xref: /openbmc/u-boot/post/drivers/rtc.c (revision 15855700)
1 /*
2  * (C) Copyright 2002
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * See file CREDITS for list of people who contributed to this
6  * project.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21  * MA 02111-1307 USA
22  */
23 
24 #include <common.h>
25 
26 /*
27  * RTC test
28  *
29  * The Real Time Clock (RTC) operation is verified by this test.
30  * The following features are verified:
31  *   o) RTC Power Fault
32  *	This is verified by analyzing the rtc_get() return status.
33  *   o) Time uniformity
34  *      This is verified by reading RTC in polling within
35  *      a short period of time.
36  *   o) Passing month boundaries
37  *      This is checked by setting RTC to a second before
38  *      a month boundary and reading it after its passing the
39  *      boundary. The test is performed for both leap- and
40  *      nonleap-years.
41  */
42 
43 #include <post.h>
44 #include <rtc.h>
45 
46 #if CONFIG_POST & CONFIG_SYS_POST_RTC
47 
48 static int rtc_post_skip (ulong * diff)
49 {
50 	struct rtc_time tm1;
51 	struct rtc_time tm2;
52 	ulong start1;
53 	ulong start2;
54 
55 	rtc_get (&tm1);
56 	start1 = get_timer (0);
57 
58 	while (1) {
59 		rtc_get (&tm2);
60 		start2 = get_timer (0);
61 		if (tm1.tm_sec != tm2.tm_sec)
62 			break;
63 		if (start2 - start1 > 1500)
64 			break;
65 	}
66 
67 	if (tm1.tm_sec != tm2.tm_sec) {
68 		*diff = start2 - start1;
69 
70 		return 0;
71 	} else {
72 		return -1;
73 	}
74 }
75 
76 static void rtc_post_restore (struct rtc_time *tm, unsigned int sec)
77 {
78 	time_t t = mktime (tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_hour,
79 					   tm->tm_min, tm->tm_sec) + sec;
80 	struct rtc_time ntm;
81 
82 	to_tm (t, &ntm);
83 
84 	rtc_set (&ntm);
85 }
86 
87 int rtc_post_test (int flags)
88 {
89 	ulong diff;
90 	unsigned int i;
91 	struct rtc_time svtm;
92 	static unsigned int daysnl[] =
93 			{ 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
94 	static unsigned int daysl[] =
95 			{ 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
96 	unsigned int ynl = 1999;
97 	unsigned int yl = 2000;
98 	unsigned int skipped = 0;
99 	int reliable;
100 
101 	/* Time reliability */
102 	reliable = rtc_get (&svtm);
103 
104 	/* Time uniformity */
105 	if (rtc_post_skip (&diff) != 0) {
106 		post_log ("Timeout while waiting for a new second !\n");
107 
108 		return -1;
109 	}
110 
111 	for (i = 0; i < 5; i++) {
112 		if (rtc_post_skip (&diff) != 0) {
113 			post_log ("Timeout while waiting for a new second !\n");
114 
115 			return -1;
116 		}
117 
118 		if (diff < 950 || diff > 1050) {
119 			post_log ("Invalid second duration !\n");
120 
121 			return -1;
122 		}
123 	}
124 
125 	/* Passing month boundaries */
126 
127 	if (rtc_post_skip (&diff) != 0) {
128 		post_log ("Timeout while waiting for a new second !\n");
129 
130 		return -1;
131 	}
132 	rtc_get (&svtm);
133 
134 	for (i = 0; i < 12; i++) {
135 		time_t t = mktime (ynl, i + 1, daysnl[i], 23, 59, 59);
136 		struct rtc_time tm;
137 
138 		to_tm (t, &tm);
139 		rtc_set (&tm);
140 
141 		skipped++;
142 		if (rtc_post_skip (&diff) != 0) {
143 			rtc_post_restore (&svtm, skipped);
144 			post_log ("Timeout while waiting for a new second !\n");
145 
146 			return -1;
147 		}
148 
149 		rtc_get (&tm);
150 		if (tm.tm_mon == i + 1) {
151 			rtc_post_restore (&svtm, skipped);
152 			post_log ("Month %d boundary is not passed !\n", i + 1);
153 
154 			return -1;
155 		}
156 	}
157 
158 	for (i = 0; i < 12; i++) {
159 		time_t t = mktime (yl, i + 1, daysl[i], 23, 59, 59);
160 		struct rtc_time tm;
161 
162 		to_tm (t, &tm);
163 		rtc_set (&tm);
164 
165 		skipped++;
166 		if (rtc_post_skip (&diff) != 0) {
167 			rtc_post_restore (&svtm, skipped);
168 			post_log ("Timeout while waiting for a new second !\n");
169 
170 			return -1;
171 		}
172 
173 		rtc_get (&tm);
174 		if (tm.tm_mon == i + 1) {
175 			rtc_post_restore (&svtm, skipped);
176 			post_log ("Month %d boundary is not passed !\n", i + 1);
177 
178 			return -1;
179 		}
180 	}
181 	rtc_post_restore (&svtm, skipped);
182 
183 	/* If come here, then RTC operates correcty, check the correctness
184 	 * of the time it reports.
185 	 */
186 	if (reliable < 0) {
187 		post_log ("RTC Time is not reliable! Power fault? \n");
188 
189 		return -1;
190 	}
191 
192 	return 0;
193 }
194 
195 #endif /* CONFIG_POST & CONFIG_SYS_POST_RTC */
196