hw/timer/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/hw.h"
  28 #include "hw/i386/pc.h"
  29 #include "ui/console.h"
  30 #include "qemu/timer.h"
  31 #include "hw/timer/hpet.h"
  32 #include "hw/sysbus.h"
  33 #include "hw/timer/mc146818rtc.h"
  34 #include "hw/timer/i8254.h"
  35
  36 //#define HPET_DEBUG
  37 #ifdef HPET_DEBUG
  38 #define DPRINTF printf
  39 #else
  40 #define DPRINTF(...)
  41 #endif
  42
  43 #define HPET_MSI_SUPPORT        0
  44
  45 #define TYPE_HPET "hpet"
  46 #define HPET(obj) OBJECT_CHECK(HPETState, (obj), TYPE_HPET)
  47
  48 struct HPETState;
  49 typedef struct HPETTimer {  /* timers */
  50     uint8_t tn;             /*timer number*/
  51     QEMUTimer *qemu_timer;
  52     struct HPETState *state;
  53     /* Memory-mapped, software visible timer registers */
  54     uint64_t config;        /* configuration/cap */
  55     uint64_t cmp;           /* comparator */
  56     uint64_t fsb;           /* FSB route */
  57     /* Hidden register state */
  58     uint64_t period;        /* Last value written to comparator */
  59     uint8_t wrap_flag;      /* timer pop will indicate wrap for one-shot 32-bit
  60                              * mode. Next pop will be actual timer expiration.
  61                              */
  62 } HPETTimer;
  63
  64 typedef struct HPETState {
  65     /*< private >*/
  66     SysBusDevice parent_obj;
  67     /*< public >*/
  68
  69     MemoryRegion iomem;
  70     uint64_t hpet_offset;
  71     qemu_irq irqs[HPET_NUM_IRQ_ROUTES];
  72     uint32_t flags;
  73     uint8_t rtc_irq_level;
  74     qemu_irq pit_enabled;
  75     uint8_t num_timers;
  76     HPETTimer timer[HPET_MAX_TIMERS];
  77
  78     /* Memory-mapped, software visible registers */
  79     uint64_t capability;        /* capabilities */
  80     uint64_t config;            /* configuration */
  81     uint64_t isr;               /* interrupt status reg */
  82     uint64_t hpet_counter;      /* main counter */
  83     uint8_t  hpet_id;           /* instance id */
  84 } HPETState;
  85
  86 static uint32_t hpet_in_legacy_mode(HPETState *s)
  87 {
  88     return s->config & HPET_CFG_LEGACY;
  89 }
  90
  91 static uint32_t timer_int_route(struct HPETTimer *timer)
  92 {
  93     return (timer->config & HPET_TN_INT_ROUTE_MASK) >> HPET_TN_INT_ROUTE_SHIFT;
  94 }
  95
  96 static uint32_t timer_fsb_route(HPETTimer *t)
  97 {
  98     return t->config & HPET_TN_FSB_ENABLE;
  99 }
 100
 101 static uint32_t hpet_enabled(HPETState *s)
 102 {
 103     return s->config & HPET_CFG_ENABLE;
 104 }
 105
 106 static uint32_t timer_is_periodic(HPETTimer *t)
 107 {
 108     return t->config & HPET_TN_PERIODIC;
 109 }
 110
 111 static uint32_t timer_enabled(HPETTimer *t)
 112 {
 113     return t->config & HPET_TN_ENABLE;
 114 }
 115
 116 static uint32_t hpet_time_after(uint64_t a, uint64_t b)
 117 {
 118     return ((int32_t)(b) - (int32_t)(a) < 0);
 119 }
 120
 121 static uint32_t hpet_time_after64(uint64_t a, uint64_t b)
 122 {
 123     return ((int64_t)(b) - (int64_t)(a) < 0);
 124 }
 125
 126 static uint64_t ticks_to_ns(uint64_t value)
 127 {
 128     return (muldiv64(value, HPET_CLK_PERIOD, FS_PER_NS));
 129 }
 130
 131 static uint64_t ns_to_ticks(uint64_t value)
 132 {
 133     return (muldiv64(value, FS_PER_NS, HPET_CLK_PERIOD));
 134 }
 135
 136 static uint64_t hpet_fixup_reg(uint64_t new, uint64_t old, uint64_t mask)
