xref: /freebsd/sys/dev/dcons/dcons_os.c (revision 6af83ee0d2941d18880b6aaa2b4facd1d30c6106)
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  * $FreeBSD$
35  */
36 
37 #include <sys/param.h>
38 #if __FreeBSD_version >= 502122
39 #include <sys/kdb.h>
40 #include <gdb/gdb.h>
41 #endif
42 #include <sys/kernel.h>
43 #include <sys/module.h>
44 #include <sys/systm.h>
45 #include <sys/types.h>
46 #include <sys/conf.h>
47 #include <sys/cons.h>
48 #include <sys/consio.h>
49 #include <sys/tty.h>
50 #include <sys/malloc.h>
51 #include <sys/proc.h>
52 #include <sys/ucred.h>
53 
54 #include <machine/bus.h>
55 
56 #ifdef __DragonFly__
57 #include "dcons.h"
58 #include "dcons_os.h"
59 #else
60 #include <dev/dcons/dcons.h>
61 #include <dev/dcons/dcons_os.h>
62 #endif
63 
64 #include <ddb/ddb.h>
65 #include <sys/reboot.h>
66 
67 #include <sys/sysctl.h>
68 
69 #include <vm/vm.h>
70 #include <vm/vm_param.h>
71 #include <vm/pmap.h>
72 
73 #include "opt_ddb.h"
74 #include "opt_comconsole.h"
75 #include "opt_dcons.h"
76 
77 #ifndef DCONS_POLL_HZ
78 #define DCONS_POLL_HZ	100
79 #endif
80 
81 #ifndef DCONS_BUF_SIZE
82 #define DCONS_BUF_SIZE (16*1024)
83 #endif
84 
85 #ifndef DCONS_FORCE_CONSOLE
86 #define DCONS_FORCE_CONSOLE	0	/* Mostly for FreeBSD-4/DragonFly */
87 #endif
88 
89 #ifndef DCONS_FORCE_GDB
90 #define DCONS_FORCE_GDB	1
91 #endif
92 
93 #if __FreeBSD_version >= 500101
94 #define CONS_NODEV	1
95 #if __FreeBSD_version < 502122
96 static struct consdev gdbconsdev;
97 #endif
98 #endif
99 
100 static d_open_t		dcons_open;
101 static d_close_t	dcons_close;
102 #if defined(__DragonFly__) || __FreeBSD_version < 500104
103 static d_ioctl_t	dcons_ioctl;
104 #endif
105 
106 static struct cdevsw dcons_cdevsw = {
107 #ifdef __DragonFly__
108 #define CDEV_MAJOR      184
109 	"dcons", CDEV_MAJOR, D_TTY, NULL, 0,
110 	dcons_open, dcons_close, ttyread, ttywrite, dcons_ioctl,
111 	ttypoll, nommap, nostrategy, nodump, nopsize,
112 #elif __FreeBSD_version >= 500104
113 	.d_version =	D_VERSION,
114 	.d_open =	dcons_open,
115 	.d_close =	dcons_close,
116 	.d_name =	"dcons",
117 	.d_flags =	D_TTY | D_NEEDGIANT,
118 #else
119 #define CDEV_MAJOR      184
120 	/* open */	dcons_open,
121 	/* close */	dcons_close,
122 	/* read */	ttyread,
123 	/* write */	ttywrite,
124 	/* ioctl */	dcons_ioctl,
125 	/* poll */	ttypoll,
126 	/* mmap */	nommap,
127 	/* strategy */	nostrategy,
128 	/* name */	"dcons",
129 	/* major */	CDEV_MAJOR,
130 	/* dump */	nodump,
131 	/* psize */	nopsize,
132 	/* flags */	D_TTY,
133 #endif
134 };
135 
136 #ifndef KLD_MODULE
137 static char bssbuf[DCONS_BUF_SIZE];	/* buf in bss */
138 #endif
139 
140 /* global data */
141 static struct dcons_global dg;
142 struct dcons_global *dcons_conf;
143 static int poll_hz = DCONS_POLL_HZ;
144 
145 static struct dcons_softc sc[DCONS_NPORT];
146 
147 SYSCTL_NODE(_kern, OID_AUTO, dcons, CTLFLAG_RD, 0, "Dumb Console");
