/*
 * Copyright (c) 2015 The DragonFly Project.  All rights reserved.
 *
 * This code is derived from software contributed to The DragonFly Project
 * by Imre Vadász <imre@vdsz.com>
 *
 * 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.
 * 3. Neither the name of The DragonFly Project nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific, prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``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
 * COPYRIGHT HOLDERS OR CONTRIBUTORS 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 "opt_acpi.h"
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/bus.h>
#include <sys/rman.h>
#include <dev/acpica/acpi_pvpanic/panic_notifier.h>

#include "acpi.h"

#include <dev/acpica/acpivar.h>

#define PVPANIC_GUESTPANIC      (1 << 0)

ACPI_MODULE_NAME("pvpanic")

struct acpi_pvpanic_softc {
        device_t                dev;
        ACPI_HANDLE             handle;
        int                     pvpanic_port_rid;
        struct resource         *pvpanic_port_res;
        bus_space_tag_t         pvpanic_iot;
        bus_space_handle_t      pvpanic_ioh;
        struct panicerinfo      pvpanic_info;
};

static int      acpi_pvpanic_probe(device_t dev);
static int      acpi_pvpanic_attach(device_t dev);
static int      acpi_pvpanic_detach(device_t dev);
static void     acpi_pvpanic_panic(void *arg);

static device_method_t acpi_pvpanic_methods[] = {
        DEVMETHOD(device_probe,         acpi_pvpanic_probe),
        DEVMETHOD(device_attach,        acpi_pvpanic_attach),
        DEVMETHOD(device_detach,        acpi_pvpanic_detach),

        DEVMETHOD_END
};

static driver_t acpi_pvpanic_driver = {
        "acpi_pvpanic",
        acpi_pvpanic_methods,
        sizeof(struct acpi_pvpanic_softc),
};

static devclass_t acpi_pvpanic_devclass;
DRIVER_MODULE(acpi_pvpanic, acpi, acpi_pvpanic_driver, acpi_pvpanic_devclass,
    NULL, NULL);
MODULE_DEPEND(acpi_pvpanic, acpi, 1, 1, 1);
MODULE_VERSION(acpi_pvpanic, 1);

static int
acpi_pvpanic_probe(device_t dev)
{
        static char *pvpanic_ids[] = { "QEMU0001", NULL };

        if (acpi_disabled("pvpanic") ||
            ACPI_ID_PROBE(device_get_parent(dev), dev, pvpanic_ids) == NULL ||
            device_get_unit(dev) != 0)
                return (ENXIO);

        device_set_desc(dev, "Qemu pvpanic device");
        return (0);
}

static int
acpi_pvpanic_attach(device_t dev)
{
        struct  acpi_pvpanic_softc *sc;
        uint8_t val;

        sc = device_get_softc(dev);
        sc->dev = dev;
        sc->handle = acpi_get_handle(dev);

        sc->pvpanic_port_rid = 0;
        sc->pvpanic_port_res = bus_alloc_resource_any(sc->dev, SYS_RES_IOPORT,
            &sc->pvpanic_port_rid, RF_ACTIVE);
        if (sc->pvpanic_port_res == NULL) {
                device_printf(dev, "can't allocate pvpanic port\n");
                return ENXIO;
        }
        sc->pvpanic_iot = rman_get_bustag(sc->pvpanic_port_res);
        sc->pvpanic_ioh = rman_get_bushandle(sc->pvpanic_port_res);

        /* Check for guest panic notification support */
        val = bus_space_read_1(sc->pvpanic_iot, sc->pvpanic_ioh, 0);
        if (!(val & PVPANIC_GUESTPANIC)) {
                device_printf(dev, "No PVPANIC_GUESTPANIC support\n");
                goto fail;
        }

        device_printf(dev, "Registering panic callback\n");
        sc->pvpanic_info.notifier = acpi_pvpanic_panic;
        sc->pvpanic_info.arg = sc;
        if (set_panic_notifier(&sc->pvpanic_info) != 0) {
                device_printf(dev, "Failed to register panic notifier\n");
                goto fail;
        }
        return (0);

fail:
        bus_release_resource(dev, SYS_RES_IOPORT,
            sc->pvpanic_port_rid, sc->pvpanic_port_res);
        return ENXIO;
}

static int
acpi_pvpanic_detach(device_t dev)
{
        struct  acpi_pvpanic_softc *sc = device_get_softc(dev);

        set_panic_notifier(NULL);

        bus_release_resource(dev, SYS_RES_IOPORT,
            sc->pvpanic_port_rid, sc->pvpanic_port_res);

        return (0);
}

static void
acpi_pvpanic_panic(void *arg)
{
        struct acpi_pvpanic_softc *sc = (struct acpi_pvpanic_softc *)arg;

        bus_space_write_1(sc->pvpanic_iot, sc->pvpanic_ioh, 0,
            PVPANIC_GUESTPANIC);
}