cadence_ttc.c (12323B)
1 /* 2 * Xilinx Zynq cadence TTC model 3 * 4 * Copyright (c) 2011 Xilinx Inc. 5 * Copyright (c) 2012 Peter A.G. Crosthwaite (peter.crosthwaite@petalogix.com) 6 * Copyright (c) 2012 PetaLogix Pty Ltd. 7 * Written By Haibing Ma 8 * M. Habib 9 * 10 * This program is free software; you can redistribute it and/or 11 * modify it under the terms of the GNU General Public License 12 * as published by the Free Software Foundation; either version 13 * 2 of the License, or (at your option) any later version. 14 * 15 * You should have received a copy of the GNU General Public License along 16 * with this program; if not, see <http://www.gnu.org/licenses/>. 17 */ 18 19 #include "qemu/osdep.h" 20 #include "hw/irq.h" 21 #include "hw/sysbus.h" 22 #include "migration/vmstate.h" 23 #include "qemu/module.h" 24 #include "qemu/timer.h" 25 #include "qom/object.h" 26 27 #include "hw/timer/cadence_ttc.h" 28 29 #ifdef CADENCE_TTC_ERR_DEBUG 30 #define DB_PRINT(...) do { \ 31 fprintf(stderr, ": %s: ", __func__); \ 32 fprintf(stderr, ## __VA_ARGS__); \ 33 } while (0) 34 #else 35 #define DB_PRINT(...) 36 #endif 37 38 #define COUNTER_INTR_IV 0x00000001 39 #define COUNTER_INTR_M1 0x00000002 40 #define COUNTER_INTR_M2 0x00000004 41 #define COUNTER_INTR_M3 0x00000008 42 #define COUNTER_INTR_OV 0x00000010 43 #define COUNTER_INTR_EV 0x00000020 44 45 #define COUNTER_CTRL_DIS 0x00000001 46 #define COUNTER_CTRL_INT 0x00000002 47 #define COUNTER_CTRL_DEC 0x00000004 48 #define COUNTER_CTRL_MATCH 0x00000008 49 #define COUNTER_CTRL_RST 0x00000010 50 51 #define CLOCK_CTRL_PS_EN 0x00000001 52 #define CLOCK_CTRL_PS_V 0x0000001e 53 54 static void cadence_timer_update(CadenceTimerState *s) 55 { 56 qemu_set_irq(s->irq, !!(s->reg_intr & s->reg_intr_en)); 57 } 58 59 static CadenceTimerState *cadence_timer_from_addr(void *opaque, 60 hwaddr offset) 61 { 62 unsigned int index; 63 CadenceTTCState *s = (CadenceTTCState *)opaque; 64 65 index = (offset >> 2) % 3; 66 67 return &s->timer[index]; 68 } 69 70 static uint64_t cadence_timer_get_ns(CadenceTimerState *s, uint64_t timer_steps) 71 { 72 /* timer_steps has max value of 0x100000000. double check it 73 * (or overflow can happen below) */ 74 assert(timer_steps <= 1ULL << 32); 75 76 uint64_t r = timer_steps * 1000000000ULL; 77 if (s->reg_clock & CLOCK_CTRL_PS_EN) { 78 r >>= 16 - (((s->reg_clock & CLOCK_CTRL_PS_V) >> 1) + 1); 79 } else { 80 r >>= 16; 81 } 82 r /= (uint64_t)s->freq; 83 return r; 84 } 85 86 static uint64_t cadence_timer_get_steps(CadenceTimerState *s, uint64_t ns) 87 { 88 uint64_t to_divide = 1000000000ULL; 89 90 uint64_t r = ns; 91 /* for very large intervals (> 8s) do some division first to stop 92 * overflow (costs some prescision) */ 93 while (r >= 8ULL << 30 && to_divide > 1) { 94 r /= 1000; 95 to_divide /= 1000; 96 } 97 r <<= 16; 98 /* keep early-dividing as needed */ 99 while (r >= 8ULL << 30 && to_divide > 1) { 100 r /= 1000; 101 to_divide /= 1000; 102 } 103 r *= (uint64_t)s->freq; 104 if (s->reg_clock & CLOCK_CTRL_PS_EN) { 105 r /= 1 << (((s->reg_clock & CLOCK_CTRL_PS_V) >> 1) + 1); 106 } 107 