hw/hpet.c

   1 /*
   2  *  High Precisition 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 "hw.h"
  28 #include "pc.h"
  29 #include "console.h"
  30 #include "qemu-timer.h"
  31 #include "hpet_emul.h"
  32 #include "sysbus.h"
  33 #include "mc146818rtc.h"
  34
  35 //#define HPET_DEBUG
  36 #ifdef HPET_DEBUG
  37 #define DPRINTF printf
  38 #else
  39 #define DPRINTF(...)
  40 #endif
  41
  42 #define HPET_MSI_SUPPORT        0
  43
  44 struct HPETState;
  45 typedef struct HPETTimer {  /* timers */
  46     uint8_t tn;             /*timer number*/
  47     QEMUTimer *qemu_timer;
  48     struct HPETState *state;
  49     /* Memory-mapped, software visible timer registers */
  50     uint64_t config;        /* configuration/cap */
  51     uint64_t cmp;           /* comparator */
  52     uint64_t fsb;           /* FSB route */
  53     /* Hidden register state */
  54     uint64_t period;        /* Last value written to comparator */
  55     uint8_t wrap_flag;      /* timer pop will indicate wrap for one-shot 32-bit
  56                              * mode. Next pop will be actual timer expiration.
  57                              */
  58 } HPETTimer;
  59
  60 typedef struct HPETState {
  61     SysBusDevice busdev;
  62     MemoryRegion iomem;
  63     uint64_t hpet_offset;
  64     qemu_irq irqs[HPET_NUM_IRQ_ROUTES];
  65     uint32_t flags;
  66     uint8_t rtc_irq_level;
  67     uint8_t num_timers;
  68     HPETTimer timer[HPET_MAX_TIMERS];
  69
  70     /* Memory-mapped, software visible registers */
  71     uint64_t capability;        /* capabilities */
  72     uint64_t config;            /* configuration */
  73     uint64_t isr;               /* interrupt status reg */
  74     uint64_t hpet_counter;      /* main counter */
  75     uint8_t  hpet_id;           /* instance id */
  76 } HPETState;
  77
  78 static uint32_t hpet_in_legacy_mode(HPETState *s)
  79 {
  80     return s->config & HPET_CFG_LEGACY;
  81 }
  82
  83 static uint32_t timer_int_route(struct HPETTimer *timer)
  84 {
  85     return (timer->config & HPET_TN_INT_ROUTE_MASK) >> HPET_TN_INT_ROUTE_SHIFT;
  86 }
  87
  88 static uint32_t timer_fsb_route(HPETTimer *t)
  89 {
  90     return t->config & HPET_TN_FSB_ENABLE;
  91 }
  92
  93 static uint32_t hpet_enabled(HPETState *s)
  94 {
  95     return s->config & HPET_CFG_ENABLE;
  96 }
  97
  98 static uint32_t timer_is_periodic(HPETTimer *t)
  99 {
 100     return t->config & HPET_TN_PERIODIC;
 101 }
 102
 103 static uint32_t timer_enabled(HPETTimer *t)
 104 {
 105     return t->config & HPET_TN_ENABLE;
 106 }
 107
 108 static uint32_t hpet_time_after(uint64_t a, uint64_t b)
 109 {
 110     return ((int32_t)(b) - (int32_t)(a) < 0);
 111 }
 112
 113 static uint32_t hpet_time_after64(uint64_t a, uint64_t b)
 114 {
 115     return ((int64_t)(b) - (int64_t)(a) < 0);
 116 }
 117
 118 static uint64_t ticks_to_ns(uint64_t value)
 119 {
 120     return (muldiv64(value, HPET_CLK_PERIOD, FS_PER_NS));
 121 }
 122
 123 static uint64_t ns_to_ticks(uint64_t value)
 124 {
 125     return (muldiv64(value, FS_PER_NS, HPET_CLK_PERIOD));
 126 }
 127
 128 static uint64_t hpet_fixup_reg(uint64_t new, uint64_t old, uint64_t mask)
 129 {
 130     new &= mask;
 131     new |= old & ~mask;
 132     return new;
 133 }
 134
