drm/amd/display: Test pre-GFX9 plane buffer attributes

[WHAT]
Add a KUnit test for amdgpu_dm_plane_fill_plane_buffer_attributes()
covering the pre-Vega dispatch to the GFX6 modifier decoder.

[HOW]
Run a GFX6-family framebuffer through a 1D tiled modifier and check
the decoded tiling version, then repeat with a GFX9 modifier to check
that the decode error is propagated instead.

Assisted-by: Copilot:Claude-Opus-5
Reviewed-by: Bhawanpreet Lakha <bhawanpreet.lakha@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Chenyu Chen <chen-yu.chen@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

0 files changed, 0 insertions, 0 deletions