xref: /freebsd/sys/dev/dcons/dcons_os.c (revision 0c927cdd8e6e05387fc5a9ffcb5dbe128d4ad749)
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/priv.h>
52 #include <sys/proc.h>
53 #include <sys/ucred.h>
54 
55 #include <machine/bus.h>
56 
57 #ifdef __DragonFly__
58 #include "dcons.h"
59 #include "dcons_os.h"
60 #else
61 #include <dev/dcons/dcons.h>
62 #include <dev/dcons/dcons_os.h>
63 #endif
64 
65 #include <ddb/ddb.h>
66 #include <sys/reboot.h>
67 
68 #include <sys/sysctl.h>
69 
70 #include <vm/vm.h>
71 #include <vm/vm_param.h>
72 #include <vm/pmap.h>
73 
74 #include "opt_comconsole.h"
75 #include "opt_dcons.h"
76 #include "opt_kdb.h"
77 #include "opt_gdb.h"
78 #include "opt_ddb.h"
79 
80 
81 #ifndef DCONS_POLL_HZ
82 #define DCONS_POLL_HZ	100
83 #endif
84 
85 #ifndef DCONS_BUF_SIZE
86 #define DCONS_BUF_SIZE (16*1024)
87 #endif
88 
89 #ifndef DCONS_FORCE_CONSOLE
90 #define DCONS_FORCE_CONSOLE	0	/* Mostly for FreeBSD-4/DragonFly */
91 #endif
92 
93 #ifndef DCONS_FORCE_GDB
94 #define DCONS_FORCE_GDB	1
95 #endif
96 
97 #if __FreeBSD_version >= 500101
98 #define CONS_NODEV	1
99 #if __FreeBSD_version < 502122
100 static struct consdev gdbconsdev;
101 #endif
102 #endif
103 
104 static d_open_t		dcons_open;
105 static d_close_t	dcons_close;
106 #if defined(__DragonFly__) || __FreeBSD_version < 500104
107 static d_ioctl_t	dcons_ioctl;
108 #endif
109 
110 static struct cdevsw dcons_cdevsw = {
111 #ifdef __DragonFly__
112 #define CDEV_MAJOR      184
113 	"dcons", CDEV_MAJOR, D_TTY, NULL, 0,
114 	dcons_open, dcons_close, ttyread, ttywrite, dcons_ioctl,
115 	ttypoll, nommap, nostrategy, nodump, nopsize,
116 #elif __FreeBSD_version >= 500104
117 	.d_version =	D_VERSION,
118 	.d_open =	dcons_open,
119 	.d_close =	dcons_close,
120 	.d_name =	"dcons",
121 	.d_flags =	D_TTY | D_NEEDGIANT,
122 #else
123 #define CDEV_MAJOR      184
124 	/* open */	dcons_open,
125 	/* close */	dcons_close,
126 	/* read */	ttyread,
127 	/* write */	ttywrite,
128 	/* ioctl */	dcons_ioctl,
129 	/* poll */	ttypoll,
130 	/* mmap */	nommap,
131 	/* strategy */	nostrategy,
132 	/* name */	"dcons",
133 	/* major */	CDEV_MAJOR,
134 	/* dump */	nodump,
135 	/* psize */	nopsize,
136 	/* flags */	D_TTY,
137 #endif
138 };
139 
140 #ifndef KLD_MODULE
141 static char bssbuf[DCONS_BUF_SIZE];	/* buf in bss */
142 #endif
143 
144 /* global data */
145 static struct dcons_global dg;
146 struct dcons_global *dcons_conf;
147 static int poll_hz = DCONS_POLL_HZ;
148 
149 static struct dcons_softc sc[DCONS_NPORT];
150 
151 SYSCTL_NODE(_kern, OID_AUTO, dcons, CTLFLAG_RD, 0, "Dumb Console");
152 SYSCTL_INT(_kern_dcons, OID_AUTO, poll_hz, CTLFLAG_RW, &poll_hz, 0,
153 				"dcons polling rate");
154 
155 static int drv_init = 0;
156 static struct callout dcons_callout;
157 struct dcons_buf *dcons_buf;		/* for local dconschat */
