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 "hw/sysbus.h" 20 #include "qemu/timer.h" 21 22 #ifdef CADENCE_TTC_ERR_DEBUG 23 #define DB_PRINT(...) do { \ 24 fprintf(stderr, ": %s: ", __func__); \ 25 fprintf(stderr, ## __VA_ARGS__); \ 26 } while (0); 27 #else 28 #define DB_PRINT(...) 29 #endif 30 31 #define COUNTER_INTR_IV 0x00000001 32 #define COUNTER_INTR_M1 0x00000002 33 #define COUNTER_INTR_M2 0x00000004 34 #define COUNTER_INTR_M3 0x00000008 35 #define COUNTER_INTR_OV 0x00000010 36 #define COUNTER_INTR_EV 0x00000020 37 38 #define COUNTER_CTRL_DIS 0x00000001 39 #define COUNTER_CTRL_INT 0x00000002 40 #define COUNTER_CTRL_DEC 0x00000004 41 #define COUNTER_CTRL_MATCH 0x00000008 42 #define COUNTER_CTRL_RST 0x00000010 43 44 #define CLOCK_CTRL_PS_EN 0x00000001 45 #define CLOCK_CTRL_PS_V 0x0000001e 46 47 typedef struct { 48 QEMUTimer *timer; 49 int freq; 50 51 uint32_t reg_clock; 52 uint32_t reg_count; 53 uint32_t reg_value; 54 uint16_t reg_interval; 55 uint16_t reg_match[3]; 56 uint32_t reg_intr; 57 uint32_t reg_intr_en; 58 uint32_t reg_event_ctrl; 59 uint32_t reg_event; 60 61 uint64_t cpu_time; 62 unsigned int cpu_time_valid; 63 64 qemu_irq irq; 65 } CadenceTimerState; 66 67 #define TYPE_CADENCE_TTC "cadence_ttc" 68 #define CADENCE_TTC(obj) \ 69 OBJECT_CHECK(CadenceTTCState, (obj), TYPE_CADENCE_TTC) 70 71 typedef struct CadenceTTCState { 72 SysBusDevice parent_obj; 73 74 MemoryRegion iomem; 75 CadenceTimerState timer[3]; 76 } CadenceTTCState; 77 78 static void cadence_timer_update(CadenceTimerState *s) 79 { 80 qemu_set_irq(s->irq, !!(s->reg_intr & s->reg_intr_en)); 81 } 82 83 static CadenceTimerState *cadence_timer_from_addr(void *opaque, 84 hwaddr offset) 85 { 86 unsigned int index; 87 CadenceTTCState *s = (CadenceTTCState *)opaque; 88 89 index = (offset >> 2) % 3; 90 91 return &s->timer[index]; 92 } 93 94 static uint64_t cadence_timer_get_ns(CadenceTimerState *s, uint64_t timer_steps) 95 { 96 /* timer_steps has max value of 0x100000000. double check it 97 * (or overflow can happen below) */ 98 assert(timer_steps <= 1ULL << 32); 99 100 uint64_t r = timer_steps * 1000000000ULL; 101 if (s->reg_clock & CLOCK_CTRL_PS_EN) { 102 r >>= 16 - (((s->reg_clock & CLOCK_CTRL_PS_V) >> 1) + 1); 103 } else { 104 r >>= 16; 105 } 106 r /= (uint64_t)s->freq; 107 return r; 108 } 109 110 static uint64_t cadence_timer_get_steps(CadenceTimerState *s, uint64_t ns) 111 { 112 uint64_t to_divide = 1000000000ULL; 113 114 uint64_t r = ns; 115 /* for very large intervals (> 8s) do some division first to stop 116 * overflow (costs some prescision) */ 117 while (r >= 8ULL << 30 && to_divide > 1) { 118 r /= 1000; 119 to_divide /= 1000; 120 } 121 r <<= 16; 122 /* keep early-dividing as needed */ 123 while (r >= 8ULL << 30 && to_divide > 1) { 124 r /= 1000; 125 to_divide /= 1000; 126 } 127 r *= (uint64_t)s->freq; 128 if (s->reg_clock & CLOCK_CTRL_PS_EN) { 129 r /= 1 << (((s->reg_clock & CLOCK_CTRL_PS_V) >> 1) + 1); 130 } 131 132 r /= to_divide; 133 return r; 134 } 135 136 /* determine if x is in between