drivers/rtc/pl031.c

   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 = mktime(tmp->tm_year, tmp->tm_mon, tmp->tm_mday,
  76                         tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
  77
  78         RTC_WRITE_REG(RTC_LR, tim);
  79
  80         return -1;
  81 }
  82
  83 /*
  84  * Get the current time from the RTC
  85  */
  86 int rtc_get(struct rtc_time *tmp)
  87 {
  88         ulong tim;
  89
  90         if(!pl031_initted)
  91                 rtc_init();
  92
  93         if (tmp == NULL) {
  94                 puts("Error getting the date/time\n");
  95                 return -1;
  96         }
  97
  98         tim = RTC_READ_REG(RTC_DR);
  99
 100         to_tm (tim, tmp);
 101
 102         debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 103                 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 104                 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
 105
 106         return 0;
 107 }
 108
 109 #endif