[PATCH 7/9] clocksource/drivers/imx: Allow timer irq affinity change

From: Daniel Lezcano
Date: Mon Oct 19 2015 - 17:01:10 EST


From: Lucas Stach <l.stach@xxxxxxxxxxxxxx>

Allow the timer core to change the smp affinity of the broadcast timer
irq by setting CLOCK_EVT_FEAT_DYNIRQ flag. For this to work the timer
core needs to be told about the used irq.

This reduces interrupt pressure and wakeups on CPU0 as well as vastly
reducing the number of timer broadcast IPIs.

Signed-off-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
---
drivers/clocksource/timer-imx-gpt.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/clocksource/timer-imx-gpt.c b/drivers/clocksource/timer-imx-gpt.c
index 839aba9..99ec967 100644
--- a/drivers/clocksource/timer-imx-gpt.c
+++ b/drivers/clocksource/timer-imx-gpt.c
@@ -305,13 +305,14 @@ static int __init mxc_clockevent_init(struct imx_timer *imxtm)
struct irqaction *act = &imxtm->act;

ced->name = "mxc_timer1";
- ced->features = CLOCK_EVT_FEAT_ONESHOT;
+ ced->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ;
ced->set_state_shutdown = mxc_shutdown;
ced->set_state_oneshot = mxc_set_oneshot;
ced->tick_resume = mxc_shutdown;
ced->set_next_event = imxtm->gpt->set_next_event;
ced->rating = 200;
ced->cpumask = cpumask_of(0);
+ ced->irq = imxtm->irq;
clockevents_config_and_register(ced, clk_get_rate(imxtm->clk_per),
0xff, 0xfffffffe);

--
1.9.1

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