xref: /openbmc/u-boot/drivers/rtc/pl031.c (revision 6b44ae6b)
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  * SPDX-License-Identifier:	GPL-2.0+
8  */
9 
10 #include <common.h>
11 #include <command.h>
12 #include <rtc.h>
13 
14 #if defined(CONFIG_CMD_DATE)
15 
16 #ifndef CONFIG_SYS_RTC_PL031_BASE
17 #error CONFIG_SYS_RTC_PL031_BASE is not defined!
18 #endif
19 
20 /*
21  * Register definitions
22  */
23 #define	RTC_DR		0x00	/* Data read register */
24 #define	RTC_MR		0x04	/* Match register */
25 #define	RTC_LR		0x08	/* Data load register */
26 #define	RTC_CR		0x0c	/* Control register */
27 #define	RTC_IMSC	0x10	/* Interrupt mask and set register */
28 #define	RTC_RIS		0x14	/* Raw interrupt status register */
29 #define	RTC_MIS		0x18	/* Masked interrupt status register */
30 #define	RTC_ICR		0x1c	/* Interrupt clear register */
31 
32 #define RTC_CR_START	(1 << 0)
33 
34 #define	RTC_WRITE_REG(addr, val) \
35 			(*(volatile unsigned int *)(CONFIG_SYS_RTC_PL031_BASE + (addr)) = (val))
36 #define	RTC_READ_REG(addr)	\
37 			(*(volatile unsigned int *)(CONFIG_SYS_RTC_PL031_BASE + (addr)))
38 
39 static int pl031_initted = 0;
40 
41 /* Enable RTC Start in Control register*/
42 void rtc_init(void)
43 {
44 	RTC_WRITE_REG(RTC_CR, RTC_CR_START);
45 
46 	pl031_initted = 1;
47 }
48 
49 /*
50  * Reset the RTC. We set the date back to 1970-01-01.
51  */
52 void rtc_reset(void)
53 {
54 	RTC_WRITE_REG(RTC_LR, 0x00);
55 	if(!pl031_initted)
56 		rtc_init();
57 }
58 
59 /*
60  * Set the RTC
61 */
62 int rtc_set(struct rtc_time *tmp)
63 {
64 	unsigned long tim;
65 
66 	if(!pl031_initted)
67 		rtc_init();
68 
69 	if (tmp == NULL) {
70 		puts("Error setting the date/time\n");
71 		return -1;
72 	}
73 
74 	/* Calculate number of seconds this incoming time represents */
75 	tim = rtc_mktime(tmp);
76 
77 	RTC_WRITE_REG(RTC_LR, tim);
78 
79 	return -1;
80 }
81 
82 /*
83  * Get the current time from the RTC
84  */
85 int rtc_get(struct rtc_time *tmp)
86 {
87 	ulong tim;
88 
89 	if(!pl031_initted)
90 		rtc_init();
91 
92 	if (tmp == NULL) {
93 		puts("Error getting the date/time\n");
94 		return -1;
95 	}
96 
97 	tim = RTC_READ_REG(RTC_DR);
98 
99 	rtc_to_tm(tim, tmp);
100 
101 	debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
102 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
103 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
104 
105 	return 0;
106 }
107 
108 #endif
109