2 * Virtual hardware watchdog.
4 * Copyright (C) 2009 Red Hat Inc.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version 2
9 * of the License, or (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, see <http://www.gnu.org/licenses/>.
19 * By Richard W.M. Jones (rjones@redhat.com).
22 #include "qemu-common.h"
23 #include "qemu-timer.h"
29 /*#define IB700_DEBUG 1*/
32 #define ib700_debug(fs,...) \
33 fprintf(stderr,"ib700: %s: "fs,__func__,##__VA_ARGS__)
35 #define ib700_debug(fs,...)
38 typedef struct IB700state
{
43 /* This is the timer. We use a global here because the watchdog
44 * code ensures there is only one watchdog (it is located at a fixed,
45 * unchangable IO port, so there could only ever be one anyway).
48 /* A write to this register enables the timer. */
49 static void ib700_write_enable_reg(void *vp
, uint32_t addr
, uint32_t data
)
52 static int time_map
[] = {
53 30, 28, 26, 24, 22, 20, 18, 16,
54 14, 12, 10, 8, 6, 4, 2, 0
58 ib700_debug("addr = %x, data = %x\n", addr
, data
);
60 timeout
= (int64_t) time_map
[data
& 0xF] * get_ticks_per_sec();
61 qemu_mod_timer(s
->timer
, qemu_get_clock (vm_clock
) + timeout
);
64 /* A write (of any value) to this register disables the timer. */
65 static void ib700_write_disable_reg(void *vp
, uint32_t addr
, uint32_t data
)
69 ib700_debug("addr = %x, data = %x\n", addr
, data
);
71 qemu_del_timer(s
->timer
);
74 /* This is called when the watchdog expires. */
75 static void ib700_timer_expired(void *vp
)
79 ib700_debug("watchdog expired\n");
81 watchdog_perform_action();
82 qemu_del_timer(s
->timer
);
85 static const VMStateDescription vmstate_ib700
= {
88 .minimum_version_id
= 0,
89 .minimum_version_id_old
= 0,
90 .fields
= (VMStateField
[]) {
91 VMSTATE_TIMER(timer
, IB700State
),
96 static int wdt_ib700_init(ISADevice
*dev
)
98 IB700State
*s
= DO_UPCAST(IB700State
, dev
, dev
);
100 s
->timer
= qemu_new_timer(vm_clock
, ib700_timer_expired
, s
);
101 vmstate_register(-1, &vmstate_ib700
, s
);
102 register_ioport_write(0x441, 2, 1, ib700_write_disable_reg
, s
);
103 register_ioport_write(0x443, 2, 1, ib700_write_enable_reg
, s
);
108 static WatchdogTimerModel model
= {
110 .wdt_description
= "iBASE 700",
113 static ISADeviceInfo wdt_ib700_info
= {
114 .qdev
.name
= "ib700",
115 .qdev
.size
= sizeof(IB700State
),
116 .init
= wdt_ib700_init
,
119 static void wdt_ib700_register_devices(void)
121 watchdog_add_model(&model
);
122 isa_qdev_register(&wdt_ib700_info
);
125 device_init(wdt_ib700_register_devices
);