[Mesa-dev] Change in Mesa triggers bug in Firefox Nightly with WebRender on old AMD hardware

[Ilia Mirkin]

On Tue, Apr 30, 2019 at 10:42 AM Ilia Mirkin <imirkin at alum.mit.edu> wrote:
>
> On Tue, Apr 30, 2019 at 2:48 AM Dave Airlie <airlied at gmail.com> wrote:
> >
> > On Tue, 30 Apr 2019 at 08:47, Dave Airlie <airlied at gmail.com> wrote:
> > >
> > > On Tue, 30 Apr 2019 at 08:42, Ilia Mirkin <imirkin at alum.mit.edu> wrote:
> > > >
> > > > Thing is, I think that would not be enough - with the "recent" (like
> > > > past 2 years) CSO/state change detection changes, I think that you can
> > > > end up with no sampler set for a buffer view. Perhaps someone with the
> > > > hw can investigate what goes wrong?
> > >
> > > I'm trying to get a live r600/700 machine, I plugged in my rv635 and
> > > rv740 gpus, and they both seemed toast, I've got an rv635 laptop I'll
> > > try and get up to date.
> >
> > I've found a working rv770 and reproduced it here. This isn't an
> > indication I'll get to fix it soon, but I will try.
>
> When I was debugging this issue on nouveau (and trying to nail down
> specifically what didn't work and what was required to make it work),
> I found that using a gallium test to debug this made the issues at
> hand quite obvious, and I didn't have to worry about how to force the
> st to assign mappings here or there for views or samplers. I'm not
> sure if I still have those left over, but I'll have a look tonight.
> They're also not terribly difficult to write.

In case it's helpful:
https://people.freedesktop.org/~imirkin/tbo-tex.c which fits together
with the other gallium/tests/trivial ones.

I think there were associated Makefile.am changes, but with the
removal of autoconf, I probably lost the local changes.

In its current form, it doesn't create a sampler, but you can see how
trivial/quad-tex.c does it if you want to play around with having
samplers around. You might also have to use PIPE_FORMAT_R8G8B8A8_UNORM
instead of the BGRA variant for the view's format (iirc r600 has some
limitations around swizzling and buffer textures).

  -ilia