[PATCHv2 05/11] arm: arch_timer: split cntfrq accessor

Mark Rutland mark.rutland at arm.com
Wed Dec 19 10:11:04 EST 2012


The CNTFRQ register is not duplicated for physical and virtual timers,
and accessing it as if it were is confusing.

Instead, use a separate accessor which doesn't take the access type
as a parameter.

Signed-off-by: Mark Rutland <mark.rutland at arm.com>
Acked-by: Catalin Marinas <catalin.marinas at arm.com>
Acked-by: Marc Zyngier <marc.zyngier at arm.com>
---
 arch/arm/kernel/arch_timer.c |   17 +++++++++--------
 1 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/arch/arm/kernel/arch_timer.c b/arch/arm/kernel/arch_timer.c
index 0d2681c..fc87d3d 100644
--- a/arch/arm/kernel/arch_timer.c
+++ b/arch/arm/kernel/arch_timer.c
@@ -51,8 +51,7 @@ static bool arch_timer_use_virtual = true;
 #define ARCH_TIMER_CTRL_IT_STAT		(1 << 2)
 
 #define ARCH_TIMER_REG_CTRL		0
-#define ARCH_TIMER_REG_FREQ		1
-#define ARCH_TIMER_REG_TVAL		2
+#define ARCH_TIMER_REG_TVAL		1
 
 #define ARCH_TIMER_PHYS_ACCESS		0
 #define ARCH_TIMER_VIRT_ACCESS		1
@@ -101,9 +100,6 @@ static inline u32 arch_timer_reg_read(const int access, const int reg)
 		case ARCH_TIMER_REG_TVAL:
 			asm volatile("mrc p15, 0, %0, c14, c2, 0" : "=r" (val));
 			break;
-		case ARCH_TIMER_REG_FREQ:
-			asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (val));
-			break;
 		}
 	}
 
@@ -121,6 +117,13 @@ static inline u32 arch_timer_reg_read(const int access, const int reg)
 	return val;
 }
 
+static inline u32 arch_timer_get_cntfrq(void)
+{
+	u32 val;
+	asm volatile("mrc p15, 0, %0, c14, c0, 0" : "=r" (val));
+	return val;
+}
+
 static inline u64 arch_counter_get_cntpct(void)
 {
 	u64 cval;
@@ -253,9 +256,7 @@ static int arch_timer_available(void)
 	u32 freq;
 
 	if (arch_timer_rate == 0) {
-		freq = arch_timer_reg_read(ARCH_TIMER_PHYS_ACCESS,
-					   ARCH_TIMER_REG_FREQ);
-
+		freq = arch_timer_get_cntfrq();
 		/* Check the timer frequency. */
 		if (freq == 0) {
 			pr_warn("Architected timer frequency not available\n");
-- 
1.7.0.4





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