[Intel-gfx] [PATCH 2/2] drm/i915: Rewrite IVB FDI bifurcation conflict checks

[Ander Conselvan De Oliveira]

(for the series)
Reviewed-by: Ander Conselvan de Oliveira <conselvan2 at gmail.com>

On Wed, 2015-03-11 at 18:52 +0200, ville.syrjala at linux.intel.com wrote:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> Ignore the current state of the pipe and just check crtc_state->enable
> and the number of FDI lanes required. This means we don't accidentally
> mistake the FDI lanes as being available of one of the pipes just
> happens to be disabled at the time of the check. Also we no longer
> consider pipe C to require FDI lanes when it's driving the eDP
> transcoder.
> 
> We also take the opportunity to make the code a bit nicer looking by
> hiding the ugly bits in the new pipe_required_fdi_lanes() function.
> 
> Cc: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira at intel.com>
> Cc: Daniel Vetter <daniel at ffwll.ch>
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> ---
>  drivers/gpu/drm/i915/intel_display.c | 29 +++++++++++++++--------------
>  1 file changed, 15 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 242a8a7..72e9816 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -3152,12 +3152,6 @@ static void intel_fdi_normal_train(struct drm_crtc *crtc)
>  			   FDI_FE_ERRC_ENABLE);
>  }
>  
> -static bool pipe_has_enabled_pch(struct intel_crtc *crtc)
> -{
> -	return crtc->base.state->enable && crtc->active &&
> -		crtc->config->has_pch_encoder;
> -}
> -
>  /* The FDI link training functions for ILK/Ibexpeak. */
>  static void ironlake_fdi_link_train(struct drm_crtc *crtc)
>  {
> @@ -5548,13 +5542,21 @@ bool intel_connector_get_hw_state(struct intel_connector *connector)
>  	return encoder->get_hw_state(encoder, &pipe);
>  }
>  
> +static int pipe_required_fdi_lanes(struct drm_device *dev, enum pipe pipe)
> +{
> +	struct intel_crtc *crtc =
> +		to_intel_crtc(intel_get_crtc_for_pipe(dev, pipe));
> +
> +	if (crtc->base.state->enable &&
> +	    crtc->config->has_pch_encoder)
> +		return crtc->config->fdi_lanes;
> +
> +	return 0;
> +}
> +
>  static bool ironlake_check_fdi_lanes(struct drm_device *dev, enum pipe pipe,
>  				     struct intel_crtc_state *pipe_config)
>  {
> -	struct drm_i915_private *dev_priv = dev->dev_private;
> -	struct intel_crtc *pipe_B_crtc =
> -		to_intel_crtc(dev_priv->pipe_to_crtc_mapping[PIPE_B]);
> -
>  	DRM_DEBUG_KMS("checking fdi config on pipe %c, lanes %i\n",
>  		      pipe_name(pipe), pipe_config->fdi_lanes);
>  	if (pipe_config->fdi_lanes > 4) {
> @@ -5581,8 +5583,8 @@ static bool ironlake_check_fdi_lanes(struct drm_device *dev, enum pipe pipe,
>  	case PIPE_A:
>  		return true;
>  	case PIPE_B:
> -		if (dev_priv->pipe_to_crtc_mapping[PIPE_C]->enabled &&
> -		    pipe_config->fdi_lanes > 2) {
> +		if (pipe_config->fdi_lanes > 2 &&
> +		    pipe_required_fdi_lanes(dev, PIPE_C) > 0) {
>  			DRM_DEBUG_KMS("invalid shared fdi lane config on pipe %c: %i lanes\n",
>  				      pipe_name(pipe), pipe_config->fdi_lanes);
>  			return false;
> @@ -5594,8 +5596,7 @@ static bool ironlake_check_fdi_lanes(struct drm_device *dev, enum pipe pipe,
>  				      pipe_name(pipe), pipe_config->fdi_lanes);
>  			return false;
>  		}
> -		if (pipe_has_enabled_pch(pipe_B_crtc) &&
> -		    pipe_B_crtc->config->fdi_lanes > 2) {
> +		if (pipe_required_fdi_lanes(dev, PIPE_B) > 2) {
>  			DRM_DEBUG_KMS("fdi link B uses too many lanes to enable link C\n");
>  			return false;
>  		}