https://bugs.freedesktop.org/show_bug.cgi?id=78453
--- Comment #69 from Michel Dänzer michel@daenzer.net --- First of all, let me remind both of you to make sure si_get_backend_mask() gets the information from the kernel, and to use my patch which disables tiling as much as possible for now.
Also, might be worth testing with R600_DEBUG=nodma for now, to prevent the userspace code from using the asynchronous DMA engine.
(In reply to comment #64)
- egltri_screen from mesa-demos works, outputs a coloured triangle on grey
background for 5s (with 3 monitors attached)
That's all it's supposed to do, FWIW. :)
(In reply to comment #65)
Sometimes it even works again after a few invocations with garbage, but the triangle is not centered then, but offset to the left or right. The garbage also looks deterministic (always identical for the third and fourth invocation after a restart).
Still, I'd assume in those cases it doesn't actually render anything but just displays leftovers from previous runs.
To differentiate that, I built a second copy of egltri_screen with all rendering commands except for glClear() disabled (and a glClearColor() call added for a distinctive clear colour). By running both copies alternatively, I could be pretty sure whether what I'm seeing was rendered by the current run or just a leftover.
(In reply to comment #68)
I can't get EGL to work with newest mesa, with the following messages when trying to run egltri_screen: # EGL_LOG_LEVEL="debug" EGL_PLATFORM="drm" ./egltri_screen
Does it work if you add EGL_DRIVER=egl_dri2 ?
I attached a dmesg with patch 99839 from Christian König but NOT patch 99594 from Alex Deucher, with newest mesa, where I did a "Xorg -retro" start and then glxinfo (which garbles the screen).
I'm afraid it's still too early to test in X. Even without -retro, the GPU is probably used for some operations via glamor, e.g. for the cursor image.