I guess that the time has finally come to admit that, as far as upstream development is concerned, the Geode X.Org driver is reaching retirement age:
While there have indeed been recent contributions by a number of developers to keep it compilable against recent X releases, the Geode driver has accumulated too much cruft from the Cyrix and NSC days, and it hasn't seen any active contribution from AMD in a long time. Besides, nowadays, Xserver pretty much assumes that its runs on an X driver that leverages its matching kernel driver and thus won't require root priviledges to launch. This isn't the case with the Geode driver, since it directly probes FBDEV and MSR, both of which reside in /dev and require root priviledges to access.
On Debian, as a stopgap measure, the package now Recommends a legacy wrapper that enforces operation as root. Meanwhile, other distributions are mercilessly droping all X drivers that don't leverage KMS. Basically, unless a miracle happens really quick, Geode will soon become unusable on X.
Back when AMD was still involved, a concensus had been reached that, since the Geode series doesn't offer any sort of advanced graphic capabilities, the most sensible option would indeed be to make a KMS driver and let Xserver use its generic modeline driver on top of that, then drop the Geode X driver entirely. Amazingly enough, someone did start working on a KMS driver for Geode LX, but it never made it as far as the Linux kernel tree (additionally, Gitorious seems to be down, but I have a copy of the driver's Git tree on hand, if anyone is interested). While I'll still be accepting and merging patches to the Geode X driver, our best long-term option would be to finalize the KMS driver and have it merged into Linux ASAP.