xref: /freebsd/sys/dev/dcons/dcons_os.c (revision 7899f917b1c0ea178f1d2be0cfb452086d079d23)
1 /*-
2  * SPDX-License-Identifier: BSD-4-Clause
3  *
4  * Copyright (C) 2003,2004
5  * 	Hidetoshi Shimokawa. All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *
18  *	This product includes software developed by Hidetoshi Shimokawa.
19  *
20  * 4. Neither the name of the author nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #include <sys/param.h>
38 #include <sys/eventhandler.h>
39 #include <sys/kdb.h>
40 #include <gdb/gdb.h>
41 #include <sys/kernel.h>
42 #include <sys/module.h>
43 #include <sys/systm.h>
44 #include <sys/types.h>
45 #include <sys/conf.h>
46 #include <sys/cons.h>
47 #include <sys/consio.h>
48 #include <sys/tty.h>
49 #include <sys/malloc.h>
50 #include <sys/priv.h>
51 #include <sys/proc.h>
52 #include <sys/ucred.h>
53 
54 #include <machine/atomic.h>
55 #include <machine/bus.h>
56 
57 #include <dev/dcons/dcons.h>
58 #include <dev/dcons/dcons_os.h>
59 
60 #include <ddb/ddb.h>
61 #include <sys/reboot.h>
62 
63 #include <sys/sysctl.h>
64 
65 #include <vm/vm.h>
66 #include <vm/vm_param.h>
67 #include <vm/pmap.h>
68 
69 #include "opt_dcons.h"
70 #include "opt_kdb.h"
71 #include "opt_gdb.h"
72 #include "opt_ddb.h"
73 
74 
75 #ifndef DCONS_POLL_HZ
76 #define DCONS_POLL_HZ	25
77 #endif
78 
79 #ifndef DCONS_POLL_IDLE
80 #define DCONS_POLL_IDLE	256
81 #endif
82 
83 #ifndef DCONS_BUF_SIZE
84 #define DCONS_BUF_SIZE (16*1024)
85 #endif
86 
87 #ifndef DCONS_FORCE_CONSOLE
88 #define DCONS_FORCE_CONSOLE	0	/* Mostly for FreeBSD-4/DragonFly */
89 #endif
90 
91 #ifndef KLD_MODULE
92 static char bssbuf[DCONS_BUF_SIZE];	/* buf in bss */
93 #endif
94 
95 /* global data */
96 static struct dcons_global dg;
97 struct dcons_global *dcons_conf;
98 static int poll_hz = DCONS_POLL_HZ;
99 static u_int poll_idle = DCONS_POLL_HZ * DCONS_POLL_IDLE;
100 
101 static struct dcons_softc sc[DCONS_NPORT];
102 
103 static SYSCTL_NODE(_kern, OID_AUTO, dcons, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
104     "Dumb Console");
105 SYSCTL_INT(_kern_dcons, OID_AUTO, poll_hz, CTLFLAG_RW, &poll_hz, 0,
106 				"dcons polling rate");
107 
108 static int drv_init = 0;
109 static struct callout dcons_callout;
110 struct dcons_buf *dcons_buf;		/* for local dconschat */
111 
112 static void	dcons_timeout(void *);
113 static int	dcons_drv_init(int);
114 
115 static cn_probe_t	dcons_cnprobe;
116 static cn_init_t	dcons_cninit;
117 static cn_term_t	dcons_cnterm;
118 static cn_getc_t	dcons_cngetc;
119 static cn_putc_t	dcons_cnputc;
120 static cn_grab_t	dcons_cngrab;
121 static cn_ungrab_t	dcons_cnungrab;
122 
123 CONSOLE_DRIVER(dcons);
124 
125 #if defined(GDB)
126 static gdb_probe_f	dcons_dbg_probe;
