X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=arch%2Fpowerpc%2Fkernel%2Ftime.c;h=2eaaa242c2e6a19b70ea24d46d4847703b71ffd1;hb=68568add2ca70153cca3dd1858eaa0776821cf75;hp=03b29a6759ab55b087528c9e1be70d095c2a8d2b;hpb=13c54137f7896928ced8e97708d409fa39c09e00;p=deliverable%2Flinux.git

diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 03b29a6759ab..2eaaa242c2e6 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,
 };
 
@@ -112,8 +108,6 @@ static void decrementer_set_mode(enum clock_event_mode mode,
 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,
@@ -578,7 +572,6 @@ 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;
 
 	/* Ensure a positive value is written to the decrementer, or else
 	 * some CPUs will continue to take decrementer exceptions.
@@ -613,16 +606,9 @@ 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);
-	}
+	decrementer->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())
@@ -824,9 +810,8 @@ 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 +862,7 @@ 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;
@@ -889,6 +872,15 @@ static void __init clocksource_init(void)
 	       clock->name, clock->mult, clock->shift);
 }
 
+void decrementer_check_overflow(void)
+{
+	u64 now = get_tb_or_rtc();
+	struct decrementer_clock *decrementer = &__get_cpu_var(decrementers);
+
+	if (now >= decrementer->next_tb)
+		set_dec(1);
+}
+
 static int decrementer_set_next_event(unsigned long evt,
 				      struct clock_event_device *dev)
 {
@@ -904,31 +896,6 @@ 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;
@@ -946,7 +913,8 @@ 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 =