[PATCH 1/3] ARM: OMAP2+: 32k-counter: Use hwmod lookup to check presence of 32k timer

[Russell King - ARM Linux]

On Tue, Apr 10, 2012 at 02:27:36PM +0530, Santosh Shilimkar wrote:
> On Tuesday 10 April 2012 02:14 PM, Russell King - ARM Linux wrote:
> > On Mon, Apr 09, 2012 at 03:18:22PM -0500, Jon Hunter wrote:
> >> True, but we would always want to use the 32k timer if CONFIG_PM is  
> >> specified. So what I am saying is that if a device has a 32ksync timer  
> >> and CONFIG_PM is defined, we always want to use the 32ksync timer and a  
> >> gptimer should never be used.
> > 
> > Why?  What if you want to have PM enabled, and you also want to use the
> > kernels high resolution timers, or you want more accurate timing than
> > the 30.5us tick interval of the 32k timer?
> 
> You might have missed the earlier comments on the thread. High
> resolution GP timer(sysclk) will stop in deeper power states and
> hence it can't be used with PM enabled usecases.

Which means folk should be given the choice at boot time between running
with the deeper power states and having a higher resolution timing source,
rather than denying them the higher resolution timing source when PM is
enabled.