xref: /freebsd/sys/dev/dcons/dcons.c (revision 52ec752989b2e6d4e9a59a8ff25d8ff596d85e62)
1 /*
2  * Copyright (C) 2003
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  * $Id: dcons.c,v 1.65 2003/10/24 03:24:55 simokawa Exp $
35  * $FreeBSD$
36  */
37 
38 #include <sys/param.h>
39 #include <sys/kernel.h>
40 #include <sys/systm.h>
41 #include <sys/types.h>
42 #include <sys/conf.h>
43 #include <sys/cons.h>
44 #include <sys/consio.h>
45 #include <sys/tty.h>
46 #include <sys/malloc.h>
47 #include <sys/proc.h>
48 #include <sys/ucred.h>
49 
50 #include <machine/bus.h>
51 
52 #include <dev/dcons/dcons.h>
53 
54 #include <ddb/ddb.h>
55 #include <sys/reboot.h>
56 
57 #include <sys/sysctl.h>
58 
59 #include "opt_ddb.h"
60 #include "opt_comconsole.h"
61 #include "opt_dcons.h"
62 
63 #ifndef DCONS_POLL_HZ
64 #define DCONS_POLL_HZ	100
65 #endif
66 
67 #ifndef DCONS_BUF_SIZE
68 #define DCONS_BUF_SIZE (16*1024)
69 #endif
70 
71 #ifndef DCONS_FORCE_CONSOLE
72 #define DCONS_FORCE_CONSOLE	0	/* mostly for FreeBSD-4 */
73 #endif
74 
75 #ifndef DCONS_FORCE_GDB
76 #define DCONS_FORCE_GDB	1
77 #endif
78 
79 #if __FreeBSD_version >= 500101
80 #define CONS_NODEV	1	/* for latest current */
81 static struct consdev gdbconsdev;
82 #endif
83 
84 #define	CDEV_MAJOR	184
85 
86 static d_open_t		dcons_open;
87 static d_close_t	dcons_close;
88 static d_ioctl_t	dcons_ioctl;
89 
90 static struct cdevsw dcons_cdevsw = {
91 #if __FreeBSD_version >= 500104
92 	.d_open =	dcons_open,
93 	.d_close =	dcons_close,
94 	.d_read =	ttyread,
95 	.d_write =	ttywrite,
96 	.d_ioctl =	dcons_ioctl,
97 	.d_poll =	ttypoll,
98 	.d_name =	"dcons",
99 	.d_maj =	CDEV_MAJOR,
100 #else
101 	/* open */	dcons_open,
102 	/* close */	dcons_close,
103 	/* read */	ttyread,
104 	/* write */	ttywrite,
105 	/* ioctl */	dcons_ioctl,
106 	/* poll */	ttypoll,
107 	/* mmap */	nommap,
108 	/* strategy */	nostrategy,
109 	/* name */	"dcons",
110 	/* major */	CDEV_MAJOR,
111 	/* dump */	nodump,
112 	/* psize */	nopsize,
113 	/* flags */	0,
114 #endif
115 };
116 
117 #ifndef KLD_MODULE
118 static char bssbuf[DCONS_BUF_SIZE];	/* buf in bss */
119 #endif
120 struct dcons_buf *dcons_buf;
121 size_t dcons_bufsize;
122 bus_dma_tag_t dcons_dma_tag = NULL;
123 bus_dmamap_t dcons_dma_map = NULL;
124 
125 static int poll_hz = DCONS_POLL_HZ;
126 SYSCTL_NODE(_kern, OID_AUTO, dcons, CTLFLAG_RD, 0, "Dumb Console");
127 SYSCTL_INT(_kern_dcons, OID_AUTO, poll_hz, CTLFLAG_RW, &poll_hz, 0,
128 				"dcons polling rate");
129 
130 static int drv_init = 0;
131 static struct callout dcons_callout;
132 
133 /* per device data */
134 static struct dcons_softc {
135 	dev_t dev;
136 	struct dcons_ch	o, i;
137 	int brk_state;
138 #define DC_GDB	1
139 	int flags;
140 } sc[DCONS_NPORT];
141 static void	dcons_tty_start(struct tty *);
