hw/exynos4210_rtc.c

   1 /*
   2  * Samsung exynos4210 Real Time Clock
   3  *
   4  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
   5  *  Ogurtsov Oleg <o.ogurtsov@samsung.com>
   6  *
   7  *  This program is free software; you can redistribute it and/or modify it
   8  *  under the terms of the GNU General Public License as published by the
   9  *  Free Software Foundation; either version 2 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  This program is distributed in the hope that it will be useful, but WITHOUT
  13  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  *  FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  15  *  for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License along
  18  *  with this program; if not, see <http://www.gnu.org/licenses/>.
  19  *
  20  */
  21
  22 /* Description:
  23  * Register RTCCON:
  24  *  CLKSEL Bit[1] not used
  25  *  CLKOUTEN Bit[9] not used
  26  */
  27
  28 #include "hw/sysbus.h"
  29 #include "qemu/timer.h"
  30 #include "qemu-common.h"
  31 #include "hw/ptimer.h"
  32
  33 #include "hw/hw.h"
  34 #include "qemu/timer.h"
  35 #include "sysemu/sysemu.h"
  36
  37 #include "hw/exynos4210.h"
  38
  39 #define DEBUG_RTC 0
  40
  41 #if DEBUG_RTC
  42 #define DPRINTF(fmt, ...) \
  43         do { fprintf(stdout, "RTC: [%24s:%5d] " fmt, __func__, __LINE__, \
  44                 ## __VA_ARGS__); } while (0)
  45 #else
  46 #define DPRINTF(fmt, ...) do {} while (0)
  47 #endif
  48
  49 #define     EXYNOS4210_RTC_REG_MEM_SIZE     0x0100
  50
  51 #define     INTP            0x0030
  52 #define     RTCCON          0x0040
  53 #define     TICCNT          0x0044
  54 #define     RTCALM          0x0050
  55 #define     ALMSEC          0x0054
  56 #define     ALMMIN          0x0058
  57 #define     ALMHOUR         0x005C
  58 #define     ALMDAY          0x0060
  59 #define     ALMMON          0x0064
  60 #define     ALMYEAR         0x0068
  61 #define     BCDSEC          0x0070
  62 #define     BCDMIN          0x0074
  63 #define     BCDHOUR         0x0078
  64 #define     BCDDAY          0x007C
  65 #define     BCDDAYWEEK      0x0080
  66 #define     BCDMON          0x0084
  67 #define     BCDYEAR         0x0088
  68 #define     CURTICNT        0x0090
  69
  70 #define     TICK_TIMER_ENABLE   0x0100
  71 #define     TICNT_THRESHHOLD    2
  72
  73
  74 #define     RTC_ENABLE          0x0001
  75
  76 #define     INTP_TICK_ENABLE    0x0001
  77 #define     INTP_ALM_ENABLE     0x0002
  78
  79 #define     ALARM_INT_ENABLE    0x0040
  80
  81 #define     RTC_BASE_FREQ       32768
  82
  83 typedef struct Exynos4210RTCState {
  84     SysBusDevice busdev;
  85     MemoryRegion iomem;
  86
  87     /* registers */
  88     uint32_t    reg_intp;
  89     uint32_t    reg_rtccon;
  90     uint32_t    reg_ticcnt;
  91     uint32_t    reg_rtcalm;
  92     uint32_t    reg_almsec;
  93     uint32_t    reg_almmin;
  94     uint32_t    reg_almhour;
  95     uint32_t    reg_almday;
  96     uint32_t    reg_almmon;
  97     uint32_t    reg_almyear;
  98     uint32_t    reg_curticcnt;
  99
 100     ptimer_state    *ptimer;        /* tick timer */
 101     ptimer_state    *ptimer_1Hz;    /* clock timer */
