xref: /dflybsd-src/sys/dev/misc/dcons/dcons_os.c (revision 70e491c09b1cb18f96facdbc91052080f2a455c3)
1 /*
2  * Copyright (C) 2003,2004
3  * 	Hidetoshi Shimokawa. All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *
16  *	This product includes software developed by Hidetoshi Shimokawa.
17  *
18  * 4. Neither the name of the author nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * $FreeBSD: src/sys/dev/dcons/dcons_os.c,v 1.4 2004/10/24 12:41:04 simokawa Exp $
35  * $DragonFly: src/sys/dev/misc/dcons/dcons_os.c,v 1.13 2007/08/07 13:14:11 hasso Exp $
36  */
37 
38 #include <sys/param.h>
39 #if __FreeBSD_version >= 502122
40 #include <sys/kdb.h>
41 #include <gdb/gdb.h>
42 #endif
43 #include <sys/kernel.h>
44 #include <sys/module.h>
45 #include <sys/systm.h>
46 #include <sys/types.h>
47 #include <sys/conf.h>
48 #include <sys/cons.h>
49 #include <sys/consio.h>
50 #include <sys/tty.h>
51 #include <sys/malloc.h>
52 #include <sys/proc.h>
53 #include <sys/priv.h>
54 #include <sys/thread2.h>
55 #include <sys/ucred.h>
56 #include <sys/bus.h>
57 
58 #include "dcons.h"
59 #include "dcons_os.h"
60 
61 #include <ddb/ddb.h>
62 #include <sys/reboot.h>
63 
64 #include <sys/sysctl.h>
65 
66 #include <vm/vm.h>
67 #include <vm/vm_param.h>
68 #include <vm/pmap.h>
69 
70 #include "opt_ddb.h"
71 #include "opt_comconsole.h"
72 #include "opt_dcons.h"
73 
74 #ifndef DCONS_POLL_HZ
75 #define DCONS_POLL_HZ	100
76 #endif
77 
78 #ifndef DCONS_BUF_SIZE
79 #define DCONS_BUF_SIZE (16*1024)
80 #endif
81 
82 #ifndef DCONS_FORCE_CONSOLE
83 #define DCONS_FORCE_CONSOLE	0	/* Mostly for FreeBSD-4/DragonFly */
84 #endif
85 
86 #ifndef DCONS_FORCE_GDB
87 #define DCONS_FORCE_GDB	1
88 #endif
89 
90 #define CDEV_MAJOR      184
91 
92 static d_open_t		dcons_open;
93 static d_close_t	dcons_close;
94 static d_ioctl_t	dcons_ioctl;
95 
96 static struct dev_ops dcons_ops = {
97 	{ "dcons", CDEV_MAJOR, D_TTY | D_KQFILTER },
98 	.d_open =	dcons_open,
99 	.d_close =	dcons_close,
100 	.d_read =	ttyread,
101 	.d_write =	ttywrite,
102 	.d_ioctl =	dcons_ioctl,
103 	.d_poll =	ttypoll,
104 	.d_kqfilter =	ttykqfilter,
105 	.d_revoke =	ttyrevoke
106 };
107 
108 #ifndef KLD_MODULE
109 static char bssbuf[DCONS_BUF_SIZE];	/* buf in bss */
110 #endif
111 
112 /* global data */
113 static struct dcons_global dg;
114 struct dcons_global *dcons_conf;
115 static int poll_hz = DCONS_POLL_HZ;
116 
117 static struct dcons_softc sc[DCONS_NPORT];
118 
119 SYSCTL_NODE(_kern, OID_AUTO, dcons, CTLFLAG_RD, 0, "Dumb Console");
120 SYSCTL_INT(_kern_dcons, OID_AUTO, poll_hz, CTLFLAG_RW, &poll_hz, 0,
121 				"dcons polling rate");
122 
123 static int drv_init = 0;
124 static struct callout dcons_callout;
125 struct dcons_buf *dcons_buf;		/* for local dconschat */
126 
127 #ifdef __DragonFly__
128 #define DEV	cdev_t
129 #define THREAD	d_thread_t
130 #elif __FreeBSD_version < 500000
