Add watchdog support for VIA south bridge chipset.

Tested on VT8251, VX900 but CX700, VX800, VX855 should works.

MFC after:	1 month
Sponsored by: NETASQ

2 files changed, 361 insertions, 0 deletions

diff --git a/sys/dev/viawd/viawd.c b/sys/dev/viawd/viawd.c
new file mode 100644
index 0000000..01648c4
--- /dev/null
+++ b/sys/dev/viawd/viawd.c
@@ -0,0 +1,286 @@
+/*-
+ * Copyright (c) 2011 Fabien Thomas <fthomas@FreeBSD.org>
+ * 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/kernel.h>
+#include <sys/module.h>
+#include <sys/systm.h>
+#include <sys/bus.h>
+#include <machine/bus.h>
+#include <sys/rman.h>
+#include <machine/resource.h>
+#include <sys/watchdog.h>
+
+#include <isa/isavar.h>
+#include <dev/pci/pcivar.h>
+
+#include "viawd.h"
+
+#define viawd_read_wd_4(sc, off) \
+	bus_space_read_4((sc)->wd_bst, (sc)->wd_bsh, (off))
+#define viawd_write_wd_4(sc, off, val) \
+	bus_space_write_4((sc)->wd_bst, (sc)->wd_bsh, (off), (val))
+
+static struct viawd_device viawd_devices[] = {
+	{ DEVICEID_VT8251, "VIA VT8251 watchdog timer" },
+	{ DEVICEID_CX700,  "VIA CX700 watchdog timer" },
+	{ DEVICEID_VX800,  "VIA VX800 watchdog timer" },
+	{ DEVICEID_VX855,  "VIA VX855 watchdog timer" },
+	{ DEVICEID_VX900,  "VIA VX900 watchdog timer" },
+	{ 0, NULL },
+};
+
+static devclass_t viawd_devclass;
+
+static device_t
+viawd_find(struct viawd_device **id_p)
+{
+	struct viawd_device *id;
+	device_t sb_dev = NULL;
+
+	/* Look for a supported VIA south bridge. */
+	for (id = viawd_devices; id->desc != NULL; ++id)
+		if ((sb_dev = pci_find_device(VENDORID_VIA, id->device)) != NULL)
+			break;
+
+	if (sb_dev == NULL)
+		return (NULL);
+
+	if (id_p != NULL)
+		*id_p = id;
+
+	return (sb_dev);
+}
+
+static void
+viawd_tmr_state(struct viawd_softc *sc, int enable)
+{
+	uint32_t reg;
+
+	reg = viawd_read_wd_4(sc, VIAWD_MEM_CTRL);
+	if (enable)
+		reg |= VIAWD_MEM_CTRL_TRIGGER | VIAWD_MEM_CTRL_ENABLE;
+	else
+		reg &= ~VIAWD_MEM_CTRL_ENABLE;
+	viawd_write_wd_4(sc, VIAWD_MEM_CTRL, reg);
+}
+
+static void
+viawd_tmr_set(struct viawd_softc *sc, unsigned int timeout)
+{
+
+	/* Keep value in range. */
+	if (timeout < VIAWD_MEM_COUNT_MIN)
+		timeout = VIAWD_MEM_COUNT_MIN;
+	else if (timeout > VIAWD_MEM_COUNT_MAX)
+		timeout = VIAWD_MEM_COUNT_MAX;
+
+	viawd_write_wd_4(sc, VIAWD_MEM_COUNT, timeout);
+	sc->timeout = timeout;
+}
+
+/*
+ * Watchdog event handler - called by the framework to enable or disable
+ * the watchdog or change the initial timeout value.
