tests/rtc-test.c

   1 /*
   2  * QTest testcase for the MC146818 real-time clock
   3  *
   4  * Copyright IBM, Corp. 2012
   5  *
   6  * Authors:
   7  *  Anthony Liguori   <aliguori@us.ibm.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  10  * See the COPYING file in the top-level directory.
  11  *
  12  */
  13
  14 #include "qemu/osdep.h"
  15
  16 #include "libqtest.h"
  17 #include "qemu/timer.h"
  18 #include "hw/timer/mc146818rtc_regs.h"
  19
  20 static uint8_t base = 0x70;
  21
  22 static int bcd2dec(int value)
  23 {
  24     return (((value >> 4) & 0x0F) * 10) + (value & 0x0F);
  25 }
  26
  27 static uint8_t cmos_read(uint8_t reg)
  28 {
  29     outb(base + 0, reg);
  30     return inb(base + 1);
  31 }
  32
  33 static void cmos_write(uint8_t reg, uint8_t val)
  34 {
  35     outb(base + 0, reg);
  36     outb(base + 1, val);
  37 }
  38
  39 static int tm_cmp(struct tm *lhs, struct tm *rhs)
  40 {
  41     time_t a, b;
  42     struct tm d1, d2;
  43
  44     memcpy(&d1, lhs, sizeof(d1));
  45     memcpy(&d2, rhs, sizeof(d2));
  46
  47     a = mktime(&d1);
  48     b = mktime(&d2);
  49
  50     if (a < b) {
  51         return -1;
  52     } else if (a > b) {
  53         return 1;
  54     }
  55
  56     return 0;
  57 }
  58
  59 #if 0
  60 static void print_tm(struct tm *tm)
  61 {
  62     printf("%04d-%02d-%02d %02d:%02d:%02d\n",
  63            tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
  64            tm->tm_hour, tm->tm_min, tm->tm_sec, tm->tm_gmtoff);
  65 }
  66 #endif
  67
  68 static void cmos_get_date_time(struct tm *date)
  69 {
  70     int base_year = 2000, hour_offset;
  71     int sec, min, hour, mday, mon, year;
  72     time_t ts;
  73     struct tm dummy;
  74
  75     sec = cmos_read(RTC_SECONDS);
  76     min = cmos_read(RTC_MINUTES);
  77     hour = cmos_read(RTC_HOURS);
  78     mday = cmos_read(RTC_DAY_OF_MONTH);
  79     mon = cmos_read(RTC_MONTH);
  80     year = cmos_read(RTC_YEAR);
  81
  82     if ((cmos_read(RTC_REG_B) & REG_B_DM) == 0) {
  83         sec = bcd2dec(sec);
  84         min = bcd2dec(min);
  85         hour = bcd2dec(hour);
  86         mday = bcd2dec(mday);
  87         mon = bcd2dec(mon);
  88         year = bcd2dec(year);
  89         hour_offset = 80;
  90     } else {
  91         hour_offset = 0x80;
  92     }
  93
  94     if ((cmos_read(0x0B) & REG_B_24H) == 0) {
  95         if (hour >= hour_offset) {
  96             hour -= hour_offset;
  97             hour += 12;
  98         }
  99     }
 100
 101     ts = time(NULL);
 102     localtime_r(&ts, &dummy);
 103
 104     date->tm_isdst = dummy.tm_isdst;
 105     date->tm_sec = sec;
 106     date->tm_min = min;
 107     date->tm_hour = hour;
 108     date->tm_mday = mday;
 109     date->tm_mon = mon - 1;
 110     date->tm_year = base_year + year - 1900;
 111 #ifndef __sun__
 112     date->tm_gmtoff = 0;
 113 #endif
 114
 115     ts = mktime(date);
 116 }
 117
 118 static void check_time(int wiggle)
 119 {
 120     struct tm start, date[4], end;
 121     struct tm *datep;
 122     time_t ts;
 123
 124     /*
 125      * This check assumes a few things.  First, we cannot guarantee that we get
 126      * a consistent reading from the wall clock because we may hit an edge of
 127      * the clock while reading.  To work around this, we read four clock readings
 128      * such that at least two of them should match.  We need to assume that one
 129      * reading is corrupt so we need four readings to ensure that we have at
 130      * least two consecutive identical readings
 131      *
 132      * It's also possible that we'll cross an edge reading the host clock so
 133      * simply check to make sure that the clock reading is within the period of
 134      * when we expect it to be.
