From: Matt Mackall Date: Tue, 28 Mar 2006 09:56:05 +0000 (-0800) Subject: [PATCH] RTC: Remove RTC UIP synchronization on MIPS MC146818 X-Git-Tag: v2.6.17-rc1~266 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=da2468b6a81884a696fd6c7ab66dcc62d7233d32;p=linux-2.6 [PATCH] RTC: Remove RTC UIP synchronization on MIPS MC146818 Signed-off-by: Matt Mackall Cc: Ralf Baechle Cc: Alessandro Zummo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/include/asm-mips/mc146818-time.h b/include/asm-mips/mc146818-time.h index 4721486109..41ac8d363c 100644 --- a/include/asm-mips/mc146818-time.h +++ b/include/asm-mips/mc146818-time.h @@ -86,43 +86,14 @@ static inline int mc146818_set_rtc_mmss(unsigned long nowtime) return retval; } -/* - * Returns true if a clock update is in progress - */ -static inline unsigned char rtc_is_updating(void) -{ - unsigned char uip; - unsigned long flags; - - spin_lock_irqsave(&rtc_lock, flags); - uip = (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP); - spin_unlock_irqrestore(&rtc_lock, flags); - return uip; -} - static inline unsigned long mc146818_get_cmos_time(void) { unsigned int year, mon, day, hour, min, sec; - int i; unsigned long flags; - /* - * The Linux interpretation of the CMOS clock register contents: - * When the Update-In-Progress (UIP) flag goes from 1 to 0, the - * RTC registers show the second which has precisely just started. - * Let's hope other operating systems interpret the RTC the same way. - */ - - /* read RTC exactly on falling edge of update flag */ - for (i = 0 ; i < 1000000 ; i++) /* may take up to 1 second... */ - if (rtc_is_updating()) - break; - for (i = 0 ; i < 1000000 ; i++) /* must try at least 2.228 ms */ - if (!rtc_is_updating()) - break; - spin_lock_irqsave(&rtc_lock, flags); - do { /* Isn't this overkill ? UIP above should guarantee consistency */ + + do { sec = CMOS_READ(RTC_SECONDS); min = CMOS_READ(RTC_MINUTES); hour = CMOS_READ(RTC_HOURS);