[v10,11/11] OMAP: dmtimer: add timeout to low-level routines

Commit Message

Tarun Kanti DebBarma Feb. 16, 2011, 1 p.m. UTC

None

Patch

diff --git a/arch/arm/plat-omap/dmtimer.c b/arch/arm/plat-omap/dmtimer.c
index fcac422..a39d5ba 100644
--- a/arch/arm/plat-omap/dmtimer.c
+++ b/arch/arm/plat-omap/dmtimer.c
@@ -43,6 +43,7 @@ 
 #include <linux/err.h>
 #include <linux/platform_device.h>
 #include <plat/dmtimer.h>
+#include <plat/common.h>
 
 /* register offsets */
 #define _OMAP_TIMER_ID_OFFSET		0x00
@@ -153,6 +154,8 @@ 
 #define OMAP_TIMER_TICK_INT_MASK_COUNT_REG				\
 		(_OMAP_TIMER_TICK_INT_MASK_COUNT_OFFSET | (WP_TOWR << WPSHIFT))
 
+#define MAX_WRITE_PEND_WAIT		10000 /* 10ms timeout delay */
+
 static LIST_HEAD(omap_timer_list);
 static DEFINE_SPINLOCK(dm_timer_lock);
 
@@ -168,16 +171,23 @@  static DEFINE_SPINLOCK(dm_timer_lock);
 static inline u32 omap_dm_timer_read_reg(struct omap_dm_timer *timer, u32 reg)
 {
 	struct dmtimer_platform_data *pdata = timer->pdev->dev.platform_data;
+	int i = 0;
 
 	if (reg >= OMAP_TIMER_WAKEUP_EN_REG)
 		reg += pdata->func_offset;
 	else if (reg >= OMAP_TIMER_STAT_REG)
 		reg += pdata->intr_offset;
 
-	if (timer->posted)
-		while (readl(timer->io_base + (OMAP_TIMER_WRITE_PEND_REG & 0xff))
-				& (reg >> WPSHIFT))
-			cpu_relax();
+	if (timer->posted) {
+		omap_test_timeout(!(readl(timer->io_base +
+			((OMAP_TIMER_WRITE_PEND_REG +
+			pdata->func_offset) & 0xff)) & (reg >> WPSHIFT)),
+			MAX_WRITE_PEND_WAIT, i);
+
+		if (WARN_ON_ONCE(i == MAX_WRITE_PEND_WAIT))
+			pr_err(": read timeout\n");
+	}
+
 	return readl(timer->io_base + (reg & 0xff));
 }
 
@@ -195,16 +205,23 @@  static void omap_dm_timer_write_reg(struct omap_dm_timer *timer, u32 reg,
 						u32 value)
 {
 	struct dmtimer_platform_data *pdata = timer->pdev->dev.platform_data;
+	int i = 0;
 
 	if (reg >= OMAP_TIMER_WAKEUP_EN_REG)
 		reg += pdata->func_offset;
 	else if (reg >= OMAP_TIMER_STAT_REG)
 		reg += pdata->intr_offset;
 
-	if (timer->posted)
-		while (readl(timer->io_base + (OMAP_TIMER_WRITE_PEND_REG & 0xff))
-				& (reg >> WPSHIFT))
-			cpu_relax();
+	if (timer->posted) {
+		omap_test_timeout(!(readl(timer->io_base +
+			((OMAP_TIMER_WRITE_PEND_REG +
+			pdata->func_offset) & 0xff)) & (reg >> WPSHIFT)),
+			MAX_WRITE_PEND_WAIT, i);
+
+		if (WARN_ON(i == MAX_WRITE_PEND_WAIT))
+			pr_err(": write timeout\n");
+	}
+
 	writel(value, timer->io_base + (reg & 0xff));
 }