 135      */
 136
 137     ts = time(NULL);
 138     gmtime_r(&ts, &start);
 139
 140     cmos_get_date_time(&date[0]);
 141     cmos_get_date_time(&date[1]);
 142     cmos_get_date_time(&date[2]);
 143     cmos_get_date_time(&date[3]);
 144
 145     ts = time(NULL);
 146     gmtime_r(&ts, &end);
 147
 148     if (tm_cmp(&date[0], &date[1]) == 0) {
 149         datep = &date[0];
 150     } else if (tm_cmp(&date[1], &date[2]) == 0) {
 151         datep = &date[1];
 152     } else if (tm_cmp(&date[2], &date[3]) == 0) {
 153         datep = &date[2];
 154     } else {
 155         g_assert_not_reached();
 156     }
 157
 158     if (!(tm_cmp(&start, datep) <= 0 && tm_cmp(datep, &end) <= 0)) {
 159         long t, s;
 160
 161         start.tm_isdst = datep->tm_isdst;
 162
 163         t = (long)mktime(datep);
 164         s = (long)mktime(&start);
 165         if (t < s) {
 166             g_test_message("RTC is %ld second(s) behind wall-clock\n", (s - t));
 167         } else {
 168             g_test_message("RTC is %ld second(s) ahead of wall-clock\n", (t - s));
 169         }
 170
 171         g_assert_cmpint(ABS(t - s), <=, wiggle);
 172     }
 173 }
 174
 175 static int wiggle = 2;
 176
 177 static void set_year_20xx(void)
 178 {
 179     /* Set BCD mode */
 180     cmos_write(RTC_REG_B, REG_B_24H);
 181     cmos_write(RTC_REG_A, 0x76);
 182     cmos_write(RTC_YEAR, 0x11);
 183     cmos_write(RTC_CENTURY, 0x20);
 184     cmos_write(RTC_MONTH, 0x02);
 185     cmos_write(RTC_DAY_OF_MONTH, 0x02);
 186     cmos_write(RTC_HOURS, 0x02);
 187     cmos_write(RTC_MINUTES, 0x04);
 188     cmos_write(RTC_SECONDS, 0x58);
 189     cmos_write(RTC_REG_A, 0x26);
 190
 191     g_assert_cmpint(cmos_read(RTC_HOURS), ==, 0x02);
 192     g_assert_cmpint(cmos_read(RTC_MINUTES), ==, 0x04);
 193     g_assert_cmpint(cmos_read(RTC_SECONDS), >=, 0x58);
 194     g_assert_cmpint(cmos_read(RTC_DAY_OF_MONTH), ==, 0x02);
 195     g_assert_cmpint(cmos_read(RTC_MONTH), ==, 0x02);
 196     g_assert_cmpint(cmos_read(RTC_YEAR), ==, 0x11);
 197     g_assert_cmpint(cmos_read(RTC_CENTURY), ==, 0x20);
 198
 199     if (sizeof(time_t) == 4) {
 200         return;
 201     }
 202
 203     /* Set a date in 2080 to ensure there is no year-2038 overflow.  */
 204     cmos_write(RTC_REG_A, 0x76);
 205     cmos_write(RTC_YEAR, 0x80);
 206     cmos_write(RTC_REG_A, 0x26);
 207
 208     g_assert_cmpint(cmos_read(RTC_HOURS), ==, 0x02);
 209     g_assert_cmpint(cmos_read(RTC_MINUTES), ==, 0x04);
 210     g_assert_cmpint(cmos_read(RTC_SECONDS), >=, 0x58);
 211     g_assert_cmpint(cmos_read(RTC_DAY_OF_MONTH), ==, 0x02);