 135 static int activating_bit(uint64_t old, uint64_t new, uint64_t mask)
 136 {
 137     return (!(old & mask) && (new & mask));
 138 }
 139
 140 static int deactivating_bit(uint64_t old, uint64_t new, uint64_t mask)
 141 {
 142     return ((old & mask) && !(new & mask));
 143 }
 144
 145 static uint64_t hpet_get_ticks(HPETState *s)
 146 {
 147     return ns_to_ticks(qemu_get_clock_ns(vm_clock) + s->hpet_offset);
 148 }
 149
 150 /*
 151  * calculate diff between comparator value and current ticks
 152  */
 153 static inline uint64_t hpet_calculate_diff(HPETTimer *t, uint64_t current)
 154 {
 155
 156     if (t->config & HPET_TN_32BIT) {
 157         uint32_t diff, cmp;
 158
 159         cmp = (uint32_t)t->cmp;
 160         diff = cmp - (uint32_t)current;
 161         diff = (int32_t)diff > 0 ? diff : (uint32_t)1;
 162         return (uint64_t)diff;
 163     } else {
 164         uint64_t diff, cmp;
 165
 166         cmp = t->cmp;
 167         diff = cmp - current;
 168         diff = (int64_t)diff > 0 ? diff : (uint64_t)1;
 169         return diff;
 170     }
 171 }
 172
 173 static void update_irq(struct HPETTimer *timer, int set)
 174 {
 175     uint64_t mask;
 176     HPETState *s;
 177     int route;
 178
 179     if (timer->tn <= 1 && hpet_in_legacy_mode(timer->state)) {
 180         /* if LegacyReplacementRoute bit is set, HPET specification requires
 181          * timer0 be routed to IRQ0 in NON-APIC or IRQ2 in the I/O APIC,
 182          * timer1 be routed to IRQ8 in NON-APIC or IRQ8 in the I/O APIC.
 183          */
 184         route = (timer->tn == 0) ? 0 : RTC_ISA_IRQ;
 185     } else {
 186         route = timer_int_route(timer);
 187     }
 188     s = timer->state;
 189     mask = 1 << timer->tn;
 190     if (!set || !timer_enabled(timer) || !hpet_enabled(timer->state)) {
 191         s->isr &= ~mask;
 192         if (!timer_fsb_route(timer)) {
 193             qemu_irq_lower(s->irqs[route]);
 194         }
 195     } else if (timer_fsb_route(timer)) {
 196         stl_le_phys(timer->fsb >> 32, timer->fsb & 0xffffffff);
 197     } else if (timer->config & HPET_TN_TYPE_LEVEL) {
 198         s->isr |= mask;
 199         qemu_irq_raise(s->irqs[route]);
 200     } else {
 201         s->isr &= ~mask;
 202         qemu_irq_pulse(s->irqs[route]);
 203     }
 204 }
 205
 206 static void hpet_pre_save(void *opaque)
 207 {
 208     HPETState *s = opaque;
 209
 210     /* save current counter value */
 211     s->hpet_counter = hpet_get_ticks(s);
 212 }
 213
 214 static int hpet_pre_load(void *opaque)
 215 {
 216     HPETState *s = opaque;
 217
 218     /* version 1 only supports 3, later versions will load the actual value */
 219     s->num_timers = HPET_MIN_TIMERS;
 220     return 0;
 221 }
 222
 223 static int hpet_post_load(void *opaque, int version_id)
 224 {
 225     HPETState *s = opaque;
 226
 227     /* Recalculate the offset between the main counter and guest time */
 228     s->hpet_offset = ticks_to_ns(s->hpet_counter) - qemu_get_clock_ns(vm_clock);
 229
 230     /* Push number of timers into capability returned via HPET_ID */
 231     s->capability &= ~HPET_ID_NUM_TIM_MASK;
 232     s->capability |= (s->num_timers - 1) << HPET_ID_NUM_TIM_SHIFT;
 233     hpet_cfg.hpet[s->hpet_id].event_timer_block_id = (uint32_t)s->capability;
 234
 235     /* Derive HPET_MSI_SUPPORT from the capability of the first timer. */
