diff options
Diffstat (limited to 'arch/mips/include/asm/mc146818-time.h')
-rw-r--r-- | arch/mips/include/asm/mc146818-time.h | 105 |
1 files changed, 7 insertions, 98 deletions
diff --git a/arch/mips/include/asm/mc146818-time.h b/arch/mips/include/asm/mc146818-time.h index cbf5cec345f1..ac52a30b4161 100644 --- a/arch/mips/include/asm/mc146818-time.h +++ b/arch/mips/include/asm/mc146818-time.h @@ -8,112 +8,21 @@ #ifndef __ASM_MC146818_TIME_H #define __ASM_MC146818_TIME_H -#include <linux/bcd.h> #include <linux/mc146818rtc.h> #include <linux/time.h> -/* - * For check timing call set_rtc_mmss() 500ms; used in timer interrupt. - */ -#define USEC_AFTER 500000 -#define USEC_BEFORE 500000 - -/* - * In order to set the CMOS clock precisely, set_rtc_mmss has to be - * called 500 ms after the second nowtime has started, because when - * nowtime is written into the registers of the CMOS clock, it will - * jump to the next second precisely 500 ms later. Check the Motorola - * MC146818A or Dallas DS12887 data sheet for details. - * - * BUG: This routine does not handle hour overflow properly; it just - * sets the minutes. Usually you'll only notice that after reboot! - */ -static inline int mc146818_set_rtc_mmss(unsigned long nowtime) -{ - int real_seconds, real_minutes, cmos_minutes; - unsigned char save_control, save_freq_select; - int retval = 0; - unsigned long flags; - - spin_lock_irqsave(&rtc_lock, flags); - save_control = CMOS_READ(RTC_CONTROL); /* tell the clock it's being set */ - CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL); - - save_freq_select = CMOS_READ(RTC_FREQ_SELECT); /* stop and reset prescaler */ - CMOS_WRITE((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT); - - cmos_minutes = CMOS_READ(RTC_MINUTES); - if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) - cmos_minutes = bcd2bin(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) { - if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) { - real_seconds = bin2bcd(real_seconds); - real_minutes = bin2bcd(real_minutes); - } - CMOS_WRITE(real_seconds, RTC_SECONDS); - CMOS_WRITE(real_minutes, RTC_MINUTES); - } else { - printk_once(KERN_NOTICE - "set_rtc_mmss: can't update from %d to %d\n", - cmos_minutes, real_minutes); - retval = -1; - } - - /* The following flags have to be released exactly in this order, - * otherwise the DS12887 (popular MC146818A clone with integrated - * battery and quartz) will not reset the oscillator and will not - * update precisely 500 ms later. You won't find this mentioned in - * the Dallas Semiconductor data sheets, but who believes data - * sheets anyway ... -- Markus Kuhn - */ - CMOS_WRITE(save_control, RTC_CONTROL); - CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT); - spin_unlock_irqrestore(&rtc_lock, flags); - - return retval; -} - +#ifdef CONFIG_RTC_MC146818_LIB static inline time64_t mc146818_get_cmos_time(void) { - unsigned int year, mon, day, hour, min, sec; - unsigned long flags; - - spin_lock_irqsave(&rtc_lock, flags); - - do { - sec = CMOS_READ(RTC_SECONDS); - min = CMOS_READ(RTC_MINUTES); - hour = CMOS_READ(RTC_HOURS); - day = CMOS_READ(RTC_DAY_OF_MONTH); - mon = CMOS_READ(RTC_MONTH); - year = CMOS_READ(RTC_YEAR); - } while (sec != CMOS_READ(RTC_SECONDS)); + struct rtc_time tm; - if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) || RTC_ALWAYS_BCD) { - sec = bcd2bin(sec); - min = bcd2bin(min); - hour = bcd2bin(hour); - day = bcd2bin(day); - mon = bcd2bin(mon); - year = bcd2bin(year); + if (mc146818_get_time(&tm, 1000)) { + pr_err("Unable to read current time from RTC\n"); + return 0; } - spin_unlock_irqrestore(&rtc_lock, flags); - year = mc146818_decode_year(year); - return mktime64(year, mon, day, hour, min, sec); + return rtc_tm_to_time64(&tm); } +#endif /* CONFIG_RTC_MC146818_LIB */ #endif /* __ASM_MC146818_TIME_H */ |