 212     g_assert_cmpint(cmos_read(RTC_MONTH), ==, 0x02);
 213     g_assert_cmpint(cmos_read(RTC_YEAR), ==, 0x80);
 214     g_assert_cmpint(cmos_read(RTC_CENTURY), ==, 0x20);
 215
 216     cmos_write(RTC_REG_A, 0x76);
 217     cmos_write(RTC_YEAR, 0x11);
 218     cmos_write(RTC_REG_A, 0x26);
 219
 220     g_assert_cmpint(cmos_read(RTC_HOURS), ==, 0x02);
 221     g_assert_cmpint(cmos_read(RTC_MINUTES), ==, 0x04);
 222     g_assert_cmpint(cmos_read(RTC_SECONDS), >=, 0x58);
 223     g_assert_cmpint(cmos_read(RTC_DAY_OF_MONTH), ==, 0x02);
 224     g_assert_cmpint(cmos_read(RTC_MONTH), ==, 0x02);
 225     g_assert_cmpint(cmos_read(RTC_YEAR), ==, 0x11);
 226     g_assert_cmpint(cmos_read(RTC_CENTURY), ==, 0x20);
 227 }
 228
 229 static void set_year_1980(void)
 230 {
 231     /* Set BCD mode */
 232     cmos_write(RTC_REG_B, REG_B_24H);
 233     cmos_write(RTC_REG_A, 0x76);
 234     cmos_write(RTC_YEAR, 0x80);
 235     cmos_write(RTC_CENTURY, 0x19);
 236     cmos_write(RTC_MONTH, 0x02);
 237     cmos_write(RTC_DAY_OF_MONTH, 0x02);
 238     cmos_write(RTC_HOURS, 0x02);
 239     cmos_write(RTC_MINUTES, 0x04);
 240     cmos_write(RTC_SECONDS, 0x58);
 241     cmos_write(RTC_REG_A, 0x26);
 242
 243     g_assert_cmpint(cmos_read(RTC_HOURS), ==, 0x02);
 244     g_assert_cmpint(cmos_read(RTC_MINUTES), ==, 0x04);
 245     g_assert_cmpint(cmos_read(RTC_SECONDS), >=, 0x58);
 246     g_assert_cmpint(cmos_read(RTC_DAY_OF_MONTH), ==, 0x02);
 247     g_assert_cmpint(cmos_read(RTC_MONTH), ==, 0x02);
 248     g_assert_cmpint(cmos_read(RTC_YEAR), ==, 0x80);
 249     g_assert_cmpint(cmos_read(RTC_CENTURY), ==, 0x19);
 250 }
 251
 252 static void bcd_check_time(void)
 253 {
 254     /* Set BCD mode */
 255     cmos_write(RTC_REG_B, REG_B_24H);
 256     check_time(wiggle);
 257 }
 258
 259 static void dec_check_time(void)
 260 {
 261     /* Set DEC mode */
 262     cmos_write(RTC_REG_B, REG_B_24H | REG_B_DM);
 263     check_time(wiggle);
 264 }
 265
 266 static void alarm_time(void)
 267 {
 268     struct tm now;
 269     time_t ts;
 270     int i;
 271
 272     ts = time(NULL);
 273     gmtime_r(&ts, &now);
 274
 275     /* set DEC mode */
 276     cmos_write(RTC_REG_B, REG_B_24H | REG_B_DM);
 277
 278     g_assert(!get_irq(RTC_ISA_IRQ));
 279     cmos_read(RTC_REG_C);
 280
 281     now.tm_sec = (now.tm_sec + 2) % 60;
 282     cmos_write(RTC_SECONDS_ALARM, now.tm_sec);
 283     cmos_write(RTC_MINUTES_ALARM, RTC_ALARM_DONT_CARE);
 284     cmos_write(RTC_HOURS_ALARM, RTC_ALARM_DONT_CARE);
 285     cmos_write(RTC_REG_B, cmos_read(RTC_REG_B) | REG_B_AIE);
 286
