Re: [PATCH] arm: bump amount of PMU counters to pass SBSA ACS

[Leif Lindholm]

On Wed, Mar 03, 2021 at 18:06:46 +0000, Peter Maydell wrote:
> On Wed, 3 Mar 2021 at 17:48, Leif Lindholm <leif@nuviainc.com> wrote:
> > It would be good if we could get 6.0 closer to SBSA compliance.
> 
> How far away are we at the moment ?
> 
> > Would it be worth the effort to make this controllable per cpu model?
> 
> I don't have a strong opinion on whether we should, but if we do then the
> right way to implement that would be to have the PMCR reset value
> as a reset_pmcr_el0 field in struct ARMCPU (like the existing reset_fpsid,
> reset_sctlr, etc) that gets set per-CPU to whatever the CPU's value for
> it is; and then instead of using a PMCR_NUM_COUNTERS value,
> extract the PMCR.N field when needed. The hardest part would be
> going through all the CPU TRMs to find out the correct reset value.

That makes sense.

I guess we could also phase the transition by using the default value
if zero?

Regards,

Leif