diff options
Diffstat (limited to 'rtc/mc146818.c')
| -rw-r--r-- | rtc/mc146818.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/rtc/mc146818.c b/rtc/mc146818.c new file mode 100644 index 0000000..1d65808 --- /dev/null +++ b/rtc/mc146818.c @@ -0,0 +1,172 @@ +/* + * (C) Copyright 2001 + * Denis Peter MPL AG Switzerland. d.peter@mpl.ch + * + * 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 MC146818 (PIXX4) RTC + */ + +/*#define DEBUG*/ + +#include <common.h> +#include <command.h> +#include <rtc.h> + +#if defined(CONFIG_RTC_MC146818) && (CONFIG_COMMANDS & CFG_CMD_DATE) + +static uchar rtc_read (uchar reg); +static void rtc_write (uchar reg, uchar val); +static uchar bin2bcd (unsigned int n); +static unsigned bcd2bin(uchar c); + +#define RTC_PORT_MC146818 CFG_ISA_IO_BASE_ADDRESS + 0x70 +#define RTC_SECONDS 0x00 +#define RTC_SECONDS_ALARM 0x01 +#define RTC_MINUTES 0x02 +#define RTC_MINUTES_ALARM 0x03 +#define RTC_HOURS 0x04 +#define RTC_HOURS_ALARM 0x05 +#define RTC_DAY_OF_WEEK 0x06 +#define RTC_DATE_OF_MONTH 0x07 +#define RTC_MONTH 0x08 +#define RTC_YEAR 0x09 +#define RTC_CONFIG_A 0x0A +#define RTC_CONFIG_B 0x0B +#define RTC_CONFIG_C 0x0C +#define RTC_CONFIG_D 0x0D + + +/* ------------------------------------------------------------------------- */ + +void rtc_get (struct rtc_time *tmp) +{ + uchar sec, min, hour, mday, wday, mon, year; + /* here check if rtc can be accessed */ + while((rtc_read(RTC_CONFIG_A)&0x80)==0x80); + sec = rtc_read (RTC_SECONDS); + min = rtc_read (RTC_MINUTES); + hour = rtc_read (RTC_HOURS); + mday = rtc_read (RTC_DATE_OF_MONTH); + wday = rtc_read (RTC_DAY_OF_WEEK); + mon = rtc_read (RTC_MONTH); + year = rtc_read (RTC_YEAR); +#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 ); + printf ( "Alarms: month: %02x hour: %02x min: %02x sec: %02x\n", + rtc_read (RTC_CONFIG_D) & 0x3F, + rtc_read (RTC_HOURS_ALARM), + rtc_read (RTC_MINUTES_ALARM), + rtc_read (RTC_SECONDS_ALARM) ); +#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_year = bcd2bin (year); + tmp->tm_wday = bcd2bin (wday & 0x07); + if(tmp->tm_year<70) + tmp->tm_year+=2000; + else + tmp->tm_year+=1900; + 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 +} + +void rtc_set (struct rtc_time *tmp) +{ +#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 + rtc_write(RTC_CONFIG_B,0x82); /* disables the RTC to update the regs */ + + rtc_write (RTC_YEAR, bin2bcd(tmp->tm_year % 100)); + rtc_write (RTC_MONTH, bin2bcd(tmp->tm_mon)); + + rtc_write (RTC_DAY_OF_WEEK, bin2bcd(tmp->tm_wday)); + rtc_write (RTC_DATE_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 )); + rtc_write(RTC_CONFIG_B,0x02); /* enables the RTC to update the regs */ + +} + +void rtc_reset (void) +{ + rtc_write(RTC_CONFIG_B,0x82); /* disables the RTC to update the regs */ + rtc_write(RTC_CONFIG_A,0x20); /* Normal OP */ + rtc_write(RTC_CONFIG_B,0x00); + rtc_write(RTC_CONFIG_B,0x00); + rtc_write(RTC_CONFIG_B,0x02); /* enables the RTC to update the regs */ +} + +/* ------------------------------------------------------------------------- */ + +#ifdef CFG_RTC_REG_BASE_ADDR +/* + * use direct memory access + */ +static uchar rtc_read (uchar reg) +{ + return(in8(CFG_RTC_REG_BASE_ADDR+reg)); +} + +static void rtc_write (uchar reg, uchar val) +{ + out8(CFG_RTC_REG_BASE_ADDR+reg, val); +} +#else +static uchar rtc_read (uchar reg) +{ + out8(RTC_PORT_MC146818,reg); + return(in8(RTC_PORT_MC146818+1)); +} + +static void rtc_write (uchar reg, uchar val) +{ + out8(RTC_PORT_MC146818,reg); + out8(RTC_PORT_MC146818+1,val); +} +#endif + +static unsigned bcd2bin (uchar n) +{ + return ((((n >> 4) & 0x0F) * 10) + (n & 0x0F)); +} + +static unsigned char bin2bcd (unsigned int n) +{ + return (((n / 10) << 4) | (n % 10)); +} + +#endif /* CONFIG_RTC_MC146818 && CFG_CMD_DATE */ |