[SOLVED] RPi 4B, Gentoo 64bit and VC4 llvmpipe problem

[g-virus]

Hello guys! It's already the 4th evening I couldn't find a proper solution to get VC4 working. I followed NeddySeagoon's article and installed Gentoo 64bit on my Pi 4B, everything is fine except bluetooth and 3d hardware acceleration (didn't test sound actually). While bluetooth is a different problem, the Gallium doesn't work as well and I can't understand what I can do more.

Shortly:

• Linux Kernel 5.6.0-rc5 version
  
• VC4 and V3D modules are compiled and loaded successfully
  
• dtoverlay=vc4-fkms-v3d
  
• /dev/dri/card0 exists (card1 too)
  
• Mesa-20 is installed
  
• USE flags egl gles1 and gles2 are set and all the packages are rebuilt respectively
  
• the Pi is connected to Full-HD monitor via HDMI
  
• glxgears -info shows llvmpipe as a renderer, but I couldn't find any fbturbo Xorg conf files
  

I can't switch opengl context to VC4 via eselect opengl how I usually do on my desktop Gentoo. Causing of that, Picom couldn't enable GLX backend and my OpenBox environment looks ugly. Please give me any ideas, thanks in advance!

[Sakaki]

Hi g-virus,

on the RPi4, you need to modify the vanilla mesa ebuild, to work correctly with v3d.

Please see my response to the issue "MESA-20.0.0 Force using llvmPipe(software rendering)" on GitHub, here.
_________________
Regards,

sakaki

[g-virus]

Hi! Sorry, I didn't read the topic a long time. I've installed Mesa-20 from genpi64 overlay with the USE flag rpi-v3d enabled, but I still have llvmpipe renderer in glxgears. Perhaps it is because of TigerVNC which I started to use instead of Xorg + x11vnc?

[Sakaki]

g-virus,

are you accessing your desktop remotely to run glxgears, or locally (just with a VNC server running)? If remote, what happens if you run locally?

Also, as a sanity check, if you run the current gentoo-on-rpi-64bit image on your system, do you get accelerated rendering successfully (hopefully, you should!)? If so, try copying the 4.19 kernel + module set from that onto your own image and booting under that kernel temporarily - any improvement?
_________________
Regards,

sakaki

[g-virus]

Yes, I'm accessing it remotely. There is the TigerVNC software on the RPi4, and there is no the regular Xserver at all, probably this is the reason why it doesn't work as expected. I will install the Xorg server to test it

[g-virus]

Sakaki,

with MESA installed from genpi64 overlay glxgears says V3D 4.2 in the GL_RENDERER line so seems like everything is ok with software and TigerVNC just can't use hardware acceleration with its own Xorg implementation or may be I can't set it up properly. Thanks a lot for you help with MESA, I'm going to close the topic, but if you have some ideas how to enable hardware acceleration in TigerVNC please let me know, thanks in advance!