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:
- dri2proto: c34ce137fdb21fc9a52bb8d5a0c25e3c5d79e687
- drm: 6293152eb065016a2e5e4fcd047c2db5c2fb0f36
- linux-2.6 (nouveau master)
f108a544dbc9b64b0b42cfc6e21bc4f5ffd38998
- mesa: dd3b98bdf67df9a5b1127bf7d50bbb6691597bfb
- xf86-video-nouveau:
13c10430ba8f7b0edff3ad8aae4a97672eea4a8f
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:
- Remove the
ModulePath directive from your
xorg.conf
- Remove the
nouveau_dri.so symlink from
/usr/lib/dri
- Possibly(?) boot into your previous kernel (I read grumblings
about ABI breakage on lkml which might mean that you can't use the
same libdrm with the old/new drivers, though I haven't had to find
out).
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.
- A standard compiz installation
- Basic 3d support
- Xvideo
- Display port switching with fn-F7 (but see below)
- Suspend/Resume (most of the time, anyway)
What still doesn't work
- Suspend/Resume doesn't /always/ work, I wouldn't call it 100%
reliable anyway
- I've had an occasional graphical lockup of the system requiring
reboot
- Switching display ports only partially works (one of the two
displays will usually be corrupted, though the other will work
ok).
- Docking and undocking combined with suspend/resume and
switching displays seems to trigger some hard lockups.
- Haven't tried extensive use of 3d-apps yet.
- Graphics glitches/artifacts
- A number of things will make compiz crash. When this happens it
automatically falls back to metacity, so it's not a huge
problem--just pretty annoying.
- gnome-display-properties
- using the compiz "Resize Window" plugin with "Normal" (change
it to "Rectangle")
- switching from lcd to external monitor will sometimes cause it
to crash
- I would guess other plugins might be problematic as well,
though at least what I had enabled previously seems to work
okay.
- Any kind of GPU power saving features (graphics card runs
pretty hot, anyway).
Further reading, references
Thanks
A couple shoutouts to those who helped me with this on the
way:
- all the developers involved in the respective projects... a big
Thank You!
- ymanton, mwk, calim, paerley on #nouveau for helping me
troubleshoot kernel/libdrm issues.
- KiBi on #debian-x for all the work getting nouveau into
unstable.
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).
Haskell provides type classes to support polymorphism. A type class defines a few methods, which can then be implemented for a concrete type in the type class instance. This is a powerful system, but it also has it drawbacks. Most notably, each type can have at most one implementation of the type class. But sometimes you need to use a different implementation.
If, for example, you used the 
This past week has had a couple of minor software releases:
I ve been AWOL for most of the debian project leader election campaigns this year, but I still want to vote, so I ve been dredging the emails on the last day. Maybe someone still has to vote and reads this, or maybe it ll help someone to interpret the result.
What I ve done this year is to make a quick tally of platform points and campaign answers that I liked and disliked for each candidate, then total them up to get an order. If anyone gets a negative (more dislikes than likes), then I ll rank them below NOTA.
Platforms: 
Now is there a nice way to store additional information like current branch or
commit message along with that?
