[Intel-gfx] [PATCH] drm/i915/huc: Don't try to check HuC status if it's not loaded

[Chris Wilson]

Quoting Michal Wajdeczko (2019-05-17 22:40:28)
> If we never attempted to load HuC firmware, or we already wedged
> or reset GuC/HuC, then there is no reason to wake up the device
> to check one bit in the register that will be for sure cleared.
> 
> Suggested-by: Chris Wilson <chris at chris-wilson.co.uk>
> Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Tony Ye <tony.ye at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_huc.c | 3 +++
>  drivers/gpu/drm/i915/intel_huc.h | 5 +++++
>  2 files changed, 8 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/intel_huc.c b/drivers/gpu/drm/i915/intel_huc.c
> index 1ff1fb015e58..9d91089e2cd1 100644
> --- a/drivers/gpu/drm/i915/intel_huc.c
> +++ b/drivers/gpu/drm/i915/intel_huc.c
> @@ -163,6 +163,9 @@ int intel_huc_check_status(struct intel_huc *huc)
>         if (!HAS_HUC(dev_priv))
>                 return -ENODEV;
>  
> +       if (!intel_huc_is_loaded(huc))
> +               return 0;

Just to throw out an idea, -ENXIO?

A subtle change in ABI that should go unnoticed by the media driver, but
helps differentiate cause without having to dig deeper.
-Chris