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  * 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 /*****************************************************************************
  27  * Date & Time support for internal RTC of MPC52xx
  28  *****************************************************************************/
  29 /*#define       DEBUG*/
  30
  31 #include <common.h>
  32 #include <command.h>
  33 #include <rtc.h>
  34
  35 #if defined(CONFIG_RTC_MPC5200) && defined(CONFIG_CMD_DATE)
  36
  37 /*****************************************************************************
  38  * this structure should be defined in mpc5200.h ...
  39  *****************************************************************************/
  40 typedef struct rtc5200 {
  41         volatile ulong  tsr;    /* MBAR+0x800: time set register */
  42         volatile ulong  dsr;    /* MBAR+0x804: data set register */
  43         volatile ulong  nysr;   /* MBAR+0x808: new year and stopwatch register */
  44         volatile ulong  aier;   /* MBAR+0x80C: alarm and interrupt enable register */
  45         volatile ulong  ctr;    /* MBAR+0x810: current time register */
  46         volatile ulong  cdr;    /* MBAR+0x814: current data register */
  47         volatile ulong  asir;   /* MBAR+0x818: alarm and stopwatch interupt register */
  48         volatile ulong  piber;  /* MBAR+0x81C: periodic interrupt and bus error register */
  49         volatile ulong  trdr;   /* MBAR+0x820: test register/divides register */
  50 } RTC5200;
  51
  52 #define RTC_SET         0x02000000
  53 #define RTC_PAUSE       0x01000000
  54
  55 /*****************************************************************************
  56  * get time
  57  *****************************************************************************/
  58 int rtc_get (struct rtc_time *tmp)
  59 {
  60         RTC5200 *rtc = (RTC5200 *) (CFG_MBAR+0x800);
  61         ulong time, date, time2;
  62
  63         /* read twice to avoid getting a funny time when the second is just changing */
  64         do {
  65                 time = rtc->ctr;
  66                 date = rtc->cdr;
  67                 time2 = rtc->ctr;
  68         } while (time != time2);
  69
  70         tmp->tm_year    = date & 0xfff;
  71         tmp->tm_mon             = (date >> 24) & 0xf;
  72         tmp->tm_mday    = (date >> 16) & 0x1f;
  73         tmp->tm_wday    = (date >> 21) & 7;
  74         /* sunday is 7 in 5200 but 0 in rtc_time */
  75         if (tmp->tm_wday == 7)
  76                 tmp->tm_wday = 0;
  77         tmp->tm_hour    = (time >> 16) & 0x1f;
  78         tmp->tm_min             = (time >> 8) & 0x3f;
  79         tmp->tm_sec             = time & 0x3f;
  80
  81         debug ( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
  82                 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
  83                 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
  84
  85         return 0;
  86 }
  87
  88 /*****************************************************************************
  89  * set time
  90  *****************************************************************************/
  91 void rtc_set (struct rtc_time *tmp)
  92 {
  93         RTC5200 *rtc = (RTC5200 *) (CFG_MBAR+0x800);
  94         ulong time, date, year;
  95
  96         debug ( "Set DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
  97                 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
  98                 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
  99
 100         time = (tmp->tm_hour << 16) | (tmp->tm_min << 8) | tmp->tm_sec;
 101         date = (tmp->tm_mon << 16) | tmp->tm_mday;
 102         if (tmp->tm_wday == 0)
 103                 date |= (7 << 8);
 104         else
 105                 date |= (tmp->tm_wday << 8);
 106         year = tmp->tm_year;
 107
 108         /* mask unwanted bits that might show up when rtc_time is corrupt */
 109         time &= 0x001f3f3f;
 110         date &= 0x001f071f;
 111         year &= 0x00000fff;
 112
 113         /* pause and set the RTC */
 114         rtc->nysr = year;
 115         rtc->dsr = date | RTC_PAUSE;
 116         udelay (1000);
 117         rtc->dsr = date | RTC_PAUSE | RTC_SET;
 118         udelay (1000);
 119         rtc->dsr = date | RTC_PAUSE;
 120         udelay (1000);
 121         rtc->dsr = date;
 122         udelay (1000);
 123
 124         rtc->tsr = time | RTC_PAUSE;
 125         udelay (1000);
 126         rtc->tsr = time | RTC_PAUSE | RTC_SET;
 127         udelay (1000);
 128         rtc->tsr = time | RTC_PAUSE;
 129         udelay (1000);
 130         rtc->tsr = time;
 131         udelay (1000);
 132 }
 133
 134 /*****************************************************************************
 135  * reset rtc circuit
 136  *****************************************************************************/
 137 void rtc_reset (void)
 138 {
 139         return; /* nothing to do */
 140 }
 141
 142 #endif