linux/arch/sh/boards/mach-sh03/rtc.c
Stephen Hemminger 3e5c12409c set_rtc_mmss: show warning message only once
Occasionally the system gets into a state where the CMOS clock has gotten
slightly ahead of current time and the periodic update of RTC fails.  The
message is a nuisance and repeats spamming the log.

  See: http://www.ntp.org/ntpfaq/NTP-s-trbl-spec.htm#Q-LINUX-SET-RTC-MMSS

Rather than just removing the message, make it show only once and reduce
severity since it indicates a normal and non urgent condition.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 08:03:07 -08:00

133 lines
3.9 KiB
C

/*
* linux/arch/sh/boards/sh03/rtc.c -- CTP/PCI-SH03 on-chip RTC support
*
* Copyright (C) 2004 Saito.K & Jeanne(ksaito@interface.co.jp)
*
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/time.h>
#include <linux/bcd.h>
#include <linux/rtc.h>
#include <linux/spinlock.h>
#include <asm/io.h>
#include <asm/rtc.h>
#define RTC_BASE 0xb0000000
#define RTC_SEC1 (RTC_BASE + 0)
#define RTC_SEC10 (RTC_BASE + 1)
#define RTC_MIN1 (RTC_BASE + 2)
#define RTC_MIN10 (RTC_BASE + 3)
#define RTC_HOU1 (RTC_BASE + 4)
#define RTC_HOU10 (RTC_BASE + 5)
#define RTC_WEE1 (RTC_BASE + 6)
#define RTC_DAY1 (RTC_BASE + 7)
#define RTC_DAY10 (RTC_BASE + 8)
#define RTC_MON1 (RTC_BASE + 9)
#define RTC_MON10 (RTC_BASE + 10)
#define RTC_YEA1 (RTC_BASE + 11)
#define RTC_YEA10 (RTC_BASE + 12)
#define RTC_YEA100 (RTC_BASE + 13)
#define RTC_YEA1000 (RTC_BASE + 14)
#define RTC_CTL (RTC_BASE + 15)
#define RTC_BUSY 1
#define RTC_STOP 2
static DEFINE_SPINLOCK(sh03_rtc_lock);
unsigned long get_cmos_time(void)
{
unsigned int year, mon, day, hour, min, sec;
spin_lock(&sh03_rtc_lock);
again:
do {
sec = (__raw_readb(RTC_SEC1) & 0xf) + (__raw_readb(RTC_SEC10) & 0x7) * 10;
min = (__raw_readb(RTC_MIN1) & 0xf) + (__raw_readb(RTC_MIN10) & 0xf) * 10;
hour = (__raw_readb(RTC_HOU1) & 0xf) + (__raw_readb(RTC_HOU10) & 0xf) * 10;
day = (__raw_readb(RTC_DAY1) & 0xf) + (__raw_readb(RTC_DAY10) & 0xf) * 10;
mon = (__raw_readb(RTC_MON1) & 0xf) + (__raw_readb(RTC_MON10) & 0xf) * 10;
year = (__raw_readb(RTC_YEA1) & 0xf) + (__raw_readb(RTC_YEA10) & 0xf) * 10
+ (__raw_readb(RTC_YEA100 ) & 0xf) * 100
+ (__raw_readb(RTC_YEA1000) & 0xf) * 1000;
} while (sec != (__raw_readb(RTC_SEC1) & 0xf) + (__raw_readb(RTC_SEC10) & 0x7) * 10);
if (year == 0 || mon < 1 || mon > 12 || day > 31 || day < 1 ||
hour > 23 || min > 59 || sec > 59) {
printk(KERN_ERR
"SH-03 RTC: invalid value, resetting to 1 Jan 2000\n");
printk("year=%d, mon=%d, day=%d, hour=%d, min=%d, sec=%d\n",
year, mon, day, hour, min, sec);
__raw_writeb(0, RTC_SEC1); __raw_writeb(0, RTC_SEC10);
__raw_writeb(0, RTC_MIN1); __raw_writeb(0, RTC_MIN10);
__raw_writeb(0, RTC_HOU1); __raw_writeb(0, RTC_HOU10);
__raw_writeb(6, RTC_WEE1);
__raw_writeb(1, RTC_DAY1); __raw_writeb(0, RTC_DAY10);
__raw_writeb(1, RTC_MON1); __raw_writeb(0, RTC_MON10);
__raw_writeb(0, RTC_YEA1); __raw_writeb(0, RTC_YEA10);
__raw_writeb(0, RTC_YEA100);
__raw_writeb(2, RTC_YEA1000);
__raw_writeb(0, RTC_CTL);
goto again;
}
spin_unlock(&sh03_rtc_lock);
return mktime(year, mon, day, hour, min, sec);
}
void sh03_rtc_gettimeofday(struct timespec *tv)
{
tv->tv_sec = get_cmos_time();
tv->tv_nsec = 0;
}
static int set_rtc_mmss(unsigned long nowtime)
{
int retval = 0;
int real_seconds, real_minutes, cmos_minutes;
int i;
/* gets recalled with irq locally disabled */
spin_lock(&sh03_rtc_lock);
for (i = 0 ; i < 1000000 ; i++) /* may take up to 1 second... */
if (!(__raw_readb(RTC_CTL) & RTC_BUSY))
break;
cmos_minutes = (__raw_readb(RTC_MIN1) & 0xf) + (__raw_readb(RTC_MIN10) & 0xf) * 10;
real_seconds = nowtime % 60;
real_minutes = nowtime / 60;
if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1)
real_minutes += 30; /* correct for half hour time zone */
real_minutes %= 60;
if (abs(real_minutes - cmos_minutes) < 30) {
__raw_writeb(real_seconds % 10, RTC_SEC1);
__raw_writeb(real_seconds / 10, RTC_SEC10);
__raw_writeb(real_minutes % 10, RTC_MIN1);
__raw_writeb(real_minutes / 10, RTC_MIN10);
} else {
printk_once(KERN_NOTICE
"set_rtc_mmss: can't update from %d to %d\n",
cmos_minutes, real_minutes);
retval = -1;
}
spin_unlock(&sh03_rtc_lock);
return retval;
}
int sh03_rtc_settimeofday(const time_t secs)
{
unsigned long nowtime = secs;
return set_rtc_mmss(nowtime);
}
void sh03_time_init(void)
{
rtc_sh_get_time = sh03_rtc_gettimeofday;
rtc_sh_set_time = sh03_rtc_settimeofday;
}