 236     s->flags &= ~(1 << HPET_MSI_SUPPORT);
 237     if (s->timer[0].config & HPET_TN_FSB_CAP) {
 238         s->flags |= 1 << HPET_MSI_SUPPORT;
 239     }
 240     return 0;
 241 }
 242
 243 static const VMStateDescription vmstate_hpet_timer = {
 244     .name = "hpet_timer",
 245     .version_id = 1,
 246     .minimum_version_id = 1,
 247     .minimum_version_id_old = 1,
 248     .fields      = (VMStateField []) {
 249         VMSTATE_UINT8(tn, HPETTimer),
 250         VMSTATE_UINT64(config, HPETTimer),
 251         VMSTATE_UINT64(cmp, HPETTimer),
 252         VMSTATE_UINT64(fsb, HPETTimer),
 253         VMSTATE_UINT64(period, HPETTimer),
 254         VMSTATE_UINT8(wrap_flag, HPETTimer),
 255         VMSTATE_TIMER(qemu_timer, HPETTimer),
 256         VMSTATE_END_OF_LIST()
 257     }
 258 };
 259
 260 static const VMStateDescription vmstate_hpet = {
 261     .name = "hpet",
 262     .version_id = 2,
 263     .minimum_version_id = 1,
 264     .minimum_version_id_old = 1,
 265     .pre_save = hpet_pre_save,
 266     .pre_load = hpet_pre_load,
 267     .post_load = hpet_post_load,
 268     .fields      = (VMStateField []) {
 269         VMSTATE_UINT64(config, HPETState),
 270         VMSTATE_UINT64(isr, HPETState),
 271         VMSTATE_UINT64(hpet_counter, HPETState),
 272         VMSTATE_UINT8_V(num_timers, HPETState, 2),
 273         VMSTATE_STRUCT_VARRAY_UINT8(timer, HPETState, num_timers, 0,
 274                                     vmstate_hpet_timer, HPETTimer),
 275         VMSTATE_END_OF_LIST()
 276     }
 277 };
 278
 279 /*
 280  * timer expiration callback
 281  */
 282 static void hpet_timer(void *opaque)
 283 {
 284     HPETTimer *t = opaque;
 285     uint64_t diff;
 286
 287     uint64_t period = t->period;
 288     uint64_t cur_tick = hpet_get_ticks(t->state);
 289
 290     if (timer_is_periodic(t) && period != 0) {
 291         if (t->config & HPET_TN_32BIT) {
 292             while (hpet_time_after(cur_tick, t->cmp)) {
 293                 t->cmp = (uint32_t)(t->cmp + t->period);
 294             }
 295         } else {
 296             while (hpet_time_after64(cur_tick, t->cmp)) {
 297                 t->cmp += period;
 298             }
 299         }
 300         diff = hpet_calculate_diff(t, cur_tick);
 301         qemu_mod_timer(t->qemu_timer,
 302                        qemu_get_clock_ns(vm_clock) + (int64_t)ticks_to_ns(diff));
 303     } else if (t->config & HPET_TN_32BIT && !timer_is_periodic(t)) {
 304         if (t->wrap_flag) {
 305             diff = hpet_calculate_diff(t, cur_tick);
 306             qemu_mod_timer(t->qemu_timer, qemu_get_clock_ns(vm_clock) +
 307                            (int64_t)ticks_to_ns(diff));
 308             t->wrap_flag = 0;
 309         }
 310     }
 311     update_irq(t, 1);
 312 }
 313
 314 static void hpet_set_timer(HPETTimer *t)
 315 {
 316     uint64_t diff;
 317     uint32_t wrap_diff;  /* how many ticks until we wrap? */
 318     uint64_t cur_tick = hpet_get_ticks(t->state);
 319
 320     /* whenever new timer is being set up, make sure wrap_flag is 0 */
 321     t->wrap_flag = 0;
 322     diff = hpet_calculate_diff(t, cur_tick);
 323
 324     /* hpet spec says in one-shot 32-bit mode, generate an interrupt when
 325      * counter wraps in addition to an interrupt with comparator match.
