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  * 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