Re: [PATCH] ACPI: Only evaluate the Intel _OSC and _PDC on platforms with HWP

From: Rafael J. Wysocki
Date: Sat Jun 15 2024 - 06:38:23 EST


On Fri, Jun 14, 2024 at 9:33 PM Mario Limonciello
<mario.limonciello@xxxxxxx> 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 <PradeepVineshReddy.Kodamati@xxxxxxx>
> Suggested-by: CL Lin <clin41@xxxxxxxxxx>
> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
> ---
> 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
>