xref: /openbmc/u-boot/drivers/rtc/pl031.c (revision 78a88f79)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2008
4  * Gururaja Hebbar gururajakr@sanyo.co.in
5  *
6  * reference linux-2.6.20.6/drivers/rtc/rtc-pl031.c
7  */
8 
9 #include <common.h>
10 #include <command.h>
11 #include <rtc.h>
12 
13 #if defined(CONFIG_CMD_DATE)
14 
15 #ifndef CONFIG_SYS_RTC_PL031_BASE
16 #error CONFIG_SYS_RTC_PL031_BASE is not defined!
17 #endif
18 
19 /*
20  * Register definitions
21  */
22 #define	RTC_DR		0x00	/* Data read register */
23 #define	RTC_MR		0x04	/* Match register */
24 #define	RTC_LR		0x08	/* Data load register */
25 #define	RTC_CR		0x0c	/* Control register */
26 #define	RTC_IMSC	0x10	/* Interrupt mask and set register */
27 #define	RTC_RIS		0x14	/* Raw interrupt status register */
28 #define	RTC_MIS		0x18	/* Masked interrupt status register */
29 #define	RTC_ICR		0x1c	/* Interrupt clear register */
30 
31 #define RTC_CR_START	(1 << 0)
32 
33 #define	RTC_WRITE_REG(addr, val) \
34 			(*(volatile unsigned int *)(CONFIG_SYS_RTC_PL031_BASE + (addr)) = (val))
35 #define	RTC_READ_REG(addr)	\
36 			(*(volatile unsigned int *)(CONFIG_SYS_RTC_PL031_BASE + (addr)))
37 
38 static int pl031_initted = 0;
39 
40 /* Enable RTC Start in Control register*/
41 void rtc_init(void)
42 {
43 	RTC_WRITE_REG(RTC_CR, RTC_CR_START);
44 
45 	pl031_initted = 1;
46 }
47 
48 /*
49  * Reset the RTC. We set the date back to 1970-01-01.
50  */
51 void rtc_reset(void)
52 {
53 	RTC_WRITE_REG(RTC_LR, 0x00);
54 	if(!pl031_initted)
55 		rtc_init();
56 }
57 
58 /*
59  * Set the RTC
60 */
61 int rtc_set(struct rtc_time *tmp)
62 {
63 	unsigned long tim;
64 
65 	if(!pl031_initted)
66 		rtc_init();
67 
68 	if (tmp == NULL) {
69 		puts("Error setting the date/time\n");
70 		return -1;
71 	}
72 
73 	/* Calculate number of seconds this incoming time represents */
74 	tim = rtc_mktime(tmp);
75 
76 	RTC_WRITE_REG(RTC_LR, tim);
77 
78 	return -1;
79 }
80 
81 /*
82  * Get the current time from the RTC
83  */
84 int rtc_get(struct rtc_time *tmp)
85 {
86 	ulong tim;
87 
88 	if(!pl031_initted)
89 		rtc_init();
90 
91 	if (tmp == NULL) {
92 		puts("Error getting the date/time\n");
93 		return -1;
94 	}
95 
96 	tim = RTC_READ_REG(RTC_DR);
97 
98 	rtc_to_tm(tim, tmp);
99 
100 	debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
101 		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
102 		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
103 
104 	return 0;
105 }
106 
107 #endif
108