seanius.net/ blog/ 2010/ 04/   Nouveau, Gallium3D, and Compiz on Debian

update: 20100503: It's been brought to my attention that there might have been a regression in one of the libraries, mesa, maybe, so that master might not be as reliable a reference point for this guide. so, just in case, here are the commit hashes that were used from the different projects:

for the non-git-savvy: git checkout -b mybranch <hash>

we now return to your regular broadcasting...

A week or two ago I figured it was about time that I took the plung and tried out the latest nouveau drivers from experimental on my laptop. Unfortunately, it meant bidding adieu to compiz (apart from the bling it does actually provide some pretty damned useful features). I thought I'd give it a shot at least for a while on principal, since I've always had to think of the nvidia drivers as a necessary evil, and their lack of proper xrandr support is really, really annoying.

Since then I haven't noticed any problems, apart from the following message after every suspend/resume:

[  931.213239] Uhhuh. NMI received for unknown reason 80 on CPU 0.
[  931.213240] You have some hardware problem, likely on the PCI bus.
[  931.213242] Dazed and confused, but trying to continue

No idea what's causing it, but otherwise the system is stable and functional. If anyone knows what can be done about this, I'd appreciate hearing from you.

My graphics card, by the way:

01:00.0 VGA compatible controller: nVidia Corporation G72M [Quadro NVS 110M/GeForce Go 7300] (rev a1)

In the time since then, the nouveau driver has made its way into unstable, and a lot of distros (ubuntu, fedora, ...) are even using it as the default driver. So before going any further with the 3d/compiz stuff, I highly recommend that you get the packaged version working first. This will not only make sure that the basic driver works, but it will also make recovery/rollback a lot easier. Since it's all packaged in the standard repositories, it's not much harder than installing a few packages and editing a few files... so come on give it a try :)

Getting the 2d driver working in Debian sid

Really, this is so easy it's hardly worth writing up, but i'm running with the -v flag this morning...

Make sure you don't have any reference to nvidia in /etc/modules or other places that might cause it to be automatically loaded. Then remove the proprietary glx bindings, which would otherwise interfere with the nouveau driver.

sudo apt-get remove nvidia-glx

Next, you'll need to install a kernel that includes updated drm support. Normally this would require a kernel >= 2.6.33.1, but the debian kernel maintainers have graciously backported this code to the 2.6.32-4 kernel package. note this isn't the default kernel version in testing/unstable at the time of writing so you have to explicitly install it along with the nouveau driver.

sudo apt-get install linux-image-2.6.32-4-amd64 xserver-xorg-video-nouveau

If you are already running this kernel and using the proprietary nvidia drivers, via module-assistant or otherwise, you /might/ need to uninstall them first. On my system I left them installed in the old kernel version but did not install them on the new kernel version.

Required xorg configuration

I don't believe that nouveau is picked by default if available at the time of writing, so you have to have the following in your xorg.conf:

sudo sh -c "cat > /etc/X11/xorg.conf" << EOF
Section "Device"
    Identifier     "nVidia Corporation G72M [Quadro NVS 110M/GeForce Go 7300]"
    Driver         "nouveau"
EndSection
EOF

This was all I needed to do, apart from rebooting into the new kernel. For those who don't want to venture outside the packaging system, this is about as far as you can go for the time being. Though really, if you're bothering to read this far along, you're probably more interested in what comes next :)

Getting 3d working (without voiding your distro warranty)

So I thought I'd give the 3d-accelerated gallium a go. Their wiki page certainly makes one think twice, but at this point I was seriously fiending to get my bling back (well, the compiz scale plugin, anyway) and figured it wouldn't hurt too much to try.

Via google and trawling around in various forums I found a number of how-to documents for getting Gallium3d on debian/ubuntu systems, but most of them recommended doing things in a way that wasn't easily reversible and that could totally hose your system in a not-so-hypothetical worst-case scenario. It's pretty hard to roll back a make install done into /usr, for example, and subsequent package upgrades can leave your system even worse off as they will probably clobber half of what you just did, leaving the other half totally broken. And if you have a laptop which requires the gui for networking (i.e. network-manager), then fixing/rolling-back the changes is not entirely trivial, since you'd likely have to re-download the various drm/mesa/xorg packages.

So enter the tried and true unix utility stow (apt-get install stow, of course). stow is a utility that lets you install software into arbitrary folders, and then manage the system-wide installation of the software via a farm of symlinks pointing at the installed location. It's probably more well known among the sysadmin crowd than the desktop user crowd, but it's incredibly useful for the task at hand as it will let us easily install multiple copies of different software in a way that's very easy to update and/or roll-back. RTFM stow(1) for more information.

So, on to the juicy stuff...

