2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2011 Fabien Thomas <fabient@FreeBSD.org>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
32 #include <sys/param.h>
33 #include <sys/eventhandler.h>
34 #include <sys/kernel.h>
35 #include <sys/module.h>
36 #include <sys/systm.h>
38 #include <machine/bus.h>
40 #include <machine/resource.h>
41 #include <sys/watchdog.h>
43 #include <isa/isavar.h>
44 #include <dev/pci/pcivar.h>
48 #define viawd_read_4(sc, off) bus_read_4((sc)->wd_res, (off))
49 #define viawd_write_4(sc, off, val) \
50 bus_write_4((sc)->wd_res, (off), (val))
52 static struct viawd_device viawd_devices[] = {
53 { DEVICEID_VT8251, "VIA VT8251 watchdog timer" },
54 { DEVICEID_CX700, "VIA CX700 watchdog timer" },
55 { DEVICEID_VX800, "VIA VX800 watchdog timer" },
56 { DEVICEID_VX855, "VIA VX855 watchdog timer" },
57 { DEVICEID_VX900, "VIA VX900 watchdog timer" },
61 static devclass_t viawd_devclass;
64 viawd_tmr_state(struct viawd_softc *sc, int enable)
68 reg = viawd_read_4(sc, VIAWD_MEM_CTRL);
70 reg |= VIAWD_MEM_CTRL_TRIGGER | VIAWD_MEM_CTRL_ENABLE;
72 reg &= ~VIAWD_MEM_CTRL_ENABLE;
73 viawd_write_4(sc, VIAWD_MEM_CTRL, reg);
77 viawd_tmr_set(struct viawd_softc *sc, unsigned int timeout)
80 /* Keep value in range. */
81 if (timeout < VIAWD_MEM_COUNT_MIN)
82 timeout = VIAWD_MEM_COUNT_MIN;
83 else if (timeout > VIAWD_MEM_COUNT_MAX)
84 timeout = VIAWD_MEM_COUNT_MAX;
86 viawd_write_4(sc, VIAWD_MEM_COUNT, timeout);
87 sc->timeout = timeout;
91 * Watchdog event handler - called by the framework to enable or disable
92 * the watchdog or change the initial timeout value.
95 viawd_event(void *arg, unsigned int cmd, int *error)
97 struct viawd_softc *sc = arg;
100 /* Convert from power-of-two-ns to second. */
102 timeout = ((uint64_t)1 << cmd) / 1000000000;
104 if (timeout != sc->timeout)
105 viawd_tmr_set(sc, timeout);
106 viawd_tmr_state(sc, 1);
109 viawd_tmr_state(sc, 0);
112 /* Look for a supported VIA south bridge. */
113 static struct viawd_device *
114 viawd_find(device_t dev)
116 struct viawd_device *id;
118 if (pci_get_vendor(dev) != VENDORID_VIA)
120 for (id = viawd_devices; id->desc != NULL; id++)
121 if (pci_get_device(dev) == id->device)
127 viawd_identify(driver_t *driver, device_t parent)
130 if (viawd_find(parent) == NULL)
133 if (device_find_child(parent, driver->name, -1) == NULL)
134 BUS_ADD_CHILD(parent, 0, driver->name, 0);
138 viawd_probe(device_t dev)
140 struct viawd_device *id;
142 id = viawd_find(device_get_parent(dev));
143 KASSERT(id != NULL, ("parent should be a valid VIA SB"));
144 device_set_desc(dev, id->desc);
145 return (BUS_PROBE_GENERIC);
149 viawd_attach(device_t dev)
152 struct viawd_softc *sc;
153 uint32_t pmbase, reg;
155 sc = device_get_softc(dev);
158 sb_dev = device_get_parent(dev);
159 if (sb_dev == NULL) {
160 device_printf(dev, "Can not find watchdog device.\n");
165 /* Get watchdog memory base. */
166 pmbase = pci_read_config(sb_dev, VIAWD_CONFIG_BASE, 4);
169 "Watchdog disabled in BIOS or hardware\n");
173 /* Allocate I/O register space. */
174 sc->wd_rid = VIAWD_CONFIG_BASE;
175 sc->wd_res = bus_alloc_resource_any(sb_dev, SYS_RES_MEMORY, &sc->wd_rid,
176 RF_ACTIVE | RF_SHAREABLE);
177 if (sc->wd_res == NULL) {
178 device_printf(dev, "Unable to map watchdog memory\n");
181 if (rman_get_size(sc->wd_res) < VIAWD_MEM_LEN) {
182 device_printf(dev, "Bad size for watchdog memory: %#x\n",
183 (unsigned)rman_get_size(sc->wd_res));
187 /* Check if watchdog fired last boot. */
188 reg = viawd_read_4(sc, VIAWD_MEM_CTRL);
189 if (reg & VIAWD_MEM_CTRL_FIRED) {
191 "ERROR: watchdog rebooted the system\n");
192 /* Reset bit state. */
193 viawd_write_4(sc, VIAWD_MEM_CTRL, reg);
196 /* Register the watchdog event handler. */
197 sc->ev_tag = EVENTHANDLER_REGISTER(watchdog_list, viawd_event, sc, 0);
201 if (sc->wd_res != NULL)
202 bus_release_resource(sb_dev, SYS_RES_MEMORY,
203 sc->wd_rid, sc->wd_res);
208 viawd_detach(device_t dev)
210 struct viawd_softc *sc;
213 sc = device_get_softc(dev);
215 /* Deregister event handler. */
216 if (sc->ev_tag != NULL)
217 EVENTHANDLER_DEREGISTER(watchdog_list, sc->ev_tag);
221 * Do not stop the watchdog on shutdown if active but bump the
222 * timer to avoid spurious reset.
224 reg = viawd_read_4(sc, VIAWD_MEM_CTRL);
225 if (reg & VIAWD_MEM_CTRL_ENABLE) {
226 viawd_tmr_set(sc, VIAWD_TIMEOUT_SHUTDOWN);
227 viawd_tmr_state(sc, 1);
229 "Keeping watchog alive during shutdown for %d seconds\n",
230 VIAWD_TIMEOUT_SHUTDOWN);
233 if (sc->wd_res != NULL)
234 bus_release_resource(sc->sb_dev, SYS_RES_MEMORY,
235 sc->wd_rid, sc->wd_res);
240 static device_method_t viawd_methods[] = {
241 DEVMETHOD(device_identify, viawd_identify),
242 DEVMETHOD(device_probe, viawd_probe),
243 DEVMETHOD(device_attach, viawd_attach),
244 DEVMETHOD(device_detach, viawd_detach),
245 DEVMETHOD(device_shutdown, viawd_detach),
249 static driver_t viawd_driver = {
252 sizeof(struct viawd_softc),
255 DRIVER_MODULE(viawd, isab, viawd_driver, viawd_devclass, NULL, NULL);