[PATCH 3/4] mach-integrator: modernize clock event registration

Thomas Gleixner tglx at linutronix.de
Thu Sep 8 05:33:48 EDT 2011


On Thu, 8 Sep 2011, Russell King - ARM Linux wrote:

> On Wed, Sep 07, 2011 at 12:02:52PM +0200, Thomas Gleixner wrote:
> > On Wed, 7 Sep 2011, Linus Walleij wrote:
> > 
> > > From: Linus Walleij <linus.walleij at linaro.org>
> > > 
> > > Drop the reload value for the timer - the timekeeping code
> > > will call the .set_next_event to set this anyway.
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> 
> > > 
> > > Drop mult, shift and delta calculations and let the
> > > clockevent core scale this as appropriate.
> > > 
> > > Set the minimum interval to 1 rather than 15 (0xf), there
> > > is nothing in the data sheets I have indicating that 15
> > > should be some minimum value.
> > > 
> > > Cc: Russell King <linux at arm.linux.org.uk>
> > 
> > Acked-by: Thomas Gleixner <tglx at linutronix.de>
> 
> I mentioned to Thomas that which I've underlined above yesterday after I
> received Thomas' ack.  I was expecting Thomas to reply about this, but
> that obviously hasn't happened, so now that it's appeared in the patch
> system, it's become my problem to deal with.

Sorry, I missed that detail in the patch :(
 
> My understanding is that periodic timers are not setup by the generic
> clock event code, and so we do need to keep the 'timer_reload' stuff
> around.  Note that patch 2 deletes the register write for this too,
> so you actually have one logical change split across patch 2 and 3.

Periodic mode is set up via clkevt->set_mode() if the clock event
device provides CLOCK_EVT_FEAT_PERIODIC.

clkevt->set_next_event() is only used in oneshot mode.

Thanks,

	tglx



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