 137 {
 138     new &= mask;
 139     new |= old & ~mask;
 140     return new;
 141 }
 142
 143 static int activating_bit(uint64_t old, uint64_t new, uint64_t mask)
 144 {
 145     return (!(old & mask) && (new & mask));
 146 }
 147
 148 static int deactivating_bit(uint64_t old, uint64_t new, uint64_t mask)
 149 {
 150     return ((old & mask) && !(new & mask));
 151 }
 152
 153 static uint64_t hpet_get_ticks(HPETState *s)
 154 {
 155     return ns_to_ticks(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + s->hpet_offset);
 156 }
 157
 158 /*
 159  * calculate diff between comparator value and current ticks
 160  */
 161 static inline uint64_t hpet_calculate_diff(HPETTimer *t, uint64_t current)
 162 {
 163
 164     if (t->config & HPET_TN_32BIT) {
 165         uint32_t diff, cmp;
 166
 167         cmp = (uint32_t)t->cmp;
 168         diff = cmp - (uint32_t)current;
 169         diff = (int32_t)diff > 0 ? diff : (uint32_t)1;
 170         return (uint64_t)diff;
 171     } else {
 172         uint64_t diff, cmp;
 173
 174         cmp = t->cmp;
 175         diff = cmp - current;
 176         diff = (int64_t)diff > 0 ? diff : (uint64_t)1;
 177         return diff;
 178     }
 179 }
 180
 181 static void update_irq(struct HPETTimer *timer, int set)
 182 {
 183     uint64_t mask;
 184     HPETState *s;
 185     int route;
 186
 187     if (timer->tn <= 1 && hpet_in_legacy_mode(timer->state)) {
 188         /* if LegacyReplacementRoute bit is set, HPET specification requires
 189          * timer0 be routed to IRQ0 in NON-APIC or IRQ2 in the I/O APIC,
 190          * timer1 be routed to IRQ8 in NON-APIC or IRQ8 in the I/O APIC.
 191          */
 192         route = (timer->tn == 0) ? 0 : RTC_ISA_IRQ;
 193     } else {
 194         route = timer_int_route(timer);
 195     }
 196     s = timer->state;
 197     mask = 1 << timer->tn;
 198     if (!set || !timer_enabled(timer) || !hpet_enabled(timer->state)) {
 199         s->isr &= ~mask;
 200         if (!timer_fsb_route(timer)) {
 201             qemu_irq_lower(s->irqs[route]);
 202         }
 203     } else if (timer_fsb_route(timer)) {
 204         stl_le_phys(timer->fsb >> 32, timer->fsb & 0xffffffff);
 205     } else if (timer->config & HPET_TN_TYPE_LEVEL) {
 206         s->isr |= mask;
 207         qemu_irq_raise(s->irqs[route]);
 208     } else {
 209         s->isr &= ~mask;
 210         qemu_irq_pulse(s->irqs[route]);
 211     }
 212 }
 213
 214 static void hpet_pre_save(void *opaque)
 215 {
 216     HPETState *s = opaque;
 217
 218     /* save current counter value */
 219     s->hpet_counter = hpet_get_ticks(s);
 220 }
 221
 222 static int hpet_pre_load(void *opaque)
 223 {
 224     HPETState *s = opaque;
 225
 226     /* version 1 only supports 3, later versions will load the actual value */
 227     s->num_timers = HPET_MIN_TIMERS;
 228     return 0;
 229 }
 230
 231 static int hpet_post_load(void *opaque, int version_id)
 232 {
 233     HPETState *s = opaque;
 234
 235     /* Recalculate the offset between the main counter and guest time */
 236     s->hpet_offset = ticks_to_ns(s->hpet_counter) - qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
 237
 238     /* Push number of timers into capability returned via HPET_ID */
 239     s->capability &= ~HPET_ID_NUM_TIM_MASK;
 240     s->capability |= (s->num_timers - 1) << HPET_ID_NUM_TIM_SHIFT;
