I have been created a build with Buildroot. Also did it everthing on this comment -> https://www.raspberrypi.org/forums/viewtopic.php?t=263418#p1614833 Did my research, and dozens of trials, and I get nothing.
My config is: Rpi4-64, QT5-Qml, Mesa v3d-vc4, opengl es 2.0
When I try to run my qt qml application on this build, I'm getting this error:
QStandardPaths: wrong permission on runtime directory /usr/bin/, 7755 instead of 7700 drmModeGetResources failed (Operation not supported) no screens available, assuming 24 -bit color Cannot create window: no screens available.
Summary : I need to run my qt5 qml application on Rpi 4 with hw accelerated.
I found the solution. I think the Rpi4 with eglfs using default card for card0, and this is not work. Need to force using card1 for eglfs.
Create a file "eglfs.json" with the following content:
export QT_QPA_EGLFS_KMS_CONFIG=/wherever/is/the/file/eglfs.json and run your qt app!
Also my qt5 qml program is not showing fonts or text on rpi4 buildroot system. Coping /usr/share/fonts/your_program_fonts worked for me.