2 * Copyright (c) 2012 Alexander Rybalko <ray@freebsd.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/watchdog.h>
33 #include <sys/kernel.h>
34 #include <sys/module.h>
37 #include <dev/fdt/fdt_common.h>
38 #include <dev/ofw/openfirm.h>
39 #include <dev/ofw/ofw_bus.h>
40 #include <dev/ofw/ofw_bus_subr.h>
42 #include <machine/bus.h>
43 #include <machine/cpufunc.h>
44 #include <machine/machdep.h>
45 #include <machine/fdt.h>
47 #include <arm/broadcom/bcm2835/bcm2835_wdog.h>
49 #define BCM2835_PASWORD 0x5a
51 #define BCM2835_WDOG_RESET 0
52 #define BCM2835_PASSWORD_MASK 0xff000000
53 #define BCM2835_PASSWORD_SHIFT 24
54 #define BCM2835_WDOG_TIME_MASK 0x000fffff
55 #define BCM2835_WDOG_TIME_SHIFT 0
57 #define READ(_sc, _r) bus_space_read_4((_sc)->bst, (_sc)->bsh, (_r))
58 #define WRITE(_sc, _r, _v) bus_space_write_4((_sc)->bst, (_sc)->bsh, (_r), (_v))
60 #define BCM2835_RSTC_WRCFG_CLR 0xffffffcf
61 #define BCM2835_RSTC_WRCFG_SET 0x00000030
62 #define BCM2835_RSTC_WRCFG_FULL_RESET 0x00000020
63 #define BCM2835_RSTC_RESET 0x00000102
65 #define BCM2835_RSTC_REG 0x00
66 #define BCM2835_RSTS_REG 0x04
67 #define BCM2835_WDOG_REG 0x08
69 static struct bcmwd_softc *bcmwd_lsc = NULL;
73 struct resource * res;
75 bus_space_handle_t bsh;
82 static void bcmwd_watchdog_fn(void *private, u_int cmd, int *error);
85 bcmwd_probe(device_t dev)
88 if (!ofw_bus_status_okay(dev))
91 if (ofw_bus_is_compatible(dev, "broadcom,bcm2835-wdt")) {
92 device_set_desc(dev, "BCM2708/2835 Watchdog");
93 return (BUS_PROBE_DEFAULT);
100 bcmwd_attach(device_t dev)
102 struct bcmwd_softc *sc;
105 if (bcmwd_lsc != NULL)
108 sc = device_get_softc(dev);
110 sc->wdog_passwd = BCM2835_PASWORD;
115 sc->res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
116 if (sc->res == NULL) {
117 device_printf(dev, "could not allocate memory resource\n");
121 sc->bst = rman_get_bustag(sc->res);
122 sc->bsh = rman_get_bushandle(sc->res);
125 mtx_init(&sc->mtx, "BCM2835 Watchdog", "bcmwd", MTX_DEF);
126 EVENTHANDLER_REGISTER(watchdog_list, bcmwd_watchdog_fn, sc, 0);
132 bcmwd_watchdog_fn(void *private, u_int cmd, int *error)
134 struct bcmwd_softc *sc;
144 sec = ((uint64_t)1 << (cmd & WD_INTERVAL)) / 1000000000;
145 if (sec == 0 || sec > 15) {
148 * disable watchdog as watchdog(9) requires
150 device_printf(sc->dev,
151 "Can't arm, timeout must be between 1-15 seconds\n");
152 WRITE(sc, BCM2835_RSTC_REG,
153 (BCM2835_PASWORD << BCM2835_PASSWORD_SHIFT) |
155 mtx_unlock(&sc->mtx);
159 ticks = (sec << 16) & BCM2835_WDOG_TIME_MASK;
160 reg = (BCM2835_PASWORD << BCM2835_PASSWORD_SHIFT) | ticks;
161 WRITE(sc, BCM2835_WDOG_REG, reg);
163 reg = READ(sc, BCM2835_RSTC_REG);
164 reg &= BCM2835_RSTC_WRCFG_CLR;
165 reg |= BCM2835_RSTC_WRCFG_FULL_RESET;
166 reg |= (BCM2835_PASWORD << BCM2835_PASSWORD_SHIFT);
167 WRITE(sc, BCM2835_RSTC_REG, reg);
172 WRITE(sc, BCM2835_RSTC_REG,
173 (BCM2835_PASWORD << BCM2835_PASSWORD_SHIFT) |
176 mtx_unlock(&sc->mtx);
180 bcmwd_watchdog_reset()
183 if (bcmwd_lsc == NULL)
186 WRITE(bcmwd_lsc, BCM2835_WDOG_REG,
187 (BCM2835_PASWORD << BCM2835_PASSWORD_SHIFT) | 10);
189 WRITE(bcmwd_lsc, BCM2835_RSTC_REG,
190 (READ(bcmwd_lsc, BCM2835_RSTC_REG) & BCM2835_RSTC_WRCFG_CLR) |
191 (BCM2835_PASWORD << BCM2835_PASSWORD_SHIFT) |
192 BCM2835_RSTC_WRCFG_FULL_RESET);
195 static device_method_t bcmwd_methods[] = {
196 DEVMETHOD(device_probe, bcmwd_probe),
197 DEVMETHOD(device_attach, bcmwd_attach),
202 static driver_t bcmwd_driver = {
205 sizeof(struct bcmwd_softc),
207 static devclass_t bcmwd_devclass;
209 DRIVER_MODULE(bcmwd, simplebus, bcmwd_driver, bcmwd_devclass, 0, 0);