127 static gdb_init_f	dcons_dbg_init;
128 static gdb_term_f	dcons_dbg_term;
129 static gdb_getc_f	dcons_dbg_getc;
130 static gdb_putc_f	dcons_dbg_putc;
131 
132 GDB_DBGPORT(dcons, dcons_dbg_probe, dcons_dbg_init, dcons_dbg_term,
133     dcons_dbg_getc, dcons_dbg_putc);
134 
135 extern struct gdb_dbgport *gdb_cur;
136 #endif
137 
138 static tsw_outwakeup_t dcons_outwakeup;
139 static tsw_free_t      dcons_free;
140 
141 static struct ttydevsw dcons_ttydevsw = {
142 	.tsw_flags      = TF_NOPREFIX,
143 	.tsw_outwakeup  = dcons_outwakeup,
144 	.tsw_free       = dcons_free,
145 };
146 
147 static int dcons_close_refs;
148 
149 #if (defined(GDB) || defined(DDB))
150 static int
151 dcons_check_break(struct dcons_softc *dc, int c)
152 {
153 
154 	if (c < 0)
155 		return (c);
156 
157 #ifdef GDB
158 	if ((dc->flags & DC_GDB) != 0 && gdb_cur == &dcons_gdb_dbgport)
159 		kdb_alt_break_gdb(c, &dc->brk_state);
160 	else
161 #endif
162 		kdb_alt_break(c, &dc->brk_state);
163 
164 	return (c);
165 }
166 #else
167 #define	dcons_check_break(dc, c)	(c)
168 #endif
169 
170 static int
171 dcons_os_checkc_nopoll(struct dcons_softc *dc)
172 {
173 	int c;
174 
175 	if (dg.dma_tag != NULL)
176 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_POSTREAD);
177 
178 	c = dcons_check_break(dc, dcons_checkc(dc));
179 
180 	if (dg.dma_tag != NULL)
181 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_PREREAD);
182 
183 	return (c);
184 }
185 
186 static int
187 dcons_os_checkc(struct dcons_softc *dc)
188 {
189 	EVENTHANDLER_INVOKE(dcons_poll, 0);
190 	return (dcons_os_checkc_nopoll(dc));
191 }
192 
193 static void
194 dcons_os_putc(struct dcons_softc *dc, int c)
195 {
196 	if (dg.dma_tag != NULL)
197 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_POSTWRITE);
198 
199 	dcons_putc(dc, c);
200 
201 	if (dg.dma_tag != NULL)
202 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_PREWRITE);
203 }
204 
205 static void
206 dcons_free(void *xsc __unused)
207 {
208 
209 	/* Our deferred free has arrived, now we're waiting for one fewer. */
210 	atomic_subtract_rel_int(&dcons_close_refs, 1);
211 }
212 
213 static void
214 dcons_outwakeup(struct tty *tp)
215 {
216 	struct dcons_softc *dc;
217 	char ch;
218 
219 	dc = tty_softc(tp);
220 
221 	while (ttydisc_getc(tp, &ch, sizeof ch) != 0)
222 		dcons_os_putc(dc, ch);
223 }
224 
225 static void
226 dcons_timeout(void *v)
227 {
228 	struct	tty *tp;
229 	struct dcons_softc *dc;
230 	int i, c, polltime;
231 
232 	for (i = 0; i < DCONS_NPORT; i ++) {
233 		dc = &sc[i];
234 		tp = dc->tty;
235 
236 		tty_lock(tp);
237 		while ((c = dcons_os_checkc_nopoll(dc)) != -1) {
238 			ttydisc_rint(tp, c, 0);
239 			poll_idle = 0;
240 		}
241 		ttydisc_rint_done(tp);
242 		tty_unlock(tp);
