hw/watchdog/spapr_watchdog.c

   1 /*
   2  * This library is free software; you can redistribute it and/or
   3  * modify it under the terms of the GNU Lesser General Public
   4  * License as published by the Free Software Foundation; either
   5  * version 2.1 of the License, or (at your option) any later version.
   6  *
   7  * This library is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  10  * Lesser General Public License for more details.
  11  *
  12  * You should have received a copy of the GNU Lesser General Public
  13  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  14  */
  15
  16 #include "qemu/osdep.h"
  17 #include "qapi/error.h"
  18 #include "target/ppc/cpu.h"
  19 #include "migration/vmstate.h"
  20 #include "trace.h"
  21
  22 #include "hw/ppc/spapr.h"
  23
  24 #define FIELD_BE(reg, field, start, len) \
  25     FIELD(reg, field, 64 - (start + len), len)
  26
  27 /*
  28  * Bits 47: "leaveOtherWatchdogsRunningOnTimeout", specified on
  29  * the "Start watchdog" operation,
  30  * 0 - stop out-standing watchdogs on timeout,
  31  * 1 - leave outstanding watchdogs running on timeout
  32  */
  33 FIELD_BE(PSERIES_WDTF, LEAVE_OTHER, 47, 1)
  34
  35 /*    Bits 48-55: "operation" */
  36 FIELD_BE(PSERIES_WDTF, OP, 48, 8)
  37 #define PSERIES_WDTF_OP_START           0x1
  38 #define PSERIES_WDTF_OP_STOP            0x2
  39 #define PSERIES_WDTF_OP_QUERY           0x3
  40 #define PSERIES_WDTF_OP_QUERY_LPM       0x4
  41
  42 /*    Bits 56-63: "timeoutAction" */
  43 FIELD_BE(PSERIES_WDTF, ACTION, 56, 8)
  44 #define PSERIES_WDTF_ACTION_HARD_POWER_OFF  0x1
  45 #define PSERIES_WDTF_ACTION_HARD_RESTART    0x2
  46 #define PSERIES_WDTF_ACTION_DUMP_RESTART    0x3
  47
  48 FIELD_BE(PSERIES_WDTF, RESERVED, 0, 47)
  49
  50 /* Special watchdogNumber for the "stop all watchdogs" operation */
  51 #define PSERIES_WDT_STOP_ALL            ((uint64_t)~0)
  52
  53 /*
  54  * For the "Query watchdog capabilities" operation, a uint64 structure
  55  * defined as:
  56  * Bits 0-15: The minimum supported timeout in milliseconds
  57  * Bits 16-31: The number of watchdogs supported
  58  * Bits 32-63: Reserved
  59  */
  60 FIELD_BE(PSERIES_WDTQ, MIN_TIMEOUT, 0, 16)
  61 FIELD_BE(PSERIES_WDTQ, NUM, 16, 16)
  62
  63 /*
  64  * For the "Query watchdog LPM requirement" operation:
  65  * 1 = The given "watchdogNumber" must be stopped prior to suspending
  66  * 2 = The given "watchdogNumber" does not have to be stopped prior to
  67  * suspending
  68  */
  69 #define PSERIES_WDTQL_STOPPED               1
  70 #define PSERIES_WDTQL_QUERY_NOT_STOPPED     2
  71
  72 #define WDT_MIN_TIMEOUT 1 /* 1ms */
  73
  74 static target_ulong watchdog_stop(unsigned watchdogNumber, SpaprWatchdog *w)
  75 {
  76     target_ulong ret = H_NOOP;
  77
  78     if (timer_pending(&w->timer)) {
  79         timer_del(&w->timer);
  80         ret = H_SUCCESS;
  81     }
  82     trace_spapr_watchdog_stop(watchdogNumber, ret);
  83
  84     return ret;
  85 }
  86
  87 static target_ulong watchdog_stop_all(SpaprMachineState *spapr)
  88 {
  89     target_ulong ret = H_NOOP;
  90     int i;
  91
  92     for (i = 1; i <= ARRAY_SIZE(spapr->wds); ++i) {
  93         target_ulong r = watchdog_stop(i, &spapr->wds[i - 1]);