 287     for (i = 0; i < 2 + wiggle; i++) {
 288         if (get_irq(RTC_ISA_IRQ)) {
 289             break;
 290         }
 291
 292         clock_step(1000000000);
 293     }
 294
 295     g_assert(get_irq(RTC_ISA_IRQ));
 296     g_assert((cmos_read(RTC_REG_C) & REG_C_AF) != 0);
 297     g_assert(cmos_read(RTC_REG_C) == 0);
 298 }
 299
 300 static void set_time(int mode, int h, int m, int s)
 301 {
 302     /* set BCD 12 hour mode */
 303     cmos_write(RTC_REG_B, mode);
 304
 305     cmos_write(RTC_REG_A, 0x76);
 306     cmos_write(RTC_HOURS, h);
 307     cmos_write(RTC_MINUTES, m);
 308     cmos_write(RTC_SECONDS, s);
 309     cmos_write(RTC_REG_A, 0x26);
 310 }
 311
 312 #define assert_time(h, m, s) \
 313     do { \
 314         g_assert_cmpint(cmos_read(RTC_HOURS), ==, h); \
 315         g_assert_cmpint(cmos_read(RTC_MINUTES), ==, m); \
 316         g_assert_cmpint(cmos_read(RTC_SECONDS), ==, s); \
 317     } while(0)
 318
 319 static void basic_12h_bcd(void)
 320 {
 321     /* set BCD 12 hour mode */
 322     set_time(0, 0x81, 0x59, 0x00);
 323     clock_step(1000000000LL);
 324     assert_time(0x81, 0x59, 0x01);
 325     clock_step(59000000000LL);
 326     assert_time(0x82, 0x00, 0x00);
 327
 328     /* test BCD wraparound */
 329     set_time(0, 0x09, 0x59, 0x59);
 330     clock_step(60000000000LL);
 331     assert_time(0x10, 0x00, 0x59);
 332
 333     /* 12 AM -> 1 AM */
 334     set_time(0, 0x12, 0x59, 0x59);
 335     clock_step(1000000000LL);
 336     assert_time(0x01, 0x00, 0x00);
 337
 338     /* 12 PM -> 1 PM */
 339     set_time(0, 0x92, 0x59, 0x59);
 340     clock_step(1000000000LL);
 341     assert_time(0x81, 0x00, 0x00);
 342
 343     /* 11 AM -> 12 PM */
 344     set_time(0, 0x11, 0x59, 0x59);
 345     clock_step(1000000000LL);
 346     assert_time(0x92, 0x00, 0x00);
 347     /* TODO: test day wraparound */
 348
 349     /* 11 PM -> 12 AM */
 350     set_time(0, 0x91, 0x59, 0x59);
 351     clock_step(1000000000LL);
 352     assert_time(0x12, 0x00, 0x00);
 353     /* TODO: test day wraparound */
 354 }
 355
 356 static void basic_12h_dec(void)
 357 {
 358     /* set decimal 12 hour mode */
 359     set_time(REG_B_DM, 0x81, 59, 0);
 360     clock_step(1000000000LL);
 361     assert_time(0x81, 59, 1);
 362     clock_step(59000000000LL);
 363     assert_time(0x82, 0, 0);
 364
 365     /* 12 PM -> 1 PM */
 366     set_time(REG_B_DM, 0x8c, 59, 59);
 367     clock_step(1000000000LL);
 368     assert_time(0x81, 0, 0);
 369
 370     /* 12 AM -> 1 AM */
 371     set_time(REG_B_DM, 0x0c, 59, 59);
 372     clock_step(1000000000LL);
 373     assert_time(0x01, 0, 0);
