From: Michal Simek <monstr@monstr.eu>
Date: Thu, 10 Jun 2010 14:04:05 +0000 (+0200)
Subject: microblaze: Decrease time shifting values
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=c8f77436d11190d0d9379f4fb2c6f22a155c8d8e;p=linux-beck.git

microblaze: Decrease time shifting values

Lower shifting values ensure that shifted 32bit counter
value doesn't exceed 64bit cycle variable too fast.

Signed-off-by: Michal Simek <monstr@monstr.eu>
---

diff --git a/arch/microblaze/kernel/timer.c b/arch/microblaze/kernel/timer.c
index 22e296eb871b..b1380ae93ae1 100644
--- a/arch/microblaze/kernel/timer.c
+++ b/arch/microblaze/kernel/timer.c
@@ -28,6 +28,7 @@
 #include <asm/prom.h>
 #include <asm/irq.h>
 #include <asm/system.h>
+#include <linux/cnt32_to_63.h>
 
 #ifdef CONFIG_SELFMOD_TIMER
 #include <asm/selfmod.h>
@@ -135,7 +136,7 @@ static void microblaze_timer_set_mode(enum clock_event_mode mode,
 static struct clock_event_device clockevent_microblaze_timer = {
 	.name		= "microblaze_clockevent",
 	.features       = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC,
-	.shift		= 24,
+	.shift		= 8,
 	.rating		= 300,
 	.set_next_event	= microblaze_timer_set_next_event,
 	.set_mode	= microblaze_timer_set_mode,
@@ -195,7 +196,7 @@ static cycle_t microblaze_cc_read(const struct cyclecounter *cc)
 static struct cyclecounter microblaze_cc = {
 	.read = microblaze_cc_read,
 	.mask = CLOCKSOURCE_MASK(32),
-	.shift = 24,
+	.shift = 8,
 };
 
 int __init init_microblaze_timecounter(void)
@@ -213,7 +214,7 @@ static struct clocksource clocksource_microblaze = {
 	.rating		= 300,
 	.read		= microblaze_read,
 	.mask		= CLOCKSOURCE_MASK(32),
-	.shift		= 24, /* I can shift it */
+	.shift		= 8, /* I can shift it */
 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
 };
 
@@ -302,7 +303,7 @@ unsigned long long notrace sched_clock(void)
 {
 	if (timer_initialized) {
 		struct clocksource *cs = &clocksource_microblaze;
-		cycle_t cyc = cs->read(NULL);
+		cycle_t cyc = cnt32_to_63(cs->read(NULL));
 		return clocksource_cyc2ns(cyc, cs->mult, cs->shift);
 	}
 	return 0;