  94
  95         if (r != H_NOOP && r != H_SUCCESS) {
  96             ret = r;
  97         }
  98     }
  99
 100     return ret;
 101 }
 102
 103 static void watchdog_expired(void *pw)
 104 {
 105     SpaprWatchdog *w = pw;
 106     CPUState *cs;
 107     SpaprMachineState *spapr = SPAPR_MACHINE(qdev_get_machine());
 108     unsigned num = w - spapr->wds;
 109
 110     g_assert(num < ARRAY_SIZE(spapr->wds));
 111     trace_spapr_watchdog_expired(num, w->action);
 112     switch (w->action) {
 113     case PSERIES_WDTF_ACTION_HARD_POWER_OFF:
 114         qemu_system_vmstop_request(RUN_STATE_SHUTDOWN);
 115         break;
 116     case PSERIES_WDTF_ACTION_HARD_RESTART:
 117         qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
 118         break;
 119     case PSERIES_WDTF_ACTION_DUMP_RESTART:
 120         CPU_FOREACH(cs) {
 121             async_run_on_cpu(cs, spapr_do_system_reset_on_cpu, RUN_ON_CPU_NULL);
 122         }
 123         break;
 124     }
 125     if (!w->leave_others) {
 126         watchdog_stop_all(spapr);
 127     }
 128 }
 129
 130 static target_ulong h_watchdog(PowerPCCPU *cpu,
 131                                SpaprMachineState *spapr,
 132                                target_ulong opcode, target_ulong *args)
 133 {
 134     target_ulong ret = H_SUCCESS;
 135     target_ulong flags = args[0];
 136     target_ulong watchdogNumber = args[1]; /* 1-Based per PAPR */
 137     target_ulong timeoutInMs = args[2];
 138     unsigned operation = FIELD_EX64(flags, PSERIES_WDTF, OP);
 139     unsigned timeoutAction = FIELD_EX64(flags, PSERIES_WDTF, ACTION);
 140     SpaprWatchdog *w;
 141
 142     if (FIELD_EX64(flags, PSERIES_WDTF, RESERVED)) {
 143         return H_PARAMETER;
 144     }
 145
 146     switch (operation) {
 147     case PSERIES_WDTF_OP_START:
 148         if (watchdogNumber > ARRAY_SIZE(spapr->wds)) {
 149             return H_P2;
 150         }
 151         if (timeoutInMs <= WDT_MIN_TIMEOUT) {
 152             return H_P3;
 153         }
 154
 155         w = &spapr->wds[watchdogNumber - 1];
 156         switch (timeoutAction) {
 157         case PSERIES_WDTF_ACTION_HARD_POWER_OFF:
 158         case PSERIES_WDTF_ACTION_HARD_RESTART:
 159         case PSERIES_WDTF_ACTION_DUMP_RESTART:
 160             w->action = timeoutAction;
 161             break;
 162         default:
 163             return H_PARAMETER;
 164         }
 165         w->leave_others = FIELD_EX64(flags, PSERIES_WDTF, LEAVE_OTHER);
 166         timer_mod(&w->timer,
 167                   qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + timeoutInMs);
 168         trace_spapr_watchdog_start(flags, watchdogNumber, timeoutInMs);
 169         break;
 170     case PSERIES_WDTF_OP_STOP:
 171         if (watchdogNumber == PSERIES_WDT_STOP_ALL) {
 172             ret = watchdog_stop_all(spapr);
 173         } else if (watchdogNumber <= ARRAY_SIZE(spapr->wds)) {
 174             ret = watchdog_stop(watchdogNumber,
 175                                 &spapr->wds[watchdogNumber - 1]);
 176         } else {
 177             return H_P2;
 178         }
 179         break;
 180     case PSERIES_WDTF_OP_QUERY:
