hw/timer/hpet.c

   1 /*
   2  *  High Precision Event Timer emulation
   3  *
   4  *  Copyright (c) 2007 Alexander Graf
   5  *  Copyright (c) 2008 IBM Corporation
   6  *
   7  *  Authors: Beth Kon <bkon@us.ibm.com>
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2 of the License, or (at your option) any later version.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  21  *
  22  * *****************************************************************
  23  *
  24  * This driver attempts to emulate an HPET device in software.
  25  */
  26
  27 #include "qemu/osdep.h"
  28 #include "hw/hw.h"
  29 #include "hw/i386/pc.h"
  30 #include "ui/console.h"
  31 #include "qapi/error.h"
  32 #include "qemu/error-report.h"
  33 #include "qemu/timer.h"
  34 #include "hw/timer/hpet.h"
  35 #include "hw/sysbus.h"
  36 #include "hw/timer/mc146818rtc.h"
  37 #include "hw/timer/i8254.h"
  38
  39 //#define HPET_DEBUG
  40 #ifdef HPET_DEBUG
  41 #define DPRINTF printf
  42 #else
  43 #define DPRINTF(...)
  44 #endif
  45
  46 #define HPET_MSI_SUPPORT        0
  47
  48 #define HPET(obj) OBJECT_CHECK(HPETState, (obj), TYPE_HPET)
  49
  50 struct HPETState;
  51 typedef struct HPETTimer {  /* timers */
  52     uint8_t tn;             /*timer number*/
  53     QEMUTimer *qemu_timer;
  54     struct HPETState *state;
  55     /* Memory-mapped, software visible timer registers */
  56     uint64_t config;        /* configuration/cap */
  57     uint64_t cmp;           /* comparator */
  58     uint64_t fsb;           /* FSB route */
  59     /* Hidden register state */
  60     uint64_t period;        /* Last value written to comparator */
  61     uint8_t wrap_flag;      /* timer pop will indicate wrap for one-shot 32-bit
  62                              * mode. Next pop will be actual timer expiration.
  63                              */
  64 } HPETTimer;
  65
  66 typedef struct HPETState {
  67     /*< private >*/
  68     SysBusDevice parent_obj;
  69     /*< public >*/
  70
  71     MemoryRegion iomem;
  72     uint64_t hpet_offset;
  73     bool hpet_offset_saved;
  74     qemu_irq irqs[HPET_NUM_IRQ_ROUTES];
  75     uint32_t flags;
  76     uint8_t rtc_irq_level;
  77     qemu_irq pit_enabled;
  78     uint8_t num_timers;
  79     uint32_t intcap;
  80     HPETTimer timer[HPET_MAX_TIMERS];
  81
  82     /* Memory-mapped, software visible registers */
  83     uint64_t capability;        /* capabilities */
  84     uint64_t config;            /* configuration */
  85     uint64_t isr;               /* interrupt status reg */
  86     uint64_t hpet_counter;      /* main counter */
  87     uint8_t  hpet_id;           /* instance id */
  88 } HPETState;
  89
  90 static uint32_t hpet_in_legacy_mode(HPETState *s)
  91 {
  92     return s->config & HPET_CFG_LEGACY;
  93 }
  94
  95 static uint32_t timer_int_route(struct HPETTimer *timer)
  96 {
  97     return (timer->config & HPET_TN_INT_ROUTE_MASK) >> HPET_TN_INT_ROUTE_SHIFT;
  98 }
  99
 100 static uint32_t timer_fsb_route(HPETTimer *t)
 101 {
 102     return t->config & HPET_TN_FSB_ENABLE;
 103 }
 104
 105 static uint32_t hpet_enabled(HPETState *s)
 106 {
 107     return s->config & HPET_CFG_ENABLE;
 108 }
 109
 110 static uint32_t timer_is_periodic(HPETTimer *t)
 111 {
 112     return t->config & HPET_TN_PERIODIC;
 113 }
 114
 115 static uint32_t timer_enabled(HPETTimer *t)
 116 {
 117     return t->config & HPET_TN_ENABLE;
 118 }
 119
 120 static uint32_t hpet_time_after(uint64_t a, uint64_t b)
 121 {
 122     return ((int32_t)(b - a) < 0);
 123 }
 124
 125 static uint32_t hpet_time_after64(uint64_t a, uint64_t b)
 126 {
 127     return ((int64_t)(b - a) < 0);
 128 }
 129
 130 static uint64_t ticks_to_ns(uint64_t value)