 326      */
 327     if (t->config & HPET_TN_32BIT && !timer_is_periodic(t)) {
 328         wrap_diff = 0xffffffff - (uint32_t)cur_tick;
 329         if (wrap_diff < (uint32_t)diff) {
 330             diff = wrap_diff;
 331             t->wrap_flag = 1;
 332         }
 333     }
 334     qemu_mod_timer(t->qemu_timer,
 335                    qemu_get_clock_ns(vm_clock) + (int64_t)ticks_to_ns(diff));
 336 }
 337
 338 static void hpet_del_timer(HPETTimer *t)
 339 {
 340     qemu_del_timer(t->qemu_timer);
 341     update_irq(t, 0);
 342 }
 343
 344 #ifdef HPET_DEBUG
 345 static uint32_t hpet_ram_readb(void *opaque, target_phys_addr_t addr)
 346 {
 347     printf("qemu: hpet_read b at %" PRIx64 "\n", addr);
 348     return 0;
 349 }
 350
 351 static uint32_t hpet_ram_readw(void *opaque, target_phys_addr_t addr)
 352 {
 353     printf("qemu: hpet_read w at %" PRIx64 "\n", addr);
 354     return 0;
 355 }
 356 #endif
 357
 358 static uint64_t hpet_ram_read(void *opaque, target_phys_addr_t addr,
 359                               unsigned size)
 360 {
 361     HPETState *s = opaque;
 362     uint64_t cur_tick, index;
 363
 364     DPRINTF("qemu: Enter hpet_ram_readl at %" PRIx64 "\n", addr);
 365     index = addr;
 366     /*address range of all TN regs*/
 367     if (index >= 0x100 && index <= 0x3ff) {
 368         uint8_t timer_id = (addr - 0x100) / 0x20;
 369         HPETTimer *timer = &s->timer[timer_id];
 370
 371         if (timer_id > s->num_timers) {
 372             DPRINTF("qemu: timer id out of range\n");
 373             return 0;
 374         }
 375
 376         switch ((addr - 0x100) % 0x20) {
 377         case HPET_TN_CFG:
 378             return timer->config;
 379         case HPET_TN_CFG + 4: // Interrupt capabilities
 380             return timer->config >> 32;
 381         case HPET_TN_CMP: // comparator register
 382             return timer->cmp;
 383         case HPET_TN_CMP + 4:
 384             return timer->cmp >> 32;
 385         case HPET_TN_ROUTE:
 386             return timer->fsb;
 387         case HPET_TN_ROUTE + 4:
 388             return timer->fsb >> 32;
 389         default:
 390             DPRINTF("qemu: invalid hpet_ram_readl\n");
 391             break;
 392         }
 393     } else {
 394         switch (index) {
 395         case HPET_ID:
 396             return s->capability;
 397         case HPET_PERIOD:
 398             return s->capability >> 32;
 399         case HPET_CFG:
 400             return s->config;
 401         case HPET_CFG + 4:
 402             DPRINTF("qemu: invalid HPET_CFG + 4 hpet_ram_readl\n");
 403             return 0;
 404         case HPET_COUNTER:
 405             if (hpet_enabled(s)) {
 406                 cur_tick = hpet_get_ticks(s);
 407             } else {
 408                 cur_tick = s->hpet_counter;
 409             }
 410             DPRINTF("qemu: reading counter  = %" PRIx64 "\n", cur_tick);
 411             return cur_tick;
 412         case HPET_COUNTER + 4:
 413             if (hpet_enabled(s)) {
 414                 cur_tick = hpet_get_ticks(s);
 415             } else {
 416                 cur_tick = s->hpet_counter;
 417             }
 418             DPRINTF("qemu: reading counter + 4  = %" PRIx64 "\n", cur_tick);
 419             return cur_tick >> 32;
 420         case HPET_STATUS:
 421             return s->isr;
 422         default:
 423             DPRINTF("qemu: invalid hpet_ram_readl\n");
 424             break;
 425         }