131 #define DEV	cdev_t
132 #define THREAD	struct proc
133 #else
134 #define DEV	struct cdev *
135 #define THREAD	struct thread
136 #endif
137 
138 
139 static void	dcons_tty_start(struct tty *);
140 static int	dcons_tty_param(struct tty *, struct termios *);
141 static void	dcons_timeout(void *);
142 static int	dcons_drv_init(int);
143 
144 static cn_probe_t	dcons_cnprobe;
145 static cn_init_t	dcons_cninit;
146 static cn_init_fini_t	dcons_cninit_fini;
147 static cn_getc_t	dcons_cngetc;
148 static cn_checkc_t 	dcons_cncheckc;
149 static cn_putc_t	dcons_cnputc;
150 
151 CONS_DRIVER(dcons, dcons_cnprobe, dcons_cninit, dcons_cninit_fini,
152 	    NULL, dcons_cngetc, dcons_cncheckc, dcons_cnputc, NULL);
153 
154 #if __FreeBSD_version >= 502122
155 static gdb_probe_f dcons_dbg_probe;
156 static gdb_init_f dcons_dbg_init;
157 static gdb_term_f dcons_dbg_term;
158 static gdb_getc_f dcons_dbg_getc;
159 static gdb_checkc_f dcons_dbg_checkc;
160 static gdb_putc_f dcons_dbg_putc;
161 
162 GDB_DBGPORT(dcons, dcons_dbg_probe, dcons_dbg_init, dcons_dbg_term,
163     dcons_dbg_checkc, dcons_dbg_getc, dcons_dbg_putc);
164 
165 extern struct gdb_dbgport *gdb_cur;
166 #endif
167 
168 #if (KDB || DDB) && ALT_BREAK_TO_DEBUGGER
169 static int
170 dcons_check_break(struct dcons_softc *dc, int c)
171 {
172 	if (c < 0)
173 		return (c);
174 
175 #if __FreeBSD_version >= 502122
176 	if (kdb_alt_break(c, &dc->brk_state)) {
177 		if ((dc->flags & DC_GDB) != 0) {
178 			if (gdb_cur == &dcons_gdb_dbgport) {
179 				kdb_dbbe_select("gdb");
180 				breakpoint();
181 			}
182 		} else
183 			breakpoint();
184 	}
185 #else
186 	switch (dc->brk_state) {
187 	case STATE1:
188 		if (c == KEY_TILDE)
189 			dc->brk_state = STATE2;
190 		else
191 			dc->brk_state = STATE0;
192 		break;
193 	case STATE2:
194 		dc->brk_state = STATE0;
195 		if (c == KEY_CTRLB) {
196 #if DCONS_FORCE_GDB
197 			if (dc->flags & DC_GDB)
198 				boothowto |= RB_GDB;
199 #endif
200 			breakpoint();
201 		}
202 	}
203 	if (c == KEY_CR)
204 		dc->brk_state = STATE1;
205 #endif
206 	return (c);
207 }
208 #else
209 #define	dcons_check_break(dc, c)	(c)
210 #endif
211 
212 static int
213 dcons_os_checkc(struct dcons_softc *dc)
214 {
215 	int c;
216 
217 	if (dg.dma_tag != NULL)
218 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_POSTREAD);
219 
220 	c = dcons_check_break(dc, dcons_checkc(dc));
221 
222 	if (dg.dma_tag != NULL)
223 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_PREREAD);
224 
225 	return (c);
226 }
227 
228 static int
229 dcons_os_getc(struct dcons_softc *dc)
230 {
231 	int c;
232 
233 	while ((c = dcons_os_checkc(dc)) == -1);
234 
235 	return (c & 0xff);
236 }
237 
238 static void
239 dcons_os_putc(struct dcons_softc *dc, int c)
240 {
241 	if (dg.dma_tag != NULL)
242 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_POSTWRITE);
243 
