blob: eea8da60596cbac218b9647f2c4e46b8ce0ad47f [file] [log] [blame]
/*
* Virtual hardware watchdog.
*
* Copyright (C) 2009 Red Hat Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*
* By Richard W.M. Jones (rjones@redhat.com).
*/
#include "qemu/osdep.h"
#include "qemu/module.h"
#include "qemu/timer.h"
#include "sysemu/watchdog.h"
#include "hw/isa/isa.h"
#include "migration/vmstate.h"
#include "qom/object.h"
/*#define IB700_DEBUG 1*/
#ifdef IB700_DEBUG
#define ib700_debug(fs,...) \
fprintf(stderr,"ib700: %s: "fs,__func__,##__VA_ARGS__)
#else
#define ib700_debug(fs,...)
#endif
#define TYPE_IB700 "ib700"
typedef struct IB700state IB700State;
DECLARE_INSTANCE_CHECKER(IB700State, IB700,
TYPE_IB700)
struct IB700state {
ISADevice parent_obj;
QEMUTimer *timer;
PortioList port_list;
};
/* This is the timer. We use a global here because the watchdog
* code ensures there is only one watchdog (it is located at a fixed,
* unchangeable IO port, so there could only ever be one anyway).
*/
/* A write to this register enables the timer. */
static void ib700_write_enable_reg(void *vp, uint32_t addr, uint32_t data)
{
IB700State *s = vp;
static int time_map[] = {
30, 28, 26, 24, 22, 20, 18, 16,
14, 12, 10, 8, 6, 4, 2, 0
};
int64_t timeout;
ib700_debug("addr = %x, data = %x\n", addr, data);
timeout = (int64_t) time_map[data & 0xF] * NANOSECONDS_PER_SECOND;
timer_mod(s->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + timeout);
}
/* A write (of any value) to this register disables the timer. */
static void ib700_write_disable_reg(void *vp, uint32_t addr, uint32_t data)
{
IB700State *s = vp;
ib700_debug("addr = %x, data = %x\n", addr, data);
timer_del(s->timer);
}
/* This is called when the watchdog expires. */
static void ib700_timer_expired(void *vp)
{
IB700State *s = vp;
ib700_debug("watchdog expired\n");
watchdog_perform_action();
timer_del(s->timer);
}
static const VMStateDescription vmstate_ib700 = {
.name = "ib700_wdt",
.version_id = 0,
.minimum_version_id = 0,
.fields = (const VMStateField[]) {
VMSTATE_TIMER_PTR(timer, IB700State),
VMSTATE_END_OF_LIST()
}
};
static const MemoryRegionPortio wdt_portio_list[] = {
{ 0x441, 2, 1, .write = ib700_write_disable_reg, },
{ 0x443, 2, 1, .write = ib700_write_enable_reg, },
PORTIO_END_OF_LIST(),
};
static void wdt_ib700_realize(DeviceState *dev, Error **errp)
{
IB700State *s = IB700(dev);
ib700_debug("watchdog init\n");
s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, ib700_timer_expired, s);
portio_list_init(&s->port_list, OBJECT(s), wdt_portio_list, s, "ib700");
portio_list_add(&s->port_list, isa_address_space_io(&s->parent_obj), 0);
}
static void wdt_ib700_reset(DeviceState *dev)
{
IB700State *s = IB700(dev);
ib700_debug("watchdog reset\n");
timer_del(s->timer);
}
static void wdt_ib700_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = wdt_ib700_realize;
dc->reset = wdt_ib700_reset;
dc->vmsd = &vmstate_ib700;
set_bit(DEVICE_CATEGORY_WATCHDOG, dc->categories);
dc->desc = "iBASE 700";
}
static const TypeInfo wdt_ib700_info = {
.name = TYPE_IB700,
.parent = TYPE_ISA_DEVICE,
.instance_size = sizeof(IB700State),
.class_init = wdt_ib700_class_init,
};
static void wdt_ib700_register_types(void)
{
type_register_static(&wdt_ib700_info);
}
type_init(wdt_ib700_register_types)