On Wed, 11 Oct 2017 10:03:01 +0200 Geert Uytterhoeven wrote:
> PSCI support may be disabled at build time (by configuration) or at
> run-time (PSCI firmware not present). While CONFIG_ARM_PSCI_FW can be
> used to check for build time enablement, there is currently no simple
> way to check if PSCI is actually available and used.
>
> Hence add a helper function to check if PSCI is available.
>
> This is useful for e.g. drivers that are used on platforms with and
> without PSCI. Such drivers may need to take provisions for proper
> operation when PSCI is used, and/or to implement functionality that is
> usually provided by PSCI.
the psci_ops is a global var, why not check psci_ops.mmnn members
individually in each drivers? check IS_ENABLED(CONFIG_ARM_PSCI_FW) for
building time ennoblement.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> ---
> drivers/firmware/psci.c | 5 +++++
> include/linux/psci.h | 2 ++
> 2 files changed, 7 insertions(+)
>
> diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c
> index da469c972b503f83..a3a11e2d8ffffaaa 100644
> --- a/drivers/firmware/psci.c
> +++ b/drivers/firmware/psci.c
> @@ -670,6 +670,11 @@ int __init psci_dt_init(void)
> return init_fn(np);
> }
>
> +bool psci_is_available(void)
> +{
> + return psci_ops.cpu_off && psci_ops.cpu_on && psci_ops.cpu_suspend;
IIRC, for PSCI 0.1, cpu_suspend is optional, we can't say the PSCI isn't
available if cpu_suspend is missing.
Thanks
