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
94static char bssbuf[DCONS_BUF_SIZE];	/* buf in bss */
95#endif
96
97/* global data */
98static struct dcons_global dg;
99struct dcons_global *dcons_conf;
100static int poll_hz = DCONS_POLL_HZ;
101static u_int poll_idle = DCONS_POLL_HZ * DCONS_POLL_IDLE;
102
103static struct dcons_softc sc[DCONS_NPORT];
104
105static SYSCTL_NODE(_kern, OID_AUTO, dcons, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
106    "Dumb Console");
107SYSCTL_INT(_kern_dcons, OID_AUTO, poll_hz, CTLFLAG_RW, &poll_hz, 0,
108				"dcons polling rate");
109
110static int drv_init = 0;
111static struct callout dcons_callout;
112struct dcons_buf *dcons_buf;		/* for local dconschat */
113
114static void	dcons_timeout(void *);
115static int	dcons_drv_init(int);
116
117static cn_probe_t	dcons_cnprobe;
118static cn_init_t	dcons_cninit;
119static cn_term_t	dcons_cnterm;
120static cn_getc_t	dcons_cngetc;
121static cn_putc_t	dcons_cnputc;
122static cn_grab_t	dcons_cngrab;
123static cn_ungrab_t	dcons_cnungrab;
124
125CONSOLE_DRIVER(dcons);
126
127#if defined(GDB)
128static gdb_probe_f	dcons_dbg_probe;
129static gdb_init_f	dcons_dbg_init;
130static gdb_term_f	dcons_dbg_term;
131static gdb_getc_f	dcons_dbg_getc;
132static gdb_putc_f	dcons_dbg_putc;
133
134GDB_DBGPORT(dcons, dcons_dbg_probe, dcons_dbg_init, dcons_dbg_term,
135    dcons_dbg_getc, dcons_dbg_putc);
136
137extern struct gdb_dbgport *gdb_cur;
138#endif
139
140static tsw_outwakeup_t dcons_outwakeup;
141static tsw_free_t      dcons_free;
142
143static struct ttydevsw dcons_ttydevsw = {
144	.tsw_flags      = TF_NOPREFIX,
145	.tsw_outwakeup  = dcons_outwakeup,
146	.tsw_free       = dcons_free,
147};
148
149static int dcons_close_refs;
150
151#if (defined(GDB) || defined(DDB))
152static int
153dcons_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
172static int
173dcons_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
188static int
189dcons_os_checkc(struct dcons_softc *dc)
190{
191	EVENTHANDLER_INVOKE(dcons_poll, 0);
192	return (dcons_os_checkc_nopoll(dc));
193}
194
195static void
196dcons_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
207static void
208dcons_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
215static void
216dcons_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
227static void
228dcons_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
253static void
254dcons_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
264static void
265dcons_cninit(struct consdev *cp)
266{
267	dcons_drv_init(0);
268	cp->cn_arg = (void *)&sc[DCONS_CON]; /* share port0 with unit0 */
269}
270
271static void
272dcons_cnterm(struct consdev *cp)
273{
274}
275
276static void
277dcons_cngrab(struct consdev *cp)
278{
279}
280
281static void
282dcons_cnungrab(struct consdev *cp)
283{
284}
285
286static int
287dcons_cngetc(struct consdev *cp)
288{
289	struct dcons_softc *dc = (struct dcons_softc *)cp->cn_arg;
290	return (dcons_os_checkc(dc));
291}
292
293static void
294dcons_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
300static int
301dcons_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
368ok:
369	dcons_buf = dg.buf;
370
371	drv_init = 1;
372
373	return 0;
374}
375
376
377static int
378dcons_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
392static int
393dcons_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
405static int
406dcons_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
422static int
423dcons_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
469static int
470dcons_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
479static int
480dcons_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
489static void
490dcons_dbg_init(void)
491{
492}
493
494static void
495dcons_dbg_term(void)
496{
497}
498
499static void
500dcons_dbg_putc(int c)
501{
502	struct dcons_softc *dc = &sc[DCONS_GDB];
503	dcons_os_putc(dc, c);
504}
505
506static int
507dcons_dbg_getc(void)
508{
509	struct dcons_softc *dc = &sc[DCONS_GDB];
510	return (dcons_os_getc(dc));
511}
512#endif
513
514DEV_MODULE(dcons, dcons_modevent, NULL);
515MODULE_VERSION(dcons, DCONS_VERSION);
516