drm/amd/display: Add HLG support in color module

[Why & How]
Support hlg OETF and EOTF based on BT.2100-2
Follow up is required.

Signed-off-by: Vitaly Prosyak <vitaly.prosyak@amd.com>
Reviewed-by: Krunoslav Kovac <Krunoslav.Kovac@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Acked-by: Vitaly Prosyak <Vitaly.Prosyak@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/modules/color/color_gamma.c b/drivers/gpu/drm/amd/display/modules/color/color_gamma.c
index ac1be44766b269d090cc8565ab9ce78b7112fb05..6f853f2519d94225aee4979cb1b4282ce2ce26f5 100644 (file)
--- a/drivers/gpu/drm/amd/display/modules/color/color_gamma.c
+++ b/drivers/gpu/drm/amd/display/modules/color/color_gamma.c
@@ -30,7 +30,6 @@
 #include "opp.h"
 #include "color_gamma.h"
 
-
 #define NUM_PTS_IN_REGION 16
 #define NUM_REGIONS 32
 #define MAX_HW_POINTS (NUM_PTS_IN_REGION*NUM_REGIONS)
@@ -162,59 +161,68 @@ static void compute_de_pq(struct fixed31_32 in_x, struct fixed31_32 *out_y)
 
 }
 
+
 /*de gamma, none linear to linear*/
-static void compute_hlg_oetf(struct fixed31_32 in_x, bool is_light0_12, struct fixed31_32 *out_y)
+static void compute_hlg_eotf(struct fixed31_32 in_x,
+               struct fixed31_32 *out_y,
+               uint32_t sdr_white_level, uint32_t max_luminance_nits)
 {
        struct fixed31_32 a;
        struct fixed31_32 b;
        struct fixed31_32 c;
        struct fixed31_32 threshold;
-       struct fixed31_32 reference_white_level;
+       struct fixed31_32 x;
 
+       struct fixed31_32 scaling_factor =
+                       dc_fixpt_from_fraction(max_luminance_nits, sdr_white_level);
        a = dc_fixpt_from_fraction(17883277, 100000000);
-       if (is_light0_12) {
-               /*light 0-12*/
-               b = dc_fixpt_from_fraction(28466892, 100000000);
-               c = dc_fixpt_from_fraction(55991073, 100000000);
-               threshold = dc_fixpt_one;
-               reference_white_level = dc_fixpt_half;
+       b = dc_fixpt_from_fraction(28466892, 100000000);
+       c = dc_fixpt_from_fraction(55991073, 100000000);
+       threshold = dc_fixpt_from_fraction(1, 2);
+
+       if (dc_fixpt_lt(in_x, threshold)) {
+               x = dc_fixpt_mul(in_x, in_x);
+               x = dc_fixpt_div_int(x, 3);
        } else {
-               /*light 0-1*/
-               b = dc_fixpt_from_fraction(2372241, 100000000);
-               c = dc_fixpt_add(dc_fixpt_one, dc_fixpt_from_fraction(429347, 100000000));
-               threshold = dc_fixpt_from_fraction(1, 12);
-               reference_white_level = dc_fixpt_pow(dc_fixpt_from_fraction(3, 1), dc_fixpt_half);
+               x = dc_fixpt_sub(in_x, c);
+               x = dc_fixpt_div(x, a);
+               x = dc_fixpt_exp(x);
+               x = dc_fixpt_add(x, b);
+               x = dc_fixpt_div_int(x, 12);
        }
-       if (dc_fixpt_lt(threshold, in_x))
-               *out_y = dc_fixpt_add(c, dc_fixpt_mul(a, dc_fixpt_log(dc_fixpt_sub(in_x, b))));
-       else
-               *out_y = dc_fixpt_mul(dc_fixpt_pow(in_x, dc_fixpt_half), reference_white_level);
+       *out_y = dc_fixpt_mul(x, scaling_factor);
+
 }
 
 /*re gamma, linear to none linear*/
-static void compute_hlg_eotf(struct fixed31_32 in_x, bool is_light0_12, struct fixed31_32 *out_y)
+static void compute_hlg_oetf(struct fixed31_32 in_x, struct fixed31_32 *out_y,
+               uint32_t sdr_white_level, uint32_t max_luminance_nits)
 {
        struct fixed31_32 a;
        struct fixed31_32 b;
        struct fixed31_32 c;
-       struct fixed31_32 reference_white_level;
+       struct fixed31_32 threshold;
+       struct fixed31_32 x;
 
