1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * (C) Copyright 2002 4 * ARIO Data Networks, Inc. dchiu@ariodata.com 5 * 6 * modified for DS1556: 7 * Frank Panno <fpanno@delphintech.com>, Delphin Technology AG 8 * 9 * Based on MontaVista DS1743 code and U-Boot mc146818 code 10 */ 11 12 /* 13 * Date & Time support for the DS1556 RTC 14 */ 15 16 /*#define RTC_DEBUG */ 17 18 #include <common.h> 19 #include <command.h> 20 #include <rtc.h> 21 22 #if defined(CONFIG_CMD_DATE) 23 24 static uchar rtc_read( unsigned int addr ); 25 static void rtc_write( unsigned int addr, uchar val); 26 27 #define RTC_BASE ( CONFIG_SYS_NVRAM_SIZE + CONFIG_SYS_NVRAM_BASE_ADDR ) 28 29 #define RTC_YEAR ( RTC_BASE + 0xf ) 30 #define RTC_MONTH ( RTC_BASE + 0xe ) 31 #define RTC_DAY_OF_MONTH ( RTC_BASE + 0xd ) 32 #define RTC_DAY_OF_WEEK ( RTC_BASE + 0xc ) 33 #define RTC_HOURS ( RTC_BASE + 0xb ) 34 #define RTC_MINUTES ( RTC_BASE + 0xa ) 35 #define RTC_SECONDS ( RTC_BASE + 0x9 ) 36 #define RTC_CENTURY ( RTC_BASE + 0x8 ) 37 38 #define RTC_CONTROLA RTC_CENTURY 39 #define RTC_CONTROLB RTC_SECONDS 40 #define RTC_CONTROLC RTC_BASE 41 42 #define RTC_CA_WRITE 0x80 43 #define RTC_CA_READ 0x40 44 45 #define RTC_CB_OSC_DISABLE 0x80 46 47 #define RTC_CC_BATTERY_FLAG 0x10 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 int century; 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 century = rtc_read( RTC_CENTURY ); 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/cent: %02x mon: %02x mday: %02x wday: %02x " 79 "hr: %02x min: %02x sec: %02x\n", 80 year, century, 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 from century and year in century */ 91 tmp->tm_year = bcd2bin( year ) + 92 ( bcd2bin( century & 0x3F ) * 100 ); 93 94 tmp->tm_yday = 0; 95 tmp->tm_isdst= 0; 96 #ifdef RTC_DEBUG 97 printf( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", 98 tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, 99 tmp->tm_hour, tmp->tm_min, tmp->tm_sec ); 100 #endif 101 return 0; 102 } 103 104 int rtc_set( struct rtc_time *tmp ) 105 { 106 uchar reg_a; 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 up into century and year in century */ 125 rtc_write( RTC_YEAR, bin2bcd( tmp->tm_year % 100 )); 126 rtc_write( RTC_CENTURY, 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, reg_c; 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 reg_c = rtc_read( RTC_CONTROLC ); 156 if (( reg_c & RTC_CC_BATTERY_FLAG ) == 0 ) 157 printf( "RTC battery low. Clock setting may not be reliable.\n" ); 158 } 159 160 /* ------------------------------------------------------------------------- */ 161 162 static uchar rtc_read( unsigned int addr ) 163 { 164 uchar val = *(volatile unsigned char*)(addr); 165 #ifdef RTC_DEBUG 166 printf( "rtc_read: %x:%x\n", addr, val ); 167 #endif 168 return( val ); 169 } 170 171 static void rtc_write( unsigned int addr, uchar val ) 172 { 173 #ifdef RTC_DEBUG 174 printf( "rtc_write: %x:%x\n", addr, val ); 175 #endif 176 *(volatile unsigned char*)(addr) = val; 177 } 178 179 #endif 180