148 SYSCTL_INT(_kern_dcons, OID_AUTO, poll_hz, CTLFLAG_RW, &poll_hz, 0,
149 				"dcons polling rate");
150 
151 static int drv_init = 0;
152 static struct callout dcons_callout;
153 struct dcons_buf *dcons_buf;		/* for local dconschat */
154 
155 #ifdef __DragonFly__
156 #define DEV	dev_t
157 #define THREAD	d_thread_t
158 #elif __FreeBSD_version < 500000
159 #define DEV	dev_t
160 #define THREAD	struct proc
161 #else
162 #define DEV	struct cdev *
163 #define THREAD	struct thread
164 #endif
165 
166 
167 static void	dcons_tty_start(struct tty *);
168 static int	dcons_tty_param(struct tty *, struct termios *);
169 static void	dcons_timeout(void *);
170 static int	dcons_drv_init(int);
171 
172 static cn_probe_t	dcons_cnprobe;
173 static cn_init_t	dcons_cninit;
174 static cn_getc_t	dcons_cngetc;
175 static cn_checkc_t 	dcons_cncheckc;
176 static cn_putc_t	dcons_cnputc;
177 
178 CONS_DRIVER(dcons, dcons_cnprobe, dcons_cninit, NULL, dcons_cngetc,
179     dcons_cncheckc, dcons_cnputc, NULL);
180 
181 #if __FreeBSD_version >= 502122
182 static gdb_probe_f dcons_dbg_probe;
183 static gdb_init_f dcons_dbg_init;
184 static gdb_term_f dcons_dbg_term;
185 static gdb_getc_f dcons_dbg_getc;
186 static gdb_checkc_f dcons_dbg_checkc;
187 static gdb_putc_f dcons_dbg_putc;
188 
189 GDB_DBGPORT(dcons, dcons_dbg_probe, dcons_dbg_init, dcons_dbg_term,
190     dcons_dbg_checkc, dcons_dbg_getc, dcons_dbg_putc);
191 
192 extern struct gdb_dbgport *gdb_cur;
193 #endif
194 
195 #if (KDB || DDB) && ALT_BREAK_TO_DEBUGGER
196 static int
197 dcons_check_break(struct dcons_softc *dc, int c)
198 {
199 	if (c < 0)
200 		return (c);
201 
202 #if __FreeBSD_version >= 502122
203 	if (kdb_alt_break(c, &dc->brk_state)) {
204 		if ((dc->flags & DC_GDB) != 0) {
205 			if (gdb_cur == &dcons_gdb_dbgport) {
206 				kdb_dbbe_select("gdb");
207 				breakpoint();
208 			}
209 		} else
210 			breakpoint();
211 	}
212 #else
213 	switch (dc->brk_state) {
214 	case STATE1:
215 		if (c == KEY_TILDE)
216 			dc->brk_state = STATE2;
217 		else
218 			dc->brk_state = STATE0;
219 		break;
220 	case STATE2:
221 		dc->brk_state = STATE0;
222 		if (c == KEY_CTRLB) {
223 #if DCONS_FORCE_GDB
224 			if (dc->flags & DC_GDB)
225 				boothowto |= RB_GDB;
226 #endif
227 			breakpoint();
228 		}
229 	}
230 	if (c == KEY_CR)
231 		dc->brk_state = STATE1;
232 #endif
233 	return (c);
234 }
235 #else
236 #define	dcons_check_break(dc, c)	(c)
237 #endif
238 
239 static int
240 dcons_os_checkc(struct dcons_softc *dc)
241 {
242 	int c;
243 
244 	if (dg.dma_tag != NULL)
245 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_POSTREAD);
246 
247 	c = dcons_check_break(dc, dcons_checkc(dc));
248 
249 	if (dg.dma_tag != NULL)
250 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_PREREAD);
251 
252 	return (c);
253 }
254 
255 static int
256 dcons_os_getc(struct dcons_softc *dc)
257 {
258 	int c;
259 
