watchdog: sp805: replace readl/writel with lighter _relaxed variants
authorViresh Kumar <viresh.kumar@st.com>
Mon, 12 Mar 2012 04:22:14 +0000 (09:52 +0530)
committerWim Van Sebroeck <wim@iguana.be>
Tue, 27 Mar 2012 18:14:31 +0000 (20:14 +0200)
readl/writel versions for ARM contain memory barrier instruction for
synchronizing DMA buffers.  These are not required at least on this
module.  So use lighter _relaxed variants.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
drivers/watchdog/sp805_wdt.c

index 3e4edda261d1da4ae536167a827a55c0cff7864b..6e751573a2d12170f427ad04c24eba1ff36990d7 100644 (file)
@@ -113,10 +113,10 @@ static u32 wdt_timeleft(void)
        rate = clk_get_rate(wdt->clk);
 
        spin_lock(&wdt->lock);
-       load = readl(wdt->base + WDTVALUE);
+       load = readl_relaxed(wdt->base + WDTVALUE);
 
        /*If the interrupt is inactive then time left is WDTValue + WDTLoad. */
-       if (!(readl(wdt->base + WDTRIS) & INT_MASK))
+       if (!(readl_relaxed(wdt->base + WDTRIS) & INT_MASK))
                load += wdt->load_val + 1;
        spin_unlock(&wdt->lock);
 
@@ -128,14 +128,14 @@ static void wdt_enable(void)
 {
        spin_lock(&wdt->lock);
 
-       writel(UNLOCK, wdt->base + WDTLOCK);
-       writel(wdt->load_val, wdt->base + WDTLOAD);
-       writel(INT_MASK, wdt->base + WDTINTCLR);
-       writel(INT_ENABLE | RESET_ENABLE, wdt->base + WDTCONTROL);
-       writel(LOCK, wdt->base + WDTLOCK);
+       writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
+       writel_relaxed(wdt->load_val, wdt->base + WDTLOAD);
+       writel_relaxed(INT_MASK, wdt->base + WDTINTCLR);
+       writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base + WDTCONTROL);
+       writel_relaxed(LOCK, wdt->base + WDTLOCK);
 
        /* Flush posted writes. */
-       readl(wdt->base + WDTLOCK);
+       readl_relaxed(wdt->base + WDTLOCK);
        spin_unlock(&wdt->lock);
 }
 
@@ -144,12 +144,12 @@ static void wdt_disable(void)
 {
        spin_lock(&wdt->lock);
 
-       writel(UNLOCK, wdt->base + WDTLOCK);
-       writel(0, wdt->base + WDTCONTROL);
-       writel(LOCK, wdt->base + WDTLOCK);
+       writel_relaxed(UNLOCK, wdt->base + WDTLOCK);
+       writel_relaxed(0, wdt->base + WDTCONTROL);
+       writel_relaxed(LOCK, wdt->base + WDTLOCK);
 
        /* Flush posted writes. */
-       readl(wdt->base + WDTLOCK);
+       readl_relaxed(wdt->base + WDTLOCK);
        spin_unlock(&wdt->lock);
 }