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-rw-r--r--arch/powerpc/kernel/time.c107
1 files changed, 31 insertions, 76 deletions
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 03b29a6759ab..567dd7c3ac2a 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -33,7 +33,7 @@
*/
#include <linux/errno.h>
-#include <linux/module.h>
+#include <linux/export.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/param.h>
@@ -86,8 +86,6 @@ static struct clocksource clocksource_rtc = {
.rating = 400,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
.mask = CLOCKSOURCE_MASK(64),
- .shift = 22,
- .mult = 0, /* To be filled in */
.read = rtc_read,
};
@@ -97,8 +95,6 @@ static struct clocksource clocksource_timebase = {
.rating = 400,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
.mask = CLOCKSOURCE_MASK(64),
- .shift = 22,
- .mult = 0, /* To be filled in */
.read = timebase_read,
};
@@ -110,22 +106,16 @@ static void decrementer_set_mode(enum clock_event_mode mode,
struct clock_event_device *dev);
static struct clock_event_device decrementer_clockevent = {
- .name = "decrementer",
- .rating = 200,
- .shift = 0, /* To be filled in */
- .mult = 0, /* To be filled in */
- .irq = 0,
- .set_next_event = decrementer_set_next_event,
- .set_mode = decrementer_set_mode,
- .features = CLOCK_EVT_FEAT_ONESHOT,
+ .name = "decrementer",
+ .rating = 200,
+ .irq = 0,
+ .set_next_event = decrementer_set_next_event,
+ .set_mode = decrementer_set_mode,
+ .features = CLOCK_EVT_FEAT_ONESHOT,
};
-struct decrementer_clock {
- struct clock_event_device event;
- u64 next_tb;
-};
-
-static DEFINE_PER_CPU(struct decrementer_clock, decrementers);
+DEFINE_PER_CPU(u64, decrementers_next_tb);
+static DEFINE_PER_CPU(struct clock_event_device, decrementers);
#ifdef CONFIG_PPC_ISERIES
static unsigned long __initdata iSeries_recal_titan;
@@ -168,13 +158,13 @@ EXPORT_SYMBOL_GPL(ppc_tb_freq);
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
/*
* Factors for converting from cputime_t (timebase ticks) to
- * jiffies, milliseconds, seconds, and clock_t (1/USER_HZ seconds).
+ * jiffies, microseconds, seconds, and clock_t (1/USER_HZ seconds).
* These are all stored as 0.64 fixed-point binary fractions.
*/
u64 __cputime_jiffies_factor;
EXPORT_SYMBOL(__cputime_jiffies_factor);
-u64 __cputime_msec_factor;
-EXPORT_SYMBOL(__cputime_msec_factor);
+u64 __cputime_usec_factor;
+EXPORT_SYMBOL(__cputime_usec_factor);
u64 __cputime_sec_factor;
EXPORT_SYMBOL(__cputime_sec_factor);
u64 __cputime_clockt_factor;
@@ -192,8 +182,8 @@ static void calc_cputime_factors(void)
div128_by_32(HZ, 0, tb_ticks_per_sec, &res);
__cputime_jiffies_factor = res.result_low;
- div128_by_32(1000, 0, tb_ticks_per_sec, &res);
- __cputime_msec_factor = res.result_low;
+ div128_by_32(1000000, 0, tb_ticks_per_sec, &res);
+ __cputime_usec_factor = res.result_low;
div128_by_32(1, 0, tb_ticks_per_sec, &res);
__cputime_sec_factor = res.result_low;
div128_by_32(USER_HZ, 0, tb_ticks_per_sec, &res);
@@ -441,7 +431,7 @@ EXPORT_SYMBOL(profile_pc);
/*
* This function recalibrates the timebase based on the 49-bit time-of-day
* value in the Titan chip. The Titan is much more accurate than the value
- * returned by the service processor for the timebase frequency.
+ * returned by the service processor for the timebase frequency.
*/
static int __init iSeries_tb_recal(void)
@@ -576,9 +566,8 @@ void arch_irq_work_raise(void)
void timer_interrupt(struct pt_regs * regs)
{
struct pt_regs *old_regs;
- struct decrementer_clock *decrementer = &__get_cpu_var(decrementers);
- struct clock_event_device *evt = &decrementer->event;
- u64 now;
+ u64 *next_tb = &__get_cpu_var(decrementers_next_tb);
+ struct clock_event_device *evt = &__get_cpu_var(decrementers);
/* Ensure a positive value is written to the decrementer, or else
* some CPUs will continue to take decrementer exceptions.