108 r /= to_divide; 109 return r; 110 } 111 112 /* determine if x is in between a and b, exclusive of a, inclusive of b */ 113 114 static inline int64_t is_between(int64_t x, int64_t a, int64_t b) 115 { 116 if (a < b) { 117 return x > a && x <= b; 118 } 119 return x < a && x >= b; 120 } 121 122 static void cadence_timer_run(CadenceTimerState *s) 123 { 124 int i; 125 int64_t event_interval, next_value; 126 127 assert(s->cpu_time_valid); /* cadence_timer_sync must be called first */ 128 129 if (s->reg_count & COUNTER_CTRL_DIS) { 130 s->cpu_time_valid = 0; 131 return; 132 } 133 134 { /* figure out what's going to happen next (rollover or match) */ 135 int64_t interval = (uint64_t)((s->reg_count & COUNTER_CTRL_INT) ? 136 (int64_t)s->reg_interval + 1 : 0x10000ULL) << 16; 137 next_value = (s->reg_count & COUNTER_CTRL_DEC) ? -1ULL : interval; 138 for (i = 0; i < 3; ++i) { 139 int64_t cand = (uint64_t)s->reg_match[i] << 16; 140 if (is_between(cand, (uint64_t)s->reg_value, next_value)) { 141 next_value = cand; 142 } 143 } 144 } 145 DB_PRINT("next timer event value: %09llx\n", 146 (unsigned long long)next_value); 147 148 event_interval = next_value - (int64_t)s->reg_value; 149 event_interval = (event_interval < 0) ? -event_interval : event_interval; 150 151 timer_mod(s->timer, s->cpu_time + 152 cadence_timer_get_ns(s, event_interval)); 153 } 154 155 static void cadence_timer_sync(CadenceTimerState *s) 156 { 157 int i; 158 int64_t r, x; 159 int64_t interval = ((s->reg_count & COUNTER_CTRL_INT) ? 160 (int64_t)s->reg_interval + 1 : 0x10000ULL) << 16; 161 uint64_t old_time = s->cpu_time; 162 163 s->cpu_time = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); 164 DB_PRINT("cpu time: %lld ns\n", (long long)old_time); 165 166 if (!s->cpu_time_valid || old_time == s->cpu_time) { 167 s->cpu_time_valid = 1; 168 return; 169 } 170 171 r = (int64_t)cadence_timer_get_steps(s, s->cpu_time - old_time); 172 x = (int64_t)s->reg_value + ((s->reg_count & COUNTER_CTRL_DEC) ? -r : r); 173 174 for (i = 0; i < 3; ++i) { 175 int64_t m = (int64_t)s->reg_match[i] << 16; 176 if (m > interval) { 177 continue; 178 } 179 /* check to see if match event has occurred. check m +/- interval 180 * to account for match events in wrap around cases */ 181 if (is_between(m, s->reg_value, x) || 182 is_between(m + interval, s->reg_value, x) || 183 is_between(m - interval, s->reg_value, x)) { 184 s->reg_intr |= (2 << i); 185 } 186 } 187 if ((x < 0) || (x >= interval)) { 188 s->reg_intr |= (s->reg_count & COUNTER_CTRL_INT) ? 189 COUNTER_INTR_IV : COUNTER_INTR_OV; 190 } 191 while (x < 0) { 192 x += interval; 193 } 194 s->reg_value = (uint32_t)(x % interval); 195 cadence_timer_update(s); 196 } 197 198 static void cadence_timer_tick(void *opaque) 199 { 200 CadenceTimerState *s = opaque; 201 202 DB_PRINT("\n"); 203 cadence_timer_sync(s); 204 cadence_timer_run(s); 205 } 206 207 static uint32_t cadence_ttc_read_imp(void *opaque, hwaddr offset) 208 { 209 CadenceTimerState *s = cadence_timer_from_addr(opaque, offset); 210 uint32_t value; 211 212 cadence_timer_sync(s); 213 cadence_timer_run(s); 