[PATCH 28/70] drm/amd/display: Test plane color management update

From: Alex Hung <[email protected]>

[WHAT]
Add KUnit coverage for the legacy paths of
amdgpu_dm_update_plane_color_mgmt().

Using the shared color-update fixture, the tests cover the bad 3D LUT
size early failure, the default fallback path, implicit CRTC degamma
mapping, color caps taken from the DC context, and a plane CTM mapping to
the DPP gamut remap matrix.

Assisted-by: Copilot:Claude-Opus-4.8 GPT-5.5
Reviewed-by: Bhawanpreet Lakha <[email protected]>
Signed-off-by: Alex Hung <[email protected]>
Signed-off-by: Wayne Lin <[email protected]>
---
 .../amd/display/amdgpu_dm/amdgpu_dm_color.c   |   1 +
 .../amdgpu_dm/tests/amdgpu_dm_color_test.c    | 108 ++++++++++++++++++
 2 files changed, 109 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c
index 36aa4af581dd..dc1ad4325739 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c
@@ -2132,3 +2132,4 @@ int amdgpu_dm_update_plane_color_mgmt(struct dm_crtc_state *crtc,
 
 	return amdgpu_dm_plane_set_color_properties(plane_state, dc_plane_state);
 }
+EXPORT_IF_KUNIT(amdgpu_dm_update_plane_color_mgmt);
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_color_test.c b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_color_test.c
index 2e7a6b2a6d91..6bca2b2f62a8 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_color_test.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_color_test.c
@@ -1979,6 +1979,109 @@ static void dm_test_update_crtc_color_mgmt_ctm(struct kunit *test)
 	KUNIT_EXPECT_FALSE(test, f.stream->csc_color_matrix.enable_adjustment);
 }
 