260 	while ((c = dcons_os_checkc(dc)) == -1);
261 
262 	return (c & 0xff);
263 }
264 
265 static void
266 dcons_os_putc(struct dcons_softc *dc, int c)
267 {
268 	if (dg.dma_tag != NULL)
269 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_POSTWRITE);
270 
271 	dcons_putc(dc, c);
272 
273 	if (dg.dma_tag != NULL)
274 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_PREWRITE);
275 }
276 static int
277 dcons_open(DEV dev, int flag, int mode, THREAD *td)
278 {
279 	struct tty *tp;
280 	int unit, error, s;
281 
282 	unit = minor(dev);
283 	if (unit != 0)
284 		return (ENXIO);
285 
286 	tp = dev->si_tty = ttymalloc(dev->si_tty);
287 	tp->t_oproc = dcons_tty_start;
288 	tp->t_param = dcons_tty_param;
289 	tp->t_stop = nottystop;
290 	tp->t_dev = dev;
291 
292 	error = 0;
293 
294 	s = spltty();
295 	if ((tp->t_state & TS_ISOPEN) == 0) {
296 		tp->t_state |= TS_CARR_ON;
297 		ttyconsolemode(tp, 0);
298 		ttsetwater(tp);
299 	} else if ((tp->t_state & TS_XCLUDE) && suser(td)) {
300 		splx(s);
301 		return (EBUSY);
302 	}
303 	splx(s);
304 
305 #if __FreeBSD_version < 502113
306 	error = (*linesw[tp->t_line].l_open)(dev, tp);
307 #else
308 	error = ttyld_open(tp, dev);
309 #endif
310 
311 	return (error);
312 }
313 
314 static int
315 dcons_close(DEV dev, int flag, int mode, THREAD *td)
316 {
317 	int	unit;
318 	struct	tty *tp;
319 
320 	unit = minor(dev);
321 	if (unit != 0)
322 		return (ENXIO);
323 
324 	tp = dev->si_tty;
325 	if (tp->t_state & TS_ISOPEN) {
326 #if __FreeBSD_version < 502113
327 		(*linesw[tp->t_line].l_close)(tp, flag);
328 		ttyclose(tp);
329 #else
330 		ttyld_close(tp, flag);
331 		tty_close(tp);
332 #endif
333 	}
334 
335 	return (0);
336 }
337 
338 #if defined(__DragonFly__) || __FreeBSD_version < 500104
339 static int
340 dcons_ioctl(DEV dev, u_long cmd, caddr_t data, int flag, THREAD *td)
341 {
342 	int	unit;
343 	struct	tty *tp;
344 	int	error;
345 
346 	unit = minor(dev);
347 	if (unit != 0)
348 		return (ENXIO);
349 
350 	tp = dev->si_tty;
351 	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, td);
352 	if (error != ENOIOCTL)
353 		return (error);
354 
355 	error = ttioctl(tp, cmd, data, flag);
356 	if (error != ENOIOCTL)
357 		return (error);
358 
359 	return (ENOTTY);
360 }
361 #endif
362 
363 static int
364 dcons_tty_param(struct tty *tp, struct termios *t)
365 {
366 	tp->t_ispeed = t->c_ispeed;
367 	tp->t_ospeed = t->c_ospeed;
368 	tp->t_cflag = t->c_cflag;
369 	return 0;
370 }
371 
372 static void
373 dcons_tty_start(struct tty *tp)
374 {
375 	struct dcons_softc *dc;
376 	int s;
377 
378 	dc = (struct dcons_softc *)tp->t_dev->si_drv1;
379 	s = spltty();
380 	if (tp->t_state & (TS_TIMEOUT | TS_TTSTOP)) {
381 		ttwwakeup(tp);
382 		return;
383 	}
384 
385 	tp->t_state |= TS_BUSY;
386 	while (tp->t_outq.c_cc != 0)
387 		dcons_os_putc(dc, getc(&tp->t_outq));
388 	tp->t_state &= ~TS_BUSY;
389 
390 	ttwwakeup(tp);
