[Intel-gfx] [PATCH] drm/i915: Don't initialize plane_to_crtc_mapping[] on SKL+

[Pandiyan, Dhinakaran]

On Mon, 2018-03-05 at 19:41 +0200, Ville Syrjala wrote:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> We don't use the enum i9xx_plane_id namespace on SKL+ anymore, so
> do not initialize the related plane_to_crtc_mapping[] table either.
> 
> Actually the only remaining user of that table is the pre-g4x
> watermark code, but no harm in initializing the table on all
> pre-SKL platforms.
> 
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> ---
>  drivers/gpu/drm/i915/intel_display.c | 15 +++++++++++----
>  1 file changed, 11 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index fb08590b4d40..435462bfc719 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -13572,10 +13572,17 @@ static int intel_crtc_init(struct drm_i915_private *dev_priv, enum pipe pipe)
>  	/* initialize shared scalers */
>  	intel_crtc_init_scalers(intel_crtc, crtc_state);
>  
> -	BUG_ON(pipe >= ARRAY_SIZE(dev_priv->plane_to_crtc_mapping) ||
> -	       dev_priv->plane_to_crtc_mapping[primary->i9xx_plane] != NULL);
> -	dev_priv->plane_to_crtc_mapping[primary->i9xx_plane] = intel_crtc;
> -	dev_priv->pipe_to_crtc_mapping[intel_crtc->pipe] = intel_crtc;
> +	BUG_ON(pipe >= ARRAY_SIZE(dev_priv->pipe_to_crtc_mapping) ||
> +	       dev_priv->pipe_to_crtc_mapping[pipe] != NULL);
> +	dev_priv->pipe_to_crtc_mapping[pipe] = intel_crtc;
> +
> +	if (INTEL_GEN(dev_priv) < 9) {
> +		enum i9xx_plane_id i9xx_plane = primary->i9xx_plane;
> +
> +		BUG_ON(i9xx_plane >= ARRAY_SIZE(dev_priv->plane_to_crtc_mapping) ||
> +		       dev_priv->plane_to_crtc_mapping[i9xx_plane] != NULL);
> +		dev_priv->plane_to_crtc_mapping[i9xx_plane] = intel_crtc;


Verified that plane_to_crtc_mapping[i9xx_plane] is used only in pre-gen9
code. Patch looks harmless 
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>

Should intel_get_crtc_for_plane be renamed to i9xx_get_crtc_for_plane()?
and the table as i9xx_plane_to_crtc_mapping[]?





> +	}
>  
>  	drm_crtc_helper_add(&intel_crtc->base, &intel_helper_funcs);
>