+       struct fixed31_32 scaling_factor =
+                       dc_fixpt_from_fraction(sdr_white_level, max_luminance_nits);
        a = dc_fixpt_from_fraction(17883277, 100000000);
-       if (is_light0_12) {
-               /*light 0-12*/
-               b = dc_fixpt_from_fraction(28466892, 100000000);
-               c = dc_fixpt_from_fraction(55991073, 100000000);
-               reference_white_level = dc_fixpt_from_fraction(4, 1);
+       b = dc_fixpt_from_fraction(28466892, 100000000);
+       c = dc_fixpt_from_fraction(55991073, 100000000);
+       threshold = dc_fixpt_from_fraction(1, 12);
+       x = dc_fixpt_mul(in_x, scaling_factor);
+
+
+       if (dc_fixpt_lt(x, threshold)) {
+               x = dc_fixpt_mul(x, dc_fixpt_from_fraction(3, 1));
+               *out_y = dc_fixpt_pow(x, dc_fixpt_half);
        } else {
-               /*light 0-1*/
-               b = dc_fixpt_from_fraction(2372241, 100000000);
-               c = dc_fixpt_add(dc_fixpt_one, dc_fixpt_from_fraction(429347, 100000000));
-               reference_white_level = dc_fixpt_from_fraction(1, 3);
+               x = dc_fixpt_mul(x, dc_fixpt_from_fraction(12, 1));
+               x = dc_fixpt_sub(x, b);
+               x = dc_fixpt_log(x);
+               x = dc_fixpt_mul(a, x);
+               *out_y = dc_fixpt_add(x, c);
        }
-       if (dc_fixpt_lt(dc_fixpt_half, in_x))
-               *out_y = dc_fixpt_add(dc_fixpt_exp(dc_fixpt_div(dc_fixpt_sub(in_x, c), a)), b);
-       else
-               *out_y = dc_fixpt_mul(dc_fixpt_pow(in_x, dc_fixpt_from_fraction(2, 1)), reference_white_level);
 }
 
 
@@ -1000,9 +1008,14 @@ release:
        return ret;
 }
 
+
+
+
+
 static void build_hlg_degamma(struct pwl_float_data_ex *degamma,
                uint32_t hw_points_num,
-               const struct hw_x_point *coordinate_x, bool is_light0_12)
+               const struct hw_x_point *coordinate_x,
+               uint32_t sdr_white_level, uint32_t max_luminance_nits)
 {
        uint32_t i;
 
@@ -1010,9 +1023,9 @@ static void build_hlg_degamma(struct pwl_float_data_ex *degamma,
        const struct hw_x_point *coord_x = coordinate_x;
 
        i = 0;
-
+       //check when i == 434
        while (i != hw_points_num + 1) {
-               compute_hlg_oetf(coord_x->x, is_light0_12, &rgb->r);
+               compute_hlg_eotf(coord_x->x, &rgb->r, sdr_white_level, max_luminance_nits);
                rgb->g = rgb->r;
                rgb->b = rgb->r;
                ++coord_x;
@@ -1021,9 +1034,11 @@ static void build_hlg_degamma(struct pwl_float_data_ex *degamma,
        }
 }
 
+
 static void build_hlg_regamma(struct pwl_float_data_ex *regamma,
                uint32_t hw_points_num,
-               const struct hw_x_point *coordinate_x, bool is_light0_12)
+               const struct hw_x_point *coordinate_x,
+               uint32_t sdr_white_level, uint32_t max_luminance_nits)
 {
        uint32_t i;
 
@@ -1032,8 +1047,9 @@ static void build_hlg_regamma(struct pwl_float_data_ex *regamma,
 
        i = 0;
 
+       //when i == 471
        while (i != hw_points_num + 1) {
-               compute_hlg_eotf(coord_x->x, is_light0_12, &rgb->r);
+               compute_hlg_oetf(coord_x->x, &rgb->r, sdr_white_level, max_luminance_nits);
                rgb->g = rgb->r;
                rgb->b = rgb->r;
                ++coord_x;
@@ -1919,7 +1935,7 @@ bool mod_color_calculate_degamma_params(struct dc_transfer_func *input_tf,
                build_hlg_degamma(curve,
                                MAX_HW_POINTS,
                                coordinates_x,
-                               true);
+                               80, 1000);
        else if (tf == TRANSFER_FUNCTION_LINEAR) {
                // just copy coordinates_x into curve
                i = 0;
@@ -2038,11 +2054,15 @@ bool  mod_color_calculate_curve(enum dc_transfer_func_predefined trans,
                                       GFP_KERNEL);
                if (!rgb_regamma)
                        goto rgb_regamma_alloc_fail;
+               points->end_exponent = 4;
+               points->x_point_at_y1_red = 12;
+               points->x_point_at_y1_green = 12;
+               points->x_point_at_y1_blue = 12;
 
                build_hlg_regamma(rgb_regamma,
                                MAX_HW_POINTS,
                                coordinates_x,
-                               true);
+                               80, 1000);
                for (i = 0; i <= MAX_HW_POINTS ; i++) {
                        points->red[i]    = rgb_regamma[i].r;
                        points->green[i]  = rgb_regamma[i].g;
@@ -2124,7 +2144,7 @@ bool  mod_color_calculate_degamma_curve(enum dc_transfer_func_predefined trans,
                build_hlg_degamma(rgb_degamma,
                                MAX_HW_POINTS,
                                coordinates_x,
-                               true);
+                               80, 1000);
                for (i = 0; i <= MAX_HW_POINTS ; i++) {
                        points->red[i]    = rgb_degamma[i].r;
                        points->green[i]  = rgb_degamma[i].g;