
547 
548 	qprocsoff(q);
549 	q->q_ptr = WR(q)->q_ptr = NULL;
550 	qcn_state->qcn_readq = NULL;
551 	qcn_state->qcn_writeq = NULL;
552 
553 	return (DDI_SUCCESS);
554 }
555 
556 /*
557  * Put procedure for write queue.
558  * Respond to M_IOCTL, M_DATA and M_FLUSH messages here;
559  * It put's the data onto internal qcn_output_q.
560  */
561 static int
562 qcn_wput(queue_t *q, mblk_t *mp)
563 {
564 
565 #ifdef QCN_DEBUG
566 	struct iocblk *iocp;
567 	int i;
568 #endif
569 
570 	ASSERT(qcn_state == q->q_ptr);
571 
572 	if (!mp->b_datap) {
573 		cmn_err(CE_PANIC, "qcn_wput: null datap");
574 	}
575 
576 #ifdef QCN_DEBUG
577 	prom_printf("qcn_wput(): QCN wput q=%X mp=%X rd=%X wr=%X type=%X\n",
578 		q, mp, mp->b_rptr, mp->b_wptr, mp->b_datap->db_type);
579 #endif
580 
581 	mutex_enter(&qcn_state->qcn_lock);
582 
583 	switch (mp->b_datap->db_type) {
584 	case M_IOCTL:
585 	case M_CTL:
586 #ifdef QCN_DEBUG
587 		iocp = (struct iocblk *)mp->b_rptr;
588 		prom_printf("qcn_wput(): M_IOCTL cmd=%X TIOC=%X\n",
589 		    iocp->ioc_cmd, TIOC);
590 #endif
591 		switch (((struct iocblk *)mp->b_rptr)->ioc_cmd) {
592 		case TCSETSW:
593 		case TCSETSF:
594 		case TCSETAW:
595 		case TCSETAF:
596 		case TCSBRK:
597 			/*
598 			 * The change do not take effect until all
599 			 * output queued before them is drained.
600 			 * Put this message on the queue, so that
601 			 * "qcn_start" will see it when it's done
602 			 * with the output before it. Poke the start
603 			 * routine, just in case.
604 			 */
605 			(void) putq(q, mp);
606 			qcn_start();
607 			break;
608 		default:
609 			mutex_exit(&qcn_state->qcn_lock);
610 			qcn_ioctl(q, mp);
611 			mutex_enter(&qcn_state->qcn_lock);
612 		}
613 		break;
614 
615 	case M_FLUSH:
616 		if (*mp->b_rptr & FLUSHW) {
617 			flushq(q, FLUSHDATA);
618 			*mp->b_rptr &= ~FLUSHW;
619 		}
620 		if (*mp->b_rptr & FLUSHR) {
621 			flushq(RD(q), FLUSHDATA);
622 			qreply(q, mp);
623 		} else {
624 			freemsg(mp);
625 		}
626 		break;
627 
628 	case M_STOP:
629 		qcn_stopped = B_TRUE;
630 		freemsg(mp);
631 		break;
632 
633 	case M_START:
634 		qcn_stopped = B_FALSE;
635 		freemsg(mp);
636 		qenable(q);	/* Start up delayed messages */
637 		break;
638 
639 	case M_DATA:
640 		/*
641 		 * Queue the message up to be transmitted,
642 		 * and poke the start routine.
643 		 */
644 #ifdef QCN_DEBUG
645 		if (mp->b_rptr < mp->b_wptr) {
646 		prom_printf("qcn_wput(): DATA q=%X mp=%X rd=%X wr=%X\n",
647 			q, mp, mp->b_rptr, mp->b_wptr);
648 		prom_printf("qcn_wput(): [");
649 		for (i = 0; i < mp->b_wptr-mp->b_rptr; i++) {
650 			prom_printf("%c", *(mp->b_rptr+i));
651 		}
652 		prom_printf("]\n");
653 		}
654 #endif /* QCN_DEBUG */
655 		(void) putq(q, mp);
656 		qcn_start();
657 		break;
658 
659 	default:
660 		freemsg(mp);
661 	}
662 
663 	mutex_exit(&qcn_state->qcn_lock);
664 
665 	return (0);
666 }
667 
668 /*
669  * Process an "ioctl" message sent down to us.
