[PATCH 40/70] drm/amd/display: add CRC source verify KUnit coverage

From: Alex Hung <[email protected]>

[WHAT]
Expose amdgpu_dm_crtc_verify_crc_source() for KUnit and add tests for the
valid and invalid source-name paths. Introduce the shared CRTC test
scaffolding (dm_test_alloc_crc_crtc() plus the DM device test includes)
used by the remaining CRTC CRC tests.

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]>
---
 .../drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c |  1 +
 .../amdgpu_dm/tests/amdgpu_dm_crc_test.c      | 66 +++++++++++++++++++
 2 files changed, 67 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c
index 630dea3487b3..6600cc6ecf8e 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crc.c
@@ -565,6 +565,7 @@ amdgpu_dm_crtc_verify_crc_source(struct drm_crtc *crtc, const char *src_name,
 	*values_cnt = 3;
 	return 0;
 }
+EXPORT_IF_KUNIT(amdgpu_dm_crtc_verify_crc_source);
 
 int amdgpu_dm_crtc_configure_crc_source(struct drm_crtc *crtc,
 					struct dm_crtc_state *dm_crtc_state,
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_crc_test.c b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_crc_test.c
index 88f7a15853e8..4fa0bd9669c4 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_crc_test.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_crc_test.c
@@ -7,7 +7,30 @@
 
 #include <kunit/test.h>
 
+#include <drm/drm_modeset_lock.h>
+
+#include "dc.h"
+#include "amdgpu.h"
+#include "amdgpu_mode.h"
+#include "amdgpu_dm.h"
 #include "amdgpu_dm_crc.h"
+#include "amdgpu_dm_kunit_test_helpers.h"
+
+static struct amdgpu_crtc *dm_test_alloc_crc_crtc(struct kunit *test,
+							 struct amdgpu_device *adev)
+{
+	struct amdgpu_crtc *acrtc;
+
+	acrtc = kunit_kzalloc(test, sizeof(*acrtc), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, acrtc);
+
+	acrtc->base.dev = &adev->ddev;
+	drm_modeset_lock_init(&acrtc->base.mutex);
+	spin_lock_init(&acrtc->base.commit_lock);
+	INIT_LIST_HEAD(&acrtc->base.commit_list);
+
+	return acrtc;
+}
 
 static void dm_test_parse_crc_source_none(struct kunit *test)
 {
@@ -119,6 +142,46 @@ static void dm_test_crtc_get_crc_sources(struct kunit *test)
 	KUNIT_EXPECT_STREQ(test, sources[5], "auto");
 }
 
+/**
+ * dm_test_crtc_verify_crc_source_valid() - Test valid CRC source verification.
+ * @test: KUnit test context.
+ *
+ * Verifies that valid source strings return success and request three CRC
+ * values.
+ */
+static void dm_test_crtc_verify_crc_source_valid(struct kunit *test)
+{
+	struct amdgpu_device *adev = dm_kunit_alloc_adev(test);
+	struct amdgpu_crtc *acrtc = dm_test_alloc_crc_crtc(test, adev);
+	size_t values_cnt = 0;
+	int ret;
+
+	ret = amdgpu_dm_crtc_verify_crc_source(&acrtc->base, "crtc", &values_cnt);
+
+	KUNIT_EXPECT_EQ(test, ret, 0);
+	KUNIT_EXPECT_EQ(test, values_cnt, 3);
+}
+
+/**
+ * dm_test_crtc_verify_crc_source_invalid() - Test invalid CRC source verification.
+ * @test: KUnit test context.
+ *
+ * Verifies that invalid source strings are rejected without changing the
+ * caller-provided values count.
+ */
+static void dm_test_crtc_verify_crc_source_invalid(struct kunit *test)
+{
+	struct amdgpu_device *adev = dm_kunit_alloc_adev(test);
+	struct amdgpu_crtc *acrtc = dm_test_alloc_crc_crtc(test, adev);
+	size_t values_cnt = 7;
+	int ret;
+
+	ret = amdgpu_dm_crtc_verify_crc_source(&acrtc->base, "bad", &values_cnt);
+
+	KUNIT_EXPECT_EQ(test, ret, -EINVAL);
+	KUNIT_EXPECT_EQ(test, values_cnt, 7);
+}
+
 /**
  * dm_test_need_dp_aux() - Test dm_need_dp_aux().
  * @test: KUnit test context.
@@ -248,6 +311,9 @@ static struct kunit_case dm_crc_test_cases[] = {
 	KUNIT_CASE(dm_test_is_valid_crc_source),
 	/* amdgpu_dm_crtc_get_crc_sources() */
 	KUNIT_CASE(dm_test_crtc_get_crc_sources),
+	/* amdgpu_dm_crtc_verify_crc_source() */
+	KUNIT_CASE(dm_test_crtc_verify_crc_source_valid),
+	KUNIT_CASE(dm_test_crtc_verify_crc_source_invalid),
 	/* dm_need_dp_aux() */
 	KUNIT_CASE(dm_test_need_dp_aux),
 	/* dm_crc_source_should_start_dprx() */
-- 
2.43.0