arm_timer.c (11382B)
1/* 2 * ARM PrimeCell Timer modules. 3 * 4 * Copyright (c) 2005-2006 CodeSourcery. 5 * Written by Paul Brook 6 * 7 * This code is licensed under the GPL. 8 */ 9 10#include "qemu/osdep.h" 11#include "hw/sysbus.h" 12#include "migration/vmstate.h" 13#include "qemu/timer.h" 14#include "hw/irq.h" 15#include "hw/ptimer.h" 16#include "hw/qdev-properties.h" 17#include "qemu/module.h" 18#include "qemu/log.h" 19#include "qom/object.h" 20 21/* Common timer implementation. */ 22 23#define TIMER_CTRL_ONESHOT (1 << 0) 24#define TIMER_CTRL_32BIT (1 << 1) 25#define TIMER_CTRL_DIV1 (0 << 2) 26#define TIMER_CTRL_DIV16 (1 << 2) 27#define TIMER_CTRL_DIV256 (2 << 2) 28#define TIMER_CTRL_IE (1 << 5) 29#define TIMER_CTRL_PERIODIC (1 << 6) 30#define TIMER_CTRL_ENABLE (1 << 7) 31 32typedef struct { 33 ptimer_state *timer; 34 uint32_t control; 35 uint32_t limit; 36 int freq; 37 int int_level; 38 qemu_irq irq; 39} arm_timer_state; 40 41/* Check all active timers, and schedule the next timer interrupt. */ 42 43static void arm_timer_update(arm_timer_state *s) 44{ 45 /* Update interrupts. */ 46 if (s->int_level && (s->control & TIMER_CTRL_IE)) { 47 qemu_irq_raise(s->irq); 48 } else { 49 qemu_irq_lower(s->irq); 50 } 51} 52 53static uint32_t arm_timer_read(void *opaque, hwaddr offset) 54{ 55 arm_timer_state *s = (arm_timer_state *)opaque; 56 57 switch (offset >> 2) { 58 case 0: /* TimerLoad */ 59 case 6: /* TimerBGLoad */ 60 return s->limit; 61 case 1: /* TimerValue */ 62 return ptimer_get_count(s->timer); 63 case 2: /* TimerControl */ 64 return s->control; 65 case 4: /* TimerRIS */ 66 return s->int_level; 67 case 5: /* TimerMIS */ 68 if ((s->control & TIMER_CTRL_IE) == 0) 69 return 0; 70 return s->int_level; 71 default: 72 qemu_log_mask(LOG_GUEST_ERROR, 73 "%s: Bad offset %x\n", __func__, (int)offset); 74 return 0; 75 } 76} 77 78/* 79 * Reset the timer limit after settings have changed. 80 * May only be called from inside a ptimer transaction block. 81 */ 82static void arm_timer_recalibrate(arm_timer_state *s, int reload) 83{ 84 uint32_t limit; 85 86 if ((s->control & (TIMER_CTRL_PERIODIC | TIMER_CTRL_ONESHOT)) == 0) { 87 /* Free running. */ 88 if (s->control & TIMER_CTRL_32BIT) 89 limit = 0xffffffff; 90 else 91 limit = 0xffff; 92 } else { 93 /* Periodic. */ 94 limit = s->limit; 95 } 96 ptimer_set_limit(s->timer, limit, reload); 97} 98 99static void arm_timer_write(void *opaque, hwaddr offset, 100 uint32_t value) 101{ 102 arm_timer_state *s = (arm_timer_state *)opaque; 103 int freq; 104 105 switch (offset >> 2) { 106 case 0: /* TimerLoad */ 107 s->limit = value; 108 ptimer_transaction_begin(s->timer); 109 arm_timer_recalibrate(s, 1); 110 ptimer_transaction_commit(s->timer); 111 break; 112 case 1: /* TimerValue */ 113 /* ??? Linux seems to want to write to this readonly register. 114 Ignore it. */ 115 break; 116 case 2: /* TimerControl */ 117 ptimer_transaction_begin(s->timer); 118 if (s->control & TIMER_CTRL_ENABLE) { 119 /* Pause the timer if it is running. This may cause some 120 inaccuracy dure to rounding, but avoids a whole lot of other 121 messyness. */ 122 ptimer_stop(s->timer); 123 } 124 s->control = value; 125 freq = s->freq; 126 /* ??? Need to recalculate expiry time after changing divisor. */ 127 switch ((value >> 2) & 3) { 128 case 1: freq >>= 4; break; 129 case 2: freq >>= 8; break; 130 } 131 arm_timer_recalibrate(s, s->control & TIMER_CTRL_ENABLE); 132 ptimer_set_freq(s->timer, freq); 133 if (s->control & TIMER_CTRL_ENABLE) { 134 /* Restart the timer if still enabled. */ 135 ptimer_run(s->timer, (s->control & TIMER_CTRL_ONESHOT) != 0); 136 } 137 ptimer_transaction_commit(s->timer); 138 break; 139 case 3: /* TimerIntClr */ 140 s->int_level = 