Re: [PATCH] ARM: PMU: fix runtime PM enable

[Will Deacon <will.deacon@arm.com>]

On Thu, Oct 25, 2012 at 05:42:21PM +0100, Kevin Hilman wrote:
> Jon Hunter <jon-hunter@ti.com> writes:
> > On 10/24/2012 12:23 PM, Will Deacon wrote:
> >> What do other drivers do? Grepping around, I see calls to pm_runtime_enable
> >> made in various drivers and, given that you pass the device in there, what's
> >> the problem with us just calling that unconditionally from perf? I know you
> >> said that will work for OMAP, but I'm trying to understand the effect that
> >> has on PM-aware platforms that don't require this for the PMU (since this
> >> seems to be per-device).
> >
> > I had done this initially when testing on OMAP platforms that do and
> > don't require runtime PM for PMU. I don't see any side affect of this,
> > however, may be Kevin could comment on if that is ok. It would be the
> > best approach.
> 
> Unconditonally enabling runtime PM should be fine.  It may add a slight
> bit of overhead calling runtime PM functions that ultimately do nothing
> (because there are no callbacks), but it will be harmless.
> 
> Personally, I think that would be cleaner.  The less pdata we need, the
> better, IMO.

Thanks Kevin, I'm fine with that. Jon: want me to write a patch or do you
have something I can take into the ARM perf tree (if the latter, please
base against perf/updates)?

Cheers,

Will