 102     uint32_t        freq;
 103
 104     qemu_irq        tick_irq;   /* Time Tick Generator irq */
 105     qemu_irq        alm_irq;    /* alarm irq */
 106
 107     struct tm   current_tm;     /* current time */
 108 } Exynos4210RTCState;
 109
 110 #define TICCKSEL(value) ((value & (0x0F << 4)) >> 4)
 111
 112 /*** VMState ***/
 113 static const VMStateDescription vmstate_exynos4210_rtc_state = {
 114     .name = "exynos4210.rtc",
 115     .version_id = 1,
 116     .minimum_version_id = 1,
 117     .minimum_version_id_old = 1,
 118     .fields = (VMStateField[]) {
 119         VMSTATE_UINT32(reg_intp, Exynos4210RTCState),
 120         VMSTATE_UINT32(reg_rtccon, Exynos4210RTCState),
 121         VMSTATE_UINT32(reg_ticcnt, Exynos4210RTCState),
 122         VMSTATE_UINT32(reg_rtcalm, Exynos4210RTCState),
 123         VMSTATE_UINT32(reg_almsec, Exynos4210RTCState),
 124         VMSTATE_UINT32(reg_almmin, Exynos4210RTCState),
 125         VMSTATE_UINT32(reg_almhour, Exynos4210RTCState),
 126         VMSTATE_UINT32(reg_almday, Exynos4210RTCState),
 127         VMSTATE_UINT32(reg_almmon, Exynos4210RTCState),
 128         VMSTATE_UINT32(reg_almyear, Exynos4210RTCState),
 129         VMSTATE_UINT32(reg_curticcnt, Exynos4210RTCState),
 130         VMSTATE_PTIMER(ptimer, Exynos4210RTCState),
 131         VMSTATE_PTIMER(ptimer_1Hz, Exynos4210RTCState),
 132         VMSTATE_UINT32(freq, Exynos4210RTCState),
 133         VMSTATE_INT32(current_tm.tm_sec, Exynos4210RTCState),
 134         VMSTATE_INT32(current_tm.tm_min, Exynos4210RTCState),
 135         VMSTATE_INT32(current_tm.tm_hour, Exynos4210RTCState),
 136         VMSTATE_INT32(current_tm.tm_wday, Exynos4210RTCState),
 137         VMSTATE_INT32(current_tm.tm_mday, Exynos4210RTCState),
 138         VMSTATE_INT32(current_tm.tm_mon, Exynos4210RTCState),
 139         VMSTATE_INT32(current_tm.tm_year, Exynos4210RTCState),
 140         VMSTATE_END_OF_LIST()
 141     }
 142 };
 143
 144 #define BCD3DIGITS(x) \
 145     ((uint32_t)to_bcd((uint8_t)(x % 100)) + \
 146     ((uint32_t)to_bcd((uint8_t)((x % 1000) / 100)) << 8))
 147
 148 static void check_alarm_raise(Exynos4210RTCState *s)
 149 {
 150     unsigned int alarm_raise = 0;
 151     struct tm stm = s->current_tm;
 152
 153     if ((s->reg_rtcalm & 0x01) &&
 154         (to_bcd((uint8_t)stm.tm_sec) == (uint8_t)s->reg_almsec)) {
 155         alarm_raise = 1;
 156     }
 157     if ((s->reg_rtcalm & 0x02) &&
 158         (to_bcd((uint8_t)stm.tm_min) == (uint8_t)s->reg_almmin)) {
 159         alarm_raise = 1;
 160     }
 161     if ((s->reg_rtcalm & 0x04) &&
 162         (to_bcd((uint8_t)stm.tm_hour) == (uint8_t)s->reg_almhour)) {
 163         alarm_raise = 1;
 164     }
 165     if ((s->reg_rtcalm & 0x08) &&
 166         (to_bcd((uint8_t)stm.tm_mday) == (uint8_t)s->reg_almday)) {
 167         alarm_raise = 1;
 168     }
 169     if ((s->reg_rtcalm & 0x10) &&
 170          (to_bcd((uint8_t)stm.tm_mon) == (uint8_t)s->reg_almmon)) {
 171         alarm_raise = 1;
 172     }
 173     if ((s->reg_rtcalm & 0x20) &&
 174         (BCD3DIGITS(stm.tm_year) == s->reg_almyear)) {
 175         alarm_raise = 1;
 176     }
 177
 178     if (alarm_raise) {
 179         DPRINTF("ALARM IRQ\n");