670  */
671 static void
672 qcn_ioctl(queue_t *q, mblk_t *mp)
673 {
674 	struct iocblk	*iocp;
675 	tty_common_t	*tty;
676 	mblk_t		*datamp;
677 	int		data_size;
678 	int		error = 0;
679 
680 #ifdef QCN_DEBUG
681 	prom_printf("qcn_ioctl(): q=%X mp=%X\n", q, mp);
682 #endif
683 
684 	iocp = (struct iocblk *)mp->b_rptr;
685 	tty = &(qcn_state->qcn_tty);
686 
687 	if (tty->t_iocpending != NULL) {
688 		freemsg(tty->t_iocpending);
689 		tty->t_iocpending = NULL;
690 	}
691 	data_size = ttycommon_ioctl(tty, q, mp, &error);
692 	if (data_size != 0) {
693 		if (qcn_state->qcn_wbufcid)
694 			unbufcall(qcn_state->qcn_wbufcid);
695 		/* call qcn_reioctl() */
696 		qcn_state->qcn_wbufcid =
697 		    bufcall(data_size, BPRI_HI, qcn_reioctl, qcn_state);
698 		return;
699 	}
700 
701 	mutex_enter(&qcn_state->qcn_lock);
702 
703 	if (error < 0) {
704 		iocp = (struct iocblk *)mp->b_rptr;
705 		/*
706 		 * "ttycommon_ioctl" didn't do anything; we process it here.
707 		 */
708 		error = 0;
709 		switch (iocp->ioc_cmd) {
710 		case TCSBRK:
711 		case TIOCSBRK:
712 		case TIOCCBRK:
713 		case TIOCMSET:
714 		case TIOCMBIS:
715 		case TIOCMBIC:
716 			if (iocp->ioc_count != TRANSPARENT)
717 				qcn_ack(mp, NULL, 0);
718 			else
719 				mcopyin(mp, NULL, sizeof (int), NULL);
720 			break;
721 
722 		case TIOCMGET:
723 			datamp = allocb(sizeof (int), BPRI_MED);
724 			if (datamp == NULL) {
725 				error = EAGAIN;
726 				break;
727 			}
728 
729 			*(int *)datamp->b_rptr = 0;
730 
731 			if (iocp->ioc_count != TRANSPARENT)
732 				qcn_ack(mp, datamp, sizeof (int));
733 			else
734 				mcopyout(mp, NULL, sizeof (int), NULL, datamp);
735 			break;
736 
737 		default:
738 			error = EINVAL;
739 			break;
740 		}
741 	}
742 	if (error != 0) {
743 		iocp->ioc_count = 0;
744 		iocp->ioc_error = error;
745 		mp->b_datap->db_type = M_IOCNAK;
746 	}
747 	mutex_exit(&qcn_state->qcn_lock);
748 	qreply(q, mp);
749 }
750 
751 static void
752 qcn_reioctl(void *unit)
753 {
754 	queue_t		*q;
755 	mblk_t		*mp;
756 	qcn_t		*qcnp = (qcn_t *)unit;
757 
758 	if (!qcnp->qcn_wbufcid)
759 		return;
760 
761 	qcnp->qcn_wbufcid = 0;
762 	if ((q = qcnp->qcn_tty.t_writeq) == NULL)
763 		return;
764 
765 	if ((mp = qcnp->qcn_tty.t_iocpending) == NULL)
766 		return;
767 
768 	qcnp->qcn_tty.t_iocpending = NULL;
769 	qcn_ioctl(q, mp);
770 }
771 
772 static void
773 qcn_ack(mblk_t *mp, mblk_t *dp, uint_t size)
774 {
775 	struct iocblk  *iocp = (struct iocblk *)mp->b_rptr;
776 
777 	mp->b_datap->db_type = M_IOCACK;
778 	iocp->ioc_count = size;
779 	iocp->ioc_error = 0;
780 	iocp->ioc_rval = 0;
781 	if (mp->b_cont != NULL)
782 		freeb(mp->b_cont);
783 	if (dp != NULL) {
784 		mp->b_cont = dp;
785 		dp->b_wptr += size;
786 	} else
787 		mp->b_cont = NULL;
788 }
789 
790 static void
791 qcn_start(void)
792 {
793 
794 	queue_t *q;
795 	mblk_t *mp;
796 	int rv;
797 
798 	ASSERT(MUTEX_HELD(&qcn_state->qcn_lock));
799 
800 	/*
801 	 * read stream queue and remove data from the queue and
802 	 * transmit them if possible
803 	 */
