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Date: Thu, 11 Jan 2024 01:19:25 +0800
From: Huang Rui <ray.huang@amd.com>
To: "Rafael J. Wysocki" <rafael@kernel.org>,
	Erwan Velu <erwanaliasr1@gmail.com>
Cc: Erwan Velu <e.velu@criteo.com>, Viresh Kumar <viresh.kumar@linaro.org>,
	"linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 2/2] cpufreq/amd-pstate: Adding Zen4 support in
 introduction
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References: <20240109175844.448006-1-e.velu@criteo.com>
 <CAJZ5v0ipYQURmFGGwmS5oyOuAOFDbG7TaaaWg4Ze-7PpBnSwkQ@mail.gmail.com>
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On Wed, Jan 10, 2024 at 10:21:20PM +0800, Rafael J. Wysocki wrote:
> On Tue, Jan 9, 2024 at 6:58 PM Erwan Velu <erwanaliasr1@gmail.com> wrote:
> >
> > amd-pstate is implemented on Zen4, adding this architecture in the
> > introduction.
> >
> > Signed-off-by: Erwan Velu <e.velu@criteo.com>
> > ---
> >  drivers/cpufreq/amd-pstate.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> > index 1f6186475715..9a8d083f6ba5 100644
> > --- a/drivers/cpufreq/amd-pstate.c
> > +++ b/drivers/cpufreq/amd-pstate.c
> > @@ -14,7 +14,7 @@
> >   * communicate the performance hints to hardware.
> >   *
> >   * AMD P-State is supported on recent AMD Zen base CPU series include some of
> > - * Zen2 and Zen3 processors. _CPC needs to be present in the ACPI tables of AMD
> > + * Zen2, Zen3 and Zen4 processors. _CPC needs to be present in the ACPI tables of AMD
> 
> IMO, it would be really nice to avoid extending this line so much, but
> this is up to the AMD people.

Agree. Actually, we will use this driver for all future AMD CPU generations
that starts from paritial Zen2.

> 
> Also, while you are at it, "include" in the first sentence should be
> "including" and a new paragraph after "processors." would make this
> comment easier to follow from the logical standpoint, because the
> first sentence is about the supported platforms and the second one is
> about additional requirements (ie. something else).
> 

How about modifying here as "partial Zen2, Zen3, and future processors"?

Thanks,
Ray

> >   * P-State supported system. And there are two types of hardware implementations
> >   * for AMD P-State: 1) Full MSR Solution and 2) Shared Memory Solution.
> >   * X86_FEATURE_CPPC CPU feature flag is used to distinguish the different types.
> > --