[PATCH v4 4/5] arm64/perf: Enable PMCR long cycle counter bit

Will Deacon will.deacon at arm.com
Mon Feb 22 05:41:05 PST 2016


On Mon, Feb 22, 2016 at 01:45:14PM +0100, Jan Glauber wrote:
> On Thu, Feb 18, 2016 at 05:34:28PM +0000, Will Deacon wrote:
> > On Thu, Feb 18, 2016 at 05:50:13PM +0100, Jan Glauber wrote:
> > > With the long cycle counter bit (LC) disabled the cycle counter is not
> > > working on ThunderX SOC (ThunderX only implements Aarch64).
> > > Also, according to documentation LC == 0 is deprecated.
> > > 
> > > To keep the code simple the patch does not introduce 64 bit wide counter
> > > functions. Instead writing the cycle counter always sets the upper
> > > 32 bits so overflow interrupts are generated as before.
> > > 
> > > Original patch from Andrew Pinksi <Andrew.Pinksi at caviumnetworks.com>
> > 
> > What does this mean? Do we need Andrew's S-o-B, or is this a fresh patch?
> 
> Please let me know if I should repost or not, FWIW I got Andrew's S-o-B on the
> patch.

I think it's fine. This should all be in -next as of last Friday anyhow.

Will



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