 131 {
 132     return value * HPET_CLK_PERIOD;
 133 }
 134
 135 static uint64_t ns_to_ticks(uint64_t value)
 136 {
 137     return value / HPET_CLK_PERIOD;
 138 }
 139
 140 static uint64_t hpet_fixup_reg(uint64_t new, uint64_t old, uint64_t mask)
 141 {
 142     new &= mask;
 143     new |= old & ~mask;
 144     return new;
 145 }
 146
 147 static int activating_bit(uint64_t old, uint64_t new, uint64_t mask)
 148 {
 149     return (!(old & mask) && (new & mask));
 150 }
 151
 152 static int deactivating_bit(uint64_t old, uint64_t new, uint64_t mask)
 153 {
 154     return ((old & mask) && !(new & mask));
 155 }
 156
 157 static uint64_t hpet_get_ticks(HPETState *s)
 158 {
 159     return ns_to_ticks(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + s->hpet_offset);
 160 }
 161
 162 /*
 163  * calculate diff between comparator value and current ticks
 164  */
 165 static inline uint64_t hpet_calculate_diff(HPETTimer *t, uint64_t current)
 166 {
 167
 168     if (t->config & HPET_TN_32BIT) {
 169         uint32_t diff, cmp;
 170
 171         cmp = (uint32_t)t->cmp;
 172         diff = cmp - (uint32_t)current;
 173         diff = (int32_t)diff > 0 ? diff : (uint32_t)1;
 174         return (uint64_t)diff;
 175     } else {
 176         uint64_t diff, cmp;
 177
 178         cmp = t->cmp;
 179         diff = cmp - current;
 180         diff = (int64_t)diff > 0 ? diff : (uint64_t)1;
 181         return diff;
 182     }
 183 }
 184
 185 static void update_irq(struct HPETTimer *timer, int set)
 186 {
 187     uint64_t mask;
 188     HPETState *s;
 189     int route;
 190
 191     if (timer->tn <= 1 && hpet_in_legacy_mode(timer->state)) {
 192         /* if LegacyReplacementRoute bit is set, HPET specification requires
 193          * timer0 be routed to IRQ0 in NON-APIC or IRQ2 in the I/O APIC,
 194          * timer1 be routed to IRQ8 in NON-APIC or IRQ8 in the I/O APIC.
 195          */
 196         route = (timer->tn == 0) ? 0 : RTC_ISA_IRQ;
 197     } else {
 198         route = timer_int_route(timer);
 199     }
 200     s = timer->state;
 201     mask = 1 << timer->tn;
 202     if (!set || !timer_enabled(timer) || !hpet_enabled(timer->state)) {
 203         s->isr &= ~mask;
 204         if (!timer_fsb_route(timer)) {
 205             qemu_irq_lower(s->irqs[route]);
 206         }
 207     } else if (timer_fsb_route(timer)) {
 208         address_space_stl_le(&address_space_memory, timer->fsb >> 32,
 209                              timer->fsb & 0xffffffff, MEMTXATTRS_UNSPECIFIED,
 210                              NULL);
 211     } else if (timer->config & HPET_TN_TYPE_LEVEL) {
 212         s->isr |= mask;
 213         qemu_irq_raise(s->irqs[route]);
 214     } else {
 215         s->isr &= ~mask;
 216         qemu_irq_pulse(s->irqs[route]);
 217     }
 218 }
 219
 220 static int hpet_pre_save(void *opaque)
 221 {
 222     HPETState *s = opaque;
 223
 224     /* save current counter value */
 225     if (hpet_enabled(s)) {
 226         s->hpet_counter = hpet_get_ticks(s);
 227     }
 228
 229     return 0;
 230 }
 231
 232 static int hpet_pre_load(void *opaque)
 233 {
 234     HPETState *s = opaque;
 235
 236     /* version 1 only supports 3, later versions will load the actual value */
 237     s->num_timers = HPET_MIN_TIMERS;
 238     return 0;
 239 }
 240
 241 static bool hpet_validate_num_timers(void *opaque, int version_id)
 242 {
 243     HPETState *s = opaque;
 244
 245     if (s->num_timers < HPET_MIN_TIMERS) {
 246         return false;
 247     } else if (s->num_timers > HPET_MAX_TIMERS) {
 248         return false;
 249     }
 250     return true;
 251 }
 252
 253 static int hpet_post_load(void *opaque, int version_id)
 254 {
 255     HPETState *s = opaque;
