/* * (C) Copyright 2001 * ARIO Data Networks, Inc. dchiu@ariodata.com * * Based on MontaVista DS1743 code and U-Boot mc146818 code * * See file CREDITS for list of people who contributed to this * project. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of * the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA */ /* * Date & Time support for the DS174x RTC */ /*#define DEBUG*/ #include <common.h> #include <command.h> #include <rtc.h> #if defined(CONFIG_CMD_DATE) static uchar rtc_read( unsigned int addr ); static void rtc_write( unsigned int addr, uchar val); #define RTC_BASE ( CONFIG_SYS_NVRAM_SIZE + CONFIG_SYS_NVRAM_BASE_ADDR ) #define RTC_YEAR ( RTC_BASE + 7 ) #define RTC_MONTH ( RTC_BASE + 6 ) #define RTC_DAY_OF_MONTH ( RTC_BASE + 5 ) #define RTC_DAY_OF_WEEK ( RTC_BASE + 4 ) #define RTC_HOURS ( RTC_BASE + 3 ) #define RTC_MINUTES ( RTC_BASE + 2 ) #define RTC_SECONDS ( RTC_BASE + 1 ) #define RTC_CENTURY ( RTC_BASE + 0 ) #define RTC_CONTROLA RTC_CENTURY #define RTC_CONTROLB RTC_SECONDS #define RTC_CONTROLC RTC_DAY_OF_WEEK #define RTC_CA_WRITE 0x80 #define RTC_CA_READ 0x40 #define RTC_CB_OSC_DISABLE 0x80 #define RTC_CC_BATTERY_FLAG 0x80 #define RTC_CC_FREQ_TEST 0x40 /* ------------------------------------------------------------------------- */ int rtc_get( struct rtc_time *tmp ) { uchar sec, min, hour; uchar mday, wday, mon, year; int century; uchar reg_a; reg_a = rtc_read( RTC_CONTROLA ); /* lock clock registers for read */ rtc_write( RTC_CONTROLA, ( reg_a | RTC_CA_READ )); sec = rtc_read( RTC_SECONDS ); min = rtc_read( RTC_MINUTES ); hour = rtc_read( RTC_HOURS ); mday = rtc_read( RTC_DAY_OF_MONTH ); wday = rtc_read( RTC_DAY_OF_WEEK ); mon = rtc_read( RTC_MONTH ); year = rtc_read( RTC_YEAR ); century = rtc_read( RTC_CENTURY ); /* unlock clock registers after read */ rtc_write( RTC_CONTROLA, ( reg_a & ~RTC_CA_READ )); #ifdef RTC_DEBUG printf( "Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x " "hr: %02x min: %02x sec: %02x\n", year, mon_cent, mday, wday, hour, min, sec ); #endif tmp->tm_sec = bcd2bin( sec & 0x7F ); tmp->tm_min = bcd2bin( min & 0x7F ); tmp->tm_hour = bcd2bin( hour & 0x3F ); tmp->tm_mday = bcd2bin( mday & 0x3F ); tmp->tm_mon = bcd2bin( mon & 0x1F ); tmp->tm_wday = bcd2bin( wday & 0x07 ); /* glue year from century and year in century */ tmp->tm_year = bcd2bin( year ) + ( bcd2bin( century & 0x3F ) * 100 ); tmp->tm_yday = 0; tmp->tm_isdst= 0; #ifdef RTC_DEBUG printf( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, tmp->tm_hour, tmp->tm_min, tmp->tm_sec ); #endif return 0; } int rtc_set( struct rtc_time *tmp ) { uchar reg_a; #ifdef RTC_DEBUG printf( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, tmp->tm_hour, tmp->tm_min, tmp->tm_sec); #endif /* lock clock registers for write */ reg_a = rtc_read( RTC_CONTROLA ); rtc_write( RTC_CONTROLA, ( reg_a | RTC_CA_WRITE )); rtc_write( RTC_MONTH, bin2bcd( tmp->tm_mon )); rtc_write( RTC_DAY_OF_WEEK, bin2bcd( tmp->tm_wday )); rtc_write( RTC_DAY_OF_MONTH, bin2bcd( tmp->tm_mday )); rtc_write( RTC_HOURS, bin2bcd( tmp->tm_hour )); rtc_write( RTC_MINUTES, bin2bcd( tmp->tm_min )); rtc_write( RTC_SECONDS, bin2bcd( tmp->tm_sec )); /* break year up into century and year in century */ rtc_write( RTC_YEAR, bin2bcd( tmp->tm_year % 100 )); rtc_write( RTC_CENTURY, bin2bcd( tmp->tm_year / 100 )); /* unlock clock registers after read */ rtc_write( RTC_CONTROLA, ( reg_a & ~RTC_CA_WRITE )); return 0; } void rtc_reset (void) { uchar reg_a, reg_b, reg_c; reg_a = rtc_read( RTC_CONTROLA ); reg_b = rtc_read( RTC_CONTROLB ); if ( reg_b & RTC_CB_OSC_DISABLE ) { printf( "real-time-clock was stopped. Now starting...\n" ); reg_a |= RTC_CA_WRITE; reg_b &= ~RTC_CB_OSC_DISABLE; rtc_write( RTC_CONTROLA, reg_a ); rtc_write( RTC_CONTROLB, reg_b ); } /* make sure read/write clock register bits are cleared */ reg_a &= ~( RTC_CA_WRITE | RTC_CA_READ ); rtc_write( RTC_CONTROLA, reg_a ); reg_c = rtc_read( RTC_CONTROLC ); if (( reg_c & RTC_CC_BATTERY_FLAG ) == 0 ) printf( "RTC battery low. Clock setting may not be reliable.\n" ); } /* ------------------------------------------------------------------------- */ static uchar rtc_read( unsigned int addr ) { uchar val = in8( addr ); #ifdef RTC_DEBUG printf( "rtc_read: %x:%x\n", addr, val ); #endif return( val ); } static void rtc_write( unsigned int addr, uchar val ) { #ifdef RTC_DEBUG printf( "rtc_write: %x:%x\n", addr, val ); #endif out8( addr, val ); } #endif