243 	}
244 	poll_idle++;
245 	polltime = hz;
246 	if (poll_idle <= (poll_hz * DCONS_POLL_IDLE))
247 		polltime /= poll_hz;
248 	callout_reset(&dcons_callout, polltime, dcons_timeout, tp);
249 }
250 
251 static void
252 dcons_cnprobe(struct consdev *cp)
253 {
254 	sprintf(cp->cn_name, "dcons");
255 #if DCONS_FORCE_CONSOLE
256 	cp->cn_pri = CN_REMOTE;
257 #else
258 	cp->cn_pri = CN_NORMAL;
259 #endif
260 }
261 
262 static void
263 dcons_cninit(struct consdev *cp)
264 {
265 	dcons_drv_init(0);
266 	cp->cn_arg = (void *)&sc[DCONS_CON]; /* share port0 with unit0 */
267 }
268 
269 static void
270 dcons_cnterm(struct consdev *cp)
271 {
272 }
273 
274 static void
275 dcons_cngrab(struct consdev *cp)
276 {
277 }
278 
279 static void
280 dcons_cnungrab(struct consdev *cp)
281 {
282 }
283 
284 static int
285 dcons_cngetc(struct consdev *cp)
286 {
287 	struct dcons_softc *dc = (struct dcons_softc *)cp->cn_arg;
288 	return (dcons_os_checkc(dc));
289 }
290 
291 static void
292 dcons_cnputc(struct consdev *cp, int c)
293 {
294 	struct dcons_softc *dc = (struct dcons_softc *)cp->cn_arg;
295 	dcons_os_putc(dc, c);
296 }
297 
298 static int
299 dcons_drv_init(int stage)
300 {
301 #if defined(__i386__) || defined(__amd64__)
302 	quad_t addr, size;
303 #endif
304 
305 	if (drv_init)
306 		return(drv_init);
307 
308 	drv_init = -1;
309 
310 	bzero(&dg, sizeof(dg));
311 	dcons_conf = &dg;
312 	dg.cdev = &dcons_consdev;
313 	dg.buf = NULL;
314 	dg.size = DCONS_BUF_SIZE;
315 
316 #if defined(__i386__) || defined(__amd64__)
317 	if (getenv_quad("dcons.addr", &addr) > 0 &&
318 	    getenv_quad("dcons.size", &size) > 0) {
319 #ifdef __i386__
320 		vm_paddr_t pa;
321 		/*
322 		 * Allow read/write access to dcons buffer.
323 		 */
324 		for (pa = trunc_page(addr); pa < addr + size; pa += PAGE_SIZE)
325 			pmap_ksetrw(PMAP_MAP_LOW + pa);
326 		invltlb();
327 #endif
328 		/* XXX P to V */
329 #ifdef __amd64__
330 		dg.buf = (struct dcons_buf *)(vm_offset_t)(KERNBASE + addr);
331 #else /* __i386__ */
332 		dg.buf = (struct dcons_buf *)(vm_offset_t)(PMAP_MAP_LOW +
333 		    addr);
334 #endif
335 		dg.size = size;
336 		if (dcons_load_buffer(dg.buf, dg.size, sc) < 0)
337 			dg.buf = NULL;
338 	}
339 #endif
340 	if (dg.buf != NULL)
341 		goto ok;
342 
343 #ifndef KLD_MODULE
344 	if (stage == 0) { /* XXX or cold */
345 		/*
346 		 * DCONS_FORCE_CONSOLE == 1 and statically linked.
347 		 * called from cninit(). can't use contigmalloc yet .
348 		 */
349 		dg.buf = (struct dcons_buf *) bssbuf;
350 		dcons_init(dg.buf, dg.size, sc);
351 	} else
352 #endif
353 	{
354 		/*
355 		 * DCONS_FORCE_CONSOLE == 0 or kernel module case.
356 		 * if the module is loaded after boot,
357 		 * bssbuf could be non-continuous.