142 static int	dcons_tty_param(struct tty *, struct termios *);
143 static void	dcons_timeout(void *);
144 static int	dcons_drv_init(int);
145 static int	dcons_getc(struct dcons_softc *);
146 static int	dcons_checkc(struct dcons_softc *);
147 static void	dcons_putc(struct dcons_softc *, int);
148 
149 static cn_probe_t	dcons_cnprobe;
150 static cn_init_t	dcons_cninit;
151 static cn_getc_t	dcons_cngetc;
152 static cn_checkc_t 	dcons_cncheckc;
153 static cn_putc_t	dcons_cnputc;
154 
155 CONS_DRIVER(dcons, dcons_cnprobe, dcons_cninit, NULL, dcons_cngetc,
156     dcons_cncheckc, dcons_cnputc, NULL);
157 
158 #if __FreeBSD_version < 500000
159 #define THREAD	proc
160 #else
161 #define THREAD	thread
162 #endif
163 
164 static int
165 dcons_open(dev_t dev, int flag, int mode, struct THREAD *td)
166 {
167 	struct tty *tp;
168 	int unit, error, s;
169 
170 	unit = minor(dev);
171 	if (unit != 0)
172 		return (ENXIO);
173 
174 	tp = dev->si_tty = ttymalloc(dev->si_tty);
175 	tp->t_oproc = dcons_tty_start;
176 	tp->t_param = dcons_tty_param;
177 	tp->t_stop = nottystop;
178 	tp->t_dev = dev;
179 
180 	error = 0;
181 
182 	s = spltty();
183 	if ((tp->t_state & TS_ISOPEN) == 0) {
184 		tp->t_state |= TS_CARR_ON;
185 		ttychars(tp);
186 		tp->t_iflag = TTYDEF_IFLAG;
187 		tp->t_oflag = TTYDEF_OFLAG;
188 		tp->t_cflag = TTYDEF_CFLAG|CLOCAL;
189 		tp->t_lflag = TTYDEF_LFLAG;
190 		tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
191 		ttsetwater(tp);
192 	} else if ((tp->t_state & TS_XCLUDE) && suser(td)) {
193 		splx(s);
194 		return (EBUSY);
195 	}
196 	splx(s);
197 
198 	error = (*linesw[tp->t_line].l_open)(dev, tp);
199 
200 	return (error);
201 }
202 
203 static int
204 dcons_close(dev_t dev, int flag, int mode, struct THREAD *td)
205 {
206 	int	unit;
207 	struct	tty *tp;
208 
209 	unit = minor(dev);
210 	if (unit != 0)
211 		return (ENXIO);
212 
213 	tp = dev->si_tty;
214 	if (tp->t_state & TS_ISOPEN) {
215 		(*linesw[tp->t_line].l_close)(tp, flag);
216 		ttyclose(tp);
217 	}
218 
219 	return (0);
220 }
221 
222 static int
223 dcons_ioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct THREAD *td)
224 {
225 	int	unit;
226 	struct	tty *tp;
227 	int	error;
228 
229 	unit = minor(dev);
230 	if (unit != 0)
231 		return (ENXIO);
232 
233 	tp = dev->si_tty;
234 	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, td);
235 	if (error != ENOIOCTL)
236 		return (error);
237 
238 	error = ttioctl(tp, cmd, data, flag);
239 	if (error != ENOIOCTL)
240 		return (error);
241 
242 	return (ENOTTY);
243 }
244 
245 static int
246 dcons_tty_param(struct tty *tp, struct termios *t)
247 {
248 	tp->t_ispeed = t->c_ispeed;
249 	tp->t_ospeed = t->c_ospeed;
250 	tp->t_cflag = t->c_cflag;
251 	return 0;
252 }
253 
254 static void
255 dcons_tty_start(struct tty *tp)
256 {
257 	struct dcons_softc *dc;