 374
 375     /* 11 AM -> 12 PM */
 376     set_time(REG_B_DM, 0x0b, 59, 59);
 377     clock_step(1000000000LL);
 378     assert_time(0x8c, 0, 0);
 379
 380     /* 11 PM -> 12 AM */
 381     set_time(REG_B_DM, 0x8b, 59, 59);
 382     clock_step(1000000000LL);
 383     assert_time(0x0c, 0, 0);
 384     /* TODO: test day wraparound */
 385 }
 386
 387 static void basic_24h_bcd(void)
 388 {
 389     /* set BCD 24 hour mode */
 390     set_time(REG_B_24H, 0x09, 0x59, 0x00);
 391     clock_step(1000000000LL);
 392     assert_time(0x09, 0x59, 0x01);
 393     clock_step(59000000000LL);
 394     assert_time(0x10, 0x00, 0x00);
 395
 396     /* test BCD wraparound */
 397     set_time(REG_B_24H, 0x09, 0x59, 0x00);
 398     clock_step(60000000000LL);
 399     assert_time(0x10, 0x00, 0x00);
 400
 401     /* TODO: test day wraparound */
 402     set_time(REG_B_24H, 0x23, 0x59, 0x00);
 403     clock_step(60000000000LL);
 404     assert_time(0x00, 0x00, 0x00);
 405 }
 406
 407 static void basic_24h_dec(void)
 408 {
 409     /* set decimal 24 hour mode */
 410     set_time(REG_B_24H | REG_B_DM, 9, 59, 0);
 411     clock_step(1000000000LL);
 412     assert_time(9, 59, 1);
 413     clock_step(59000000000LL);
 414     assert_time(10, 0, 0);
 415
 416     /* test BCD wraparound */
 417     set_time(REG_B_24H | REG_B_DM, 9, 59, 0);
 418     clock_step(60000000000LL);
 419     assert_time(10, 0, 0);
 420
 421     /* TODO: test day wraparound */
 422     set_time(REG_B_24H | REG_B_DM, 23, 59, 0);
 423     clock_step(60000000000LL);
 424     assert_time(0, 0, 0);
 425 }
 426
 427 static void am_pm_alarm(void)
 428 {
 429     cmos_write(RTC_MINUTES_ALARM, 0xC0);
 430     cmos_write(RTC_SECONDS_ALARM, 0xC0);
 431
 432     /* set BCD 12 hour mode */
 433     cmos_write(RTC_REG_B, 0);
 434
 435     /* Set time and alarm hour.  */
 436     cmos_write(RTC_REG_A, 0x76);
 437     cmos_write(RTC_HOURS_ALARM, 0x82);
 438     cmos_write(RTC_HOURS, 0x81);
 439     cmos_write(RTC_MINUTES, 0x59);
 440     cmos_write(RTC_SECONDS, 0x00);
 441     cmos_read(RTC_REG_C);
 442     cmos_write(RTC_REG_A, 0x26);
 443
 444     /* Check that alarm triggers when AM/PM is set.  */
 445     clock_step(60000000000LL);
 446     g_assert(cmos_read(RTC_HOURS) == 0x82);
 447     g_assert((cmos_read(RTC_REG_C) & REG_C_AF) != 0);
 448
 449     /*
 450      * Each of the following two tests takes over 60 seconds due to the time
 451      * needed to report the PIT interrupts.  Unfortunately, our PIT device
 452      * model keeps counting even when GATE=0, so we cannot simply disable
 453      * it in main().