@@ -613,16 +602,9 @@ void timer_interrupt(struct pt_regs * regs)
get_lppaca()->int_dword.fields.decr_int = 0;
#endif
- now = get_tb_or_rtc();
- if (now >= decrementer->next_tb) {
- decrementer->next_tb = ~(u64)0;
- if (evt->event_handler)
- evt->event_handler(evt);
- } else {
- now = decrementer->next_tb - now;
- if (now <= DECREMENTER_MAX)
- set_dec((int)now);
- }
+ *next_tb = ~(u64)0;
+ if (evt->event_handler)
+ evt->event_handler(evt);
#ifdef CONFIG_PPC_ISERIES
if (firmware_has_feature(FW_FEATURE_ISERIES) && hvlpevent_is_pending())
@@ -650,9 +632,9 @@ static void generic_suspend_disable_irqs(void)
* with suspending.
*/
- set_dec(0x7fffffff);
+ set_dec(DECREMENTER_MAX);
local_irq_disable();
- set_dec(0x7fffffff);
+ set_dec(DECREMENTER_MAX);
}
static void generic_suspend_enable_irqs(void)
@@ -824,9 +806,8 @@ void update_vsyscall(struct timespec *wall_time, struct timespec *wtm,
++vdso_data->tb_update_count;
smp_mb();
- /* XXX this assumes clock->shift == 22 */
- /* 4611686018 ~= 2^(20+64-22) / 1e9 */
- new_tb_to_xs = (u64) mult * 4611686018ULL;
+ /* 19342813113834067 ~= 2^(20+64) / 1e9 */
+ new_tb_to_xs = (u64) mult * (19342813113834067ULL >> clock->shift);
new_stamp_xsec = (u64) wall_time->tv_nsec * XSEC_PER_SEC;
do_div(new_stamp_xsec, 1000000000);
new_stamp_xsec += (u64) wall_time->tv_sec * XSEC_PER_SEC;
@@ -877,9 +858,7 @@ static void __init clocksource_init(void)
else
clock = &clocksource_timebase;
- clock->mult = clocksource_hz2mult(tb_ticks_per_sec, clock->shift);
-
- if (clocksource_register(clock)) {
+ if (clocksource_register_hz(clock, tb_ticks_per_sec)) {
printk(KERN_ERR "clocksource: %s is already registered\n",
clock->name);
return;
@@ -892,7 +871,7 @@ static void __init clocksource_init(void)
static int decrementer_set_next_event(unsigned long evt,
struct clock_event_device *dev)
{
- __get_cpu_var(decrementers).next_tb = get_tb_or_rtc() + evt;
+ __get_cpu_var(decrementers_next_tb) = get_tb_or_rtc() + evt;
set_dec(evt);
return 0;
}
@@ -904,34 +883,9 @@ static void decrementer_set_mode(enum clock_event_mode mode,
decrementer_set_next_event(DECREMENTER_MAX, dev);
}
-static inline uint64_t div_sc64(unsigned long ticks, unsigned long nsec,
- int shift)
-{
- uint64_t tmp = ((uint64_t)ticks) << shift;
-
- do_div(tmp, nsec);
- return tmp;
-}
-
-static void __init setup_clockevent_multiplier(unsigned long hz)
-{
- u64 mult, shift = 32;
-
- while (1) {
- mult = div_sc64(hz, NSEC_PER_SEC, shift);
- if (mult && (mult >> 32UL) == 0UL)
- break;
-
- shift--;
- }
-
- decrementer_clockevent.shift = shift;
- decrementer_clockevent.mult = mult;
-}
-
static void register_decrementer_clockevent(int cpu)
{
- struct clock_event_device *dec = &per_cpu(decrementers, cpu).event;
+ struct clock_event_device *dec = &per_cpu(decrementers, cpu);
*dec = decrementer_clockevent;
dec->cpumask = cpumask_of(cpu);
@@ -946,7 +900,8 @@ static void __init init_decrementer_clockevent(void)
{
int cpu = smp_processor_id();
- setup_clockevent_multiplier(ppc_tb_freq);
+ clockevents_calc_mult_shift(&decrementer_clockevent, ppc_tb_freq, 4);
+
decrementer_clockevent.max_delta_ns =
clockevent_delta2ns(DECREMENTER_MAX, &decrementer_clockevent);
decrementer_clockevent.min_delta_ns =
@@ -1014,10 +969,10 @@ void __init time_init(void)
boot_tb = get_tb_or_rtc();
/* If platform provided a timezone (pmac), we correct the time */
- if (timezone_offset) {
+ if (timezone_offset) {
sys_tz.tz_minuteswest = -timezone_offset / 60;
sys_tz.tz_dsttime = 0;
- }
+ }
vdso_data->tb_update_count = 0;
vdso_data->tb_ticks_per_sec = tb_ticks_per_sec;
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