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

From: Yuan, Perry
Date: Wed Oct 16 2024 - 00:33:40 EST


[Public]

> -----Original Message-----
> From: Limonciello, Mario <Mario.Limonciello@xxxxxxx>
> Sent: Sunday, October 13, 2024 1:45 AM
> To: Shenoy, Gautham Ranjal <gautham.shenoy@xxxxxxx>
> Cc: Yuan, Perry <Perry.Yuan@xxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; linux-
> pm@xxxxxxxxxxxxxxx; Ugwekar, Dhananjay <Dhananjay.Ugwekar@xxxxxxx>;
> Limonciello, Mario <Mario.Limonciello@xxxxxxx>
> 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@xxxxxxx>
> ---
> 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@xxxxxxx>