misc fixes for VC4

[Pekka Paalanen]

On Sat, 3 Jan 2015 16:10:21 -0500
Rob Clark <robdclark at gmail.com> wrote:

> On Sat, Jan 3, 2015 at 12:35 PM, Keith Packard <keithp at keithp.com> wrote:
> > Rob Clark <robdclark at gmail.com> writes:
> >
> >> hmm, what minimum gl and gles version do we need to expose instanced
> >> drawing?   Or any other useful extensions that glamor could use?  Not
> >> sure if that would make a difference between gl vs gles?
> >
> > We use instanced drawing on anything with GLSL version 1.30 or later.
> >
> > As for extensions, we check for:
> >
> > GL_EXT_texture_format_BGRA8888
> > GL_KHR_debug
> > GL_MESA_pack_invert
> > GL_EXT_framebuffer_blit
> > GL_ARB_map_buffer_range
> > GL_ARB_buffer_storage
> > GL_NV_texture_barrier
> > GL_OES_EGL_image
> >
> >> At any rate, we still have the problem that glamor will see that the
> >> driver supports both gles and gl, and would have to somehow choose
> >> which paths to use.. although I guess we could just pick based on
> >> vendor name for freedreno/vc4/etc..
> >
> > I think we'd rather use real GL on devices that have a real GL driver;
> > however, we need to avoid fallbacks in the driver, which means creating
> > some way for the driver to tell glamor what paths to avoid...
> 
> I guess to start with, we could use hard-coded table keyed by vendor
> name, perhaps.. although that is a bit lame
> 
> maybe inventing a glIsEmulatedMESA(GLenum) type thing would be a good idea?

Hi,

I hope you don't mind me jumping on a tangent here, but we have this
report for Xwayland with Glamor:
https://bugs.freedesktop.org/show_bug.cgi?id=86815

It's a case of an eeePC being awfully slow when Glamor is used
(i915_dri.so) and I have no idea if Glamor even makes sense on such
hardware. Without Glamor performance is reported to be ok.

While you are pondering how to choose the proper path in Glamor,
maybe you could take also this case into account?


Thanks,
pq