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-rw-r--r--rtc/ds1556.c206
1 files changed, 206 insertions, 0 deletions
diff --git a/rtc/ds1556.c b/rtc/ds1556.c
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--- /dev/null
+++ b/rtc/ds1556.c
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+/*
+ * (C) Copyright 2002
+ * ARIO Data Networks, Inc. dchiu@ariodata.com
+ *
+ * modified for DS1556:
+ * Frank Panno <fpanno@delphintech.com>, Delphin Technology AG
+ *
+ * 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 DS1556 RTC
+ */
+
+/*#define RTC_DEBUG */
+
+#include <common.h>
+#include <command.h>
+#include <rtc.h>
+
+
+#if defined(CONFIG_RTC_DS1556) && (CONFIG_COMMANDS & CFG_CMD_DATE)
+
+static uchar rtc_read( unsigned int addr );
+static void rtc_write( unsigned int addr, uchar val);
+static uchar bin2bcd (unsigned int n);
+static unsigned bcd2bin(uchar c);
+
+#define RTC_BASE ( CFG_NVRAM_SIZE + CFG_NVRAM_BASE_ADDR )
+
+#define RTC_YEAR ( RTC_BASE + 0xf )
+#define RTC_MONTH ( RTC_BASE + 0xe )
+#define RTC_DAY_OF_MONTH ( RTC_BASE + 0xd )
+#define RTC_DAY_OF_WEEK ( RTC_BASE + 0xc )
+#define RTC_HOURS ( RTC_BASE + 0xb )
+#define RTC_MINUTES ( RTC_BASE + 0xa )
+#define RTC_SECONDS ( RTC_BASE + 0x9 )
+#define RTC_CENTURY ( RTC_BASE + 0x8 )
+
+#define RTC_CONTROLA RTC_CENTURY
+#define RTC_CONTROLB RTC_SECONDS
+#define RTC_CONTROLC RTC_BASE
+
+#define RTC_CA_WRITE 0x80
+#define RTC_CA_READ 0x40
+
+#define RTC_CB_OSC_DISABLE 0x80
+
+#define RTC_CC_BATTERY_FLAG 0x10
+#define RTC_CC_FREQ_TEST 0x40
+
+/* ------------------------------------------------------------------------- */
+
+void 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 mon: %02x mday: %02x wday: %02x "
+ "hr: %02x min: %02x sec: %02x\n",
+ year, century, mon, 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
+}
+
+void 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 ));
+}
+
+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 = *(volatile unsigned char*)(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
+ *(volatile unsigned char*)(addr) = val;
+}
+
+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_DS1556 && CFG_CMD_DATE */
generated by cgit v1.1 at 2024-11-23 01:42:34 +0000