 241     hpet_cfg.hpet[s->hpet_id].event_timer_block_id = (uint32_t)s->capability;
 242
 243     /* Derive HPET_MSI_SUPPORT from the capability of the first timer. */
 244     s->flags &= ~(1 << HPET_MSI_SUPPORT);
 245     if (s->timer[0].config & HPET_TN_FSB_CAP) {
 246         s->flags |= 1 << HPET_MSI_SUPPORT;
 247     }
 248     return 0;
 249 }
 250
 251 static bool hpet_rtc_irq_level_needed(void *opaque)
 252 {
 253     HPETState *s = opaque;
 254
 255     return s->rtc_irq_level != 0;
 256 }
 257
 258 static const VMStateDescription vmstate_hpet_rtc_irq_level = {
 259     .name = "hpet/rtc_irq_level",
 260     .version_id = 1,
 261     .minimum_version_id = 1,
 262     .minimum_version_id_old = 1,
 263     .fields      = (VMStateField[]) {
 264         VMSTATE_UINT8(rtc_irq_level, HPETState),
 265         VMSTATE_END_OF_LIST()
 266     }
 267 };
 268
 269 static const VMStateDescription vmstate_hpet_timer = {
 270     .name = "hpet_timer",
 271     .version_id = 1,
 272     .minimum_version_id = 1,
 273     .minimum_version_id_old = 1,
 274     .fields      = (VMStateField []) {
 275         VMSTATE_UINT8(tn, HPETTimer),
 276         VMSTATE_UINT64(config, HPETTimer),
 277         VMSTATE_UINT64(cmp, HPETTimer),
 278         VMSTATE_UINT64(fsb, HPETTimer),
 279         VMSTATE_UINT64(period, HPETTimer),
 280         VMSTATE_UINT8(wrap_flag, HPETTimer),
 281         VMSTATE_TIMER(qemu_timer, HPETTimer),
 282         VMSTATE_END_OF_LIST()
 283     }
 284 };
 285
 286 static const VMStateDescription vmstate_hpet = {
 287     .name = "hpet",
 288     .version_id = 2,
 289     .minimum_version_id = 1,
 290     .minimum_version_id_old = 1,
 291     .pre_save = hpet_pre_save,
 292     .pre_load = hpet_pre_load,
 293     .post_load = hpet_post_load,
 294     .fields      = (VMStateField []) {
 295         VMSTATE_UINT64(config, HPETState),
 296         VMSTATE_UINT64(isr, HPETState),
 297         VMSTATE_UINT64(hpet_counter, HPETState),
 298         VMSTATE_UINT8_V(num_timers, HPETState, 2),
 299         VMSTATE_STRUCT_VARRAY_UINT8(timer, HPETState, num_timers, 0,
 300                                     vmstate_hpet_timer, HPETTimer),
 301         VMSTATE_END_OF_LIST()
 302     },
 303     .subsections = (VMStateSubsection[]) {
 304         {
 305             .vmsd = &vmstate_hpet_rtc_irq_level,
 306             .needed = hpet_rtc_irq_level_needed,
 307         }, {
 308             /* empty */
 309         }
 310     }
 311 };
 312
 313 /*
 314  * timer expiration callback
 315  */
 316 static void hpet_timer(void *opaque)
 317 {
 318     HPETTimer *t = opaque;
 319     uint64_t diff;
 320
 321     uint64_t period = t->period;
 322     uint64_t cur_tick = hpet_get_ticks(t->state);
 323
 324     if (timer_is_periodic(t) && period != 0) {
 325         if (t->config & HPET_TN_32BIT) {
 326             while (hpet_time_after(cur_tick, t->cmp)) {
 327                 t->cmp = (uint32_t)(t->cmp + t->period);
 328             }
 329         } else {
 330             while (hpet_time_after64(cur_tick, t->cmp)) {
 331                 t->cmp += period;
 332             }
 333         }
 334         diff = hpet_calculate_diff(t, cur_tick);
 335         timer_mod(t->qemu_timer,
 336                        qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + (int64_t)ticks_to_ns(diff));
 337     } else if (t->config & HPET_TN_32BIT && !timer_is_periodic(t)) {
 338         if (t->wrap_flag) {