804 	q = qcn_state->qcn_writeq;
805 	ASSERT(q != NULL);
806 	while (mp = getq(q)) {
807 		if (mp->b_datap->db_type == M_IOCTL) {
808 			/*
809 			 * These are those IOCTLs queued up
810 			 * do it now
811 			 */
812 			mutex_exit(&qcn_state->qcn_lock);
813 			qcn_ioctl(q, mp);
814 			mutex_enter(&qcn_state->qcn_lock);
815 			continue;
816 		}
817 		/*
818 		 * M_DATA
819 		 */
820 		rv = qcn_state->cons_transmit(q, mp);
821 		if (rv == EBUSY || rv == EAGAIN)
822 			return;
823 	}
824 }
825 
826 static int
827 qcn_transmit_write(queue_t *q, mblk_t *mp)
828 {
829 	mblk_t		*bp;
830 	size_t		len;
831 	uint64_t	i;
832 	uint64_t	retval = 0;
833 
834 #ifdef QCN_DEBUG
835 	prom_printf("qcn_transmit_write(): q=%X mp=%X\n", q, mp);
836 #endif
837 
838 	while (mp) {
839 		bp = mp;
840 		len = bp->b_wptr - bp->b_rptr;
841 		/*
842 		 * Use the console write call to send a block of characters to
843 		 * the console.
844 		 */
845 		i = (len > CONS_WR_BUF_SIZE) ? CONS_WR_BUF_SIZE : len;
846 		bcopy(bp->b_rptr, qcn_state->cons_write_buffer, i);
847 		retval = hv_cnwrite(qcn_state->cons_write_buf_ra, i, &i);
848 
849 		if (retval == H_EOK) {
850 			len -= i;
851 			bp->b_rptr += i;
852 			/*
853 			 * if we have finished with this buf, free
854 			 * and get the next buf if present.
855 			 */
856 			if (len == 0) {
857 				mp = bp->b_cont;
858 				freeb(bp);
859 			}
860 		} else {
861 			(void) putbq(q, mp);
862 
863 			switch (retval) {
864 
865 			case H_EWOULDBLOCK :
866 				/*
867 				 * hypervisor cannot process the request -
868 				 * channel busy.  Try again later.
869 				 */
870 				return (EAGAIN);
871 
872 			case H_EIO :
873 				return (EIO);
874 			default :
875 				return (ENXIO);
876 			}
877 		}
878 	}
879 	return (0);
880 }
881 
882 static int
883 qcn_transmit_putchr(queue_t *q, mblk_t *mp)
884 {
885 	caddr_t		buf;
886 	mblk_t		*bp;
887 	size_t		len;
888 	uint64_t	i;
889 
890 #ifdef QCN_DEBUG
891 	prom_printf("qcn_transmit_putchr(): q=%X mp=%X\n", q, mp);
892 #endif
893 	while (mp) {
894 		bp = mp;
895 		len = bp->b_wptr - bp->b_rptr;
896 		buf = (caddr_t)bp->b_rptr;
897 		for (i = 0; i < len; i++) {
898 			if (hv_cnputchar(buf[i]) == H_EWOULDBLOCK)
899 				break;
900 		}
901 		if (i != len) {
902 			bp->b_rptr += i;
903 			(void) putbq(q, mp);
904 			return (EAGAIN);
905 		}
906 		mp = bp->b_cont;
907 		freeb(bp);
908 	}
909 	return (0);
910 }
911 
912 /*
913  * called when SC first establishes console connection
914  * drop all the data on the output queue
915  */
916 static void
917 qcn_flush(void)
918 {
919 	queue_t *q;
920 	mblk_t *mp;
921 
922 	ASSERT(MUTEX_HELD(&qcn_state->qcn_lock));
923 
924 	q = qcn_state->qcn_writeq;
925 
926 	prom_printf("qcn_flush(): WARNING console output is dropped time=%lx\n",
927 	    gethrestime_sec());
928 	while (mp = getq(q))
929 		freemsg(mp);
930 }
931 
932 static void
933 qcn_trigger_softint(void)
934 {
935 	/*
936 	 * if we are not currently servicing a software interrupt
937 	 * (qcn_soft_pend == 0), trigger the service routine to run.
