1 /* 2 * (C) Copyright 2002 3 * ARIO Data Networks, Inc. dchiu@ariodata.com 4 * 5 * modified for DS164x: 6 * The LEOX team <team@leox.org>, http://www.leox.org 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 DS164x RTC 31 */ 32 33 /* #define RTC_DEBUG */ 34 35 #include <common.h> 36 #include <command.h> 37 #include <rtc.h> 38 39 40 #if defined(CONFIG_CMD_DATE) 41 42 static uchar rtc_read(unsigned int addr ); 43 static void rtc_write(unsigned int addr, uchar val); 44 static uchar bin2bcd(unsigned int n); 45 static unsigned bcd2bin(uchar c); 46 47 #define RTC_EPOCH 2000 /* century */ 48 49 /* 50 * DS164x registers layout 51 */ 52 #define RTC_BASE ( CONFIG_SYS_NVRAM_BASE_ADDR + CONFIG_SYS_NVRAM_SIZE ) 53 54 #define RTC_YEAR ( RTC_BASE + 0x07 ) 55 #define RTC_MONTH ( RTC_BASE + 0x06 ) 56 #define RTC_DAY_OF_MONTH ( RTC_BASE + 0x05 ) 57 #define RTC_DAY_OF_WEEK ( RTC_BASE + 0x04 ) 58 #define RTC_HOURS ( RTC_BASE + 0x03 ) 59 #define RTC_MINUTES ( RTC_BASE + 0x02 ) 60 #define RTC_SECONDS ( RTC_BASE + 0x01 ) 61 #define RTC_CONTROL ( RTC_BASE + 0x00 ) 62 63 #define RTC_CONTROLA RTC_CONTROL /* W=bit6, R=bit5 */ 64 #define RTC_CA_WRITE 0x80 65 #define RTC_CA_READ 0x40 66 #define RTC_CONTROLB RTC_SECONDS /* OSC=bit7 */ 67 #define RTC_CB_OSC_DISABLE 0x80 68 #define RTC_CONTROLC RTC_DAY_OF_WEEK /* FT=bit6 */ 69 #define RTC_CC_FREQ_TEST 0x40 70 71 /* ------------------------------------------------------------------------- */ 72 73 int rtc_get( struct rtc_time *tmp ) 74 { 75 uchar sec, min, hour; 76 uchar mday, wday, mon, year; 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 92 /* unlock clock registers after read */ 93 rtc_write( RTC_CONTROLA, ( reg_a & ~RTC_CA_READ )); 94 95 #ifdef RTC_DEBUG 96 printf( "Get RTC year: %02x mon: %02x mday: %02x wday: %02x " 97 "hr: %02x min: %02x sec: %02x\n", 98 year, mon, mday, wday, 99 hour, min, sec ); 100 #endif 101 tmp->tm_sec = bcd2bin( sec & 0x7F ); 102 tmp->tm_min = bcd2bin( min & 0x7F ); 103 tmp->tm_hour = bcd2bin( hour & 0x3F ); 104 tmp->tm_mday = bcd2bin( mday & 0x3F ); 105 tmp->tm_mon = bcd2bin( mon & 0x1F ); 106 tmp->tm_wday = bcd2bin( wday & 0x07 ); 107 108 /* glue year in century (2000) */ 109 tmp->tm_year = bcd2bin( year ) + RTC_EPOCH; 110 111 tmp->tm_yday = 0; 112 tmp->tm_isdst= 0; 113 #ifdef RTC_DEBUG 114 printf( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 115 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 116 tmp->tm_hour, tmp->tm_min, tmp->tm_sec ); 117 #endif 118 119 return 0; 120 } 121 122 int rtc_set( struct rtc_time *tmp ) 123 { 124 uchar reg_a; 125 126 #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 in century */ 144 rtc_write( RTC_YEAR, bin2bcd( tmp->tm_year % 100 )); 145 146 /* unlock clock registers after read */ 147 rtc_write( RTC_CONTROLA, ( reg_a & ~RTC_CA_WRITE )); 148 149 return 0; 150 } 151 152 void rtc_reset (void) 153 { 154 uchar reg_a, reg_b; 155 156 reg_a = rtc_read( RTC_CONTROLA ); 157 reg_b = rtc_read( RTC_CONTROLB ); 158 159 if ( reg_b & RTC_CB_OSC_DISABLE ) 160 { 161 printf( "real-time-clock was stopped. Now starting...\n" ); 162 reg_a |= RTC_CA_WRITE; 163 reg_b &= ~RTC_CB_OSC_DISABLE; 164 165 rtc_write( RTC_CONTROLA, reg_a ); 166 rtc_write( RTC_CONTROLB, reg_b ); 167 } 168 169 /* make sure read/write clock register bits are cleared */ 170 reg_a &= ~( RTC_CA_WRITE | RTC_CA_READ ); 171 rtc_write( RTC_CONTROLA, reg_a ); 172 } 173 174 /* ------------------------------------------------------------------------- */ 175 176 static uchar rtc_read( unsigned int addr ) 177 { 178 uchar val = *(volatile unsigned char*)(addr); 179 180 #ifdef RTC_DEBUG 181 printf( "rtc_read: %x:%x\n", addr, val ); 182 #endif 183 return( val ); 184 } 185 186 static void rtc_write( unsigned int addr, uchar val ) 187 { 188 #ifdef RTC_DEBUG 189 printf( "rtc_write: %x:%x\n", addr, val ); 190 #endif 191 *(volatile unsigned char*)(addr) = val; 192 } 193 194 static unsigned bcd2bin (uchar n) 195 { 196 return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F)); 197 } 198 199 static unsigned char bin2bcd (unsigned int n) 200 { 201 return (((n / 10) << 4) | (n % 10)); 202 } 203 204 #endif 205