 339             diff = hpet_calculate_diff(t, cur_tick);
 340             timer_mod(t->qemu_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
 341                            (int64_t)ticks_to_ns(diff));
 342             t->wrap_flag = 0;
 343         }
 344     }
 345     update_irq(t, 1);
 346 }
 347
 348 static void hpet_set_timer(HPETTimer *t)
 349 {
 350     uint64_t diff;
 351     uint32_t wrap_diff;  /* how many ticks until we wrap? */
 352     uint64_t cur_tick = hpet_get_ticks(t->state);
 353
 354     /* whenever new timer is being set up, make sure wrap_flag is 0 */
 355     t->wrap_flag = 0;
 356     diff = hpet_calculate_diff(t, cur_tick);
 357
 358     /* hpet spec says in one-shot 32-bit mode, generate an interrupt when
 359      * counter wraps in addition to an interrupt with comparator match.
 360      */
 361     if (t->config & HPET_TN_32BIT && !timer_is_periodic(t)) {
 362         wrap_diff = 0xffffffff - (uint32_t)cur_tick;
 363         if (wrap_diff < (uint32_t)diff) {
 364             diff = wrap_diff;
 365             t->wrap_flag = 1;
 366         }
 367     }
 368     timer_mod(t->qemu_timer,
 369                    qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + (int64_t)ticks_to_ns(diff));
 370 }
 371
 372 static void hpet_del_timer(HPETTimer *t)
 373 {
 374     timer_del(t->qemu_timer);
 375     update_irq(t, 0);
 376 }
 377
 378 #ifdef HPET_DEBUG
 379 static uint32_t hpet_ram_readb(void *opaque, hwaddr addr)
 380 {
 381     printf("qemu: hpet_read b at %" PRIx64 "\n", addr);
 382     return 0;
 383 }
 384
 385 static uint32_t hpet_ram_readw(void *opaque, hwaddr addr)
 386 {
 387     printf("qemu: hpet_read w at %" PRIx64 "\n", addr);
 388     return 0;
 389 }
 390 #endif
 391
 392 static uint64_t hpet_ram_read(void *opaque, hwaddr addr,
 393                               unsigned size)
 394 {
 395     HPETState *s = opaque;
 396     uint64_t cur_tick, index;
 397
 398     DPRINTF("qemu: Enter hpet_ram_readl at %" PRIx64 "\n", addr);
 399     index = addr;
 400     /*address range of all TN regs*/
 401     if (index >= 0x100 && index <= 0x3ff) {
 402         uint8_t timer_id = (addr - 0x100) / 0x20;
 403         HPETTimer *timer = &s->timer[timer_id];
 404
 405         if (timer_id > s->num_timers) {
 406             DPRINTF("qemu: timer id out of range\n");
 407             return 0;
 408         }
 409
 410         switch ((addr - 0x100) % 0x20) {
 411         case HPET_TN_CFG:
 412             return timer->config;
 413         case HPET_TN_CFG + 4: // Interrupt capabilities
 414             return timer->config >> 32;
 415         case HPET_TN_CMP: // comparator register
 416             return timer->cmp;
 417         case HPET_TN_CMP + 4:
 418             return timer->cmp >> 32;
 419         case HPET_TN_ROUTE:
 420             return timer->fsb;
 421         case HPET_TN_ROUTE + 4:
 422             return timer->fsb >> 32;
 423         default:
 424             DPRINTF("qemu: invalid hpet_ram_readl\n");
 425             break;
 426         }
 427     } else {
 428         switch (index) {
 429         case HPET_ID:
 430             return s->capability;
 431         case HPET_PERIOD:
 432             return s->capability >> 32;
 433         case HPET_CFG:
 434             return s->config;
 435         case HPET_CFG + 4:
 436             DPRINTF("qemu: invalid HPET_CFG + 4 hpet_ram_readl\n");
