linux 2.6.16.38 w/ vs2.0.3-rc1

[linux-2.6.git] / arch / mips / dec / time.c

diff --git a/arch/mips/dec/time.c b/arch/mips/dec/time.c
index dc7091c..1748223 100644 (file)
--- a/arch/mips/dec/time.c
+++ b/arch/mips/dec/time.c
@@ -37,10 +37,25 @@
 #include <asm/dec/machtype.h>
 
 
+/*
+ * Returns true if a clock update is in progress
+ */
+static inline unsigned char dec_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 unsigned long dec_rtc_get_time(void)
 {
        unsigned int year, mon, day, hour, min, sec, real_year;
        int i;
+       unsigned long flags;
 
        /* The Linux interpretation of the DS1287 clock register contents:
         * When the Update-In-Progress (UIP) flag goes from 1 to 0, the
@@ -49,11 +64,12 @@ static unsigned long dec_rtc_get_time(void)
         */
        /* read RTC exactly on falling edge of update flag */
        for (i = 0; i < 1000000; i++)   /* may take up to 1 second... */
-               if (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP)
+               if (dec_rtc_is_updating())
                        break;
        for (i = 0; i < 1000000; i++)   /* must try at least 2.228 ms */
-               if (!(CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP))
+               if (!dec_rtc_is_updating())
                        break;
+       spin_lock_irqsave(&rtc_lock, flags);
        /* Isn't this overkill?  UIP above should guarantee consistency */
        do {
                sec = CMOS_READ(RTC_SECONDS);
@@ -77,6 +93,7 @@ static unsigned long dec_rtc_get_time(void)
         * of unused BBU RAM locations.
         */
        real_year = CMOS_READ(RTC_DEC_YEAR);
+       spin_unlock_irqrestore(&rtc_lock, flags);
        year += real_year - 72 + 2000;
 
        return mktime(year, mon, day, hour, min, sec);
@@ -95,6 +112,8 @@ static int dec_rtc_set_mmss(unsigned long nowtime)
        int real_seconds, real_minutes, cmos_minutes;
        unsigned char save_control, save_freq_select;
 
+       /* irq are locally disabled here */
+       spin_lock(&rtc_lock);
        /* tell the clock it's being set */
        save_control = CMOS_READ(RTC_CONTROL);
        CMOS_WRITE((save_control | RTC_SET), RTC_CONTROL);
@@ -141,6 +160,7 @@ static int dec_rtc_set_mmss(unsigned long nowtime)
         */
        CMOS_WRITE(save_control, RTC_CONTROL);
        CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
+       spin_unlock(&rtc_lock);
 
        return retval;
 }