 256
 257     /* Recalculate the offset between the main counter and guest time */
 258     if (!s->hpet_offset_saved) {
 259         s->hpet_offset = ticks_to_ns(s->hpet_counter)
 260                         - qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
 261     }
 262
 263     /* Push number of timers into capability returned via HPET_ID */
 264     s->capability &= ~HPET_ID_NUM_TIM_MASK;
 265     s->capability |= (s->num_timers - 1) << HPET_ID_NUM_TIM_SHIFT;
 266     hpet_cfg.hpet[s->hpet_id].event_timer_block_id = (uint32_t)s->capability;
 267
 268     /* Derive HPET_MSI_SUPPORT from the capability of the first timer. */
 269     s->flags &= ~(1 << HPET_MSI_SUPPORT);
 270     if (s->timer[0].config & HPET_TN_FSB_CAP) {
 271         s->flags |= 1 << HPET_MSI_SUPPORT;
 272     }
 273     return 0;
 274 }
 275
 276 static bool hpet_offset_needed(void *opaque)
 277 {
 278     HPETState *s = opaque;
 279
 280     return hpet_enabled(s) && s->hpet_offset_saved;
 281 }
 282
 283 static bool hpet_rtc_irq_level_needed(void *opaque)
 284 {
 285     HPETState *s = opaque;
 286
 287     return s->rtc_irq_level != 0;
 288 }
 289
 290 static const VMStateDescription vmstate_hpet_rtc_irq_level = {
 291     .name = "hpet/rtc_irq_level",
 292     .version_id = 1,
 293     .minimum_version_id = 1,
 294     .needed = hpet_rtc_irq_level_needed,
 295     .fields = (VMStateField[]) {
 296         VMSTATE_UINT8(rtc_irq_level, HPETState),
 297         VMSTATE_END_OF_LIST()
 298     }
 299 };
 300
 301 static const VMStateDescription vmstate_hpet_offset = {
 302     .name = "hpet/offset",
 303     .version_id = 1,
 304     .minimum_version_id = 1,
 305     .needed = hpet_offset_needed,
 306     .fields = (VMStateField[]) {
 307         VMSTATE_UINT64(hpet_offset, HPETState),
 308         VMSTATE_END_OF_LIST()
 309     }
 310 };
 311
 312 static const VMStateDescription vmstate_hpet_timer = {
 313     .name = "hpet_timer",
 314     .version_id = 1,
 315     .minimum_version_id = 1,
 316     .fields = (VMStateField[]) {
 317         VMSTATE_UINT8(tn, HPETTimer),
 318         VMSTATE_UINT64(config, HPETTimer),
 319         VMSTATE_UINT64(cmp, HPETTimer),
 320         VMSTATE_UINT64(fsb, HPETTimer),
 321         VMSTATE_UINT64(period, HPETTimer),
 322         VMSTATE_UINT8(wrap_flag, HPETTimer),
 323         VMSTATE_TIMER_PTR(qemu_timer, HPETTimer),
 324         VMSTATE_END_OF_LIST()
 325     }
 326 };
 327
 328 static const VMStateDescription vmstate_hpet = {
 329     .name = "hpet",
 330     .version_id = 2,
 331     .minimum_version_id = 1,
 332     .pre_save = hpet_pre_save,
 333     .pre_load = hpet_pre_load,
 334     .post_load = hpet_post_load,
 335     .fields = (VMStateField[]) {
 336         VMSTATE_UINT64(config, HPETState),
 337         VMSTATE_UINT64(isr, HPETState),
 338         VMSTATE_UINT64(hpet_counter, HPETState),
 339         VMSTATE_UINT8_V(num_timers, HPETState, 2),
 340         VMSTATE_VALIDATE("num_timers in range", hpet_validate_num_timers),
 341         VMSTATE_STRUCT_VARRAY_UINT8(timer, HPETState, num_timers, 0,
 342                                     vmstate_hpet_timer, HPETTimer),
 343         VMSTATE_END_OF_LIST()
 344     },
 345     .subsections = (const VMStateDescription*[]) {
 346         &vmstate_hpet_rtc_irq_level,
 347         &vmstate_hpet_offset,
 348         NULL
 349     }
 350 };
 351
 352 /*
 353  * timer expiration callback
 354  */
 355 static void hpet_timer(void *opaque)
 356 {
 357     HPETTimer *t = opaque;
 358     uint64_t diff;
 359
 360     uint64_t period = t->period;
 361     uint64_t cur_tick = hpet_get_ticks(t->state);
 362
 363     if (timer_is_periodic(t) && period != 0) {
 364         if (t->config & HPET_TN_32BIT) {
