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| author |   John Stultz <johnstul@us.ibm.com> | 2010-07-13 17:56:27 -0700 |
|---|---|---|
| committer |   Thomas Gleixner <tglx@linutronix.de> | 2010-07-27 12:40:55 +0200 |
| commit | f12a15be63d1de9a35971f35f06b73088fa25c3a (patch) | |
| tree | 444084a06e776f005d52d3214fb35b91b3a8345d /arch/x86/kernel/hpet.c | |
| parent | timekeeping: Make xtime and wall_to_monotonic static (diff) | |
| download | linux-dev-f12a15be63d1de9a35971f35f06b73088fa25c3a.tar.xz linux-dev-f12a15be63d1de9a35971f35f06b73088fa25c3a.zip | |
x86: Convert common clocksources to use clocksource_register_hz/khz
This converts the most common of the x86 clocksources over to use
clocksource_register_hz/khz.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
LKML-Reference: <1279068988-21864-11-git-send-email-johnstul@us.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/kernel/hpet.c')
| -rw-r--r-- | arch/x86/kernel/hpet.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c index ba390d731175..33dbcc4ec5ff 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 */ @@ -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_NSEC * NSEC_PER_SEC; + do_div(hpet_freq, hpet_period); + clocksource_register_hz(&clocksource_hpet, (u32)hpet_freq); return 0; } |