As we reported in December, the Nouveau driver is available in Ubuntu 9.04. Unlike Fedora 11 where the Nouveau driver is being enabled by default on NVIDIA hardware, the Nouveau driver will be an after-installation option to Ubuntu users. In this article are the simple steps on how to enabled the Nouveau driver in Ubuntu and what you can expect from this open-source, community-spawned graphics driver.
The Nouveau developers have been working on both the DDX X.Org driver with 2D and X-Video acceleration and then the 3D driver that is using the Gallium3D architecture. In the Ubuntu 9.04 release, only the DDX driver is an option but hopefully come time for Ubuntu 9.10 we will see the Gallium3D support in Ubuntu's Mesa stack. Mesa 7.5 is here, but by the time of the Karmic Koala we will ideally see Mesa 7.7/7.8 at least. The 3D support in Nouveau also varies quite a bit depending upon the NVIDIA ASIC and other factors.
Similar to the 3D situation, the Nouveau developers have mode-setting support in the traditional DDX driver but also they have already worked quite a bit on kernel mode-setting support. This Nouveau kernel mode-setting support is not yet in a released kernel and we probably will not see it be pushed into a mainline kernel until Linux 2.6.31 or more likely would be 2.6.32. It is possible we could see Nouveau kernel mode-setting in Ubuntu 9.10, but with the Jaunty Jackalope release it is limited to traditional mode-setting.
Acquiring the Nouveau driver on an Ubuntu 9.04 system just requires running sudo apt-get install xserver-xorg-video-nouveau. Besides fetching the xf86-video-nouveau driver, there is also a Nouveau-specific version of the libdrm that is needed as well as the Nouveau kernel module. Until there is the Nouveau support in a released kernel, there will be the nouveau-kernel-source package on Ubuntu for providing this support. The nouveau-kernel-source package uses DKMS (Dynamic Kernel Module Support) for automatically rebuilding the kernel module when you have upgraded or otherwise changed your Linux kernel.
Once the necessary packages are installed, the Nouveau driver needs to be set in the /etc/X11/xorg.conf file by adding Driver "nouveau" to the graphics card's device section. After that, reboot and you should be running with the Nouveau driver. An easy way to ensure you are running the Nouveau driver is by running cat /var/log/Xorg.0.log | grep NOUVEAU and then look at the output.
Even a novice Linux user can do this setup process within just a few minutes. While there is no 3D support for Nouveau in this Ubuntu release, the Nouveau driver is at least more actively being worked on than xf86-video-nv, which is the default NVIDIA driver in Ubuntu. While xf86-video-nv is the official open-source NVIDIA driver, it's 2D-only, ill maintained, contains a very slim set of features, and the code is intentionally obfuscated. In fact, there really have only been a few commits to the xf86-video-nv driver in the past several months.
The Nouveau driver still has a ways to go before seeing a stable release or the driver being feature-complete for any product generation, but they are making great progress and it is beginning to be picked up by more Linux distributions. General questions about the Nouveau driver can be asked in the Phoronix Forums.