158 
159 #ifdef __DragonFly__
160 #define DEV	dev_t
161 #define THREAD	d_thread_t
162 #elif __FreeBSD_version < 500000
163 #define DEV	dev_t
164 #define THREAD	struct proc
165 #else
166 #define DEV	struct cdev *
167 #define THREAD	struct thread
168 #endif
169 
170 
171 static void	dcons_tty_start(struct tty *);
172 static int	dcons_tty_param(struct tty *, struct termios *);
173 static void	dcons_timeout(void *);
174 static int	dcons_drv_init(int);
175 
176 static cn_probe_t	dcons_cnprobe;
177 static cn_init_t	dcons_cninit;
178 static cn_term_t	dcons_cnterm;
179 static cn_getc_t	dcons_cngetc;
180 static cn_putc_t	dcons_cnputc;
181 
182 CONSOLE_DRIVER(dcons);
183 
184 #if defined(GDB) && (__FreeBSD_version >= 502122)
185 static gdb_probe_f dcons_dbg_probe;
186 static gdb_init_f dcons_dbg_init;
187 static gdb_term_f dcons_dbg_term;
188 static gdb_getc_f dcons_dbg_getc;
189 static gdb_putc_f dcons_dbg_putc;
190 
191 GDB_DBGPORT(dcons, dcons_dbg_probe, dcons_dbg_init, dcons_dbg_term,
192     dcons_dbg_getc, dcons_dbg_putc);
193 
194 extern struct gdb_dbgport *gdb_cur;
195 #endif
196 
197 #if (defined(GDB) || defined(DDB)) && defined(ALT_BREAK_TO_DEBUGGER)
198 static int
199 dcons_check_break(struct dcons_softc *dc, int c)
200 {
201 	if (c < 0)
202 		return (c);
203 
204 #if __FreeBSD_version >= 502122
205 	if (kdb_alt_break(c, &dc->brk_state)) {
206 		if ((dc->flags & DC_GDB) != 0) {
207 #ifdef GDB
208 			if (gdb_cur == &dcons_gdb_dbgport) {
209 				kdb_dbbe_select("gdb");
210 				kdb_enter("Break sequence on dcons gdb port");
211 			}
212 #endif
213 		} else
214 			kdb_enter("Break sequence on dcons console port");
215 	}
216 #else
217 	switch (dc->brk_state) {
218 	case STATE1:
219 		if (c == KEY_TILDE)
220 			dc->brk_state = STATE2;
221 		else
222 			dc->brk_state = STATE0;
223 		break;
224 	case STATE2:
225 		dc->brk_state = STATE0;
226 		if (c == KEY_CTRLB) {
227 #if DCONS_FORCE_GDB
228 			if (dc->flags & DC_GDB)
229 				boothowto |= RB_GDB;
230 #endif
231 			breakpoint();
232 		}
233 	}
234 	if (c == KEY_CR)
235 		dc->brk_state = STATE1;
236 #endif
237 	return (c);
238 }
239 #else
240 #define	dcons_check_break(dc, c)	(c)
241 #endif
242 
243 static int
244 dcons_os_checkc(struct dcons_softc *dc)
245 {
246 	int c;
247 
248 	EVENTHANDLER_INVOKE(dcons_poll, 0);
249 	if (dg.dma_tag != NULL)
250 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_POSTREAD);
251 
252 	c = dcons_check_break(dc, dcons_checkc(dc));
253 
254 	if (dg.dma_tag != NULL)
255 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_PREREAD);
256 
257 	return (c);
258 }
259 
260 #if defined(GDB) || !defined(CONS_NODEV)
261 static int
262 dcons_os_getc(struct dcons_softc *dc)
263 {
264 	int c;
265 
266 	while ((c = dcons_os_checkc(dc)) == -1);
267 
268 	return (c & 0xff);
269 }