244 	dcons_putc(dc, c);
245 
246 	if (dg.dma_tag != NULL)
247 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_PREWRITE);
248 }
249 static int
250 dcons_open(struct dev_open_args *ap)
251 {
252 	cdev_t dev = ap->a_head.a_dev;
253 	struct tty *tp;
254 	int unit, error;
255 
256 	unit = minor(dev);
257 	if (unit != 0)
258 		return (ENXIO);
259 
260 	tp = dev->si_tty = ttymalloc(dev->si_tty);
261 	tp->t_oproc = dcons_tty_start;
262 	tp->t_param = dcons_tty_param;
263 	tp->t_stop = nottystop;
264 	tp->t_dev = dev;
265 
266 	error = 0;
267 
268 	crit_enter();
269 	if ((tp->t_state & TS_ISOPEN) == 0) {
270 		tp->t_state |= TS_CARR_ON;
271 		ttychars(tp);
272 		tp->t_iflag = TTYDEF_IFLAG;
273 		tp->t_oflag = TTYDEF_OFLAG;
274 		tp->t_cflag = TTYDEF_CFLAG|CLOCAL;
275 		tp->t_lflag = TTYDEF_LFLAG;
276 		tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
277 		ttsetwater(tp);
278 	} else if ((tp->t_state & TS_XCLUDE) && priv_check_cred(ap->a_cred, PRIV_ROOT, 0)) {
279 		crit_exit();
280 		return (EBUSY);
281 	}
282 	crit_exit();
283 
284 #if __FreeBSD_version < 502113
285 	error = (*linesw[tp->t_line].l_open)(dev, tp);
286 #else
287 	error = ttyld_open(tp, dev);
288 #endif
289 
290 	return (error);
291 }
292 
293 static int
294 dcons_close(struct dev_close_args *ap)
295 {
296 	cdev_t dev = ap->a_head.a_dev;
297 	int	unit;
298 	struct	tty *tp;
299 
300 	unit = minor(dev);
301 	if (unit != 0)
302 		return (ENXIO);
303 
304 	tp = dev->si_tty;
305 	if (tp->t_state & TS_ISOPEN) {
306 		(*linesw[tp->t_line].l_close)(tp, ap->a_fflag);
307 		ttyclose(tp);
308 	}
309 
310 	return (0);
311 }
312 
313 static int
314 dcons_ioctl(struct dev_ioctl_args *ap)
315 {
316 	cdev_t dev = ap->a_head.a_dev;
317 	int	unit;
318 	struct	tty *tp;
319 	int	error;
320 
321 	unit = minor(dev);
322 	if (unit != 0)
323 		return (ENXIO);
324 
325 	tp = dev->si_tty;
326 	error = (*linesw[tp->t_line].l_ioctl)(tp, ap->a_cmd, ap->a_data, ap->a_fflag, ap->a_cred);
327 	if (error != ENOIOCTL)
328 		return (error);
329 
330 	error = ttioctl(tp, ap->a_cmd, ap->a_data, ap->a_fflag);
331 	if (error != ENOIOCTL)
332 		return (error);
333 
334 	return (ENOTTY);
335 }
336 
337 static int
338 dcons_tty_param(struct tty *tp, struct termios *t)
339 {
340 	tp->t_ispeed = t->c_ispeed;
341 	tp->t_ospeed = t->c_ospeed;
342 	tp->t_cflag = t->c_cflag;
343 	return 0;
344 }
345 
346 static void
347 dcons_tty_start(struct tty *tp)
348 {
349 	struct dcons_softc *dc;
350 
351 	dc = (struct dcons_softc *)tp->t_dev->si_drv1;
352 	crit_enter();
353 	if (tp->t_state & (TS_TIMEOUT | TS_TTSTOP)) {
354 		ttwwakeup(tp);
355 		return;
356 	}
357 
358 	tp->t_state |= TS_BUSY;
359 	while (tp->t_outq.c_cc != 0)
360 		dcons_os_putc(dc, clist_getc(&tp->t_outq));
361 	tp->t_state &= ~TS_BUSY;
362 
363 	ttwwakeup(tp);
364 	crit_exit();
365 }
366 
367 static void
368 dcons_timeout(void *v)
