Add dumb console driver and related bits.

dcons(4): very simple console and gdb port driver
dcons_crom(4): FireWire attachment
dconschat(8): User interface to dcons

Tested with: i386, i386-PAE, and sparc64.

1 files changed, 648 insertions, 0 deletions

diff --git a/sys/dev/dcons/dcons.c b/sys/dev/dcons/dcons.c
new file mode 100644
index 0000000..4cea5ca
--- /dev/null
+++ b/sys/dev/dcons/dcons.c
@@ -0,0 +1,648 @@
+/*
+ * Copyright (C) 2003
+ * 	Hidetoshi Shimokawa. 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.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *
+ *	This product includes software developed by Hidetoshi Shimokawa.
+ *
+ * 4. Neither the name of the author nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
+ * 
+ * $Id: dcons.c,v 1.65 2003/10/24 03:24:55 simokawa Exp $
+ * $FreeBSD$
+ */
+
+#include <sys/param.h>
+#include <sys/kernel.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 <sys/malloc.h>
+#include <sys/proc.h>
+#include <sys/ucred.h>
+
+#include <machine/bus.h>
+
+#include <dev/dcons/dcons.h>
+
+#include <ddb/ddb.h>
+#include <sys/reboot.h>
+
+#include <sys/sysctl.h>
+
+#include "opt_ddb.h"
+#include "opt_comconsole.h"
+#include "opt_dcons.h"
+
+#ifndef DCONS_POLL_HZ
+#define DCONS_POLL_HZ	100
+#endif
+
+#ifndef DCONS_BUF_SIZE
+#define DCONS_BUF_SIZE (16*1024)
+#endif
+
+#ifndef DCONS_FORCE_CONSOLE
+#define DCONS_FORCE_CONSOLE	0	/* mostly for FreeBSD-4 */
+#endif
+
+#ifndef DCONS_FORCE_GDB
+#define DCONS_FORCE_GDB	1
+#endif
+
+#if __FreeBSD_version >= 500101
+#define CONS_NODEV	1	/* for latest current */
+static struct consdev gdbconsdev;
+#endif
+
+#define	CDEV_MAJOR	184
+
+static d_open_t		dcons_open;
+static d_close_t	dcons_close;
+static d_ioctl_t	dcons_ioctl;
+
+static struct cdevsw dcons_cdevsw = {
+#if __FreeBSD_version >= 500104
+	.d_open =	dcons_open,
+	.d_close =	dcons_close,
+	.d_read =	ttyread,
+	.d_write =	ttywrite,
+	.d_ioctl =	dcons_ioctl,
+	.d_poll =	ttypoll,
+	.d_name =	"dcons",
+	.d_maj =	CDEV_MAJOR,
+#else
+	/* open */	dcons_open,
+	/* close */	dcons_close,
+	/* read */	ttyread,
+	/* write */	ttywrite,
+	/* ioctl */	dcons_ioctl,
+	/* poll */	ttypoll,
+	/* mmap */	nommap,
+	/* strategy */	nostrategy,
+	/* name */	"dcons",
+	/* major */	CDEV_MAJOR,
+	/* dump */	nodump,
+	/* psize */	nopsize,
+	/* flags */	0,
+#endif
+};
+
+#ifndef KLD_MODULE
+static char bssbuf[DCONS_BUF_SIZE];	/* buf in bss */
+#endif
+struct dcons_buf *dcons_buf;
+size_t dcons_bufsize;
+bus_dma_tag_t dcons_dma_tag = NULL;
+bus_dmamap_t dcons_dma_map = NULL;
+
+static int poll_hz = DCONS_POLL_HZ;
