drm/i915/dp: Simplify computing forced DSC BPP for DP-SST

If dsc_compute_compressed_bpp() failed with a forced pipe BPP value
(where the forced pipe BPP value itself is valid within the min/max pipe
BPP limits), the function will also fail when called with the maximum
pipe BPP value: dsc_compute_compressed_bpp() will try all compressed
BPPs below the passed in pipe BPP value and if the function failed with
a given (low) compressed BPP value it will also fail with a compressed
BPP value higher than the one which failed already.

Based on the above remove the logic to retry computing a compressed BPP
value with the maximum pipe BPP value if computing the compressed BPP
failed already with the (lower) forced pipe BPP value.

Reviewed-by: Vinod Govindapillai <vinod.govindapillai@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patch.msgid.link/20251222153547.713360-18-imre.deak@intel.com

Author: ideak

drivers/gpu/drm/i915/display/intel_dp.c

@@ -2299,17 +2299,11 @@ static int intel_dp_dsc_compute_pipe_bpp(struct intel_dp *intel_dp,
 	int ret;
 
 	forced_bpp = intel_dp_force_dsc_pipe_bpp(intel_dp, limits);
+	if (forced_bpp)
+		pipe_bpp = forced_bpp;
+	else
+		pipe_bpp = limits->pipe.max_bpp;
 
-	if (forced_bpp) {
-		ret = dsc_compute_compressed_bpp(intel_dp, pipe_config, conn_state,
-						 limits, forced_bpp);
-		if (ret == 0) {
-			pipe_config->pipe_bpp = forced_bpp;
-			return 0;
-		}
-	}
-
-	pipe_bpp = limits->pipe.max_bpp;
 	ret = dsc_compute_compressed_bpp(intel_dp, pipe_config, conn_state,
 					 limits, pipe_bpp);
 	if (ret)