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-rw-r--r--hw/watchdog/wdt_ib700.c160
1 files changed, 160 insertions, 0 deletions
diff --git a/hw/watchdog/wdt_ib700.c b/hw/watchdog/wdt_ib700.c
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index 000000000..91d1bdc0d
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+++ b/hw/watchdog/wdt_ib700.c
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+/*
+ * 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 = (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 WatchdogTimerModel model = {
+ .wdt_name = "ib700",
+ .wdt_description = "iBASE 700",
+};
+
+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)
+{
+ watchdog_add_model(&model);
+ type_register_static(&wdt_ib700_info);
+}
+
+type_init(wdt_ib700_register_types)