hw/watchdog/wdt_diag288.c

   1 /*
   2  * watchdog device diag288 support
   3  *
   4  * Copyright IBM, Corp. 2015
   5  *
   6  * Authors:
   7  *  Xu Wang <[email protected]>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2 or (at your
  10  * option) any later version.  See the COPYING file in the top-level directory.
  11  *
  12  */
  13
  14 #include "sysemu/watchdog.h"
  15 #include "hw/sysbus.h"
  16 #include "qemu/timer.h"
  17 #include "hw/watchdog/wdt_diag288.h"
  18
  19 static WatchdogTimerModel model = {
  20     .wdt_name = TYPE_WDT_DIAG288,
  21     .wdt_description = "diag288 device for s390x platform",
  22 };
  23
  24 static void wdt_diag288_reset(DeviceState *dev)
  25 {
  26     DIAG288State *diag288 = DIAG288(dev);
  27
  28     diag288->enabled = false;
  29     timer_del(diag288->timer);
  30 }
  31
  32 static void diag288_timer_expired(void *dev)
  33 {
  34     qemu_log_mask(CPU_LOG_RESET, "Watchdog timer expired.\n");
  35     watchdog_perform_action();
  36     wdt_diag288_reset(dev);
  37 }
  38
  39 static int wdt_diag288_handle_timer(DIAG288State *diag288,
  40                                      uint64_t func, uint64_t timeout)
  41 {
  42     switch (func) {
  43     case WDT_DIAG288_INIT:
  44         diag288->enabled = true;
  45         /* fall through */
  46     case WDT_DIAG288_CHANGE:
  47         if (!diag288->enabled) {
  48             return -1;
  49         }
  50         timer_mod(diag288->timer,
  51                   qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
  52                   timeout * get_ticks_per_sec());
  53         break;
  54     case WDT_DIAG288_CANCEL:
  55         if (!diag288->enabled) {
  56             return -1;
  57         }
  58         diag288->enabled = false;
  59         timer_del(diag288->timer);
  60         break;
  61     default:
  62         return -1;
  63     }
  64
  65     return 0;
  66 }
  67
  68 static void wdt_diag288_realize(DeviceState *dev, Error **errp)
  69 {
  70     DIAG288State *diag288 = DIAG288(dev);
  71
  72     diag288->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, diag288_timer_expired,
  73                                   dev);
  74 }
  75
  76 static void wdt_diag288_unrealize(DeviceState *dev, Error **errp)
  77 {
  78     DIAG288State *diag288 = DIAG288(dev);
  79
  80     timer_del(diag288->timer);
  81     timer_free(diag288->timer);
  82 }
  83
  84 static void wdt_diag288_class_init(ObjectClass *klass, void *data)
  85 {
  86     DeviceClass *dc = DEVICE_CLASS(klass);
  87     DIAG288Class *diag288 = DIAG288_CLASS(klass);
  88
  89     dc->realize = wdt_diag288_realize;
  90     dc->unrealize = wdt_diag288_unrealize;
  91     dc->reset = wdt_diag288_reset;
  92     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
  93     diag288->handle_timer = wdt_diag288_handle_timer;
  94 }
  95
  96 static const TypeInfo wdt_diag288_info = {
  97     .class_init = wdt_diag288_class_init,
  98     .parent = TYPE_DEVICE,
  99     .name  = TYPE_WDT_DIAG288,
 100     .instance_size  = sizeof(DIAG288State),
 101     .class_size = sizeof(DIAG288Class),
 102 };
 103
 104 static void wdt_diag288_register_types(void)
 105 {
 106     watchdog_add_model(&model);
 107     type_register_static(&wdt_diag288_info);
 108 }
 109
 110 type_init(wdt_diag288_register_types)