0; 141 break; 142 case 6: /* TimerBGLoad */ 143 s->limit = value; 144 ptimer_transaction_begin(s->timer); 145 arm_timer_recalibrate(s, 0); 146 ptimer_transaction_commit(s->timer); 147 break; 148 default: 149 qemu_log_mask(LOG_GUEST_ERROR, 150 "%s: Bad offset %x\n", __func__, (int)offset); 151 } 152 arm_timer_update(s); 153} 154 155static void arm_timer_tick(void *opaque) 156{ 157 arm_timer_state *s = (arm_timer_state *)opaque; 158 s->int_level = 1; 159 arm_timer_update(s); 160} 161 162static const VMStateDescription vmstate_arm_timer = { 163 .name = "arm_timer", 164 .version_id = 1, 165 .minimum_version_id = 1, 166 .fields = (VMStateField[]) { 167 VMSTATE_UINT32(control, arm_timer_state), 168 VMSTATE_UINT32(limit, arm_timer_state), 169 VMSTATE_INT32(int_level, arm_timer_state), 170 VMSTATE_PTIMER(timer, arm_timer_state), 171 VMSTATE_END_OF_LIST() 172 } 173}; 174 175static arm_timer_state *arm_timer_init(uint32_t freq) 176{ 177 arm_timer_state *s; 178 179 s = (arm_timer_state *)g_malloc0(sizeof(arm_timer_state)); 180 s->freq = freq; 181 s->control = TIMER_CTRL_IE; 182 183 s->timer = ptimer_init(arm_timer_tick, s, PTIMER_POLICY_DEFAULT); 184 vmstate_register(NULL, VMSTATE_INSTANCE_ID_ANY, &vmstate_arm_timer, s); 185 return s; 186} 187 188/* 189 * ARM PrimeCell SP804 dual timer module. 190 * Docs at 191 * https://developer.arm.com/documentation/ddi0271/latest/ 192 */ 193 194#define TYPE_SP804 "sp804" 195OBJECT_DECLARE_SIMPLE_TYPE(SP804State, SP804) 196 197struct SP804State { 198 SysBusDevice parent_obj; 199 200 MemoryRegion iomem; 201 arm_timer_state *timer[2]; 202 uint32_t freq0, freq1; 203 int level[2]; 204 qemu_irq irq; 205}; 206 207static const uint8_t sp804_ids[] = { 208 /* Timer ID */ 209 0x04, 0x18, 0x14, 0, 210 /* PrimeCell ID */ 211 0xd, 0xf0, 0x05, 0xb1 212}; 213 214/* Merge the IRQs from the two component devices. */ 215static void sp804_set_irq(void *opaque, int irq, int level) 216{ 217 SP804State *s = (SP804State *)opaque; 218 219 s->level[irq] = level; 220 qemu_set_irq(s->irq, s->level[0] || s->level[1]); 221} 222 223static uint64_t sp804_read(void *opaque, hwaddr offset, 224 unsigned size) 225{ 226 SP804State *s = (SP804State *)opaque; 227 228 if (offset < 0x20) { 229 return arm_timer_read(s->timer[0], offset); 230 } 231 if (offset < 0x40) { 232 return arm_timer_read(s->timer[1], offset - 0x20); 233 } 234 235 /* TimerPeriphID */ 236 if (offset >= 0xfe0 && offset <= 0xffc) { 237 return sp804_ids[(offset - 0xfe0) >> 2]; 238 } 239 240 switch (offset) { 241 /* Integration Test control registers, which we won't support */ 242 case 0xf00: /* TimerITCR */ 243 case 0xf04: /* TimerITOP (strictly write only but..) */ 244 qemu_log_mask(LOG_UNIMP, 245 "%s: integration test registers unimplemented\n", 246 __func__); 247 return 0; 248 } 249 250 qemu_log_mask(LOG_GUEST_ERROR, 251 "%s: Bad offset %x\n", __func__, (int)offset); 252 return 0; 253} 254 255static void sp804_write(void *opaque, hwaddr offset, 256 uint64_t value, unsigned size) 257{ 258 SP804State *s = (SP804State *)opaque; 259 260 if (offset < 0x20) { 261 arm_timer_write(s->timer[0], offset, value); 262 return; 263 } 264 265 if (offset < 0x40) { 266 arm_timer_write(s->timer[1], offset - 0x20, value); 267 return; 268 } 269 270 /* Technically we could be writing to the Test Registers, but not likely */ 271 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %x\n", 272 __func__, (int)offset); 273} 274 275static const MemoryRegionOps sp804_ops = { 276 .read = sp804_read, 277 .write = sp804_write, 278 .endianness = DEVICE_NATIVE_ENDIAN, 279}; 280 281static const VMStateDescription vmstate_sp804 = { 282 .name = "sp804", 283 .version_id = 1, 284 .minimum_version_id = 1, 285 .fields = (VMStateField[]) { 