a and b, exclusive of a, inclusive of b */ 137 138 static inline int64_t is_between(int64_t x, int64_t a, int64_t b) 139 { 140 if (a < b) { 141 return x > a && x <= b; 142 } 143 return x < a && x >= b; 144 } 145 146 static void cadence_timer_run(CadenceTimerState *s) 147 { 148 int i; 149 int64_t event_interval, next_value; 150 151 assert(s->cpu_time_valid); /* cadence_timer_sync must be called first */ 152 153 if (s->reg_count & COUNTER_CTRL_DIS) { 154 s->cpu_time_valid = 0; 155 return; 156 } 157 158 { /* figure out what's going to happen next (rollover or match) */ 159 int64_t interval = (uint64_t)((s->reg_count & COUNTER_CTRL_INT) ? 160 (int64_t)s->reg_interval + 1 : 0x10000ULL) << 16; 161 next_value = (s->reg_count & COUNTER_CTRL_DEC) ? -1ULL : interval; 162 for (i = 0; i < 3; ++i) { 163 int64_t cand = (uint64_t)s->reg_match[i] << 16; 164 if (is_between(cand, (uint64_t)s->reg_value, next_value)) { 165 next_value = cand; 166 } 167 } 168 } 169 DB_PRINT("next timer event value: %09llx\n", 170 (unsigned long long)next_value); 171 172 event_interval = next_value - (int64_t)s->reg_value; 173 event_interval = (event_interval < 0) ? -event_interval : event_interval; 174 175 timer_mod(s->timer, s->cpu_time + 176 cadence_timer_get_ns(s, event_interval)); 177 } 178 179 static void cadence_timer_sync(CadenceTimerState *s) 180 { 181 int i; 182 int64_t r, x; 183 int64_t interval = ((s->reg_count & COUNTER_CTRL_INT) ? 184 (int64_t)s->reg_interval + 1 : 0x10000ULL) << 16; 185 uint64_t old_time = s->cpu_time; 186 187 s->cpu_time = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); 188 DB_PRINT("cpu time: %lld ns\n", (long long)old_time); 189 190 if (!s->cpu_time_valid || old_time == s->cpu_time) { 191 s->cpu_time_valid = 1; 192 return; 193 } 194 195 r = (int64_t)cadence_timer_get_steps(s, s->cpu_time - old_time); 196 x = (int64_t)s->reg_value + ((s->reg_count & COUNTER_CTRL_DEC) ? -r : r); 197 198 for (i = 0; i < 3; ++i) { 199 int64_t m = (int64_t)s->reg_match[i] << 16; 200 if (m > interval) { 201 continue; 202 } 203 /* check to see if match event has occurred. check m +/- interval 204 * to account for match events in wrap around cases */ 205 if (is_between(m, s->reg_value, x) || 206 is_between(m + interval, s->reg_value, x) || 207 is_between(m - interval, s->reg_value, x)) { 208 s->reg_intr |= (2 << i); 209 } 210 } 211 while (x < 0) { 212 x += interval; 213 } 214 s->reg_value = (uint32_t)(x % interval); 215 216 if (s->reg_value != x) { 217 s->reg_intr |= (s->reg_count & COUNTER_CTRL_INT) ? 218 COUNTER_INTR_IV : COUNTER_INTR_OV; 219 } 220 cadence_timer_update(s); 221 } 222 223 static void cadence_timer_tick(void *opaque) 224 { 225 CadenceTimerState *s = opaque; 226 227 DB_PRINT("\n"); 228 cadence_timer_sync(s); 229 cadence_timer_run(s); 230 } 231 232 static uint32_t cadence_ttc_read_imp(void *opaque, hwaddr offset) 233 { 234 CadenceTimerState *s = cadence_timer_from_addr(opaque, offset); 235 uint32_t value; 236 237 cadence_timer_sync(s); 238 cadence_timer_run(s); 239 240 switch (offset) { 