 437             return 0;
 438         case HPET_COUNTER:
 439             if (hpet_enabled(s)) {
 440                 cur_tick = hpet_get_ticks(s);
 441             } else {
 442                 cur_tick = s->hpet_counter;
 443             }
 444             DPRINTF("qemu: reading counter  = %" PRIx64 "\n", cur_tick);
 445             return cur_tick;
 446         case HPET_COUNTER + 4:
 447             if (hpet_enabled(s)) {
 448                 cur_tick = hpet_get_ticks(s);
 449             } else {
 450                 cur_tick = s->hpet_counter;
 451             }
 452             DPRINTF("qemu: reading counter + 4  = %" PRIx64 "\n", cur_tick);
 453             return cur_tick >> 32;
 454         case HPET_STATUS:
 455             return s->isr;
 456         default:
 457             DPRINTF("qemu: invalid hpet_ram_readl\n");
 458             break;
 459         }
 460     }
 461     return 0;
 462 }
 463
 464 static void hpet_ram_write(void *opaque, hwaddr addr,
 465                            uint64_t value, unsigned size)
 466 {
 467     int i;
 468     HPETState *s = opaque;
 469     uint64_t old_val, new_val, val, index;
 470
 471     DPRINTF("qemu: Enter hpet_ram_writel at %" PRIx64 " = %#x\n", addr, value);
 472     index = addr;
 473     old_val = hpet_ram_read(opaque, addr, 4);
 474     new_val = value;
 475
 476     /*address range of all TN regs*/
 477     if (index >= 0x100 && index <= 0x3ff) {
 478         uint8_t timer_id = (addr - 0x100) / 0x20;
 479         HPETTimer *timer = &s->timer[timer_id];
 480
 481         DPRINTF("qemu: hpet_ram_writel timer_id = %#x\n", timer_id);
 482         if (timer_id > s->num_timers) {
 483             DPRINTF("qemu: timer id out of range\n");
 484             return;
 485         }
 486         switch ((addr - 0x100) % 0x20) {
 487         case HPET_TN_CFG:
 488             DPRINTF("qemu: hpet_ram_writel HPET_TN_CFG\n");
 489             if (activating_bit(old_val, new_val, HPET_TN_FSB_ENABLE)) {
 490                 update_irq(timer, 0);
 491             }
 492             val = hpet_fixup_reg(new_val, old_val, HPET_TN_CFG_WRITE_MASK);
 493             timer->config = (timer->config & 0xffffffff00000000ULL) | val;
 494             if (new_val & HPET_TN_32BIT) {
 495                 timer->cmp = (uint32_t)timer->cmp;
 496                 timer->period = (uint32_t)timer->period;
 497             }
 498             if (activating_bit(old_val, new_val, HPET_TN_ENABLE)) {
 499                 hpet_set_timer(timer);
 500             } else if (deactivating_bit(old_val, new_val, HPET_TN_ENABLE)) {
 501                 hpet_del_timer(timer);
 502             }
 503             break;
 504         case HPET_TN_CFG + 4: // Interrupt capabilities
 505             DPRINTF("qemu: invalid HPET_TN_CFG+4 write\n");
 506             break;
 507         case HPET_TN_CMP: // comparator register
 508             DPRINTF("qemu: hpet_ram_writel HPET_TN_CMP\n");
 509             if (timer->config & HPET_TN_32BIT) {
 510                 new_val = (uint32_t)new_val;
 511             }
 512             if (!timer_is_periodic(timer)
 513                 || (timer->config & HPET_TN_SETVAL)) {
 514                 timer->cmp = (timer->cmp & 0xffffffff00000000ULL) | new_val;
 515             }
 516             if (timer_is_periodic(timer)) {
 517                 /*
 518                  * FIXME: Clamp period to reasonable min value?