 426     }
 427     return 0;
 428 }
 429
 430 static void hpet_ram_write(void *opaque, target_phys_addr_t addr,
 431                            uint64_t value, unsigned size)
 432 {
 433     int i;
 434     HPETState *s = opaque;
 435     uint64_t old_val, new_val, val, index;
 436
 437     DPRINTF("qemu: Enter hpet_ram_writel at %" PRIx64 " = %#x\n", addr, value);
 438     index = addr;
 439     old_val = hpet_ram_read(opaque, addr, 4);
 440     new_val = value;
 441
 442     /*address range of all TN regs*/
 443     if (index >= 0x100 && index <= 0x3ff) {
 444         uint8_t timer_id = (addr - 0x100) / 0x20;
 445         HPETTimer *timer = &s->timer[timer_id];
 446
 447         DPRINTF("qemu: hpet_ram_writel timer_id = %#x\n", timer_id);
 448         if (timer_id > s->num_timers) {
 449             DPRINTF("qemu: timer id out of range\n");
 450             return;
 451         }
 452         switch ((addr - 0x100) % 0x20) {
 453         case HPET_TN_CFG:
 454             DPRINTF("qemu: hpet_ram_writel HPET_TN_CFG\n");
 455             if (activating_bit(old_val, new_val, HPET_TN_FSB_ENABLE)) {
 456                 update_irq(timer, 0);
 457             }
 458             val = hpet_fixup_reg(new_val, old_val, HPET_TN_CFG_WRITE_MASK);
 459             timer->config = (timer->config & 0xffffffff00000000ULL) | val;
 460             if (new_val & HPET_TN_32BIT) {
 461                 timer->cmp = (uint32_t)timer->cmp;
 462                 timer->period = (uint32_t)timer->period;
 463             }
 464             if (activating_bit(old_val, new_val, HPET_TN_ENABLE)) {
 465                 hpet_set_timer(timer);
 466             } else if (deactivating_bit(old_val, new_val, HPET_TN_ENABLE)) {
 467                 hpet_del_timer(timer);
 468             }
 469             break;
 470         case HPET_TN_CFG + 4: // Interrupt capabilities
 471             DPRINTF("qemu: invalid HPET_TN_CFG+4 write\n");
 472             break;
 473         case HPET_TN_CMP: // comparator register
 474             DPRINTF("qemu: hpet_ram_writel HPET_TN_CMP\n");
 475             if (timer->config & HPET_TN_32BIT) {
 476                 new_val = (uint32_t)new_val;
 477             }
 478             if (!timer_is_periodic(timer)
 479                 || (timer->config & HPET_TN_SETVAL)) {
 480                 timer->cmp = (timer->cmp & 0xffffffff00000000ULL) | new_val;
 481             }
 482             if (timer_is_periodic(timer)) {
 483                 /*
 484                  * FIXME: Clamp period to reasonable min value?
 485                  * Clamp period to reasonable max value
 486                  */
 487                 new_val &= (timer->config & HPET_TN_32BIT ? ~0u : ~0ull) >> 1;
 488                 timer->period =
 489                     (timer->period & 0xffffffff00000000ULL) | new_val;
 490             }
 491             timer->config &= ~HPET_TN_SETVAL;
 492             if (hpet_enabled(s)) {
 493                 hpet_set_timer(timer);
 494             }
 495             break;
 496         case HPET_TN_CMP + 4: // comparator register high order
 497             DPRINTF("qemu: hpet_ram_writel HPET_TN_CMP + 4\n");
 498             if (!timer_is_periodic(timer)
 499                 || (timer->config & HPET_TN_SETVAL)) {
 500                 timer->cmp = (timer->cmp & 0xffffffffULL) | new_val << 32;
 501             } else {
 502                 /*
 503                  * FIXME: Clamp period to reasonable min value?
