xref: /freebsd/sys/dev/dcons/dcons.c (revision bda4474a591fa1287709d059699e5a0505511c24)
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/module.h>
41 #include <sys/systm.h>
42 #include <sys/types.h>
43 #include <sys/conf.h>
44 #include <sys/cons.h>
45 #include <sys/consio.h>
46 #include <sys/tty.h>
47 #include <sys/malloc.h>
48 #include <sys/proc.h>
49 #include <sys/ucred.h>
50 
51 #include <machine/bus.h>
52 
53 #include <dev/dcons/dcons.h>
54 
55 #include <ddb/ddb.h>
56 #include <sys/reboot.h>
57 
58 #include <sys/sysctl.h>
59 
60 #include "opt_ddb.h"
61 #include "opt_comconsole.h"
62 #include "opt_dcons.h"
63 
64 #ifndef DCONS_POLL_HZ
65 #define DCONS_POLL_HZ	100
66 #endif
67 
68 #ifndef DCONS_BUF_SIZE
69 #define DCONS_BUF_SIZE (16*1024)
70 #endif
71 
72 #ifndef DCONS_FORCE_CONSOLE
73 #define DCONS_FORCE_CONSOLE	0	/* mostly for FreeBSD-4 */
74 #endif
75 
76 #ifndef DCONS_FORCE_GDB
77 #define DCONS_FORCE_GDB	1
78 #endif
79 
80 #if __FreeBSD_version >= 500101
81 #define CONS_NODEV	1	/* for latest current */
82 static struct consdev gdbconsdev;
83 #endif
84 
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_version =	D_VERSION,
93 	.d_open =	dcons_open,
94 	.d_close =	dcons_close,
95 	.d_ioctl =	dcons_ioctl,
96 	.d_name =	"dcons",
97 	.d_flags =	D_TTY | D_NEEDGIANT,
98 #else
99 	/* open */	dcons_open,
100 	/* close */	dcons_close,
101 	/* read */	ttyread,
102 	/* write */	ttywrite,
103 	/* ioctl */	dcons_ioctl,
104 	/* poll */	ttypoll,
105 	/* mmap */	nommap,
106 	/* strategy */	nostrategy,
107 	/* name */	"dcons",
108 	/* major */	CDEV_MAJOR,
109 	/* dump */	nodump,
110 	/* psize */	nopsize,
111 	/* flags */	0,
112 #endif
113 };
114 
115 #ifndef KLD_MODULE
116 static char bssbuf[DCONS_BUF_SIZE];	/* buf in bss */
117 #endif
118 
119 /* global data */
120 static struct dcons_global dg;
121 struct dcons_global *dcons_conf;
122 static int poll_hz = DCONS_POLL_HZ;
123 
124 SYSCTL_NODE(_kern, OID_AUTO, dcons, CTLFLAG_RD, 0, "Dumb Console");
125 SYSCTL_INT(_kern_dcons, OID_AUTO, poll_hz, CTLFLAG_RW, &poll_hz, 0,
126 				"dcons polling rate");
127 
128 static int drv_init = 0;
129 static struct callout dcons_callout;
130 struct dcons_buf *dcons_buf;		/* for local dconschat */
131 
132 /* per device data */
133 static struct dcons_softc {
134 	dev_t dev;
135 	struct dcons_ch	o, i;
136 	int brk_state;
137 #define DC_GDB	1
138 	int flags;
139 } sc[DCONS_NPORT];
140 static void	dcons_tty_start(struct tty *);
141 static int	dcons_tty_param(struct tty *, struct termios *);
142 static void	dcons_timeout(void *);
143 static int	dcons_drv_init(int);
144 static int	dcons_getc(struct dcons_softc *);
145 static int	dcons_checkc(struct dcons_softc *);
146 static void	dcons_putc(struct dcons_softc *, int);
147 
148 static cn_probe_t	dcons_cnprobe;
149 static cn_init_t	dcons_cninit;
150 static cn_getc_t	dcons_cngetc;
151 static cn_checkc_t 	dcons_cncheckc;
152 static cn_putc_t	dcons_cnputc;
153 
154 CONS_DRIVER(dcons, dcons_cnprobe, dcons_cninit, NULL, dcons_cngetc,
155     dcons_cncheckc, dcons_cnputc, NULL);
156 
157 #if __FreeBSD_version < 500000
158 #define THREAD	proc
159 #else
160 #define THREAD	thread
161 #endif
162 
163 static int
164 dcons_open(dev_t dev, int flag, int mode, struct THREAD *td)
165 {
166 	struct tty *tp;
167 	int unit, error, s;
168 
169 	unit = minor(dev);
170 	if (unit != 0)
171 		return (ENXIO);
172 
173 	tp = dev->si_tty = ttymalloc(dev->si_tty);
174 	tp->t_oproc = dcons_tty_start;
175 	tp->t_param = dcons_tty_param;
176 	tp->t_stop = nottystop;
177 	tp->t_dev = dev;
