Hi
On Mon, May 12, 2014 at 5:28 PM, Daniel Vetter daniel@ffwll.ch wrote:
Those are all just reasons for atomic modeset and maybe an atomic modeget ioctl which transfers the entire blob of things. Maybe we should start with the atomic modeget to get things rolling. Otoh you can always do that in userspace since we assume there's only one display manager.
DRM_MODE_OBJ_GET_PROPERTIES is already available and allows atomic retrieval of 'n' properties (as it calls drm_modeset_lock_all()). I guess that qualifies as what you describe with "atomic modeget"?
And for modeset we can throw efficiency of the marshalling/de-marshalling over board (within some limits of course) since we do about 60*num_pipes modeset/pageflip calls per second at most. And the overhead of the encoding/decoding of the properties will be completely washed out by all the register i/o we need to do to UC pci bars.
Yepp, I fully agree. And if properties turn out to become a bottleneck, we should optimize them.
Thanks David