Re: [PATCH v3 24/24] cpuidle: riscv-sbi: Drop redundant sync_state support

[Anup Patel <anup@brainfault.org>]

On Tue, Jul 1, 2025 at 5:18 PM Ulf Hansson <ulf.hansson@linaro.org> wrote:
>
> The recent updates to the genpd core, can entirely manage the sync_state
> support for the cpuidle-riscv-sbi-domain. More precisely, genpd prevents
> our ->power_off() callback from being invoked, until all of our consumers
> are ready for it.
>
> Let's therefore drop the sync_state support for the
> cpuidle-riscv-sbi-domain as it has become redundant.
>
> Cc: Anup Patel <anup@brainfault.org>
> Cc: linux-riscv@lists.infradead.org
> Tested-by: Hiago De Franco <hiago.franco@toradex.com> # Colibri iMX8X
> Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> # TI AM62A,Xilinx ZynqMP ZCU106
> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

LGTM.

Reviewed-by: Anup Patel <anup@brainfault.org>

Regards,
Anup

> ---
>  drivers/cpuidle/cpuidle-riscv-sbi.c | 22 +---------------------
>  1 file changed, 1 insertion(+), 21 deletions(-)
>
> diff --git a/drivers/cpuidle/cpuidle-riscv-sbi.c b/drivers/cpuidle/cpuidle-riscv-sbi.c
> index 83d58d00872f..a360bc4d20b7 100644
> --- a/drivers/cpuidle/cpuidle-riscv-sbi.c
> +++ b/drivers/cpuidle/cpuidle-riscv-sbi.c
> @@ -44,7 +44,6 @@ static DEFINE_PER_CPU_READ_MOSTLY(struct sbi_cpuidle_data, sbi_cpuidle_data);
>  static DEFINE_PER_CPU(struct sbi_domain_state, domain_state);
>  static bool sbi_cpuidle_use_osi;
>  static bool sbi_cpuidle_use_cpuhp;
> -static bool sbi_cpuidle_pd_allow_domain_state;
>
>  static inline void sbi_set_domain_state(u32 state)
>  {
> @@ -345,20 +344,6 @@ static int sbi_cpuidle_init_cpu(struct device *dev, int cpu)
>         return ret;
>  }
>
> -static void sbi_cpuidle_domain_sync_state(struct device *dev)
> -{
> -       struct sbi_pd_provider *pd_provider;
> -
> -       /*
> -        * All devices have now been attached/probed to the PM domain
> -        * topology, hence it's fine to allow domain states to be picked.
> -        */
> -       sbi_cpuidle_pd_allow_domain_state = true;
> -
> -       list_for_each_entry(pd_provider, &sbi_pd_providers, link)
> -               of_genpd_sync_state(pd_provider->node);
> -}
> -
>  #ifdef CONFIG_DT_IDLE_GENPD
>
>  static int sbi_cpuidle_pd_power_off(struct generic_pm_domain *pd)
> @@ -369,9 +354,6 @@ static int sbi_cpuidle_pd_power_off(struct generic_pm_domain *pd)
>         if (!state->data)
>                 return 0;
>
> -       if (!sbi_cpuidle_pd_allow_domain_state)
> -               return -EBUSY;
> -
>         /* OSI mode is enabled, set the corresponding domain state. */
>         pd_state = state->data;
>         sbi_set_domain_state(*pd_state);
> @@ -401,8 +383,7 @@ static int sbi_pd_init(struct device_node *np)
>         if (!pd_provider)
>                 goto free_pd;
>
> -       pd->flags |= GENPD_FLAG_IRQ_SAFE | GENPD_FLAG_CPU_DOMAIN |
> -                    GENPD_FLAG_NO_SYNC_STATE;
> +       pd->flags |= GENPD_FLAG_IRQ_SAFE | GENPD_FLAG_CPU_DOMAIN;
>
>         /* Allow power off when OSI is available. */
>         if (sbi_cpuidle_use_osi)
> @@ -570,7 +551,6 @@ static struct platform_driver sbi_cpuidle_driver = {
>         .probe = sbi_cpuidle_probe,
>         .driver = {
>                 .name = "sbi-cpuidle",
> -               .sync_state = sbi_cpuidle_domain_sync_state,
>         },
>  };
>
> --
> 2.43.0
>