Yes, and they've been around for a while. If you're old enough, you might remember the name "PowerVR".
Today, they mostly license GPU designs to SoC vendors. You'll find their designs in e.g. Android phones.
Notably, JH7110 (RISC-V SoC used in VisionFive2 and Star64) uses one of their recent GPUs.
Currently they do not support the specific variant used in JH7110, but they seem to both be variants of the same architecture.
JH7110 has the BXE-4-32MC1[0], whereas the driver currently supports the BXS-4-64-MC1[1].
No idea about compute, and AIUI openCL suport in mesa3d is still a disaster for all drivers.
0. https://www.imaginationtech.com/product/img-bxe-4-32-mc1/
1. https://www.imaginationtech.com/product/img-bxs-4-64-mc1/
Besides the JH7110 there's TH1520 and it's using the BXM-4-64-MC1, also not supported, but 2X the speed of BXE-4-64-MC1 if I understand it correctly.