[Mesa-dev] Q: to which software renderers should we contribute to help virgl conformance testing

[Gert Wollny]

Dear all, 

we are looking into doing a CI for virglrenderer that also runs a
subset of the GLES dEQP, and in order to be able to run this also in
gitlab.fd.o we were looking into the available gallium software
renderers. Inital tests by just running the dEQP-GLES2 were quite
successful in the sense that the exection time is not too long (a full
run on the GL and GLES host with llvmpipe takes about 10 min [1]). 

Now to extend on that work the focus is turning to which software
renderer has the most features, the least failing tests, and is
actively developed. 

Simply looking at the commit stats it seems that the developement of
softpipe and llvmpipe is mostly stalled, swr, on the other had has seen
quite some development, but mostly regarding performance, and given the
FAQ [2] the focus is on a very specific application space and not so
much on getting more features in.

When checking for conformance of virglrenderer we need a host driver
that is conformant itself, and we are willing to contribute here, but
it seems to make most sense to focus this work on just one driver. To
make sensible choice there are some open questions:

Are there plans to get swr and/or llvmpipe to support gles 3.1, or
carry any of the drivers even further, maybe GLES 3.2 and desktop 4.x?


Is there any specific interest to fix all failures that occur when
running gles dEQP? In this bug report [3] Roland pointed out that
"there is no goal as such to pass dEQP, although patches are welcome",
any opinion for the other drivers? (for swr beyond what is written in
the FAQ). 

As pointed out in the FAQ, swr is very Intel specific, are there plans
not layed out in the FAQ to support other, non-x86 hardware?

many thanks 
Gert

[1] https://gitlab.freedesktop.org/gerddie/virglrenderer/pipelines
[2] https://gallium.readthedocs.io/en/latest/drivers/openswr/faq.html#w
hat-s-the-conformance
[3] https://bugs.freedesktop.org/show_bug.cgi?id=94957