258 	int s;
259 
260 	dc = (struct dcons_softc *)tp->t_dev->si_drv1;
261 	s = spltty();
262 	if (tp->t_state & (TS_TIMEOUT | TS_TTSTOP)) {
263 		ttwwakeup(tp);
264 		return;
265 	}
266 
267 	tp->t_state |= TS_BUSY;
268 	while (tp->t_outq.c_cc != 0)
269 		dcons_putc(dc, getc(&tp->t_outq));
270 	tp->t_state &= ~TS_BUSY;
271 
272 	ttwwakeup(tp);
273 	splx(s);
274 }
275 
276 static void
277 dcons_timeout(void *v)
278 {
279 	struct	tty *tp;
280 	struct dcons_softc *dc;
281 	int i, c, polltime;
282 
283 	for (i = 0; i < DCONS_NPORT; i ++) {
284 		dc = &sc[i];
285 		tp = dc->dev->si_tty;
286 		while ((c = dcons_checkc(dc)) != -1)
287 			if (tp->t_state & TS_ISOPEN)
288 				(*linesw[tp->t_line].l_rint)(c, tp);
289 	}
290 	polltime = hz / poll_hz;
291 	if (polltime < 1)
292 		polltime = 1;
293 	callout_reset(&dcons_callout, polltime, dcons_timeout, tp);
294 }
295 
296 static void
297 dcons_cnprobe(struct consdev *cp)
298 {
299 #if __FreeBSD_version >= 501109
300 	sprintf(cp->cn_name, "dcons");
301 #else
302 	cp->cn_dev = makedev(CDEV_MAJOR, DCONS_CON);
303 #endif
304 #if DCONS_FORCE_CONSOLE
305 	cp->cn_pri = CN_REMOTE;
306 #else
307 	cp->cn_pri = CN_NORMAL;
308 #endif
309 }
310 
311 static void
312 dcons_cninit(struct consdev *cp)
313 {
314 	dcons_drv_init(0);
315 #if CONS_NODEV
316 	cp->cn_arg
317 #else
318 	cp->cn_dev->si_drv1
319 #endif
320 		= (void *)&sc[DCONS_CON]; /* share port0 with unit0 */
321 }
322 
323 #if CONS_NODEV
324 static int
325 dcons_cngetc(struct consdev *cp)
326 {
327 	return(dcons_getc((struct dcons_softc *)cp->cn_arg));
328 }
329 static int
330 dcons_cncheckc(struct consdev *cp)
331 {
332 	return(dcons_checkc((struct dcons_softc *)cp->cn_arg));
333 }
334 static void
335 dcons_cnputc(struct consdev *cp, int c)
336 {
337 	dcons_putc((struct dcons_softc *)cp->cn_arg, c);
338 }
339 #else
340 static int
341 dcons_cngetc(dev_t dev)
342 {
343 	return(dcons_getc((struct dcons_softc *)dev->si_drv1));
344 }
345 static int
346 dcons_cncheckc(dev_t dev)
347 {
348 	return(dcons_checkc((struct dcons_softc *)dev->si_drv1));
349 }
350 static void
351 dcons_cnputc(dev_t dev, int c)
352 {
353 	dcons_putc((struct dcons_softc *)dev->si_drv1, c);
354 }
355 #endif
356 
357 static int
358 dcons_getc(struct dcons_softc *dc)
359 {
360 	int c;
361 
362 	while ((c = dcons_checkc(dc)) == -1);
363 
364 	return (c & 0xff);
365 }
366 
367 static int
368 dcons_checkc(struct dcons_softc *dc)
369 {
370 	unsigned char c;
371 	u_int32_t ptr, pos, gen, next_gen;
372 	struct dcons_ch *ch;
373 
374 	ch = &dc->i;
375 
376 	if (dcons_dma_tag != NULL)
377 		bus_dmamap_sync(dcons_dma_tag, dcons_dma_map,
378 						BUS_DMASYNC_POSTREAD);
379 	ptr = ntohl(*ch->ptr);
380 	gen = ptr >> DCONS_GEN_SHIFT;
381 	pos = ptr & DCONS_POS_MASK;
382 	if (gen == ch->gen && pos == ch->pos)
383 		return (-1);
