qemu/hw/watchdog/wdt_diag288.c

145 lines
3.7 KiB
C

/*
* watchdog device diag288 support
*
* Copyright IBM, Corp. 2015
*
* Authors:
* Xu Wang <gesaint@linux.vnet.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or (at your
* option) any later version. See the COPYING file in the top-level directory.
*
*/
#include "qemu/osdep.h"
#include "sysemu/watchdog.h"
#include "hw/sysbus.h"
#include "qemu/timer.h"
#include "hw/watchdog/wdt_diag288.h"
#include "qemu/log.h"
static WatchdogTimerModel model = {
.wdt_name = TYPE_WDT_DIAG288,
.wdt_description = "diag288 device for s390x platform",
};
static const VMStateDescription vmstate_diag288 = {
.name = "vmstate_diag288",
.version_id = 0,
.minimum_version_id = 0,
.fields = (VMStateField[]) {
VMSTATE_TIMER_PTR(timer, DIAG288State),
VMSTATE_BOOL(enabled, DIAG288State),
VMSTATE_END_OF_LIST()
}
};
static void wdt_diag288_reset(DeviceState *dev)
{
DIAG288State *diag288 = DIAG288(dev);
diag288->enabled = false;
timer_del(diag288->timer);
}
static void diag288_reset(void *opaque)
{
DeviceState *diag288 = opaque;
wdt_diag288_reset(diag288);
}
static void diag288_timer_expired(void *dev)
{
qemu_log_mask(CPU_LOG_RESET, "Watchdog timer expired.\n");
/* Reset the watchdog only if the guest gets notified about
* expiry. watchdog_perform_action() may temporarily relinquish
* the BQL; reset before triggering the action to avoid races with
* diag288 instructions. */
switch (get_watchdog_action()) {
case WATCHDOG_ACTION_DEBUG:
case WATCHDOG_ACTION_NONE:
case WATCHDOG_ACTION_PAUSE:
break;
default:
wdt_diag288_reset(dev);
}
watchdog_perform_action();
}
static int wdt_diag288_handle_timer(DIAG288State *diag288,
uint64_t func, uint64_t timeout)
{
switch (func) {
case WDT_DIAG288_INIT:
diag288->enabled = true;
/* fall through */
case WDT_DIAG288_CHANGE:
if (!diag288->enabled) {
return -1;
}
timer_mod(diag288->timer,
qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
timeout * NANOSECONDS_PER_SECOND);
break;
case WDT_DIAG288_CANCEL:
if (!diag288->enabled) {
return -1;
}
diag288->enabled = false;
timer_del(diag288->timer);
break;
default:
return -1;
}
return 0;
}
static void wdt_diag288_realize(DeviceState *dev, Error **errp)
{
DIAG288State *diag288 = DIAG288(dev);
qemu_register_reset(diag288_reset, diag288);
diag288->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, diag288_timer_expired,
dev);
}
static void wdt_diag288_unrealize(DeviceState *dev, Error **errp)
{
DIAG288State *diag288 = DIAG288(dev);
timer_del(diag288->timer);
timer_free(diag288->timer);
}
static void wdt_diag288_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
DIAG288Class *diag288 = DIAG288_CLASS(klass);
dc->realize = wdt_diag288_realize;
dc->unrealize = wdt_diag288_unrealize;
dc->reset = wdt_diag288_reset;
dc->hotpluggable = false;
set_bit(DEVICE_CATEGORY_MISC, dc->categories);
dc->vmsd = &vmstate_diag288;
diag288->handle_timer = wdt_diag288_handle_timer;
}
static const TypeInfo wdt_diag288_info = {
.class_init = wdt_diag288_class_init,
.parent = TYPE_DEVICE,
.name = TYPE_WDT_DIAG288,
.instance_size = sizeof(DIAG288State),
.class_size = sizeof(DIAG288Class),
};
static void wdt_diag288_register_types(void)
{
watchdog_add_model(&model);
type_register_static(&wdt_diag288_info);
}
type_init(wdt_diag288_register_types)