[PATCHv2 04/11] arm: arch_timer: standardise counter reading

Mark Rutland mark.rutland at arm.com
Wed Dec 19 10:11:03 EST 2012


We're currently inconsistent with respect to our accesses to the
physical and virtual counters, mixing and matching the two.

This patch introduces and uses a function for accessing the correct
counter based on whether we're using physical or virtual interrupts.
All current accesses to the counter accessors are redirected through
it.

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 |   48 ++++++++++-------------------------------
 1 files changed, 12 insertions(+), 36 deletions(-)

diff --git a/arch/arm/kernel/arch_timer.c b/arch/arm/kernel/arch_timer.c
index 498c29f..0d2681c 100644
--- a/arch/arm/kernel/arch_timer.c
+++ b/arch/arm/kernel/arch_timer.c
@@ -272,51 +272,32 @@ static int arch_timer_available(void)
 	return 0;
 }
 
-static u32 notrace arch_counter_get_cntpct32(void)
+u64 arch_timer_read_counter(void)
 {
-	cycle_t cnt = arch_counter_get_cntpct();
-
-	/*
-	 * The sched_clock infrastructure only knows about counters
-	 * with at most 32bits. Forget about the upper 24 bits for the
-	 * time being...
-	 */
-	return (u32)cnt;
+	if (arch_timer_use_virtual)
+		return arch_counter_get_cntvct();
+	else
+		return arch_counter_get_cntpct();
 }
 
-static u32 notrace arch_counter_get_cntvct32(void)
+static u32 arch_timer_read_counter32(void)
 {
-	cycle_t cnt = arch_counter_get_cntvct();
-
-	/*
-	 * The sched_clock infrastructure only knows about counters
-	 * with at most 32bits. Forget about the upper 24 bits for the
-	 * time being...
-	 */
-	return (u32)cnt;
+	return arch_timer_read_counter();
 }
 
 static cycle_t arch_counter_read(struct clocksource *cs)
 {
-	/*
-	 * Always use the physical counter for the clocksource.
-	 * CNTHCTL.PL1PCTEN must be set to 1.
-	 */
-	return arch_counter_get_cntpct();
+	return arch_timer_read_counter();
 }
 
 static unsigned long arch_timer_read_current_timer(void)
 {
-	return arch_counter_get_cntpct();
+	return arch_timer_read_counter();
 }
 
 static cycle_t arch_counter_read_cc(const struct cyclecounter *cc)
 {
-	/*
-	 * Always use the physical counter for the clocksource.
-	 * CNTHCTL.PL1PCTEN must be set to 1.
-	 */
-	return arch_counter_get_cntpct();
+	return arch_timer_read_counter();
 }
 
 static struct clocksource clocksource_counter = {
@@ -489,18 +470,13 @@ int __init arch_timer_of_register(void)
 
 int __init arch_timer_sched_clock_init(void)
 {
-	u32 (*cnt32)(void);
 	int err;
 
 	err = arch_timer_available();
 	if (err)
 		return err;
 
-	if (arch_timer_use_virtual)
-		cnt32 = arch_counter_get_cntvct32;
-	else
-		cnt32 = arch_counter_get_cntpct32;
-
-	setup_sched_clock(cnt32, 32, arch_timer_rate);
+	setup_sched_clock(arch_timer_read_counter32,
+			  32, arch_timer_rate);
 	return 0;
 }
-- 
1.7.0.4





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