 365             while (hpet_time_after(cur_tick, t->cmp)) {
 366                 t->cmp = (uint32_t)(t->cmp + t->period);
 367             }
 368         } else {
 369             while (hpet_time_after64(cur_tick, t->cmp)) {
 370                 t->cmp += period;
 371             }
 372         }
 373         diff = hpet_calculate_diff(t, cur_tick);
 374         timer_mod(t->qemu_timer,
 375                        qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + (int64_t)ticks_to_ns(diff));
 376     } else if (t->config & HPET_TN_32BIT && !timer_is_periodic(t)) {
 377         if (t->wrap_flag) {
 378             diff = hpet_calculate_diff(t, cur_tick);
 379             timer_mod(t->qemu_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
 380                            (int64_t)ticks_to_ns(diff));
 381             t->wrap_flag = 0;
 382         }
 383     }
 384     update_irq(t, 1);
 385 }
 386
 387 static void hpet_set_timer(HPETTimer *t)
 388 {
 389     uint64_t diff;
 390     uint32_t wrap_diff;  /* how many ticks until we wrap? */
 391     uint64_t cur_tick = hpet_get_ticks(t->state);
 392
 393     /* whenever new timer is being set up, make sure wrap_flag is 0 */
 394     t->wrap_flag = 0;
 395     diff = hpet_calculate_diff(t, cur_tick);
 396
 397     /* hpet spec says in one-shot 32-bit mode, generate an interrupt when
 398      * counter wraps in addition to an interrupt with comparator match.
 399      */
 400     if (t->config & HPET_TN_32BIT && !timer_is_periodic(t)) {
 401         wrap_diff = 0xffffffff - (uint32_t)cur_tick;
 402         if (wrap_diff < (uint32_t)diff) {
 403             diff = wrap_diff;
 404             t->wrap_flag = 1;
 405         }
 406     }
 407     timer_mod(t->qemu_timer,
 408                    qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + (int64_t)ticks_to_ns(diff));
 409 }
 410
 411 static void hpet_del_timer(HPETTimer *t)
 412 {
 413     timer_del(t->qemu_timer);
 414     update_irq(t, 0);
 415 }
 416
 417 #ifdef HPET_DEBUG
 418 static uint32_t hpet_ram_readb(void *opaque, hwaddr addr)
 419 {
 420     printf("qemu: hpet_read b at %" PRIx64 "\n", addr);
 421     return 0;
 422 }
 423
 424 static uint32_t hpet_ram_readw(void *opaque, hwaddr addr)
 425 {
 426     printf("qemu: hpet_read w at %" PRIx64 "\n", addr);
 427     return 0;
 428 }
 429 #endif
 430
 431 static uint64_t hpet_ram_read(void *opaque, hwaddr addr,
 432                               unsigned size)
 433 {
 434     HPETState *s = opaque;
 435     uint64_t cur_tick, index;
 436
 437     DPRINTF("qemu: Enter hpet_ram_readl at %" PRIx64 "\n", addr);
 438     index = addr;
 439     /*address range of all TN regs*/
 440     if (index >= 0x100 && index <= 0x3ff) {
 441         uint8_t timer_id = (addr - 0x100) / 0x20;
 442         HPETTimer *timer = &s->timer[timer_id];
 443
 444         if (timer_id > s->num_timers) {
 445             DPRINTF("qemu: timer id out of range\n");
 446             return 0;
 447         }
 448
 449         switch ((addr - 0x100) % 0x20) {
 450         case HPET_TN_CFG:
 451             return timer->config;
 452         case HPET_TN_CFG + 4: // Interrupt capabilities
 453             return timer->config >> 32;
 454         case HPET_TN_CMP: // comparator register
 455             return timer->cmp;
 456         case HPET_TN_CMP + 4:
 457             return timer->cmp >> 32;
 458         case HPET_TN_ROUTE:
 459             return timer->fsb;
 460         case HPET_TN_ROUTE + 4:
 461             return timer->fsb >> 32;
 462         default:
 463             DPRINTF("qemu: invalid hpet_ram_readl\n");
 464             break;
 465         }
 466     } else {
 467         switch (index) {
 468         case HPET_ID:
