RE: [PATCH V11 2/7] acpi: cppc: Add get the highest performance cppc control

From: Yuan, Perry
Date: Thu Nov 30 2023 - 01:02:12 EST


[AMD Official Use Only - General]

> -----Original Message-----
> From: Meng, Li (Jassmine) <Li.Meng@xxxxxxx>
> Sent: Wednesday, November 29, 2023 2:55 PM
> To: Rafael J . Wysocki <rafael.j.wysocki@xxxxxxxxx>; Huang, Ray
> <Ray.Huang@xxxxxxx>
> Cc: linux-pm@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; x86@xxxxxxxxxx;
> linux-acpi@xxxxxxxxxxxxxxx; Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>; linux-
> kselftest@xxxxxxxxxxxxxxx; Fontenot, Nathan <Nathan.Fontenot@xxxxxxx>;
> Sharma, Deepak <Deepak.Sharma@xxxxxxx>; Deucher, Alexander
> <Alexander.Deucher@xxxxxxx>; Limonciello, Mario
> <Mario.Limonciello@xxxxxxx>; Huang, Shimmer <Shimmer.Huang@xxxxxxx>;
> Yuan, Perry <Perry.Yuan@xxxxxxx>; Du, Xiaojian <Xiaojian.Du@xxxxxxx>;
> Viresh Kumar <viresh.kumar@xxxxxxxxxx>; Borislav Petkov <bp@xxxxxxxxx>;
> Oleksandr Natalenko <oleksandr@xxxxxxxxxxxxxx>; Meng, Li (Jassmine)
> <Li.Meng@xxxxxxx>; Karny, Wyes <Wyes.Karny@xxxxxxx>
> Subject: [PATCH V11 2/7] acpi: cppc: Add get the highest performance cppc
> control
>
> Add support for getting the highest performance to the generic CPPC driver. This
> enables downstream drivers such as amd-pstate to discover and use these
> values.
>
> Please refer to the ACPI_Spec for details on continuous performance control of
> CPPC.
>
> Tested-by: Oleksandr Natalenko <oleksandr@xxxxxxxxxxxxxx>
> Reviewed-by: Mario Limonciello <mario.limonciello@xxxxxxx>
> Reviewed-by: Wyes Karny <wyes.karny@xxxxxxx>
> Acked-by: Huang Rui <ray.huang@xxxxxxx>
> Signed-off-by: Meng Li <li.meng@xxxxxxx>
> Link:
> https://uefi.org/specs/ACPI/6.5/08_Processor_Configuration_and_Control.html?
> highlight=cppc#highest-performance
> ---
> drivers/acpi/cppc_acpi.c | 13 +++++++++++++ include/acpi/cppc_acpi.h | 5
> +++++
> 2 files changed, 18 insertions(+)
>
> diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index
> 7ff269a78c20..ad388a0e8484 100644
> --- a/drivers/acpi/cppc_acpi.c
> +++ b/drivers/acpi/cppc_acpi.c
> @@ -1154,6 +1154,19 @@ int cppc_get_nominal_perf(int cpunum, u64
> *nominal_perf)
> return cppc_get_perf(cpunum, NOMINAL_PERF, nominal_perf); }
>
> +/**
> + * cppc_get_highest_perf - Get the highest performance register value.
> + * @cpunum: CPU from which to get highest performance.
> + * @highest_perf: Return address.
> + *
> + * Return: 0 for success, -EIO otherwise.
> + */
> +int cppc_get_highest_perf(int cpunum, u64 *highest_perf) {
> + return cppc_get_perf(cpunum, HIGHEST_PERF, highest_perf); }
> +EXPORT_SYMBOL_GPL(cppc_get_highest_perf);
> +
> /**
> * cppc_get_epp_perf - Get the epp register value.
> * @cpunum: CPU from which to get epp preference value.
> diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h index
> 6126c977ece0..c0b69ffe7bdb 100644
> --- a/include/acpi/cppc_acpi.h
> +++ b/include/acpi/cppc_acpi.h
> @@ -139,6 +139,7 @@ struct cppc_cpudata { #ifdef CONFIG_ACPI_CPPC_LIB
> extern int cppc_get_desired_perf(int cpunum, u64 *desired_perf); extern int
> cppc_get_nominal_perf(int cpunum, u64 *nominal_perf);
> +extern int cppc_get_highest_perf(int cpunum, u64 *highest_perf);
> extern int cppc_get_perf_ctrs(int cpu, struct cppc_perf_fb_ctrs *perf_fb_ctrs);
> extern int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls); extern int
> cppc_set_enable(int cpu, bool enable); @@ -165,6 +166,10 @@ static inline int
> cppc_get_nominal_perf(int cpunum, u64 *nominal_perf) {
> return -ENOTSUPP;
> }
> +static inline int cppc_get_highest_perf(int cpunum, u64 *highest_perf)
> +{
> + return -ENOTSUPP;
> +}
> static inline int cppc_get_perf_ctrs(int cpu, struct cppc_perf_fb_ctrs
> *perf_fb_ctrs) {
> return -ENOTSUPP;
> --
> 2.34.1

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