[PATCH v6 5/7] drm/i915: Add dedicated plane hook for async flip case

[Ville Syrjälä]

On Fri, Aug 07, 2020 at 03:05:49PM +0530, Karthik B S wrote:
> This hook is added to avoid writing other plane registers in case of
> async flips, so that we do not write the double buffered registers
> during async surface address update.
> 
> Signed-off-by: Karthik B S <karthik.b.s at intel.com>
> Signed-off-by: Vandita Kulkarni <vandita.kulkarni at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_sprite.c | 25 +++++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_sprite.c b/drivers/gpu/drm/i915/display/intel_sprite.c
> index 2b2d96c59d7f..1c03546a4d2a 100644
> --- a/drivers/gpu/drm/i915/display/intel_sprite.c
> +++ b/drivers/gpu/drm/i915/display/intel_sprite.c
> @@ -609,6 +609,24 @@ icl_program_input_csc(struct intel_plane *plane,
>  			  PLANE_INPUT_CSC_POSTOFF(pipe, plane_id, 2), 0x0);
>  }
>  
> +static void
> +skl_program_async_surface_address(struct drm_i915_private *dev_priv,
> +				  const struct intel_plane_state *plane_state,
> +				  enum pipe pipe, enum plane_id plane_id,
> +				  u32 surf_addr)
> +{
> +	unsigned long irqflags;
> +	u32 plane_ctl = plane_state->ctl;

Need the bits from skl_plane_ctl_crtc() too.

> +
> +	spin_lock_irqsave(&dev_priv->uncore.lock, irqflags);
> +
> +	intel_de_write_fw(dev_priv, PLANE_CTL(pipe, plane_id), plane_ctl);
> +	intel_de_write_fw(dev_priv, PLANE_SURF(pipe, plane_id),
> +			  intel_plane_ggtt_offset(plane_state) + surf_addr);
> +
> +	spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags);
> +}
> +
>  static void
>  skl_program_plane(struct intel_plane *plane,
>  		  const struct intel_crtc_state *crtc_state,
> @@ -637,6 +655,13 @@ skl_program_plane(struct intel_plane *plane,
>  	u32 keymsk, keymax;
>  	u32 plane_ctl = plane_state->ctl;
>  
> +	/* During Async flip, no other updates are allowed */
> +	if (crtc_state->uapi.async_flip) {
> +		skl_program_async_surface_address(dev_priv, plane_state,
> +						  pipe, plane_id, surf_addr);
> +		return;
> +	}

I'd suggest adding a vfunc for this. Should be able to call it from
intel_update_plane(). That way we don't need to patch it into each
and every .update_plane() implementation.


> +
>  	plane_ctl |= skl_plane_ctl_crtc(crtc_state);
>  
>  	if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv))
> -- 
> 2.22.0

-- 
Ville Syrjälä
Intel