938 	 */
939 	if (atomic_swap_uint(&qcn_state->qcn_soft_pend, QCN_SP_DO) ==
940 				QCN_SP_IDL) {
941 		(void) ddi_intr_trigger_softint(
942 			    qcn_state->qcn_softint_hdl, NULL);
943 	}
944 }
945 
946 /*ARGSUSED*/
947 static uint_t
948 qcn_soft_intr(caddr_t arg1, caddr_t arg2)
949 {
950 	mblk_t *mp;
951 	int	cc;
952 	int	overflow_check;
953 
954 	do {
955 		(void) atomic_swap_uint(&qcn_state->qcn_soft_pend, QCN_SP_IP);
956 		mutex_enter(&qcn_state->qcn_hi_lock);
957 		cc = RING_CNT(qcn_state);
958 		mutex_exit(&qcn_state->qcn_hi_lock);
959 		if (cc <= 0) {
960 			goto out;
961 		}
962 
963 		if ((mp = allocb(cc, BPRI_MED)) == NULL) {
964 			mutex_enter(&qcn_state->qcn_hi_lock);
965 			qcn_input_dropped += cc;
966 			mutex_exit(&qcn_state->qcn_hi_lock);
967 			cmn_err(CE_WARN, "qcn_intr: allocb"
968 			    "failed (console input dropped)");
969 			goto out;
970 		}
971 
972 		mutex_enter(&qcn_state->qcn_hi_lock);
973 		do {
974 			/* put console input onto stream */
975 			*(char *)mp->b_wptr++ = RING_GET(qcn_state);
976 		} while (--cc);
977 
978 		if ((overflow_check = qcn_state->qcn_rbuf_overflow) != 0) {
979 			qcn_state->qcn_rbuf_overflow = 0;
980 		}
981 		mutex_exit(&qcn_state->qcn_hi_lock);
982 
983 		if (overflow_check) {
984 			cmn_err(CE_WARN, "qcn: Ring buffer overflow\n");
985 		}
986 
987 		if (qcn_state->qcn_readq) {
988 			putnext(qcn_state->qcn_readq, mp);
989 		}
990 out:
991 		/*
992 		 * If there are pending transmits because hypervisor
993 		 * returned EWOULDBLOCK poke start now.