286 VMSTATE_INT32_ARRAY(level, SP804State, 2), 287 VMSTATE_END_OF_LIST() 288 } 289}; 290 291static void sp804_init(Object *obj) 292{ 293 SP804State *s = SP804(obj); 294 SysBusDevice *sbd = SYS_BUS_DEVICE(obj); 295 296 sysbus_init_irq(sbd, &s->irq); 297 memory_region_init_io(&s->iomem, obj, &sp804_ops, s, 298 "sp804", 0x1000); 299 sysbus_init_mmio(sbd, &s->iomem); 300} 301 302static void sp804_realize(DeviceState *dev, Error **errp) 303{ 304 SP804State *s = SP804(dev); 305 306 s->timer[0] = arm_timer_init(s->freq0); 307 s->timer[1] = arm_timer_init(s->freq1); 308 s->timer[0]->irq = qemu_allocate_irq(sp804_set_irq, s, 0); 309 s->timer[1]->irq = qemu_allocate_irq(sp804_set_irq, s, 1); 310} 311 312/* Integrator/CP timer module. */ 313 314#define TYPE_INTEGRATOR_PIT "integrator_pit" 315OBJECT_DECLARE_SIMPLE_TYPE(icp_pit_state, INTEGRATOR_PIT) 316 317struct icp_pit_state { 318 SysBusDevice parent_obj; 319 320 MemoryRegion iomem; 321 arm_timer_state *timer[3]; 322}; 323 324static uint64_t icp_pit_read(void *opaque, hwaddr offset, 325 unsigned size) 326{ 327 icp_pit_state *s = (icp_pit_state *)opaque; 328 int n; 329 330 /* ??? Don't know the PrimeCell ID for this device. */ 331 n = offset >> 8; 332 if (n > 2) { 333 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad timer %d\n", __func__, n); 334 return 0; 335 } 336 337 return arm_timer_read(s->timer[n], offset & 0xff); 338} 339 340static void icp_pit_write(void *opaque, hwaddr offset, 341 uint64_t value, unsigned size) 342{ 343 icp_pit_state *s = (icp_pit_state *)opaque; 344 int n; 345 346 n = offset >> 8; 347 if (n > 2) { 348 qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad timer %d\n", __func__, n); 349 return; 350 } 351 352 arm_timer_write(s->timer[n], offset & 0xff, value); 353} 354 355static const MemoryRegionOps icp_pit_ops = { 356 .read = icp_pit_read, 357 .write = icp_pit_write, 358 .endianness = DEVICE_NATIVE_ENDIAN, 359}; 360 361static void icp_pit_init(Object *obj) 362{ 363 icp_pit_state *s = INTEGRATOR_PIT(obj); 364 SysBusDevice *dev = SYS_BUS_DEVICE(obj); 365 366 /* Timer 0 runs at the system clock speed (40MHz). */ 367 s->timer[0] = arm_timer_init(40000000); 368 /* The other two timers run at 1MHz. */ 369 s->timer[1] = arm_timer_init(1000000); 370 s->timer[2] = arm_timer_init(1000000); 371 372 sysbus_init_irq(dev, &s->timer[0]->irq); 373 sysbus_init_irq(dev, &s->timer[1]->irq); 374 sysbus_init_irq(dev, &s->timer[2]->irq); 375 376 memory_region_init_io(&s->iomem, obj, &icp_pit_ops, s, 377 "icp_pit", 0x1000); 378 sysbus_init_mmio(dev, &s->iomem); 379 /* This device has no state to save/restore. The component timers will 380 save themselves. */ 381} 382 383static const TypeInfo icp_pit_info = { 384 .name = TYPE_INTEGRATOR_PIT, 385 .parent = TYPE_SYS_BUS_DEVICE, 386 .instance_size = sizeof(icp_pit_state), 387 .instance_init = icp_pit_init, 388}; 389 390static Property sp804_properties[] = { 391 DEFINE_PROP_UINT32("freq0", SP804State, freq0, 1000000), 392 DEFINE_PROP_UINT32("freq1", SP804State, freq1, 1000000), 393 DEFINE_PROP_END_OF_LIST(), 394}; 395 396static void sp804_class_init(ObjectClass *klass, void *data) 397{ 398 DeviceClass *k = DEVICE_CLASS(klass); 399 400 k->realize = sp804_realize; 401 device_class_set_props(k, sp804_properties); 402 k->vmsd = &vmstate_sp804; 403} 404 405static const TypeInfo sp804_info = { 406 .name = TYPE_SP804, 407 .parent = TYPE_SYS_BUS_DEVICE, 408 .instance_size = sizeof(SP804State), 409 .instance_init = sp804_init, 410 .class_init = sp804_class_init, 411}; 412 413static void arm_timer_register_types(void) 414{ 415 type_register_static(&icp_pit_info); 416 type_register_static(&sp804_info); 417} 418 419type_init(arm_timer_register_types)