1 /* 2 * ASPEED Watchdog Controller 3 * 4 * Copyright (C) 2016-2017 IBM Corp. 5 * 6 * This code is licensed under the GPL version 2 or later. See the 7 * COPYING file in the top-level directory. 8 */ 9 10 #include "qemu/osdep.h" 11 12 #include "qapi/error.h" 13 #include "qemu/log.h" 14 #include "qemu/module.h" 15 #include "qemu/timer.h" 16 #include "sysemu/watchdog.h" 17 #include "hw/misc/aspeed_scu.h" 18 #include "hw/qdev-properties.h" 19 #include "hw/sysbus.h" 20 #include "hw/watchdog/wdt_aspeed.h" 21 #include "migration/vmstate.h" 22 #include "trace.h" 23 24 #define WDT_STATUS (0x00 / 4) 25 #define WDT_RELOAD_VALUE (0x04 / 4) 26 #define WDT_RESTART (0x08 / 4) 27 #define WDT_CTRL (0x0C / 4) 28 #define WDT_CTRL_RESET_MODE_SOC (0x00 << 5) 29 #define WDT_CTRL_RESET_MODE_FULL_CHIP (0x01 << 5) 30 #define WDT_CTRL_1MHZ_CLK BIT(4) 31 #define WDT_CTRL_WDT_EXT BIT(3) 32 #define WDT_CTRL_WDT_INTR BIT(2) 33 #define WDT_CTRL_RESET_SYSTEM BIT(1) 34 #define WDT_CTRL_ENABLE BIT(0) 35 #define WDT_RESET_WIDTH (0x18 / 4) 36 #define WDT_RESET_WIDTH_ACTIVE_HIGH BIT(31) 37 #define WDT_POLARITY_MASK (0xFF << 24) 38 #define WDT_ACTIVE_HIGH_MAGIC (0xA5 << 24) 39 #define WDT_ACTIVE_LOW_MAGIC (0x5A << 24) 40 #define WDT_RESET_WIDTH_PUSH_PULL BIT(30) 41 #define WDT_DRIVE_TYPE_MASK (0xFF << 24) 42 #define WDT_PUSH_PULL_MAGIC (0xA8 << 24) 43 #define WDT_OPEN_DRAIN_MAGIC (0x8A << 24) 44 #define WDT_RESET_MASK1 (0x1c / 4) 45 46 #define WDT_TIMEOUT_STATUS (0x10 / 4) 47 #define WDT_TIMEOUT_CLEAR (0x14 / 4) 48 49 #define WDT_RESTART_MAGIC 0x4755 50 51 #define AST2600_SCU_RESET_CONTROL1 (0x40 / 4) 52 #define SCU_RESET_CONTROL1 (0x04 / 4) 53 #define SCU_RESET_SDRAM BIT(0) 54 55 static bool aspeed_wdt_is_enabled(const AspeedWDTState *s) 56 { 57 return s->regs[WDT_CTRL] & WDT_CTRL_ENABLE; 58 } 59 60 static uint64_t aspeed_wdt_read(void *opaque, hwaddr offset, unsigned size) 61 { 62 AspeedWDTState *s = ASPEED_WDT(opaque); 63 64 trace_aspeed_wdt_read(offset, size); 65 66 offset >>= 2; 67 68 switch (offset) { 69 case WDT_STATUS: 70 return s->regs[WDT_STATUS]; 71 case WDT_RELOAD_VALUE: 72 return s->regs[WDT_RELOAD_VALUE]; 73 case WDT_RESTART: 74 qemu_log_mask(LOG_GUEST_ERROR, 75 "%s: read from write-only reg at offset 0x%" 76 HWADDR_PRIx "\n", __func__, offset); 77 return 0; 78 case WDT_CTRL: 79 return s->regs[WDT_CTRL]; 80 case WDT_RESET_WIDTH: 81 return s->regs[WDT_RESET_WIDTH]; 82 case WDT_RESET_MASK1: 83 return s->regs[WDT_RESET_MASK1]; 84 case WDT_TIMEOUT_STATUS: 85 case WDT_TIMEOUT_CLEAR: 86 qemu_log_mask(LOG_UNIMP, 87 "%s: uninmplemented read at offset 0x%" HWADDR_PRIx "\n", 88 __func__, offset); 89 return 0; 90 default: 91 qemu_log_mask(LOG_GUEST_ERROR, 92 "%s: Out-of-bounds read at offset 0x%" HWADDR_PRIx "\n", 93 __func__, offset); 94 return 0; 95 } 96 97 } 98 99 static void aspeed_wdt_reload(AspeedWDTState *s) 100 { 101 uint64_t reload; 102 103 if (!