From mboxrd@z Thu Jan  1 00:00:00 1970
From: tglx@linutronix.de (Thomas Gleixner)
Date: Wed, 1 Jul 2015 15:28:08 +0200 (CEST)
Subject: [PATCH v2 4/9] arm: twr-k70f120m: timer driver for Kinetis SoC
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 <alpine.DEB.2.11.1507010944580.3916@nanos>
 <alpine.LNX.2.00.1507011031050.9009@localhost.localdomain>
Message-ID: <alpine.DEB.2.11.1507011527380.3916@nanos>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Wed, 1 Jul 2015, Paul Osmialowski wrote:

> Hi Thomas,
> 
> On Wed, 1 Jul 2015, Thomas Gleixner wrote:
> 
> > > +		clockevents_register_device(
> > > +				&kinetis_clockevent_tmrs[chan].evtdev);
> > > +
> > > +		kinetis_pit_init(&kinetis_clockevent_tmrs[chan],
> > > +						(rate / HZ) - 1);
> > > +		kinetis_pit_enable(&kinetis_clockevent_tmrs[chan], 1);
> > 
> > No point doing this. The core code has invoked the set_periodic call
> > back via clockevents_register_device() already.
> > 
> 
> 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().

Thanks,

	tglx