[PATCH] drm/i915/pxp/mtl: intel_pxp_init_hw needs runtime-pm inside pm-complete

[Ceraolo Spurio, Daniele]

On 6/1/2023 8:59 AM, Alan Previn wrote:
> In the case of failed suspend flow or cases where the kernel does not go
> into full suspend but goes from suspend_prepare back to resume_complete,
> we get called for a pm_complete but without runtime_pm guaranteed.
>
> Thus, ensure we take the runtime_pm when calling intel_pxp_init_hw
> from within intel_pxp_resume_complete.
>
> Signed-off-by: Alan Previn <alan.previn.teres.alexis at intel.com>
> ---
>   drivers/gpu/drm/i915/pxp/intel_pxp_pm.c | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_pm.c b/drivers/gpu/drm/i915/pxp/intel_pxp_pm.c
> index 1a04067f61fc..1d184dcd63c7 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp_pm.c
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_pm.c
> @@ -36,6 +36,8 @@ void intel_pxp_suspend(struct intel_pxp *pxp)
>   
>   void intel_pxp_resume_complete(struct intel_pxp *pxp)
>   {
> +	intel_wakeref_t wakeref;
> +
>   	if (!intel_pxp_is_enabled(pxp))
>   		return;
>   
> @@ -48,7 +50,8 @@ void intel_pxp_resume_complete()
>   	if (!HAS_ENGINE(pxp->ctrl_gt, GSC0) && !pxp->pxp_component)
>   		return;
>   
> -	intel_pxp_init_hw(pxp);
> +	with_intel_runtime_pm(&pxp->ctrl_gt->i915->runtime_pm, wakeref)

This is called from within the rpm resume path, so you can't do an rpm 
get or it will deadlock. Maybe have:

__pxp_resume_complete(struct intel_pxp *pxp, bool needs_rpm);

intel_pxp_resume_complete(..)
{
     return __pxp_resume_complete(pxp, true);
}

intel_pxp_runtime_resume(..)
{
     return __pxp_resume_complete(pxp, false);
}


or something like that.
Daniele

> +		intel_pxp_init_hw(pxp);
>   }
>   
>   void intel_pxp_runtime_suspend(struct intel_pxp *pxp)
>
> base-commit: a66da4c33d8ede541aea9ba6d0d73b556a072d54