xref: /freebsd/sys/dev/dcons/dcons_os.c (revision a0409676120c1e558d0ade943019934e0f15118d)
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  * $FreeBSD$
37  */
38 
39 #include <sys/param.h>
40 #include <sys/eventhandler.h>
41 #include <sys/kdb.h>
42 #include <gdb/gdb.h>
43 #include <sys/kernel.h>
44 #include <sys/module.h>
45 #include <sys/systm.h>
46 #include <sys/types.h>
47 #include <sys/conf.h>
48 #include <sys/cons.h>
49 #include <sys/consio.h>
50 #include <sys/tty.h>
51 #include <sys/malloc.h>
52 #include <sys/priv.h>
53 #include <sys/proc.h>
54 #include <sys/ucred.h>
55 
56 #include <machine/atomic.h>
57 #include <machine/bus.h>
58 
59 #include <dev/dcons/dcons.h>
60 #include <dev/dcons/dcons_os.h>
61 
62 #include <ddb/ddb.h>
63 #include <sys/reboot.h>
64 
65 #include <sys/sysctl.h>
66 
67 #include <vm/vm.h>
68 #include <vm/vm_param.h>
69 #include <vm/pmap.h>
70 
71 #include "opt_dcons.h"
72 #include "opt_kdb.h"
73 #include "opt_gdb.h"
74 #include "opt_ddb.h"
75 
76 
77 #ifndef DCONS_POLL_HZ
78 #define DCONS_POLL_HZ	25
79 #endif
80 
81 #ifndef DCONS_POLL_IDLE
82 #define DCONS_POLL_IDLE	256
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 KLD_MODULE
94 static char bssbuf[DCONS_BUF_SIZE];	/* buf in bss */
95 #endif
96 
97 /* global data */
98 static struct dcons_global dg;
99 struct dcons_global *dcons_conf;
100 static int poll_hz = DCONS_POLL_HZ;
101 static u_int poll_idle = DCONS_POLL_HZ * DCONS_POLL_IDLE;
102 
103 static struct dcons_softc sc[DCONS_NPORT];
104 
105 static SYSCTL_NODE(_kern, OID_AUTO, dcons, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
106     "Dumb Console");
107 SYSCTL_INT(_kern_dcons, OID_AUTO, poll_hz, CTLFLAG_RW, &poll_hz, 0,
108 				"dcons polling rate");
109 
110 static int drv_init = 0;
111 static struct callout dcons_callout;
112 struct dcons_buf *dcons_buf;		/* for local dconschat */
113 
114 static void	dcons_timeout(void *);
115 static int	dcons_drv_init(int);
116 
117 static cn_probe_t	dcons_cnprobe;
118 static cn_init_t	dcons_cninit;
119 static cn_term_t	dcons_cnterm;
120 static cn_getc_t	dcons_cngetc;
121 static cn_putc_t	dcons_cnputc;
122 static cn_grab_t	dcons_cngrab;
123 static cn_ungrab_t	dcons_cnungrab;
124 
125 CONSOLE_DRIVER(dcons);
126 
127 #if defined(GDB)
128 static gdb_probe_f	dcons_dbg_probe;
129 static gdb_init_f	dcons_dbg_init;
130 static gdb_term_f	dcons_dbg_term;
131 static gdb_getc_f	dcons_dbg_getc;
132 static gdb_putc_f	dcons_dbg_putc;
133 
134 GDB_DBGPORT(dcons, dcons_dbg_probe, dcons_dbg_init, dcons_dbg_term,
135     dcons_dbg_getc, dcons_dbg_putc);
136 