369 {
370 	struct	tty *tp;
371 	struct dcons_softc *dc;
372 	int i, c, polltime;
373 
374 	for (i = 0; i < DCONS_NPORT; i ++) {
375 		dc = &sc[i];
376 		tp = ((DEV)dc->dev)->si_tty;
377 		while ((c = dcons_os_checkc(dc)) != -1)
378 			if (tp->t_state & TS_ISOPEN)
379 #if __FreeBSD_version < 502113
380 				(*linesw[tp->t_line].l_rint)(c, tp);
381 #else
382 				ttyld_rint(tp, c);
383 #endif
384 	}
385 	polltime = hz / poll_hz;
386 	if (polltime < 1)
387 		polltime = 1;
388 	callout_reset(&dcons_callout, polltime, dcons_timeout, tp);
389 }
390 
391 static void
392 dcons_cnprobe(struct consdev *cp)
393 {
394 #ifdef __DragonFly__
395 	cp->cn_probegood = 1;
396 #elif __FreeBSD_version >= 501109
397 	ksprintf(cp->cn_name, "dcons");
398 #else
399 	cp->cn_dev = makedev(CDEV_MAJOR, DCONS_CON);
400 #endif
401 #if DCONS_FORCE_CONSOLE
402 	cp->cn_pri = CN_REMOTE;
403 #else
404 	cp->cn_pri = CN_NORMAL;
405 #endif
406 }
407 
408 static void
409 dcons_cninit(struct consdev *cp)
410 {
411 	dcons_drv_init(0);
412 #if CONS_NODEV
413 	cp->cn_arg
414 #else
415 	cp->cn_private
416 #endif
417 		= (void *)&sc[DCONS_CON]; /* share port0 with unit0 */
418 }
419 
420 static void
421 dcons_cninit_fini(struct consdev *cp)
422 {
423 	cp->cn_dev = make_dev(&dcons_ops, DCONS_CON,
424 			      UID_ROOT, GID_WHEEL, 0600, "dcons");
425 }
426 
427 #if CONS_NODEV
428 static int
429 dcons_cngetc(struct consdev *cp)
430 {
431 	struct dcons_softc *dc = (struct dcons_softc *)cp->cn_arg;
432 	return (dcons_os_getc(dc));
433 }
434 static int
435 dcons_cncheckc(struct consdev *cp)
436 {
437 	struct dcons_softc *dc = (struct dcons_softc *)cp->cn_arg;
438 	return (dcons_os_checkc(dc));
439 }
440 static void
441 dcons_cnputc(struct consdev *cp, int c)
442 {
443 	struct dcons_softc *dc = (struct dcons_softc *)cp->cn_arg;
444 	dcons_os_putc(dc, c);
445 }
446 #else
447 static int
448 dcons_cngetc(void *private)
449 {
450 	struct dcons_softc *dc = (struct dcons_softc *)private;
451 	return (dcons_os_getc(dc));
452 }
453 static int
454 dcons_cncheckc(void *private)
455 {
456 	struct dcons_softc *dc = (struct dcons_softc *)private;
457 	return (dcons_os_checkc(dc));
458 }
459 static void
460 dcons_cnputc(void *private, int c)
461 {
462 	struct dcons_softc *dc = (struct dcons_softc *)private;
463 	dcons_os_putc(dc, c);
464 }
465 #endif
466 
467 static int
468 dcons_drv_init(int stage)
469 {
470 #ifdef __i386__
471 	quad_t addr, size;
472 #endif
473 
474 	if (drv_init)
475 		return(drv_init);
476 
477 	drv_init = -1;
478 
479 	bzero(&dg, sizeof(dg));
480 	dcons_conf = &dg;
481 	dg.cdev = &dcons_consdev;
482 	dg.buf = NULL;
483 	dg.size = DCONS_BUF_SIZE;
484 
485 #ifdef __i386__
486 	if (kgetenv_quad("dcons.addr", &addr) > 0 &&
487 	    kgetenv_quad("dcons.size", &size) > 0) {
488 		vm_paddr_t pa;
489 		/*
490 		 * Allow read/write access to dcons buffer.