 519                  * Clamp period to reasonable max value
 520                  */
 521                 new_val &= (timer->config & HPET_TN_32BIT ? ~0u : ~0ull) >> 1;
 522                 timer->period =
 523                     (timer->period & 0xffffffff00000000ULL) | new_val;
 524             }
 525             timer->config &= ~HPET_TN_SETVAL;
 526             if (hpet_enabled(s)) {
 527                 hpet_set_timer(timer);
 528             }
 529             break;
 530         case HPET_TN_CMP + 4: // comparator register high order
 531             DPRINTF("qemu: hpet_ram_writel HPET_TN_CMP + 4\n");
 532             if (!timer_is_periodic(timer)
 533                 || (timer->config & HPET_TN_SETVAL)) {
 534                 timer->cmp = (timer->cmp & 0xffffffffULL) | new_val << 32;
 535             } else {
 536                 /*
 537                  * FIXME: Clamp period to reasonable min value?
 538                  * Clamp period to reasonable max value
 539                  */
 540                 new_val &= (timer->config & HPET_TN_32BIT ? ~0u : ~0ull) >> 1;
 541                 timer->period =
 542                     (timer->period & 0xffffffffULL) | new_val << 32;
 543                 }
 544                 timer->config &= ~HPET_TN_SETVAL;
 545                 if (hpet_enabled(s)) {
 546                     hpet_set_timer(timer);
 547                 }
 548                 break;
 549         case HPET_TN_ROUTE:
 550             timer->fsb = (timer->fsb & 0xffffffff00000000ULL) | new_val;
 551             break;
 552         case HPET_TN_ROUTE + 4:
 553             timer->fsb = (new_val << 32) | (timer->fsb & 0xffffffff);
 554             break;
 555         default:
 556             DPRINTF("qemu: invalid hpet_ram_writel\n");
 557             break;
 558         }
 559         return;
 560     } else {
 561         switch (index) {
 562         case HPET_ID:
 563             return;
 564         case HPET_CFG:
 565             val = hpet_fixup_reg(new_val, old_val, HPET_CFG_WRITE_MASK);
 566             s->config = (s->config & 0xffffffff00000000ULL) | val;
 567             if (activating_bit(old_val, new_val, HPET_CFG_ENABLE)) {
 568                 /* Enable main counter and interrupt generation. */
 569                 s->hpet_offset =
 570                     ticks_to_ns(s->hpet_counter) - qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
 571                 for (i = 0; i < s->num_timers; i++) {
 572                     if ((&s->timer[i])->cmp != ~0ULL) {
 573                         hpet_set_timer(&s->timer[i]);
 574                     }
 575                 }
 576             } else if (deactivating_bit(old_val, new_val, HPET_CFG_ENABLE)) {
 577                 /* Halt main counter and disable interrupt generation. */
 578                 s->hpet_counter = hpet_get_ticks(s);
 579                 for (i = 0; i < s->num_timers; i++) {
 580                     hpet_del_timer(&s->timer[i]);
 581                 }
 582             }
 583             /* i8254 and RTC output pins are disabled
 584              * when HPET is in legacy mode */
 585             if (activating_bit(old_val, new_val, HPET_CFG_LEGACY)) {
 586                 qemu_set_irq(s->pit_enabled, 0);
 587                 qemu_irq_lower(s->irqs[0]);