Install needed software, remove problematic packages, setup, etc

At least on my system, I had to remove libdrm-dev to keep things from accidentally linking against it instead of the updated version that we install later on below. There's probably a way to override this with CFLAGS but I figure this is simpler.

sudo apt-get remove libdrm-dev
sudo apt-get install stow build-essential xorg-dev git-core libtool mesa-common-dev automake autoconf 
mkdir ~/nouveau

Compile a linux-2.6.34 RC kernel

cd ~/nouveau
git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
cd linux-2.6
git remote add -f nouveau git://anongit.freedesktop.org/nouveau/linux-2.6
git checkout -b nouveau-master nouveau/master
make menuconfig

Enable device drivers -> staging drivers -> nouveau. Make any other changes you might want to make (I just took defaults for everything else).

make deb-pkg

The linux-firmware-free debian package ships some of the same stuff from the generated linux-firmware-image package. I decided to opt for the upstream firmware, though I'm not sure that this is necessary:

sudo apt-get remove linux-firmware-free
sudo dpkg -i ~/nouveau/linux-image*.deb ~/nouveau/linux-firmware-image*.deb
sudo update-grub

Install a copy of dri2proto

cd ~/nouveau
git clone git://anongit.freedesktop.org/xorg/proto/dri2proto
cd dri2proto
./autogen.sh --prefix=/usr/local/stow/dri2proto-20100428
sudo mkdir -p /usr/local/stow/dri2proto-20100428
sudo make install
sudo stow -d /usr/local/stow dri2proto-20100428

Install a cutting-edge version of libdrm

cd ~/nouveau
git clone git://anongit.freedesktop.org/git/mesa/drm/
cd drm
./autogen.sh --prefix=/usr/local/stow/drm-20100428 --disable-intel --disable-radeon --enable-nouveau-experimental-api
make
sudo mkdir -p /usr/local/stow/drm-20100428
sudo make install
sudo stow  -d /usr/local/stow  drm-20100428

Likewise for mesa

cd ~/nouveau
git clone git://anongit.freedesktop.org/git/mesa/mesa
cd mesa
./autogen.sh --prefix=/usr/local/stow/mesa-20100428  --enable-debug --enable-glx-tls --disable-asm --with-dri-drivers= --enable-gallium-nouveau --disable-gallium-intel --disable-gallium-radeon --disable-gallium-svga --with-state-trackers=glx,dri --with-demos=xdemos,demos,trivial,tests
make
sudo mkdir -p /usr/local/stow/mesa-20100428 
sudo make install
sudo stow -d /usr/local/stow mesa-20100428

And now the xorg driver...

cd ~/nouveau
git clone git://anongit.freedesktop.org/git/nouveau/xf86-video-nouveau/
cd xf86-video-nouveau
./autogen.sh --prefix=/usr/local/stow/xf86-video-nouveau-20100428
make
sudo mkdir -p /usr/local/stow/xf86-video-nouveau-20100428
sudo make install
sudo stow -d /usr/local/stow xf86-video-nouveau-20100428

Configuration

Configure xorg to look in alternate location for xorg modules and set up DRI

sudo sh -c "cat > /etc/X11/xorg.conf" << EOF

Section "Files"
    ModulePath "/usr/local/lib/xorg/modules,/usr/lib/xorg/modules"
EndSection

Section "ServerFlags"
    Option "GlxVisuals" "all"
Endsection

Section "Device"
    Identifier     "nVidia Corporation G72M [Quadro NVS 110M/GeForce Go 7300]"
    Driver         "nouveau"
EndSection

EOF

I've /heard/ that disabling TV out is a necessity on some cards, though I haven't seen this myself:

sudo sh -c "cat > /etc/modprobe.d/nouveau.conf" << EOF
# not entirely sure this is necessary, but heard it helped with vsync
options nouveau tv_disable=1
EOF

Finally, the one thing that can not be done in /usr/local is making the nouveau DRI driver available. From what I could tell the path that mesa uses to find the DRI libraries is hard-coded (corrections welcome). Since you won't already have this file (otherwise, why would you be following along here?), just drop in a symlink to the file in /usr/local:

sudo ln -s /usr/local/lib/dri/nouveau_dri.so /usr/lib/dri/

Finally, reboot, and hope for the best :)

Riding the bleeding edge: how to upgrade later on

Again, stow really shows its usefullness here. Using drm as an example case, upgrading an individual component would look something like:

cd ~/nouveau/drm
git clean -dfx
git pull
today=`date +%Y%m%d`
./autogen.sh --prefix=/usr/local/stow/drm-$today --disable-intel --disable-radeon --enable-nouveau-experimental-api
make
sudo mkdir -p /usr/local/stow/drm-$today
sudo make install
sudo stow -d /usr/local/stow -D drm-20100428
sudo stow -d /usr/local/stow  drm-$today

Note how the old version is still installed, so you can switch components around pretty freely.

Abort! Abort!: How to roll back changes

In case your system becomes totally unusable, or you've decided that you just want to go back to the safe and cozy world of what's provided by the debian packages, simply do the following:

Assuming that you're using the nouveau driver from unstable, this should be all that is necessary.

Conclusion

Overall impression

I am very, very happy with the resulting setup. I was led to believe that this whole thing was much more unstable and unusable than it actually is! While there are certainly some glitches and missing features, I feel comfortable enough using it that I don't have plans to switch back. But if I find myself in a situation where I can't use the new setup, rolling back shouldn't be a problem either. I figure I'm happy with what I have now and it will only get better.

What works, at least to a "kinda works" level.

What still doesn't work

Further reading, references

Thanks

A couple shoutouts to those who helped me with this on the way:

Feedback / Corrections

Unforunately, I've had to disable comments for the time being due to overwhelming quantities of spam. So please drop me a line via email or on IRC (seanius on oftc/freenode).