drivers/rtc/mc146818.c

   1 /*
   2  * (C) Copyright 2001
   3  * Denis Peter MPL AG Switzerland. d.peter@mpl.ch
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 /*
  25  * Date & Time support for the MC146818 (PIXX4) RTC
  26  */
  27
  28 /*#define       DEBUG*/
  29
  30 #include <common.h>
  31 #include <command.h>
  32 #include <rtc.h>
  33
  34 #if defined(CONFIG_RTC_MC146818) && defined(CONFIG_CMD_DATE)
  35
  36 static uchar rtc_read  (uchar reg);
  37 static void  rtc_write (uchar reg, uchar val);
  38 static uchar bin2bcd   (unsigned int n);
  39 static unsigned bcd2bin(uchar c);
  40
  41 #define RTC_PORT_MC146818               CFG_ISA_IO_BASE_ADDRESS +  0x70
  42 #define RTC_SECONDS             0x00
  43 #define RTC_SECONDS_ALARM       0x01
  44 #define RTC_MINUTES                             0x02
  45 #define RTC_MINUTES_ALARM       0x03
  46 #define RTC_HOURS                                       0x04
  47 #define RTC_HOURS_ALARM                 0x05
  48 #define RTC_DAY_OF_WEEK                 0x06
  49 #define RTC_DATE_OF_MONTH       0x07
  50 #define RTC_MONTH                                       0x08
  51 #define RTC_YEAR                                                0x09
  52 #define RTC_CONFIG_A                            0x0A
  53 #define RTC_CONFIG_B                            0x0B
  54 #define RTC_CONFIG_C                            0x0C
  55 #define RTC_CONFIG_D                            0x0D
  56
  57
  58 /* ------------------------------------------------------------------------- */
  59
  60 int rtc_get (struct rtc_time *tmp)
  61 {
  62         uchar sec, min, hour, mday, wday, mon, year;
  63   /* here check if rtc can be accessed */
  64         while((rtc_read(RTC_CONFIG_A)&0x80)==0x80);
  65         sec             = rtc_read (RTC_SECONDS);
  66         min             = rtc_read (RTC_MINUTES);
  67         hour    = rtc_read (RTC_HOURS);
  68         mday    = rtc_read (RTC_DATE_OF_MONTH);
  69         wday    = rtc_read (RTC_DAY_OF_WEEK);
  70         mon             = rtc_read (RTC_MONTH);
  71         year    = rtc_read (RTC_YEAR);
  72 #ifdef CONFIG_AMIGAONEG3SE
  73         wday -= 1; /* VIA 686 stores Sunday = 1, Monday = 2, ... */
  74 #endif
  75 #ifdef RTC_DEBUG
  76         printf ( "Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x "
  77                 "hr: %02x min: %02x sec: %02x\n",
  78                 year, mon, mday, wday,
  79                 hour, min, sec );
  80         printf ( "Alarms: month: %02x hour: %02x min: %02x sec: %02x\n",
  81                 rtc_read (RTC_CONFIG_D) & 0x3F,
  82                 rtc_read (RTC_HOURS_ALARM),
  83                 rtc_read (RTC_MINUTES_ALARM),
  84                 rtc_read (RTC_SECONDS_ALARM) );
  85 #endif
  86         tmp->tm_sec  = bcd2bin (sec  & 0x7F);
  87         tmp->tm_min  = bcd2bin (min  & 0x7F);
  88         tmp->tm_hour = bcd2bin (hour & 0x3F);
  89         tmp->tm_mday = bcd2bin (mday & 0x3F);
  90         tmp->tm_mon  = bcd2bin (mon & 0x1F);
  91         tmp->tm_year = bcd2bin (year);
  92         tmp->tm_wday = bcd2bin (wday & 0x07);
  93         if(tmp->tm_year<70)
  94                 tmp->tm_year+=2000;
  95         else
  96                 tmp->tm_year+=1900;
  97         tmp->tm_yday = 0;
  98         tmp->tm_isdst= 0;
  99 #ifdef RTC_DEBUG
 100         printf ( "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 #endif
 104
 105         return 0;
 106 }
 107
 108 void rtc_set (struct rtc_time *tmp)
 109 {
 110 #ifdef RTC_DEBUG
 111         printf ( "Set DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
 112                 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
 113                 tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
 114 #endif
 115         rtc_write(RTC_CONFIG_B,0x82); /* disables the RTC to update the regs */
 116
 117         rtc_write (RTC_YEAR, bin2bcd(tmp->tm_year % 100));
 118         rtc_write (RTC_MONTH, bin2bcd(tmp->tm_mon));
 119 #ifdef CONFIG_AMIGAONEG3SE
 120         rtc_write (RTC_DAY_OF_WEEK, bin2bcd(tmp->tm_wday)+1);
 121 #else
 122         rtc_write (RTC_DAY_OF_WEEK, bin2bcd(tmp->tm_wday));
 123 #endif
 124         rtc_write (RTC_DATE_OF_MONTH, bin2bcd(tmp->tm_mday));
 125         rtc_write (RTC_HOURS, bin2bcd(tmp->tm_hour));
 126         rtc_write (RTC_MINUTES, bin2bcd(tmp->tm_min ));
 127         rtc_write (RTC_SECONDS, bin2bcd(tmp->tm_sec ));
 128         rtc_write(RTC_CONFIG_B,0x02); /* enables the RTC to update the regs */
 129
 130 }
 131
 132 void rtc_reset (void)
 133 {
 134         rtc_write(RTC_CONFIG_B,0x82); /* disables the RTC to update the regs */
 135         rtc_write(RTC_CONFIG_A,0x20); /* Normal OP */
 136         rtc_write(RTC_CONFIG_B,0x00);
 137         rtc_write(RTC_CONFIG_B,0x00);
 138         rtc_write(RTC_CONFIG_B,0x02); /* enables the RTC to update the regs */
 139 }
 140
 141 /* ------------------------------------------------------------------------- */
 142
 143 #ifdef CFG_RTC_REG_BASE_ADDR
 144 /*
 145  * use direct memory access
 146  */
 147 static uchar rtc_read (uchar reg)
 148 {
 149         return(in8(CFG_RTC_REG_BASE_ADDR+reg));
 150 }
 151
 152 static void rtc_write (uchar reg, uchar val)
 153 {
 154         out8(CFG_RTC_REG_BASE_ADDR+reg, val);
 155 }
 156 #else
 157 static uchar rtc_read (uchar reg)
 158 {
 159         out8(RTC_PORT_MC146818,reg);
 160         return(in8(RTC_PORT_MC146818+1));
 161 }
 162
 163 static void rtc_write (uchar reg, uchar val)
 164 {
 165         out8(RTC_PORT_MC146818,reg);
 166         out8(RTC_PORT_MC146818+1,val);
 167 }
 168 #endif
 169
 170 static unsigned bcd2bin (uchar n)
 171 {
 172         return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F));
 173 }
 174
 175 static unsigned char bin2bcd (unsigned int n)
 176 {
 177         return (((n / 10) << 4) | (n % 10));
 178 }
 179
 180 #endif