The VIA DRM driver isn't yet ready with the patches going through review and needing to make some adjustments, which James Simmons still appears committed to seeing through and having his Direct Rendering Manager driver make it into the mainline tree.
Meanwhile, the Armada DRM driver also isn't ready and it isn't clear if there's enough motivation to get it mainlined. The Armada DRM display driver was written by Russell King, a well-known ARM Linux kernel developer, for the Marvell Armada 510 ARM SoCs. The driver supports multiple contiguous scanout buffers, shm-backed cacheable buffer objects for Vivante GPU acceleration, video overlays, and page-flipping.
While Russell has already pushed this Armada DRM driver through a few revisions in the past few weeks, he's facing criticism from DRM subsystem maintainer David Airlie over his patches. It appears Russell isn't too committed to seeing the driver merged, but if not, at least it could be picked up by OLPC developers or others who have a stake in Marvell Linux SoC support.
More information on the Armada DRM driver can be found out from the v4 patch series. At least the VIA DRM driver will hopefully be ready by Linux 3.12.