[PATCH] clocksource/drivers/pistachio: Fix wrong calculated clocksource read value
Jisheng Zhang
jszhang at marvell.com
Wed Nov 25 07:42:49 PST 2015
Let's assume the counter value is 0xf000000, the pistachio clocksource
read cycles function would return 0xffffffff0fffffff, but it should
return 0xfffffff.
We fix this issue by calculating bitwise-not counter, then cast to
cycle_t.
Signed-off-by: Jisheng Zhang <jszhang at marvell.com>
---
drivers/clocksource/time-pistachio.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/clocksource/time-pistachio.c b/drivers/clocksource/time-pistachio.c
index bba6799..3269d9e 100644
--- a/drivers/clocksource/time-pistachio.c
+++ b/drivers/clocksource/time-pistachio.c
@@ -84,7 +84,7 @@ pistachio_clocksource_read_cycles(struct clocksource *cs)
counter = gpt_readl(pcs->base, TIMER_CURRENT_VALUE, 0);
raw_spin_unlock_irqrestore(&pcs->lock, flags);
- return ~(cycle_t)counter;
+ return (cycle_t)~counter;
}
static u64 notrace pistachio_read_sched_clock(void)
--
2.6.2
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