Richard W.M. Jones | 9dd986c | 2009-04-25 13:56:19 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Virtual hardware watchdog. |
| 3 | * |
| 4 | * Copyright (C) 2009 Red Hat Inc. |
| 5 | * |
| 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. |
| 10 | * |
| 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. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, |
| 19 | * USA. |
| 20 | * |
| 21 | * By Richard W.M. Jones (rjones@redhat.com). |
| 22 | */ |
| 23 | |
| 24 | #include "qemu-common.h" |
| 25 | #include "qemu-timer.h" |
| 26 | #include "watchdog.h" |
| 27 | #include "hw.h" |
| 28 | #include "isa.h" |
| 29 | #include "pc.h" |
| 30 | |
| 31 | /*#define IB700_DEBUG 1*/ |
| 32 | |
| 33 | #ifdef IB700_DEBUG |
| 34 | #define ib700_debug(fs,...) \ |
| 35 | fprintf(stderr,"ib700: %s: "fs,__func__,##__VA_ARGS__) |
| 36 | #else |
| 37 | #define ib700_debug(fs,...) |
| 38 | #endif |
| 39 | |
| 40 | /* This is the timer. We use a global here because the watchdog |
| 41 | * code ensures there is only one watchdog (it is located at a fixed, |
| 42 | * unchangable IO port, so there could only ever be one anyway). |
| 43 | */ |
| 44 | static QEMUTimer *timer = NULL; |
| 45 | |
| 46 | /* A write to this register enables the timer. */ |
| 47 | static void ib700_write_enable_reg(void *vp, uint32_t addr, uint32_t data) |
| 48 | { |
| 49 | static int time_map[] = { |
| 50 | 30, 28, 26, 24, 22, 20, 18, 16, |
| 51 | 14, 12, 10, 8, 6, 4, 2, 0 |
| 52 | }; |
| 53 | int64 timeout; |
| 54 | |
| 55 | ib700_debug("addr = %x, data = %x\n", addr, data); |
| 56 | |
| 57 | timeout = (int64_t) time_map[data & 0xF] * ticks_per_sec; |
| 58 | qemu_mod_timer(timer, qemu_get_clock (vm_clock) + timeout); |
| 59 | } |
| 60 | |
| 61 | /* A write (of any value) to this register disables the timer. */ |
| 62 | static void ib700_write_disable_reg(void *vp, uint32_t addr, uint32_t data) |
| 63 | { |
| 64 | ib700_debug("addr = %x, data = %x\n", addr, data); |
| 65 | |
| 66 | qemu_del_timer(timer); |
| 67 | } |
| 68 | |
| 69 | /* This is called when the watchdog expires. */ |
| 70 | static void ib700_timer_expired(void *vp) |
| 71 | { |
| 72 | ib700_debug("watchdog expired\n"); |
| 73 | |
| 74 | watchdog_perform_action(); |
| 75 | qemu_del_timer(timer); |
| 76 | } |
| 77 | |
| 78 | static void ib700_save(QEMUFile *f, void *vp) |
| 79 | { |
| 80 | qemu_put_timer(f, timer); |
| 81 | } |
| 82 | |
| 83 | static int ib700_load(QEMUFile *f, void *vp, int version) |
| 84 | { |
| 85 | if (version != 0) |
| 86 | return -EINVAL; |
| 87 | |
| 88 | qemu_get_timer(f, timer); |
| 89 | |
| 90 | return 0; |
| 91 | } |
| 92 | |
| 93 | /* Create and initialize a virtual IB700 during PC creation. */ |
| 94 | static void ib700_pc_init(PCIBus *unused) |
| 95 | { |
| 96 | register_savevm("ib700_wdt", -1, 0, ib700_save, ib700_load, NULL); |
| 97 | |
| 98 | register_ioport_write(0x441, 2, 1, ib700_write_disable_reg, NULL); |
| 99 | register_ioport_write(0x443, 2, 1, ib700_write_enable_reg, NULL); |
| 100 | } |
| 101 | |
| 102 | static WatchdogTimerModel model = { |
| 103 | .wdt_name = "ib700", |
| 104 | .wdt_description = "iBASE 700", |
| 105 | .wdt_pc_init = ib700_pc_init, |
| 106 | }; |
| 107 | |
| 108 | void wdt_ib700_init(void) |
| 109 | { |
| 110 | watchdog_add_model(&model); |
| 111 | timer = qemu_new_timer(vm_clock, ib700_timer_expired, NULL); |
| 112 | } |