 504                  * Clamp period to reasonable max value
 505                  */
 506                 new_val &= (timer->config & HPET_TN_32BIT ? ~0u : ~0ull) >> 1;
 507                 timer->period =
 508                     (timer->period & 0xffffffffULL) | new_val << 32;
 509                 }
 510                 timer->config &= ~HPET_TN_SETVAL;
 511                 if (hpet_enabled(s)) {
 512                     hpet_set_timer(timer);
 513                 }
 514                 break;
 515         case HPET_TN_ROUTE:
 516             timer->fsb = (timer->fsb & 0xffffffff00000000ULL) | new_val;
 517             break;
 518         case HPET_TN_ROUTE + 4:
 519             timer->fsb = (new_val << 32) | (timer->fsb & 0xffffffff);
 520             break;
 521         default:
 522             DPRINTF("qemu: invalid hpet_ram_writel\n");
 523             break;
 524         }
 525         return;
 526     } else {
 527         switch (index) {
 528         case HPET_ID:
 529             return;
 530         case HPET_CFG:
 531             val = hpet_fixup_reg(new_val, old_val, HPET_CFG_WRITE_MASK);
 532             s->config = (s->config & 0xffffffff00000000ULL) | val;
 533             if (activating_bit(old_val, new_val, HPET_CFG_ENABLE)) {
 534                 /* Enable main counter and interrupt generation. */
 535                 s->hpet_offset =
 536                     ticks_to_ns(s->hpet_counter) - qemu_get_clock_ns(vm_clock);
 537                 for (i = 0; i < s->num_timers; i++) {
 538                     if ((&s->timer[i])->cmp != ~0ULL) {
 539                         hpet_set_timer(&s->timer[i]);
 540                     }
 541                 }
 542             } else if (deactivating_bit(old_val, new_val, HPET_CFG_ENABLE)) {
 543                 /* Halt main counter and disable interrupt generation. */
 544                 s->hpet_counter = hpet_get_ticks(s);
 545                 for (i = 0; i < s->num_timers; i++) {
 546                     hpet_del_timer(&s->timer[i]);
 547                 }
 548             }
 549             /* i8254 and RTC are disabled when HPET is in legacy mode */
 550             if (activating_bit(old_val, new_val, HPET_CFG_LEGACY)) {
 551                 hpet_pit_disable();
 552                 qemu_irq_lower(s->irqs[RTC_ISA_IRQ]);
 553             } else if (deactivating_bit(old_val, new_val, HPET_CFG_LEGACY)) {
 554                 hpet_pit_enable();
 555                 qemu_set_irq(s->irqs[RTC_ISA_IRQ], s->rtc_irq_level);
 556             }
 557             break;
 558         case HPET_CFG + 4:
 559             DPRINTF("qemu: invalid HPET_CFG+4 write\n");
 560             break;
 561         case HPET_STATUS:
 562             val = new_val & s->isr;
 563             for (i = 0; i < s->num_timers; i++) {
 564                 if (val & (1 << i)) {
 565                     update_irq(&s->timer[i], 0);
 566                 }
 567             }
 568             break;
 569         case HPET_COUNTER:
 570             if (hpet_enabled(s)) {
 571                 DPRINTF("qemu: Writing counter while HPET enabled!\n");
 572             }
 573             s->hpet_counter =
 574                 (s->hpet_counter & 0xffffffff00000000ULL) | value;
 575             DPRINTF("qemu: HPET counter written. ctr = %#x -> %" PRIx64 "\n",
 576                     value, s->hpet_counter);
 577             break;
 578         case HPET_COUNTER + 4:
 579             if (hpet_enabled(s)) {
 580                 DPRINTF("qemu: Writing counter while HPET enabled!\n");
 581             }
 582             s->hpet_counter =
 583                 (s->hpet_counter & 0xffffffffULL) | (((uint64_t)value) << 32);
 584             DPRINTF("qemu: HPET counter + 4 written. ctr = %#x -> %" PRIx64 "\n",
 585                     value, s->hpet_counter);
 586             break;
 587         default:
 588             DPRINTF("qemu: invalid hpet_ram_writel\n");
 589             break;
 590         }
 591     }
 592 }
 593
 594 static const MemoryRegionOps hpet_ram_ops = {
 595     .read = hpet_ram_read,
 596     .write = hpet_ram_write,
 597     .valid = {
 598         .min_access_size = 4,
 599         .max_access_size = 4,
 600     },
 601     .endianness = DEVICE_NATIVE_ENDIAN,
 602 };
 603
 604 static void hpet_reset(DeviceState *d)
 605 {
 606     HPETState *s = FROM_SYSBUS(HPETState, sysbus_from_qdev(d));
 607     int i;
 608     static int count = 0;
 609
 610     for (i = 0; i < s->num_timers; i++) {
 611         HPETTimer *timer = &s->timer[i];
 612
 613         hpet_del_timer(timer);
 614         timer->cmp = ~0ULL;
 615         timer->config = HPET_TN_PERIODIC_CAP | HPET_TN_SIZE_CAP;
 616         if (s->flags & (1 << HPET_MSI_SUPPORT)) {
 617             timer->config |= HPET_TN_FSB_CAP;
 618         }
 619         /* advertise availability of ioapic inti2 */
 620         timer->config |=  0x00000004ULL << 32;
 621         timer->period = 0ULL;
 622         timer->wrap_flag = 0;
 623     }
 624
 625     s->hpet_counter = 0ULL;
 626     s->hpet_offset = 0ULL;
 627     s->config = 0ULL;
 628     if (count > 0) {
 629         /* we don't enable pit when hpet_reset is first called (by hpet_init)
 630          * because hpet is taking over for pit here. On subsequent invocations,
 631          * hpet_reset is called due to system reset. At this point control must
 632          * be returned to pit until SW reenables hpet.
