clocksource: dbx500-prcmu: use relaxed readl variant

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@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Fabio Baltieri <fabio.baltieri@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/clocksource/clksrc-dbx500-prcmu.c b/drivers/clocksource/clksrc-dbx500-prcmu.c
index 54f3d11..138c5a5 100644 (file)
--- a/drivers/clocksource/clksrc-dbx500-prcmu.c
+++ b/drivers/clocksource/clksrc-dbx500-prcmu.c
@@ -30,15 +30,14 @@
 
 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 */