Best way to flip flop drivers

[jamey0824]

I want to alternate between fglrx and oss drivers, who has a good fast method of switching between them. Thanks.

[Kano]

Which debian/ubuntu switching is not that hard when you reboot and install/uninstall fglrx and reset the xorg.conf if needed. In that case i could help you. what distro do you use?

[grantek]

Yeah, building the fglrx .debs makes things really clean - basically what it does after being installed is:

$ dpkg-divert --list | grep fglrx
diversion of /usr/lib/libGL.so.1.2 to /usr/lib/fglrx/libGL.so.1.2.xlibmesa by xorg-driver-fglrx
diversion of /usr/lib/xorg/modules/extensions/libdri.so to /usr/lib/fglrx/libdri.so.xlibmesa by xorg-driver-fglrx
diversion of /usr/lib/xorg/modules/extensions/libglx.so to /usr/lib/fglrx/libglx.so.xlibmesa by xorg-driver-fglrx
diversion of /usr/lib32/libGL.so.1.2 to /usr/lib32/fglrx/libGL.so.1.2.xlibmesa by xorg-driver-fglrx

I believe if you wanted to have both installed at the same time you could set up a script to run dpkg-divert and swap those files around (that way you'd avoid having to do the DKMS compilation all the time). If that works, you could set up separate bootloader entries to pass a driver option as a kernel argument, then have a boot script do the file diversions and swap xorg.conf around.

I haven't tried any of this, but it'd be interesting to see if it works.

[Kano]

Thats incomplete, but basically it works like this. You have to disable the fglrx kernel module too. If you uninstall/install xorg-driver-fglrx together with fglrx-kernel-source it would be working too. Maybe removeing the depend of fglrx-kernel-source would be fine together with a backlist of fglrx (as it has the pciids visable just like a modesetting radeon driver). This is usually blacklisted in the initrd. That would not hurt usually, just check if fglrx starts with a blacklisted fglrx, in theory it should.

[Ant P.]

The way I did it was to use a separate boot option to load the last kernel I installed the fglrx module for, then run X with a separate xorg.conf in my home directory. The hard part is remembering to use the right libGL, but in gentoo that's easy to do (eselect opengl {ati,xorg-x11}). I guess the whole thing could be scripted based on whether fglrx.ko is present or not.

[Kano]

Sure, just try a:

echo blacklist fglrx > /etc/modprobe.d/fglrx.conf

[jamey0824]

Sorry for the late feedback

echo blacklist fglrx > /etc/modprobe.d/fglrx.conf[/QUOTE]

Kano: yes i am using ubuntu, is the above command the only thing i should need? Thanks