sys/mips/atheros/ar531x/ar5315_wdog.c

   1 /*-
   2  * Copyright (c) 2016, Hiroki Mori
   3  * Copyright (c) 2009, Oleksandr Tymoshenko <gonzo@FreeBSD.org>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice unmodified, this list of conditions, and the following
  11  *    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.
  15  *
  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
  26  * SUCH DAMAGE.
  27  */
  28
  29 /*
  30  * Watchdog driver for AR5315
  31  */
  32
  33 #include <sys/cdefs.h>
  34 __FBSDID("$FreeBSD$");
  35
  36 #include <sys/param.h>
  37 #include <sys/systm.h>
  38 #include <sys/watchdog.h>
  39 #include <sys/bus.h>
  40 #include <sys/kernel.h>
  41 #include <sys/module.h>
  42 #include <sys/sysctl.h>
  43
  44 #include <mips/atheros/ar531x/ar5315reg.h>
  45 #include <mips/atheros/ar531x/ar5315_cpudef.h>
  46
  47 struct ar5315_wdog_softc {
  48         device_t dev;
  49         int armed;
  50         int reboot_from_watchdog;
  51         int debug;
  52 };
  53
  54 static void
  55 ar5315_wdog_watchdog_fn(void *private, u_int cmd, int *error)
  56 {
  57         struct ar5315_wdog_softc *sc = private;
  58         uint64_t timer_val;
  59
  60         cmd &= WD_INTERVAL;
  61         if (sc->debug)
  62                 device_printf(sc->dev, "ar5315_wdog_watchdog_fn: cmd: %x\n", cmd);
  63         if (cmd > 0) {
  64                 timer_val = (uint64_t)(1ULL << cmd) * ar531x_ahb_freq() /
  65                     1000000000;
  66                 if (sc->debug)
  67                         device_printf(sc->dev, "ar5315_wdog_watchdog_fn: programming timer: %jx\n", (uintmax_t) timer_val);
  68                 /*
  69                  * Load timer with large enough value to prevent spurious
  70                  * reset
  71                  */
  72                 ATH_WRITE_REG(ar531x_wdog_timer(),
  73                     ar531x_ahb_freq() * 10);
  74                 ATH_WRITE_REG(ar531x_wdog_ctl(),
  75                     AR5315_WDOG_CTL_RESET);
  76                 ATH_WRITE_REG(ar531x_wdog_timer(),
  77                     (timer_val & 0xffffffff));
  78                 sc->armed = 1;
  79                 *error = 0;
  80         } else {
  81                 if (sc->debug)
  82                         device_printf(sc->dev, "ar5315_wdog_watchdog_fn: disarming\n");
  83                 if (sc->armed) {
  84                         ATH_WRITE_REG(ar531x_wdog_ctl(),
  85                             AR5315_WDOG_CTL_IGNORE);
  86                         sc->armed = 0;
  87                 }
  88         }
  89 }
  90
  91 static int
  92 ar5315_wdog_probe(device_t dev)
  93 {
  94
  95         device_set_desc(dev, "Atheros AR531x watchdog timer");
  96         return (0);
  97 }
  98
  99 static void
 100 ar5315_wdog_sysctl(device_t dev)
 101 {
 102         struct ar5315_wdog_softc *sc = device_get_softc(dev);
 103
 104         struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->dev);
 105         struct sysctl_oid *tree = device_get_sysctl_tree(sc->dev);
 106
 107         SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
 108                 "debug", CTLFLAG_RW, &sc->debug, 0,
 109                 "enable watchdog debugging");
 110         SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
 111                 "armed", CTLFLAG_RD, &sc->armed, 0,
 112                 "whether the watchdog is armed");
 113         SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
 114                 "reboot_from_watchdog", CTLFLAG_RD, &sc->reboot_from_watchdog, 0,
 115                 "whether the system rebooted from the watchdog");
 116 }
 117
 118
 119 static int
 120 ar5315_wdog_attach(device_t dev)
 121 {
 122         struct ar5315_wdog_softc *sc = device_get_softc(dev);
 123
 124         /* Initialise */
 125         sc->reboot_from_watchdog = 0;
 126         sc->armed = 0;
 127         sc->debug = 0;
 128         ATH_WRITE_REG(ar531x_wdog_ctl(), AR5315_WDOG_CTL_IGNORE);
 129
 130         sc->dev = dev;
 131         EVENTHANDLER_REGISTER(watchdog_list, ar5315_wdog_watchdog_fn, sc, 0);
 132         ar5315_wdog_sysctl(dev);
 133
 134         return (0);
 135 }
 136
 137 static device_method_t ar5315_wdog_methods[] = {
 138         DEVMETHOD(device_probe, ar5315_wdog_probe),
 139         DEVMETHOD(device_attach, ar5315_wdog_attach),
 140         DEVMETHOD_END
 141 };
 142
 143 static driver_t ar5315_wdog_driver = {
 144         "ar5315_wdog",
 145         ar5315_wdog_methods,
 146         sizeof(struct ar5315_wdog_softc),
 147 };
 148 static devclass_t ar5315_wdog_devclass;
 149
 150 DRIVER_MODULE(ar5315_wdog, apb, ar5315_wdog_driver, ar5315_wdog_devclass, 0, 0);