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