491 		 */
492 		for (pa = trunc_page(addr); pa < addr + size; pa += PAGE_SIZE)
493 			pmap_kmodify_rw((vm_offset_t)(KERNBASE + pa));
494 		cpu_invltlb();
495 		/* XXX P to V */
496 		dg.buf = (struct dcons_buf *)(vm_offset_t)(KERNBASE + addr);
497 		dg.size = size;
498 		if (dcons_load_buffer(dg.buf, dg.size, sc) < 0)
499 			dg.buf = NULL;
500 	}
501 #endif
502 	if (dg.buf != NULL)
503 		goto ok;
504 
505 #ifndef KLD_MODULE
506 	if (stage == 0) { /* XXX or cold */
507 		/*
508 		 * DCONS_FORCE_CONSOLE == 1 and statically linked.
509 		 * called from cninit(). can't use contigmalloc yet .
510 		 */
511 		dg.buf = (struct dcons_buf *) bssbuf;
512 		dcons_init(dg.buf, dg.size, sc);
513 	} else
514 #endif
515 	{
516 		/*
517 		 * DCONS_FORCE_CONSOLE == 0 or kernel module case.
518 		 * if the module is loaded after boot,
519 		 * bssbuf could be non-continuous.
520 		 */
521 		dg.buf = (struct dcons_buf *) contigmalloc(dg.size,
522 			M_DEVBUF, 0, 0x10000, 0xffffffff, PAGE_SIZE, 0ul);
523 		dcons_init(dg.buf, dg.size, sc);
524 	}
525 
526 ok:
527 	dcons_buf = dg.buf;
528 
529 #if DDB && DCONS_FORCE_GDB
530 	if (gdb_tab == NULL) {
531 		gdb_tab = &dcons_consdev;
532 		dcons_consdev.cn_gdbprivate = &sc[DCONS_GDB];
533 	}
534 #endif
535 	drv_init = 1;
536 
537 	return 0;
538 }
539 
540 
541 static int
542 dcons_attach_port(int port, char *name, int flags)
543 {
544 	struct dcons_softc *dc;
545 	struct tty *tp;
546 	DEV dev;
547 
548 	dc = &sc[port];
549 	dc->flags = flags;
550 	dev = make_dev(&dcons_ops, port,
551 			UID_ROOT, GID_WHEEL, 0600, name);
552 	dc->dev = (void *)dev;
553 	tp = ttymalloc(NULL);
554 
555 	dev->si_drv1 = (void *)dc;
556 	dev->si_tty = tp;
557 
558 	tp->t_oproc = dcons_tty_start;
559 	tp->t_param = dcons_tty_param;
560 	tp->t_stop = nottystop;
561 	tp->t_dev = dc->dev;
562 
563 	return(0);
564 }
565 
566 static int
567 dcons_attach(void)
568 {
569 	int polltime;
570 
571 	dcons_attach_port(DCONS_CON, "dcons", 0);
572 	dcons_attach_port(DCONS_GDB, "dgdb", DC_GDB);
573 #if __FreeBSD_version < 500000
574 	callout_init(&dcons_callout);
575 #else
576 	callout_init(&dcons_callout, 0);
577 #endif
578 	polltime = hz / poll_hz;
579 	if (polltime < 1)
580 		polltime = 1;
581 	callout_reset(&dcons_callout, polltime, dcons_timeout, NULL);
582 	return(0);
583 }
584 
585 static int
586 dcons_detach(int port)
587 {
588 	struct	tty *tp;
589 	struct dcons_softc *dc;
590 
591 	dc = &sc[port];
592 
593 	tp = ((DEV)dc->dev)->si_tty;
594 
595 	if (tp->t_state & TS_ISOPEN) {
596 		kprintf("dcons: still opened\n");
597 #if __FreeBSD_version < 502113
598 		(*linesw[tp->t_line].l_close)(tp, 0);
599 		ttyclose(tp);
600 #else
601 		ttyld_close(tp, 0);
602 		tty_close(tp);
603 #endif
604 	}
605 	/* XXX
606 	 * must wait until all device are closed.
