[PATCH v2 2/2] ARM: delay: add registration mechanism for delay timer sources

Will Deacon will.deacon at arm.com
Fri Sep 7 13:07:32 EDT 2012

On Wed, Aug 29, 2012 at 10:25:24PM +0100, Will Deacon wrote:
> From: Jonathan Austin <Jonathan.Austin at arm.com>
> The current timer-based delay loop relies on the architected timer to
> initiate the switch away from the polling-based implementation. This is
> unfortunate for platforms without the architected timers but with a
> suitable delay source (that is, constant frequency, always powered-up
> and ticking as long as the CPUs are online).
> This patch introduces a registration mechanism for the delay timer
> (which provides an unconditional read_current_timer implementation) and
> updates the architected timer code to use the new interface.


> +int read_current_timer(unsigned long *timer_val)
> +{
> +	return delay_timer ? delay_timer->read_current_timer() : -ENXIO;
> +}

So this is clearly wrong with the new function prototype -- I've fixed it on
my delay branch (when the mirrors sync).


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