137 extern struct gdb_dbgport *gdb_cur;
138 #endif
139 
140 static tsw_outwakeup_t dcons_outwakeup;
141 static tsw_free_t      dcons_free;
142 
143 static struct ttydevsw dcons_ttydevsw = {
144 	.tsw_flags      = TF_NOPREFIX,
145 	.tsw_outwakeup  = dcons_outwakeup,
146 	.tsw_free       = dcons_free,
147 };
148 
149 static int dcons_close_refs;
150 
151 #if (defined(GDB) || defined(DDB))
152 static int
153 dcons_check_break(struct dcons_softc *dc, int c)
154 {
155 
156 	if (c < 0)
157 		return (c);
158 
159 #ifdef GDB
160 	if ((dc->flags & DC_GDB) != 0 && gdb_cur == &dcons_gdb_dbgport)
161 		kdb_alt_break_gdb(c, &dc->brk_state);
162 	else
163 #endif
164 		kdb_alt_break(c, &dc->brk_state);
165 
166 	return (c);
167 }
168 #else
169 #define	dcons_check_break(dc, c)	(c)
170 #endif
171 
172 static int
173 dcons_os_checkc_nopoll(struct dcons_softc *dc)
174 {
175 	int c;
176 
177 	if (dg.dma_tag != NULL)
178 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_POSTREAD);
179 
180 	c = dcons_check_break(dc, dcons_checkc(dc));
181 
182 	if (dg.dma_tag != NULL)
183 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_PREREAD);
184 
185 	return (c);
186 }
187 
188 static int
189 dcons_os_checkc(struct dcons_softc *dc)
190 {
191 	EVENTHANDLER_INVOKE(dcons_poll, 0);
192 	return (dcons_os_checkc_nopoll(dc));
193 }
194 
195 static void
196 dcons_os_putc(struct dcons_softc *dc, int c)
197 {
198 	if (dg.dma_tag != NULL)
199 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_POSTWRITE);
200 
201 	dcons_putc(dc, c);
202 
203 	if (dg.dma_tag != NULL)
204 		bus_dmamap_sync(dg.dma_tag, dg.dma_map, BUS_DMASYNC_PREWRITE);
205 }
206 
207 static void
208 dcons_free(void *xsc __unused)
209 {
210 
211 	/* Our deferred free has arrived, now we're waiting for one fewer. */
212 	atomic_subtract_rel_int(&dcons_close_refs, 1);
213 }
214 
215 static void
216 dcons_outwakeup(struct tty *tp)
217 {
218 	struct dcons_softc *dc;
219 	char ch;
220 
221 	dc = tty_softc(tp);
222 
223 	while (ttydisc_getc(tp, &ch, sizeof ch) != 0)
224 		dcons_os_putc(dc, ch);
225 }
226 
227 static void
228 dcons_timeout(void *v)
229 {
230 	struct	tty *tp;
231 	struct dcons_softc *dc;
232 	int i, c, polltime;
233 
234 	for (i = 0; i < DCONS_NPORT; i ++) {
235 		dc = &sc[i];
236 		tp = dc->tty;
237 
238 		tty_lock(tp);
239 		while ((c = dcons_os_checkc_nopoll(dc)) != -1) {
240 			ttydisc_rint(tp, c, 0);
241 			poll_idle = 0;
242 		}
243 		ttydisc_rint_done(tp);
244 		tty_unlock(tp);
245 	}
246 	poll_idle++;
247 	polltime = hz;
248 	if (poll_idle <= (poll_hz * DCONS_POLL_IDLE))
249 		polltime /= poll_hz;
