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References: <20240119113319.54158-1-mario.limonciello@amd.com>
In-Reply-To: <20240119113319.54158-1-mario.limonciello@amd.com>
From: Wyes Karny <wkarny@gmail.com>
Date: Mon, 22 Jan 2024 20:27:07 +0530
Message-ID: <CAAE01kHEperoassBmLwM3pWhJmWpjRS2fcE8VPkLAgvz7yAuQA@mail.gmail.com>
Subject: Re: [PATCH] cpufreq/amd-pstate: Fix setting scaling max/min freq values
To: Mario Limonciello <mario.limonciello@amd.com>
Cc: ray.huang@amd.com, rafael@kernel.org, viresh.kumar@linaro.org, 
	linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, 
	stable@vger.kernel.org
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On Sat, Jan 20, 2024 at 5:49=E2=80=AFAM Mario Limonciello
<mario.limonciello@amd.com> wrote:
>
> Scaling min/max freq values were being cached and lagging a setting
> each time.  Fix the ordering of the clamp call to ensure they work.
>
> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=3D217931
> Cc: stable@vger.kernel.org
> Cc: wkarny@gmail.com
> Fixes: febab20caeba ("cpufreq/amd-pstate: Fix scaling_min_freq and scalin=
g_max_freq update")
> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>

Reviewed-by: Wyes Karny <wkarny@gmail.com>

> ---
>  drivers/cpufreq/amd-pstate.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index 1f6186475715..1791d37fbc53 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -1232,14 +1232,13 @@ static void amd_pstate_epp_update_limit(struct cp=
ufreq_policy *policy)
>         max_limit_perf =3D div_u64(policy->max * cpudata->highest_perf, c=
pudata->max_freq);
>         min_limit_perf =3D div_u64(policy->min * cpudata->highest_perf, c=
pudata->max_freq);
>
> +       WRITE_ONCE(cpudata->max_limit_perf, max_limit_perf);
> +       WRITE_ONCE(cpudata->min_limit_perf, min_limit_perf);
> +
>         max_perf =3D clamp_t(unsigned long, max_perf, cpudata->min_limit_=
perf,
>                         cpudata->max_limit_perf);
>         min_perf =3D clamp_t(unsigned long, min_perf, cpudata->min_limit_=
perf,
>                         cpudata->max_limit_perf);
> -
> -       WRITE_ONCE(cpudata->max_limit_perf, max_limit_perf);
> -       WRITE_ONCE(cpudata->min_limit_perf, min_limit_perf);
> -
>         value =3D READ_ONCE(cpudata->cppc_req_cached);
>
>         if (cpudata->policy =3D=3D CPUFREQ_POLICY_PERFORMANCE)
> --
> 2.34.1
>


--=20
Thanks & Regards
Wyes