Adding support to overlay type in addition to primary and cursor plane. The planes composition relies on the z order of the active planes and only occurs if there is a primary plane (as in the current behavior).
The first patch decouples cursor from crtc_init. It initializes the CRTC only with primary plane, and setup the cursor plane externally. This is a preparation to allow to initialize the overlay plane between primary and cursor.
The second patch generalize variables and functions names to refer to any kind of plane, not only cursor. The goal is to reuse them for blending overlay and cursor planes to primary.
The third patch creates a module option to enable overlay, and includes overlay to supported types of plane. When the overlay option is enabled, one overlay plane is initialized (plus primary and cursor) and it is included in the planes composition.
This work preserves the current results of IGT tests: kms_cursor_crc; kms_flip and kms_writeback. In addition, subtests related to overlay in kms_atomic and kms_plane_cursor start to pass (pointed out in the commit message).
Melissa Wen (3): drm/vkms: decouple cursor plane setup from crtc_init drm/vkms: rename cursor to plane on ops of planes composition drm/vkms: add overlay support
drivers/gpu/drm/vkms/vkms_composer.c | 49 ++++++++++++++++------------ drivers/gpu/drm/vkms/vkms_crtc.c | 4 +-- drivers/gpu/drm/vkms/vkms_drv.c | 5 +++ drivers/gpu/drm/vkms/vkms_drv.h | 3 +- drivers/gpu/drm/vkms/vkms_output.c | 31 ++++++++++++++---- drivers/gpu/drm/vkms/vkms_plane.c | 20 +++++++++--- 6 files changed, 76 insertions(+), 36 deletions(-)