Re: [PATCH 2/2] cpufreq: amd-pstate: Use amd_get_highest_perf() to lookup perf values

[Mario Limonciello]

On 6/26/2024 12:18, Borislav Petkov wrote:
> On Tue, Jun 25, 2024 at 11:20:43PM -0500, Mario Limonciello wrote:
> > +	/*
> > +	 * For AMD CPUs with Family ID 19H and Model ID range 0x70 to 0x7f,
> > +	 * the highest performance level is set to 196.
> > +	 * https://bugzilla.kernel.org/show_bug.cgi?id=218759
> > +	 */
> > +	if (cpu_feature_enabled(X86_FEATURE_ZEN4)) {
> > +		switch (c->x86_model) {
> > +		case 0x70 ... 0x7f:
>
> Aha, so here it is non-inclusive - "<" and not "<=".
>
> So you need to check the model ranges first.
>
> > +			return CPPC_HIGHEST_PERF_PERFORMANCE;
> > +		default:
> > +			return CPPC_HIGHEST_PERF_DEFAULT;
>
> As for patch 1.
>
> > +		}
> > +	}
> > +
> > +	return CPPC_HIGHEST_PERF_DEFAULT;
> >   }
> >   EXPORT_SYMBOL_GPL(amd_get_highest_perf);
> >   
> > diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> > index 80eaa58f1405..f468d8562e17 100644
> > --- a/drivers/cpufreq/amd-pstate.c
> > +++ b/drivers/cpufreq/amd-pstate.c
> > @@ -52,8 +52,6 @@
> >   #define AMD_PSTATE_TRANSITION_LATENCY	20000
> >   #define AMD_PSTATE_TRANSITION_DELAY	1000
> >   #define AMD_PSTATE_FAST_CPPC_TRANSITION_DELAY 600
> > -#define CPPC_HIGHEST_PERF_PERFORMANCE	196
> > -#define CPPC_HIGHEST_PERF_DEFAULT	166
> >   
> >   #define AMD_CPPC_EPP_PERFORMANCE		0x00
> >   #define AMD_CPPC_EPP_BALANCE_PERFORMANCE	0x80
>
> This already doesn't apply:
>
> checking file arch/x86/kernel/cpu/amd.c
> checking file drivers/cpufreq/amd-pstate.c
> Hunk #1 FAILED at 52.

I was thinking we would take this patch through superm1/linux-next or 
linux-pm/linux-next as there is other amd-pstate stuff for the next 
merge window, but if you'd rather go through x86 then we can wait until 
after the merge window on this series.