[PATCH 1/2] clocksource: dbx500-prcmu: use relaxed readl variant
Fabio Baltieri
fabio.baltieri at linaro.org
Mon Jan 21 07:09:31 EST 2013
From: Rabin Vincent <rabin.vincent at stericsson.com>
Modify clksrc_dbx500_prcmu_read to replace readl() with readl_relaxed().
This speeds up calls to the function by about 40%.
Signed-off-by: Rabin Vincent <rabin.vincent at stericsson.com>
Acked-by: Linus Walleij <linus.walleij at linaro.org>
Signed-off-by: Fabio Baltieri <fabio.baltieri at linaro.org>
---
drivers/clocksource/clksrc-dbx500-prcmu.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/drivers/clocksource/clksrc-dbx500-prcmu.c b/drivers/clocksource/clksrc-dbx500-prcmu.c
index c26c369..159f54a 100644
--- a/drivers/clocksource/clksrc-dbx500-prcmu.c
+++ b/drivers/clocksource/clksrc-dbx500-prcmu.c
@@ -33,15 +33,14 @@
static void __iomem *clksrc_dbx500_timer_base;
-static cycle_t clksrc_dbx500_prcmu_read(struct clocksource *cs)
+static cycle_t notrace clksrc_dbx500_prcmu_read(struct clocksource *cs)
{
+ void __iomem *base = clksrc_dbx500_timer_base;
u32 count, count2;
do {
- count = readl(clksrc_dbx500_timer_base +
- PRCMU_TIMER_DOWNCOUNT);
- count2 = readl(clksrc_dbx500_timer_base +
- PRCMU_TIMER_DOWNCOUNT);
+ count = readl_relaxed(base + PRCMU_TIMER_DOWNCOUNT);
+ count2 = readl_relaxed(base + PRCMU_TIMER_DOWNCOUNT);
} while (count2 != count);
/* Negate because the timer is a decrementing counter */
--
1.7.12.1
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