391 	splx(s);
392 }
393 
394 static void
395 dcons_timeout(void *v)
396 {
397 	struct	tty *tp;
398 	struct dcons_softc *dc;
399 	int i, c, polltime;
400 
401 	for (i = 0; i < DCONS_NPORT; i ++) {
402 		dc = &sc[i];
403 		tp = ((DEV)dc->dev)->si_tty;
404 		while ((c = dcons_os_checkc(dc)) != -1)
405 			if (tp->t_state & TS_ISOPEN)
406 #if __FreeBSD_version < 502113
407 				(*linesw[tp->t_line].l_rint)(c, tp);
408 #else
409 				ttyld_rint(tp, c);
410 #endif
411 	}
412 	polltime = hz / poll_hz;
413 	if (polltime < 1)
414 		polltime = 1;
415 	callout_reset(&dcons_callout, polltime, dcons_timeout, tp);
416 }
417 
418 static void
419 dcons_cnprobe(struct consdev *cp)
420 {
421 #ifdef __DragonFly__
422 	cp->cn_dev = make_dev(&dcons_cdevsw, DCONS_CON,
423 	    UID_ROOT, GID_WHEEL, 0600, "dcons");
424 #elif __FreeBSD_version >= 501109
425 	sprintf(cp->cn_name, "dcons");
426 #else
427 	cp->cn_dev = makedev(CDEV_MAJOR, DCONS_CON);
428 #endif
429 #if DCONS_FORCE_CONSOLE
430 	cp->cn_pri = CN_REMOTE;
431 #else
432 	cp->cn_pri = CN_NORMAL;
433 #endif
434 }
435 
436 static void
437 dcons_cninit(struct consdev *cp)
438 {
439 	dcons_drv_init(0);
440 #if CONS_NODEV
441 	cp->cn_arg
442 #else
443 	cp->cn_dev->si_drv1
444 #endif
445 		= (void *)&sc[DCONS_CON]; /* share port0 with unit0 */
446 }
447 
448 #if CONS_NODEV
449 static int
450 dcons_cngetc(struct consdev *cp)
451 {
452 	struct dcons_softc *dc = (struct dcons_softc *)cp->cn_arg;
453 	return (dcons_os_getc(dc));
454 }
455 static int
456 dcons_cncheckc(struct consdev *cp)
457 {
458 	struct dcons_softc *dc = (struct dcons_softc *)cp->cn_arg;
459 	return (dcons_os_checkc(dc));
460 }
461 static void
462 dcons_cnputc(struct consdev *cp, int c)
463 {
464 	struct dcons_softc *dc = (struct dcons_softc *)cp->cn_arg;
465 	dcons_os_putc(dc, c);
466 }
467 #else
468 static int
469 dcons_cngetc(DEV dev)
470 {
471 	struct dcons_softc *dc = (struct dcons_softc *)dev->si_drv1;
472 	return (dcons_os_getc(dc));
473 }
474 static int
475 dcons_cncheckc(DEV dev)
476 {
477 	struct dcons_softc *dc = (struct dcons_softc *)dev->si_drv1;
478 	return (dcons_os_checkc(dc));
479 }
480 static void
481 dcons_cnputc(DEV dev, int c)
482 {
483 	struct dcons_softc *dc = (struct dcons_softc *)dev->si_drv1;
484 	dcons_os_putc(dc, c);
485 }
486 #endif
487 
488 static int
489 dcons_drv_init(int stage)
490 {
491 #if defined(__i386__) || defined(__amd64__)
492 	quad_t addr, size;
493 #endif
494 
495 	if (drv_init)
496 		return(drv_init);
497 
498 	drv_init = -1;
499 
500 	bzero(&dg, sizeof(dg));
501 	dcons_conf = &dg;
502 	dg.cdev = &dcons_consdev;
503 	dg.buf = NULL;
504 	dg.size = DCONS_BUF_SIZE;
505 
506 #if defined(__i386__) || defined(__amd64__)
507 	if (getenv_quad("dcons.addr", &addr) > 0 &&
508 	    getenv_quad("dcons.size", &size) > 0) {
509 #ifdef __i386__
510 		vm_paddr_t pa;
511 		/*
512 		 * Allow read/write access to dcons buffer.