 180         /* set irq status */
 181         s->reg_intp |= INTP_ALM_ENABLE;
 182         qemu_irq_raise(s->alm_irq);
 183     }
 184 }
 185
 186 /*
 187  * RTC update frequency
 188  * Parameters:
 189  *     reg_value - current RTCCON register or his new value
 190  */
 191 static void exynos4210_rtc_update_freq(Exynos4210RTCState *s,
 192                                        uint32_t reg_value)
 193 {
 194     uint32_t freq;
 195
 196     freq = s->freq;
 197     /* set frequncy for time generator */
 198     s->freq = RTC_BASE_FREQ / (1 << TICCKSEL(reg_value));
 199
 200     if (freq != s->freq) {
 201         ptimer_set_freq(s->ptimer, s->freq);
 202         DPRINTF("freq=%dHz\n", s->freq);
 203     }
 204 }
 205
 206 /* month is between 0 and 11. */
 207 static int get_days_in_month(int month, int year)
 208 {
 209     static const int days_tab[12] = {
 210         31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
 211     };
 212     int d;
 213     if ((unsigned)month >= 12) {
 214         return 31;
 215     }
 216     d = days_tab[month];
 217     if (month == 1) {
 218         if ((year % 4) == 0 && ((year % 100) != 0 || (year % 400) == 0)) {
 219             d++;
 220         }
 221     }
 222     return d;
 223 }
 224
 225 /* update 'tm' to the next second */
 226 static void rtc_next_second(struct tm *tm)
 227 {
 228     int days_in_month;
 229
 230     tm->tm_sec++;
 231     if ((unsigned)tm->tm_sec >= 60) {
 232         tm->tm_sec = 0;
 233         tm->tm_min++;
 234         if ((unsigned)tm->tm_min >= 60) {
 235             tm->tm_min = 0;
 236             tm->tm_hour++;
 237             if ((unsigned)tm->tm_hour >= 24) {
 238                 tm->tm_hour = 0;
 239                 /* next day */
 240                 tm->tm_wday++;
 241                 if ((unsigned)tm->tm_wday >= 7) {
 242                     tm->tm_wday = 0;
 243                 }
 244                 days_in_month = get_days_in_month(tm->tm_mon,
 245                                                   tm->tm_year + 1900);
 246                 tm->tm_mday++;
 247                 if (tm->tm_mday < 1) {
 248                     tm->tm_mday = 1;
 249                 } else if (tm->tm_mday > days_in_month) {
 250                     tm->tm_mday = 1;
 251                     tm->tm_mon++;
 252                     if (tm->tm_mon >= 12) {
 253                         tm->tm_mon = 0;
 254                         tm->tm_year++;
 255                     }
 256                 }
 257             }
 258         }
 259     }
 260 }
 261
 262 /*
 263  * tick handler
 264  */
 265 static void exynos4210_rtc_tick(void *opaque)
 266 {
 267     Exynos4210RTCState *s = (Exynos4210RTCState *)opaque;
 268
 269     DPRINTF("TICK IRQ\n");
 270     /* set irq status */
 271     s->reg_intp |= INTP_TICK_ENABLE;
 272     /* raise IRQ */
 273     qemu_irq_raise(s->tick_irq);
 274
 275     /* restart timer */
 276     ptimer_set_count(s->ptimer, s->reg_ticcnt);
 277     ptimer_run(s->ptimer, 1);
 278 }
 279
 280 /*
 281  * 1Hz clock handler
 282  */
 283 static void exynos4210_rtc_1Hz_tick(void *opaque)
 284 {
 285     Exynos4210RTCState *s = (Exynos4210RTCState *)opaque;
 286
 287     rtc_next_second(&s->current_tm);
