[Nouveau] [PATCH] Add Option "DRI3" to allow to disable DRI3 under EXA.

[Dave Airlie]

>>>
>>> We can disable it by default on exa - intel and amd/radeon drivers also
>>> disable by default. However, on gpus >= maxwell only glamor accel is
>>> supported and glamor on nouveau is either dri3/present or no hw accel at
>>> all
>>> afaics.
>>
>>
>> You probably saw my patches to just remove glamor from nouveau :) That
>> integration doesn't support DRI2, which in turn means no core contexts
>> (due to lack of GLX_ARB_create_context_profile), and a slew of other
>> issues. Seemed easier to just tell people to go use modesetting, which
>> gets all of these things right(er).
>>
>
> Hm, a total removal would at least make me and my users rather unhappy atm.,
> as without glamor no hw accel at all on >= maxwell. modesetting and nouveau
> are not on par feature-wise atm. E.g., modesetting as of the next xorg 1.18
> server only provides pageflipping via dri3/present and without pageflipping
> it is game over for many of my use cases on nouveau-kms. Also modesetting
> currently completely lacks ZaphodHeads support. Without ZaphodHeads i can't
> have a page-flipped fullscreen window on one subset of outputs and a regular
> desktop on another subset, something that is needed for
> neuroscience/medical/vr applications.

So what would you want in modesetting to be on par?

DRI2 pageflipping?
zaphod heads?

anything else? I would like for F23 to ship a modesetting which I can
replace intel/nouveau/ati with.

Dave.