[Intel-gfx] [PATCH] drm/i915/uc: Start preparing GuC/HuC for reset

[Michel Thierry]

On 22/02/18 10:45, Michal Wajdeczko wrote:
> Right after GPU reset there will be a small window of time during which
> some of GuC/HuC fields will still show state before reset. Let's start
> to fix that by sanitizing firmware status as we will use it shortly.
> 
> Suggested-by: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
> Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio at intel.com>
> Cc: Sagar Arun Kamble <sagar.a.kamble at intel.com>
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> ---
>   drivers/gpu/drm/i915/i915_gem.c    |  1 +
>   drivers/gpu/drm/i915/intel_guc.h   |  5 +++++
>   drivers/gpu/drm/i915/intel_huc.h   |  5 +++++
>   drivers/gpu/drm/i915/intel_uc.c    | 11 +++++++++++
>   drivers/gpu/drm/i915/intel_uc.h    |  1 +
>   drivers/gpu/drm/i915/intel_uc_fw.h |  6 ++++++
>   6 files changed, 29 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index 14c855b..9f91625 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -2981,6 +2981,7 @@ int i915_gem_reset_prepare(struct drm_i915_private *dev_priv)
>   	}
>   
>   	i915_gem_revoke_fences(dev_priv);
> +	intel_uc_reset_prepare(dev_priv);
>   
>   	return err;
>   }
> diff --git a/drivers/gpu/drm/i915/intel_guc.h b/drivers/gpu/drm/i915/intel_guc.h
> index 52856a9..ffa528f 100644
> --- a/drivers/gpu/drm/i915/intel_guc.h
> +++ b/drivers/gpu/drm/i915/intel_guc.h
> @@ -132,4 +132,9 @@ static inline u32 guc_ggtt_offset(struct i915_vma *vma)
>   struct i915_vma *intel_guc_allocate_vma(struct intel_guc *guc, u32 size);
>   u32 intel_guc_wopcm_size(struct drm_i915_private *dev_priv);
>   
> +static inline void intel_guc_reset_prepare(struct intel_guc *guc)

Hi,

Would intel_reset_guc_prepare be better?

Here you're preparing the guc for reset, not asking guc to prepare a reset.

For example, we have:
intel_guc_reset_engine  -> h2g requesting an engine reset
intel_reset_guc 	-> i915 will reset guc
gen9_reset_guc_interrupts -> i915 is resetting the iir reg

-Michel

> +{
> +	intel_uc_fw_reset_prepare(&guc->fw);
> +}
> +
>   #endif
> diff --git a/drivers/gpu/drm/i915/intel_huc.h b/drivers/gpu/drm/i915/intel_huc.h
> index 40039db..c1ee5b5 100644
> --- a/drivers/gpu/drm/i915/intel_huc.h
> +++ b/drivers/gpu/drm/i915/intel_huc.h
> @@ -38,4 +38,9 @@ struct intel_huc {
>   int intel_huc_init_hw(struct intel_huc *huc);
>   int intel_huc_auth(struct intel_huc *huc);
>   
> +static inline void intel_huc_reset_prepare(struct intel_huc *huc)

same here (for consistency).

> +{
> +	intel_uc_fw_reset_prepare(&huc->fw);
> +}
> +
>   #endif
> diff --git a/drivers/gpu/drm/i915/intel_uc.c b/drivers/gpu/drm/i915/intel_uc.c
> index 9f1bac6..64ae0a9 100644
> --- a/drivers/gpu/drm/i915/intel_uc.c
> +++ b/drivers/gpu/drm/i915/intel_uc.c
> @@ -445,3 +445,14 @@ void intel_uc_fini_hw(struct drm_i915_private *dev_priv)
>   	if (USES_GUC_SUBMISSION(dev_priv))
>   		gen9_disable_guc_interrupts(dev_priv);
>   }
> +
> +void intel_uc_reset_prepare(struct drm_i915_private *i915)
> +{
> +	if (!USES_GUC(i915))
> +		return;
> +
> +	GEM_BUG_ON(!HAS_GUC(i915));
> +
> +	intel_huc_reset_prepare(&i915->huc);
> +	intel_guc_reset_prepare(&i915->guc);
> +}
> diff --git a/drivers/gpu/drm/i915/intel_uc.h b/drivers/gpu/drm/i915/intel_uc.h
> index f2984e0..5c10253 100644
> --- a/drivers/gpu/drm/i915/intel_uc.h
> +++ b/drivers/gpu/drm/i915/intel_uc.h
> @@ -39,6 +39,7 @@
>   void intel_uc_fini_hw(struct drm_i915_private *dev_priv);
>   int intel_uc_init(struct drm_i915_private *dev_priv);
>   void intel_uc_fini(struct drm_i915_private *dev_priv);
> +void intel_uc_reset_prepare(struct drm_i915_private *dev_priv);
>   
>   static inline bool intel_uc_is_using_guc(void)
>   {
> diff --git a/drivers/gpu/drm/i915/intel_uc_fw.h b/drivers/gpu/drm/i915/intel_uc_fw.h
> index d5fd460..68bc304 100644
> --- a/drivers/gpu/drm/i915/intel_uc_fw.h
> +++ b/drivers/gpu/drm/i915/intel_uc_fw.h
> @@ -115,6 +115,12 @@ static inline bool intel_uc_fw_is_selected(struct intel_uc_fw *uc_fw)
>   	return uc_fw->path != NULL;
>   }
>   
> +static inline void intel_uc_fw_reset_prepare(struct intel_uc_fw *uc_fw)
> +{
> +	if (uc_fw->load_status == INTEL_UC_FIRMWARE_SUCCESS)
> +		uc_fw->load_status = INTEL_UC_FIRMWARE_PENDING;
> +}
> +
>   void intel_uc_fw_fetch(struct drm_i915_private *dev_priv,
>   		       struct intel_uc_fw *uc_fw);
>   int intel_uc_fw_upload(struct intel_uc_fw *uc_fw,
>