 469             return s->capability;
 470         case HPET_PERIOD:
 471             return s->capability >> 32;
 472         case HPET_CFG:
 473             return s->config;
 474         case HPET_CFG + 4:
 475             DPRINTF("qemu: invalid HPET_CFG + 4 hpet_ram_readl\n");
 476             return 0;
 477         case HPET_COUNTER:
 478             if (hpet_enabled(s)) {
 479                 cur_tick = hpet_get_ticks(s);
 480             } else {
 481                 cur_tick = s->hpet_counter;
 482             }
 483             DPRINTF("qemu: reading counter  = %" PRIx64 "\n", cur_tick);
 484             return cur_tick;
 485         case HPET_COUNTER + 4:
 486             if (hpet_enabled(s)) {
 487                 cur_tick = hpet_get_ticks(s);
 488             } else {
 489                 cur_tick = s->hpet_counter;
 490             }
 491             DPRINTF("qemu: reading counter + 4  = %" PRIx64 "\n", cur_tick);
 492             return cur_tick >> 32;
 493         case HPET_STATUS:
 494             return s->isr;
 495         default:
 496             DPRINTF("qemu: invalid hpet_ram_readl\n");
 497             break;
 498         }
 499     }
 500     return 0;
 501 }
 502
 503 static void hpet_ram_write(void *opaque, hwaddr addr,
 504                            uint64_t value, unsigned size)
 505 {
 506     int i;
 507     HPETState *s = opaque;
 508     uint64_t old_val, new_val, val, index;
 509
 510     DPRINTF("qemu: Enter hpet_ram_writel at %" PRIx64 " = %#x\n", addr, value);
 511     index = addr;
 512     old_val = hpet_ram_read(opaque, addr, 4);
 513     new_val = value;
 514
 515     /*address range of all TN regs*/
 516     if (index >= 0x100 && index <= 0x3ff) {
 517         uint8_t timer_id = (addr - 0x100) / 0x20;
 518         HPETTimer *timer = &s->timer[timer_id];
 519
 520         DPRINTF("qemu: hpet_ram_writel timer_id = %#x\n", timer_id);
 521         if (timer_id > s->num_timers) {
 522             DPRINTF("qemu: timer id out of range\n");
 523             return;
 524         }
 525         switch ((addr - 0x100) % 0x20) {
 526         case HPET_TN_CFG:
 527             DPRINTF("qemu: hpet_ram_writel HPET_TN_CFG\n");
 528             if (activating_bit(old_val, new_val, HPET_TN_FSB_ENABLE)) {
 529                 update_irq(timer, 0);
 530             }
 531             val = hpet_fixup_reg(new_val, old_val, HPET_TN_CFG_WRITE_MASK);
 532             timer->config = (timer->config & 0xffffffff00000000ULL) | val;
 533             if (new_val & HPET_TN_32BIT) {
 534                 timer->cmp = (uint32_t)timer->cmp;
 535                 timer->period = (uint32_t)timer->period;
 536             }
 537             if (activating_bit(old_val, new_val, HPET_TN_ENABLE) &&
 538                 hpet_enabled(s)) {
 539                 hpet_set_timer(timer);
 540             } else if (deactivating_bit(old_val, new_val, HPET_TN_ENABLE)) {
 541                 hpet_del_timer(timer);
 542             }
 543             break;
 544         case HPET_TN_CFG + 4: // Interrupt capabilities
 545             DPRINTF("qemu: invalid HPET_TN_CFG+4 write\n");
 546             break;
 547         case HPET_TN_CMP: // comparator register
 548             DPRINTF("qemu: hpet_ram_writel HPET_TN_CMP\n");
 549             if (timer->config & HPET_TN_32BIT) {
 550                 new_val = (uint32_t)new_val;
 551             }
 552             if (!timer_is_periodic(timer)
 553                 || (timer->config & HPET_TN_SETVAL)) {
 554                 timer->cmp = (timer->cmp & 0xffffffff00000000ULL) | new_val;
 555             }
 556             if (timer_is_periodic(timer)) {
 557                 /*
 558                  * FIXME: Clamp period to reasonable min value?
