[PATCH 4/4][V2] ARM: timer-sp: Set dynamic irq affinity

Daniel Lezcano daniel.lezcano at linaro.org
Sat Mar 2 05:10:13 EST 2013

From: Viresh Kumar <viresh.kumar at linaro.org>

When a cpu goes to a deep idle state where its local timer is shutdown, it
notifies the time frame work to use the broadcast timer instead.

Unfortunately, the broadcast device could wake up any CPU, including an idle one
which is not concerned by the wake up at all.

This implies, in the worst case, an idle CPU will wake up to send an IPI to
another idle cpu.

This patch fixes this for ARM platforms using timer-sp, by setting

Signed-off-by: Viresh Kumar <viresh.kumar at linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano at linaro.org>
 arch/arm/common/timer-sp.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm/common/timer-sp.c b/arch/arm/common/timer-sp.c
index 9d2d3ba..ae3c0f9 100644
--- a/arch/arm/common/timer-sp.c
+++ b/arch/arm/common/timer-sp.c
@@ -158,7 +158,8 @@ static int sp804_set_next_event(unsigned long next,
 static struct clock_event_device sp804_clockevent = {
 	.set_mode	= sp804_set_mode,
 	.set_next_event	= sp804_set_next_event,
 	.rating		= 300,

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