Opengl driver on non pi4 models?

retropieuser555

Pi Model or other hardware: pi zero w 2
Power Supply used: DC usb cable
RetroPie Version Used 4.7.19
Built From: RetroPie website nightly
USB Devices connected:
Controller used:
Error messages received:
Verbose log (if relevant):
Emulator:

So not sure if this was ever resolved but I know with the pi4 you can use the vc4-fkms-3d or the vc4-kms-3d in boot/config.txt. done some hunting online and notice if you try and use fkms or Kms on earlier models it gives you an "emulationstation service in use" error when booting and leaves you at the command line.

Is this something that is expected? Just wondering if there was ever a fix for pi 3 (and therefore likely to work on a pi0 w 2)

mitu

@retropieuser555 said in Opengl driver on non pi4 models?:

Is this something that is expected?

Yes

Just wondering if there was ever a fix for pi 3 (and therefore likely to work on a pi0 w 2)

There's no 'fix', the OpenGL driver is not supported or configured on the Pi3 or earlier models. It should work, but you'll need to re-install all packages from source after it's enabled, since we don't provide binaries for this configuration and switching the GPU drivers needs a different set of options applied to packages' compilation.

My guess is that you'll need to enable the vc4-kms-3d overlay, but I think it can be done also from raspi-config. Note that enabling it will disable some of the functionality present - like the splashscreen, omxplayer , display configuration via config.txt, kodi, etc.

retropieuser555

@mitu I might give it a shot on another SD card but with the retroflag gpi the display config inside the boot/config.txt is pretty much necessary to output the correct display. Even if I compiled everything from source anew, the splash screen and config.txt displays settings still wouldn't work? Or you're saying without recompiling those features won't work?

mitu

@retropieuser555 said in Opengl driver on non pi4 models?:

Even if I compiled everything from source anew, the splash screen and config.txt displays settings still wouldn't work?

Yes.
The config.txt video options are no longer applied to the GPU/video driver, since that was done by the RPI firmware, using the KMS kernel driver means everything is driven by the Linux kernel and not the firmware.

The splashscreen is using the dispmanx API to overlay the image and omxplayer to play the video, but with the KMS overlay there is no dispmanx API available, so everything that depends on it will not function.
Re-compiling the packages will give you a functional RetroArch, EmulationStation, SDL2 and - most of the - standalone emulators. Some emulators will not work, since they depend on the old/legacy GPU drivers (standalone pcsx-rearmed or even mupen64plus for instance). Of course, using this configuration some things might not work, since is not a fully tested setup with RetroPie, YMMV.

retropieuser555

@mitu I see, it might be a dead end then, as retroflag gpi requires edits to the display settings to output (as it's a DPI/LCD screen connected by the GPIO). So it might be a total deadend.

I might mess with it for fun though over Xmas break and report back