1 /*- 2 * Copyright (c) 2012 Alexander Rybalko <ray@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 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. 13 * 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 24 * SUCH DAMAGE. 25 */ 26 #include <sys/cdefs.h> 27 __FBSDID("$FreeBSD$"); 28 29 #include <sys/param.h> 30 #include <sys/systm.h> 31 #include <sys/watchdog.h> 32 #include <sys/bus.h> 33 #include <sys/kernel.h> 34 #include <sys/module.h> 35 #include <sys/rman.h> 36 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> 41 42 #include <machine/bus.h> 43 #include <machine/cpufunc.h> 44 #include <machine/machdep.h> 45 #include <machine/fdt.h> 46 47 #include <arm/broadcom/bcm2835/bcm2835_wdog.h> 48 49 #define BCM2835_PASWORD 0x5a 50 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 56 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)) 59 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 64 65 #define BCM2835_RSTC_REG 0x00 66 #define BCM2835_RSTS_REG 0x04 67 #define BCM2835_WDOG_REG 0x08 68 69 static struct bcmwd_softc *bcmwd_lsc = NULL; 70 71 struct bcmwd_softc { 72 device_t dev; 73 struct resource * res; 74 bus_space_tag_t bst; 75 bus_space_handle_t bsh; 76 int wdog_armed; 77 int wdog_period; 78 char wdog_passwd; 79 }; 80 81 #ifdef notyet 82 static void bcmwd_watchdog_fn(void *private, u_int cmd, int *error); 83 #endif 84 85 static int 86 bcmwd_probe(device_t dev) 87 { 88 89 if (ofw_bus_is_compatible(dev, "broadcom,bcm2835-wdt")) { 90 device_set_desc(dev, "BCM2708/2835 Watchdog"); 91 return (BUS_PROBE_DEFAULT); 92 } 93 94 return (ENXIO); 95 } 96 97 static int 98 bcmwd_attach(device_t dev) 99 { 100 struct bcmwd_softc *sc; 101 int rid; 102 103 if (bcmwd_lsc != NULL) 104 return (ENXIO); 105 106 sc = device_get_softc(dev); 107 sc->wdog_period = 7; 108 sc->wdog_passwd = BCM2835_PASWORD; 109 sc->wdog_armed = 0; 110 sc->dev = dev; 111 112 rid = 0; 113 sc->res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE); 114 if (sc->res == NULL) { 115 device_printf(dev, "could not allocate memory resource\n"); 116 return (ENXIO); 117 } 118 119 sc->bst = rman_get_bustag(sc->res); 120 sc->bsh = rman_get_bushandle(sc->res); 121 122 bcmwd_lsc = sc; 123 #ifdef notyet 124 EVENTHANDLER_REGISTER(watchdog_list, bcmwd_watchdog_fn, sc, 0); 125 #endif 126 return (0); 127 } 128 129 #ifdef notyet 130 static void 131 bcmwd_watchdog_fn(void *private, u_int cmd, int *error) 132 { 133 /* XXX: not yet */ 134 } 135 #endif 136 137 void 138 bcmwd_watchdog_reset() 139 { 140 141 if (bcmwd_lsc == NULL) 142 return; 143 144 WRITE(bcmwd_lsc, BCM2835_WDOG_REG, 145 (BCM2835_PASWORD << BCM2835_PASSWORD_SHIFT) | 10); 146 147 WRITE(bcmwd_lsc, BCM2835_RSTC_REG, 148 (READ(bcmwd_lsc, BCM2835_RSTC_REG) & BCM2835_RSTC_WRCFG_CLR) | 149 (BCM2835_PASWORD << BCM2835_PASSWORD_SHIFT) | 150 BCM2835_RSTC_WRCFG_FULL_RESET); 151 } 152 153 static device_method_t bcmwd_methods[] = { 154 DEVMETHOD(device_probe, bcmwd_probe), 155 DEVMETHOD(device_attach, bcmwd_attach), 156 157 DEVMETHOD_END 158 }; 159 160 static driver_t bcmwd_driver = { 161 "bcmwd", 162 bcmwd_methods, 163 sizeof(struct bcmwd_softc), 164 }; 165 static devclass_t bcmwd_devclass; 166 167 DRIVER_MODULE(bcmwd, simplebus, bcmwd_driver, bcmwd_devclass, 0, 0); 168