513 		 */
514 		for (pa = trunc_page(addr); pa < addr + size; pa += PAGE_SIZE)
515 			*vtopte(KERNBASE + pa) |= PG_RW;
516 		invltlb();
517 #endif
518 		/* XXX P to V */
519 		dg.buf = (struct dcons_buf *)(vm_offset_t)(KERNBASE + addr);
520 		dg.size = size;
521 		if (dcons_load_buffer(dg.buf, dg.size, sc) < 0)
522 			dg.buf = NULL;
523 	}
524 #endif
525 	if (dg.buf != NULL)
526 		goto ok;
527 
528 #ifndef KLD_MODULE
529 	if (stage == 0) { /* XXX or cold */
530 		/*
531 		 * DCONS_FORCE_CONSOLE == 1 and statically linked.
532 		 * called from cninit(). can't use contigmalloc yet .
533 		 */
534 		dg.buf = (struct dcons_buf *) bssbuf;
535 		dcons_init(dg.buf, dg.size, sc);
536 	} else
537 #endif
538 	{
539 		/*
540 		 * DCONS_FORCE_CONSOLE == 0 or kernel module case.
541 		 * if the module is loaded after boot,
542 		 * bssbuf could be non-continuous.
543 		 */
544 		dg.buf = (struct dcons_buf *) contigmalloc(dg.size,
545 			M_DEVBUF, 0, 0x10000, 0xffffffff, PAGE_SIZE, 0ul);
546 		dcons_init(dg.buf, dg.size, sc);
547 	}
548 
549 ok:
550 	dcons_buf = dg.buf;
551 
552 #if __FreeBSD_version < 502122
553 #if DDB && DCONS_FORCE_GDB
554 #if CONS_NODEV
555 	gdbconsdev.cn_arg = (void *)&sc[DCONS_GDB];
556 #if __FreeBSD_version >= 501109
557 	sprintf(gdbconsdev.cn_name, "dgdb");
558 #endif
559 	gdb_arg = &gdbconsdev;
560 #elif defined(__DragonFly__)
561 	gdbdev = make_dev(&dcons_cdevsw, DCONS_GDB,
562 	    UID_ROOT, GID_WHEEL, 0600, "dgdb");
563 #else
564 	gdbdev = makedev(CDEV_MAJOR, DCONS_GDB);
565 #endif
566 	gdb_getc = dcons_cngetc;
567 	gdb_putc = dcons_cnputc;
568 #endif
569 #endif
570 	drv_init = 1;
571 
572 	return 0;
573 }
574 
575 
576 static int
577 dcons_attach_port(int port, char *name, int flags)
578 {
579 	struct dcons_softc *dc;
580 	struct tty *tp;
581 	DEV dev;
582 
583 	dc = &sc[port];
584 	dc->flags = flags;
585 	dev = make_dev(&dcons_cdevsw, port,
586 			UID_ROOT, GID_WHEEL, 0600, name);
587 	dc->dev = (void *)dev;
588 	tp = ttymalloc(NULL);
589 
590 	dev->si_drv1 = (void *)dc;
591 	dev->si_tty = tp;
592 
593 	tp->t_oproc = dcons_tty_start;
594 	tp->t_param = dcons_tty_param;
595 	tp->t_stop = nottystop;
596 	tp->t_dev = dc->dev;
597 
598 	return(0);
599 }
600 
601 static int
602 dcons_attach(void)
603 {
604 	int polltime;
605 
606 #ifdef __DragonFly__
607 	cdevsw_add(&dcons_cdevsw, -1, 0);
608 #endif
609 	dcons_attach_port(DCONS_CON, "dcons", 0);
610 	dcons_attach_port(DCONS_GDB, "dgdb", DC_GDB);
611 #if __FreeBSD_version < 500000
612 	callout_init(&dcons_callout);
613 #else
614 	callout_init(&dcons_callout, 0);
615 #endif
616 	polltime = hz / poll_hz;
617 	if (polltime < 1)
618 		polltime = 1;
619 	callout_reset(&dcons_callout, polltime, dcons_timeout, NULL);
620 	return(0);
621 }
622 
623 static int
624 dcons_detach(int port)
625 {
626 	struct	tty *tp;
627 	struct dcons_softc *dc;
628 
629 	dc = &sc[port];
630 
631 	tp = ((DEV)dc->dev)->si_tty;
632 
633 	if (tp->t_state & TS_ISOPEN) {
634 		printf("dcons: still opened\n");
635 #if __FreeBSD_version < 502113
636 		(*linesw[tp->t_line].l_close)(tp, 0);
637 		tp->t_gen++;
638 		ttyclose(tp);
639 		ttwakeup(tp);
640 		ttwwakeup(tp);
641 #else
642 		ttyld_close(tp, 0);
643 		tty_close(tp);
644 #endif
645 	}
646 	/* XXX
647 	 * must wait until all device are closed.
