Re: GPU on RPI4 8G

[mlelstv%serpens.de@localhost (Michael van Elst)]

mayuresh%acm.org@localhost (Mayuresh) writes:

>I understand from [1] that GPU support works only on 32 bit kernels.
>However [2] suggests aarch64 for RPI 4. Does it mean, GPU support won't
>work on RPI 4 as yet?

We don't really support the GPU beyond using it as a dumb framebuffer
and audio device.

There is a driver to access the GPU from userland and support code
from broadcom (raspberrypi-userland package) that can talk to the
GPU. The support code is 32bit only and the package currently only
builds for 32bit. I have a modified version that builds for 64bit,
but only for simple things, not the GPU support.


>Wouldn't earmv7hf work on RPI4 and if it would, I guess it won't be able
>to utilize the 8G RAM. Please confirm.

You need 64bit addresses for the PCI bus and thus the USB ports, not just
the RAM. 32bit RpiOS supports LPAE (extended addresses) but we do not,
so for us the RPI4 is aarch64-only.