drm/amd/display: test native cursor mode on a disabled CRTC

[why]
Upstream has no KUnit coverage for amdgpu_dm_crtc_get_cursor_mode(),
which is why the fix in the previous commit came with no test. The
disabled-CRTC path is easy to regress again: it has already been lost
once to a refactor.

[how]
Add a test whose plane setup would otherwise select overlay mode, and
check that a disabled CRTC still reports native mode. Reverting the
previous commit makes only this test fail.

Reviewed-by: Wayne Lin <wayne.lin@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: James Lin <pinglei.lin@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_cursor_test.c b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_cursor_test.c
index f085eb1a616d..30fbacce0094 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_cursor_test.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_cursor_test.c
@@ -499,6 +499,27 @@ static void dm_test_plane_color_pipeline_ignores_other_plane(struct kunit *test)
 /* Tests for amdgpu_dm_crtc_get_cursor_mode() */
 
 /**
+ * dm_test_crtc_get_cursor_mode_disabled_crtc - Test a disabled CRTC uses native cursor
+ * @test: The KUnit test context
+ *
+ * A disabled CRTC must report native mode regardless of what the planes look
+ * like, so that a commit disabling the CRTC is not rejected. The plane setup
+ * here would otherwise select overlay mode.
+ */
+static void dm_test_crtc_get_cursor_mode_disabled_crtc(struct kunit *test)
+{
+	struct dm_cursor_mode_fixture fixture = dm_test_alloc_cursor_mode_fixture(test);
+	enum amdgpu_dm_cursor_mode cursor_mode = DM_CURSOR_OVERLAY_MODE;
+
+	fixture.dm_crtc_state->base.enable = false;
+	fixture.old_primary_state->crtc_w = 1280;
+	fixture.primary_state->crtc_w = 1280;
+
+	KUNIT_EXPECT_EQ(test, dm_test_get_cursor_mode(&fixture, &cursor_mode), 0);
+	KUNIT_EXPECT_EQ(test, cursor_mode, DM_CURSOR_NATIVE_MODE);
+}
+
+/**
  * dm_test_crtc_get_cursor_mode_new_hardware - Test new hardware always uses native mode
  * @test: The KUnit test context
  */
@@ -923,6 +944,7 @@ static struct kunit_case amdgpu_dm_cursor_tests[] = {
 	KUNIT_CASE(dm_test_plane_color_pipeline_active),
 	KUNIT_CASE(dm_test_plane_color_pipeline_ignores_other_plane),
 	/* amdgpu_dm_crtc_get_cursor_mode */
+	KUNIT_CASE(dm_test_crtc_get_cursor_mode_disabled_crtc),
 	KUNIT_CASE(dm_test_crtc_get_cursor_mode_new_hardware),
 	KUNIT_CASE(dm_test_crtc_get_cursor_mode_no_change),
 	KUNIT_CASE(dm_test_crtc_get_cursor_mode_disabled_cursor),