250 	callout_reset(&dcons_callout, polltime, dcons_timeout, tp);
251 }
252 
253 static void
254 dcons_cnprobe(struct consdev *cp)
255 {
256 	sprintf(cp->cn_name, "dcons");
257 #if DCONS_FORCE_CONSOLE
258 	cp->cn_pri = CN_REMOTE;
259 #else
260 	cp->cn_pri = CN_NORMAL;
261 #endif
262 }
263 
264 static void
265 dcons_cninit(struct consdev *cp)
266 {
267 	dcons_drv_init(0);
268 	cp->cn_arg = (void *)&sc[DCONS_CON]; /* share port0 with unit0 */
269 }
270 
271 static void
272 dcons_cnterm(struct consdev *cp)
273 {
274 }
275 
276 static void
277 dcons_cngrab(struct consdev *cp)
278 {
279 }
280 
281 static void
282 dcons_cnungrab(struct consdev *cp)
283 {
284 }
285 
286 static int
287 dcons_cngetc(struct consdev *cp)
288 {
289 	struct dcons_softc *dc = (struct dcons_softc *)cp->cn_arg;
290 	return (dcons_os_checkc(dc));
291 }
292 
293 static void
294 dcons_cnputc(struct consdev *cp, int c)
295 {
296 	struct dcons_softc *dc = (struct dcons_softc *)cp->cn_arg;
297 	dcons_os_putc(dc, c);
298 }
299 
300 static int
301 dcons_drv_init(int stage)
302 {
303 #if defined(__i386__) || defined(__amd64__)
304 	quad_t addr, size;
305 #endif
306 
307 	if (drv_init)
308 		return(drv_init);
309 
310 	drv_init = -1;
311 
312 	bzero(&dg, sizeof(dg));
313 	dcons_conf = &dg;
314 	dg.cdev = &dcons_consdev;
315 	dg.buf = NULL;
316 	dg.size = DCONS_BUF_SIZE;
317 
318 #if defined(__i386__) || defined(__amd64__)
319 	if (getenv_quad("dcons.addr", &addr) > 0 &&
320 	    getenv_quad("dcons.size", &size) > 0) {
321 #ifdef __i386__
322 		vm_paddr_t pa;
323 		/*
324 		 * Allow read/write access to dcons buffer.
325 		 */
326 		for (pa = trunc_page(addr); pa < addr + size; pa += PAGE_SIZE)
327 			pmap_ksetrw(PMAP_MAP_LOW + pa);
328 		invltlb();
329 #endif
330 		/* XXX P to V */
331 #ifdef __amd64__
332 		dg.buf = (struct dcons_buf *)(vm_offset_t)(KERNBASE + addr);
333 #else /* __i386__ */
334 		dg.buf = (struct dcons_buf *)((vm_offset_t)PMAP_MAP_LOW +
335 		    addr);
336 #endif
337 		dg.size = size;
338 		if (dcons_load_buffer(dg.buf, dg.size, sc) < 0)
339 			dg.buf = NULL;
340 	}
341 #endif
342 	if (dg.buf != NULL)
343 		goto ok;
344 
345 #ifndef KLD_MODULE
346 	if (stage == 0) { /* XXX or cold */
347 		/*
348 		 * DCONS_FORCE_CONSOLE == 1 and statically linked.
349 		 * called from cninit(). can't use contigmalloc yet .
350 		 */
351 		dg.buf = (struct dcons_buf *) bssbuf;
352 		dcons_init(dg.buf, dg.size, sc);
353 	} else
354 #endif
355 	{
356 		/*
357 		 * DCONS_FORCE_CONSOLE == 0 or kernel module case.
358 		 * if the module is loaded after boot,
359 		 * bssbuf could be non-continuous.