 181         args[0] = FIELD_DP64(0, PSERIES_WDTQ, MIN_TIMEOUT, WDT_MIN_TIMEOUT);
 182         args[0] = FIELD_DP64(args[0], PSERIES_WDTQ, NUM,
 183                              ARRAY_SIZE(spapr->wds));
 184         trace_spapr_watchdog_query(args[0]);
 185         break;
 186     case PSERIES_WDTF_OP_QUERY_LPM:
 187         if (watchdogNumber > ARRAY_SIZE(spapr->wds)) {
 188             return H_P2;
 189         }
 190         args[0] = PSERIES_WDTQL_QUERY_NOT_STOPPED;
 191         trace_spapr_watchdog_query_lpm(args[0]);
 192         break;
 193     default:
 194         return H_PARAMETER;
 195     }
 196
 197     return ret;
 198 }
 199
 200 void spapr_watchdog_init(SpaprMachineState *spapr)
 201 {
 202     int i;
 203
 204     for (i = 0; i < ARRAY_SIZE(spapr->wds); ++i) {
 205         char name[16];
 206         SpaprWatchdog *w = &spapr->wds[i];
 207
 208         snprintf(name, sizeof(name) - 1, "wdt%d", i + 1);
 209         object_initialize_child_with_props(OBJECT(spapr), name, w,
 210                                            sizeof(SpaprWatchdog),
 211                                            TYPE_SPAPR_WDT,
 212                                            &error_fatal, NULL);
 213         qdev_realize(DEVICE(w), NULL, &error_fatal);
 214     }
 215 }
 216
 217 static bool watchdog_needed(void *opaque)
 218 {
 219     SpaprWatchdog *w = opaque;
 220
 221     return timer_pending(&w->timer);
 222 }
 223
 224 static const VMStateDescription vmstate_wdt = {
 225     .name = "spapr_watchdog",
 226     .version_id = 1,
 227     .minimum_version_id = 1,
 228     .needed = watchdog_needed,
 229     .fields = (VMStateField[]) {
 230         VMSTATE_TIMER(timer, SpaprWatchdog),
 231         VMSTATE_UINT8(action, SpaprWatchdog),
 232         VMSTATE_UINT8(leave_others, SpaprWatchdog),
 233         VMSTATE_END_OF_LIST()
 234     }
 235 };
 236
 237 static void spapr_wdt_realize(DeviceState *dev, Error **errp)
 238 {
 239     SpaprWatchdog *w = SPAPR_WDT(dev);
 240     Object *o = OBJECT(dev);
 241
 242     timer_init_ms(&w->timer, QEMU_CLOCK_VIRTUAL, watchdog_expired, w);
 243
 244     object_property_add_uint64_ptr(o, "expire",
 245                                    (uint64_t *)&w->timer.expire_time,
 246                                    OBJ_PROP_FLAG_READ);
 247     object_property_add_uint8_ptr(o, "action", &w->action, OBJ_PROP_FLAG_READ);
 248     object_property_add_uint8_ptr(o, "leaveOtherWatchdogsRunningOnTimeout",
 249                                   &w->leave_others, OBJ_PROP_FLAG_READ);
 250 }
 251
 252 static void spapr_wdt_class_init(ObjectClass *oc, void *data)
 253 {
 254     DeviceClass *dc = DEVICE_CLASS(oc);
 255
 256     dc->realize = spapr_wdt_realize;
 257     dc->vmsd = &vmstate_wdt;
 258     dc->user_creatable = false;
 259 }
 260
 261 static const TypeInfo spapr_wdt_info = {
 262     .name          = TYPE_SPAPR_WDT,
 263     .parent        = TYPE_DEVICE,
 264     .instance_size = sizeof(SpaprWatchdog),
 265     .class_init    = spapr_wdt_class_init,
 266 };
 267
 268 static void spapr_watchdog_register_types(void)
 269 {
 270     spapr_register_hypercall(H_WATCHDOG, h_watchdog);
 271     type_register_static(&spapr_wdt_info);
 272 }
 273
 274 type_init(spapr_watchdog_register_types)