178 
179 	error = 0;
180 
181 	s = spltty();
182 	if ((tp->t_state & TS_ISOPEN) == 0) {
183 		tp->t_state |= TS_CARR_ON;
184 		ttychars(tp);
185 		tp->t_iflag = TTYDEF_IFLAG;
186 		tp->t_oflag = TTYDEF_OFLAG;
187 		tp->t_cflag = TTYDEF_CFLAG|CLOCAL;
188 		tp->t_lflag = TTYDEF_LFLAG;
189 		tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
190 		ttsetwater(tp);
191 	} else if ((tp->t_state & TS_XCLUDE) && suser(td)) {
192 		splx(s);
193 		return (EBUSY);
194 	}
195 	splx(s);
196 
197 	error = (*linesw[tp->t_line].l_open)(dev, tp);
198 
199 	return (error);
200 }
201 
202 static int
203 dcons_close(dev_t dev, int flag, int mode, struct THREAD *td)
204 {
205 	int	unit;
206 	struct	tty *tp;
207 
208 	unit = minor(dev);
209 	if (unit != 0)
210 		return (ENXIO);
211 
212 	tp = dev->si_tty;
213 	if (tp->t_state & TS_ISOPEN) {
214 		(*linesw[tp->t_line].l_close)(tp, flag);
215 		ttyclose(tp);
216 	}
217 
218 	return (0);
219 }
220 
221 static int
222 dcons_ioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct THREAD *td)
223 {
224 	int	unit;
225 	struct	tty *tp;
226 	int	error;
227 
228 	unit = minor(dev);
229 	if (unit != 0)
230 		return (ENXIO);
231 
232 	tp = dev->si_tty;
233 	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, td);
234 	if (error != ENOIOCTL)
235 		return (error);
236 
237 	error = ttioctl(tp, cmd, data, flag);
238 	if (error != ENOIOCTL)
239 		return (error);
240 
241 	return (ENOTTY);
242 }
243 
244 static int
245 dcons_tty_param(struct tty *tp, struct termios *t)
246 {
247 	tp->t_ispeed = t->c_ispeed;
248 	tp->t_ospeed = t->c_ospeed;
249 	tp->t_cflag = t->c_cflag;
250 	return 0;
251 }
252 
253 static void
254 dcons_tty_start(struct tty *tp)
255 {
256 	struct dcons_softc *dc;
257 	int s;
258 
259 	dc = (struct dcons_softc *)tp->t_dev->si_drv1;
260 	s = spltty();
261 	if (tp->t_state & (TS_TIMEOUT | TS_TTSTOP)) {
262 		ttwwakeup(tp);
263 		return;
264 	}
265 
266 	tp->t_state |= TS_BUSY;
267 	while (tp->t_outq.c_cc != 0)
268 		dcons_putc(dc, getc(&tp->t_outq));
269 	tp->t_state &= ~TS_BUSY;
270 
271 	ttwwakeup(tp);
272 	splx(s);
273 }
274 
275 static void
276 dcons_timeout(void *v)
277 {
278 	struct	tty *tp;
279 	struct dcons_softc *dc;
280 	int i, c, polltime;
281 
282 	for (i = 0; i < DCONS_NPORT; i ++) {
283 		dc = &sc[i];
284 		tp = dc->dev->si_tty;
285 		while ((c = dcons_checkc(dc)) != -1)
286 			if (tp->t_state & TS_ISOPEN)
287 				(*linesw[tp->t_line].l_rint)(c, tp);
288 	}
289 	polltime = hz / poll_hz;
290 	if (polltime < 1)
291 		polltime = 1;
292 	callout_reset(&dcons_callout, polltime, dcons_timeout, tp);
293 }
294 
295 static void
296 dcons_cnprobe(struct consdev *cp)
297 {
298 #if __FreeBSD_version >= 501109
299 	sprintf(cp->cn_name, "dcons");
300 #else
301 	cp->cn_dev = makedev(CDEV_MAJOR, DCONS_CON);
302 #endif
303 #if DCONS_FORCE_CONSOLE
304 	cp->cn_pri = CN_REMOTE;
305 #else
306 	cp->cn_pri = CN_NORMAL;
307 #endif
308 }
309 
310 static void
311 dcons_cninit(struct consdev *cp)
312 {
313 	dcons_drv_init(0);
314 #if CONS_NODEV
315 	cp->cn_arg
316 #else
317 	cp->cn_dev->si_drv1
318 #endif
319 		= (void *)&sc[DCONS_CON]; /* share port0 with unit0 */
320 }
321 
322 #if CONS_NODEV
323 static int
324 dcons_cngetc(struct consdev *cp)
325 {
326 	return(dcons_getc((struct dcons_softc *)cp->cn_arg));
327 }
328 static int
329 dcons_cncheckc(struct consdev *cp)
330 {
331 	return(dcons_checkc((struct dcons_softc *)cp->cn_arg));
332 }
333 static void
334 dcons_cnputc(struct consdev *cp, int c)
335 {
336 	dcons_putc((struct dcons_softc *)cp->cn_arg, c);
