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

[Maarten Lankhorst]

Hey,

Op 12-06-12 05:52, Eric Appleman schreef:
> 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.
Once the api has been worked out, it will be really trivial[2] to make prime
work with SNA, so I wouldn't worry about it. I've been helping airlied out
as well on the nouveau side, but some bugs related to sharing tiled buffers
haven't been worked out yet.

> 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
>
[2] For small amounts of trivial, it won't be that much work at least.