Re: [PATCH v6 3/5] ACPI: CPPC: Make autonomous selection helpers take a u64

[Christian Loehle <christian.loehle@arm.com>]

On 10/20/26 13:18, 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 and driver unload through a common table of register
> get/set helpers that all take a u64. The bool autonomous selection
> helpers cannot be added to that table.
> 
> Change cppc_get_auto_sel()/cppc_set_auto_sel() to take a u64 so the
> autonomous selection register fits alongside the others, and update
> their callers.
> 
> Signed-off-by: Sumit Gupta <sumitg@nvidia.com>
> Reviewed-by: K Prateek Nayak <kprateek.nayak@amd.com>
> Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>

Reviewed-by: Christian Loehle <christian.loehle@arm.com>

> ---
>  drivers/acpi/cppc_acpi.c       | 20 ++++----------------
>  drivers/cpufreq/amd-pstate.c   |  2 +-
>  drivers/cpufreq/cppc_cpufreq.c |  4 ++--
>  include/acpi/cppc_acpi.h       |  8 ++++----
>  4 files changed, 11 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
> index 8d38924e0750..11a895fa9199 100644
> --- a/drivers/acpi/cppc_acpi.c
> +++ b/drivers/acpi/cppc_acpi.c
> @@ -3304,23 +3304,11 @@ EXPORT_SYMBOL_GPL(cppc_set_auto_act_window);
>  /**
>   * cppc_get_auto_sel() - Read autonomous selection register.
>   * @cpu: CPU from which to read register.
> - * @enable: Return address.
> + * @enable: Return address, set to 0 or 1.
>   */
> -int cppc_get_auto_sel(int cpu, bool *enable)
> +int cppc_get_auto_sel(int cpu, u64 *enable)
>  {
> -	u64 auto_sel;
> -	int ret;
> -
> -	if (enable == NULL)
> -		return -EINVAL;
> -
> -	ret = cppc_get_reg_val(cpu, AUTO_SEL_ENABLE, &auto_sel);
> -	if (ret)
> -		return ret;
> -
> -	*enable = (bool)auto_sel;
> -
> -	return 0;
> +	return cppc_get_reg_val(cpu, AUTO_SEL_ENABLE, enable);
>  }
>  EXPORT_SYMBOL_GPL(cppc_get_auto_sel);
>  
> @@ -3351,7 +3339,7 @@ EXPORT_SYMBOL_GPL(cppc_auto_sel_is_immutable);
>   * @cpu    : CPU to which to write register.
>   * @enable : the desired value of autonomous selection resiter to be updated.
>   */
> -int cppc_set_auto_sel(int cpu, bool enable)
> +int cppc_set_auto_sel(int cpu, u64 enable)
>  {
>  	return cppc_set_reg_val(cpu, AUTO_SEL_ENABLE, enable);
>  }
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index 4bedfbfc18b6..bf7d25e89d2a 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -546,7 +546,7 @@ static int shmem_init_perf(struct amd_cpudata *cpudata)
>  	struct cppc_perf_caps cppc_perf;
>  	union perf_cached perf = READ_ONCE(cpudata->perf);
>  	u64 numerator;
> -	bool auto_sel;
> +	u64 auto_sel;
>  
>  	int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf);
>  	if (ret)
> diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
> index 7448ca43b363..9e1214e1cb0d 100644
> --- a/drivers/cpufreq/cppc_cpufreq.c
> +++ b/drivers/cpufreq/cppc_cpufreq.c
> @@ -1059,7 +1059,7 @@ static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
>  
>  static ssize_t show_auto_select(struct cpufreq_policy *policy, char *buf)
>  {
> -	bool val;
> +	u64 val;
>  	int ret;
>  
>  	ret = cppc_get_auto_sel(policy->cpu, &val);
> @@ -1071,7 +1071,7 @@ static ssize_t show_auto_select(struct cpufreq_policy *policy, char *buf)
>  	if (ret)
>  		return ret;
>  
> -	return sysfs_emit(buf, "%d\n", val);
> +	return sysfs_emit(buf, "%llu\n", val);
>  }
>  
>  static ssize_t store_auto_select(struct cpufreq_policy *policy,
> diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h
> index 4495ee4ab71e..a5545fd3f8bd 100644
> --- a/include/acpi/cppc_acpi.h
> +++ b/include/acpi/cppc_acpi.h
> @@ -197,9 +197,9 @@ extern int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool e
>  extern int cppc_set_epp(int cpu, u64 epp_val);
>  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_get_auto_sel(int cpu, u64 *enable);
>  bool cppc_auto_sel_is_immutable(int cpu);
> -extern int cppc_set_auto_sel(int cpu, bool enable);
> +extern int cppc_set_auto_sel(int cpu, u64 enable);
>  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);
> @@ -298,7 +298,7 @@ static inline int cppc_set_auto_act_window(int cpu, u64 auto_act_window)
>  {
>  	return -EOPNOTSUPP;
>  }
> -static inline int cppc_get_auto_sel(int cpu, bool *enable)
> +static inline int cppc_get_auto_sel(int cpu, u64 *enable)
>  {
>  	return -EOPNOTSUPP;
>  }
> @@ -308,7 +308,7 @@ static inline bool cppc_auto_sel_is_immutable(int cpu)
>  	return false;
>  }
>  
> -static inline int cppc_set_auto_sel(int cpu, bool enable)
> +static inline int cppc_set_auto_sel(int cpu, u64 enable)
>  {
>  	return -EOPNOTSUPP;
>  }