linux-kernel - RE: [PATCH 4/4] cpufreq/amd-pstate: Drop needless EPP initialization

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Message-ID:
 <CYYPR12MB865502F3583B68501F87C0B29C462@CYYPR12MB8655.namprd12.prod.outlook.com>
Date: Wed, 16 Oct 2024 04:33:25 +0000
From: "Yuan, Perry" <Perry.Yuan@....com>
To: "Limonciello, Mario" <Mario.Limonciello@....com>, "Shenoy, Gautham Ranjal"
	<gautham.shenoy@....com>
CC: "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-pm@...r.kernel.org" <linux-pm@...r.kernel.org>, "Ugwekar, Dhananjay"
	<Dhananjay.Ugwekar@....com>
Subject: RE: [PATCH 4/4] cpufreq/amd-pstate: Drop needless EPP initialization

[Public]

> -----Original Message-----
> From: Limonciello, Mario <Mario.Limonciello@....com>
> Sent: Sunday, October 13, 2024 1:45 AM
> To: Shenoy, Gautham Ranjal <gautham.shenoy@....com>
> Cc: Yuan, Perry <Perry.Yuan@....com>; linux-kernel@...r.kernel.org; linux-
> pm@...r.kernel.org; Ugwekar, Dhananjay <Dhananjay.Ugwekar@....com>;
> Limonciello, Mario <Mario.Limonciello@....com>
> Subject: [PATCH 4/4] cpufreq/amd-pstate: Drop needless EPP initialization
>
> The EPP value doesn't need to be cached to the CPPC request in
> amd_pstate_epp_update_limit() because it's passed as an argument at the end to
> amd_pstate_set_epp() and stored at that time.
>
> Signed-off-by: Mario Limonciello <mario.limonciello@....com>
> ---
>  drivers/cpufreq/amd-pstate.c | 6 ------
>  1 file changed, 6 deletions(-)
>
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index
> 8d2541f2c74b..90868c8b214e 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -1528,12 +1528,6 @@ static int amd_pstate_epp_update_limit(struct
> cpufreq_policy *policy)
>       if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE)
>               epp = 0;
>
> -     /* Set initial EPP value */
> -     if (cpu_feature_enabled(X86_FEATURE_CPPC)) {
> -             value &= ~GENMASK_ULL(31, 24);
> -             value |= (u64)epp << 24;
> -     }
> -
>       WRITE_ONCE(cpudata->cppc_req_cached, value);
>       return amd_pstate_set_epp(cpudata, epp);  }
> --
> 2.43.0

LGTM, thanks.

Reviewed-by: Perry Yuan <perry.yuan@....com>