[PATCH v2 2/4] drm/komeda: Add drm_lut_to_fgamma_coeffs()

From: james qian wang (Arm Technology China)
Date: Fri Oct 11 2019 - 01:43:45 EST


This function is used to convert drm 3dlut to komeda HW required 1d curve
coeffs values.

Signed-off-by: james qian wang (Arm Technology China) <james.qian.wang@xxxxxxx>
---
.../arm/display/komeda/komeda_color_mgmt.c | 52 +++++++++++++++++++
.../arm/display/komeda/komeda_color_mgmt.h | 9 +++-
2 files changed, 60 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_color_mgmt.c b/drivers/gpu/drm/arm/display/komeda/komeda_color_mgmt.c
index 9d14a92dbb17..c180ce70c26c 100644
--- a/drivers/gpu/drm/arm/display/komeda/komeda_color_mgmt.c
+++ b/drivers/gpu/drm/arm/display/komeda/komeda_color_mgmt.c
@@ -65,3 +65,55 @@ const s32 *komeda_select_yuv2rgb_coeffs(u32 color_encoding, u32 color_range)

return coeffs;
}
+
+struct gamma_curve_sector {
+ u32 boundary_start;
+ u32 num_of_segments;
+ u32 segment_width;
+};
+
+struct gamma_curve_segment {
+ u32 start;
+ u32 end;
+};
+
+static struct gamma_curve_sector sector_tbl[] = {
+ { 0, 4, 4 },
+ { 16, 4, 4 },
+ { 32, 4, 8 },
+ { 64, 4, 16 },
+ { 128, 4, 32 },
+ { 256, 4, 64 },
+ { 512, 16, 32 },
+ { 1024, 24, 128 },
+};
+
+static void
+drm_lut_to_coeffs(struct drm_property_blob *lut_blob, u32 *coeffs,
+ struct gamma_curve_sector *sector_tbl, u32 num_sectors)
+{
+ struct drm_color_lut *lut;
+ u32 i, j, in, num = 0;
+
+ if (!lut_blob)
+ return;
+
+ lut = lut_blob->data;
+
+ for (i = 0; i < num_sectors; i++) {
+ for (j = 0; j < sector_tbl[i].num_of_segments; j++) {
+ in = sector_tbl[i].boundary_start +
+ j * sector_tbl[i].segment_width;
+
+ coeffs[num++] = drm_color_lut_extract(lut[in].red,
+ KOMEDA_COLOR_PRECISION);
+ }
+ }
+
+ coeffs[num] = BIT(KOMEDA_COLOR_PRECISION);
+}
+
+void drm_lut_to_fgamma_coeffs(struct drm_property_blob *lut_blob, u32 *coeffs)
+{
+ drm_lut_to_coeffs(lut_blob, coeffs, sector_tbl, ARRAY_SIZE(sector_tbl));
+}
diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_color_mgmt.h b/drivers/gpu/drm/arm/display/komeda/komeda_color_mgmt.h
index a2df218f58e7..08ab69281648 100644
--- a/drivers/gpu/drm/arm/display/komeda/komeda_color_mgmt.h
+++ b/drivers/gpu/drm/arm/display/komeda/komeda_color_mgmt.h
@@ -11,7 +11,14 @@
#include <drm/drm_color_mgmt.h>

#define KOMEDA_N_YUV2RGB_COEFFS 12
+#define KOMEDA_N_RGB2YUV_COEFFS 12
+#define KOMEDA_COLOR_PRECISION 12
+#define KOMEDA_N_GAMMA_COEFFS 65
+#define KOMEDA_COLOR_LUT_SIZE BIT(KOMEDA_COLOR_PRECISION)
+#define KOMEDA_N_CTM_COEFFS 9
+
+void drm_lut_to_fgamma_coeffs(struct drm_property_blob *lut_blob, u32 *coeffs);

const s32 *komeda_select_yuv2rgb_coeffs(u32 color_encoding, u32 color_range);

-#endif
+#endif /*_KOMEDA_COLOR_MGMT_H_*/
--
2.20.1