994 		 */
995 
996 		if (qcn_state->qcn_writeq != NULL) {
997 			if (qcn_state->qcn_hangup) {
998 				(void) putctl(qcn_state->qcn_readq, M_HANGUP);
999 				flushq(qcn_state->qcn_writeq, FLUSHDATA);
1000 				qcn_state->qcn_hangup = 0;
1001 			} else {
1002 				mutex_enter(&qcn_state->qcn_lock);
1003 				qcn_start();
1004 				mutex_exit(&qcn_state->qcn_lock);
1005 			}
1006 		}
1007 		/*
1008 		 * now loop if another interrupt came in (qcn_trigger_softint
1009 		 * called) while we were processing the loop
1010 		 */
1011 	} while (atomic_swap_uint(&qcn_state->qcn_soft_pend, QCN_SP_IDL) ==
1012 								QCN_SP_DO);
1013 	return (DDI_INTR_CLAIMED);
1014 }
1015 
1016 /*ARGSUSED*/
1017 static uint_t
1018 qcn_hi_intr(caddr_t arg)
1019 {
1020 	mutex_enter(&qcn_state->qcn_hi_lock);
1021 
1022 	qcn_state->cons_receive();
1023 
1024 	mutex_exit(&qcn_state->qcn_hi_lock);
1025 	qcn_trigger_softint();
1026 
1027 	return (DDI_INTR_CLAIMED);
1028 }
1029 
1030 static void
1031 qcn_receive_read(void)
1032 {
1033 	int64_t rv;
1034 	uint8_t *bufp;
1035 	int64_t	retcount = 0;
1036 	int	i;
1037 
1038 	do {
1039 		/*
1040 		 * Maximize available buffer size
1041 		 */
1042 		if (RING_CNT(qcn_state) <= 0) {
1043 			RING_INIT(qcn_state);
1044 		}
1045 		rv = hv_cnread(qcn_state->cons_read_buf_ra +
1046 				RING_POFF(qcn_state),
1047 				RING_LEFT(qcn_state),
1048 				&retcount);
1049 		bufp = RING_ADDR(qcn_state);
1050 		if (rv == H_EOK) {
1051 			/*
1052 			 * if the alternate break sequence is enabled, test
1053 			 * the buffer for the sequence and if it is there,
1054 			 * enter the debugger.
1055 			 */
1056 			if (abort_enable == KIOCABORTALTERNATE) {
1057 				for (i = 0; i < retcount; i++) {
1058 					if (abort_charseq_recognize(*bufp++)) {
1059 						abort_sequence_enter(
1060 								(char *)NULL);
1061 					}
1062 				}
1063 			}
1064 
1065 			/* put console input onto stream */
1066 			if (retcount > 0) {
1067 				/*
1068 				 * the characters are already in the ring,
1069 				 * just update the pointer so the characters
1070 				 * can be retrieved.
1071 				 */
1072 				RING_UPD(qcn_state, retcount);
1073 			}
1074 		} else {
1075 			switch (rv) {
1076 
1077 			case H_EWOULDBLOCK :
1078 				/*
1079 				 * hypervisor cannot handle the request.
1080 				 * Try again later.
1081 				 */
1082 				break;
1083 
1084 
1085 			case H_BREAK :
1086 				/*
1087 				 * on break, unless alternate break sequence is
1088 				 * enabled, enter the debugger
1089 				 */
1090 				if (abort_enable != KIOCABORTALTERNATE)
1091 					abort_sequence_enter((char *)NULL);
1092 				break;
1093 
1094 			case H_HUP :
1095 				qcn_state->qcn_hangup = 1;
1096 				break;
1097 
1098 			default :
1099 				break;
1100 			}
1101 		}
1102 	} while (rv == H_EOK);
1103 }
1104 
1105 static void
1106 qcn_receive_getchr(void)
1107 {
1108 	int64_t rv;
1109 	uint8_t	buf;
1110 
1111 	do {
1112 		rv = hv_cngetchar(&buf);
1113 		if (rv == H_EOK) {
1114 			if (abort_enable == KIOCABORTALTERNATE) {
1115 				if (abort_charseq_recognize(buf)) {
1116 					abort_sequence_enter((char *)NULL);
1117 				}
1118 			}
1119 
1120 			/* put console input onto stream */
1121 			if (RING_POK(qcn_state, 1)) {
1122 				RING_PUT(qcn_state, buf);
1123 			} else {