+SYSCTL_NODE(_kern, OID_AUTO, dcons, CTLFLAG_RD, 0, "Dumb Console");
+SYSCTL_INT(_kern_dcons, OID_AUTO, poll_hz, CTLFLAG_RW, &poll_hz, 0,
+				"dcons polling rate");
+
+static int drv_init = 0;
+static struct callout dcons_callout;
+
+/* per device data */
+static struct dcons_softc {
+	dev_t dev;
+	struct dcons_ch	o, i;
+	int brk_state;
+#define DC_GDB	1
+	int flags;
+} sc[DCONS_NPORT];
+static void	dcons_tty_start(struct tty *);
+static int	dcons_tty_param(struct tty *, struct termios *);
+static void	dcons_timeout(void *);
+static int	dcons_drv_init(int);
+static int	dcons_getc(struct dcons_softc *);
+static int	dcons_checkc(struct dcons_softc *);
+static void	dcons_putc(struct dcons_softc *, int);
+
+static cn_probe_t	dcons_cnprobe;
+static cn_init_t	dcons_cninit;
+static cn_getc_t	dcons_cngetc;
+static cn_checkc_t 	dcons_cncheckc;
+static cn_putc_t	dcons_cnputc;
+
+CONS_DRIVER(dcons, dcons_cnprobe, dcons_cninit, NULL, dcons_cngetc,
+    dcons_cncheckc, dcons_cnputc, NULL);
+
+#if __FreeBSD_version < 500000
+#define THREAD	proc
+#else
+#define THREAD	thread
+#endif
+
+static int
+dcons_open(dev_t dev, int flag, int mode, struct THREAD *td)
+{
+	struct tty *tp;
+	int unit, error, s;
+
+	unit = minor(dev);
+	if (unit != 0)
+		return (ENXIO);
+
+	tp = dev->si_tty = ttymalloc(dev->si_tty);
+	tp->t_oproc = dcons_tty_start;
+	tp->t_param = dcons_tty_param;
+	tp->t_stop = nottystop;
+	tp->t_dev = dev;
+
+	error = 0;
+
+	s = spltty();
+	if ((tp->t_state & TS_ISOPEN) == 0) {
+		tp->t_state |= TS_CARR_ON;
+		ttychars(tp);
+		tp->t_iflag = TTYDEF_IFLAG;
+		tp->t_oflag = TTYDEF_OFLAG;
+		tp->t_cflag = TTYDEF_CFLAG|CLOCAL;
+		tp->t_lflag = TTYDEF_LFLAG;
+		tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
+		ttsetwater(tp);
+	} else if ((tp->t_state & TS_XCLUDE) && suser(td)) {
+		splx(s);
+		return (EBUSY);
+	}
+	splx(s);
+
+	error = (*linesw[tp->t_line].l_open)(dev, tp);
+
+	return (error);
+}
+
+static int
+dcons_close(dev_t dev, int flag, int mode, struct THREAD *td)
+{
+	int	unit;
+	struct	tty *tp;
+
+	unit = minor(dev);
+	if (unit != 0)
+		return (ENXIO);
+
+	tp = dev->si_tty;
+	if (tp->t_state & TS_ISOPEN) {
+		(*linesw[tp->t_line].l_close)(tp, flag);
+		ttyclose(tp);
+	}
+
+	return (0);
+}
+
+static int
+dcons_ioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct THREAD *td)
+{
+	int	unit;
+	struct	tty *tp;
+	int	error;
+
+	unit = minor(dev);
+	if (unit != 0)
+		return (ENXIO);
+
+	tp = dev->si_tty;
+	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, td);
+	if (error != ENOIOCTL)
+		return (error);
+
+	error = ttioctl(tp, cmd, data, flag);
+	if (error != ENOIOCTL)
