[v5 21/24] drm/i915/xelpd: Program Plane Post CSC Registers
Uma Shankar
uma.shankar at intel.com
Wed Jul 2 09:19:33 UTC 2025
From: Chaitanya Kumar Borah <chaitanya.kumar.borah at intel.com>
Extract the LUT and program plane post csc registers.
v2: Add DSB support
v3: Add support for single segment 1D LUT
Signed-off-by: Uma Shankar <uma.shankar at intel.com>
Signed-off-by: Chaitanya Kumar Borah <chaitanya.kumar.borah at intel.com>
---
drivers/gpu/drm/i915/display/intel_color.c | 123 +++++++++++++++++++++
1 file changed, 123 insertions(+)
diff --git a/drivers/gpu/drm/i915/display/intel_color.c b/drivers/gpu/drm/i915/display/intel_color.c
index 75981fe232bf..689bc4f4ce25 100644
--- a/drivers/gpu/drm/i915/display/intel_color.c
+++ b/drivers/gpu/drm/i915/display/intel_color.c
@@ -4041,11 +4041,134 @@ xelpd_program_plane_pre_csc_lut(struct intel_dsb *dsb,
}
}
+static void
+xelpd_program_plane_post_csc_lut(struct intel_dsb *dsb,
+ const struct intel_plane_state *plane_state)
+{
+ struct intel_display *display = to_intel_display(plane_state);
+ const struct drm_plane_state *state = &plane_state->uapi;
+ enum pipe pipe = to_intel_plane(state->plane)->pipe;
+ enum plane_id plane = to_intel_plane(state->plane)->id;
+ const struct drm_color_lut_32 *post_csc_lut = plane_state->hw.gamma_lut->data;
+ u32 i, lut_size, j;
+ bool is_single_seg = drm_color_lut_32_size(plane_state->hw.gamma_lut) == 32 ?
+ true : false;
+
+ if (icl_is_hdr_plane(display, plane)) {
+ intel_de_write_dsb(display, dsb, PLANE_POST_CSC_GAMC_INDEX_ENH(pipe, plane, 0),
+ PLANE_PAL_PREC_AUTO_INCREMENT);
+ /* TODO: Add macro */
+ intel_de_write_dsb(display, dsb, PLANE_POST_CSC_GAMC_SEG0_INDEX_ENH(pipe, plane, 0),
+ PLANE_PAL_PREC_AUTO_INCREMENT);
+ if (post_csc_lut) {
+ /* Segment 0 */
+ for (i = 0, j = 0; i < 9; i++, j++) {
+ if (is_single_seg)
+ break;
+
+ u32 lut_val = (post_csc_lut[j].green & 0xffffff);
+
+ intel_de_write_dsb(display, dsb,
+ PLANE_POST_CSC_GAMC_SEG0_DATA_ENH(pipe,
+ plane, 0),
+ lut_val);
+ }
+
+ /* Segment 1 */
+ lut_size = 32;
+ for (i = 0; i < lut_size; i++) {
+ u32 lut_val;
+
+ if (i == 0 && !is_single_seg)
+ lut_val = post_csc_lut[0].green & 0xffffff;
+ else if (i == 1 && !is_single_seg)
+ lut_val = (post_csc_lut[8].green & 0xffffff);
+ else
+ lut_val = is_single_seg ?
+ drm_color_lut_32_extract(post_csc_lut[j++].green,
+ 24)
+ : (post_csc_lut[j++].green & 0xffffff);
+
+ intel_de_write_dsb(display, dsb,
+ PLANE_POST_CSC_GAMC_DATA_ENH(pipe, plane, 0),
+ lut_val);
+ }
+
+ /* Segment 2 */
+ do {
+ intel_de_write_dsb(display, dsb,
+ PLANE_POST_CSC_GAMC_DATA_ENH(pipe, plane, 0),
+ is_single_seg ? (1 << 24) :
+ post_csc_lut[j].green);
+ } while (++j < (is_single_seg ? 34 : 42));
+ } else {
+ /*TODO: Add for segment 0 */
+ lut_size = 32;
+ for (i = 0; i < lut_size; i++) {
+ u32 v = (i * ((1 << 24) - 1)) / (lut_size - 1);
+
+ intel_de_write_dsb(display, dsb,
+ PLANE_POST_CSC_GAMC_DATA_ENH(pipe, plane, 0), v);
+ }
+
+ do {
+ intel_de_write_dsb(display, dsb,
+ PLANE_POST_CSC_GAMC_DATA_ENH(pipe, plane, 0),
+ 1 << 24);
+ } while (i++ < 34);
+ }
+
+ intel_de_write_dsb(display, dsb, PLANE_POST_CSC_GAMC_INDEX_ENH(pipe, plane, 0), 0);
+ intel_de_write_dsb(display, dsb,
+ PLANE_POST_CSC_GAMC_SEG0_INDEX_ENH(pipe, plane, 0), 0);
+ } else {
+ lut_size = 32;
+ /*
+ * First 3 planes are HDR, so reduce by 3 to get to the right
+ * SDR plane offset
+ */
+ plane = plane - 3;
+
+ intel_de_write_dsb(display, dsb, PLANE_POST_CSC_GAMC_INDEX(pipe, plane, 0),
+ PLANE_PAL_PREC_AUTO_INCREMENT);
+
+ if (post_csc_lut) {
+ for (i = 0; i < lut_size; i++)
+ intel_de_write_dsb(display, dsb,
+ PLANE_POST_CSC_GAMC_DATA(pipe, plane, 0),
+ post_csc_lut[i].green & 0xffff);
+ /* Program the max register to clamp values > 1.0. */
+ while (i < 35)
+ intel_de_write_dsb(display, dsb,
+ PLANE_POST_CSC_GAMC_DATA(pipe, plane, 0),
+ post_csc_lut[i++].green & 0x3ffff);
+ } else {
+ for (i = 0; i < lut_size; i++) {
+ u32 v = (i * ((1 << 16) - 1)) / (lut_size - 1);
+
+ intel_de_write_dsb(display, dsb,
+ PLANE_POST_CSC_GAMC_DATA(pipe, plane, 0), v);
+ }
+
+ do {
+ intel_de_write_dsb(display, dsb,
+ PLANE_POST_CSC_GAMC_DATA(pipe, plane, 0),
+ (1 << 16));
+ } while (i++ < 34);
+ }
+
+ intel_de_write_dsb(display, dsb, PLANE_POST_CSC_GAMC_INDEX(pipe, plane, 0), 0);
+ }
+}
+
static void
xelpd_plane_load_luts(struct intel_dsb *dsb, const struct intel_plane_state *plane_state)
{
if (plane_state->hw.degamma_lut)
xelpd_program_plane_pre_csc_lut(dsb, plane_state);
+
+ if (plane_state->hw.gamma_lut)
+ xelpd_program_plane_post_csc_lut(dsb, plane_state);
}
static const struct intel_color_funcs chv_color_funcs = {
--
2.42.0
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