[ubuntu-x] 1st round of Prime is on track to ship as a part of Quantal's graphics stack?

[Eric Appleman]

On 06/11/2012 09:41 PM, Bryce Harrington wrote:
> On Mon, Jun 11, 2012 at 05:30:39PM -0400, Eric Appleman wrote:
>> Per my understanding the decision of X server 1.12 vs 1.13 is undecided.
>> Assuming 1.13 could ship (meaning AMD does a special Catalyst like they
>> always do), DRI2 offloading without dynamic switching could be supported
>> for Intel UXA + Nouveau setups.
>>
>> In terms of exposure to the user, David Airlied put forth the following
>> comment [1][2].
>>
>> "the first implementation will just involve setting an env var, like
>> DRI_PRIME=1, then I'm hopefully going to add a gnome-shell extension to
>> make the same possible from a launcher or some sort.
>>
>> After that people can do what they like ;-)"
>>
>> X server 1.14 should have dynamic switching and my assumption is that
>> 13.04 will ship with it, but the opportunity exists to have some level
>> of hybrid graphics support for 12.10.
>>
>> However, the plans to ship Intel SNA kinda interferes with this since
>> Prime is UXA-only at the moment [3]. I have no idea if SNA Prime is even
>> feasible for 13.04.
>>
>> If SNA is not deemed ready for 12.10 due to bugs or a perceived
>> immaturity, UXA Prime will ship (assuming 1.13).
> 
> Thanks for the head's up on UXA Prime.
> 
> Offhand, both SNA and Prime sound like they're promising higher
> performance for users.  SNA presumably would benefit a wider scope of
> users since it applies to all hardware, however Prime would enable
> hardware that currently is bordering on unusable, even if that
> represents a smaller scope in the market.  Conversely, the regression
> risk on SNA is a lot higher, so I still think it's the most fruitful
> thing to test near-term.
> 
> But, a large part of why we're going to try enabling SNA now is to help
> bring issues - like this one - to light.  I'm hoping if we do end up not
> going forward with SNA this cycle, that at least it'll give us some
> tangible feedback for upstream, so we can have a better chance in the
> future.
> 
> Bryce
> 


Intel UXA + Nouveau EXA prime also depends on the rest of the drvscreen
code landing in stable releases of each DDX. The basic framework started
landing a few days ago in master branches. Current trajectory has
everything on track.

I personally think SNA is ready, but the daily commits make it hard to
track what changes over the course of a week. It was only a few days ago
that a bug affecting rendering of Ambiance-themed elements was fixed[1].
Everything has been stable since, but it was pretty bad and Ubuntu specific.

- Eric

[1] https://bugs.freedesktop.org/show_bug.cgi?id=48630