 559                  * Clamp period to reasonable max value
 560                  */
 561                 new_val &= (timer->config & HPET_TN_32BIT ? ~0u : ~0ull) >> 1;
 562                 timer->period =
 563                     (timer->period & 0xffffffff00000000ULL) | new_val;
 564             }
 565             timer->config &= ~HPET_TN_SETVAL;
 566             if (hpet_enabled(s)) {
 567                 hpet_set_timer(timer);
 568             }
 569             break;
 570         case HPET_TN_CMP + 4: // comparator register high order
 571             DPRINTF("qemu: hpet_ram_writel HPET_TN_CMP + 4\n");
 572             if (!timer_is_periodic(timer)
 573                 || (timer->config & HPET_TN_SETVAL)) {
 574                 timer->cmp = (timer->cmp & 0xffffffffULL) | new_val << 32;
 575             } else {
 576                 /*
 577                  * FIXME: Clamp period to reasonable min value?
 578                  * Clamp period to reasonable max value
 579                  */
 580                 new_val &= (timer->config & HPET_TN_32BIT ? ~0u : ~0ull) >> 1;
 581                 timer->period =
 582                     (timer->period & 0xffffffffULL) | new_val << 32;
 583                 }
 584                 timer->config &= ~HPET_TN_SETVAL;
 585                 if (hpet_enabled(s)) {
 586                     hpet_set_timer(timer);
 587                 }
 588                 break;
 589         case HPET_TN_ROUTE:
 590             timer->fsb = (timer->fsb & 0xffffffff00000000ULL) | new_val;
 591             break;
 592         case HPET_TN_ROUTE + 4:
 593             timer->fsb = (new_val << 32) | (timer->fsb & 0xffffffff);
 594             break;
 595         default:
 596             DPRINTF("qemu: invalid hpet_ram_writel\n");
 597             break;
 598         }
 599         return;
 600     } else {
 601         switch (index) {
 602         case HPET_ID:
 603             return;
 604         case HPET_CFG:
 605             val = hpet_fixup_reg(new_val, old_val, HPET_CFG_WRITE_MASK);
 606             s->config = (s->config & 0xffffffff00000000ULL) | val;
 607             if (activating_bit(old_val, new_val, HPET_CFG_ENABLE)) {
 608                 /* Enable main counter and interrupt generation. */
 609                 s->hpet_offset =
 610                     ticks_to_ns(s->hpet_counter) - qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
 611                 for (i = 0; i < s->num_timers; i++) {
 612                     if ((&s->timer[i])->cmp != ~0ULL) {
 613                         hpet_set_timer(&s->timer[i]);
 614                     }
 615                 }
 616             } else if (deactivating_bit(old_val, new_val, HPET_CFG_ENABLE)) {
 617                 /* Halt main counter and disable interrupt generation. */
 618                 s->hpet_counter = hpet_get_ticks(s);
 619                 for (i = 0; i < s->num_timers; i++) {
 620                     hpet_del_timer(&s->timer[i]);
 621                 }
 622             }
 623             /* i8254 and RTC output pins are disabled
 624              * when HPET is in legacy mode */
 625             if (activating_bit(old_val, new_val, HPET_CFG_LEGACY)) {
 626                 qemu_set_irq(s->pit_enabled, 0);
 627                 qemu_irq_lower(s->irqs[0]);