648 	 */
649 #ifdef __DragonFly__
650 	tsleep((void *)dc, 0, "dcodtc", hz/4);
651 #else
652 	tsleep((void *)dc, PWAIT, "dcodtc", hz/4);
653 #endif
654 	destroy_dev(dc->dev);
655 
656 	return(0);
657 }
658 
659 
660 /* cnXXX works only for FreeBSD-5 */
661 static int
662 dcons_modevent(module_t mode, int type, void *data)
663 {
664 	int err = 0, ret;
665 
666 	switch (type) {
667 	case MOD_LOAD:
668 		ret = dcons_drv_init(1);
669 		dcons_attach();
670 #if __FreeBSD_version >= 500000
671 		if (ret == 0) {
672 			dcons_cnprobe(&dcons_consdev);
673 			dcons_cninit(&dcons_consdev);
674 			cnadd(&dcons_consdev);
675 		}
676 #endif
677 		break;
678 	case MOD_UNLOAD:
679 		printf("dcons: unload\n");
680 		callout_stop(&dcons_callout);
681 #if __FreeBSD_version < 502122
682 #if DDB && DCONS_FORCE_GDB
683 #if CONS_NODEV
684 		gdb_arg = NULL;
685 #else
686 		gdbdev = NULL;
687 #endif
688 #endif
689 #endif
690 #if __FreeBSD_version >= 500000
691 		cnremove(&dcons_consdev);
692 #endif
693 		dcons_detach(DCONS_CON);
694 		dcons_detach(DCONS_GDB);
695 		dg.buf->magic = 0;
696 
697 		contigfree(dg.buf, DCONS_BUF_SIZE, M_DEVBUF);
698 
699 		break;
700 	case MOD_SHUTDOWN:
701 		dg.buf->magic = 0;
702 		break;
703 	default:
704 		err = EOPNOTSUPP;
705 		break;
706 	}
707 	return(err);
708 }
709 
710 #if __FreeBSD_version >= 502122
711 /* Debugger interface */
712 
713 static int
714 dcons_dbg_probe(void)
715 {
716 	return(DCONS_FORCE_GDB);
717 }
718 
719 static void
720 dcons_dbg_init(void)
721 {
722 }
723 
724 static void
725 dcons_dbg_term(void)
726 {
727 }
728 
729 static void
730 dcons_dbg_putc(int c)
731 {
732 	struct dcons_softc *dc = &sc[DCONS_GDB];
733 	dcons_os_putc(dc, c);
734 }
735 
736 static int
737 dcons_dbg_checkc(void)
738 {
739 	struct dcons_softc *dc = &sc[DCONS_GDB];
740 	return (dcons_os_checkc(dc));
741 }
742 
743 static int
744 dcons_dbg_getc(void)
745 {
746 	struct dcons_softc *dc = &sc[DCONS_GDB];
747 	return (dcons_os_getc(dc));
748 }
749 #endif
750 
751 DEV_MODULE(dcons, dcons_modevent, NULL);
752 MODULE_VERSION(dcons, DCONS_VERSION);
753