+		return (error);
+
+	return (ENOTTY);
+}
+
+static int
+dcons_tty_param(struct tty *tp, struct termios *t)
+{
+	tp->t_ispeed = t->c_ispeed;
+	tp->t_ospeed = t->c_ospeed;
+	tp->t_cflag = t->c_cflag;
+	return 0;
+}
+
+static void
+dcons_tty_start(struct tty *tp)
+{
+	struct dcons_softc *dc;
+	int s;
+
+	dc = (struct dcons_softc *)tp->t_dev->si_drv1;
+	s = spltty();
+	if (tp->t_state & (TS_TIMEOUT | TS_TTSTOP)) {
+		ttwwakeup(tp);
+		return;
+	}
+
+	tp->t_state |= TS_BUSY;
+	while (tp->t_outq.c_cc != 0)
+		dcons_putc(dc, getc(&tp->t_outq));
+	tp->t_state &= ~TS_BUSY;
+
+	ttwwakeup(tp);
+	splx(s);
+}
+
+static void
+dcons_timeout(void *v)
+{
+	struct	tty *tp;
+	struct dcons_softc *dc;
+	int i, c, polltime;
+
+	for (i = 0; i < DCONS_NPORT; i ++) {
+		dc = &sc[i];
+		tp = dc->dev->si_tty;
+		while ((c = dcons_checkc(dc)) != -1)
+			if (tp->t_state & TS_ISOPEN)
+				(*linesw[tp->t_line].l_rint)(c, tp);
+	}
+	polltime = hz / poll_hz;
+	if (polltime < 1)
+		polltime = 1;
+	callout_reset(&dcons_callout, polltime, dcons_timeout, tp);
+}
+
+static void
+dcons_cnprobe(struct consdev *cp)
+{
+#if __FreeBSD_version >= 501109
+	sprintf(cp->cn_name, "dcons");
+#else
+	cp->cn_dev = makedev(CDEV_MAJOR, DCONS_CON);
+#endif
+#if DCONS_FORCE_CONSOLE
+	cp->cn_pri = CN_REMOTE;
+#else
+	cp->cn_pri = CN_NORMAL;
+#endif
+}
+
+static void
+dcons_cninit(struct consdev *cp)
+{
+	dcons_drv_init(0);
+#if CONS_NODEV
+	cp->cn_arg
+#else
+	cp->cn_dev->si_drv1
+#endif
+		= (void *)&sc[DCONS_CON]; /* share port0 with unit0 */
+}
+
+#if CONS_NODEV
+static int
+dcons_cngetc(struct consdev *cp)
+{
+	return(dcons_getc((struct dcons_softc *)cp->cn_arg));
+}
+static int
+dcons_cncheckc(struct consdev *cp)
+{
+	return(dcons_checkc((struct dcons_softc *)cp->cn_arg)); 
+}
+static void
+dcons_cnputc(struct consdev *cp, int c)
+{
+	dcons_putc((struct dcons_softc *)cp->cn_arg, c);
+}
+#else
+static int
+dcons_cngetc(dev_t dev)
+{
+	return(dcons_getc((struct dcons_softc *)dev->si_drv1));
+}
+static int
+dcons_cncheckc(dev_t dev)
+{
+	return(dcons_checkc((struct dcons_softc *)dev->si_drv1));
+}
+static void
+dcons_cnputc(dev_t dev, int c)
+{
+	dcons_putc((struct dcons_softc *)dev->si_drv1, c);
+}
+#endif
+
+static int
+dcons_getc(struct dcons_softc *dc)
+{
+	int c;
+
+	while ((c = dcons_checkc(dc)) == -1);
+
+	return (c & 0xff);
+}
+
+static int
+dcons_checkc(struct dcons_softc *dc)
+{
+	unsigned char c;
+	u_int32_t ptr, pos, gen, next_gen;
+	struct dcons_ch *ch;
+
+	ch = &dc->i;
+
+	if (dcons_dma_tag != NULL)
+		bus_dmamap_sync(dcons_dma_tag, dcons_dma_map,
+						BUS_DMASYNC_POSTREAD);
