[PATCH 22/23] drm/i915/dp: Check src/sink compressed bpp limit for edp

[Ankit Nautiyal]

Use checks for src and sink limits before computing compressed bpp for
eDP.

Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
---
 drivers/gpu/drm/i915/display/intel_dp.c | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 97489958a27a..00f545b88398 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -2057,6 +2057,8 @@ static int intel_edp_dsc_compute_pipe_bpp(struct intel_dp *intel_dp,
 {
 	struct drm_i915_private *i915 = dp_to_i915(intel_dp);
 	int pipe_bpp, forced_bpp;
+	int dsc_src_min_bpp, dsc_sink_min_bpp, dsc_min_bpp;
+	int dsc_src_max_bpp, dsc_sink_max_bpp, dsc_max_bpp;
 
 	forced_bpp = intel_dp_force_dsc_pipe_bpp(intel_dp, conn_state, limits);
 
@@ -2074,9 +2076,21 @@ static int intel_edp_dsc_compute_pipe_bpp(struct intel_dp *intel_dp,
 	}
 	pipe_config->port_clock = limits->max_rate;
 	pipe_config->lane_count = limits->max_lane_count;
-	pipe_config->dsc.compressed_bpp =
-		min_t(u16, drm_edp_dsc_sink_output_bpp(intel_dp->dsc_dpcd) >> 4,
-		      pipe_bpp);
+
+	dsc_src_min_bpp = dsc_src_min_compressed_bpp();
+	dsc_sink_min_bpp = intel_dp_dsc_sink_min_compressed_bpp(pipe_config);
+	dsc_min_bpp = max(dsc_src_min_bpp, dsc_sink_min_bpp);
+
+	dsc_src_max_bpp = dsc_src_max_compressed_bpp(intel_dp);
+	dsc_sink_max_bpp = intel_dp_dsc_sink_max_compressed_bpp(intel_dp,
+								pipe_config,
+								pipe_bpp / 3);
+	dsc_max_bpp = dsc_sink_max_bpp ? min(dsc_sink_max_bpp, dsc_src_max_bpp) : dsc_src_max_bpp;
+
+	/* Compressed BPP should be less than the Input DSC bpp */
+	dsc_max_bpp = min(dsc_max_bpp, pipe_bpp - 1);
+
+	pipe_config->dsc.compressed_bpp = max(dsc_min_bpp, dsc_max_bpp);
 
 	pipe_config->pipe_bpp = pipe_bpp;
 
-- 
2.40.1