drm/amd/display: Rework DCE transform bit depth reduction programming.

Clear up the logic, and enable programming truncation as a bit reduction
mode.

Signed-off-by: Leo (Sunpeng) Li <sunpeng.li@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_transform.c b/drivers/gpu/drm/amd/display/dc/dce/dce_transform.c
index 6357546b49cd07313302c011b47f57cc3f1f4af4..ad411dac56395c0478809909e8e3495012f6f57f 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dce/dce_transform.c
+++ b/drivers/gpu/drm/amd/display/dc/dce/dce_transform.c
@@ -618,80 +618,48 @@ static void program_bit_depth_reduction(
        enum dc_color_depth depth,
        const struct bit_depth_reduction_params *bit_depth_params)
 {
-       enum dcp_bit_depth_reduction_mode depth_reduction_mode;
-       enum dcp_spatial_dither_mode spatial_dither_mode;
-       bool frame_random_enable;
-       bool rgb_random_enable;
-       bool highpass_random_enable;
+       enum dcp_out_trunc_round_depth trunc_round_depth;
+       enum dcp_out_trunc_round_mode trunc_mode;
+       bool spatial_dither_enable;
 
        ASSERT(depth < COLOR_DEPTH_121212); /* Invalid clamp bit depth */
 
-       if (bit_depth_params->flags.SPATIAL_DITHER_ENABLED) {
-               depth_reduction_mode = DCP_BIT_DEPTH_REDUCTION_MODE_DITHER;
-               frame_random_enable = true;
-               rgb_random_enable = true;
-               highpass_random_enable = true;
-
-       } else {
-               depth_reduction_mode = DCP_BIT_DEPTH_REDUCTION_MODE_DISABLED;
-               frame_random_enable = false;
-               rgb_random_enable = false;
-               highpass_random_enable = false;
+       spatial_dither_enable = bit_depth_params->flags.SPATIAL_DITHER_ENABLED;
+       /* Default to 12 bit truncation without rounding */
+       trunc_round_depth = DCP_OUT_TRUNC_ROUND_DEPTH_12BIT;
+       trunc_mode = DCP_OUT_TRUNC_ROUND_MODE_TRUNCATE;
+
+       if (bit_depth_params->flags.TRUNCATE_ENABLED) {
+               /* Don't enable dithering if truncation is enabled */
+               spatial_dither_enable = false;
+               trunc_mode = bit_depth_params->flags.TRUNCATE_MODE ?
+                            DCP_OUT_TRUNC_ROUND_MODE_ROUND :
+                            DCP_OUT_TRUNC_ROUND_MODE_TRUNCATE;
+
+               if (bit_depth_params->flags.TRUNCATE_DEPTH == 0 ||
+                   bit_depth_params->flags.TRUNCATE_DEPTH == 1)
+                       trunc_round_depth = DCP_OUT_TRUNC_ROUND_DEPTH_8BIT;
+               else if (bit_depth_params->flags.TRUNCATE_DEPTH == 2)
+                       trunc_round_depth = DCP_OUT_TRUNC_ROUND_DEPTH_10BIT;
+               else {
+                       /*
+                        * Invalid truncate/round depth. Setting here to 12bit
+                        * to prevent use-before-initialize errors.
+                        */
+                       trunc_round_depth = DCP_OUT_TRUNC_ROUND_DEPTH_12BIT;
+                       BREAK_TO_DEBUGGER();
+               }
        }
 
-       spatial_dither_mode = DCP_SPATIAL_DITHER_MODE_A_AA_A;
-
        set_clamp(xfm_dce, depth);
-
-       switch (depth_reduction_mode) {
-       case DCP_BIT_DEPTH_REDUCTION_MODE_DITHER:
-               /*  Spatial Dither: Set round/truncate to bypass (12bit),
-                *  enable Dither (30bpp) */
-               set_round(xfm_dce,
-                       DCP_OUT_TRUNC_ROUND_MODE_TRUNCATE,
-                       DCP_OUT_TRUNC_ROUND_DEPTH_12BIT);
-
-               set_dither(xfm_dce, true, spatial_dither_mode,
-                       DCP_SPATIAL_DITHER_DEPTH_30BPP, frame_random_enable,
-                       rgb_random_enable, highpass_random_enable);
-               break;
-       case DCP_BIT_DEPTH_REDUCTION_MODE_ROUND:
-               /*  Round: Enable round (10bit), disable Dither */
-               set_round(xfm_dce,
-                       DCP_OUT_TRUNC_ROUND_MODE_ROUND,
-                       DCP_OUT_TRUNC_ROUND_DEPTH_10BIT);
-
-               set_dither(xfm_dce, false, spatial_dither_mode,
-                       DCP_SPATIAL_DITHER_DEPTH_30BPP, frame_random_enable,
-                       rgb_random_enable, highpass_random_enable);
-               break;
-       case DCP_BIT_DEPTH_REDUCTION_MODE_TRUNCATE: /*  Truncate */
-               /*  Truncate: Enable truncate (10bit), disable Dither */
-               set_round(xfm_dce,
-                       DCP_OUT_TRUNC_ROUND_MODE_TRUNCATE,
-                       DCP_OUT_TRUNC_ROUND_DEPTH_10BIT);
-
-               set_dither(xfm_dce, false, spatial_dither_mode,
-                       DCP_SPATIAL_DITHER_DEPTH_30BPP, frame_random_enable,
-                       rgb_random_enable, highpass_random_enable);
-               break;
-
-       case DCP_BIT_DEPTH_REDUCTION_MODE_DISABLED: /*  Disabled */
-               /*  Truncate: Set round/truncate to bypass (12bit),
-                * disable Dither */
-               set_round(xfm_dce,
-                       DCP_OUT_TRUNC_ROUND_MODE_TRUNCATE,
-                       DCP_OUT_TRUNC_ROUND_DEPTH_12BIT);
-
-               set_dither(xfm_dce, false, spatial_dither_mode,
-                       DCP_SPATIAL_DITHER_DEPTH_30BPP, frame_random_enable,
-                       rgb_random_enable, highpass_random_enable);
-               break;
-       default:
-               /* Invalid DCP Depth reduction mode */
-               BREAK_TO_DEBUGGER();
-               break;
-       }
+       set_round(xfm_dce, trunc_mode, trunc_round_depth);
+       set_dither(xfm_dce,
+                  spatial_dither_enable,
+                  DCP_SPATIAL_DITHER_MODE_A_AA_A,
+                  DCP_SPATIAL_DITHER_DEPTH_30BPP,
+                  bit_depth_params->flags.FRAME_RANDOM,
+                  bit_depth_params->flags.RGB_RANDOM,
+                  bit_depth_params->flags.HIGHPASS_RANDOM);
 }
 
 static int dce_transform_get_max_num_of_supported_lines(