[Nouveau] Gallium driver and compatibility issues

[Uwe Bugla]

Am Freitag, den 12.03.2010, 16:19 +0100 schrieb Christoph Bumiller:
> On 11.03.2010 18:42, Uwe Bugla wrote:
> > Hi,
> >
> > I use two nv34 cards and I would like to test / try out / use the
> > Gallium driver without drawbacks.
> >
> >   
> Note that you said "use", and not "own", which is a little
> biased towards "they're plugged into the same MB".
> 
> > Unfortunately this has not been working since I decided to install /
> > compile nouveau drivers.
> >
> >   
> This is kind of a pre-requisite to be able to try the gallium
> drivers ... well, you can run a simulation in your head, but,
> that would be rather tedious.
> 
> > My system is Debian Squeeze, my kernel is 2.6.34-rc1.
> >
> > The problem is:
> >
> > Every time I load nouveau_dri.so into RAM existing applications are
> > broken / unusable (Example: gnome-games).
> >
> >   
> Loading stuff into RAM by itself shouldn't cause any problems
> if that RAM isn't used by something else, but, I'll just interpret
> this as best I can:
> AIGLX is loading it from .../lib/dri/, i.e. you installed it globally -
> not the safest way to try, because now any app using OpenGL
> may use the hw through indirect rendering.
> (indirect meaning app -> libGL -> Xorg -> nouveau_dri, instead
> of app -> libGL -> nouveau_dri)
> 
> > It does not matter if I overwrite existing versions of libglut*,
> > libGLw*, libGLU*, libGL*, libEGL* or not - that does not make any
> > difference.
> > The center of the problem is nouveau_dri.so and nothing else.
> >
> >   
> Sure, libGL etc. don't directly control the hardware, they
> hook into the dri driver (nouveau_dri.so) to do that.
> 
> > Could it please be possible to modify this driver file so that it does
> > NOT continue to break existing applications??
> >
> >   
> It will break existing applications if existing applications make
> use of it and it is itself broken.
> So, either don't let them use it, or fix it. We're working on that.
> 
> Consider yourself lucky that you got an answer at all. Normally,
> at this time, we don't care about the process of people trying the
> gallium driver without knowing exactly (well, to a certain degree
> at least) what they're doing.
> 
> Half-expecting to have my message dissected now,
> 
> Christoph
> > Would be a pleasure!
> >
> > Cheers
> >
> > Uwe

Christoph,

Thanks for the explanation of "indirect rendering".

"Consider yourself lucky that you got an answer at all."
Please avoid sentences like that one, as this bum style really sucks!

In addition to my proposal of changing the intro of the Gallium HOWTO
I would propose to establish an (incomplete) list of apps known to work
with the Gallium driver. So one can easily find out the gaps and at
least try to fill them by testing.

Reason / Conclusion:
Developers of whatever kind of software aren't omnicient gods.
They need feedback, cause without that feedback they are lost.
Whenever Gallium and nouveau will be stable or "finished" they will not
be the result of "Stay-away-from-it" slogans by some profile-neurotic
stupid, arrogant and asocial would-like-to's. They will be instead
products of a social community work of many many different people.

Cheers

Uwe