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Diffstat (limited to 'arch/i386/kernel/time_hpet.c')
-rw-r--r--arch/i386/kernel/time_hpet.c20
1 files changed, 11 insertions, 9 deletions
diff --git a/arch/i386/kernel/time_hpet.c b/arch/i386/kernel/time_hpet.c
index 658c0629ba6..9caeaa315cd 100644
--- a/arch/i386/kernel/time_hpet.c
+++ b/arch/i386/kernel/time_hpet.c
@@ -275,6 +275,7 @@ static unsigned long PIE_freq = DEFAULT_RTC_INT_FREQ;
static unsigned long PIE_count;
static unsigned long hpet_rtc_int_freq; /* RTC interrupt frequency */
+static unsigned int hpet_t1_cmp; /* cached comparator register */
/*
* Timer 1 for RTC, we do not use periodic interrupt feature,
@@ -306,10 +307,12 @@ int hpet_rtc_timer_init(void)
cnt = hpet_readl(HPET_COUNTER);
cnt += ((hpet_tick*HZ)/hpet_rtc_int_freq);
hpet_writel(cnt, HPET_T1_CMP);
+ hpet_t1_cmp = cnt;
local_irq_restore(flags);
cfg = hpet_readl(HPET_T1_CFG);
- cfg |= HPET_TN_ENABLE | HPET_TN_SETVAL | HPET_TN_32BIT;
+ cfg &= ~HPET_TN_PERIODIC;
+ cfg |= HPET_TN_ENABLE | HPET_TN_32BIT;
hpet_writel(cfg, HPET_T1_CFG);
return 1;
@@ -319,8 +322,12 @@ static void hpet_rtc_timer_reinit(void)
{
unsigned int cfg, cnt;
- if (!(PIE_on | AIE_on | UIE_on))
+ if (unlikely(!(PIE_on | AIE_on | UIE_on))) {
+ cfg = hpet_readl(HPET_T1_CFG);
+ cfg &= ~HPET_TN_ENABLE;
+ hpet_writel(cfg, HPET_T1_CFG);
return;
+ }
if (PIE_on && (PIE_freq > DEFAULT_RTC_INT_FREQ))
hpet_rtc_int_freq = PIE_freq;
@@ -328,15 +335,10 @@ static void hpet_rtc_timer_reinit(void)
hpet_rtc_int_freq = DEFAULT_RTC_INT_FREQ;
/* It is more accurate to use the comparator value than current count.*/
- cnt = hpet_readl(HPET_T1_CMP);
+ cnt = hpet_t1_cmp;
cnt += hpet_tick*HZ/hpet_rtc_int_freq;
hpet_writel(cnt, HPET_T1_CMP);
-
- cfg = hpet_readl(HPET_T1_CFG);
- cfg |= HPET_TN_ENABLE | HPET_TN_SETVAL | HPET_TN_32BIT;
- hpet_writel(cfg, HPET_T1_CFG);
-
- return;
+ hpet_t1_cmp = cnt;
}
/*