diff options
Diffstat (limited to 'arch/x86/kernel/hpet.c')
| -rw-r--r-- | arch/x86/kernel/hpet.c | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c index ba390d73117..351f9c0fea1 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; } |