freebsd-skq/sys/dev/cfe/cfe_console.c
Kyle Evans 23d5326823 tty: convert tty_lock_assert to tty_assert_locked to hide lock type
A later change, currently being iterated on in D24459, will in-fact change
the lock type to an sx so that TTY drivers can sleep on it if they need to.
Committing this ahead of time to make the review in question a little more
palatable.

tty_lock_assert() is unfortunately still needed for now in two places to
make sure that the tty lock has not been recursed upon, for those scenarios
where it's supplied by the TTY driver and possibly a mutex that is allowed
to recurse.

Suggested by:	markj
2020-04-17 18:34:49 +00:00

229 lines
4.7 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2007 Bruce M. Simpson.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/kdb.h>
#include <sys/kernel.h>
#include <sys/priv.h>
#include <sys/systm.h>
#include <sys/types.h>
#include <sys/conf.h>
#include <sys/cons.h>
#include <sys/consio.h>
#include <sys/tty.h>
#include <dev/cfe/cfe_api.h>
#include <dev/cfe/cfe_error.h>
#include <ddb/ddb.h>
#ifndef CFECONS_POLL_HZ
#define CFECONS_POLL_HZ 4
#endif
#define CFEBURSTLEN 128 /* max number of bytes to write in one chunk */
static tsw_open_t cfe_tty_open;
static tsw_close_t cfe_tty_close;
static tsw_outwakeup_t cfe_tty_outwakeup;
static struct ttydevsw cfe_ttydevsw = {
.tsw_flags = TF_NOPREFIX,
.tsw_open = cfe_tty_open,
.tsw_close = cfe_tty_close,
.tsw_outwakeup = cfe_tty_outwakeup,
};
static int conhandle = -1;
/* XXX does cfe have to poll? */
static int polltime;
static struct callout cfe_timer;
#if defined(KDB)
static int alt_break_state;
#endif
static void cfe_timeout(void *);
static cn_probe_t cfe_cnprobe;
static cn_init_t cfe_cninit;
static cn_term_t cfe_cnterm;
static cn_getc_t cfe_cngetc;
static cn_putc_t cfe_cnputc;
static cn_grab_t cfe_cngrab;
static cn_ungrab_t cfe_cnungrab;
CONSOLE_DRIVER(cfe);
static void
cn_drvinit(void *unused)
{
struct tty *tp;
if (cfe_consdev.cn_pri != CN_DEAD &&
cfe_consdev.cn_name[0] != '\0') {
tp = tty_alloc(&cfe_ttydevsw, NULL);
callout_init_mtx(&cfe_timer, tty_getlock(tp), 0);
tty_makedev(tp, NULL, "cfecons");
}
}
static int
cfe_tty_open(struct tty *tp)
{
polltime = hz / CFECONS_POLL_HZ;
if (polltime < 1)
polltime = 1;
callout_reset(&cfe_timer, polltime, cfe_timeout, tp);
return (0);
}
static void
cfe_tty_close(struct tty *tp)
{
callout_stop(&cfe_timer);
}
static void
cfe_tty_outwakeup(struct tty *tp)
{
int len, written, rc;
u_char buf[CFEBURSTLEN];
for (;;) {
len = ttydisc_getc(tp, buf, sizeof buf);
if (len == 0)
break;
written = 0;
while (written < len) {
rc = cfe_write(conhandle, &buf[written], len - written);
if (rc < 0)
break;
written += rc;
}
}
}
static void
cfe_timeout(void *v)
{
struct tty *tp;
int c;
tp = (struct tty *)v;
tty_assert_locked(tp);
while ((c = cfe_cngetc(NULL)) != -1)
ttydisc_rint(tp, c, 0);
ttydisc_rint_done(tp);
callout_reset(&cfe_timer, polltime, cfe_timeout, tp);
}
static void
cfe_cnprobe(struct consdev *cp)
{
conhandle = cfe_getstdhandle(CFE_STDHANDLE_CONSOLE);
if (conhandle < 0) {
cp->cn_pri = CN_DEAD;
return;
}
/* XXX */
if (bootverbose) {
char *bootmsg = "Using CFE firmware console.\n";
int i;
for (i = 0; i < strlen(bootmsg); i++)
cfe_cnputc(cp, bootmsg[i]);
}
cp->cn_pri = CN_LOW;
}
static void
cfe_cninit(struct consdev *cp)
{
strcpy(cp->cn_name, "cfecons");
}
static void
cfe_cnterm(struct consdev *cp)
{
}
static void
cfe_cngrab(struct consdev *cp)
{
}
static void
cfe_cnungrab(struct consdev *cp)
{
}
static int
cfe_cngetc(struct consdev *cp)
{
unsigned char ch;
if (cfe_read(conhandle, &ch, 1) == 1) {
#if defined(KDB)
kdb_alt_break(ch, &alt_break_state);
#endif
return (ch);
}
return (-1);
}
static void
cfe_cnputc(struct consdev *cp, int c)
{
char cbuf;
if (c == '\n')
cfe_cnputc(cp, '\r');
cbuf = c;
while (cfe_write(conhandle, &cbuf, 1) == 0)
continue;
}
SYSINIT(cndev, SI_SUB_CONFIGURE, SI_ORDER_MIDDLE, cn_drvinit, NULL);