+	ptr = ntohl(*ch->ptr);
+	gen = ptr >> DCONS_GEN_SHIFT;
+	pos = ptr & DCONS_POS_MASK;
+	if (gen == ch->gen && pos == ch->pos)
+		return (-1);
+
+	next_gen = DCONS_NEXT_GEN(ch->gen);
+	/* XXX sanity check */
+	if ((gen != ch->gen && gen != next_gen)
+			|| (gen == ch->gen && pos < ch->pos)) {
+		/* generation skipped !! */
+		/* XXX discard */
+		ch->gen = gen;
+		ch->pos = pos;
+		return (-1);
+	}
+
+	c = ch->buf[ch->pos];
+	ch->pos ++;
+	if (ch->pos >= ch->size) {
+		ch->gen = next_gen;
+		ch->pos = 0;
+	}
+
+#if DDB && ALT_BREAK_TO_DEBUGGER
+	switch (dc->brk_state) {
+	case STATE1:
+		if (c == KEY_TILDE)
+			dc->brk_state = STATE2;
+		else
+			dc->brk_state = STATE0;
+		break;
+	case STATE2:
+		dc->brk_state = STATE0;
+		if (c == KEY_CTRLB) {
+#if DCONS_FORCE_GDB
+			if (dc->flags & DC_GDB)
+				boothowto |= RB_GDB;
+#endif
+			breakpoint();
+		}
+	}
+	if (c == KEY_CR)
+		dc->brk_state = STATE1;
+#endif
+	return (c);
+}
+
+static void
+dcons_putc(struct dcons_softc *dc, int c)
+{
+	struct dcons_ch *ch;
+
+	ch = &dc->o;
+
+	ch->buf[ch->pos] = c;
+	ch->pos ++;
+	if (ch->pos >= ch->size) {
+		ch->gen = DCONS_NEXT_GEN(ch->gen);
+		ch->pos = 0;
+	}
+	*ch->ptr = DCONS_MAKE_PTR(ch);
+	if (dcons_dma_tag != NULL)
+		bus_dmamap_sync(dcons_dma_tag, dcons_dma_map,
+						BUS_DMASYNC_PREWRITE);
+}
+
+static int
+dcons_init_port(int port, int offset, int size)
+{
+	int osize;
+	struct dcons_softc *dc;
+
+	dc = &sc[port];
+
+	osize = size * 3 / 4;
+
+	dc->o.size = osize;
+	dc->i.size = size - osize;
+	dc->o.buf = (char *)dcons_buf + offset;
+	dc->i.buf = dc->o.buf + osize;
+	dc->o.gen = dc->i.gen = 0;
+	dc->o.pos = dc->i.pos = 0;
+	dc->o.ptr = &dcons_buf->optr[port];
+	dc->i.ptr = &dcons_buf->iptr[port];
+	dc->brk_state = STATE0;
+	dcons_buf->osize[port] = htonl(osize);
+	dcons_buf->isize[port] = htonl(size - osize);
+	dcons_buf->ooffset[port] = htonl(offset);
+	dcons_buf->ioffset[port] = htonl(offset + osize);
+	dcons_buf->optr[port] = DCONS_MAKE_PTR(&dc->o);
+	dcons_buf->iptr[port] = DCONS_MAKE_PTR(&dc->i);
+
+	return(0);
+}
+
+static int
+dcons_drv_init(int stage)
+{
+	int size, size0, offset;
+
+	if (drv_init)
+		return(drv_init);
+
+	drv_init = -1;
+
+	dcons_bufsize = DCONS_BUF_SIZE;
+
+#ifndef KLD_MODULE
+	if (stage == 0) /* XXX or cold */
+		/*
+		 * DCONS_FORCE_CONSOLE == 1 and statically linked.
+		 * called from cninit(). can't use contigmalloc yet .
+		 */
+		dcons_buf = (struct dcons_buf *) bssbuf;
+	else
+#endif
+		/*
+		 * DCONS_FORCE_CONSOLE == 0 or kernel module case.
+		 * if the module is loaded after boot,
+		 * dcons_buf could be non-continuous.
