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 #include "libqtest.h"
  14 #include "hw/mc146818rtc_regs.h"
  15
  16 #include <glib.h>
  17 #include <stdio.h>
  18 #include <string.h>
  19 #include <stdlib.h>
  20 #include <unistd.h>
  21
  22 static uint8_t base = 0x70;
  23
  24 static int bcd2dec(int value)
  25 {
  26     return (((value >> 4) & 0x0F) * 10) + (value & 0x0F);
  27 }
  28
  29 static int dec2bcd(int value)
  30 {
  31     return ((value / 10) << 4) | (value % 10);
  32 }
  33
  34 static uint8_t cmos_read(uint8_t reg)
  35 {
  36     outb(base + 0, reg);
  37     return inb(base + 1);
  38 }
  39
  40 static void cmos_write(uint8_t reg, uint8_t val)
  41 {
  42     outb(base + 0, reg);
  43     outb(base + 1, val);
  44 }
  45
  46 static int tm_cmp(struct tm *lhs, struct tm *rhs)
  47 {
  48     time_t a, b;
  49     struct tm d1, d2;
  50
  51     memcpy(&d1, lhs, sizeof(d1));
  52     memcpy(&d2, rhs, sizeof(d2));
  53
  54     a = mktime(&d1);
  55     b = mktime(&d2);
  56
  57     if (a < b) {
  58         return -1;
  59     } else if (a > b) {
  60         return 1;
  61     }
  62
  63     return 0;
  64 }
  65
  66 #if 0
  67 static void print_tm(struct tm *tm)
  68 {
  69     printf("%04d-%02d-%02d %02d:%02d:%02d\n",
  70            tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
  71            tm->tm_hour, tm->tm_min, tm->tm_sec, tm->tm_gmtoff);
  72 }
  73 #endif
  74
  75 static void cmos_get_date_time(struct tm *date)
  76 {
  77     int base_year = 2000, hour_offset;
  78     int sec, min, hour, mday, mon, year;
  79     time_t ts;
  80     struct tm dummy;
  81
  82     sec = cmos_read(RTC_SECONDS);
  83     min = cmos_read(RTC_MINUTES);
  84     hour = cmos_read(RTC_HOURS);
  85     mday = cmos_read(RTC_DAY_OF_MONTH);
  86     mon = cmos_read(RTC_MONTH);
  87     year = cmos_read(RTC_YEAR);
  88
  89     if ((cmos_read(RTC_REG_B) & REG_B_DM) == 0) {
  90         sec = bcd2dec(sec);
  91         min = bcd2dec(min);
  92         hour = bcd2dec(hour);
  93         mday = bcd2dec(mday);
  94         mon = bcd2dec(mon);
  95         year = bcd2dec(year);
  96         hour_offset = 80;
  97     } else {
  98         hour_offset = 0x80;
  99     }
 100
 101     if ((cmos_read(0x0B) & REG_B_24H) == 0) {
 102         if (hour >= hour_offset) {
 103             hour -= hour_offset;
 104             hour += 12;
 105         }
 106     }
 107
 108     ts = time(NULL);
 109     localtime_r(&ts, &dummy);
 110
 111     date->tm_isdst = dummy.tm_isdst;
 112     date->tm_sec = sec;
 113     date->tm_min = min;
 114     date->tm_hour = hour;
 115     date->tm_mday = mday;
 116     date->tm_mon = mon - 1;
 117     date->tm_year = base_year + year - 1900;
 118     date->tm_gmtoff = 0;
 119
 120     ts = mktime(date);
 121 }
 122
 123 static void check_time(int wiggle)
 124 {
 125     struct tm start, date[4], end;
 126     struct tm *datep;
 127     time_t ts;
 128
 129     /*
 130      * This check assumes a few things.  First, we cannot guarantee that we get
 131      * a consistent reading from the wall clock because we may hit an edge of
 132      * the clock while reading.  To work around this, we read four clock readings
 133      * such that at least two of them should match.  We need to assume that one
 134      * reading is corrupt so we need four readings to ensure that we have at
 135      * least two consecutive identical readings
 136      *
 137      * It's also possible that we'll cross an edge reading the host clock so
 138      * simply check to make sure that the clock reading is within the period of
 139      * when we expect it to be.