360 		 */
361 		dg.buf = (struct dcons_buf *) contigmalloc(dg.size,
362 			M_DEVBUF, 0, 0x10000, 0xffffffff, PAGE_SIZE, 0ul);
363 		if (dg.buf == NULL)
364 			return (-1);
365 		dcons_init(dg.buf, dg.size, sc);
366 	}
367 
368 ok:
369 	dcons_buf = dg.buf;
370 
371 	drv_init = 1;
372 
373 	return 0;
374 }
375 
376 
377 static int
378 dcons_attach_port(int port, char *name, int flags)
379 {
380 	struct dcons_softc *dc;
381 	struct tty *tp;
382 
383 	dc = &sc[port];
384 	tp = tty_alloc(&dcons_ttydevsw, dc);
385 	dc->flags = flags;
386 	dc->tty   = tp;
387 	tty_init_console(tp, 0);
388 	tty_makedev(tp, NULL, "%s", name);
389 	return(0);
390 }
391 
392 static int
393 dcons_attach(void)
394 {
395 	int polltime;
396 
397 	dcons_attach_port(DCONS_CON, "dcons", 0);
398 	dcons_attach_port(DCONS_GDB, "dgdb", DC_GDB);
399 	callout_init(&dcons_callout, 1);
400 	polltime = hz / poll_hz;
401 	callout_reset(&dcons_callout, polltime, dcons_timeout, NULL);
402 	return(0);
403 }
404 
405 static int
406 dcons_detach(int port)
407 {
408 	struct	tty *tp;
409 	struct dcons_softc *dc;
410 
411 	dc = &sc[port];
412 	tp = dc->tty;
413 
414 	/* tty_rel_gone() schedules a deferred free callback, count it. */
415 	atomic_add_int(&dcons_close_refs, 1);
416 	tty_lock(tp);
417 	tty_rel_gone(tp);
418 
419 	return(0);
420 }
421 
422 static int
423 dcons_modevent(module_t mode, int type, void *data)
424 {
425 	int err = 0, ret;
426 
427 	switch (type) {
428 	case MOD_LOAD:
429 		ret = dcons_drv_init(1);
430 		if (ret != -1)
431 			dcons_attach();
432 		if (ret == 0) {
433 			dcons_cnprobe(&dcons_consdev);
434 			dcons_cninit(&dcons_consdev);
435 			cnadd(&dcons_consdev);
436 		}
437 		break;
438 	case MOD_UNLOAD:
439 		printf("dcons: unload\n");
440 		if (drv_init == 1) {
441 			callout_stop(&dcons_callout);
442 			cnremove(&dcons_consdev);
443 			dcons_detach(DCONS_CON);
444 			dcons_detach(DCONS_GDB);
445 			dg.buf->magic = 0;
446 
447 			contigfree(dg.buf, DCONS_BUF_SIZE, M_DEVBUF);
448 		}
449 
450 		/* Wait for tty deferred free callbacks to complete. */
451 		while (atomic_load_acq_int(&dcons_close_refs) > 0)
452                         pause_sbt("dcunld", mstosbt(50), mstosbt(10), 0);
453 		break;
454 	case MOD_SHUTDOWN:
455 #if 0		/* Keep connection after halt */
456 		dg.buf->magic = 0;
457 #endif
458 		break;
459 	default:
460 		err = EOPNOTSUPP;
461 		break;
462 	}
463 	return(err);
464 }
465 
466 #if defined(GDB)
467 /* Debugger interface */
468 
469 static int
470 dcons_os_getc(struct dcons_softc *dc)
471 {
472 	int c;
473 
474 	while ((c = dcons_os_checkc(dc)) == -1);
475 
476 	return (c & 0xff);
477 }
478 
479 static int
480 dcons_dbg_probe(void)
481 {
482 	int dcons_gdb;
483 
484 	if (getenv_int("dcons_gdb", &dcons_gdb) == 0)
485 		return (-1);
486 	return (dcons_gdb);
487 }
488 
489 static void
490 dcons_dbg_init(void)
491 {
492 }
493 
494 static void
495 dcons_dbg_term(void)
496 {
497 }
498 
499 static void
500 dcons_dbg_putc(int c)
501 {
502 	struct dcons_softc *dc = &sc[DCONS_GDB];
503 	dcons_os_putc(dc, c);
504 }
505 
506 static int
507 dcons_dbg_getc(void)
508 {
509 	struct dcons_softc *dc = &sc[DCONS_GDB];
510 	return (dcons_os_getc(dc));
511 }
512 #endif
513 
514 DEV_MODULE(dcons, dcons_modevent, NULL);
515 MODULE_VERSION(dcons, DCONS_VERSION);
516