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-rw-r--r--rtc/mc146818.c172
1 files changed, 172 insertions, 0 deletions
diff --git a/rtc/mc146818.c b/rtc/mc146818.c
new file mode 100644
index 0000000000..1d65808f79
--- /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 */
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