 454      */
 455     if (g_test_quick()) {
 456         return;
 457     }
 458
 459     /* set DEC 12 hour mode */
 460     cmos_write(RTC_REG_B, REG_B_DM);
 461
 462     /* Set time and alarm hour.  */
 463     cmos_write(RTC_REG_A, 0x76);
 464     cmos_write(RTC_HOURS_ALARM, 0x82);
 465     cmos_write(RTC_HOURS, 3);
 466     cmos_write(RTC_MINUTES, 0);
 467     cmos_write(RTC_SECONDS, 0);
 468     cmos_read(RTC_REG_C);
 469     cmos_write(RTC_REG_A, 0x26);
 470
 471     /* Check that alarm triggers.  */
 472     clock_step(3600 * 11 * 1000000000LL);
 473     g_assert(cmos_read(RTC_HOURS) == 0x82);
 474     g_assert((cmos_read(RTC_REG_C) & REG_C_AF) != 0);
 475
 476     /* Same as above, with inverted HOURS and HOURS_ALARM.  */
 477     cmos_write(RTC_REG_A, 0x76);
 478     cmos_write(RTC_HOURS_ALARM, 2);
 479     cmos_write(RTC_HOURS, 3);
 480     cmos_write(RTC_MINUTES, 0);
 481     cmos_write(RTC_SECONDS, 0);
 482     cmos_read(RTC_REG_C);
 483     cmos_write(RTC_REG_A, 0x26);
 484
 485     /* Check that alarm does not trigger if hours differ only by AM/PM.  */
 486     clock_step(3600 * 11 * 1000000000LL);
 487     g_assert(cmos_read(RTC_HOURS) == 0x82);
 488     g_assert((cmos_read(RTC_REG_C) & REG_C_AF) == 0);
 489 }
 490
 491 /* success if no crash or abort */
 492 static void fuzz_registers(void)
 493 {
 494     unsigned int i;
 495
 496     for (i = 0; i < 1000; i++) {
 497         uint8_t reg, val;
 498
 499         reg = (uint8_t)g_test_rand_int_range(0, 16);
 500         val = (uint8_t)g_test_rand_int_range(0, 256);
 501
 502         cmos_write(reg, val);
 503         cmos_read(reg);
 504     }
 505 }
 506
 507 static void register_b_set_flag(void)
 508 {
 509     /* Enable binary-coded decimal (BCD) mode and SET flag in Register B*/
 510     cmos_write(RTC_REG_B, REG_B_24H | REG_B_SET);
 511
 512     cmos_write(RTC_REG_A, 0x76);
 513     cmos_write(RTC_YEAR, 0x11);
 514     cmos_write(RTC_CENTURY, 0x20);
 515     cmos_write(RTC_MONTH, 0x02);
 516     cmos_write(RTC_DAY_OF_MONTH, 0x02);
 517     cmos_write(RTC_HOURS, 0x02);
 518     cmos_write(RTC_MINUTES, 0x04);
 519     cmos_write(RTC_SECONDS, 0x58);
 520     cmos_write(RTC_REG_A, 0x26);
 521
 522     /* Since SET flag is still enabled, these are equality checks. */
 523     g_assert_cmpint(cmos_read(RTC_HOURS), ==, 0x02);
 524     g_assert_cmpint(cmos_read(RTC_MINUTES), ==, 0x04);
 525     g_assert_cmpint(cmos_read(RTC_SECONDS), ==, 0x58);
 526     g_assert_cmpint(cmos_read(RTC_DAY_OF_MONTH), ==, 0x02);
 527     g_assert_cmpint(cmos_read(RTC_MONTH), ==, 0x02);
 528     g_assert_cmpint(cmos_read(RTC_YEAR), ==, 0x11);
 529     g_assert_cmpint(cmos_read(RTC_CENTURY), ==, 0x20);
 530
 531     /* Disable SET flag in Register B */
 532     cmos_write(RTC_REG_B, cmos_read(RTC_REG_B) & ~REG_B_SET);
 533
 534     g_assert_cmpint(cmos_read(RTC_HOURS), ==, 0x02);
 535     g_assert_cmpint(cmos_read(RTC_MINUTES), ==, 0x04);
 536
 537     /* Since SET flag is disabled, this is an inequality check.