+		 */ 
+		dcons_buf = (struct dcons_buf *) contigmalloc(dcons_bufsize,
+			M_DEVBUF, 0, 0x10000, 0xffffffff, PAGE_SIZE, 0ul);
+
+	offset = DCONS_HEADER_SIZE;
+	size = (dcons_bufsize - offset);
+	size0 = size * 3 / 4;
+
+	dcons_init_port(0, offset, size0);
+	offset += size0;
+	dcons_init_port(1, offset, size - size0);
+	dcons_buf->version = htonl(DCONS_VERSION);
+	dcons_buf->magic = ntohl(DCONS_MAGIC);
+
+#if DDB && DCONS_FORCE_GDB
+#if CONS_NODEV
+	gdbconsdev.cn_arg = (void *)&sc[DCONS_GDB];
+#if __FreeBSD_version >= 501109
+	sprintf(gdbconsdev.cn_name, "dgdb");
+#endif
+	gdb_arg = &gdbconsdev;
+#else
+	gdbdev = makedev(CDEV_MAJOR, DCONS_GDB);
+#endif
+	gdb_getc = dcons_cngetc;
+	gdb_putc = dcons_cnputc;
+#endif
+	drv_init = 1;
+
+	return 0;
+}
+
+
+static int
+dcons_attach_port(int port, char *name, int flags)
+{
+	struct dcons_softc *dc;
+	struct tty *tp;
+
+	dc = &sc[port];
+	dc->flags = flags;
+	dc->dev = make_dev(&dcons_cdevsw, port,
+			UID_ROOT, GID_WHEEL, 0600, name);
+	tp = ttymalloc(NULL);
+
+	dc->dev->si_drv1 = (void *)dc;
+	dc->dev->si_tty = tp;
+
+	tp->t_oproc = dcons_tty_start;
+	tp->t_param = dcons_tty_param;
+	tp->t_stop = nottystop;
+	tp->t_dev = dc->dev;
+
+	return(0);
+}
+
+static int
+dcons_attach(void)
+{
+	int polltime;
+
+	dcons_attach_port(DCONS_CON, "dcons", 0);
+	dcons_attach_port(DCONS_GDB, "dgdb", DC_GDB);
+#if __FreeBSD_version < 500000
+	callout_init(&dcons_callout);
+#else
+	callout_init(&dcons_callout, 0);
+#endif
+	polltime = hz / poll_hz;
+	if (polltime < 1)
+		polltime = 1;
+	callout_reset(&dcons_callout, polltime, dcons_timeout, NULL);
+	return(0);
+}
+
+static int
+dcons_detach(int port)
+{
+	struct	tty *tp;
+	struct dcons_softc *dc;
+
+	dc = &sc[port];
+
+	tp = dc->dev->si_tty;
+
+	if (tp->t_state & TS_ISOPEN) {
+		printf("dcons: still opened\n");
+		(*linesw[tp->t_line].l_close)(tp, 0);
+		tp->t_gen++;
+		ttyclose(tp);
+		ttwakeup(tp);
+		ttwwakeup(tp);
+	}
+	/* XXX
+	 * must wait until all device are closed.
+	 */
+	tsleep((void *)dc, PWAIT, "dcodtc", hz/4);
+	destroy_dev(dc->dev);
+
+	return(0);
+}
+
+
+/* cnXXX works only for FreeBSD-5 */
+static int
+dcons_modevent(module_t mode, int type, void *data)
+{
+	int err = 0, ret;
+
+	switch (type) {
+	case MOD_LOAD:
+		ret = dcons_drv_init(1);
+		dcons_attach();
+#if __FreeBSD_version >= 500000
+		if (ret == 0) {
+			dcons_cnprobe(&dcons_consdev);
+			dcons_cninit(&dcons_consdev);
+			cnadd(&dcons_consdev);
+		}
+#endif
+		break;
+	case MOD_UNLOAD:
+		printf("dcons: unload\n");
+		callout_stop(&dcons_callout);
+#if DDB && DCONS_FORCE_GDB
+#if CONS_NODEV
+		gdb_arg = NULL;
+#else
+		gdbdev = NODEV;
+#endif
+#endif
+#if __FreeBSD_version >= 500000
+		cnremove(&dcons_consdev);
+#endif
+		dcons_detach(DCONS_CON);
+		dcons_detach(DCONS_GDB);
+		dcons_buf->magic = 0;
+
+		contigfree(dcons_buf, DCONS_BUF_SIZE, M_DEVBUF);
+
+		break;
+	case MOD_SHUTDOWN:
+		break;
+	}
+	return(err);
+}
+
+DEV_MODULE(dcons, dcons_modevent, NULL);
+MODULE_VERSION(dcons, DCONS_VERSION);