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 * SPDX-License-Identifier: GPL-2.0+ 11 */ 12 13 /* 14 * Date & Time support for the DS164x RTC 15 */ 16 17 /* #define RTC_DEBUG */ 18 19 #include <common.h> 20 #include <command.h> 21 #include <rtc.h> 22 23 24 #if defined(CONFIG_CMD_DATE) 25 26 static uchar rtc_read(unsigned int addr ); 27 static void rtc_write(unsigned int addr, uchar val); 28 29 #define RTC_EPOCH 2000 /* century */ 30 31 /* 32 * DS164x registers layout 33 */ 34 #define RTC_BASE ( CONFIG_SYS_NVRAM_BASE_ADDR + CONFIG_SYS_NVRAM_SIZE ) 35 36 #define RTC_YEAR ( RTC_BASE + 0x07 ) 37 #define RTC_MONTH ( RTC_BASE + 0x06 ) 38 #define RTC_DAY_OF_MONTH ( RTC_BASE + 0x05 ) 39 #define RTC_DAY_OF_WEEK ( RTC_BASE + 0x04 ) 40 #define RTC_HOURS ( RTC_BASE + 0x03 ) 41 #define RTC_MINUTES ( RTC_BASE + 0x02 ) 42 #define RTC_SECONDS ( RTC_BASE + 0x01 ) 43 #define RTC_CONTROL ( RTC_BASE + 0x00 ) 44 45 #define RTC_CONTROLA RTC_CONTROL /* W=bit6, R=bit5 */ 46 #define RTC_CA_WRITE 0x80 47 #define RTC_CA_READ 0x40 48 #define RTC_CONTROLB RTC_SECONDS /* OSC=bit7 */ 49 #define RTC_CB_OSC_DISABLE 0x80 50 #define RTC_CONTROLC RTC_DAY_OF_WEEK /* FT=bit6 */ 51 #define RTC_CC_FREQ_TEST 0x40 52 53 /* ------------------------------------------------------------------------- */ 54 55 int rtc_get( struct rtc_time *tmp ) 56 { 57 uchar sec, min, hour; 58 uchar mday, wday, mon, year; 59 60 uchar reg_a; 61 62 reg_a = rtc_read( RTC_CONTROLA ); 63 /* lock clock registers for read */ 64 rtc_write( RTC_CONTROLA, ( reg_a | RTC_CA_READ )); 65 66 sec = rtc_read( RTC_SECONDS ); 67 min = rtc_read( RTC_MINUTES ); 68 hour = rtc_read( RTC_HOURS ); 69 mday = rtc_read( RTC_DAY_OF_MONTH ); 70 wday = rtc_read( RTC_DAY_OF_WEEK ); 71 mon = rtc_read( RTC_MONTH ); 72 year = rtc_read( RTC_YEAR ); 73 74 /* unlock clock registers after read */ 75 rtc_write( RTC_CONTROLA, ( reg_a & ~RTC_CA_READ )); 76 77 #ifdef RTC_DEBUG 78 printf( "Get RTC year: %02x mon: %02x mday: %02x wday: %02x " 79 "hr: %02x min: %02x sec: %02x\n", 80 year, mon, mday, wday, 81 hour, min, sec ); 82 #endif 83 tmp->tm_sec = bcd2bin( sec & 0x7F ); 84 tmp->tm_min = bcd2bin( min & 0x7F ); 85 tmp->tm_hour = bcd2bin( hour & 0x3F ); 86 tmp->tm_mday = bcd2bin( mday & 0x3F ); 87 tmp->tm_mon = bcd2bin( mon & 0x1F ); 88 tmp->tm_wday = bcd2bin( wday & 0x07 ); 89 90 /* glue year in century (2000) */ 91 tmp->tm_year = bcd2bin( year ) + RTC_EPOCH; 92 93 tmp->tm_yday = 0; 94 tmp->tm_isdst= 0; 95 #ifdef RTC_DEBUG 96 printf( "Get 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 #endif 100 101 return 0; 102 } 103 104 int rtc_set( struct rtc_time *tmp ) 105 { 106 uchar reg_a; 107 108 #ifdef RTC_DEBUG 109 printf( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 110 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 111 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 112 #endif 113 /* lock clock registers for write */ 114 reg_a = rtc_read( RTC_CONTROLA ); 115 rtc_write( RTC_CONTROLA, ( reg_a | RTC_CA_WRITE )); 116 117 rtc_write( RTC_MONTH, bin2bcd( tmp->tm_mon )); 118 119 rtc_write( RTC_DAY_OF_WEEK, bin2bcd( tmp->tm_wday )); 120 rtc_write( RTC_DAY_OF_MONTH, bin2bcd( tmp->tm_mday )); 121 rtc_write( RTC_HOURS, bin2bcd( tmp->tm_hour )); 122 rtc_write( RTC_MINUTES, bin2bcd( tmp->tm_min )); 123 rtc_write( RTC_SECONDS, bin2bcd( tmp->tm_sec )); 124 125 /* break year in century */ 126 rtc_write( RTC_YEAR, bin2bcd( tmp->tm_year % 100 )); 127 128 /* unlock clock registers after read */ 129 rtc_write( RTC_CONTROLA, ( reg_a & ~RTC_CA_WRITE )); 130 131 return 0; 132 } 133 134 void rtc_reset (void) 135 { 136 uchar reg_a, reg_b; 137 138 reg_a = rtc_read( RTC_CONTROLA ); 139 reg_b = rtc_read( RTC_CONTROLB ); 140 141 if ( reg_b & RTC_CB_OSC_DISABLE ) 142 { 143 printf( "real-time-clock was stopped. Now starting...\n" ); 144 reg_a |= RTC_CA_WRITE; 145 reg_b &= ~RTC_CB_OSC_DISABLE; 146 147 rtc_write( RTC_CONTROLA, reg_a ); 148 rtc_write( RTC_CONTROLB, reg_b ); 149 } 150 151 /* make sure read/write clock register bits are cleared */ 152 reg_a &= ~( RTC_CA_WRITE | RTC_CA_READ ); 153 rtc_write( RTC_CONTROLA, reg_a ); 154 } 155 156 /* ------------------------------------------------------------------------- */ 157 158 static uchar rtc_read( unsigned int addr ) 159 { 160 uchar val = *(volatile unsigned char*)(addr); 161 162 #ifdef RTC_DEBUG 163 printf( "rtc_read: %x:%x\n", addr, val ); 164 #endif 165 return( val ); 166 } 167 168 static void rtc_write( unsigned int addr, uchar val ) 169 { 170 #ifdef RTC_DEBUG 171 printf( "rtc_write: %x:%x\n", addr, val ); 172 #endif 173 *(volatile unsigned char*)(addr) = val; 174 } 175 176 #endif 177