1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * (C) Copyright 2002 4 * ARIO Data Networks, Inc. dchiu@ariodata.com 5 * 6 * modified for DS164x: 7 * The LEOX team <team@leox.org>, http://www.leox.org 8 * 9 * Based on MontaVista DS1743 code and U-Boot mc146818 code 10 */ 11 12 /* 13 * Date & Time support for the DS164x RTC 14 */ 15 16 /* #define RTC_DEBUG */ 17 18 #include <common.h> 19 #include <command.h> 20 #include <rtc.h> 21 22 23 #if defined(CONFIG_CMD_DATE) 24 25 static uchar rtc_read(unsigned int addr ); 26 static void rtc_write(unsigned int addr, uchar val); 27 28 #define RTC_EPOCH 2000 /* century */ 29 30 /* 31 * DS164x registers layout 32 */ 33 #define RTC_BASE ( CONFIG_SYS_NVRAM_BASE_ADDR + CONFIG_SYS_NVRAM_SIZE ) 34 35 #define RTC_YEAR ( RTC_BASE + 0x07 ) 36 #define RTC_MONTH ( RTC_BASE + 0x06 ) 37 #define RTC_DAY_OF_MONTH ( RTC_BASE + 0x05 ) 38 #define RTC_DAY_OF_WEEK ( RTC_BASE + 0x04 ) 39 #define RTC_HOURS ( RTC_BASE + 0x03 ) 40 #define RTC_MINUTES ( RTC_BASE + 0x02 ) 41 #define RTC_SECONDS ( RTC_BASE + 0x01 ) 42 #define RTC_CONTROL ( RTC_BASE + 0x00 ) 43 44 #define RTC_CONTROLA RTC_CONTROL /* W=bit6, R=bit5 */ 45 #define RTC_CA_WRITE 0x80 46 #define RTC_CA_READ 0x40 47 #define RTC_CONTROLB RTC_SECONDS /* OSC=bit7 */ 48 #define RTC_CB_OSC_DISABLE 0x80 49 #define RTC_CONTROLC RTC_DAY_OF_WEEK /* FT=bit6 */ 50 #define RTC_CC_FREQ_TEST 0x40 51 52 /* ------------------------------------------------------------------------- */ 53 54 int rtc_get( struct rtc_time *tmp ) 55 { 56 uchar sec, min, hour; 57 uchar mday, wday, mon, year; 58 59 uchar reg_a; 60 61 reg_a = rtc_read( RTC_CONTROLA ); 62 /* lock clock registers for read */ 63 rtc_write( RTC_CONTROLA, ( reg_a | RTC_CA_READ )); 64 65 sec = rtc_read( RTC_SECONDS ); 66 min = rtc_read( RTC_MINUTES ); 67 hour = rtc_read( RTC_HOURS ); 68 mday = rtc_read( RTC_DAY_OF_MONTH ); 69 wday = rtc_read( RTC_DAY_OF_WEEK ); 70 mon = rtc_read( RTC_MONTH ); 71 year = rtc_read( RTC_YEAR ); 72 73 /* unlock clock registers after read */ 74 rtc_write( RTC_CONTROLA, ( reg_a & ~RTC_CA_READ )); 75 76 #ifdef RTC_DEBUG 77 printf( "Get RTC year: %02x mon: %02x mday: %02x wday: %02x " 78 "hr: %02x min: %02x sec: %02x\n", 79 year, mon, mday, wday, 80 hour, min, sec ); 81 #endif 82 tmp->tm_sec = bcd2bin( sec & 0x7F ); 83 tmp->tm_min = bcd2bin( min & 0x7F ); 84 tmp->tm_hour = bcd2bin( hour & 0x3F ); 85 tmp->tm_mday = bcd2bin( mday & 0x3F ); 86 tmp->tm_mon = bcd2bin( mon & 0x1F ); 87 tmp->tm_wday = bcd2bin( wday & 0x07 ); 88 89 /* glue year in century (2000) */ 90 tmp->tm_year = bcd2bin( year ) + RTC_EPOCH; 91 92 tmp->tm_yday = 0; 93 tmp->tm_isdst= 0; 94 #ifdef RTC_DEBUG 95 printf( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 96 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 97 tmp->tm_hour, tmp->tm_min, tmp->tm_sec ); 98 #endif 99 100 return 0; 101 } 102 103 int rtc_set( struct rtc_time *tmp ) 104 { 105 uchar reg_a; 106 107 #ifdef RTC_DEBUG 108 printf( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 109 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 110 tmp->tm_hour, tmp->tm_min, tmp->tm_sec); 111 #endif 112 /* lock clock registers for write */ 113 reg_a = rtc_read( RTC_CONTROLA ); 114 rtc_write( RTC_CONTROLA, ( reg_a | RTC_CA_WRITE )); 115 116 rtc_write( RTC_MONTH, bin2bcd( tmp->tm_mon )); 117 118 rtc_write( RTC_DAY_OF_WEEK, bin2bcd( tmp->tm_wday )); 119 rtc_write( RTC_DAY_OF_MONTH, bin2bcd( tmp->tm_mday )); 120 rtc_write( RTC_HOURS, bin2bcd( tmp->tm_hour )); 121 rtc_write( RTC_MINUTES, bin2bcd( tmp->tm_min )); 122 rtc_write( RTC_SECONDS, bin2bcd( tmp->tm_sec )); 123 124 /* break year in century */ 125 rtc_write( RTC_YEAR, bin2bcd( tmp->tm_year % 100 )); 126 127 /* unlock clock registers after read */ 128 rtc_write( RTC_CONTROLA, ( reg_a & ~RTC_CA_WRITE )); 129 130 return 0; 131 } 132 133 void rtc_reset (void) 134 { 135 uchar reg_a, reg_b; 136 137 reg_a = rtc_read( RTC_CONTROLA ); 138 reg_b = rtc_read( RTC_CONTROLB ); 139 140 if ( reg_b & RTC_CB_OSC_DISABLE ) 141 { 142 printf( "real-time-clock was stopped. Now starting...\n" ); 143 reg_a |= RTC_CA_WRITE; 144 reg_b &= ~RTC_CB_OSC_DISABLE; 145 146 rtc_write( RTC_CONTROLA, reg_a ); 147 rtc_write( RTC_CONTROLB, reg_b ); 148 } 149 150 /* make sure read/write clock register bits are cleared */ 151 reg_a &= ~( RTC_CA_WRITE | RTC_CA_READ ); 152 rtc_write( RTC_CONTROLA, reg_a ); 153 } 154 155 /* ------------------------------------------------------------------------- */ 156 157 static uchar rtc_read( unsigned int addr ) 158 { 159 uchar val = *(volatile unsigned char*)(addr); 160 161 #ifdef RTC_DEBUG 162 printf( "rtc_read: %x:%x\n", addr, val ); 163 #endif 164 return( val ); 165 } 166 167 static void rtc_write( unsigned int addr, uchar val ) 168 { 169 #ifdef RTC_DEBUG 170 printf( "rtc_write: %x:%x\n", addr, val ); 171 #endif 172 *(volatile unsigned char*)(addr) = val; 173 } 174 175 #endif 176