+/**
+ * dm_test_update_plane_color_mgmt_bad_lut3d - Bad 3D LUT size fails early
+ * @test: KUnit test context
+ */
+static void dm_test_update_plane_color_mgmt_bad_lut3d(struct kunit *test)
+{
+	struct dm_test_color_update_fixture f = dm_test_color_update_setup(test);
+
+	f.adev->dm.dc->caps.color.dpp.hw_3d_lut = true;
+	f.dm_plane_state->lut3d = dm_test_make_lut_blob(test, 128);
+
+	KUNIT_EXPECT_EQ(test,
+		amdgpu_dm_update_plane_color_mgmt(f.crtc_state, &f.dm_plane_state->base,
+						  f.dc_plane_state),
+		-EINVAL);
+}
+
+/**
+ * dm_test_update_plane_color_mgmt_fallback_defaults - Legacy fallback default path
+ * @test: KUnit test context
+ */
+static void dm_test_update_plane_color_mgmt_fallback_defaults(struct kunit *test)
+{
+	struct dm_test_color_update_fixture f = dm_test_color_update_setup(test);
+
+	KUNIT_EXPECT_EQ(test,
+			amdgpu_dm_update_plane_color_mgmt(f.crtc_state, &f.dm_plane_state->base, f.dc_plane_state),
+			0);
+	KUNIT_EXPECT_EQ(test, f.dc_plane_state->hdr_mult.value, 0LL);
+	KUNIT_EXPECT_FALSE(test, f.dc_plane_state->cm.flags.bits.shaper_enable);
+	KUNIT_EXPECT_FALSE(test, f.dc_plane_state->cm.flags.bits.blend_enable);
+	KUNIT_EXPECT_FALSE(test, f.dc_plane_state->cm.flags.bits.lut3d_enable);
+	KUNIT_EXPECT_FALSE(test, f.dc_plane_state->gamut_remap_matrix.enable_remap);
+}
+
+/**
+ * dm_test_update_plane_color_mgmt_maps_crtc_degamma - CRTC implicit degamma path
+ * @test: KUnit test context
+ */
+static void dm_test_update_plane_color_mgmt_maps_crtc_degamma(struct kunit *test)
+{
+	struct dm_test_color_update_fixture f = dm_test_color_update_setup(test);
+
+	f.crtc_state->cm_is_degamma_srgb = true;
+
+	KUNIT_EXPECT_EQ(test,
+			amdgpu_dm_update_plane_color_mgmt(f.crtc_state, &f.dm_plane_state->base, f.dc_plane_state),
+			0);
+	KUNIT_EXPECT_EQ(test,
+			(int)f.dc_plane_state->in_transfer_func.type,
+			(int)TF_TYPE_PREDEFINED);
+	KUNIT_EXPECT_EQ(test,
+			(int)f.dc_plane_state->in_transfer_func.tf,
+			(int)TRANSFER_FUNCTION_SRGB);
+}
+
+/**
+ * dm_test_update_plane_color_mgmt_uses_color_caps - DC context provides color caps
+ * @test: KUnit test context
+ */
+static void dm_test_update_plane_color_mgmt_uses_color_caps(struct kunit *test)
+{
+	struct dm_test_color_update_fixture f = dm_test_color_update_setup(test);
+	struct dc_context *ctx;
+
+	ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, ctx);
+	ctx->dc = f.adev->dm.dc;
+	f.dc_plane_state->ctx = ctx;
+
+	KUNIT_EXPECT_EQ(test,
+			amdgpu_dm_update_plane_color_mgmt(f.crtc_state, &f.dm_plane_state->base, f.dc_plane_state),
+			0);
+}
+
+/**
+ * dm_test_update_plane_color_mgmt_plane_ctm - Plane CTM maps to gamut remap
+ * @test: KUnit test context
+ *
+ * When the plane has a CTM blob, the update path programs the DPP gamut
+ * remap matrix and enables remapping (and disables the input CSC).
+ */
+static void dm_test_update_plane_color_mgmt_plane_ctm(struct kunit *test)
+{
+	struct dm_test_color_update_fixture f = dm_test_color_update_setup(test);
+	struct drm_color_ctm_3x4 *ctm;
+
+	ctm = kunit_kzalloc(test, sizeof(*ctm), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, ctm);
+	/* Identity-ish entries; values are irrelevant to the branch taken. */
+	ctm->matrix[0] = 0x100000000ULL;
+	ctm->matrix[5] = 0x100000000ULL;
+	ctm->matrix[10] = 0x100000000ULL;
+
+	f.dm_plane_state->ctm = dm_test_make_ctm_blob(test, ctm, sizeof(*ctm));
+
+	KUNIT_EXPECT_EQ(test,
+			amdgpu_dm_update_plane_color_mgmt(f.crtc_state, &f.dm_plane_state->base, f.dc_plane_state),
+			0);
+	KUNIT_EXPECT_TRUE(test, f.dc_plane_state->gamut_remap_matrix.enable_remap);
+	KUNIT_EXPECT_FALSE(test, f.dc_plane_state->input_csc_color_matrix.enable_adjustment);
+}
+
 static struct kunit_case dm_color_test_cases[] = {
 	/* amdgpu_dm_fixpt_from_s3132 */
 	KUNIT_CASE(dm_test_fixpt_from_s3132_zero),
@@ -2096,6 +2199,11 @@ static struct kunit_case dm_color_test_cases[] = {
 	KUNIT_CASE(dm_test_check_crtc_color_mgmt_no_luts),
 	KUNIT_CASE(dm_test_update_crtc_color_mgmt_no_ctm),
 	KUNIT_CASE(dm_test_update_crtc_color_mgmt_ctm),
+	KUNIT_CASE(dm_test_update_plane_color_mgmt_bad_lut3d),
+	KUNIT_CASE(dm_test_update_plane_color_mgmt_fallback_defaults),
+	KUNIT_CASE(dm_test_update_plane_color_mgmt_maps_crtc_degamma),
+	KUNIT_CASE(dm_test_update_plane_color_mgmt_uses_color_caps),
+	KUNIT_CASE(dm_test_update_plane_color_mgmt_plane_ctm),
 	{}
 };
 
-- 
2.43.0