 633          */
 634         hpet_pit_enable();
 635     }
 636     hpet_cfg.hpet[s->hpet_id].event_timer_block_id = (uint32_t)s->capability;
 637     hpet_cfg.hpet[s->hpet_id].address = sysbus_from_qdev(d)->mmio[0].addr;
 638     count = 1;
 639 }
 640
 641 static void hpet_handle_rtc_irq(void *opaque, int n, int level)
 642 {
 643     HPETState *s = FROM_SYSBUS(HPETState, opaque);
 644
 645     s->rtc_irq_level = level;
 646     if (!hpet_in_legacy_mode(s)) {
 647         qemu_set_irq(s->irqs[RTC_ISA_IRQ], level);
 648     }
 649 }
 650
 651 static int hpet_init(SysBusDevice *dev)
 652 {
 653     HPETState *s = FROM_SYSBUS(HPETState, dev);
 654     int i;
 655     HPETTimer *timer;
 656
 657     if (hpet_cfg.count == UINT8_MAX) {
 658         /* first instance */
 659         hpet_cfg.count = 0;
 660     }
 661
 662     if (hpet_cfg.count == 8) {
 663         fprintf(stderr, "Only 8 instances of HPET is allowed\n");
 664         return -1;
 665     }
 666
 667     s->hpet_id = hpet_cfg.count++;
 668
 669     for (i = 0; i < HPET_NUM_IRQ_ROUTES; i++) {
 670         sysbus_init_irq(dev, &s->irqs[i]);
 671     }
 672
 673     if (s->num_timers < HPET_MIN_TIMERS) {
 674         s->num_timers = HPET_MIN_TIMERS;
 675     } else if (s->num_timers > HPET_MAX_TIMERS) {
 676         s->num_timers = HPET_MAX_TIMERS;
 677     }
 678     for (i = 0; i < HPET_MAX_TIMERS; i++) {
 679         timer = &s->timer[i];
 680         timer->qemu_timer = qemu_new_timer_ns(vm_clock, hpet_timer, timer);
 681         timer->tn = i;
 682         timer->state = s;
 683     }
 684
 685     /* 64-bit main counter; LegacyReplacementRoute. */
 686     s->capability = 0x8086a001ULL;
 687     s->capability |= (s->num_timers - 1) << HPET_ID_NUM_TIM_SHIFT;
 688     s->capability |= ((HPET_CLK_PERIOD) << 32);
 689
 690     qdev_init_gpio_in(&dev->qdev, hpet_handle_rtc_irq, 1);
 691
 692     /* HPET Area */
 693     memory_region_init_io(&s->iomem, &hpet_ram_ops, s, "hpet", 0x400);
 694     sysbus_init_mmio(dev, &s->iomem);
 695     return 0;
 696 }
 697
 698 static SysBusDeviceInfo hpet_device_info = {
 699     .qdev.name    = "hpet",
 700     .qdev.size    = sizeof(HPETState),
 701     .qdev.no_user = 1,
 702     .qdev.vmsd    = &vmstate_hpet,
 703     .qdev.reset   = hpet_reset,
 704     .init         = hpet_init,
 705     .qdev.props = (Property[]) {
 706         DEFINE_PROP_UINT8("timers", HPETState, num_timers, HPET_MIN_TIMERS),
 707         DEFINE_PROP_BIT("msi", HPETState, flags, HPET_MSI_SUPPORT, false),
 708         DEFINE_PROP_END_OF_LIST(),
 709     },
 710 };
 711
 712 static void hpet_register_device(void)
 713 {
 714     sysbus_register_withprop(&hpet_device_info);
 715 }
 716
 717 device_init(hpet_register_device)