sys/mips/atheros/ar71xx_wdog.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2009, Oleksandr Tymoshenko <gonzo@FreeBSD.org>
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice unmodified, this list of conditions, and the following
  12  *    disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 /*
  31  * Watchdog driver for AR71xx
  32  */
  33
  34 #include <sys/cdefs.h>
  35 __FBSDID("$FreeBSD$");
  36
  37 #include <sys/param.h>
  38 #include <sys/systm.h>
  39 #include <sys/watchdog.h>
  40 #include <sys/bus.h>
  41 #include <sys/kernel.h>
  42 #include <sys/module.h>
  43 #include <sys/sysctl.h>
  44
  45 #include <mips/atheros/ar71xxreg.h>
  46 #include <mips/atheros/ar71xx_cpudef.h>
  47
  48 struct ar71xx_wdog_softc {
  49         device_t dev;
  50         int armed;
  51         int reboot_from_watchdog;
  52         int debug;
  53 };
  54
  55 static void
  56 ar71xx_wdog_watchdog_fn(void *private, u_int cmd, int *error)
  57 {
  58         struct ar71xx_wdog_softc *sc = private;
  59         uint64_t timer_val;
  60
  61         cmd &= WD_INTERVAL;
  62         if (sc->debug)
  63                 device_printf(sc->dev, "ar71xx_wdog_watchdog_fn: cmd: %x\n", cmd);
  64         if (cmd > 0) {
  65                 timer_val = (uint64_t)(1ULL << cmd) * ar71xx_ahb_freq() /
  66                     1000000000;
  67                 if (sc->debug)
  68                         device_printf(sc->dev, "ar71xx_wdog_watchdog_fn: programming timer: %jx\n", (uintmax_t) timer_val);
  69                 /*
  70                  * Load timer with large enough value to prevent spurious
  71                  * reset
  72                  */
  73                 ATH_WRITE_REG(AR71XX_RST_WDOG_TIMER,
  74                     ar71xx_ahb_freq() * 10);
  75                 ATH_WRITE_REG(AR71XX_RST_WDOG_CONTROL,
  76                     RST_WDOG_ACTION_RESET);
  77                 ATH_WRITE_REG(AR71XX_RST_WDOG_TIMER,
  78                     (timer_val & 0xffffffff));
  79                 sc->armed = 1;
  80                 *error = 0;
  81         } else {
  82                 if (sc->debug)
  83                         device_printf(sc->dev, "ar71xx_wdog_watchdog_fn: disarming\n");
  84                 if (sc->armed) {
  85                         ATH_WRITE_REG(AR71XX_RST_WDOG_CONTROL,
  86                             RST_WDOG_ACTION_NOACTION);
  87                         sc->armed = 0;
  88                 }
  89         }
  90 }
  91
  92 static int
  93 ar71xx_wdog_probe(device_t dev)
  94 {
  95
  96         device_set_desc(dev, "Atheros AR71XX watchdog timer");
  97         return (BUS_PROBE_NOWILDCARD);
  98 }
  99
 100 static void
 101 ar71xx_wdog_sysctl(device_t dev)
 102 {
 103         struct ar71xx_wdog_softc *sc = device_get_softc(dev);
 104
 105         struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->dev);
 106         struct sysctl_oid *tree = device_get_sysctl_tree(sc->dev);
 107
 108         SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
 109                 "debug", CTLFLAG_RW, &sc->debug, 0,
 110                 "enable watchdog debugging");
 111         SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
 112                 "armed", CTLFLAG_RD, &sc->armed, 0,
 113                 "whether the watchdog is armed");
 114         SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
 115                 "reboot_from_watchdog", CTLFLAG_RD, &sc->reboot_from_watchdog, 0,
 116                 "whether the system rebooted from the watchdog");
 117 }
 118
 119
 120 static int
 121 ar71xx_wdog_attach(device_t dev)
 122 {
 123         struct ar71xx_wdog_softc *sc = device_get_softc(dev);
 124
 125         /* Initialise */
 126         sc->reboot_from_watchdog = 0;
 127         sc->armed = 0;
 128         sc->debug = 0;
 129
 130         if (ATH_READ_REG(AR71XX_RST_WDOG_CONTROL) & RST_WDOG_LAST) {
 131                 device_printf (dev,
 132                     "Previous reset was due to watchdog timeout\n");
 133                 sc->reboot_from_watchdog = 1;
 134         }
 135
 136         ATH_WRITE_REG(AR71XX_RST_WDOG_CONTROL, RST_WDOG_ACTION_NOACTION);
 137
 138         sc->dev = dev;
 139         EVENTHANDLER_REGISTER(watchdog_list, ar71xx_wdog_watchdog_fn, sc, 0);
 140         ar71xx_wdog_sysctl(dev);
 141
 142         return (0);
 143 }
 144
 145 static device_method_t ar71xx_wdog_methods[] = {
 146         DEVMETHOD(device_probe, ar71xx_wdog_probe),
 147         DEVMETHOD(device_attach, ar71xx_wdog_attach),
 148         {0, 0},
 149 };
 150
 151 static driver_t ar71xx_wdog_driver = {
 152         "ar71xx_wdog",
 153         ar71xx_wdog_methods,
 154         sizeof(struct ar71xx_wdog_softc),
 155 };
 156 static devclass_t ar71xx_wdog_devclass;
 157
 158 DRIVER_MODULE(ar71xx_wdog, nexus, ar71xx_wdog_driver, ar71xx_wdog_devclass, 0, 0);