[PATCH v4 1/3] ACPI: CPPC: Factor out and export per-cpu cppc_perf_ctrs_in_pcc_cpu()

[Rafael J. Wysocki]

On Wed, Dec 3, 2025 at 4:25 AM Jie Zhan <zhanjie9 at hisilicon.com> wrote:
>
> Factor out cppc_perf_ctrs_in_pcc_cpu() for checking whether per-cpu CPC
> regs are defined in PCC channels, and export it out for further use.
>
> Signed-off-by: Jie Zhan <zhanjie9 at hisilicon.com>
> ---
>  drivers/acpi/cppc_acpi.c | 45 +++++++++++++++++++++-------------------
>  include/acpi/cppc_acpi.h |  5 +++++
>  2 files changed, 29 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
> index 3bdeeee3414e..aa80dbcf42c0 100644
> --- a/drivers/acpi/cppc_acpi.c
> +++ b/drivers/acpi/cppc_acpi.c
> @@ -1422,6 +1422,29 @@ int cppc_get_perf_caps(int cpunum, struct cppc_perf_caps *perf_caps)
>  }
>  EXPORT_SYMBOL_GPL(cppc_get_perf_caps);
>
> +bool cppc_perf_ctrs_in_pcc_cpu(unsigned int cpu)
> +{
> +       struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpu);
> +       struct cpc_register_resource *ref_perf_reg;
> +
> +       /*
> +        * If reference perf register is not supported then we should use the
> +        * nominal perf value
> +        */
> +       ref_perf_reg = &cpc_desc->cpc_regs[REFERENCE_PERF];
> +       if (!CPC_SUPPORTED(ref_perf_reg))
> +               ref_perf_reg = &cpc_desc->cpc_regs[NOMINAL_PERF];
> +
> +       if (CPC_IN_PCC(&cpc_desc->cpc_regs[DELIVERED_CTR]) ||
> +           CPC_IN_PCC(&cpc_desc->cpc_regs[REFERENCE_CTR]) ||
> +           CPC_IN_PCC(&cpc_desc->cpc_regs[CTR_WRAP_TIME]) ||
> +           CPC_IN_PCC(ref_perf_reg))
> +               return true;
> +
> +       return false;

Why not

return CPC_IN_PCC(&cpc_desc->cpc_regs[DELIVERED_CTR]) ||
          CPC_IN_PCC(&cpc_desc->cpc_regs[REFERENCE_CTR]) ||
          CPC_IN_PCC(&cpc_desc->cpc_regs[CTR_WRAP_TIME]) ||
          CPC_IN_PCC(ref_perf_reg);

> +}
> +EXPORT_SYMBOL_GPL(cppc_perf_ctrs_in_pcc_cpu);
> +
>  /**
>   * cppc_perf_ctrs_in_pcc - Check if any perf counters are in a PCC region.
>   *
> @@ -1436,27 +1459,7 @@ bool cppc_perf_ctrs_in_pcc(void)
>         int cpu;
>
>         for_each_online_cpu(cpu) {
> -               struct cpc_register_resource *ref_perf_reg;
> -               struct cpc_desc *cpc_desc;
> -
> -               cpc_desc = per_cpu(cpc_desc_ptr, cpu);
> -
> -               if (CPC_IN_PCC(&cpc_desc->cpc_regs[DELIVERED_CTR]) ||
> -                   CPC_IN_PCC(&cpc_desc->cpc_regs[REFERENCE_CTR]) ||
> -                   CPC_IN_PCC(&cpc_desc->cpc_regs[CTR_WRAP_TIME]))
> -                       return true;
> -
> -
> -               ref_perf_reg = &cpc_desc->cpc_regs[REFERENCE_PERF];
> -
> -               /*
> -                * If reference perf register is not supported then we should
> -                * use the nominal perf value
> -                */
> -               if (!CPC_SUPPORTED(ref_perf_reg))
> -                       ref_perf_reg = &cpc_desc->cpc_regs[NOMINAL_PERF];
> -
> -               if (CPC_IN_PCC(ref_perf_reg))
> +               if (cppc_perf_ctrs_in_pcc_cpu(cpu))
>                         return true;
>         }
>
> diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h
> index 13fa81504844..4bcdcaf8bf2c 100644
> --- a/include/acpi/cppc_acpi.h
> +++ b/include/acpi/cppc_acpi.h
> @@ -154,6 +154,7 @@ 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);
>  extern int cppc_get_perf_caps(int cpu, struct cppc_perf_caps *caps);
> +extern bool cppc_perf_ctrs_in_pcc_cpu(unsigned int cpu);
>  extern bool cppc_perf_ctrs_in_pcc(void);
>  extern unsigned int cppc_perf_to_khz(struct cppc_perf_caps *caps, unsigned int perf);
>  extern unsigned int cppc_khz_to_perf(struct cppc_perf_caps *caps, unsigned int freq);
> @@ -204,6 +205,10 @@ static inline int cppc_get_perf_caps(int cpu, struct cppc_perf_caps *caps)
>  {
>         return -EOPNOTSUPP;
>  }
> +static inline bool cppc_perf_ctrs_in_pcc_cpu(unsigned int cpu)
> +{
> +       return false;
> +}
>  static inline bool cppc_perf_ctrs_in_pcc(void)
>  {
>         return false;
> --
> 2.33.0
>
>