+ */
+static void
+viawd_event(void *arg, unsigned int cmd, int *error)
+{
+	struct viawd_softc *sc = arg;
+	unsigned int timeout;
+
+	/* Convert from power-of-two-ns to second. */
+	cmd &= WD_INTERVAL;
+	timeout = ((uint64_t)1 << cmd) / 1000000000;
+	if (cmd) {
+		if (timeout != sc->timeout)
+			viawd_tmr_set(sc, timeout);
+		viawd_tmr_state(sc, 1);
+		*error = 0;
+	} else
+		viawd_tmr_state(sc, 0);
+}
+
+static void
+viawd_identify(driver_t *driver, device_t parent)
+{
+	device_t dev;
+	device_t sb_dev;
+	struct viawd_device *id_p;
+
+	sb_dev = viawd_find(&id_p);
+	if (sb_dev == NULL)
+		return;
+
+	/* Good, add child to bus. */
+	if ((dev = device_find_child(parent, driver->name, 0)) == NULL)
+		dev = BUS_ADD_CHILD(parent, 0, driver->name, 0);
+
+	if (dev == NULL)
+		return;
+
+	device_set_desc_copy(dev, id_p->desc);
+}
+
+static int
+viawd_probe(device_t dev)
+{
+
+	/* Do not claim some ISA PnP device by accident. */
+	if (isa_get_logicalid(dev) != 0)
+		return (ENXIO);
+	return (0);
+}
+
+static int
+viawd_attach(device_t dev)
+{
+	device_t sb_dev;
+	struct viawd_softc *sc;
+	struct viawd_device *id_p;
+	uint32_t pmbase, reg;
+
+	sc = device_get_softc(dev);
+	sc->dev = dev;
+
+	sb_dev = viawd_find(&id_p);
+	if (sb_dev == NULL) {
+		device_printf(dev, "Can not find watchdog device.\n");
+		goto fail;
+	}
+	sc->sb_dev = sb_dev;
+
+	/* Get watchdog memory base. */
+	pmbase = pci_read_config(sb_dev, VIAWD_CONFIG_BASE, 4);
+	if (pmbase == 0) {
+		device_printf(dev,
+		    "Watchdog disabled in BIOS or hardware\n");
+		goto fail;
+	}
+
+	/* Allocate I/O register space. */
+	sc->wd_rid = 0;
+	sc->wd_res = bus_alloc_resource(dev, SYS_RES_MEMORY, &sc->wd_rid,
+	    pmbase, pmbase + VIAWD_MEM_LEN - 1, VIAWD_MEM_LEN,
+	    RF_ACTIVE | RF_SHAREABLE);
+	if (sc->wd_res == NULL) {
+		device_printf(dev, "Unable to map watchdog memory\n");
+		goto fail;
+	}
+	sc->wd_bst = rman_get_bustag(sc->wd_res);
+	sc->wd_bsh = rman_get_bushandle(sc->wd_res);
+
+	/* Check if watchdog fired last boot. */
+	reg = viawd_read_wd_4(sc, VIAWD_MEM_CTRL);
+	if (reg & VIAWD_MEM_CTRL_FIRED) {
+		device_printf(dev,
+		    "ERROR: watchdog rebooted the system\n");
+		/* Reset bit state. */
+		viawd_write_wd_4(sc, VIAWD_MEM_CTRL, reg);
+	}
+
+	/* Register the watchdog event handler. */
+	sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, viawd_event, sc, 0);
+
+	return (0);
+fail:
+	if (sc->wd_res != NULL)
+		bus_release_resource(dev, SYS_RES_MEMORY,
+		    sc->wd_rid, sc->wd_res);
+	return (ENXIO);
+}
+
+static int
+viawd_detach(device_t dev)
+{
+	struct viawd_softc *sc;
+	uint32_t reg;
+
+	sc = device_get_softc(dev);
+
+	/* Deregister event handler. */
+	if (sc->ev_tag != NULL)
+		EVENTHANDLER_DEREGISTER(watchdog_list, sc->ev_tag);
+	sc->ev_tag = NULL;
+
+	/*
+	 * Do not stop the watchdog on shutdown if active but bump the
+	 * timer to avoid spurious reset.