270 #endif
271 
272 static void
273 dcons_os_putc(struct dcons_softc *dc, int c)
274 {
275 	if (dg.dma_tag != NULL)
276 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_POSTWRITE);
277 
278 	dcons_putc(dc, c);
279 
280 	if (dg.dma_tag != NULL)
281 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_PREWRITE);
282 }
283 static int
284 dcons_open(DEV dev, int flag, int mode, THREAD *td)
285 {
286 	struct tty *tp;
287 	int unit, error, s;
288 
289 	unit = minor(dev);
290 	if (unit != 0)
291 		return (ENXIO);
292 
293 	tp = dev->si_tty;
294 	tp->t_oproc = dcons_tty_start;
295 	tp->t_param = dcons_tty_param;
296 	tp->t_stop = nottystop;
297 	tp->t_dev = dev;
298 
299 	error = 0;
300 
301 	s = spltty();
302 	if ((tp->t_state & TS_ISOPEN) == 0) {
303 		tp->t_state |= TS_CARR_ON;
304 		ttyconsolemode(tp, 0);
305 	} else if ((tp->t_state & TS_XCLUDE) &&
306 	    priv_check(td, PRIV_TTY_EXCLUSIVE)) {
307 		splx(s);
308 		return (EBUSY);
309 	}
310 	splx(s);
311 
312 #if __FreeBSD_version < 502113
313 	error = (*linesw[tp->t_line].l_open)(dev, tp);
314 #else
315 	error = ttyld_open(tp, dev);
316 #endif
317 
318 	return (error);
319 }
320 
321 static int
322 dcons_close(DEV dev, int flag, int mode, THREAD *td)
323 {
324 	int	unit;
325 	struct	tty *tp;
326 
327 	unit = minor(dev);
328 	if (unit != 0)
329 		return (ENXIO);
330 
331 	tp = dev->si_tty;
332 	if (tp->t_state & TS_ISOPEN) {
333 #if __FreeBSD_version < 502113
334 		(*linesw[tp->t_line].l_close)(tp, flag);
335 		ttyclose(tp);
336 #else
337 		ttyld_close(tp, flag);
338 		tty_close(tp);
339 #endif
340 	}
341 
342 	return (0);
343 }
344 
345 #if defined(__DragonFly__) || __FreeBSD_version < 500104
346 static int
347 dcons_ioctl(DEV dev, u_long cmd, caddr_t data, int flag, THREAD *td)
348 {
349 	int	unit;
350 	struct	tty *tp;
351 	int	error;
352 
353 	unit = minor(dev);
354 	if (unit != 0)
355 		return (ENXIO);
356 
357 	tp = dev->si_tty;
358 	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, td);
359 	if (error != ENOIOCTL)
360 		return (error);
361 
362 	error = ttioctl(tp, cmd, data, flag);
363 	if (error != ENOIOCTL)
364 		return (error);
365 
366 	return (ENOTTY);
367 }
368 #endif
369 
370 static int
371 dcons_tty_param(struct tty *tp, struct termios *t)
372 {
373 	tp->t_ispeed = t->c_ispeed;
374 	tp->t_ospeed = t->c_ospeed;
375 	tp->t_cflag = t->c_cflag;
376 	return 0;
377 }
378 
379 static void
380 dcons_tty_start(struct tty *tp)
381 {
382 	struct dcons_softc *dc;
383 	int s;
384 
385 	dc = (struct dcons_softc *)tp->t_dev->si_drv1;
386 	s = spltty();
387 	if (tp->t_state & (TS_TIMEOUT | TS_TTSTOP)) {
388 		ttwwakeup(tp);
389 		return;
390 	}
391 
392 	tp->t_state |= TS_BUSY;
393 	while (tp->t_outq.c_cc != 0)
394 		dcons_os_putc(dc, getc(&tp->t_outq));
395 	tp->t_state &= ~TS_BUSY;
396 
397 	ttwwakeup(tp);