214 215 switch (offset) { 216 case 0x00: /* clock control */ 217 case 0x04: 218 case 0x08: 219 return s->reg_clock; 220 221 case 0x0c: /* counter control */ 222 case 0x10: 223 case 0x14: 224 return s->reg_count; 225 226 case 0x18: /* counter value */ 227 case 0x1c: 228 case 0x20: 229 return (uint16_t)(s->reg_value >> 16); 230 231 case 0x24: /* reg_interval counter */ 232 case 0x28: 233 case 0x2c: 234 return s->reg_interval; 235 236 case 0x30: /* match 1 counter */ 237 case 0x34: 238 case 0x38: 239 return s->reg_match[0]; 240 241 case 0x3c: /* match 2 counter */ 242 case 0x40: 243 case 0x44: 244 return s->reg_match[1]; 245 246 case 0x48: /* match 3 counter */ 247 case 0x4c: 248 case 0x50: 249 return s->reg_match[2]; 250 251 case 0x54: /* interrupt register */ 252 case 0x58: 253 case 0x5c: 254 /* cleared after read */ 255 value = s->reg_intr; 256 s->reg_intr = 0; 257 cadence_timer_update(s); 258 return value; 259 260 case 0x60: /* interrupt enable */ 261 case 0x64: 262 case 0x68: 263 return s->reg_intr_en; 264 265 case 0x6c: 266 case 0x70: 267 case 0x74: 268 return s->reg_event_ctrl; 269 270 case 0x78: 271 case 0x7c: 272 case 0x80: 273 return s->reg_event; 274 275 default: 276 return 0; 277 } 278 } 279 280 static uint64_t cadence_ttc_read(void *opaque, hwaddr offset, 281 unsigned size) 282 { 283 uint32_t ret = cadence_ttc_read_imp(opaque, offset); 284 285 DB_PRINT("addr: %08x data: %08x\n", (unsigned)offset, (unsigned)ret); 286 return ret; 287 } 288 289 static void cadence_ttc_write(void *opaque, hwaddr offset, 290 uint64_t value, unsigned size) 291 { 292 CadenceTimerState *s = cadence_timer_from_addr(opaque, offset); 293 294 DB_PRINT("addr: %08x data %08x\n", (unsigned)offset, (unsigned)value); 295 296 cadence_timer_sync(s); 297 298 switch (offset) { 299 case 0x00: /* clock control */ 300 case 0x04: 301 case 0x08: 302 s->reg_clock = value & 0x3F; 303 break; 304 305 case 0x0c: /* counter control */ 306 case 0x10: 307 case 0x14: 308 if (value & COUNTER_CTRL_RST) { 309 s->reg_value = 0; 310 } 311 s->reg_count = value & 0x3f & ~COUNTER_CTRL_RST; 312 break; 313 314 case 0x24: /* interval register */ 315 case 0x28: 316 case 0x2c: 317 s->reg_interval = value & 0xffff; 318 break; 319 320 case 0x30: /* match register */ 321 case 0x34: 322 case 0x38: 323 s->reg_match[0] = value & 0xffff; 324 break; 325 326 case 0x3c: /* match register */ 327 case 0x40: 328 case 0x44: 329 s->reg_match[1] = value & 0xffff; 330 break; 331 332 case 0x48: /* match register */ 333 case 0x4c: 334 case 0x50: 335 s->reg_match[2] = value & 0xffff; 336 break; 337 338 case 0x54: /* interrupt register */ 339 case 0x58: 340 case 0x5c: 341 break; 342 343 case 0x60: /* interrupt enable */ 344 case 0x64: 345 case 0x68: 346 s->reg_intr_en = value & 0x3f; 347 break; 348 349 case 0x6c: /* event control */ 350 case 0x70: 351 case 0x74: 352 s->reg_event_ctrl = value & 0x07; 353 break; 354 355 default: 356 return; 357 } 358 359 cadence_timer_run(s); 360 cadence_timer_update(s); 361 } 362 363 static const MemoryRegionOps cadence_ttc_ops = { 364 .read = cadence_ttc_read, 365 .write = cadence_ttc_write, 366 .endianness = DEVICE_NATIVE_ENDIAN, 367 }; 368 369 static void cadence_timer_reset(CadenceTimerState *s) 370 { 371 s->reg_count = 0x21; 372 } 373 374 static void cadence_timer_init(uint32_t freq, CadenceTimerState *s) 375 { 376 memset(s, 0, sizeof(CadenceTimerState)); 377 s->freq = freq; 378 379 cadence_timer_reset(s); 380 381 s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, cadence_timer_tick, s); 382 } 383 384 static void cadence_ttc_init(Object *obj) 385 { 386 CadenceTTCState *s = CADENCE_TTC(obj); 387 388 memory_region_init_io(&s->iomem, obj, &cadence_ttc_ops, s, 389 "timer", 0x1000); 390 sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->iomem); 391 } 392 393 static void cadence_ttc_realize(DeviceState *dev, Error **errp) 394 { 395 CadenceTTCState *s = CADENCE_TTC(dev); 396 int i; 397 398 for (i = 0; i < 3; ++i) { 399 cadence_timer_init(133000000, &s->timer[i]); 400 sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->timer[i].irq); 401 } 402 } 403 404 static int cadence_timer_pre_save(void *opaque) 405 { 406 cadence_timer_sync((CadenceTimerState *)opaque); 407 408 return 0; 409 } 410 411 static int cadence_timer_post_load(void *opaque, int version_id) 412 { 413 CadenceTimerState *s = opaque; 414 415 s->cpu_time_valid = 0; 416 cadence_timer_sync(s); 417 cadence_timer_run(s); 418 cadence_timer_update(s); 419 return 0; 420 } 421 422 static const VMStateDescription vmstate_cadence_timer = { 423 .name = "cadence_timer", 424 .version_id = 1, 425 .minimum_version_id = 1, 426 .pre_save = cadence_timer_pre_save, 427 .post_load = cadence_timer_post_load, 428 .fields = (VMStateField[]) { 429 VMSTATE_UINT32(reg_clock, CadenceTimerState), 430 VMSTATE_UINT32(reg_count, CadenceTimerState), 431 VMSTATE_UINT32(reg_value, CadenceTimerState), 432 VMSTATE_UINT16(reg_interval, CadenceTimerState), 433 VMSTATE_UINT16_ARRAY(reg_match, CadenceTimerState, 3), 434 VMSTATE_UINT32(reg_intr, CadenceTimerState), 435 VMSTATE_UINT32(reg_intr_en, CadenceTimerState), 436 VMSTATE_UINT32(reg_event_ctrl, CadenceTimerState), 437 VMSTATE_UINT32(reg_event, CadenceTimerState), 438 VMSTATE_END_OF_LIST() 439 } 440 }; 441 442 static const VMStateDescription vmstate_cadence_ttc = { 443 .name = "cadence_TTC", 444 .version_id = 1, 445 .minimum_version_id = 1, 446 .fields = (VMStateField[]) { 447 VMSTATE_STRUCT_ARRAY(timer, CadenceTTCState, 3, 0, 448 vmstate_cadence_timer, 449 CadenceTimerState), 450 VMSTATE_END_OF_LIST() 451 } 452 }; 453 454 static void cadence_ttc_class_init(ObjectClass *klass, void *data) 455 { 456 DeviceClass *dc = DEVICE_CLASS(klass); 457 458 dc->vmsd = &vmstate_cadence_ttc; 459 dc->realize = cadence_ttc_realize; 460 } 461 462 static const TypeInfo cadence_ttc_info = { 463 .name = TYPE_CADENCE_TTC, 464 .parent = TYPE_SYS_BUS_DEVICE, 465 .instance_size = sizeof(CadenceTTCState), 466 .instance_init = cadence_ttc_init, 467 .class_init = cadence_ttc_class_init, 468 }; 469 470 static void cadence_ttc_register_types(void) 471 { 472 type_register_static(&cadence_ttc_info); 473 } 474 475 type_init(cadence_ttc_register_types)