Re: [PATCH v2 2/3] ACPI: CPPC: Add u64 wrappers for the autonomous selection register

On 7/16/2026 11:38 PM, Sumit Gupta wrote:
> cppc_get_auto_sel()/cppc_set_auto_sel() use a bool, unlike the other
> CPPC register get/set helpers which use a u64.
> 
> The next patch in this series saves and restores the OSPM-set registers
> across CPU hotplug using a common table of get/set helpers typed as
> int (*)(int, u64 *) and int (*)(int, u64), which the bool autonomous
> selection helpers do not fit.
> 
> Add cppc_get_auto_sel_u64()/cppc_set_auto_sel_u64() wrappers with the u64
> signature so the autonomous selection register fits alongside the others.
> 
> Suggested-by: Pierre Gondois <[email protected]>
> Signed-off-by: Sumit Gupta <[email protected]>

If this is necessary, I think it is better to just change the input parameter
of the original cppc_get/set_auto_sel() to u64.

> ---
>  drivers/acpi/cppc_acpi.c | 40 ++++++++++++++++++++++++++++++++++++++++
>  include/acpi/cppc_acpi.h | 10 ++++++++++
>  2 files changed, 50 insertions(+)
> 
> diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
> index 9f572f481241..a7fec6c93178 100644
> --- a/drivers/acpi/cppc_acpi.c
> +++ b/drivers/acpi/cppc_acpi.c
> @@ -1788,6 +1788,46 @@ int cppc_set_auto_sel(int cpu, bool enable)
>  }
>  EXPORT_SYMBOL_GPL(cppc_set_auto_sel);
>  
> +/**
> + * cppc_get_auto_sel_u64 - Read the autonomous selection register as a u64.
> + * @cpu: CPU from which to read the register.
> + * @val: Return address, set to 0 or 1.
> + *
> + * u64-typed wrapper around cppc_get_auto_sel() for callers that keep CPPC
> + * register accessors in a common table.
> + *
> + * Return: 0 for success, -ERRNO otherwise.
> + */
> +int cppc_get_auto_sel_u64(int cpu, u64 *val)
> +{
> +	bool enable;
> +	int ret;
> +
> +	ret = cppc_get_auto_sel(cpu, &enable);
> +	if (ret)
> +		return ret;
> +
> +	*val = enable;
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(cppc_get_auto_sel_u64);
> +
> +/**
> + * cppc_set_auto_sel_u64 - Write the autonomous selection register from a u64.
> + * @cpu: CPU to which to write the register.
> + * @val: Value to write, any non-zero value enables autonomous selection.
> + *
> + * u64-typed wrapper around cppc_set_auto_sel().
> + *
> + * Return: 0 for success, -ERRNO otherwise.
> + */
> +int cppc_set_auto_sel_u64(int cpu, u64 val)
> +{
> +	return cppc_set_auto_sel(cpu, !!val);
> +}
> +EXPORT_SYMBOL_GPL(cppc_set_auto_sel_u64);
> +
>  /**
>   * cppc_set_enable - Set to enable CPPC on the processor by writing the
>   * Continuous Performance Control package EnableRegister field.
> diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h
> index 8693890a7275..cd07e1e92bf4 100644
> --- a/include/acpi/cppc_acpi.h
> +++ b/include/acpi/cppc_acpi.h
> @@ -184,6 +184,8 @@ extern int cppc_get_auto_act_window(int cpu, u64 *auto_act_window);
>  extern int cppc_set_auto_act_window(int cpu, u64 auto_act_window);
>  extern int cppc_get_auto_sel(int cpu, bool *enable);
>  extern int cppc_set_auto_sel(int cpu, bool enable);
> +extern int cppc_get_auto_sel_u64(int cpu, u64 *val);
> +extern int cppc_set_auto_sel_u64(int cpu, u64 val);
>  extern int cppc_get_perf_limited(int cpu, u64 *perf_limited);
>  extern int cppc_set_perf_limited(int cpu, u64 bits_to_clear);
>  extern int amd_get_highest_perf(unsigned int cpu, u32 *highest_perf);
> @@ -282,6 +284,14 @@ static inline int cppc_set_auto_sel(int cpu, bool enable)
>  {
>  	return -EOPNOTSUPP;
>  }
> +static inline int cppc_get_auto_sel_u64(int cpu, u64 *val)
> +{
> +	return -EOPNOTSUPP;
> +}
> +static inline int cppc_set_auto_sel_u64(int cpu, u64 val)
> +{
> +	return -EOPNOTSUPP;
> +}
>  static inline int cppc_get_perf_limited(int cpu, u64 *perf_limited)
>  {
>  	return -EOPNOTSUPP;