337 }
338 #else
339 static int
340 dcons_cngetc(dev_t dev)
341 {
342 	return(dcons_getc((struct dcons_softc *)dev->si_drv1));
343 }
344 static int
345 dcons_cncheckc(dev_t dev)
346 {
347 	return(dcons_checkc((struct dcons_softc *)dev->si_drv1));
348 }
349 static void
350 dcons_cnputc(dev_t dev, int c)
351 {
352 	dcons_putc((struct dcons_softc *)dev->si_drv1, c);
353 }
354 #endif
355 
356 static int
357 dcons_getc(struct dcons_softc *dc)
358 {
359 	int c;
360 
361 	while ((c = dcons_checkc(dc)) == -1);
362 
363 	return (c & 0xff);
364 }
365 
366 static int
367 dcons_checkc(struct dcons_softc *dc)
368 {
369 	unsigned char c;
370 	u_int32_t ptr, pos, gen, next_gen;
371 	struct dcons_ch *ch;
372 
373 	ch = &dc->i;
374 
375 	if (dg.dma_tag != NULL)
376 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_POSTREAD);
377 	ptr = ntohl(*ch->ptr);
378 	gen = ptr >> DCONS_GEN_SHIFT;
379 	pos = ptr & DCONS_POS_MASK;
380 	if (gen == ch->gen && pos == ch->pos)
381 		return (-1);
382 
383 	next_gen = DCONS_NEXT_GEN(ch->gen);
384 	/* XXX sanity check */
385 	if ((gen != ch->gen && gen != next_gen)
386 			|| (gen == ch->gen && pos < ch->pos)) {
387 		/* generation skipped !! */
388 		/* XXX discard */
389 		ch->gen = gen;
390 		ch->pos = pos;
391 		return (-1);
392 	}
393 
394 	c = ch->buf[ch->pos];
395 	ch->pos ++;
396 	if (ch->pos >= ch->size) {
397 		ch->gen = next_gen;
398 		ch->pos = 0;
399 	}
400 
401 #if DDB && ALT_BREAK_TO_DEBUGGER
402 	switch (dc->brk_state) {
403 	case STATE1:
404 		if (c == KEY_TILDE)
405 			dc->brk_state = STATE2;
406 		else
407 			dc->brk_state = STATE0;
408 		break;
409 	case STATE2:
410 		dc->brk_state = STATE0;
411 		if (c == KEY_CTRLB) {
412 #if DCONS_FORCE_GDB
413 			if (dc->flags & DC_GDB)
414 				boothowto |= RB_GDB;
415 #endif
416 			breakpoint();
417 		}
418 	}
419 	if (c == KEY_CR)
420 		dc->brk_state = STATE1;
421 #endif
422 	return (c);
423 }
424 
425 static void
426 dcons_putc(struct dcons_softc *dc, int c)
427 {
428 	struct dcons_ch *ch;
429 
430 	ch = &dc->o;
431 
432 	ch->buf[ch->pos] = c;
433 	ch->pos ++;
434 	if (ch->pos >= ch->size) {
435 		ch->gen = DCONS_NEXT_GEN(ch->gen);
436 		ch->pos = 0;
437 	}
438 	*ch->ptr = DCONS_MAKE_PTR(ch);
439 	if (dg.dma_tag != NULL)
440 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_PREWRITE);
441 }
442 
443 static int
444 dcons_init_port(int port, int offset, int size)
445 {
446 	int osize;
447 	struct dcons_softc *dc;
448 
449 	dc = &sc[port];
450 
451 	osize = size * 3 / 4;
452 
453 	dc->o.size = osize;
454 	dc->i.size = size - osize;
455 	dc->o.buf = (char *)dg.buf + offset;
456 	dc->i.buf = dc->o.buf + osize;
457 	dc->o.gen = dc->i.gen = 0;
458 	dc->o.pos = dc->i.pos = 0;
459 	dc->o.ptr = &dg.buf->optr[port];
460 	dc->i.ptr = &dg.buf->iptr[port];
461 	dc->brk_state = STATE0;
462 	dg.buf->osize[port] = htonl(osize);
463 	dg.buf->isize[port] = htonl(size - osize);
464 	dg.buf->ooffset[port] = htonl(offset);
465 	dg.buf->ioffset[port] = htonl(offset + osize);
466 	dg.buf->optr[port] = DCONS_MAKE_PTR(&dc->o);
467 	dg.buf->iptr[port] = DCONS_MAKE_PTR(&dc->i);
468 
469 	return(0);
470 }
471 
472 static int
473 dcons_drv_init(int stage)
474 {
475 	int size, size0, offset;
476 
477 	if (drv_init)
478 		return(drv_init);
479 
480 	drv_init = -1;
481 
482 	bzero(&dg, sizeof(dg));
483 	dcons_conf = &dg;
484 	dg.cdev = &dcons_consdev;
485 	dg.size = 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 		dg.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 		 * bssbuf could be non-continuous.