 140      */
 141
 142     ts = time(NULL);
 143     gmtime_r(&ts, &start);
 144
 145     cmos_get_date_time(&date[0]);
 146     cmos_get_date_time(&date[1]);
 147     cmos_get_date_time(&date[2]);
 148     cmos_get_date_time(&date[3]);
 149
 150     ts = time(NULL);
 151     gmtime_r(&ts, &end);
 152
 153     if (tm_cmp(&date[0], &date[1]) == 0) {
 154         datep = &date[0];
 155     } else if (tm_cmp(&date[1], &date[2]) == 0) {
 156         datep = &date[1];
 157     } else if (tm_cmp(&date[2], &date[3]) == 0) {
 158         datep = &date[2];
 159     } else {
 160         g_assert_not_reached();
 161     }
 162
 163     if (!(tm_cmp(&start, datep) <= 0 && tm_cmp(datep, &end) <= 0)) {
 164         long t, s;
 165
 166         start.tm_isdst = datep->tm_isdst;
 167
 168         t = (long)mktime(datep);
 169         s = (long)mktime(&start);
 170         if (t < s) {
 171             g_test_message("RTC is %ld second(s) behind wall-clock\n", (s - t));
 172         } else {
 173             g_test_message("RTC is %ld second(s) ahead of wall-clock\n", (t - s));
 174         }
 175
 176         g_assert_cmpint(ABS(t - s), <=, wiggle);
 177     }
 178 }
 179
 180 static int wiggle = 2;
 181
 182 static void bcd_check_time(void)
 183 {
 184     /* Set BCD mode */
 185     cmos_write(RTC_REG_B, cmos_read(RTC_REG_B) & ~REG_B_DM);
 186     check_time(wiggle);
 187 }
 188
 189 static void dec_check_time(void)
 190 {
 191     /* Set DEC mode */
 192     cmos_write(RTC_REG_B, cmos_read(RTC_REG_B) | REG_B_DM);
 193     check_time(wiggle);
 194 }
 195
 196 static void set_alarm_time(struct tm *tm)
 197 {
 198     int sec;
 199
 200     sec = tm->tm_sec;
 201
 202     if ((cmos_read(RTC_REG_B) & REG_B_DM) == 0) {
 203         sec = dec2bcd(sec);
 204     }
 205
 206     cmos_write(RTC_SECONDS_ALARM, sec);
 207     cmos_write(RTC_MINUTES_ALARM, RTC_ALARM_DONT_CARE);
 208     cmos_write(RTC_HOURS_ALARM, RTC_ALARM_DONT_CARE);
 209 }
 210
 211 static void alarm_time(void)
 212 {
 213     struct tm now;
 214     time_t ts;
 215     int i;
 216
 217     ts = time(NULL);
 218     gmtime_r(&ts, &now);
 219
 220     /* set DEC mode */
 221     cmos_write(RTC_REG_B, cmos_read(RTC_REG_B) | REG_B_DM);
 222
 223     g_assert(!get_irq(RTC_ISA_IRQ));
 224     cmos_read(RTC_REG_C);
 225
 226     now.tm_sec = (now.tm_sec + 2) % 60;
 227     set_alarm_time(&now);
 228     cmos_write(RTC_REG_B, cmos_read(RTC_REG_B) | REG_B_AIE);
 229
 230     for (i = 0; i < 2 + wiggle; i++) {
 231         if (get_irq(RTC_ISA_IRQ)) {
 232             break;
 233         }
 234
 235         clock_step(1000000000);
 236     }
 237
 238     g_assert(get_irq(RTC_ISA_IRQ));
 239     g_assert((cmos_read(RTC_REG_C) & REG_C_AF) != 0);
 240     g_assert(cmos_read(RTC_REG_C) == 0);
 241 }
 242
 243 /* success if no crash or abort */
 244 static void fuzz_registers(void)
 245 {
 246     unsigned int i;
 247
 248     for (i = 0; i < 1000; i++) {
 249         uint8_t reg, val;
 250
 251         reg = (uint8_t)g_test_rand_int_range(0, 16);
 252         val = (uint8_t)g_test_rand_int_range(0, 256);
 253
 254         cmos_write(reg, val);
 255         cmos_read(reg);
 256     }
 257 }
 258
 259 int main(int argc, char **argv)
 260 {
 261     QTestState *s = NULL;
 262     int ret;
 263
 264     g_test_init(&argc, &argv, NULL);
 265
 266     s = qtest_start("-display none -rtc clock=vm");
 267     qtest_irq_intercept_in(s, "ioapic");
 268
 269     qtest_add_func("/rtc/bcd/check-time", bcd_check_time);
 270     qtest_add_func("/rtc/dec/check-time", dec_check_time);
 271     qtest_add_func("/rtc/alarm-time", alarm_time);
 272     qtest_add_func("/rtc/fuzz-registers", fuzz_registers);
 273     ret = g_test_run();
 274
 275     if (s) {
 276         qtest_quit(s);
 277     }
 278
 279     return ret;
 280 }