[Mesa-dev] Radeon DRI1 removal

[Alex Deucher]

On Thu, Oct 20, 2011 at 12:01 PM, Alex Deucher <alexdeucher at gmail.com> wrote:
> On Wed, Oct 19, 2011 at 8:50 PM, Eric Anholt <eric at anholt.net> wrote:
>> For the MapRenderbuffer() code (See
>> http://cgit.freedesktop.org/~anholt/mesa/log/?h=rbmap for the current
>> work, which has glReadPixels() converted so far and tested on gen6 with
>> only one regression in the tip commit), I need to be able to provide a
>> linear mapping of arbitrary renderbuffers.  Radeon's legacy DRI1 support
>> gets in the way of that -- I need to use the blitter to a temporary to
>> do untiling (which means holding the hw lock across map/unmap cycles,
>> and thus refcounting the lock), and I need to do clipping on read and
>> write.
>>
>> I think it would be much better to just ditch DRI1 at this point, since
>> KMS and DRI2 are quite well established, and are relied on by shipping
>> desktop environments.
>>
>> Code to do so is at
>> http://cgit.freedesktop.org/~anholt/mesa/log/?h=radeon-kill-dri1 which
>> is tested on r300 only currently.  No piglit regressions there, though I
>> do note that copyteximage is unreliable both before and after (rendering
>> always looks good to my eyes, but readback apparently gets junk).
>>
>> So, Radeon maintainers, what do you think?  And, does anyone else want
>> to test it on the other drivers?  I caught two bugs in my r300 testing
>> (one too many lines cut in one r300 commit, and I had also removed the
>> texsubimage code in an unrelated-to-the-series commit, but it regressed
>> s3tc-texsubimage so I backed it out).
>
> I don't see AMD doing any more work on DRI1.  The cleanup would be
> nice, but it would also mean dropping support for *BSD.  OTOH, these
> drivers aren't likely to see any more changes feature-wise so sticking
> with mesa 7.11 would work.  Also, are there are any Linux distros that
> care about DRI1 anymore?  If so, speak now.  Also, as Michel said, if
> we drop DRI1 support, we might as well drop r300c and r600c altogether
> in favor of the gallium variants.

If we dropped DRI1 support in radeon, is there anything else left in
mesa that uses DRI1?

Alex