From: Viresh Kumar viresh.kumar@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 CLOCK_EVT_FEAT_DYNIRQ feature.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org Signed-off-by: Daniel Lezcano daniel.lezcano@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 = { - .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, + .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT | + CLOCK_EVT_FEAT_DYNIRQ, .set_mode = sp804_set_mode, .set_next_event = sp804_set_next_event, .rating = 300,