Re: [PATCH v2 4/9] arm: twr-k70f120m: timer driver for Kinetis SoC

Paul Osmialowski
2015-07-01T14:20:48Z

On Wed, 1 Jul 2015, Thomas Gleixner wrote:

>>
>> As I removed this kinetis_pit_enable() line, the timer did not start,
>> therefore the system became unusable. What could be possible reason for that?
>
> Well, you need to move both, the init and the enable into
> set_periodic().
>

Indeed, something like this worked:

diff --git a/drivers/clocksource/timer-kinetis.c
b/drivers/clocksource/timer-kinetis.c
index 1424308..41ef94f 100644
--- a/drivers/clocksource/timer-kinetis.c
+++ b/drivers/clocksource/timer-kinetis.c
@@ -61,6 +61,7 @@ struct kinetis_clock_event_ddata {
struct clock_event_device evtdev;
void __iomem *base;
void __iomem *mcr;
+ unsigned long rate;
spinlock_t lock;
};

@@ -115,6 +116,7 @@ static int kinetis_clockevent_tmr_set_state_periodic(
struct kinetis_clock_event_ddata *pit =
container_of(evt, struct kinetis_clock_event_ddata,
evtdev);

+ kinetis_pit_init(pit, (pit->rate / HZ) - 1);
kinetis_pit_enable(pit, 1);

return 0;
@@ -235,6 +237,7 @@ static void __init kinetis_clockevent_init(struct
device_node *np)
kinetis_clockevent_tmr_set_state_oneshot;
kinetis_tmr->base = base;
kinetis_tmr->mcr = mcr;
+ kinetis_tmr->rate = rate;
spin_lock_init(&kinetis_tmr->lock);

/*
@@ -250,9 +253,6 @@ static void __init kinetis_clockevent_init(struct
device_node *np)

clockevents_register_device(&kinetis_tmr->evtdev);

- kinetis_pit_init(kinetis_tmr, (rate / HZ) - 1);
- kinetis_pit_enable(kinetis_tmr, 1);
-
if (request_irq(irq, kinetis_clockevent_tmr_irq_handler,
IRQF_TIMER | IRQF_IRQPOLL,
"kinetis-timer",