 628                 qemu_irq_lower(s->irqs[RTC_ISA_IRQ]);
 629             } else if (deactivating_bit(old_val, new_val, HPET_CFG_LEGACY)) {
 630                 qemu_irq_lower(s->irqs[0]);
 631                 qemu_set_irq(s->pit_enabled, 1);
 632                 qemu_set_irq(s->irqs[RTC_ISA_IRQ], s->rtc_irq_level);
 633             }
 634             break;
 635         case HPET_CFG + 4:
 636             DPRINTF("qemu: invalid HPET_CFG+4 write\n");
 637             break;
 638         case HPET_STATUS:
 639             val = new_val & s->isr;
 640             for (i = 0; i < s->num_timers; i++) {
 641                 if (val & (1 << i)) {
 642                     update_irq(&s->timer[i], 0);
 643                 }
 644             }
 645             break;
 646         case HPET_COUNTER:
 647             if (hpet_enabled(s)) {
 648                 DPRINTF("qemu: Writing counter while HPET enabled!\n");
 649             }
 650             s->hpet_counter =
 651                 (s->hpet_counter & 0xffffffff00000000ULL) | value;
 652             DPRINTF("qemu: HPET counter written. ctr = %#x -> %" PRIx64 "\n",
 653                     value, s->hpet_counter);
 654             break;
 655         case HPET_COUNTER + 4:
 656             if (hpet_enabled(s)) {
 657                 DPRINTF("qemu: Writing counter while HPET enabled!\n");
 658             }
 659             s->hpet_counter =
 660                 (s->hpet_counter & 0xffffffffULL) | (((uint64_t)value) << 32);
 661             DPRINTF("qemu: HPET counter + 4 written. ctr = %#x -> %" PRIx64 "\n",
 662                     value, s->hpet_counter);
 663             break;
 664         default:
 665             DPRINTF("qemu: invalid hpet_ram_writel\n");
 666             break;
 667         }
 668     }
 669 }
 670
 671 static const MemoryRegionOps hpet_ram_ops = {
 672     .read = hpet_ram_read,
 673     .write = hpet_ram_write,
 674     .valid = {
 675         .min_access_size = 4,
 676         .max_access_size = 4,
 677     },
 678     .endianness = DEVICE_NATIVE_ENDIAN,
 679 };
 680
 681 static void hpet_reset(DeviceState *d)
 682 {
 683     HPETState *s = HPET(d);
 684     SysBusDevice *sbd = SYS_BUS_DEVICE(d);
 685     int i;
 686
 687     for (i = 0; i < s->num_timers; i++) {
 688         HPETTimer *timer = &s->timer[i];
 689
 690         hpet_del_timer(timer);
 691         timer->cmp = ~0ULL;
 692         timer->config = HPET_TN_PERIODIC_CAP | HPET_TN_SIZE_CAP;
 693         if (s->flags & (1 << HPET_MSI_SUPPORT)) {
 694             timer->config |= HPET_TN_FSB_CAP;
 695         }
 696         /* advertise availability of ioapic int */
 697         timer->config |=  (uint64_t)s->intcap << 32;
 698         timer->period = 0ULL;
 699         timer->wrap_flag = 0;
 700     }
 701
 702     qemu_set_irq(s->pit_enabled, 1);
 703     s->hpet_counter = 0ULL;
 704     s->hpet_offset = 0ULL;
 705     s->config = 0ULL;
 706     hpet_cfg.hpet[s->hpet_id].event_timer_block_id = (uint32_t)s->capability;
 707     hpet_cfg.hpet[s->hpet_id].address = sbd->mmio[0].addr;
 708
 709     /* to document that the RTC lowers its output on reset as well */
 710     s->rtc_irq_level = 0;
 711 }
 712
 713 static void hpet_handle_legacy_irq(void *opaque, int n, int level)
 714 {
 715     HPETState *s = HPET(opaque);
 716
 717     if (n == HPET_LEGACY_PIT_INT) {
