1 /* 2 * (C) Copyright 2001 3 * ARIO Data Networks, Inc. dchiu@ariodata.com 4 * 5 * Based on MontaVista DS1743 code and U-Boot mc146818 code 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 the DS174x RTC 28 */ 29 30 /*#define DEBUG*/ 31 32 #include <common.h> 33 #include <command.h> 34 #include <rtc.h> 35 36 #if defined(CONFIG_RTC_DS174x) && defined(CONFIG_CMD_DATE) 37 38 static uchar rtc_read( unsigned int addr ); 39 static void rtc_write( unsigned int addr, uchar val); 40 static uchar bin2bcd (unsigned int n); 41 static unsigned bcd2bin(uchar c); 42 43 #define RTC_BASE ( CFG_NVRAM_SIZE + CFG_NVRAM_BASE_ADDR ) 44 45 #define RTC_YEAR ( RTC_BASE + 7 ) 46 #define RTC_MONTH ( RTC_BASE + 6 ) 47 #define RTC_DAY_OF_MONTH ( RTC_BASE + 5 ) 48 #define RTC_DAY_OF_WEEK ( RTC_BASE + 4 ) 49 #define RTC_HOURS ( RTC_BASE + 3 ) 50 #define RTC_MINUTES ( RTC_BASE + 2 ) 51 #define RTC_SECONDS ( RTC_BASE + 1 ) 52 #define RTC_CENTURY ( RTC_BASE + 0 ) 53 54 #define RTC_CONTROLA RTC_CENTURY 55 #define RTC_CONTROLB RTC_SECONDS 56 #define RTC_CONTROLC RTC_DAY_OF_WEEK 57 58 #define RTC_CA_WRITE 0x80 59 #define RTC_CA_READ 0x40 60 61 #define RTC_CB_OSC_DISABLE 0x80 62 63 #define RTC_CC_BATTERY_FLAG 0x80 64 #define RTC_CC_FREQ_TEST 0x40 65 66 /* ------------------------------------------------------------------------- */ 67 68 void rtc_get( struct rtc_time *tmp ) 69 { 70 uchar sec, min, hour; 71 uchar mday, wday, mon, year; 72 73 int century; 74 75 uchar reg_a; 76 77 reg_a = rtc_read( RTC_CONTROLA ); 78 /* lock clock registers for read */ 79 rtc_write( RTC_CONTROLA, ( reg_a | RTC_CA_READ )); 80 81 sec = rtc_read( RTC_SECONDS ); 82 min = rtc_read( RTC_MINUTES ); 83 hour = rtc_read( RTC_HOURS ); 84 mday = rtc_read( RTC_DAY_OF_MONTH ); 85 wday = rtc_read( RTC_DAY_OF_WEEK ); 86 mon = rtc_read( RTC_MONTH ); 87 year = rtc_read( RTC_YEAR ); 88 century = rtc_read( RTC_CENTURY ); 89 90 /* unlock clock registers after read */ 91 rtc_write( RTC_CONTROLA, ( reg_a & ~RTC_CA_READ )); 92 93 #ifdef RTC_DEBUG 94 printf( "Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x " 95 "hr: %02x min: %02x sec: %02x\n", 96 year, mon_cent, mday, wday, 97 hour, min, sec ); 98 #endif 99 tmp->tm_sec = bcd2bin( sec & 0x7F ); 100 tmp->tm_min = bcd2bin( min & 0x7F ); 101 tmp->tm_hour = bcd2bin( hour & 0x3F ); 102 tmp->tm_mday = bcd2bin( mday & 0x3F ); 103 tmp->tm_mon = bcd2bin( mon & 0x1F ); 104 tmp->tm_wday = bcd2bin( wday & 0x07 ); 105 106 /* glue year from century and year in century */ 107 tmp->tm_year = bcd2bin( year ) + 108 ( bcd2bin( century & 0x3F ) * 100 ); 109 110 tmp->tm_yday = 0; 111 tmp->tm_isdst= 0; 112 #ifdef RTC_DEBUG 113 printf( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 114 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 115 tmp->tm_hour, tmp->tm_min, tmp->tm_sec ); 116 #endif 117 } 118 119 void rtc_set( struct rtc_time *tmp ) 120 { 121 uchar reg_a; 122 #ifdef RTC_DEBUG 123 printf( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 124 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 125 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 126 #endif 127 /* lock clock registers for write */ 128 reg_a = rtc_read( RTC_CONTROLA ); 129 rtc_write( RTC_CONTROLA, ( reg_a | RTC_CA_WRITE )); 130 131 rtc_write( RTC_MONTH, bin2bcd( tmp->tm_mon )); 132 133 rtc_write( RTC_DAY_OF_WEEK, bin2bcd( tmp->tm_wday )); 134 rtc_write( RTC_DAY_OF_MONTH, bin2bcd( tmp->tm_mday )); 135 rtc_write( RTC_HOURS, bin2bcd( tmp->tm_hour )); 136 rtc_write( RTC_MINUTES, bin2bcd( tmp->tm_min )); 137 rtc_write( RTC_SECONDS, bin2bcd( tmp->tm_sec )); 138 139 /* break year up into century and year in century */ 140 rtc_write( RTC_YEAR, bin2bcd( tmp->tm_year % 100 )); 141 rtc_write( RTC_CENTURY, bin2bcd( tmp->tm_year / 100 )); 142 143 /* unlock clock registers after read */ 144 rtc_write( RTC_CONTROLA, ( reg_a & ~RTC_CA_WRITE )); 145 } 146 147 void rtc_reset (void) 148 { 149 uchar reg_a, reg_b, reg_c; 150 151 reg_a = rtc_read( RTC_CONTROLA ); 152 reg_b = rtc_read( RTC_CONTROLB ); 153 154 if ( reg_b & RTC_CB_OSC_DISABLE ) 155 { 156 printf( "real-time-clock was stopped. Now starting...\n" ); 157 reg_a |= RTC_CA_WRITE; 158 reg_b &= ~RTC_CB_OSC_DISABLE; 159 160 rtc_write( RTC_CONTROLA, reg_a ); 161 rtc_write( RTC_CONTROLB, reg_b ); 162 } 163 164 /* make sure read/write clock register bits are cleared */ 165 reg_a &= ~( RTC_CA_WRITE | RTC_CA_READ ); 166 rtc_write( RTC_CONTROLA, reg_a ); 167 168 reg_c = rtc_read( RTC_CONTROLC ); 169 if (( reg_c & RTC_CC_BATTERY_FLAG ) == 0 ) 170 printf( "RTC battery low. Clock setting may not be reliable.\n" ); 171 } 172 173 /* ------------------------------------------------------------------------- */ 174 175 static uchar rtc_read( unsigned int addr ) 176 { 177 uchar val = in8( addr ); 178 #ifdef RTC_DEBUG 179 printf( "rtc_read: %x:%x\n", addr, val ); 180 #endif 181 return( val ); 182 } 183 184 static void rtc_write( unsigned int addr, uchar val ) 185 { 186 #ifdef RTC_DEBUG 187 printf( "rtc_write: %x:%x\n", addr, val ); 188 #endif 189 out8( addr, val ); 190 } 191 192 static unsigned bcd2bin (uchar n) 193 { 194 return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F)); 195 } 196 197 static unsigned char bin2bcd (unsigned int n) 198 { 199 return (((n / 10) << 4) | (n % 10)); 200 } 201 202 #endif 203