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authorJohn Stultz <johnstul@us.ibm.com>2010-07-13 17:56:27 -0700
committerThomas Gleixner <tglx@linutronix.de>2010-07-27 12:40:55 +0200
commitf12a15be63d1de9a35971f35f06b73088fa25c3a (patch)
tree444084a06e776f005d52d3214fb35b91b3a8345d /arch/x86/kernel/hpet.c
parent0fb86b06298b6cd3205cac2e68a499f269282dac (diff)
downloadlinux-f12a15be63d1de9a35971f35f06b73088fa25c3a.tar.bz2
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.c13
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;
}