[Intel-gfx] [RFC-v19 09/13] drm/i915/pxp: Expose session state for display protection flip

[Vivi, Rodrigo]

On Wed, 2021-01-06 at 15:12 -0800, Huang, Sean Z wrote:
> Implement the intel_pxp_gem_object_status() to allow i915 display
> querying the current PXP session state. In the design, display
> should not perform protection flip on the protected buffers if
> there is no PXP session alive. And Implement the funciton to set
> the protected flag for gem context.
> 
> Signed-off-by: Huang, Sean Z <sean.z.huang at intel.com>
> ---
>  drivers/gpu/drm/i915/pxp/intel_pxp.c | 21 +++++++++++++++++++++
>  drivers/gpu/drm/i915/pxp/intel_pxp.h | 18 ++++++++++++++++++
>  2 files changed, 39 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.c
> b/drivers/gpu/drm/i915/pxp/intel_pxp.c
> index 23d4cfc1fb1f..a28a459532c2 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp.c
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp.c
> @@ -158,3 +158,24 @@ void intel_pxp_irq_handler(struct intel_pxp
> *pxp, u16 iir)
>         pxp->current_events |= events;
>         schedule_work(&pxp->irq_work);
>  }
> +
> +bool intel_pxp_gem_object_status(struct drm_i915_private *i915)
> +{
> +       if (i915->gt.pxp.ctx.inited &&
> +           i915->gt.pxp.ctx.flag_display_hm_surface_keys)
> +               return true;
> +       else
> +               return false;
> +}
> +
> +int intel_pxp_gem_context_set_protected(struct drm_i915_private
> *i915,
> +                                       unsigned long *user_flags,
> +                                       u32 protected_bit)
> +{
> +       if (!user_flags || !protected_bit ||
> +           !intel_pxp_arb_session_is_in_play(&i915->gt.pxp))
> +               return -EINVAL;
> +
> +       set_bit(protected_bit, user_flags);

This protected_bit should only be set during context creation and never
modified with set_context.

> +       return 0;
> +}
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.h
> b/drivers/gpu/drm/i915/pxp/intel_pxp.h
> index cdaa6ce6fdca..ff1c1c0e720c 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp.h
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp.h
> @@ -29,6 +29,8 @@ enum pxp_protection_modes {
>         PROTECTION_MODE_ALL
>  };
>  
> +struct drm_i915_private;
> +
>  #ifdef CONFIG_DRM_I915_PXP
>  void intel_pxp_irq_handler(struct intel_pxp *pxp, u16 iir);
>  int i915_pxp_teardown_required_callback(struct intel_pxp *pxp);
> @@ -36,6 +38,10 @@ int
> i915_pxp_global_terminate_complete_callback(struct intel_pxp *pxp);
>  
>  void intel_pxp_init(struct intel_pxp *pxp);
>  void intel_pxp_fini(struct intel_pxp *pxp);
> +bool intel_pxp_gem_object_status(struct drm_i915_private *i915);
> +int intel_pxp_gem_context_set_protected(struct drm_i915_private
> *i915,
> +                                       unsigned long *user_flag,
> +                                       u32 protected_bit);
>  #else
>  static inline void intel_pxp_irq_handler(struct intel_pxp *pxp, u16
> iir)
>  {
> @@ -58,6 +64,18 @@ static inline void intel_pxp_init(struct intel_pxp
> *pxp)
>  static inline void intel_pxp_fini(struct intel_pxp *pxp)
>  {
>  }
> +
> +static inline bool intel_pxp_gem_object_status(struct
> drm_i915_private *i915)
> +{
> +       return false;
> +}
> +
> +static inline int intel_pxp_gem_context_set_protected(struct
> drm_i915_private *i915,
> +                                                     unsigned long
> *user_flag,
> +                                                     u32
> protected_bit)
> +{
> +       return 0;
> +}
>  #endif
>  
>  #endif /* __INTEL_PXP_H__ */