Received-SPF: pass (google.com: domain of linux-kernel+bounces-215833-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1;
Precedence: bulk
MIME-Version: 1.0
References: <20240614193241.7341-1-mario.limonciello@amd.com>
In-Reply-To: <20240614193241.7341-1-mario.limonciello@amd.com>
From: "Rafael J. Wysocki" <rafael@kernel.org>
Date: Sat, 15 Jun 2024 12:38:02 +0200
Message-ID: <CAJZ5v0gMcR1wkOMkd5kHp8BZKdZd-HE9DrxByP9puCK-OUfGPA@mail.gmail.com>
Subject: Re: [PATCH] ACPI: Only evaluate the Intel _OSC and _PDC on platforms
 with HWP
To: Mario Limonciello <mario.limonciello@amd.com>
Cc: "Rafael J . Wysocki" <rafael@kernel.org>, "open list:ACPI" <linux-acpi@vger.kernel.org>, 
	open list <linux-kernel@vger.kernel.org>, 
	PradeepVineshReddy Kodamati <PradeepVineshReddy.Kodamati@amd.com>, CL Lin <clin41@lenovo.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

On Fri, Jun 14, 2024 at 9:33=E2=80=AFPM Mario Limonciello
<mario.limonciello@amd.com> wrote:
>
> The UUID 4077A616-290C-47BE-9EBD-D87058713953 and _PDC methods are
> only used on Intel platforms with HWP support.

I beg to differ.  See arch_acpi_set_proc_cap_bits() definition.

> Attempting to evaluate them and showing messages on hardware without
> HWP is pointless needlessly noisy.
>
> Gate the code on X86_FEATURE_HWP.

Not really.

> Cc: PradeepVineshReddy (Pradeep Vinesh Reddy) Kodamati <PradeepVineshRedd=
y.Kodamati@amd.com>
> Suggested-by: CL Lin <clin41@lenovo.com>
> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
> ---
>  drivers/acpi/acpi_processor.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.=
c
> index 7a0dd35d62c9..84848b5e65d6 100644
> --- a/drivers/acpi/acpi_processor.c
> +++ b/drivers/acpi/acpi_processor.c
> @@ -597,6 +597,8 @@ static bool __init acpi_early_processor_osc(void)
>
>  void __init acpi_early_processor_control_setup(void)
>  {
> +       if (!boot_cpu_has(X86_FEATURE_HWP))
> +               return;
>         if (acpi_early_processor_osc()) {
>                 pr_info("_OSC evaluated successfully for all CPUs\n");
>         } else {
> --
> 2.43.0
>