 588                 qemu_irq_lower(s->irqs[RTC_ISA_IRQ]);
 589             } else if (deactivating_bit(old_val, new_val, HPET_CFG_LEGACY)) {
 590                 qemu_irq_lower(s->irqs[0]);
 591                 qemu_set_irq(s->pit_enabled, 1);
 592                 qemu_set_irq(s->irqs[RTC_ISA_IRQ], s->rtc_irq_level);
 593             }
 594             break;
 595         case HPET_CFG + 4:
 596             DPRINTF("qemu: invalid HPET_CFG+4 write\n");
 597             break;
 598         case HPET_STATUS:
 599             val = new_val & s->isr;
 600             for (i = 0; i < s->num_timers; i++) {
 601                 if (val & (1 << i)) {
 602                     update_irq(&s->timer[i], 0);
 603                 }
 604             }
 605             break;
 606         case HPET_COUNTER:
 607             if (hpet_enabled(s)) {
 608                 DPRINTF("qemu: Writing counter while HPET enabled!\n");
 609             }
 610             s->hpet_counter =
 611                 (s->hpet_counter & 0xffffffff00000000ULL) | value;
 612             DPRINTF("qemu: HPET counter written. ctr = %#x -> %" PRIx64 "\n",
 613                     value, s->hpet_counter);
 614             break;
 615         case HPET_COUNTER + 4:
 616             if (hpet_enabled(s)) {
 617                 DPRINTF("qemu: Writing counter while HPET enabled!\n");
 618             }
 619             s->hpet_counter =
 620                 (s->hpet_counter & 0xffffffffULL) | (((uint64_t)value) << 32);
 621             DPRINTF("qemu: HPET counter + 4 written. ctr = %#x -> %" PRIx64 "\n",
 622                     value, s->hpet_counter);
 623             break;
 624         default:
 625             DPRINTF("qemu: invalid hpet_ram_writel\n");
 626             break;
 627         }
 628     }
 629 }
 630
 631 static const MemoryRegionOps hpet_ram_ops = {
 632     .read = hpet_ram_read,
 633     .write = hpet_ram_write,
 634     .valid = {
 635         .min_access_size = 4,
 636         .max_access_size = 4,
 637     },
 638     .endianness = DEVICE_NATIVE_ENDIAN,
 639 };
 640
 641 static void hpet_reset(DeviceState *d)
 642 {
 643     HPETState *s = HPET(d);
 644     SysBusDevice *sbd = SYS_BUS_DEVICE(d);
 645     int i;
 646
 647     for (i = 0; i < s->num_timers; i++) {
 648         HPETTimer *timer = &s->timer[i];
 649
 650         hpet_del_timer(timer);
 651         timer->cmp = ~0ULL;
 652         timer->config = HPET_TN_PERIODIC_CAP | HPET_TN_SIZE_CAP;
 653         if (s->flags & (1 << HPET_MSI_SUPPORT)) {
 654             timer->config |= HPET_TN_FSB_CAP;
 655         }
 656         /* advertise availability of ioapic inti2 */
 657         timer->config |=  0x00000004ULL << 32;
 658         timer->period = 0ULL;
 659         timer->wrap_flag = 0;
 660     }
 661
 662     qemu_set_irq(s->pit_enabled, 1);
 663     s->hpet_counter = 0ULL;
 664     s->hpet_offset = 0ULL;
 665     s->config = 0ULL;
 666     hpet_cfg.hpet[s->hpet_id].event_timer_block_id = (uint32_t)s->capability;
 667     hpet_cfg.hpet[s->hpet_id].address = sbd->mmio[0].addr;
 668
 669     /* to document that the RTC lowers its output on reset as well */
 670     s->rtc_irq_level = 0;
 671 }
 672
 673 static void hpet_handle_legacy_irq(void *opaque, int n, int level)
