sys/arch/mips/adm5120/dev/admwdog.c

   1 /* $NetBSD: admwdog.c,v 1.1 2007/03/20 08:52:02 dyoung Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2007 David Young.  All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or
   7  * without modification, are permitted provided that the following
   8  * conditions are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above
  12  *    copyright notice, this list of conditions and the following
  13  *    disclaimer in the documentation and/or other materials provided
  14  *    with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY
  17  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  18  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
  19  * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR
  20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
  21  * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  22  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
  23  * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
  25  * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  26  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
  27  * OF SUCH DAMAGE.
  28  */
  29
  30 #include <sys/cdefs.h>
  31
  32 __KERNEL_RCSID(0, "$NetBSD: admwdog.c,v 1.1 2007/03/20 08:52:02 dyoung Exp $");
  33
  34 #include <sys/param.h>
  35 #include <sys/systm.h>
  36 #include <sys/device.h>
  37 #include <sys/wdog.h>
  38 #include <sys/kernel.h> /* for hz */
  39
  40 #include <machine/bus.h>
  41
  42 #include <dev/sysmon/sysmonvar.h>
  43
  44 #include <mips/adm5120/include/adm5120reg.h>
  45 #include <mips/adm5120/include/adm5120var.h>
  46 #include <mips/adm5120/include/adm5120_obiovar.h>
  47 #include <mips/adm5120/dev/if_admswvar.h>
  48
  49 /* maximum watchdog period, seconds */
  50 #define ADMWDOG_MAX_PERIOD      (__SHIFTOUT_MASK(ADM5120_WDOG_WTS_MASK) / 100)
  51
  52 static int admwdog_setmode(struct sysmon_wdog *smw);
  53 static int admwdog_tickle(struct sysmon_wdog *smw);
  54
  55 static inline uint32_t
  56 admwdog_read(struct admsw_softc *sc)
  57 {
  58         return bus_space_read_4(sc->sc_st, sc->sc_ioh, ADM5120_WDOG0);
  59 }
  60
  61 static inline void
  62 admwdog_write(struct admsw_softc *sc, uint32_t val)
  63 {
  64         bus_space_write_4(sc->sc_st, sc->sc_ioh, ADM5120_WDOG0, val);
  65 }
  66
  67 static void
  68 admwdog_reset(struct admsw_softc *sc)
  69 {
  70         int s;
  71         uint32_t wdog0;
  72
  73         wdog0 = __SHIFTIN(sc->sc_smw.smw_period * 100, ADM5120_WDOG_WTS_MASK) |
  74             __SHIFTIN(1, ADM5120_WDOG_WT_MASK);
  75
  76         s = splhigh();
  77
  78         admwdog_write(sc, wdog0);
  79         (void)admwdog_read(sc);
  80         admwdog_write(sc, ADM5120_WDOG0_WTTR | wdog0);
  81
  82         splx(s);
  83 }
  84
  85 static int
  86 admwdog_setmode(struct sysmon_wdog *smw)
  87 {
  88         struct admsw_softc *sc = smw->smw_cookie;
  89
  90         if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
  91                 admwdog_write(sc, 0);
  92                 return 0;
  93         }
  94
  95         if (smw->smw_period == WDOG_PERIOD_DEFAULT)
  96                 smw->smw_period = 32;
  97         else if (smw->smw_period > ADMWDOG_MAX_PERIOD)
  98                 return EINVAL;
  99
 100         admwdog_reset(sc);
 101
 102         return 0;
 103 }
 104
 105 static int
 106 admwdog_tickle(struct sysmon_wdog *smw)
 107 {
 108         struct admsw_softc *sc = smw->smw_cookie;
 109
 110         (void)admwdog_read(sc);
 111         return 0;
 112 }
 113
 114 void
 115 admwdog_attach(struct admsw_softc *sc)
 116 {
 117         struct sysmon_wdog *smw = &sc->sc_smw;
 118
 119         /* deactivate watchdog */
 120         admwdog_write(sc, 0);
 121
 122         smw->smw_name = device_xname(&sc->sc_dev);
 123         smw->smw_cookie = sc;
 124         smw->smw_setmode = admwdog_setmode;
 125         smw->smw_tickle = admwdog_tickle;
 126         smw->smw_period = ADMWDOG_MAX_PERIOD;
 127
 128         sysmon_wdog_register(&sc->sc_smw);
 129 }