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-rw-r--r--arch/x86_64/Kconfig4
-rw-r--r--arch/x86_64/kernel/time.c25
2 files changed, 13 insertions, 16 deletions
diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig
index 14bf8ce3ea23..fca1a85042ea 100644
--- a/arch/x86_64/Kconfig
+++ b/arch/x86_64/Kconfig
@@ -32,6 +32,10 @@ config GENERIC_TIME_VSYSCALL
bool
default y
+config GENERIC_CMOS_UPDATE
+ bool
+ default y
+
config ZONE_DMA32
bool
default y
diff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c
index 5405a69a1f72..d0e014e4d9c4 100644
--- a/arch/x86_64/kernel/time.c
+++ b/arch/x86_64/kernel/time.c
@@ -80,8 +80,9 @@ EXPORT_SYMBOL(profile_pc);
* sheet for details.
*/
-static void set_rtc_mmss(unsigned long nowtime)
+static int set_rtc_mmss(unsigned long nowtime)
{
+ int retval = 0;
int real_seconds, real_minutes, cmos_minutes;
unsigned char control, freq_select;
@@ -121,6 +122,7 @@ static void set_rtc_mmss(unsigned long nowtime)
if (abs(real_minutes - cmos_minutes) >= 30) {
printk(KERN_WARNING "time.c: can't update CMOS clock "
"from %d to %d\n", cmos_minutes, real_minutes);
+ retval = -1;
} else {
BIN_TO_BCD(real_seconds);
BIN_TO_BCD(real_minutes);
@@ -140,12 +142,17 @@ static void set_rtc_mmss(unsigned long nowtime)
CMOS_WRITE(freq_select, RTC_FREQ_SELECT);
spin_unlock(&rtc_lock);
+
+ return retval;
}
+int update_persistent_clock(struct timespec now)
+{
+ return set_rtc_mmss(now.tv_sec);
+}
void main_timer_handler(void)
{
- static unsigned long rtc_update = 0;
/*
* Here we are in the timer irq handler. We have irqs locally disabled (so we
* don't need spin_lock_irqsave()) but we don't know if the timer_bh is running
@@ -173,20 +180,6 @@ void main_timer_handler(void)
if (!using_apic_timer)
smp_local_timer_interrupt();
-/*
- * If we have an externally synchronized Linux clock, then update CMOS clock
- * accordingly every ~11 minutes. set_rtc_mmss() will be called in the jiffy
- * closest to exactly 500 ms before the next second. If the update fails, we
- * don't care, as it'll be updated on the next turn, and the problem (time way
- * off) isn't likely to go away much sooner anyway.
- */
-
- if (ntp_synced() && xtime.tv_sec > rtc_update &&
- abs(xtime.tv_nsec - 500000000) <= tick_nsec / 2) {
- set_rtc_mmss(xtime.tv_sec);
- rtc_update = xtime.tv_sec + 660;
- }
-
write_sequnlock(&xtime_lock);
}