[PATCHv4] arm: l2x0: add PMU support

[Kim Phillips]

On Thu, 1 Sep 2016 16:37:07 +0100
Russell King - ARM Linux <linux at armlinux.org.uk> wrote:

> On Wed, Aug 31, 2016 at 03:23:36PM +0100, Mark Rutland wrote:
> > The L2C-220 (AKA L220) and L2C-310 (AKA PL310) cache controllers feature
> > a Performance Monitoring Unit (PMU), which can be useful for tuning
> > and/or debugging. This hardware is always present and the relevant
> > registers are accessible to non-secure accesses. Thus, no special
> > firmware interface is necessary.
> > 
> > This patch adds support for the PMU, plugging into the usual perf
> > infrastructure. The overflow interrupt is not always available (e.g. on
> > RealView PBX A9 it is not wired up at all), and the hardware counters
> > saturate, so the driver does not make use of this. Instead, the driver
> > periodically polls and reset counters as required to avoid losing
> > events due to saturation.
> > 
> > Signed-off-by: Mark Rutland <mark.rutland at arm.com>
> > Acked-by: Pawel Moll <pawel.moll at arm.com>
> > Cc: Kim Phillips <kim.phillips at arm.com>
> > Cc: Russell King <linux at armlinux.org.uk>
> > Cc: Will Deacon <will.deacon at arm.com>
> 
> Much better, thanks.  When you're happy, please put it in the patch
> system, thanks.

feel free to tack on my:

Tested-by: Kim Phillips <kim.phillips at arm.com>

Thanks,

Kim