398 	splx(s);
399 }
400 
401 static void
402 dcons_timeout(void *v)
403 {
404 	struct	tty *tp;
405 	struct dcons_softc *dc;
406 	int i, c, polltime;
407 
408 	for (i = 0; i < DCONS_NPORT; i ++) {
409 		dc = &sc[i];
410 		tp = ((DEV)dc->dev)->si_tty;
411 		while ((c = dcons_os_checkc(dc)) != -1)
412 			if (tp->t_state & TS_ISOPEN)
413 #if __FreeBSD_version < 502113
414 				(*linesw[tp->t_line].l_rint)(c, tp);
415 #else
416 				ttyld_rint(tp, c);
417 #endif
418 	}
419 	polltime = hz / poll_hz;
420 	if (polltime < 1)
421 		polltime = 1;
422 	callout_reset(&dcons_callout, polltime, dcons_timeout, tp);
423 }
424 
425 static void
426 dcons_cnprobe(struct consdev *cp)
427 {
428 #ifdef __DragonFly__
429 	cp->cn_dev = make_dev(&dcons_cdevsw, DCONS_CON,
430 	    UID_ROOT, GID_WHEEL, 0600, "dcons");
431 #elif __FreeBSD_version >= 501109
432 	sprintf(cp->cn_name, "dcons");
433 #else
434 	cp->cn_dev = makedev(CDEV_MAJOR, DCONS_CON);
435 #endif
436 #if DCONS_FORCE_CONSOLE
437 	cp->cn_pri = CN_REMOTE;
438 #else
439 	cp->cn_pri = CN_NORMAL;
440 #endif
441 }
442 
443 static void
444 dcons_cninit(struct consdev *cp)
445 {
446 	dcons_drv_init(0);
447 #if CONS_NODEV
448 	cp->cn_arg
449 #else
450 	cp->cn_dev->si_drv1
451 #endif
452 		= (void *)&sc[DCONS_CON]; /* share port0 with unit0 */
453 }
454 
455 static void
456 dcons_cnterm(struct consdev *cp)
457 {
458 }
459 
460 #if CONS_NODEV
461 static int
462 dcons_cngetc(struct consdev *cp)
463 {
464 	struct dcons_softc *dc = (struct dcons_softc *)cp->cn_arg;
465 	return (dcons_os_checkc(dc));
466 }
467 static void
468 dcons_cnputc(struct consdev *cp, int c)
469 {
470 	struct dcons_softc *dc = (struct dcons_softc *)cp->cn_arg;
471 	dcons_os_putc(dc, c);
472 }
473 #else
474 static int
475 dcons_cngetc(DEV dev)
476 {
477 	struct dcons_softc *dc = (struct dcons_softc *)dev->si_drv1;
478 	return (dcons_os_getc(dc));
479 }
480 static int
481 dcons_cncheckc(DEV dev)
482 {
483 	struct dcons_softc *dc = (struct dcons_softc *)dev->si_drv1;
484 	return (dcons_os_checkc(dc));
485 }
486 static void
487 dcons_cnputc(DEV dev, int c)
488 {
489 	struct dcons_softc *dc = (struct dcons_softc *)dev->si_drv1;
490 	dcons_os_putc(dc, c);
491 }
492 #endif
493 
494 static int
495 dcons_drv_init(int stage)
496 {
497 #if defined(__i386__) || defined(__amd64__)
498 	quad_t addr, size;
499 #endif
500 
501 	if (drv_init)
502 		return(drv_init);
503 
504 	drv_init = -1;
505 
506 	bzero(&dg, sizeof(dg));
507 	dcons_conf = &dg;
508 	dg.cdev = &dcons_consdev;
509 	dg.buf = NULL;
510 	dg.size = DCONS_BUF_SIZE;
511 
512 #if defined(__i386__) || defined(__amd64__)
513 	if (getenv_quad("dcons.addr", &addr) > 0 &&
514 	    getenv_quad("dcons.size", &size) > 0) {
515 #ifdef __i386__
516 		vm_paddr_t pa;
517 		/*
518 		 * Allow read/write access to dcons buffer.
