[Intel-gfx] [PATCH v8 4/8] drm/i915/guc: Introduce intel_guc_sanitize

[Chris Wilson]

Quoting Sagar Arun Kamble (2017-09-26 14:24:41)
> Currently GPU is reset at the end of suspend via i915_gem_sanitize.
> On resume, GuC will not be loaded until intel_uc_init_hw happens
> during GEM resume flow but action to exit sleep wll be send to GuC
> considering the FW load status. To make sure we don't invoke that
> action update GuC FW load status through new helper
> intel_guc_sanitize. Conditional check based on FW fetch status should
> take care of driver init flow.
> 
> v2: Rebase.
> 
> Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>
> Cc: Michał Winiarski <michal.winiarski at intel.com>
> Signed-off-by: Sagar Arun Kamble <sagar.a.kamble at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_gem.c | 2 ++
>  drivers/gpu/drm/i915/intel_uc.c | 8 ++++++++
>  drivers/gpu/drm/i915/intel_uc.h | 1 +
>  3 files changed, 11 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index 8e6e2bd..0d9a107 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -4528,6 +4528,8 @@ void i915_gem_sanitize(struct drm_i915_private *i915)
>                 mutex_unlock(&i915->drm.struct_mutex);
>         }
>  
> +       intel_guc_sanitize(&i915->guc);
> +
>         /*
>          * If we inherit context state from the BIOS or earlier occupants
>          * of the GPU, the GPU may be in an inconsistent state when we
> diff --git a/drivers/gpu/drm/i915/intel_uc.c b/drivers/gpu/drm/i915/intel_uc.c
> index b9376e4..29d43f8 100644
> --- a/drivers/gpu/drm/i915/intel_uc.c
> +++ b/drivers/gpu/drm/i915/intel_uc.c
> @@ -581,3 +581,11 @@ int intel_guc_sample_forcewake(struct intel_guc *guc)
>  
>         return intel_guc_send(guc, action, ARRAY_SIZE(action));
>  }
> +
> +void intel_guc_sanitize(struct intel_guc *guc)
> +{
> +       if (guc->fw.fetch_status == INTEL_UC_FIRMWARE_SUCCESS)
> +               guc->fw.load_status = INTEL_UC_FIRMWARE_PENDING;
> +       else
> +               guc->fw.load_status = INTEL_UC_FIRMWARE_NONE;

No, sanitize should not be carrying old state over. We are supposed to
be scrubbing hw state. (Elsewhere we detaint user state.)
-Chris