1124 				qcn_state->qcn_rbuf_overflow++;
1125 			}
1126 		} else {
1127 			if (rv == H_BREAK) {
1128 				if (abort_enable != KIOCABORTALTERNATE)
1129 					abort_sequence_enter((char *)NULL);
1130 			}
1131 
1132 			if (rv == H_HUP)  {
1133 				qcn_state->qcn_hangup = 1;
1134 			}
1135 			return;
1136 		}
1137 	} while (rv == H_EOK);
1138 }
1139 
1140 #ifdef QCN_POLLING
1141 /*ARGSUSED*/
1142 static void
1143 qcn_poll_handler(void *unused)
1144 {
1145 	mblk_t *mp;
1146 	int64_t rv;
1147 	uint8_t buf;
1148 	int qcn_writeq_flush = 0;
1149 
1150 	/* LINTED: E_CONSTANT_CONDITION */
1151 	while (1) {
1152 		rv = hv_cngetchar(&buf);
1153 		if (rv == H_BREAK) {
1154 			if (abort_enable != KIOCABORTALTERNATE)
1155 				abort_sequence_enter((char *)NULL);
1156 		}
1157 
1158 		if (rv == H_HUP)  {
1159 			if (qcn_state->qcn_readq) {
1160 				(void) putctl(qcn_state->qcn_readq, M_HANGUP);
1161 				qcn_writeq_flush = 1;
1162 			}
1163 			goto out;
1164 		}
1165 
1166 		if (rv != H_EOK)
1167 			goto out;
1168 
1169 		if (abort_enable == KIOCABORTALTERNATE) {
1170 			if (abort_charseq_recognize(buf)) {
1171 				abort_sequence_enter((char *)NULL);
1172 			}
1173 		}
1174 
1175 		/* put console input onto stream */
1176 		if (qcn_state->qcn_readq) {
1177 			if ((mp = allocb(1, BPRI_MED)) == NULL) {
1178 				qcn_input_dropped++;
1179 				cmn_err(CE_WARN, "qcn_intr: allocb"
1180 				    "failed (console input dropped)");
1181 				return;
1182 			}
1183 			*(char *)mp->b_wptr++ = buf;
1184 			putnext(qcn_state->qcn_readq, mp);
1185 		}
1186 	}
1187 out:
1188 /*
1189  * If there are pending transmits because hypervisor
1190  * returned EWOULDBLOCK poke start now.
1191  */
1192 
1193 	mutex_enter(&qcn_state->qcn_lock);
1194 	if (qcn_state->qcn_writeq != NULL) {
1195 		if (qcn_writeq_flush) {
1196 			flushq(qcn_state->qcn_writeq, FLUSHDATA);
1197 		} else {
1198 			qcn_start();
1199 		}
1200 	}
1201 	mutex_exit(&qcn_state->qcn_lock);
1202 }
1203 #endif
1204 
1205 /*
1206  * Check for abort character sequence, copied from zs_async.c
1207  */
1208 #define	CNTRL(c) ((c)&037)
1209 
1210 static boolean_t
1211 abort_charseq_recognize(uchar_t ch)
1212 {
1213 	static int state = 0;
1214 	static char sequence[] = { '\r', '~', CNTRL('b') };
1215 
1216 	if (ch == sequence[state]) {
1217 		if (++state >= sizeof (sequence)) {
1218 			state = 0;
1219 			return (B_TRUE);
1220 		}
1221 	} else {
1222 		state = (ch == sequence[0]) ? 1 : 0;
1223 	}
1224 	return (B_FALSE);
1225 }
1226 
1227 
1228 static int
1229 qcn_rsrv(queue_t *q)
1230 {
1231 	mblk_t	*mp;
1232 
1233 	if (qcn_stopped == B_TRUE)
1234 		return (0);
1235 
1236 	mutex_enter(&qcn_state->qcn_lock);
1237 
1238 	while ((mp = getq(q)) != NULL) {
1239 		if (canputnext(q))
1240 			putnext(q, mp);
1241 		else if (mp->b_datap->db_type >= QPCTL)
1242 			(void) putbq(q, mp);
1243 	}
1244 
1245 	mutex_exit(&qcn_state->qcn_lock);
1246 
1247 	return (0);
1248 }
1249 
1250 /* ARGSUSED */
1251 static int
1252 qcn_wsrv(queue_t *q)
1253 {
1254 	if (qcn_stopped == B_TRUE)
1255 		return (0);
1256 
1257 	mutex_enter(&qcn_state->qcn_lock);
1258 
1259 	if (qcn_state->qcn_writeq != NULL)
1260 		qcn_start();
1261 
1262 	mutex_exit(&qcn_state->qcn_lock);
1263 
1264 	return (0);
1265 }
1266