/* $NetBSD: admwdog.c,v 1.4 2012/10/27 17:18:01 chs Exp $ */

/*-
 * Copyright (c) 2007 David Young.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or
 * without modification, are permitted provided that the following
 * conditions are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above
 *    copyright notice, this list of conditions and the following
 *    disclaimer in the documentation and/or other materials provided
 *    with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>

__KERNEL_RCSID(0, "$NetBSD: admwdog.c,v 1.4 2012/10/27 17:18:01 chs Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/wdog.h>
#include <sys/kernel.h> /* for hz */

#include <sys/bus.h>

#include <dev/sysmon/sysmonvar.h>

#include <mips/adm5120/include/adm5120reg.h>
#include <mips/adm5120/include/adm5120var.h>
#include <mips/adm5120/include/adm5120_obiovar.h>
#include <mips/adm5120/dev/if_admswvar.h>

/* maximum watchdog period, seconds */
#define ADMWDOG_MAX_PERIOD      (__SHIFTOUT_MASK(ADM5120_WDOG_WTS_MASK) / 100)

static int admwdog_setmode(struct sysmon_wdog *smw);
static int admwdog_tickle(struct sysmon_wdog *smw);

static inline uint32_t
admwdog_read(struct admsw_softc *sc)
{
        return bus_space_read_4(sc->sc_st, sc->sc_ioh, ADM5120_WDOG0);
}

static inline void
admwdog_write(struct admsw_softc *sc, uint32_t val)
{
        bus_space_write_4(sc->sc_st, sc->sc_ioh, ADM5120_WDOG0, val);
}

static void
admwdog_reset(struct admsw_softc *sc)
{
        int s;
        uint32_t wdog0;

        wdog0 = __SHIFTIN(sc->sc_smw.smw_period * 100, ADM5120_WDOG_WTS_MASK) |
            __SHIFTIN(1, ADM5120_WDOG_WT_MASK);

        s = splhigh();

        admwdog_write(sc, wdog0);
        (void)admwdog_read(sc);
        admwdog_write(sc, ADM5120_WDOG0_WTTR | wdog0);

        splx(s);
}

static int
admwdog_setmode(struct sysmon_wdog *smw)
{
        struct admsw_softc *sc = smw->smw_cookie;

        if ((smw->smw_mode & WDOG_MODE_MASK) == WDOG_MODE_DISARMED) {
                admwdog_write(sc, 0);
                return 0;
        }

        if (smw->smw_period == WDOG_PERIOD_DEFAULT)
                smw->smw_period = 32;
        else if (smw->smw_period > ADMWDOG_MAX_PERIOD)
                return EINVAL;

        admwdog_reset(sc);

        return 0;
}

static int
admwdog_tickle(struct sysmon_wdog *smw)
{
        struct admsw_softc *sc = smw->smw_cookie;

        (void)admwdog_read(sc);
        return 0;
}

void
admwdog_attach(struct admsw_softc *sc)
{
        struct sysmon_wdog *smw = &sc->sc_smw;

        /* deactivate watchdog */
        admwdog_write(sc, 0);

        smw->smw_name = device_xname(sc->sc_dev);
        smw->smw_cookie = sc;
        smw->smw_setmode = admwdog_setmode;
        smw->smw_tickle = admwdog_tickle;
        smw->smw_period = ADMWDOG_MAX_PERIOD;

        sysmon_wdog_register(&sc->sc_smw);
}