xref: /openbmc/u-boot/drivers/rtc/pl031.c (revision 8d811ca3)
1 /*
2  * (C) Copyright 2008
3  * Gururaja Hebbar gururajakr@sanyo.co.in
4  *
5  * reference linux-2.6.20.6/drivers/rtc/rtc-pl031.c
6  *
7  * See file CREDITS for list of people who contributed to this
8  * project.
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License as
12  * published by the Free Software Foundation; either version 2 of
13  * the License, or (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
23  * MA 02111-1307 USA
24  */
25 
26 #include <common.h>
27 #include <command.h>
28 #include <rtc.h>
29 
30 #if defined(CONFIG_CMD_DATE)
31 
32 #ifndef CONFIG_SYS_RTC_PL031_BASE
33 #error CONFIG_SYS_RTC_PL031_BASE is not defined!
34 #endif
35 
36 /*
37  * Register definitions
38  */
39 #define	RTC_DR		0x00	/* Data read register */
40 #define	RTC_MR		0x04	/* Match register */
41 #define	RTC_LR		0x08	/* Data load register */
42 #define	RTC_CR		0x0c	/* Control register */
43 #define	RTC_IMSC	0x10	/* Interrupt mask and set register */
44 #define	RTC_RIS		0x14	/* Raw interrupt status register */
45 #define	RTC_MIS		0x18	/* Masked interrupt status register */
46 #define	RTC_ICR		0x1c	/* Interrupt clear register */
47 
48 #define RTC_CR_START	(1 << 0)
49 
50 #define	RTC_WRITE_REG(addr, val) \
51 			(*(volatile unsigned int *)(CONFIG_SYS_RTC_PL031_BASE + (addr)) = (val))
52 #define	RTC_READ_REG(addr)	\
53 			(*(volatile unsigned int *)(CONFIG_SYS_RTC_PL031_BASE + (addr)))
54 
55 static int pl031_initted = 0;
56 
57 /* Enable RTC Start in Control register*/
58 void rtc_init(void)
59 {
60 	RTC_WRITE_REG(RTC_CR, RTC_CR_START);
61 
62 	pl031_initted = 1;
63 }
64 
65 /*
66  * Reset the RTC. We set the date back to 1970-01-01.
67  */
68 void rtc_reset(void)
69 {
70 	RTC_WRITE_REG(RTC_LR, 0x00);
71 	if(!pl031_initted)
72 		rtc_init();
73 }
74 
75 /*
76  * Set the RTC
77 */
78 int rtc_set(struct rtc_time *tmp)
79 {
80 	unsigned long tim;
81 
82 	if(!pl031_initted)
83 		rtc_init();
84 
85 	if (tmp == NULL) {
86 		puts("Error setting the date/time\n");
87 		return -1;
88 	}
89 
90 	/* Calculate number of seconds this incoming time represents */
91 	tim = mktime(tmp->tm_year, tmp->tm_mon, tmp->tm_mday,
92 	                tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
93 
94 	RTC_WRITE_REG(RTC_LR, tim);
95 
96 	return -1;
97 }
98 
99 /*
100  * Get the current time from the RTC
101  */
102 int rtc_get(struct rtc_time *tmp)
103 {
104 	ulong tim;
105 
106 	if(!pl031_initted)
107 		rtc_init();
108 
109 	if (tmp == NULL) {
110 		puts("Error getting the date/time\n");
111 		return -1;
112 	}
113 
114 	tim = RTC_READ_REG(RTC_DR);
115 
116 	to_tm (tim, tmp);
117 
118 	debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
119 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
120 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
121 
122 	return 0;
123 }
124 
125 #endif
126