drivers/rtc/mpc5xxx.c

   1 /*
   2  * (C) Copyright 2004
   3  * Reinhard Meyer, EMK Elektronik GmbH
   4  * r.meyer@emk-elektronik.de
   5  * www.emk-elektronik.de
   6  *
   7  * SPDX-License-Identifier:     GPL-2.0+
   8  */
   9
  10 /*****************************************************************************
  11  * Date & Time support for internal RTC of MPC52xx
  12  *****************************************************************************/
  13 /*#define       DEBUG*/
  14
  15 #include <common.h>
  16 #include <command.h>
  17 #include <rtc.h>
  18
  19 #if defined(CONFIG_CMD_DATE)
  20
  21 /*****************************************************************************
  22  * this structure should be defined in mpc5200.h ...
  23  *****************************************************************************/
  24 typedef struct rtc5200 {
  25         volatile ulong  tsr;    /* MBAR+0x800: time set register */
  26         volatile ulong  dsr;    /* MBAR+0x804: data set register */
  27         volatile ulong  nysr;   /* MBAR+0x808: new year and stopwatch register */
  28         volatile ulong  aier;   /* MBAR+0x80C: alarm and interrupt enable register */
  29         volatile ulong  ctr;    /* MBAR+0x810: current time register */
  30         volatile ulong  cdr;    /* MBAR+0x814: current data register */
  31         volatile ulong  asir;   /* MBAR+0x818: alarm and stopwatch interrupt register */
  32         volatile ulong  piber;  /* MBAR+0x81C: periodic interrupt and bus error register */
  33         volatile ulong  trdr;   /* MBAR+0x820: test register/divides register */
  34 } RTC5200;
  35
  36 #define RTC_SET         0x02000000
  37 #define RTC_PAUSE       0x01000000
  38
  39 /*****************************************************************************
  40  * get time
  41  *****************************************************************************/
  42 int rtc_get (struct rtc_time *tmp)
  43 {
  44         RTC5200 *rtc = (RTC5200 *) (CONFIG_SYS_MBAR+0x800);
  45         ulong time, date, time2;
  46
  47         /* read twice to avoid getting a funny time when the second is just changing */
  48         do {
  49                 time = rtc->ctr;
  50                 date = rtc->cdr;
  51                 time2 = rtc->ctr;
  52         } while (time != time2);
  53
  54         tmp->tm_year    = date & 0xfff;
  55         tmp->tm_mon             = (date >> 24) & 0xf;
  56         tmp->tm_mday    = (date >> 16) & 0x1f;
  57         tmp->tm_wday    = (date >> 21) & 7;
  58         /* sunday is 7 in 5200 but 0 in rtc_time */
  59         if (tmp->tm_wday == 7)
  60                 tmp->tm_wday = 0;
  61         tmp->tm_hour    = (time >> 16) & 0x1f;
  62         tmp->tm_min             = (time >> 8) & 0x3f;
  63         tmp->tm_sec             = time & 0x3f;
  64
  65         debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
  66                 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
  67                 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
  68
  69         return 0;
  70 }
  71
  72 /*****************************************************************************
  73  * set time
  74  *****************************************************************************/
  75 int rtc_set (struct rtc_time *tmp)
  76 {
  77         RTC5200 *rtc = (RTC5200 *) (CONFIG_SYS_MBAR+0x800);
  78         ulong time, date, year;
  79
  80         debug ( "Set DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
  81                 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
  82                 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
  83
  84         time = (tmp->tm_hour << 16) | (tmp->tm_min << 8) | tmp->tm_sec;
  85         date = (tmp->tm_mon << 16) | tmp->tm_mday;
  86         if (tmp->tm_wday == 0)
  87                 date |= (7 << 8);
  88         else
  89                 date |= (tmp->tm_wday << 8);
  90         year = tmp->tm_year;
  91
  92         /* mask unwanted bits that might show up when rtc_time is corrupt */
  93         time &= 0x001f3f3f;
  94         date &= 0x001f071f;
  95         year &= 0x00000fff;
  96
  97         /* pause and set the RTC */
  98         rtc->nysr = year;
  99         rtc->dsr = date | RTC_PAUSE;
 100         udelay (1000);
 101         rtc->dsr = date | RTC_PAUSE | RTC_SET;
 102         udelay (1000);
 103         rtc->dsr = date | RTC_PAUSE;
 104         udelay (1000);
 105         rtc->dsr = date;
 106         udelay (1000);
 107
 108         rtc->tsr = time | RTC_PAUSE;
 109         udelay (1000);
 110         rtc->tsr = time | RTC_PAUSE | RTC_SET;
 111         udelay (1000);
 112         rtc->tsr = time | RTC_PAUSE;
 113         udelay (1000);
 114         rtc->tsr = time;
 115         udelay (1000);
 116
 117         return 0;
 118 }
 119
 120 /*****************************************************************************
 121  * reset rtc circuit
 122  *****************************************************************************/
 123 void rtc_reset (void)
 124 {
 125         return; /* nothing to do */
 126 }
 127
 128 #endif