384 
385 	next_gen = DCONS_NEXT_GEN(ch->gen);
386 	/* XXX sanity check */
387 	if ((gen != ch->gen && gen != next_gen)
388 			|| (gen == ch->gen && pos < ch->pos)) {
389 		/* generation skipped !! */
390 		/* XXX discard */
391 		ch->gen = gen;
392 		ch->pos = pos;
393 		return (-1);
394 	}
395 
396 	c = ch->buf[ch->pos];
397 	ch->pos ++;
398 	if (ch->pos >= ch->size) {
399 		ch->gen = next_gen;
400 		ch->pos = 0;
401 	}
402 
403 #if DDB && ALT_BREAK_TO_DEBUGGER
404 	switch (dc->brk_state) {
405 	case STATE1:
406 		if (c == KEY_TILDE)
407 			dc->brk_state = STATE2;
408 		else
409 			dc->brk_state = STATE0;
410 		break;
411 	case STATE2:
412 		dc->brk_state = STATE0;
413 		if (c == KEY_CTRLB) {
414 #if DCONS_FORCE_GDB
415 			if (dc->flags & DC_GDB)
416 				boothowto |= RB_GDB;
417 #endif
418 			breakpoint();
419 		}
420 	}
421 	if (c == KEY_CR)
422 		dc->brk_state = STATE1;
423 #endif
424 	return (c);
425 }
426 
427 static void
428 dcons_putc(struct dcons_softc *dc, int c)
429 {
430 	struct dcons_ch *ch;
431 
432 	ch = &dc->o;
433 
434 	ch->buf[ch->pos] = c;
435 	ch->pos ++;
436 	if (ch->pos >= ch->size) {
437 		ch->gen = DCONS_NEXT_GEN(ch->gen);
438 		ch->pos = 0;
439 	}
440 	*ch->ptr = DCONS_MAKE_PTR(ch);
441 	if (dcons_dma_tag != NULL)
442 		bus_dmamap_sync(dcons_dma_tag, dcons_dma_map,
443 						BUS_DMASYNC_PREWRITE);
444 }
445 
446 static int
447 dcons_init_port(int port, int offset, int size)
448 {
449 	int osize;
450 	struct dcons_softc *dc;
451 
452 	dc = &sc[port];
453 
454 	osize = size * 3 / 4;
455 
456 	dc->o.size = osize;
457 	dc->i.size = size - osize;
458 	dc->o.buf = (char *)dcons_buf + offset;
459 	dc->i.buf = dc->o.buf + osize;
460 	dc->o.gen = dc->i.gen = 0;
461 	dc->o.pos = dc->i.pos = 0;
462 	dc->o.ptr = &dcons_buf->optr[port];
463 	dc->i.ptr = &dcons_buf->iptr[port];
464 	dc->brk_state = STATE0;
465 	dcons_buf->osize[port] = htonl(osize);
466 	dcons_buf->isize[port] = htonl(size - osize);
467 	dcons_buf->ooffset[port] = htonl(offset);
468 	dcons_buf->ioffset[port] = htonl(offset + osize);
469 	dcons_buf->optr[port] = DCONS_MAKE_PTR(&dc->o);
470 	dcons_buf->iptr[port] = DCONS_MAKE_PTR(&dc->i);
471 
472 	return(0);
473 }
474 
475 static int
476 dcons_drv_init(int stage)
477 {
478 	int size, size0, offset;
479 
480 	if (drv_init)
481 		return(drv_init);
482 
483 	drv_init = -1;
484 
485 	dcons_bufsize = DCONS_BUF_SIZE;
486 
487 #ifndef KLD_MODULE
488 	if (stage == 0) /* XXX or cold */
489 		/*
490 		 * DCONS_FORCE_CONSOLE == 1 and statically linked.
491 		 * called from cninit(). can't use contigmalloc yet .
492 		 */
493 		dcons_buf = (struct dcons_buf *) bssbuf;
494 	else
495 #endif
496 		/*
497 		 * DCONS_FORCE_CONSOLE == 0 or kernel module case.
498 		 * if the module is loaded after boot,
499 		 * dcons_buf could be non-continuous.