241 case 0x00: /* clock control */ 242 case 0x04: 243 case 0x08: 244 return s->reg_clock; 245 246 case 0x0c: /* counter control */ 247 case 0x10: 248 case 0x14: 249 return s->reg_count; 250 251 case 0x18: /* counter value */ 252 case 0x1c: 253 case 0x20: 254 return (uint16_t)(s->reg_value >> 16); 255 256 case 0x24: /* reg_interval counter */ 257 case 0x28: 258 case 0x2c: 259 return s->reg_interval; 260 261 case 0x30: /* match 1 counter */ 262 case 0x34: 263 case 0x38: 264 return s->reg_match[0]; 265 266 case 0x3c: /* match 2 counter */ 267 case 0x40: 268 case 0x44: 269 return s->reg_match[1]; 270 271 case 0x48: /* match 3 counter */ 272 case 0x4c: 273 case 0x50: 274 return s->reg_match[2]; 275 276 case 0x54: /* interrupt register */ 277 case 0x58: 278 case 0x5c: 279 /* cleared after read */ 280 value = s->reg_intr; 281 s->reg_intr = 0; 282 cadence_timer_update(s); 283 return value; 284 285 case 0x60: /* interrupt enable */ 286 case 0x64: 287 case 0x68: 288 return s->reg_intr_en; 289 290 case 0x6c: 291 case 0x70: 292 case 0x74: 293 return s->reg_event_ctrl; 294 295 case 0x78: 296 case 0x7c: 297 case 0x80: 298 return s->reg_event; 299 300 default: 301 return 0; 302 } 303 } 304 305 static uint64_t cadence_ttc_read(void *opaque, hwaddr offset, 306 unsigned size) 307 { 308 uint32_t ret = cadence_ttc_read_imp(opaque, offset); 309 310 DB_PRINT("addr: %08x data: %08x\n", (unsigned)offset, (unsigned)ret); 311 return ret; 312 } 313 314 static void cadence_ttc_write(void *opaque, hwaddr offset, 315 uint64_t value, unsigned size) 316 { 317 CadenceTimerState *s = cadence_timer_from_addr(opaque, offset); 318 319 DB_PRINT("addr: %08x data %08x\n", (unsigned)offset, (unsigned)value); 320 321 cadence_timer_sync(s); 322 323 switch (offset) { 324 case 0x00: /* clock control */ 325 case 0x04: 326 case 0x08: 327 s->reg_clock = value & 0x3F; 328 break; 329 330 case 0x0c: /* counter control */ 331 case 0x10: 332 case 0x14: 333 if (value & COUNTER_CTRL_RST) { 334 s->reg_value = 0; 335 } 336 s->reg_count = value & 0x3f & ~COUNTER_CTRL_RST; 337 break; 338 339 case 0x24: /* interval register */ 340 case 0x28: 341 case 0x2c: 342 s->reg_interval = value & 0xffff; 343 break; 344 345 case 0x30: /* match register */ 346 case 0x34: 347 case 0x38: 348 s->reg_match[0] = value & 0xffff; 349 break; 350 351 case 0x3c: /* match register */ 352 case 0x40: 353 case 0x44: 354 s->reg_match[1] = value & 0xffff; 355 break; 356 357 case 0x48: /* match register */ 358 case 0x4c: 359 case 0x50: 360 s->reg_match[2] = value & 0xffff; 361 break; 362 363 case 0x54: /* interrupt register */ 364 case 0x58: 365 case 0x5c: 366 break; 367 368 case 0x60: /* interrupt enable */ 369 case 0x64: 370 case 0x68: 371 s->reg_intr_en = value & 0x3f; 372 break; 373 374 case 0x6c: /* event control */ 375 case 0x70: 376 case 0x74: 377 s->reg_event_ctrl = value & 0x07; 378 break; 379 380 default: 381 return; 382 } 383 384 cadence_timer_run(s); 385 cadence_timer_update(s); 386 } 387 388 static const MemoryRegionOps cadence_ttc_ops = { 389 .read = cadence_ttc_read, 390 .write = cadence_ttc_write, 391 .endianness = DEVICE_NATIVE_ENDIAN, 392 }; 393 394 static void cadence_timer_reset(CadenceTimerState *s) 395 { 396 s->reg_count = 0x21; 397 } 398 399 static void cadence_timer_init(uint32_t freq, CadenceTimerState *s) 400 { 401 memset(s, 0, sizeof(CadenceTimerState)); 402 s->freq = freq; 403 404 cadence_timer_reset(s); 405 406 s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, cadence_timer_tick, s); 407 } 408 409 static int cadence_ttc_init(SysBusDevice *dev) 410 { 411 CadenceTTCState *s = CADENCE_TTC(dev); 412 int i; 413 414 for (i = 0; i < 3; ++i) { 415 cadence_timer_init(133000000, &s->timer[i]); 416 sysbus_init_irq(dev, &s->timer[i].irq); 417 } 418 419 memory_region_init_io(&s->iomem, OBJECT(s), &cadence_ttc_ops, s, 420 "timer", 0x1000); 421 sysbus_init_mmio(dev, &s->iomem); 422 423 return 0; 424 } 425 426 static void cadence_timer_pre_save(void *opaque) 427 { 428 cadence_timer_sync((CadenceTimerState *)opaque); 429 } 430 431 static int cadence_timer_post_load(void *opaque, int version_id) 432 { 433 CadenceTimerState *s = opaque; 434 435 s->cpu_time_valid = 0; 436 cadence_timer_sync(s); 437 cadence_timer_run(s); 438 cadence_timer_update(s); 439 return 0; 440 } 441 442 static const VMStateDescription vmstate_cadence_timer = { 443 .name = "cadence_timer", 444 .version_id = 1, 445 .minimum_version_id = 1, 446 .minimum_version_id_old = 1, 447 .pre_save = cadence_timer_pre_save, 448 .post_load = cadence_timer_post_load, 449 .fields = (VMStateField[]) { 450 VMSTATE_UINT32(reg_clock, CadenceTimerState), 451 VMSTATE_UINT32(reg_count, CadenceTimerState), 452 VMSTATE_UINT32(reg_value, CadenceTimerState), 453 VMSTATE_UINT16(reg_interval, CadenceTimerState), 454 VMSTATE_UINT16_ARRAY(reg_match, CadenceTimerState, 3), 455 VMSTATE_UINT32(reg_intr, CadenceTimerState), 456 VMSTATE_UINT32(reg_intr_en, CadenceTimerState), 457 VMSTATE_UINT32(reg_event_ctrl, CadenceTimerState), 458 VMSTATE_UINT32(reg_event, CadenceTimerState), 459 VMSTATE_END_OF_LIST() 460 } 461 }; 462 463 static const VMStateDescription vmstate_cadence_ttc = { 464 .name = "cadence_TTC", 465 .version_id = 1, 466 .minimum_version_id = 1, 467 .minimum_version_id_old = 1, 468 .fields = (VMStateField[]) { 469 VMSTATE_STRUCT_ARRAY(timer, CadenceTTCState, 3, 0, 470 vmstate_cadence_timer, 471 CadenceTimerState), 472 VMSTATE_END_OF_LIST() 473 } 474 }; 475 476 static void cadence_ttc_class_init(ObjectClass *klass, void *data) 477 { 478 DeviceClass *dc = DEVICE_CLASS(klass); 479 SysBusDeviceClass *sdc = SYS_BUS_DEVICE_CLASS(klass); 480 481 sdc->init = cadence_ttc_init; 482 dc->vmsd = &vmstate_cadence_ttc; 483 } 484 485 static const TypeInfo cadence_ttc_info = { 486 .name = TYPE_CADENCE_TTC, 487 .parent = TYPE_SYS_BUS_DEVICE, 488 .instance_size = sizeof(CadenceTTCState), 489 .class_init = cadence_ttc_class_init, 490 }; 491 492 static void cadence_ttc_register_types(void) 493 { 494 type_register_static(&cadence_ttc_info); 495 } 496 497 type_init(cadence_ttc_register_types) 498