+	 */
+	reg = viawd_read_wd_4(sc, VIAWD_MEM_CTRL);
+	if (reg & VIAWD_MEM_CTRL_ENABLE) {
+		viawd_tmr_set(sc, VIAWD_TIMEOUT_SHUTDOWN);
+		viawd_tmr_state(sc, 1);
+		device_printf(dev,
+		    "Keeping watchog alive during shutdown for %d seconds\n",
+		    VIAWD_TIMEOUT_SHUTDOWN);
+	}
+
+	if (sc->wd_res != NULL)
+		bus_release_resource(sc->dev, SYS_RES_MEMORY,
+		    sc->wd_rid, sc->wd_res);
+
+	return (0);
+}
+
+static device_method_t viawd_methods[] = {
+	DEVMETHOD(device_identify, viawd_identify),
+	DEVMETHOD(device_probe,	viawd_probe),
+	DEVMETHOD(device_attach, viawd_attach),
+	DEVMETHOD(device_detach, viawd_detach),
+	DEVMETHOD(device_shutdown, viawd_detach),
+	{0,0}
+};
+
+static driver_t viawd_driver = {
+	"viawd",
+	viawd_methods,
+	sizeof(struct viawd_softc),
+};
+
+static int
+viawd_modevent(module_t mode, int type, void *data)
+{
+	int error = 0;
+
+	switch (type) {
+	case MOD_LOAD:
+		printf("viawd module loaded\n");
+		break;
+	case MOD_UNLOAD:
+		printf("viawd module unloaded\n");
+		break;
+	case MOD_SHUTDOWN:
+		printf("viawd module shutting down\n");
+		break;
+	}
+	return (error);
+}
+
+DRIVER_MODULE(viawd, isa, viawd_driver, viawd_devclass, viawd_modevent, NULL);
diff --git a/sys/dev/viawd/viawd.h b/sys/dev/viawd/viawd.h
new file mode 100644
index 0000000..cc90b41
--- /dev/null
+++ b/sys/dev/viawd/viawd.h
@@ -0,0 +1,75 @@
+/*-
+ * Copyright (c) 2011 Fabien Thomas <fthomas@FreeBSD.org>
+ * 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _VIAWD_H_
+#define _VIAWD_H_
+
+struct viawd_device {
+	uint16_t		device;
+	char			*desc;
+};
+
+struct viawd_softc {
+	device_t		dev;
+	device_t		sb_dev;
+
+	int			wd_rid;
+	struct resource		*wd_res;
+	bus_space_tag_t		wd_bst;
+	bus_space_handle_t	wd_bsh;
+
+	eventhandler_tag	ev_tag;
+	unsigned int		timeout;
+};
+
+#define VENDORID_VIA		0x1106
+#define DEVICEID_VT8251		0x3287
+#define DEVICEID_CX700		0x8324
+#define DEVICEID_VX800		0x8353
+#define DEVICEID_VX855		0x8409
+#define DEVICEID_VX900		0x8410
+
+#define VIAWD_CONFIG_BASE	0xE8
+
+#define VIAWD_MEM_LEN		8
+
+#define VIAWD_MEM_CTRL		0x00
+#define VIAWD_MEM_CTRL_TRIGGER	0x000000080
+#define VIAWD_MEM_CTRL_DISABLE	0x000000008
+#define VIAWD_MEM_CTRL_POWEROFF	0x000000004
+#define VIAWD_MEM_CTRL_FIRED	0x000000002
+#define VIAWD_MEM_CTRL_ENABLE	0x000000001
+
+#define VIAWD_MEM_COUNT		0x04
+
+#define VIAWD_MEM_COUNT_MIN	1
+#define VIAWD_MEM_COUNT_MAX	1023
+
+#define VIAWD_TIMEOUT_SHUTDOWN	(5 * 60)
+
+#endif