358 		 */
359 		dg.buf = (struct dcons_buf *) contigmalloc(dg.size,
360 			M_DEVBUF, 0, 0x10000, 0xffffffff, PAGE_SIZE, 0ul);
361 		if (dg.buf == NULL)
362 			return (-1);
363 		dcons_init(dg.buf, dg.size, sc);
364 	}
365 
366 ok:
367 	dcons_buf = dg.buf;
368 
369 	drv_init = 1;
370 
371 	return 0;
372 }
373 
374 
375 static int
376 dcons_attach_port(int port, char *name, int flags)
377 {
378 	struct dcons_softc *dc;
379 	struct tty *tp;
380 
381 	dc = &sc[port];
382 	tp = tty_alloc(&dcons_ttydevsw, dc);
383 	dc->flags = flags;
384 	dc->tty   = tp;
385 	tty_init_console(tp, 0);
386 	tty_makedev(tp, NULL, "%s", name);
387 	return(0);
388 }
389 
390 static int
391 dcons_attach(void)
392 {
393 	int polltime;
394 
395 	dcons_attach_port(DCONS_CON, "dcons", 0);
396 	dcons_attach_port(DCONS_GDB, "dgdb", DC_GDB);
397 	callout_init(&dcons_callout, 1);
398 	polltime = hz / poll_hz;
399 	callout_reset(&dcons_callout, polltime, dcons_timeout, NULL);
400 	return(0);
401 }
402 
403 static int
404 dcons_detach(int port)
405 {
406 	struct	tty *tp;
407 	struct dcons_softc *dc;
408 
409 	dc = &sc[port];
410 	tp = dc->tty;
411 
412 	/* tty_rel_gone() schedules a deferred free callback, count it. */
413 	atomic_add_int(&dcons_close_refs, 1);
414 	tty_lock(tp);
415 	tty_rel_gone(tp);
416 
417 	return(0);
418 }
419 
420 static int
421 dcons_modevent(module_t mode, int type, void *data)
422 {
423 	int err = 0, ret;
424 
425 	switch (type) {
426 	case MOD_LOAD:
427 		ret = dcons_drv_init(1);
428 		if (ret != -1)
429 			dcons_attach();
430 		if (ret == 0) {
431 			dcons_cnprobe(&dcons_consdev);
432 			dcons_cninit(&dcons_consdev);
433 			cnadd(&dcons_consdev);
434 		}
435 		break;
436 	case MOD_UNLOAD:
437 		printf("dcons: unload\n");
438 		if (drv_init == 1) {
439 			callout_stop(&dcons_callout);
440 			cnremove(&dcons_consdev);
441 			dcons_detach(DCONS_CON);
442 			dcons_detach(DCONS_GDB);
443 			dg.buf->magic = 0;
444 
445 			free(dg.buf, M_DEVBUF);
446 		}
447 
448 		/* Wait for tty deferred free callbacks to complete. */
449 		while (atomic_load_acq_int(&dcons_close_refs) > 0)
450                         pause_sbt("dcunld", mstosbt(50), mstosbt(10), 0);
451 		break;
452 	case MOD_SHUTDOWN:
453 #if 0		/* Keep connection after halt */
454 		dg.buf->magic = 0;
455 #endif
456 		break;
457 	default:
458 		err = EOPNOTSUPP;
459 		break;
460 	}
461 	return(err);
462 }
463 
464 #if defined(GDB)
465 /* Debugger interface */
466 
467 static int
468 dcons_os_getc(struct dcons_softc *dc)
469 {
470 	int c;
471 
472 	while ((c = dcons_os_checkc(dc)) == -1);
473 
474 	return (c & 0xff);
475 }
476 
477 static int
478 dcons_dbg_probe(void)
479 {
480 	int dcons_gdb;
481 
482 	if (getenv_int("dcons_gdb", &dcons_gdb) == 0)
483 		return (-1);
484 	return (dcons_gdb);
485 }
486 
487 static void
488 dcons_dbg_init(void)
489 {
490 }
491 
492 static void
493 dcons_dbg_term(void)
494 {
495 }
496 
497 static void
498 dcons_dbg_putc(int c)
499 {
500 	struct dcons_softc *dc = &sc[DCONS_GDB];
501 	dcons_os_putc(dc, c);
502 }
503 
504 static int
505 dcons_dbg_getc(void)
506 {
507 	struct dcons_softc *dc = &sc[DCONS_GDB];
508 	return (dcons_os_getc(dc));
509 }
510 #endif
511 
512 DEV_MODULE(dcons, dcons_modevent, NULL);
513 MODULE_VERSION(dcons, DCONS_VERSION);
514