[Intel-gfx] [PATCH 1/2] drm/i915: Clean up skl_plane_has_planar()

[Ville Syrjälä]

On Fri, Aug 24, 2018 at 01:38:55PM -0700, Dhinakaran Pandiyan wrote:
> skl_plane_has_planar is hard to read, simplify the logic by checking for
> support in the order of platform, pipe and plane.

I had a slightly different version of this somewhere. But this one might
be even better.

> 
> No change in functionality intended.
> 
> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_display.c | 27 +++++++++------------------
>  1 file changed, 9 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 30fdfd1a3037..7e18bd8b21b8 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -13622,24 +13622,15 @@ static bool skl_plane_has_fbc(struct drm_i915_private *dev_priv,
>  bool skl_plane_has_planar(struct drm_i915_private *dev_priv,
>  			  enum pipe pipe, enum plane_id plane_id)
>  {
> -	if (plane_id == PLANE_PRIMARY) {
> -		if (IS_SKYLAKE(dev_priv) || IS_BROXTON(dev_priv))
> -			return false;
> -		else if ((INTEL_GEN(dev_priv) == 9 && pipe == PIPE_C) &&
> -			 !IS_GEMINILAKE(dev_priv))
> -			return false;
> -	} else if (plane_id >= PLANE_SPRITE0) {
> -		if (plane_id == PLANE_CURSOR)
> -			return false;
> -		if (IS_GEMINILAKE(dev_priv) || INTEL_GEN(dev_priv) == 10) {
> -			if (plane_id != PLANE_SPRITE0)
> -				return false;
> -		} else {
> -			if (plane_id != PLANE_SPRITE0 || pipe == PIPE_C ||
> -			    IS_SKYLAKE(dev_priv) || IS_BROXTON(dev_priv))
> -				return false;
> -		}
> -	}
> +	if (IS_SKYLAKE(dev_priv) || IS_BROXTON(dev_priv))
> +		return false;
> +
> +	if (INTEL_GEN(dev_priv) == 9 && !IS_GEMINILAKE(dev_priv) && pipe == PIPE_C)
> +		return false;
> +
> +	if (plane_id == PLANE_CURSOR || plane_id != PLANE_SPRITE0)
> +		return false;

The cursor check is rather redundant here. IIRC I put it at the very
start of the function to make it obvious that cursor never supports
this. But we could just as well drop the check entirely.

This also disables NV12 for the primary plane which isn't correct.

> +
>  	return true;
>  }
>  
> -- 
> 2.17.1

-- 
Ville Syrjälä
Intel