500 		 */
501 		dcons_buf = (struct dcons_buf *) contigmalloc(dcons_bufsize,
502 			M_DEVBUF, 0, 0x10000, 0xffffffff, PAGE_SIZE, 0ul);
503 
504 	offset = DCONS_HEADER_SIZE;
505 	size = (dcons_bufsize - offset);
506 	size0 = size * 3 / 4;
507 
508 	dcons_init_port(0, offset, size0);
509 	offset += size0;
510 	dcons_init_port(1, offset, size - size0);
511 	dcons_buf->version = htonl(DCONS_VERSION);
512 	dcons_buf->magic = ntohl(DCONS_MAGIC);
513 
514 #if DDB && DCONS_FORCE_GDB
515 #if CONS_NODEV
516 	gdbconsdev.cn_arg = (void *)&sc[DCONS_GDB];
517 #if __FreeBSD_version >= 501109
518 	sprintf(gdbconsdev.cn_name, "dgdb");
519 #endif
520 	gdb_arg = &gdbconsdev;
521 #else
522 	gdbdev = makedev(CDEV_MAJOR, DCONS_GDB);
523 #endif
524 	gdb_getc = dcons_cngetc;
525 	gdb_putc = dcons_cnputc;
526 #endif
527 	drv_init = 1;
528 
529 	return 0;
530 }
531 
532 
533 static int
534 dcons_attach_port(int port, char *name, int flags)
535 {
536 	struct dcons_softc *dc;
537 	struct tty *tp;
538 
539 	dc = &sc[port];
540 	dc->flags = flags;
541 	dc->dev = make_dev(&dcons_cdevsw, port,
542 			UID_ROOT, GID_WHEEL, 0600, name);
543 	tp = ttymalloc(NULL);
544 
545 	dc->dev->si_drv1 = (void *)dc;
546 	dc->dev->si_tty = tp;
547 
548 	tp->t_oproc = dcons_tty_start;
549 	tp->t_param = dcons_tty_param;
550 	tp->t_stop = nottystop;
551 	tp->t_dev = dc->dev;
552 
553 	return(0);
554 }
555 
556 static int
557 dcons_attach(void)
558 {
559 	int polltime;
560 
561 	dcons_attach_port(DCONS_CON, "dcons", 0);
562 	dcons_attach_port(DCONS_GDB, "dgdb", DC_GDB);
563 #if __FreeBSD_version < 500000
564 	callout_init(&dcons_callout);
565 #else
566 	callout_init(&dcons_callout, 0);
567 #endif
568 	polltime = hz / poll_hz;
569 	if (polltime < 1)
570 		polltime = 1;
571 	callout_reset(&dcons_callout, polltime, dcons_timeout, NULL);
572 	return(0);
573 }
574 
575 static int
576 dcons_detach(int port)
577 {
578 	struct	tty *tp;
579 	struct dcons_softc *dc;
580 
581 	dc = &sc[port];
582 
583 	tp = dc->dev->si_tty;
584 
585 	if (tp->t_state & TS_ISOPEN) {
586 		printf("dcons: still opened\n");
587 		(*linesw[tp->t_line].l_close)(tp, 0);
588 		tp->t_gen++;
589 		ttyclose(tp);
590 		ttwakeup(tp);
591 		ttwwakeup(tp);
592 	}
593 	/* XXX
594 	 * must wait until all device are closed.
595 	 */
596 	tsleep((void *)dc, PWAIT, "dcodtc", hz/4);
597 	destroy_dev(dc->dev);
598 
599 	return(0);
600 }
601 
602 
603 /* cnXXX works only for FreeBSD-5 */
604 static int
605 dcons_modevent(module_t mode, int type, void *data)
606 {
607 	int err = 0, ret;
608 
609 	switch (type) {
610 	case MOD_LOAD:
611 		ret = dcons_drv_init(1);
612 		dcons_attach();
613 #if __FreeBSD_version >= 500000
614 		if (ret == 0) {
615 			dcons_cnprobe(&dcons_consdev);
616 			dcons_cninit(&dcons_consdev);
617 			cnadd(&dcons_consdev);
618 		}
619 #endif
620 		break;
621 	case MOD_UNLOAD:
622 		printf("dcons: unload\n");
623 		callout_stop(&dcons_callout);
624 #if DDB && DCONS_FORCE_GDB
625 #if CONS_NODEV
626 		gdb_arg = NULL;
627 #else
628 		gdbdev = NODEV;
629 #endif
630 #endif
631 #if __FreeBSD_version >= 500000
632 		cnremove(&dcons_consdev);
633 #endif
634 		dcons_detach(DCONS_CON);
635 		dcons_detach(DCONS_GDB);
636 		dcons_buf->magic = 0;
637 
638 		contigfree(dcons_buf, DCONS_BUF_SIZE, M_DEVBUF);
639 
640 		break;
641 	case MOD_SHUTDOWN:
642 		break;
643 	}
644 	return(err);
645 }
646 
647 DEV_MODULE(dcons, dcons_modevent, NULL);
648 MODULE_VERSION(dcons, DCONS_VERSION);
649