drm/amd/display: programming last delta in output transfer function LUT to a correct...

[Why]
Currently DAL programs negative slope for the last point of output
transfer function curve.

[How]
Applying a check for the last PWL point for RGB values not to be
smaller than previous. If smaller, initialize the last point values
to a sum of previous PWL value and previous PWL delta;

Signed-off-by: Vladimir Stempen <vladimir.stempen@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_cm_common.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_cm_common.c
index bbd6e01b3eca41df79079ce78bf426c6ee31c41b..47a39eb9400bb4dcd8a602478043124ed0cd6b29 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_cm_common.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_cm_common.c
@@ -316,6 +316,7 @@ bool cm_helper_translate_curve_to_hw_format(
        struct pwl_result_data *rgb_resulted;
        struct pwl_result_data *rgb;
        struct pwl_result_data *rgb_plus_1;
+       struct pwl_result_data *rgb_minus_1;
 
        int32_t region_start, region_end;
        int32_t i;
@@ -465,9 +466,20 @@ bool cm_helper_translate_curve_to_hw_format(
 
        rgb = rgb_resulted;
        rgb_plus_1 = rgb_resulted + 1;
+       rgb_minus_1 = rgb;
 
        i = 1;
        while (i != hw_points + 1) {
+
+               if (i >= hw_points - 1) {
+                       if (dc_fixpt_lt(rgb_plus_1->red, rgb->red))
+                               rgb_plus_1->red = dc_fixpt_add(rgb->red, rgb_minus_1->delta_red);
+                       if (dc_fixpt_lt(rgb_plus_1->green, rgb->green))
+                               rgb_plus_1->green = dc_fixpt_add(rgb->green, rgb_minus_1->delta_green);
+                       if (dc_fixpt_lt(rgb_plus_1->blue, rgb->blue))
+                               rgb_plus_1->blue = dc_fixpt_add(rgb->blue, rgb_minus_1->delta_blue);
+               }
+
                rgb->delta_red   = dc_fixpt_sub(rgb_plus_1->red,   rgb->red);
                rgb->delta_green = dc_fixpt_sub(rgb_plus_1->green, rgb->green);
                rgb->delta_blue  = dc_fixpt_sub(rgb_plus_1->blue,  rgb->blue);
@@ -482,6 +494,7 @@ bool cm_helper_translate_curve_to_hw_format(
                }
 
                ++rgb_plus_1;
+               rgb_minus_1 = rgb;
                ++rgb;
                ++i;
        }