u-boot/rtc/bf5xx_rtc.c

144 lines
4.4 KiB
C

/*
* (C) Copyright 2001
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* 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
* Real Time Clock interface of ADI21535 (Blackfin) for uCLinux
*
* Copyright (C) 2003 Motorola Corporation. All rights reserved.
* Richard Xiao (A2590C@email.mot.com)
*
* Copyright (C) 1996 Paul Gortmaker
*
*
* Based on other minimal char device drivers, like Alan's
* watchdog, Ted's random, etc. etc.
*
* 1.07 Paul Gortmaker.
* 1.08 Miquel van Smoorenburg: disallow certain things on the
* DEC Alpha as the CMOS clock is also used for other things.
* 1.09 Nikita Schmidt: epoch support and some Alpha cleanup.
* 1.09a Pete Zaitcev: Sun SPARC
* 1.09b Jeff Garzik: Modularize, init cleanup
* 1.09c Jeff Garzik: SMP cleanup
* 1.10 Paul Barton-Davis: add support for async I/O
* 1.10a Andrea Arcangeli: Alpha updates
* 1.10b Andrew Morton: SMP lock fix
* 1.10c Cesar Barros: SMP locking fixes and cleanup
* 1.10d Paul Gortmaker: delete paranoia check in rtc_exit
* 1.10e LG Soft India: Register access is different in BF533.
*/
#include <common.h>
#include <command.h>
#include <rtc.h>
#if defined(CONFIG_RTC_BFIN) && (CONFIG_COMMANDS & CFG_CMD_DATE)
#include <asm/blackfin.h>
#include <asm/arch/bf5xx_rtc.h>
void rtc_reset(void)
{
return; /* nothing to do */
}
/* Wait for pending writes to complete */
void wait_for_complete(void)
{
while (!(*(volatile unsigned short *)RTC_ISTAT & 0x8000)) {
printf("");
}
*(volatile unsigned short *)RTC_ISTAT = 0x8000;
}
/* Enable the RTC prescaler enable register */
void rtc_init()
{
*(volatile unsigned short *)RTC_PREN = 0x1;
wait_for_complete();
}
/* Set the time. Get the time_in_secs which is the number of seconds since Jan 1970 and set the RTC registers
* based on this value.
*/
void rtc_set(struct rtc_time *tmp)
{
unsigned long n_days_1970 = 0;
unsigned long n_secs_rem = 0;
unsigned long n_hrs = 0;
unsigned long n_mins = 0;
unsigned long n_secs = 0;
unsigned long time_in_secs;
if (tmp == NULL) {
printf("Error setting the date/time \n");
return;
}
time_in_secs =
mktime(tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_hour,
tmp->tm_min, tmp->tm_sec);
/* Compute no. of days since 1970 */
n_days_1970 = (unsigned long)(time_in_secs / (NUM_SECS_IN_DAY));
/* From the remining secs, compute the hrs(0-23), mins(0-59) and secs(0-59) */
n_secs_rem = (unsigned long)(time_in_secs % (NUM_SECS_IN_DAY));
n_hrs = n_secs_rem / (NUM_SECS_IN_HOUR);
n_secs_rem = n_secs_rem % (NUM_SECS_IN_HOUR);
n_mins = n_secs_rem / (NUM_SECS_IN_MIN);
n_secs = n_secs_rem % (NUM_SECS_IN_MIN);
/* Store the new time in the RTC_STAT register */
*(volatile unsigned long *)RTC_STAT =
((n_days_1970 << DAY_BITS_OFF) | (n_hrs << HOUR_BITS_OFF) |
(n_mins << MIN_BITS_OFF) | (n_secs << SEC_BITS_OFF));
wait_for_complete();
}
/* Read the time from the RTC_STAT. time_in_seconds is seconds since Jan 1970 */
void rtc_get(struct rtc_time *tmp)
{
unsigned long cur_rtc_stat = 0;
unsigned long time_in_sec;
unsigned long tm_sec = 0, tm_min = 0, tm_hour = 0, tm_day = 0;
if (tmp == NULL) {
printf("Error getting the date/time \n");
return;
}
/* Read the RTC_STAT register */
cur_rtc_stat = *(volatile unsigned long *)RTC_STAT;
/* Get the secs (0-59), mins (0-59), hrs (0-23) and the days since Jan 1970 */
tm_sec = (cur_rtc_stat >> SEC_BITS_OFF) & 0x3f;
tm_min = (cur_rtc_stat >> MIN_BITS_OFF) & 0x3f;
tm_hour = (cur_rtc_stat >> HOUR_BITS_OFF) & 0x1f;
tm_day = (cur_rtc_stat >> DAY_BITS_OFF) & 0x7fff;
/* Calculate the total number of seconds since Jan 1970 */
time_in_sec = (tm_sec) +
MIN_TO_SECS(tm_min) + HRS_TO_SECS(tm_hour) + DAYS_TO_SECS(tm_day);
to_tm(time_in_sec, tmp);
}
#endif /* CONFIG_RTC_BFIN && CFG_CMD_DATE */