drm/amd/display: Fix Regamma end point

1. HW register programmed to wrong value
2. End slope for PQ case not calculated correctly

Signed-off-by: Anthony Koo <anthony.koo@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@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/calcs/gamma_calcs.c b/drivers/gpu/drm/amd/display/dc/calcs/gamma_calcs.c
index 5cd408d..f33135b 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/calcs/gamma_calcs.c
+++ b/drivers/gpu/drm/amd/display/dc/calcs/gamma_calcs.c
@@ -287,8 +287,6 @@ static bool build_hw_curve_configuration(
                uint32_t offset = 0;
                int8_t begin = curve_config->begin;
                int32_t region_number = 0;
-               struct fixed31_32 magic_number =
-                               dal_fixed31_32_from_fraction(249, 1000);
 
                i = begin;
 
@@ -370,10 +368,8 @@ static bool build_hw_curve_configuration(
                        ++i;
                }
 
-               points[index].x =
-                               dal_fixed31_32_add(region1, magic_number);
-               points[index].adjusted_x =
-                               dal_fixed31_32_add(region1, magic_number);
+               points[index].x = region1;
+               points[index].adjusted_x = region1;
 
                *number_of_points = index;
 
@@ -1218,7 +1214,8 @@ static void rebuild_curve_configuration_magic(
                struct curve_points *arr_points,
                struct pwl_result_data *rgb_resulted,
                const struct hw_x_point *coordinates_x,
-               uint32_t hw_points_num)
+               uint32_t hw_points_num,
+               enum dc_transfer_func_predefined tf)
 {
        struct fixed31_32 y_r;
        struct fixed31_32 y_g;
@@ -1264,6 +1261,18 @@ static void rebuild_curve_configuration_magic(
        arr_points[2].y = y3_max;
 
        arr_points[2].slope = dal_fixed31_32_zero;
+
+       /* for PQ, we want to have a straight line from last HW X point, and the
+        * slope to be such that we hit 1.0 at 10000 nits.
+        */
+       if (tf == TRANSFER_FUNCTION_PQ) {
+               const struct fixed31_32 end_value =
+                               dal_fixed31_32_from_int(125);
+
+               arr_points[2].slope = dal_fixed31_32_div(
+                       dal_fixed31_32_sub(dal_fixed31_32_one, arr_points[1].y),
+                       dal_fixed31_32_sub(end_value, arr_points[1].x));
+       }
 }
 
 static bool convert_to_custom_float_format(
@@ -1424,6 +1433,8 @@ bool calculate_regamma_params(struct pwl_params *params,
        struct pixel_gamma_point *coeff128_oem = NULL;
        struct pixel_gamma_point *coeff128 = NULL;
 
+       enum dc_transfer_func_predefined tf = TRANSFER_FUNCTION_SRGB;
+
        bool ret = false;
 
        coordinates_x = dm_alloc(sizeof(*coordinates_x)*(256 + 3));
@@ -1452,6 +1463,9 @@ bool calculate_regamma_params(struct pwl_params *params,
        dividers.divider2 = dal_fixed31_32_from_int(2);
        dividers.divider3 = dal_fixed31_32_from_fraction(5, 2);
 
+       if (stream->public.out_transfer_func)
+               tf = stream->public.out_transfer_func->tf;
+
        build_evenly_distributed_points(
                        axix_x_256,
                        256,
@@ -1460,8 +1474,7 @@ bool calculate_regamma_params(struct pwl_params *params,
 
        scale_gamma(rgb_user, ramp, dividers);
 
-       if (stream->public.out_transfer_func &&
-               stream->public.out_transfer_func->tf == TRANSFER_FUNCTION_PQ) {
+       if (tf == TRANSFER_FUNCTION_PQ) {
                setup_distribution_points_pq(arr_curve_points, arr_points,
                                &params->hw_points_num, coordinates_x,
                                surface->public.format);
@@ -1486,7 +1499,8 @@ bool calculate_regamma_params(struct pwl_params *params,
                        arr_points,
                        rgb_resulted,
                        coordinates_x,
-                       params->hw_points_num);
+                       params->hw_points_num,
+                       tf);
 
        convert_to_custom_float(rgb_resulted, arr_points,
                        params->hw_points_num);

diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_opp.c b/drivers/gpu/drm/amd/display/dc/dce/dce_opp.c
index 80443a1..653f93d 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dce/dce_opp.c
+++ b/drivers/gpu/drm/amd/display/dc/dce/dce_opp.c
@@ -139,8 +139,8 @@ static void regamma_config_regions_and_segments(
        }
        {
                REG_SET_2(REGAMMA_CNTLA_END_CNTL2, 0,
-                       REGAMMA_CNTLA_EXP_REGION_END_BASE, params->arr_points[2].custom_float_slope,
-                       REGAMMA_CNTLA_EXP_REGION_END_SLOPE, params->arr_points[1].custom_float_y);
+                       REGAMMA_CNTLA_EXP_REGION_END_BASE, params->arr_points[1].custom_float_y,
+                       REGAMMA_CNTLA_EXP_REGION_END_SLOPE, params->arr_points[2].custom_float_slope);
        }
 
        curve = params->arr_curve_points;