 538      * We (reasonably) assume that no (sexagesimal) overflow occurs. */
 539     g_assert_cmpint(cmos_read(RTC_SECONDS), >=, 0x58);
 540     g_assert_cmpint(cmos_read(RTC_DAY_OF_MONTH), ==, 0x02);
 541     g_assert_cmpint(cmos_read(RTC_MONTH), ==, 0x02);
 542     g_assert_cmpint(cmos_read(RTC_YEAR), ==, 0x11);
 543     g_assert_cmpint(cmos_read(RTC_CENTURY), ==, 0x20);
 544 }
 545
 546 #define RTC_PERIOD_CODE1    13   /* 8 Hz */
 547 #define RTC_PERIOD_CODE2    15   /* 2 Hz */
 548
 549 #define RTC_PERIOD_TEST_NR  50
 550
 551 static uint64_t wait_periodic_interrupt(uint64_t real_time)
 552 {
 553     while (!get_irq(RTC_ISA_IRQ)) {
 554         real_time = clock_step_next();
 555     }
 556
 557     g_assert((cmos_read(RTC_REG_C) & REG_C_PF) != 0);
 558     return real_time;
 559 }
 560
 561 static void periodic_timer(void)
 562 {
 563     int i;
 564     uint64_t period_clocks, period_time, start_time, real_time;
 565
 566     /* disable all interrupts. */
 567     cmos_write(RTC_REG_B, cmos_read(RTC_REG_B) &
 568                                    ~(REG_B_PIE | REG_B_AIE | REG_B_UIE));
 569     cmos_write(RTC_REG_A, RTC_PERIOD_CODE1);
 570     /* enable periodic interrupt after properly configure the period. */
 571     cmos_write(RTC_REG_B, cmos_read(RTC_REG_B) | REG_B_PIE);
 572
 573     start_time = real_time = clock_step_next();
 574
 575     for (i = 0; i < RTC_PERIOD_TEST_NR; i++) {
 576         cmos_write(RTC_REG_A, RTC_PERIOD_CODE1);
 577         real_time = wait_periodic_interrupt(real_time);
 578         cmos_write(RTC_REG_A, RTC_PERIOD_CODE2);
 579         real_time = wait_periodic_interrupt(real_time);
 580     }
 581
 582     period_clocks = periodic_period_to_clock(RTC_PERIOD_CODE1) +
 583                        periodic_period_to_clock(RTC_PERIOD_CODE2);
 584     period_clocks *= RTC_PERIOD_TEST_NR;
 585     period_time = periodic_clock_to_ns(period_clocks);
 586
 587     real_time -= start_time;
 588     g_assert_cmpint(ABS((int64_t)(real_time - period_time)), <=,
 589                     NANOSECONDS_PER_SECOND * 0.5);
 590 }
 591
 592 int main(int argc, char **argv)
 593 {
 594     QTestState *s = NULL;
 595     int ret;
 596
 597     g_test_init(&argc, &argv, NULL);
 598
 599     s = qtest_start("-rtc clock=vm");
 600     qtest_irq_intercept_in(s, "ioapic");
 601
 602     qtest_add_func("/rtc/check-time/bcd", bcd_check_time);
 603     qtest_add_func("/rtc/check-time/dec", dec_check_time);
 604     qtest_add_func("/rtc/alarm/interrupt", alarm_time);
 605     qtest_add_func("/rtc/alarm/am-pm", am_pm_alarm);
 606     qtest_add_func("/rtc/basic/dec-24h", basic_24h_dec);
 607     qtest_add_func("/rtc/basic/bcd-24h", basic_24h_bcd);
 608     qtest_add_func("/rtc/basic/dec-12h", basic_12h_dec);
 609     qtest_add_func("/rtc/basic/bcd-12h", basic_12h_bcd);
 610     qtest_add_func("/rtc/set-year/20xx", set_year_20xx);
 611     qtest_add_func("/rtc/set-year/1980", set_year_1980);
 612     qtest_add_func("/rtc/misc/register_b_set_flag", register_b_set_flag);
 613     qtest_add_func("/rtc/misc/fuzz-registers", fuzz_registers);
 614     qtest_add_func("/rtc/periodic/interrupt", periodic_timer);
 615
 616     ret = g_test_run();
 617
 618     if (s) {
 619         qtest_quit(s);
 620     }
 621
 622     return ret;
 623 }