(s->regs[WDT_CTRL] & WDT_CTRL_1MHZ_CLK)) { 104 reload = muldiv64(s->regs[WDT_RELOAD_VALUE], NANOSECONDS_PER_SECOND, 105 s->pclk_freq); 106 } else { 107 reload = s->regs[WDT_RELOAD_VALUE] * 1000ULL; 108 } 109 110 if (aspeed_wdt_is_enabled(s)) { 111 timer_mod(s->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + reload); 112 } 113 } 114 115 static void aspeed_wdt_reload_1mhz(AspeedWDTState *s) 116 { 117 uint64_t reload = s->regs[WDT_RELOAD_VALUE] * 1000ULL; 118 119 if (aspeed_wdt_is_enabled(s)) { 120 timer_mod(s->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + reload); 121 } 122 } 123 124 static uint64_t aspeed_2400_sanitize_ctrl(uint64_t data) 125 { 126 return data & 0xffff; 127 } 128 129 static uint64_t aspeed_2500_sanitize_ctrl(uint64_t data) 130 { 131 return (data & ~(0xfUL << 8)) | WDT_CTRL_1MHZ_CLK; 132 } 133 134 static uint64_t aspeed_2600_sanitize_ctrl(uint64_t data) 135 { 136 return data & ~(0x7UL << 7); 137 } 138 139 static void aspeed_wdt_write(void *opaque, hwaddr offset, uint64_t data, 140 unsigned size) 141 { 142 AspeedWDTState *s = ASPEED_WDT(opaque); 143 AspeedWDTClass *awc = ASPEED_WDT_GET_CLASS(s); 144 bool enable; 145 146 trace_aspeed_wdt_write(offset, size, data); 147 148 offset >>= 2; 149 150 switch (offset) { 151 case WDT_STATUS: 152 qemu_log_mask(LOG_GUEST_ERROR, 153 "%s: write to read-only reg at offset 0x%" 154 HWADDR_PRIx "\n", __func__, offset); 155 break; 156 case WDT_RELOAD_VALUE: 157 s->regs[WDT_RELOAD_VALUE] = data; 158 break; 159 case WDT_RESTART: 160 if ((data & 0xFFFF) == WDT_RESTART_MAGIC) { 161 s->regs[WDT_STATUS] = s->regs[WDT_RELOAD_VALUE]; 162 awc->wdt_reload(s); 163 } 164 break; 165 case WDT_CTRL: 166 data = awc->sanitize_ctrl(data); 167 enable = data & WDT_CTRL_ENABLE; 168 if (enable && !aspeed_wdt_is_enabled(s)) { 169 s->regs[WDT_CTRL] = data; 170 awc->wdt_reload(s); 171 } else if (!enable && aspeed_wdt_is_enabled(s)) { 172 s->regs[WDT_CTRL] = data; 173 timer_del(s->timer); 174 } else { 175 s->regs[WDT_CTRL] = data; 176 } 177 break; 178 case WDT_RESET_WIDTH: 179 if (awc->reset_pulse) { 180 awc->reset_pulse(s, data & WDT_POLARITY_MASK); 181 } 182 s->regs[WDT_RESET_WIDTH] &= ~awc->ext_pulse_width_mask; 183 s->regs[WDT_RESET_WIDTH] |= data & awc->ext_pulse_width_mask; 184 break; 185 186 case WDT_RESET_MASK1: 187 /* TODO: implement */ 188 s->regs[WDT_RESET_MASK1] = data; 189 break; 190 191 case WDT_TIMEOUT_STATUS: 192 case WDT_TIMEOUT_CLEAR: 193 qemu_log_mask(LOG_UNIMP, 194 "%s: uninmplemented write at offset 0x%" HWADDR_PRIx "\n", 195 __func__, offset); 196 break; 197 default: 198 qemu_log_mask(LOG_GUEST_ERROR, 199 "%s: Out-of-bounds write at offset 0x%" HWADDR_PRIx "\n", 200 __func__, offset); 201 } 202 return; 203 } 204 205 static WatchdogTimerModel model = { 206 .wdt_name = TYPE_ASPEED_WDT, 207 .wdt_description = "Aspeed watchdog device", 208 }; 209 210 static const VMStateDescription vmstate_aspeed_wdt = { 211 .name = "vmstate_aspeed_wdt", 212 .version_id = 0, 213 .minimum_version_id = 0, 214 .fields = (VMStateField[]) { 215 VMSTATE_TIMER_PTR(timer, AspeedWDTState), 216 VMSTATE_UINT32_ARRAY(regs, AspeedWDTState, ASPEED_WDT_REGS_MAX), 217 VMSTATE_END_OF_LIST() 218 } 219 }; 220 221 static const MemoryRegionOps aspeed_wdt_ops = { 222 .read = aspeed_wdt_read, 223 .write = aspeed_wdt_write, 224 .endianness = DEVICE_LITTLE_ENDIAN, 225 .valid.min_access_size = 4, 226 .valid.max_access_size = 4, 227 .valid.unaligned = false, 228 }; 229 230 static void aspeed_wdt_reset(DeviceState *dev) 231 { 232 AspeedWDTState *s = ASPEED_WDT(dev); 233 AspeedWDTClass *awc = ASPEED_WDT_GET_CLASS(s); 234 235 s->regs[WDT_STATUS] = 0x3EF1480; 236 s->regs[WDT_RELOAD_VALUE] = 0x03EF1480; 237 s->regs[WDT_RESTART] = 0; 238 s->regs[WDT_CTRL] = awc->sanitize_ctrl(0); 239 s->regs[WDT_RESET_WIDTH] = 0xFF; 240 241 timer_del(s->timer); 242 } 243 244 static void aspeed_wdt_timer_expired(void *dev) 245 { 246 AspeedWDTState *s = ASPEED_WDT(dev); 247 uint32_t reset_ctrl_reg = ASPEED_WDT_GET_CLASS(s)->reset_ctrl_reg; 248 249 /* Do not reset on SDRAM controller reset */ 250 if (s->scu->regs[reset_ctrl_reg] & SCU_RESET_SDRAM) { 251 timer_del(s->timer); 252 s->regs[WDT_CTRL] = 0; 253 return; 254 } 255 256 qemu_log_mask(CPU_LOG_RESET, "Watchdog timer %" HWADDR_PRIx " expired.\n", 257 s->iomem.addr); 258 watchdog_perform_action(); 259 timer_del(s->timer); 260 } 261 262 #define PCLK_HZ 24000000 263 264 static void aspeed_wdt_realize(DeviceState *dev, Error **errp) 265 { 266 SysBusDevice *sbd = SYS_BUS_DEVICE(dev); 267 AspeedWDTState *s = ASPEED_WDT(dev); 268 269 assert(s->scu); 270 271 s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, aspeed_wdt_timer_expired, dev); 272 273 /* FIXME: This setting should be derived from the SCU hw strapping 274 * register SCU70 275 */ 276 s->pclk_freq = PCLK_HZ; 277 278 memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_wdt_ops, s, 279 TYPE_ASPEED_WDT, ASPEED_WDT_REGS_MAX * 4); 280 sysbus_init_mmio(sbd, &s->iomem); 281 } 282 283 static Property aspeed_wdt_properties[] = { 284 DEFINE_PROP_LINK("scu", AspeedWDTState, scu, TYPE_ASPEED_SCU, 285 AspeedSCUState *), 286 DEFINE_PROP_END_OF_LIST(), 287 }; 288 289 static void aspeed_wdt_class_init(ObjectClass *klass, void *data) 290 { 291 DeviceClass *dc = DEVICE_CLASS(klass); 292 293 dc->desc = "ASPEED Watchdog Controller"; 294 dc->realize = aspeed_wdt_realize; 295 dc->reset = aspeed_wdt_reset; 296 set_bit(DEVICE_CATEGORY_MISC, dc->categories); 297 dc->vmsd = &vmstate_aspeed_wdt; 298 device_class_set_props(dc, aspeed_wdt_properties); 299 } 300 301 static const TypeInfo aspeed_wdt_info = { 302 .parent = TYPE_SYS_BUS_DEVICE, 303 .name = TYPE_ASPEED_WDT, 304 .instance_size = sizeof(AspeedWDTState), 305 .class_init = aspeed_wdt_class_init, 306 .class_size = sizeof(AspeedWDTClass), 307 .abstract = true, 308 }; 309 310 static void aspeed_2400_wdt_class_init(ObjectClass *klass, void *data) 311 { 312 DeviceClass *dc = DEVICE_CLASS(klass); 313 AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass); 314 315 dc->desc = "ASPEED 2400 Watchdog Controller"; 316 awc->offset = 0x20; 317 awc->ext_pulse_width_mask = 0xff; 318 awc->reset_ctrl_reg = SCU_RESET_CONTROL1; 319 awc->wdt_reload = aspeed_wdt_reload; 320 awc->sanitize_ctrl = aspeed_2400_sanitize_ctrl; 321 } 322 323 static const TypeInfo aspeed_2400_wdt_info = { 324 .name = TYPE_ASPEED_2400_WDT, 325 .parent = TYPE_ASPEED_WDT, 326 .instance_size = sizeof(AspeedWDTState), 327 .class_init = aspeed_2400_wdt_class_init, 328 }; 329 330 static void aspeed_2500_wdt_reset_pulse(AspeedWDTState *s, uint32_t property) 331 { 332 if (property) { 333 if (property == WDT_ACTIVE_HIGH_MAGIC) { 334 s->regs[WDT_RESET_WIDTH] |= WDT_RESET_WIDTH_ACTIVE_HIGH; 335 } else if (property == WDT_ACTIVE_LOW_MAGIC) { 336 s->regs[WDT_RESET_WIDTH] &= ~WDT_RESET_WIDTH_ACTIVE_HIGH; 337 } else if (property == WDT_PUSH_PULL_MAGIC) { 338 s->regs[WDT_RESET_WIDTH] |= WDT_RESET_WIDTH_PUSH_PULL; 339 } else if (property == WDT_OPEN_DRAIN_MAGIC) { 340 s->regs[WDT_RESET_WIDTH] &= ~WDT_RESET_WIDTH_PUSH_PULL; 341 } 342 } 343 } 344 345 static void aspeed_2500_wdt_class_init(ObjectClass *klass, void *data) 346 { 347 DeviceClass *dc = DEVICE_CLASS(klass); 348 AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass); 349 350 dc->desc = "ASPEED 2500 Watchdog Controller"; 351 awc->offset = 0x20; 352 awc->ext_pulse_width_mask = 0xfffff; 353 awc->reset_ctrl_reg = SCU_RESET_CONTROL1; 354 awc->reset_pulse = aspeed_2500_wdt_reset_pulse; 355 awc->wdt_reload = aspeed_wdt_reload_1mhz; 356 awc->sanitize_ctrl = aspeed_2500_sanitize_ctrl; 357 } 358 359 static const TypeInfo aspeed_2500_wdt_info = { 360 .name = TYPE_ASPEED_2500_WDT, 361 .parent = TYPE_ASPEED_WDT, 362 .instance_size = sizeof(AspeedWDTState), 363 .class_init = aspeed_2500_wdt_class_init, 364 }; 365 366 static void aspeed_2600_wdt_class_init(ObjectClass *klass, void *data) 367 { 368 DeviceClass *dc = DEVICE_CLASS(klass); 369 AspeedWDTClass *awc = ASPEED_WDT_CLASS(klass); 370 371 dc->desc = "ASPEED 2600 Watchdog Controller"; 372 awc->offset = 0x40; 373 awc->ext_pulse_width_mask = 0xfffff; /* TODO */ 374 awc->reset_ctrl_reg = AST2600_SCU_RESET_CONTROL1; 375 awc->reset_pulse = aspeed_2500_wdt_reset_pulse; 376 awc->wdt_reload = aspeed_wdt_reload_1mhz; 377 awc->sanitize_ctrl = aspeed_2600_sanitize_ctrl; 378 } 379 380 static const TypeInfo aspeed_2600_wdt_info = { 381 .name = TYPE_ASPEED_2600_WDT, 382 .parent = TYPE_ASPEED_WDT, 383 .instance_size = sizeof(AspeedWDTState), 384 .class_init = aspeed_2600_wdt_class_init, 385 }; 386 387 static void wdt_aspeed_register_types(void) 388 { 389 watchdog_add_model(&model); 390 type_register_static(&aspeed_wdt_info); 391 type_register_static(&aspeed_2400_wdt_info); 392 type_register_static(&aspeed_2500_wdt_info); 393 type_register_static(&aspeed_2600_wdt_info); 394 } 395 396 type_init(wdt_aspeed_register_types) 397