 674 {
 675     HPETState *s = HPET(opaque);
 676
 677     if (n == HPET_LEGACY_PIT_INT) {
 678         if (!hpet_in_legacy_mode(s)) {
 679             qemu_set_irq(s->irqs[0], level);
 680         }
 681     } else {
 682         s->rtc_irq_level = level;
 683         if (!hpet_in_legacy_mode(s)) {
 684             qemu_set_irq(s->irqs[RTC_ISA_IRQ], level);
 685         }
 686     }
 687 }
 688
 689 static void hpet_init(Object *obj)
 690 {
 691     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
 692     HPETState *s = HPET(obj);
 693
 694     /* HPET Area */
 695     memory_region_init_io(&s->iomem, obj, &hpet_ram_ops, s, "hpet", 0x400);
 696     sysbus_init_mmio(sbd, &s->iomem);
 697 }
 698
 699 static void hpet_realize(DeviceState *dev, Error **errp)
 700 {
 701     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
 702     HPETState *s = HPET(dev);
 703     int i;
 704     HPETTimer *timer;
 705
 706     if (hpet_cfg.count == UINT8_MAX) {
 707         /* first instance */
 708         hpet_cfg.count = 0;
 709     }
 710
 711     if (hpet_cfg.count == 8) {
 712         error_setg(errp, "Only 8 instances of HPET is allowed");
 713         return;
 714     }
 715
 716     s->hpet_id = hpet_cfg.count++;
 717
 718     for (i = 0; i < HPET_NUM_IRQ_ROUTES; i++) {
 719         sysbus_init_irq(sbd, &s->irqs[i]);
 720     }
 721
 722     if (s->num_timers < HPET_MIN_TIMERS) {
 723         s->num_timers = HPET_MIN_TIMERS;
 724     } else if (s->num_timers > HPET_MAX_TIMERS) {
 725         s->num_timers = HPET_MAX_TIMERS;
 726     }
 727     for (i = 0; i < HPET_MAX_TIMERS; i++) {
 728         timer = &s->timer[i];
 729         timer->qemu_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, hpet_timer, timer);
 730         timer->tn = i;
 731         timer->state = s;
 732     }
 733
 734     /* 64-bit main counter; LegacyReplacementRoute. */
 735     s->capability = 0x8086a001ULL;
 736     s->capability |= (s->num_timers - 1) << HPET_ID_NUM_TIM_SHIFT;
 737     s->capability |= ((HPET_CLK_PERIOD) << 32);
 738
 739     qdev_init_gpio_in(dev, hpet_handle_legacy_irq, 2);
 740     qdev_init_gpio_out(dev, &s->pit_enabled, 1);
 741 }
 742
 743 static Property hpet_device_properties[] = {
 744     DEFINE_PROP_UINT8("timers", HPETState, num_timers, HPET_MIN_TIMERS),
 745     DEFINE_PROP_BIT("msi", HPETState, flags, HPET_MSI_SUPPORT, false),
 746     DEFINE_PROP_END_OF_LIST(),
 747 };
 748
 749 static void hpet_device_class_init(ObjectClass *klass, void *data)
 750 {
 751     DeviceClass *dc = DEVICE_CLASS(klass);
 752
 753     dc->realize = hpet_realize;
 754     dc->no_user = 1;
 755     dc->reset = hpet_reset;
 756     dc->vmsd = &vmstate_hpet;
 757     dc->props = hpet_device_properties;
 758 }
 759
 760 bool hpet_find(void)
 761 {
 762     return object_resolve_path_type("", TYPE_HPET, NULL);
 763 }
 764
 765 static const TypeInfo hpet_device_info = {
 766     .name          = TYPE_HPET,
 767     .parent        = TYPE_SYS_BUS_DEVICE,
 768     .instance_size = sizeof(HPETState),
 769     .instance_init = hpet_init,
 770     .class_init    = hpet_device_class_init,
 771 };
 772
 773 static void hpet_register_types(void)
 774 {
 775     type_register_static(&hpet_device_info);
 776 }
 777
 778 type_init(hpet_register_types)