 288     /* DPRINTF("1Hz tick\n"); */
 289
 290     /* raise IRQ */
 291     if (s->reg_rtcalm & ALARM_INT_ENABLE) {
 292         check_alarm_raise(s);
 293     }
 294
 295     ptimer_set_count(s->ptimer_1Hz, RTC_BASE_FREQ);
 296     ptimer_run(s->ptimer_1Hz, 1);
 297 }
 298
 299 /*
 300  * RTC Read
 301  */
 302 static uint64_t exynos4210_rtc_read(void *opaque, hwaddr offset,
 303         unsigned size)
 304 {
 305     uint32_t value = 0;
 306     Exynos4210RTCState *s = (Exynos4210RTCState *)opaque;
 307
 308     switch (offset) {
 309     case INTP:
 310         value = s->reg_intp;
 311         break;
 312     case RTCCON:
 313         value = s->reg_rtccon;
 314         break;
 315     case TICCNT:
 316         value = s->reg_ticcnt;
 317         break;
 318     case RTCALM:
 319         value = s->reg_rtcalm;
 320         break;
 321     case ALMSEC:
 322         value = s->reg_almsec;
 323         break;
 324     case ALMMIN:
 325         value = s->reg_almmin;
 326         break;
 327     case ALMHOUR:
 328         value = s->reg_almhour;
 329         break;
 330     case ALMDAY:
 331         value = s->reg_almday;
 332         break;
 333     case ALMMON:
 334         value = s->reg_almmon;
 335         break;
 336     case ALMYEAR:
 337         value = s->reg_almyear;
 338         break;
 339
 340     case BCDSEC:
 341         value = (uint32_t)to_bcd((uint8_t)s->current_tm.tm_sec);
 342         break;
 343     case BCDMIN:
 344         value = (uint32_t)to_bcd((uint8_t)s->current_tm.tm_min);
 345         break;
 346     case BCDHOUR:
 347         value = (uint32_t)to_bcd((uint8_t)s->current_tm.tm_hour);
 348         break;
 349     case BCDDAYWEEK:
 350         value = (uint32_t)to_bcd((uint8_t)s->current_tm.tm_wday);
 351         break;
 352     case BCDDAY:
 353         value = (uint32_t)to_bcd((uint8_t)s->current_tm.tm_mday);
 354         break;
 355     case BCDMON:
 356         value = (uint32_t)to_bcd((uint8_t)s->current_tm.tm_mon + 1);
 357         break;
 358     case BCDYEAR:
 359         value = BCD3DIGITS(s->current_tm.tm_year);
 360         break;
 361
 362     case CURTICNT:
 363         s->reg_curticcnt = ptimer_get_count(s->ptimer);
 364         value = s->reg_curticcnt;
 365         break;
 366
 367     default:
 368         fprintf(stderr,
 369                 "[exynos4210.rtc: bad read offset " TARGET_FMT_plx "]\n",
 370                 offset);
 371         break;
 372     }
 373     return value;
 374 }
 375
 376 /*
 377  * RTC Write
 378  */
 379 static void exynos4210_rtc_write(void *opaque, hwaddr offset,
 380         uint64_t value, unsigned size)
 381 {
 382     Exynos4210RTCState *s = (Exynos4210RTCState *)opaque;
 383
 384     switch (offset) {
 385     case INTP:
 386         if (value & INTP_ALM_ENABLE) {
 387             qemu_irq_lower(s->alm_irq);
 388             s->reg_intp &= (~INTP_ALM_ENABLE);
 389         }
 390         if (value & INTP_TICK_ENABLE) {
 391             qemu_irq_lower(s->tick_irq);
 392             s->reg_intp &= (~INTP_TICK_ENABLE);
 393         }
 394         break;
 395     case RTCCON:
 396         if (value & RTC_ENABLE) {
 397             exynos4210_rtc_update_freq(s, value);
 398         }
