1 /* 2 * (C) Copyright 2002 3 * ARIO Data Networks, Inc. dchiu@ariodata.com 4 * 5 * modified for DS1556: 6 * Frank Panno <fpanno@delphintech.com>, Delphin Technology AG 7 * 8 * Based on MontaVista DS1743 code and U-Boot mc146818 code 9 * 10 * See file CREDITS for list of people who contributed to this 11 * project. 12 * 13 * This program is free software; you can redistribute it and/or 14 * modify it under the terms of the GNU General Public License as 15 * published by the Free Software Foundation; either version 2 of 16 * the License, or (at your option) any later version. 17 * 18 * This program is distributed in the hope that it will be useful, 19 * but WITHOUT ANY WARRANTY; without even the implied warranty of 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 21 * GNU General Public License for more details. 22 * 23 * You should have received a copy of the GNU General Public License 24 * along with this program; if not, write to the Free Software 25 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 26 * MA 02111-1307 USA 27 */ 28 29 /* 30 * Date & Time support for the DS1556 RTC 31 */ 32 33 /*#define RTC_DEBUG */ 34 35 #include <common.h> 36 #include <command.h> 37 #include <rtc.h> 38 39 #if defined(CONFIG_CMD_DATE) 40 41 static uchar rtc_read( unsigned int addr ); 42 static void rtc_write( unsigned int addr, uchar val); 43 static uchar bin2bcd (unsigned int n); 44 static unsigned bcd2bin(uchar c); 45 46 #define RTC_BASE ( CFG_NVRAM_SIZE + CFG_NVRAM_BASE_ADDR ) 47 48 #define RTC_YEAR ( RTC_BASE + 0xf ) 49 #define RTC_MONTH ( RTC_BASE + 0xe ) 50 #define RTC_DAY_OF_MONTH ( RTC_BASE + 0xd ) 51 #define RTC_DAY_OF_WEEK ( RTC_BASE + 0xc ) 52 #define RTC_HOURS ( RTC_BASE + 0xb ) 53 #define RTC_MINUTES ( RTC_BASE + 0xa ) 54 #define RTC_SECONDS ( RTC_BASE + 0x9 ) 55 #define RTC_CENTURY ( RTC_BASE + 0x8 ) 56 57 #define RTC_CONTROLA RTC_CENTURY 58 #define RTC_CONTROLB RTC_SECONDS 59 #define RTC_CONTROLC RTC_BASE 60 61 #define RTC_CA_WRITE 0x80 62 #define RTC_CA_READ 0x40 63 64 #define RTC_CB_OSC_DISABLE 0x80 65 66 #define RTC_CC_BATTERY_FLAG 0x10 67 #define RTC_CC_FREQ_TEST 0x40 68 69 /* ------------------------------------------------------------------------- */ 70 71 int rtc_get( struct rtc_time *tmp ) 72 { 73 uchar sec, min, hour; 74 uchar mday, wday, mon, year; 75 76 int century; 77 78 uchar reg_a; 79 80 reg_a = rtc_read( RTC_CONTROLA ); 81 /* lock clock registers for read */ 82 rtc_write( RTC_CONTROLA, ( reg_a | RTC_CA_READ )); 83 84 sec = rtc_read( RTC_SECONDS ); 85 min = rtc_read( RTC_MINUTES ); 86 hour = rtc_read( RTC_HOURS ); 87 mday = rtc_read( RTC_DAY_OF_MONTH ); 88 wday = rtc_read( RTC_DAY_OF_WEEK ); 89 mon = rtc_read( RTC_MONTH ); 90 year = rtc_read( RTC_YEAR ); 91 century = rtc_read( RTC_CENTURY ); 92 93 /* unlock clock registers after read */ 94 rtc_write( RTC_CONTROLA, ( reg_a & ~RTC_CA_READ )); 95 96 #ifdef RTC_DEBUG 97 printf( "Get RTC year: %02x mon/cent: %02x mon: %02x mday: %02x wday: %02x " 98 "hr: %02x min: %02x sec: %02x\n", 99 year, century, mon, mday, wday, 100 hour, min, sec ); 101 #endif 102 tmp->tm_sec = bcd2bin( sec & 0x7F ); 103 tmp->tm_min = bcd2bin( min & 0x7F ); 104 tmp->tm_hour = bcd2bin( hour & 0x3F ); 105 tmp->tm_mday = bcd2bin( mday & 0x3F ); 106 tmp->tm_mon = bcd2bin( mon & 0x1F ); 107 tmp->tm_wday = bcd2bin( wday & 0x07 ); 108 109 /* glue year from century and year in century */ 110 tmp->tm_year = bcd2bin( year ) + 111 ( bcd2bin( century & 0x3F ) * 100 ); 112 113 tmp->tm_yday = 0; 114 tmp->tm_isdst= 0; 115 #ifdef RTC_DEBUG 116 printf( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 117 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 118 tmp->tm_hour, tmp->tm_min, tmp->tm_sec ); 119 #endif 120 return 0; 121 } 122 123 int rtc_set( struct rtc_time *tmp ) 124 { 125 uchar reg_a; 126 #ifdef RTC_DEBUG 127 printf( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 128 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 129 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 130 #endif 131 /* lock clock registers for write */ 132 reg_a = rtc_read( RTC_CONTROLA ); 133 rtc_write( RTC_CONTROLA, ( reg_a | RTC_CA_WRITE )); 134 135 rtc_write( RTC_MONTH, bin2bcd( tmp->tm_mon )); 136 137 rtc_write( RTC_DAY_OF_WEEK, bin2bcd( tmp->tm_wday )); 138 rtc_write( RTC_DAY_OF_MONTH, bin2bcd( tmp->tm_mday )); 139 rtc_write( RTC_HOURS, bin2bcd( tmp->tm_hour )); 140 rtc_write( RTC_MINUTES, bin2bcd( tmp->tm_min )); 141 rtc_write( RTC_SECONDS, bin2bcd( tmp->tm_sec )); 142 143 /* break year up into century and year in century */ 144 rtc_write( RTC_YEAR, bin2bcd( tmp->tm_year % 100 )); 145 rtc_write( RTC_CENTURY, bin2bcd( tmp->tm_year / 100 )); 146 147 /* unlock clock registers after read */ 148 rtc_write( RTC_CONTROLA, ( reg_a & ~RTC_CA_WRITE )); 149 150 return 0; 151 } 152 153 void rtc_reset (void) 154 { 155 uchar reg_a, reg_b, reg_c; 156 157 reg_a = rtc_read( RTC_CONTROLA ); 158 reg_b = rtc_read( RTC_CONTROLB ); 159 160 if ( reg_b & RTC_CB_OSC_DISABLE ) 161 { 162 printf( "real-time-clock was stopped. Now starting...\n" ); 163 reg_a |= RTC_CA_WRITE; 164 reg_b &= ~RTC_CB_OSC_DISABLE; 165 166 rtc_write( RTC_CONTROLA, reg_a ); 167 rtc_write( RTC_CONTROLB, reg_b ); 168 } 169 170 /* make sure read/write clock register bits are cleared */ 171 reg_a &= ~( RTC_CA_WRITE | RTC_CA_READ ); 172 rtc_write( RTC_CONTROLA, reg_a ); 173 174 reg_c = rtc_read( RTC_CONTROLC ); 175 if (( reg_c & RTC_CC_BATTERY_FLAG ) == 0 ) 176 printf( "RTC battery low. Clock setting may not be reliable.\n" ); 177 } 178 179 /* ------------------------------------------------------------------------- */ 180 181 static uchar rtc_read( unsigned int addr ) 182 { 183 uchar val = *(volatile unsigned char*)(addr); 184 #ifdef RTC_DEBUG 185 printf( "rtc_read: %x:%x\n", addr, val ); 186 #endif 187 return( val ); 188 } 189 190 static void rtc_write( unsigned int addr, uchar val ) 191 { 192 #ifdef RTC_DEBUG 193 printf( "rtc_write: %x:%x\n", addr, val ); 194 #endif 195 *(volatile unsigned char*)(addr) = val; 196 } 197 198 static unsigned bcd2bin (uchar n) 199 { 200 return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F)); 201 } 202 203 static unsigned char bin2bcd (unsigned int n) 204 { 205 return (((n / 10) << 4) | (n % 10)); 206 } 207 208 #endif 209