519 		 */
520 		for (pa = trunc_page(addr); pa < addr + size; pa += PAGE_SIZE)
521 			*vtopte(KERNBASE + pa) |= PG_RW;
522 		invltlb();
523 #endif
524 		/* XXX P to V */
525 		dg.buf = (struct dcons_buf *)(vm_offset_t)(KERNBASE + addr);
526 		dg.size = size;
527 		if (dcons_load_buffer(dg.buf, dg.size, sc) < 0)
528 			dg.buf = NULL;
529 	}
530 #endif
531 	if (dg.buf != NULL)
532 		goto ok;
533 
534 #ifndef KLD_MODULE
535 	if (stage == 0) { /* XXX or cold */
536 		/*
537 		 * DCONS_FORCE_CONSOLE == 1 and statically linked.
538 		 * called from cninit(). can't use contigmalloc yet .
539 		 */
540 		dg.buf = (struct dcons_buf *) bssbuf;
541 		dcons_init(dg.buf, dg.size, sc);
542 	} else
543 #endif
544 	{
545 		/*
546 		 * DCONS_FORCE_CONSOLE == 0 or kernel module case.
547 		 * if the module is loaded after boot,
548 		 * bssbuf could be non-continuous.
549 		 */
550 		dg.buf = (struct dcons_buf *) contigmalloc(dg.size,
551 			M_DEVBUF, 0, 0x10000, 0xffffffff, PAGE_SIZE, 0ul);
552 		dcons_init(dg.buf, dg.size, sc);
553 	}
554 
555 ok:
556 	dcons_buf = dg.buf;
557 
558 #if __FreeBSD_version < 502122
559 #if defined(DDB) && DCONS_FORCE_GDB
560 #if CONS_NODEV
561 	gdbconsdev.cn_arg = (void *)&sc[DCONS_GDB];
562 #if __FreeBSD_version >= 501109
563 	sprintf(gdbconsdev.cn_name, "dgdb");
564 #endif
565 	gdb_arg = &gdbconsdev;
566 #elif defined(__DragonFly__)
567 	gdbdev = make_dev(&dcons_cdevsw, DCONS_GDB,
568 	    UID_ROOT, GID_WHEEL, 0600, "dgdb");
569 #else
570 	gdbdev = makedev(CDEV_MAJOR, DCONS_GDB);
571 #endif
572 	gdb_getc = dcons_cngetc;
573 	gdb_putc = dcons_cnputc;
574 #endif
575 #endif
576 	drv_init = 1;
577 
578 	return 0;
579 }
580 
581 
582 static int
583 dcons_attach_port(int port, char *name, int flags)
584 {
585 	struct dcons_softc *dc;
586 	struct tty *tp;
587 	DEV dev;
588 
589 	dc = &sc[port];
590 	dc->flags = flags;
591 	dev = make_dev(&dcons_cdevsw, port,
592 			UID_ROOT, GID_WHEEL, 0600, name);
593 	dc->dev = (void *)dev;
594 	tp = ttyalloc();
595 
596 	dev->si_drv1 = (void *)dc;
597 	dev->si_tty = tp;
598 
599 	tp->t_oproc = dcons_tty_start;
600 	tp->t_param = dcons_tty_param;
601 	tp->t_stop = nottystop;
602 	tp->t_dev = dc->dev;
603 
604 	return(0);
605 }
606 
607 static int
608 dcons_attach(void)
609 {
610 	int polltime;
611 
612 #ifdef __DragonFly__
613 	cdevsw_add(&dcons_cdevsw, -1, 0);
614 #endif
615 	dcons_attach_port(DCONS_CON, "dcons", 0);
616 	dcons_attach_port(DCONS_GDB, "dgdb", DC_GDB);
617 #if __FreeBSD_version < 500000
618 	callout_init(&dcons_callout);
619 #else
620 	callout_init(&dcons_callout, 0);
621 #endif
622 	polltime = hz / poll_hz;
623 	if (polltime < 1)
624 		polltime = 1;
625 	callout_reset(&dcons_callout, polltime, dcons_timeout, NULL);
626 	return(0);
627 }
628 
629 static int
630 dcons_detach(int port)
631 {
632 	struct	tty *tp;
633 	struct dcons_softc *dc;
634 
635 	dc = &sc[port];
636 
637 	tp = ((DEV)dc->dev)->si_tty;
638 
639 	if (tp->t_state & TS_ISOPEN) {
640 		printf("dcons: still opened\n");
641 #if __FreeBSD_version < 502113
642 		(*linesw[tp->t_line].l_close)(tp, 0);
643 		tp->t_gen++;
644 		ttyclose(tp);
645 		ttwakeup(tp);
646 		ttwwakeup(tp);
647 #else
648 		ttyld_close(tp, 0);
649 		tty_close(tp);
650 #endif
651 	}
652 	/* XXX
653 	 * must wait until all device are closed.