 399         if ((value & RTC_ENABLE) > (s->reg_rtccon & RTC_ENABLE)) {
 400             /* clock timer */
 401             ptimer_set_count(s->ptimer_1Hz, RTC_BASE_FREQ);
 402             ptimer_run(s->ptimer_1Hz, 1);
 403             DPRINTF("run clock timer\n");
 404         }
 405         if ((value & RTC_ENABLE) < (s->reg_rtccon & RTC_ENABLE)) {
 406             /* tick timer */
 407             ptimer_stop(s->ptimer);
 408             /* clock timer */
 409             ptimer_stop(s->ptimer_1Hz);
 410             DPRINTF("stop all timers\n");
 411         }
 412         if (value & RTC_ENABLE) {
 413             if ((value & TICK_TIMER_ENABLE) >
 414                 (s->reg_rtccon & TICK_TIMER_ENABLE) &&
 415                 (s->reg_ticcnt)) {
 416                 ptimer_set_count(s->ptimer, s->reg_ticcnt);
 417                 ptimer_run(s->ptimer, 1);
 418                 DPRINTF("run tick timer\n");
 419             }
 420             if ((value & TICK_TIMER_ENABLE) <
 421                 (s->reg_rtccon & TICK_TIMER_ENABLE)) {
 422                 ptimer_stop(s->ptimer);
 423             }
 424         }
 425         s->reg_rtccon = value;
 426         break;
 427     case TICCNT:
 428         if (value > TICNT_THRESHHOLD) {
 429             s->reg_ticcnt = value;
 430         } else {
 431             fprintf(stderr,
 432                     "[exynos4210.rtc: bad TICNT value %u ]\n",
 433                     (uint32_t)value);
 434         }
 435         break;
 436
 437     case RTCALM:
 438         s->reg_rtcalm = value;
 439         break;
 440     case ALMSEC:
 441         s->reg_almsec = (value & 0x7f);
 442         break;
 443     case ALMMIN:
 444         s->reg_almmin = (value & 0x7f);
 445         break;
 446     case ALMHOUR:
 447         s->reg_almhour = (value & 0x3f);
 448         break;
 449     case ALMDAY:
 450         s->reg_almday = (value & 0x3f);
 451         break;
 452     case ALMMON:
 453         s->reg_almmon = (value & 0x1f);
 454         break;
 455     case ALMYEAR:
 456         s->reg_almyear = (value & 0x0fff);
 457         break;
 458
 459     case BCDSEC:
 460         if (s->reg_rtccon & RTC_ENABLE) {
 461             s->current_tm.tm_sec = (int)from_bcd((uint8_t)value);
 462         }
 463         break;
 464     case BCDMIN:
 465         if (s->reg_rtccon & RTC_ENABLE) {
 466             s->current_tm.tm_min = (int)from_bcd((uint8_t)value);
 467         }
 468         break;
 469     case BCDHOUR:
 470         if (s->reg_rtccon & RTC_ENABLE) {
 471             s->current_tm.tm_hour = (int)from_bcd((uint8_t)value);
 472         }
 473         break;
 474     case BCDDAYWEEK:
 475         if (s->reg_rtccon & RTC_ENABLE) {
 476             s->current_tm.tm_wday = (int)from_bcd((uint8_t)value);
 477         }
 478         break;
 479     case BCDDAY:
 480         if (s->reg_rtccon & RTC_ENABLE) {
 481             s->current_tm.tm_mday = (int)from_bcd((uint8_t)value);
 482         }
 483         break;
 484     case BCDMON:
 485         if (s->reg_rtccon & RTC_ENABLE) {
 486             s->current_tm.tm_mon = (int)from_bcd((uint8_t)value) - 1;
 487         }
 488         break;
 489     case BCDYEAR:
 490         if (s->reg_rtccon & RTC_ENABLE) {
