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 "qemu/osdep.h" |
15 | #include "sysemu/reset.h" |
16 | #include "sysemu/watchdog.h" |
17 | #include "hw/sysbus.h" |
18 | #include "qemu/timer.h" |
19 | #include "hw/watchdog/wdt_diag288.h" |
20 | #include "migration/vmstate.h" |
21 | #include "qemu/log.h" |
22 | #include "qemu/module.h" |
23 | |
24 | static WatchdogTimerModel model = { |
25 | .wdt_name = TYPE_WDT_DIAG288, |
26 | .wdt_description = "diag288 device for s390x platform" , |
27 | }; |
28 | |
29 | static const VMStateDescription vmstate_diag288 = { |
30 | .name = "vmstate_diag288" , |
31 | .version_id = 0, |
32 | .minimum_version_id = 0, |
33 | .fields = (VMStateField[]) { |
34 | VMSTATE_TIMER_PTR(timer, DIAG288State), |
35 | VMSTATE_BOOL(enabled, DIAG288State), |
36 | VMSTATE_END_OF_LIST() |
37 | } |
38 | }; |
39 | |
40 | static void wdt_diag288_reset(DeviceState *dev) |
41 | { |
42 | DIAG288State *diag288 = DIAG288(dev); |
43 | |
44 | diag288->enabled = false; |
45 | timer_del(diag288->timer); |
46 | } |
47 | |
48 | static void diag288_reset(void *opaque) |
49 | { |
50 | DeviceState *diag288 = opaque; |
51 | |
52 | wdt_diag288_reset(diag288); |
53 | } |
54 | |
55 | static void diag288_timer_expired(void *dev) |
56 | { |
57 | qemu_log_mask(CPU_LOG_RESET, "Watchdog timer expired.\n" ); |
58 | /* Reset the watchdog only if the guest gets notified about |
59 | * expiry. watchdog_perform_action() may temporarily relinquish |
60 | * the BQL; reset before triggering the action to avoid races with |
61 | * diag288 instructions. */ |
62 | switch (get_watchdog_action()) { |
63 | case WATCHDOG_ACTION_DEBUG: |
64 | case WATCHDOG_ACTION_NONE: |
65 | case WATCHDOG_ACTION_PAUSE: |
66 | break; |
67 | default: |
68 | wdt_diag288_reset(dev); |
69 | } |
70 | watchdog_perform_action(); |
71 | } |
72 | |
73 | static int wdt_diag288_handle_timer(DIAG288State *diag288, |
74 | uint64_t func, uint64_t timeout) |
75 | { |
76 | switch (func) { |
77 | case WDT_DIAG288_INIT: |
78 | diag288->enabled = true; |
79 | /* fall through */ |
80 | case WDT_DIAG288_CHANGE: |
81 | if (!diag288->enabled) { |
82 | return -1; |
83 | } |
84 | timer_mod(diag288->timer, |
85 | qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + |
86 | timeout * NANOSECONDS_PER_SECOND); |
87 | break; |
88 | case WDT_DIAG288_CANCEL: |
89 | if (!diag288->enabled) { |
90 | return -1; |
91 | } |
92 | diag288->enabled = false; |
93 | timer_del(diag288->timer); |
94 | break; |
95 | default: |
96 | return -1; |
97 | } |
98 | |
99 | return 0; |
100 | } |
101 | |
102 | static void wdt_diag288_realize(DeviceState *dev, Error **errp) |
103 | { |
104 | DIAG288State *diag288 = DIAG288(dev); |
105 | |
106 | qemu_register_reset(diag288_reset, diag288); |
107 | diag288->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, diag288_timer_expired, |
108 | dev); |
109 | } |
110 | |
111 | static void wdt_diag288_unrealize(DeviceState *dev, Error **errp) |
112 | { |
113 | DIAG288State *diag288 = DIAG288(dev); |
114 | |
115 | timer_del(diag288->timer); |
116 | timer_free(diag288->timer); |
117 | } |
118 | |
119 | static void wdt_diag288_class_init(ObjectClass *klass, void *data) |
120 | { |
121 | DeviceClass *dc = DEVICE_CLASS(klass); |
122 | DIAG288Class *diag288 = DIAG288_CLASS(klass); |
123 | |
124 | dc->realize = wdt_diag288_realize; |
125 | dc->unrealize = wdt_diag288_unrealize; |
126 | dc->reset = wdt_diag288_reset; |
127 | dc->hotpluggable = false; |
128 | set_bit(DEVICE_CATEGORY_MISC, dc->categories); |
129 | dc->vmsd = &vmstate_diag288; |
130 | diag288->handle_timer = wdt_diag288_handle_timer; |
131 | } |
132 | |
133 | static const TypeInfo wdt_diag288_info = { |
134 | .class_init = wdt_diag288_class_init, |
135 | .parent = TYPE_DEVICE, |
136 | .name = TYPE_WDT_DIAG288, |
137 | .instance_size = sizeof(DIAG288State), |
138 | .class_size = sizeof(DIAG288Class), |
139 | }; |
140 | |
141 | static void wdt_diag288_register_types(void) |
142 | { |
143 | watchdog_add_model(&model); |
144 | type_register_static(&wdt_diag288_info); |
145 | } |
146 | |
147 | type_init(wdt_diag288_register_types) |
148 | |