500 		 */
501 		dg.buf = (struct dcons_buf *) contigmalloc(dg.size,
502 			M_DEVBUF, 0, 0x10000, 0xffffffff, PAGE_SIZE, 0ul);
503 
504 	dcons_buf = dg.buf;
505 	offset = DCONS_HEADER_SIZE;
506 	size = (dg.size - offset);
507 	size0 = size * 3 / 4;
508 
509 	dcons_init_port(0, offset, size0);
510 	offset += size0;
511 	dcons_init_port(1, offset, size - size0);
512 	dg.buf->version = htonl(DCONS_VERSION);
513 	dg.buf->magic = ntohl(DCONS_MAGIC);
514 
515 #if DDB && DCONS_FORCE_GDB
516 #if CONS_NODEV
517 	gdbconsdev.cn_arg = (void *)&sc[DCONS_GDB];
518 #if __FreeBSD_version >= 501109
519 	sprintf(gdbconsdev.cn_name, "dgdb");
520 #endif
521 	gdb_arg = &gdbconsdev;
522 #else
523 	gdbdev = makedev(CDEV_MAJOR, DCONS_GDB);
524 #endif
525 	gdb_getc = dcons_cngetc;
526 	gdb_putc = dcons_cnputc;
527 #endif
528 	drv_init = 1;
529 
530 	return 0;
531 }
532 
533 
534 static int
535 dcons_attach_port(int port, char *name, int flags)
536 {
537 	struct dcons_softc *dc;
538 	struct tty *tp;
539 
540 	dc = &sc[port];
541 	dc->flags = flags;
542 	dc->dev = make_dev(&dcons_cdevsw, port,
543 			UID_ROOT, GID_WHEEL, 0600, name);
544 	tp = ttymalloc(NULL);
545 
546 	dc->dev->si_drv1 = (void *)dc;
547 	dc->dev->si_tty = tp;
548 
549 	tp->t_oproc = dcons_tty_start;
550 	tp->t_param = dcons_tty_param;
551 	tp->t_stop = nottystop;
552 	tp->t_dev = dc->dev;
553 
554 	return(0);
555 }
556 
557 static int
558 dcons_attach(void)
559 {
560 	int polltime;
561 
562 	dcons_attach_port(DCONS_CON, "dcons", 0);
563 	dcons_attach_port(DCONS_GDB, "dgdb", DC_GDB);
564 #if __FreeBSD_version < 500000
565 	callout_init(&dcons_callout);
566 #else
567 	callout_init(&dcons_callout, 0);
568 #endif
569 	polltime = hz / poll_hz;
570 	if (polltime < 1)
571 		polltime = 1;
572 	callout_reset(&dcons_callout, polltime, dcons_timeout, NULL);
573 	return(0);
574 }
575 
576 static int
577 dcons_detach(int port)
578 {
579 	struct	tty *tp;
580 	struct dcons_softc *dc;
581 
582 	dc = &sc[port];
583 
584 	tp = dc->dev->si_tty;
585 
586 	if (tp->t_state & TS_ISOPEN) {
587 		printf("dcons: still opened\n");
588 		(*linesw[tp->t_line].l_close)(tp, 0);
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 		dg.buf->magic = 0;
637 
638 		contigfree(dg.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