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
92static char bssbuf[DCONS_BUF_SIZE];	/* buf in bss */
93#endif
94
95/* global data */
96static struct dcons_global dg;
97struct dcons_global *dcons_conf;
98static int poll_hz = DCONS_POLL_HZ;
99static u_int poll_idle = DCONS_POLL_HZ * DCONS_POLL_IDLE;
100
101static struct dcons_softc sc[DCONS_NPORT];
102
103static SYSCTL_NODE(_kern, OID_AUTO, dcons, CTLFLAG_RD | CTLFLAG_MPSAFE, 0,
104    "Dumb Console");
105SYSCTL_INT(_kern_dcons, OID_AUTO, poll_hz, CTLFLAG_RW, &poll_hz, 0,
106				"dcons polling rate");
107
108static int drv_init = 0;
109static struct callout dcons_callout;
110struct dcons_buf *dcons_buf;		/* for local dconschat */
111
112static void	dcons_timeout(void *);
113static int	dcons_drv_init(int);
114
115static cn_probe_t	dcons_cnprobe;
116static cn_init_t	dcons_cninit;
117static cn_term_t	dcons_cnterm;
118static cn_getc_t	dcons_cngetc;
119static cn_putc_t	dcons_cnputc;
120static cn_grab_t	dcons_cngrab;
121static cn_ungrab_t	dcons_cnungrab;
122
123CONSOLE_DRIVER(dcons);
124
125#if defined(GDB)
126static gdb_probe_f	dcons_dbg_probe;
127static gdb_init_f	dcons_dbg_init;
128static gdb_term_f	dcons_dbg_term;
129static gdb_getc_f	dcons_dbg_getc;
130static gdb_putc_f	dcons_dbg_putc;
131
132GDB_DBGPORT(dcons, dcons_dbg_probe, dcons_dbg_init, dcons_dbg_term,
133    dcons_dbg_getc, dcons_dbg_putc);
134
135extern struct gdb_dbgport *gdb_cur;
136#endif
137
138static tsw_outwakeup_t dcons_outwakeup;
139static tsw_free_t      dcons_free;
140
141static struct ttydevsw dcons_ttydevsw = {
142	.tsw_flags      = TF_NOPREFIX,
143	.tsw_outwakeup  = dcons_outwakeup,
144	.tsw_free       = dcons_free,
145};
146
147static int dcons_close_refs;
148
149#if (defined(GDB) || defined(DDB))
150static int
151dcons_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
170static int
171dcons_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
186static int
187dcons_os_checkc(struct dcons_softc *dc)
188{
189	EVENTHANDLER_INVOKE(dcons_poll, 0);
190	return (dcons_os_checkc_nopoll(dc));
191}
192
193static void
194dcons_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
205static void
206dcons_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
213static void
214dcons_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
225static void
226dcons_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
251static void
252dcons_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
262static void
263dcons_cninit(struct consdev *cp)
264{
265	dcons_drv_init(0);
266	cp->cn_arg = (void *)&sc[DCONS_CON]; /* share port0 with unit0 */
267}
268
269static void
270dcons_cnterm(struct consdev *cp)
271{
272}
273
274static void
275dcons_cngrab(struct consdev *cp)
276{
277}
278
279static void
280dcons_cnungrab(struct consdev *cp)
281{
282}
283
284static int
285dcons_cngetc(struct consdev *cp)
286{
287	struct dcons_softc *dc = (struct dcons_softc *)cp->cn_arg;
288	return (dcons_os_checkc(dc));
289}
290
291static void
292dcons_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
298static int
299dcons_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
366ok:
367	dcons_buf = dg.buf;
368
369	drv_init = 1;
370
371	return 0;
372}
373
374
375static int
376dcons_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
390static int
391dcons_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
403static int
404dcons_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
420static int
421dcons_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			contigfree(dg.buf, DCONS_BUF_SIZE, 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
467static int
468dcons_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
477static int
478dcons_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
487static void
488dcons_dbg_init(void)
489{
490}
491
492static void
493dcons_dbg_term(void)
494{
495}
496
497static void
498dcons_dbg_putc(int c)
499{
500	struct dcons_softc *dc = &sc[DCONS_GDB];
501	dcons_os_putc(dc, c);
502}
503
504static int
505dcons_dbg_getc(void)
506{
507	struct dcons_softc *dc = &sc[DCONS_GDB];
508	return (dcons_os_getc(dc));
509}
510#endif
511
512DEV_MODULE(dcons, dcons_modevent, NULL);
513MODULE_VERSION(dcons, DCONS_VERSION);
514