607 	 */
608 #ifdef __DragonFly__
609 	tsleep((void *)dc, 0, "dcodtc", hz/4);
610 #else
611 	tsleep((void *)dc, PWAIT, "dcodtc", hz/4);
612 #endif
613 	destroy_dev(dc->dev);
614 
615 	return(0);
616 }
617 
618 
619 /* cnXXX works only for FreeBSD-5 */
620 static int
621 dcons_modevent(module_t mode, int type, void *data)
622 {
623 	int err = 0, ret;
624 
625 	switch (type) {
626 	case MOD_LOAD:
627 		ret = dcons_drv_init(1);
628 		dcons_attach();
629 #if __FreeBSD_version >= 500000
630 		if (ret == 0) {
631 			dcons_cnprobe(&dcons_consdev);
632 			dcons_cninit(&dcons_consdev);
633 			cnadd(&dcons_consdev);
634 		}
635 #endif
636 		break;
637 	case MOD_UNLOAD:
638 		kprintf("dcons: unload\n");
639 		callout_stop(&dcons_callout);
640 #if __FreeBSD_version < 502122
641 #if DDB && DCONS_FORCE_GDB
642 #if CONS_NODEV
643 		gdb_arg = NULL;
644 #else
645 		if (gdb_tab == &dcons_consdev)
646 			gdb_tab = NULL;
647 #endif
648 #endif
649 #endif
650 #if __FreeBSD_version >= 500000
651 		cnremove(&dcons_consdev);
652 #endif
653 		dcons_detach(DCONS_CON);
654 		dcons_detach(DCONS_GDB);
655 		dg.buf->magic = 0;
656 
657 		contigfree(dg.buf, DCONS_BUF_SIZE, M_DEVBUF);
658 
659 		break;
660 	case MOD_SHUTDOWN:
661 		dg.buf->magic = 0;
662 		break;
663 	default:
664 		err = EOPNOTSUPP;
665 		break;
666 	}
667 	return(err);
668 }
669 
670 #if __FreeBSD_version >= 502122
671 /* Debugger interface */
672 
673 static int
674 dcons_dbg_probe(void)
675 {
676 	return(DCONS_FORCE_GDB);
677 }
678 
679 static void
680 dcons_dbg_init(void)
681 {
682 }
683 
684 static void
685 dcons_dbg_term(void)
686 {
687 }
688 
689 static void
690 dcons_dbg_putc(int c)
691 {
692 	struct dcons_softc *dc = &sc[DCONS_GDB];
693 	dcons_os_putc(dc, c);
694 }
695 
696 static int
697 dcons_dbg_checkc(void)
698 {
699 	struct dcons_softc *dc = &sc[DCONS_GDB];
700 	return (dcons_os_checkc(dc));
701 }
702 
703 static int
704 dcons_dbg_getc(void)
705 {
706 	struct dcons_softc *dc = &sc[DCONS_GDB];
707 	return (dcons_os_getc(dc));
708 }
709 #endif
710 
711 DEV_MODULE(dcons, dcons_modevent, NULL);
712 MODULE_VERSION(dcons, DCONS_VERSION);
713