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/*
* linux/arch/sh/kernel/rtc.c -- SH3 / SH4 on-chip RTC support
*
* Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
* Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/time.h>
#include <asm/io.h>
#include <asm/rtc.h>
#ifndef BCD_TO_BIN
#define BCD_TO_BIN(val) ((val)=((val)&15) + ((val)>>4)*10)
#endif
#ifndef BIN_TO_BCD
#define BIN_TO_BCD(val) ((val)=(((val)/10)<<4) + (val)%10)
#endif
void sh_rtc_gettimeofday(struct timeval *tv)
{
unsigned int sec128, sec, min, hr, wk, day, mon, yr, yr100;
again:
do {
ctrl_outb(0, RCR1); /* Clear CF-bit */
sec128 = ctrl_inb(R64CNT);
sec = ctrl_inb(RSECCNT);
min = ctrl_inb(RMINCNT);
hr = ctrl_inb(RHRCNT);
wk = ctrl_inb(RWKCNT);
day = ctrl_inb(RDAYCNT);
mon = ctrl_inb(RMONCNT);
#if defined(__SH4__)
yr = ctrl_inw(RYRCNT);
yr100 = (yr >> 8);
yr &= 0xff;
#else
yr = ctrl_inb(RYRCNT);
yr100 = (yr == 0x99) ? 0x19 : 0x20;
#endif
} while ((ctrl_inb(RCR1) & RCR1_CF) != 0);
#if RTC_BIT_INVERTED != 0
/* Work around to avoid reading incorrect value. */
if (sec128 == RTC_BIT_INVERTED) {
schedule_timeout(1);
goto again;
}
#endif
BCD_TO_BIN(yr100);
BCD_TO_BIN(yr);
BCD_TO_BIN(mon);
BCD_TO_BIN(day);
BCD_TO_BIN(hr);
BCD_TO_BIN(min);
BCD_TO_BIN(sec);
if (yr > 99 || mon < 1 || mon > 12 || day > 31 || day < 1 ||
hr > 23 || min > 59 || sec > 59) {
printk(KERN_ERR
"SH RTC: invalid value, resetting to 1 Jan 2000\n");
ctrl_outb(RCR2_RESET, RCR2); /* Reset & Stop */
ctrl_outb(0, RSECCNT);
ctrl_outb(0, RMINCNT);
ctrl_outb(0, RHRCNT);
ctrl_outb(6, RWKCNT);
ctrl_outb(1, RDAYCNT);
ctrl_outb(1, RMONCNT);
#if defined(__SH4__)
ctrl_outw(0x2000, RYRCNT);
#else
ctrl_outb(0, RYRCNT);
#endif
ctrl_outb(RCR2_RTCEN|RCR2_START, RCR2); /* Start */
goto again;
}
#if RTC_BIT_INVERTED != 0
if ((sec128 & RTC_BIT_INVERTED))
sec--;
#endif
tv->tv_sec = mktime(yr100 * 100 + yr, mon, day, hr, min, sec);
tv->tv_usec = (sec128 * 1000000) / 128;
}
int sh_rtc_settimeofday(const struct timeval *tv)
{
unsigned long nowtime = tv->tv_sec;
int retval = 0;
int real_seconds, real_minutes, cmos_minutes;
ctrl_outb(RCR2_RESET, RCR2); /* Reset pre-scaler & stop RTC */
cmos_minutes = ctrl_inb(RMINCNT);
BCD_TO_BIN(cmos_minutes);
/*
* since we're only adjusting minutes and seconds,
* don't interfere with hour overflow. This avoids
* messing with unknown time zones but requires your
* RTC not to be off by more than 15 minutes
*/
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) {
BIN_TO_BCD(real_seconds);
BIN_TO_BCD(real_minutes);
ctrl_outb(real_seconds, RSECCNT);
ctrl_outb(real_minutes, RMINCNT);
} else {
printk(KERN_WARNING
"set_rtc_time: can't update from %d to %d\n",
cmos_minutes, real_minutes);
retval = -1;
}
ctrl_outb(RCR2_RTCEN|RCR2_START, RCR2); /* Start RTC */
return retval;
}
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