Re: [Intel-gfx] [PATCH 13/20] drm/i915/dp: Reorder intel_dp_compute_config() a bit

[Nautiyal, Ankit K]

On 10/15/2021 7:09 PM, Ville Syrjala wrote:
From: Ville Syrjälä <ville.syrj...@linux.intel.com>

Consolidate the double pfit call, and reorder things so that
intel_dp_output_format() and intel_dp_compute_link_config() are
back-to-back. They are intimately related, and will need to be
called twice to properly handle the "4:2:0 also" modes.

Signed-off-by: Ville Syrjälä <ville.syrj...@linux.intel.com>
---
  drivers/gpu/drm/i915/display/intel_dp.c | 23 ++++++++++-------------
  1 file changed, 10 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c 
b/drivers/gpu/drm/i915/display/intel_dp.c
index 2440a6a2e4fc..de2b3d33a726 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -1764,25 +1764,12 @@ intel_dp_compute_config(struct intel_encoder *encoder,
        if (HAS_PCH_SPLIT(dev_priv) && !HAS_DDI(dev_priv) && encoder->port != 
PORT_A)
                pipe_config->has_pch_encoder = true;
  
-	pipe_config->output_format = intel_dp_output_format(&intel_connector->base,
-                                                           adjusted_mode);
-
-       if (pipe_config->output_format == INTEL_OUTPUT_FORMAT_YCBCR420) {
-               ret = intel_panel_fitting(pipe_config, conn_state);
-               if (ret)
-                       return ret;
-       }
-
        pipe_config->has_audio = intel_dp_has_audio(encoder, pipe_config, 
conn_state);
  
  	if (intel_dp_is_edp(intel_dp) && intel_connector->panel.fixed_mode) {
                ret = intel_panel_compute_config(intel_connector, 
adjusted_mode);
                if (ret)
                        return ret;
-
-               ret = intel_panel_fitting(pipe_config, conn_state);
-               if (ret)
-                       return ret;
        }
  
  	if (adjusted_mode->flags & DRM_MODE_FLAG_DBLSCAN)
@@ -1798,10 +1785,20 @@ intel_dp_compute_config(struct intel_encoder *encoder,
        if (intel_dp_hdisplay_bad(dev_priv, adjusted_mode->crtc_hdisplay))
                return -EINVAL;
  
+	pipe_config->output_format = intel_dp_output_format(&intel_connector->base,
+                                                           adjusted_mode);
+
        ret = intel_dp_compute_link_config(encoder, pipe_config, conn_state);
        if (ret < 0)
                return ret;
  
+	if ((intel_dp_is_edp(intel_dp) && intel_connector->panel.fixed_mode) ||
+           pipe_config->output_format == INTEL_OUTPUT_FORMAT_YCBCR420) {
+               ret = intel_panel_fitting(pipe_config, conn_state);

Panel fitting code will perhaps need handling for Big joiner.

In case of bigjoiner, we might need to set the pch_pfit->dest width 
halved, otherwise we might have scaler width going out of bound.

Now that we already have pipe_config->bigjoiner set, we can use it in 
pch_panel_fitting( ) to tweak dest width.

Something like 
https://github.com/aknautiyal/drm-tip/commit/c15060be2eca81738f8f0d3431e04215777edfc9

Regards,

Ankit

+               if (ret)
+                       return ret;
+       }
+
        pipe_config->limited_color_range =
                intel_dp_limited_color_range(pipe_config, conn_state);