 491             /* 3 digits */
 492             s->current_tm.tm_year = (int)from_bcd((uint8_t)value) +
 493                     (int)from_bcd((uint8_t)((value >> 8) & 0x0f)) * 100;
 494         }
 495         break;
 496
 497     default:
 498         fprintf(stderr,
 499                 "[exynos4210.rtc: bad write offset " TARGET_FMT_plx "]\n",
 500                 offset);
 501         break;
 502
 503     }
 504 }
 505
 506 /*
 507  * Set default values to timer fields and registers
 508  */
 509 static void exynos4210_rtc_reset(DeviceState *d)
 510 {
 511     Exynos4210RTCState *s = (Exynos4210RTCState *)d;
 512
 513     qemu_get_timedate(&s->current_tm, 0);
 514
 515     DPRINTF("Get time from host: %d-%d-%d %2d:%02d:%02d\n",
 516             s->current_tm.tm_year, s->current_tm.tm_mon, s->current_tm.tm_mday,
 517             s->current_tm.tm_hour, s->current_tm.tm_min, s->current_tm.tm_sec);
 518
 519     s->reg_intp = 0;
 520     s->reg_rtccon = 0;
 521     s->reg_ticcnt = 0;
 522     s->reg_rtcalm = 0;
 523     s->reg_almsec = 0;
 524     s->reg_almmin = 0;
 525     s->reg_almhour = 0;
 526     s->reg_almday = 0;
 527     s->reg_almmon = 0;
 528     s->reg_almyear = 0;
 529
 530     s->reg_curticcnt = 0;
 531
 532     exynos4210_rtc_update_freq(s, s->reg_rtccon);
 533     ptimer_stop(s->ptimer);
 534     ptimer_stop(s->ptimer_1Hz);
 535 }
 536
 537 static const MemoryRegionOps exynos4210_rtc_ops = {
 538     .read = exynos4210_rtc_read,
 539     .write = exynos4210_rtc_write,
 540     .endianness = DEVICE_NATIVE_ENDIAN,
 541 };
 542
 543 /*
 544  * RTC timer initialization
 545  */
 546 static int exynos4210_rtc_init(SysBusDevice *dev)
 547 {
 548     Exynos4210RTCState *s = FROM_SYSBUS(Exynos4210RTCState, dev);
 549     QEMUBH *bh;
 550
 551     bh = qemu_bh_new(exynos4210_rtc_tick, s);
 552     s->ptimer = ptimer_init(bh);
 553     ptimer_set_freq(s->ptimer, RTC_BASE_FREQ);
 554     exynos4210_rtc_update_freq(s, 0);
 555
 556     bh = qemu_bh_new(exynos4210_rtc_1Hz_tick, s);
 557     s->ptimer_1Hz = ptimer_init(bh);
 558     ptimer_set_freq(s->ptimer_1Hz, RTC_BASE_FREQ);
 559
 560     sysbus_init_irq(dev, &s->alm_irq);
 561     sysbus_init_irq(dev, &s->tick_irq);
 562
 563     memory_region_init_io(&s->iomem, &exynos4210_rtc_ops, s, "exynos4210-rtc",
 564             EXYNOS4210_RTC_REG_MEM_SIZE);
 565     sysbus_init_mmio(dev, &s->iomem);
 566
 567     return 0;
 568 }
 569
 570 static void exynos4210_rtc_class_init(ObjectClass *klass, void *data)
 571 {
 572     DeviceClass *dc = DEVICE_CLASS(klass);
 573     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
 574
 575     k->init = exynos4210_rtc_init;
 576     dc->reset = exynos4210_rtc_reset;
 577     dc->vmsd = &vmstate_exynos4210_rtc_state;
 578 }
 579
 580 static const TypeInfo exynos4210_rtc_info = {
 581     .name          = "exynos4210.rtc",
 582     .parent        = TYPE_SYS_BUS_DEVICE,
 583     .instance_size = sizeof(Exynos4210RTCState),
 584     .class_init    = exynos4210_rtc_class_init,
 585 };
 586
 587 static void exynos4210_rtc_register_types(void)
 588 {
 589     type_register_static(&exynos4210_rtc_info);
 590 }
 591
 592 type_init(exynos4210_rtc_register_types)