xref: /openbmc/u-boot/post/drivers/rtc.c (revision dd580801)
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 */
180