sys/mips/atheros/ar71xx_wdog.c

   1 /*-
   2  * Copyright (c) 2009, Oleksandr Tymoshenko <gonzo@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 unmodified, this list of conditions, and the following
  10  *    disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  */
  27
  28 /*
  29  * Watchdog driver for AR71xx
  30  */
  31
  32 #include <sys/cdefs.h>
  33 __FBSDID("$FreeBSD$");
  34
  35 #include <sys/param.h>
  36 #include <sys/systm.h>
  37 #include <sys/watchdog.h>
  38 #include <sys/bus.h>
  39 #include <sys/kernel.h>
  40 #include <sys/module.h>
  41 #include <sys/sysctl.h>
  42
  43 #include <mips/atheros/ar71xxreg.h>
  44 #include <mips/atheros/ar71xx_cpudef.h>
  45
  46 struct ar71xx_wdog_softc {
  47         device_t dev;
  48         int armed;
  49         int reboot_from_watchdog;
  50         int debug;
  51 };
  52
  53 static void
  54 ar71xx_wdog_watchdog_fn(void *private, u_int cmd, int *error)
  55 {
  56         struct ar71xx_wdog_softc *sc = private;
  57         uint64_t timer_val;
  58
  59         cmd &= WD_INTERVAL;
  60         if (sc->debug)
  61                 device_printf(sc->dev, "ar71xx_wdog_watchdog_fn: cmd: %x\n", cmd);
  62         if (cmd > 0) {
  63                 timer_val = (uint64_t)(1ULL << cmd) * ar71xx_ahb_freq() /
  64                     1000000000;
  65                 if (sc->debug)
  66                         device_printf(sc->dev, "ar71xx_wdog_watchdog_fn: programming timer: %jx\n", (uintmax_t) timer_val);
  67                 /*
  68                  * Load timer with large enough value to prevent spurious
  69                  * reset
  70                  */
  71                 ATH_WRITE_REG(AR71XX_RST_WDOG_TIMER,
  72                     ar71xx_ahb_freq() * 10);
  73                 ATH_WRITE_REG(AR71XX_RST_WDOG_CONTROL,
  74                     RST_WDOG_ACTION_RESET);
  75                 ATH_WRITE_REG(AR71XX_RST_WDOG_TIMER,
  76                     (timer_val & 0xffffffff));
  77                 sc->armed = 1;
  78                 *error = 0;
  79         } else {
  80                 if (sc->debug)
  81                         device_printf(sc->dev, "ar71xx_wdog_watchdog_fn: disarming\n");
  82                 if (sc->armed) {
  83                         ATH_WRITE_REG(AR71XX_RST_WDOG_CONTROL,
  84                             RST_WDOG_ACTION_NOACTION);
  85                         sc->armed = 0;
  86                 }
  87         }
  88 }
  89
  90 static int
  91 ar71xx_wdog_probe(device_t dev)
  92 {
  93
  94         device_set_desc(dev, "Atheros AR71XX watchdog timer");
  95         return (0);
  96 }
  97
  98 static void
  99 ar71xx_wdog_sysctl(device_t dev)
 100 {
 101         struct ar71xx_wdog_softc *sc = device_get_softc(dev);
 102
 103         struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->dev);
 104         struct sysctl_oid *tree = device_get_sysctl_tree(sc->dev);
 105
 106         SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
 107                 "debug", CTLFLAG_RW, &sc->debug, 0,
 108                 "enable watchdog debugging");
 109         SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
 110                 "armed", CTLFLAG_RD, &sc->armed, 0,
 111                 "whether the watchdog is armed");
 112         SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
 113                 "reboot_from_watchdog", CTLFLAG_RD, &sc->reboot_from_watchdog, 0,
 114                 "whether the system rebooted from the watchdog");
 115 }
 116
 117
 118 static int
 119 ar71xx_wdog_attach(device_t dev)
 120 {
 121         struct ar71xx_wdog_softc *sc = device_get_softc(dev);
 122
 123         /* Initialise */
 124         sc->reboot_from_watchdog = 0;
 125         sc->armed = 0;
 126         sc->debug = 0;
 127
 128         if (ATH_READ_REG(AR71XX_RST_WDOG_CONTROL) & RST_WDOG_LAST) {
 129                 device_printf (dev,
 130                     "Previous reset was due to watchdog timeout\n");
 131                 sc->reboot_from_watchdog = 1;
 132         }
 133
 134         ATH_WRITE_REG(AR71XX_RST_WDOG_CONTROL, RST_WDOG_ACTION_NOACTION);
 135
 136         sc->dev = dev;
 137         EVENTHANDLER_REGISTER(watchdog_list, ar71xx_wdog_watchdog_fn, sc, 0);
 138         ar71xx_wdog_sysctl(dev);
 139
 140         return (0);
 141 }
 142
 143 static device_method_t ar71xx_wdog_methods[] = {
 144         DEVMETHOD(device_probe, ar71xx_wdog_probe),
 145         DEVMETHOD(device_attach, ar71xx_wdog_attach),
 146         {0, 0},
 147 };
 148
 149 static driver_t ar71xx_wdog_driver = {
 150         "ar71xx_wdog",
 151         ar71xx_wdog_methods,
 152         sizeof(struct ar71xx_wdog_softc),
 153 };
 154 static devclass_t ar71xx_wdog_devclass;
 155
 156 DRIVER_MODULE(ar71xx_wdog, nexus, ar71xx_wdog_driver, ar71xx_wdog_devclass, 0, 0);