qemu/hw/watchdog/wdt_diag288.c

   1 /*
   2  * watchdog device diag288 support
   3  *
   4  * Copyright IBM, Corp. 2015
   5  *
   6  * Authors:
   7  *  Xu Wang <gesaint@linux.vnet.ibm.com>
   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 const VMStateDescription vmstate_diag288 = {
  25     .name = "vmstate_diag288",
  26     .version_id = 0,
  27     .minimum_version_id = 0,
  28     .fields = (VMStateField[]) {
  29         VMSTATE_TIMER_PTR(timer, DIAG288State),
  30         VMSTATE_BOOL(enabled, DIAG288State),
  31         VMSTATE_END_OF_LIST()
  32     }
  33 };
  34
  35 static void wdt_diag288_reset(DeviceState *dev)
  36 {
  37     DIAG288State *diag288 = DIAG288(dev);
  38
  39     diag288->enabled = false;
  40     timer_del(diag288->timer);
  41 }
  42
  43 static void diag288_reset(void *opaque)
  44 {
  45     DeviceState *diag288 = opaque;
  46
  47     wdt_diag288_reset(diag288);
  48 }
  49
  50 static void diag288_timer_expired(void *dev)
  51 {
  52     qemu_log_mask(CPU_LOG_RESET, "Watchdog timer expired.\n");
  53     watchdog_perform_action();
  54     wdt_diag288_reset(dev);
  55 }
  56
  57 static int wdt_diag288_handle_timer(DIAG288State *diag288,
  58                                      uint64_t func, uint64_t timeout)
  59 {
  60     switch (func) {
  61     case WDT_DIAG288_INIT:
  62         diag288->enabled = true;
  63         /* fall through */
  64     case WDT_DIAG288_CHANGE:
  65         if (!diag288->enabled) {
  66             return -1;
  67         }
  68         timer_mod(diag288->timer,
  69                   qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
  70                   timeout * get_ticks_per_sec());
  71         break;
  72     case WDT_DIAG288_CANCEL:
  73         if (!diag288->enabled) {
  74             return -1;
  75         }
  76         diag288->enabled = false;
  77         timer_del(diag288->timer);
  78         break;
  79     default:
  80         return -1;
  81     }
  82
  83     return 0;
  84 }
  85
  86 static void wdt_diag288_realize(DeviceState *dev, Error **errp)
  87 {
  88     DIAG288State *diag288 = DIAG288(dev);
  89
  90     qemu_register_reset(diag288_reset, diag288);
  91     diag288->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, diag288_timer_expired,
  92                                   dev);
  93 }
  94
  95 static void wdt_diag288_unrealize(DeviceState *dev, Error **errp)
  96 {
  97     DIAG288State *diag288 = DIAG288(dev);
  98
  99     timer_del(diag288->timer);
 100     timer_free(diag288->timer);
 101 }
 102
 103 static void wdt_diag288_class_init(ObjectClass *klass, void *data)
 104 {
 105     DeviceClass *dc = DEVICE_CLASS(klass);
 106     DIAG288Class *diag288 = DIAG288_CLASS(klass);
 107
 108     dc->realize = wdt_diag288_realize;
 109     dc->unrealize = wdt_diag288_unrealize;
 110     dc->reset = wdt_diag288_reset;
 111     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 112     dc->vmsd = &vmstate_diag288;
 113     diag288->handle_timer = wdt_diag288_handle_timer;
 114 }
 115
 116 static const TypeInfo wdt_diag288_info = {
 117     .class_init = wdt_diag288_class_init,
 118     .parent = TYPE_DEVICE,
 119     .name  = TYPE_WDT_DIAG288,
 120     .instance_size  = sizeof(DIAG288State),
 121     .class_size = sizeof(DIAG288Class),
 122 };
 123
 124 static void wdt_diag288_register_types(void)
 125 {
 126     watchdog_add_model(&model);
 127     type_register_static(&wdt_diag288_info);
 128 }
 129
 130 type_init(wdt_diag288_register_types)