There is a fork of Mesa with some support for the onboard GPU (Immortals G720), but it's not upstream yet and might not be for a while. Some people on the forums have installed various discrete GPUs, which would obviously work (modulo bugs.)

There is also an open source driver for the NPU somewhere (Zhouyi NPU) and some documentation, but nothing in an upstream kernel yet. https://zhouyi-npu-tutorial.readthedocs.io/en/latest/0_radxa...