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-rw-r--r--arch/x86/kernel/hpet.c15
1 files changed, 10 insertions, 5 deletions
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index ba390d731175..351f9c0fea1f 100644
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -16,7 +16,6 @@
#include <asm/hpet.h>
#define HPET_MASK CLOCKSOURCE_MASK(32)
-#define HPET_SHIFT 22
/* FSEC = 10^-15
NSEC = 10^-9 */
@@ -583,7 +582,7 @@ static void init_one_hpet_msi_clockevent(struct hpet_dev *hdev, int cpu)
* scaled math multiplication factor for nanosecond to hpet tick
* conversion.
*/
- hpet_freq = 1000000000000000ULL;
+ hpet_freq = FSEC_PER_SEC;
do_div(hpet_freq, hpet_period);
evt->mult = div_sc((unsigned long) hpet_freq,
NSEC_PER_SEC, evt->shift);
@@ -787,7 +786,6 @@ static struct clocksource clocksource_hpet = {
.rating = 250,
.read = read_hpet,
.mask = HPET_MASK,
- .shift = HPET_SHIFT,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
.resume = hpet_resume_counter,
#ifdef CONFIG_X86_64
@@ -798,6 +796,7 @@ static struct clocksource clocksource_hpet = {
static int hpet_clocksource_register(void)
{
u64 start, now;
+ u64 hpet_freq;
cycle_t t1;
/* Start the counter */
@@ -832,9 +831,15 @@ static int hpet_clocksource_register(void)
* mult = (hpet_period * 2^shift)/10^6
* mult = (hpet_period << shift)/FSEC_PER_NSEC
*/
- clocksource_hpet.mult = div_sc(hpet_period, FSEC_PER_NSEC, HPET_SHIFT);
- clocksource_register(&clocksource_hpet);
+ /* Need to convert hpet_period (fsec/cyc) to cyc/sec:
+ *
+ * cyc/sec = FSEC_PER_SEC/hpet_period(fsec/cyc)
+ * cyc/sec = (FSEC_PER_NSEC * NSEC_PER_SEC)/hpet_period
+ */
+ hpet_freq = FSEC_PER_SEC;
+ do_div(hpet_freq, hpet_period);
+ clocksource_register_hz(&clocksource_hpet, (u32)hpet_freq);
return 0;
}