post/drivers/rtc.c

   1 /*
   2  * (C) Copyright 2002
   3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <common.h>
   9
  10 /*
  11  * RTC test
  12  *
  13  * The Real Time Clock (RTC) operation is verified by this test.
  14  * The following features are verified:
  15  *   o) RTC Power Fault
  16  *      This is verified by analyzing the rtc_get() return status.
  17  *   o) Time uniformity
  18  *      This is verified by reading RTC in polling within
  19  *      a short period of time.
  20  *   o) Passing month boundaries
  21  *      This is checked by setting RTC to a second before
  22  *      a month boundary and reading it after its passing the
  23  *      boundary. The test is performed for both leap- and
  24  *      nonleap-years.
  25  */
  26
  27 #include <post.h>
  28 #include <rtc.h>
  29
  30 #if CONFIG_POST & CONFIG_SYS_POST_RTC
  31
  32 static int rtc_post_skip (ulong * diff)
  33 {
  34         struct rtc_time tm1;
  35         struct rtc_time tm2;
  36         ulong start1;
  37         ulong start2;
  38
  39         rtc_get (&tm1);
  40         start1 = get_timer (0);
  41
  42         while (1) {
  43                 rtc_get (&tm2);
  44                 start2 = get_timer (0);
  45                 if (tm1.tm_sec != tm2.tm_sec)
  46                         break;
  47                 if (start2 - start1 > 1500)
  48                         break;
  49         }
  50
  51         if (tm1.tm_sec != tm2.tm_sec) {
  52                 *diff = start2 - start1;
  53
  54                 return 0;
  55         } else {
  56                 return -1;
  57         }
  58 }
  59
  60 static void rtc_post_restore (struct rtc_time *tm, unsigned int sec)
  61 {
  62         time_t t = mktime (tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_hour,
  63                                            tm->tm_min, tm->tm_sec) + sec;
  64         struct rtc_time ntm;
  65
  66         to_tm (t, &ntm);
  67
  68         rtc_set (&ntm);
  69 }
  70
  71 int rtc_post_test (int flags)
  72 {
  73         ulong diff;
  74         unsigned int i;
  75         struct rtc_time svtm;
  76         static unsigned int daysnl[] =
  77                         { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
  78         static unsigned int daysl[] =
  79                         { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
  80         unsigned int ynl = 1999;
  81         unsigned int yl = 2000;
  82         unsigned int skipped = 0;
  83         int reliable;
  84
  85         /* Time reliability */
  86         reliable = rtc_get (&svtm);
  87
  88         /* Time uniformity */
  89         if (rtc_post_skip (&diff) != 0) {
  90                 post_log ("Timeout while waiting for a new second !\n");
  91
  92                 return -1;
  93         }
  94
  95         for (i = 0; i < 5; i++) {
  96                 if (rtc_post_skip (&diff) != 0) {
  97                         post_log ("Timeout while waiting for a new second !\n");
  98
  99                         return -1;
 100                 }
 101
 102                 if (diff < 950 || diff > 1050) {
 103                         post_log ("Invalid second duration !\n");
 104
 105                         return -1;
 106                 }
 107         }
 108
 109         /* Passing month boundaries */
 110
 111         if (rtc_post_skip (&diff) != 0) {
 112                 post_log ("Timeout while waiting for a new second !\n");
 113
 114                 return -1;
 115         }
 116         rtc_get (&svtm);
 117
 118         for (i = 0; i < 12; i++) {
 119                 time_t t = mktime (ynl, i + 1, daysnl[i], 23, 59, 59);
 120                 struct rtc_time tm;
 121
 122                 to_tm (t, &tm);
 123                 rtc_set (&tm);
 124
 125                 skipped++;
 126                 if (rtc_post_skip (&diff) != 0) {
 127                         rtc_post_restore (&svtm, skipped);
 128                         post_log ("Timeout while waiting for a new second !\n");
 129
 130                         return -1;
 131                 }
 132
 133                 rtc_get (&tm);
 134                 if (tm.tm_mon == i + 1) {
 135                         rtc_post_restore (&svtm, skipped);
 136                         post_log ("Month %d boundary is not passed !\n", i + 1);
 137
 138                         return -1;
 139                 }
 140         }
 141
 142         for (i = 0; i < 12; i++) {
 143                 time_t t = mktime (yl, i + 1, daysl[i], 23, 59, 59);
 144                 struct rtc_time tm;
 145
 146                 to_tm (t, &tm);
 147                 rtc_set (&tm);
 148
 149                 skipped++;
 150                 if (rtc_post_skip (&diff) != 0) {
 151                         rtc_post_restore (&svtm, skipped);
 152                         post_log ("Timeout while waiting for a new second !\n");
 153
 154                         return -1;
 155                 }
 156
 157                 rtc_get (&tm);
 158                 if (tm.tm_mon == i + 1) {
 159                         rtc_post_restore (&svtm, skipped);
 160                         post_log ("Month %d boundary is not passed !\n", i + 1);
 161
 162                         return -1;
 163                 }
 164         }
 165         rtc_post_restore (&svtm, skipped);
 166
 167         /* If come here, then RTC operates correcty, check the correctness
 168          * of the time it reports.
 169          */
 170         if (reliable < 0) {
 171                 post_log ("RTC Time is not reliable! Power fault? \n");
 172
 173                 return -1;
 174         }
 175
 176         return 0;
 177 }
 178
 179 #endif /* CONFIG_POST & CONFIG_SYS_POST_RTC */