654 	 */
655 #ifdef __DragonFly__
656 	tsleep((void *)dc, 0, "dcodtc", hz/4);
657 #else
658 	tsleep((void *)dc, PWAIT, "dcodtc", hz/4);
659 #endif
660 	destroy_dev(dc->dev);
661 
662 	return(0);
663 }
664 
665 
666 /* cnXXX works only for FreeBSD-5 */
667 static int
668 dcons_modevent(module_t mode, int type, void *data)
669 {
670 	int err = 0, ret;
671 
672 	switch (type) {
673 	case MOD_LOAD:
674 		ret = dcons_drv_init(1);
675 		dcons_attach();
676 #if __FreeBSD_version >= 500000
677 		if (ret == 0) {
678 			dcons_cnprobe(&dcons_consdev);
679 			dcons_cninit(&dcons_consdev);
680 			cnadd(&dcons_consdev);
681 		}
682 #endif
683 		break;
684 	case MOD_UNLOAD:
685 		printf("dcons: unload\n");
686 		callout_stop(&dcons_callout);
687 #if __FreeBSD_version < 502122
688 #if defined(DDB) && DCONS_FORCE_GDB
689 #if CONS_NODEV
690 		gdb_arg = NULL;
691 #else
692 		gdbdev = NULL;
693 #endif
694 #endif
695 #endif
696 #if __FreeBSD_version >= 500000
697 		cnremove(&dcons_consdev);
698 #endif
699 		dcons_detach(DCONS_CON);
700 		dcons_detach(DCONS_GDB);
701 		dg.buf->magic = 0;
702 
703 		contigfree(dg.buf, DCONS_BUF_SIZE, M_DEVBUF);
704 
705 		break;
706 	case MOD_SHUTDOWN:
707 #if 0		/* Keep connection after halt */
708 		dg.buf->magic = 0;
709 #endif
710 		break;
711 	default:
712 		err = EOPNOTSUPP;
713 		break;
714 	}
715 	return(err);
716 }
717 
718 #if defined(GDB) && (__FreeBSD_version >= 502122)
719 /* Debugger interface */
720 
721 static int
722 dcons_dbg_probe(void)
723 {
724 	int dcons_gdb;
725 
726 	if (getenv_int("dcons_gdb", &dcons_gdb) == 0)
727 		return (-1);
728 	return (dcons_gdb);
729 }
730 
731 static void
732 dcons_dbg_init(void)
733 {
734 }
735 
736 static void
737 dcons_dbg_term(void)
738 {
739 }
740 
741 static void
742 dcons_dbg_putc(int c)
743 {
744 	struct dcons_softc *dc = &sc[DCONS_GDB];
745 	dcons_os_putc(dc, c);
746 }
747 
748 static int
749 dcons_dbg_getc(void)
750 {
751 	struct dcons_softc *dc = &sc[DCONS_GDB];
752 	return (dcons_os_getc(dc));
753 }
754 #endif
755 
756 DEV_MODULE(dcons, dcons_modevent, NULL);
757 MODULE_VERSION(dcons, DCONS_VERSION);
758