 718         if (!hpet_in_legacy_mode(s)) {
 719             qemu_set_irq(s->irqs[0], level);
 720         }
 721     } else {
 722         s->rtc_irq_level = level;
 723         if (!hpet_in_legacy_mode(s)) {
 724             qemu_set_irq(s->irqs[RTC_ISA_IRQ], level);
 725         }
 726     }
 727 }
 728
 729 static void hpet_init(Object *obj)
 730 {
 731     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
 732     HPETState *s = HPET(obj);
 733
 734     /* HPET Area */
 735     memory_region_init_io(&s->iomem, obj, &hpet_ram_ops, s, "hpet", HPET_LEN);
 736     sysbus_init_mmio(sbd, &s->iomem);
 737 }
 738
 739 static void hpet_realize(DeviceState *dev, Error **errp)
 740 {
 741     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
 742     HPETState *s = HPET(dev);
 743     int i;
 744     HPETTimer *timer;
 745
 746     if (!s->intcap) {
 747         error_printf("Hpet's intcap not initialized.\n");
 748     }
 749     if (hpet_cfg.count == UINT8_MAX) {
 750         /* first instance */
 751         hpet_cfg.count = 0;
 752     }
 753
 754     if (hpet_cfg.count == 8) {
 755         error_setg(errp, "Only 8 instances of HPET is allowed");
 756         return;
 757     }
 758
 759     s->hpet_id = hpet_cfg.count++;
 760
 761     for (i = 0; i < HPET_NUM_IRQ_ROUTES; i++) {
 762         sysbus_init_irq(sbd, &s->irqs[i]);
 763     }
 764
 765     if (s->num_timers < HPET_MIN_TIMERS) {
 766         s->num_timers = HPET_MIN_TIMERS;
 767     } else if (s->num_timers > HPET_MAX_TIMERS) {
 768         s->num_timers = HPET_MAX_TIMERS;
 769     }
 770     for (i = 0; i < HPET_MAX_TIMERS; i++) {
 771         timer = &s->timer[i];
 772         timer->qemu_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, hpet_timer, timer);
 773         timer->tn = i;
 774         timer->state = s;
 775     }
 776
 777     /* 64-bit main counter; LegacyReplacementRoute. */
 778     s->capability = 0x8086a001ULL;
 779     s->capability |= (s->num_timers - 1) << HPET_ID_NUM_TIM_SHIFT;
 780     s->capability |= ((uint64_t)(HPET_CLK_PERIOD * FS_PER_NS) << 32);
 781
 782     qdev_init_gpio_in(dev, hpet_handle_legacy_irq, 2);
 783     qdev_init_gpio_out(dev, &s->pit_enabled, 1);
 784 }
 785
 786 static Property hpet_device_properties[] = {
 787     DEFINE_PROP_UINT8("timers", HPETState, num_timers, HPET_MIN_TIMERS),
 788     DEFINE_PROP_BIT("msi", HPETState, flags, HPET_MSI_SUPPORT, false),
 789     DEFINE_PROP_UINT32(HPET_INTCAP, HPETState, intcap, 0),
 790     DEFINE_PROP_BOOL("hpet-offset-saved", HPETState, hpet_offset_saved, true),
 791     DEFINE_PROP_END_OF_LIST(),
 792 };
 793
 794 static void hpet_device_class_init(ObjectClass *klass, void *data)
 795 {
 796     DeviceClass *dc = DEVICE_CLASS(klass);
 797
 798     dc->realize = hpet_realize;
 799     dc->reset = hpet_reset;
 800     dc->vmsd = &vmstate_hpet;
 801     dc->props = hpet_device_properties;
 802 }
 803
 804 static const TypeInfo hpet_device_info = {
 805     .name          = TYPE_HPET,
 806     .parent        = TYPE_SYS_BUS_DEVICE,
 807     .instance_size = sizeof(HPETState),
 808     .instance_init = hpet_init,
 809     .class_init    = hpet_device_class_init,
 810 };
 811
 812 static void hpet_register_types(void)
 813 {
 814     type_register_static(&hpet_device_info);
 815 }
 816
 817 type_init(hpet_register_types)