Fails to lauch X on laptop with Ryzen 7 4700U

We are working with new laptops that have the Ryzen 7 4700U.

It fails to launch X so I can only access via the virtual terminal. I tried with the latest mainline kernel and kernel from https://cgit.freedesktop.org/~agd5f/linux but no luck. I also boot the kernel with parameter amdgpu.exp_hw_support=1, but the system freezes after loading amdgpu and I can't even switch to the virtual terminal.

I post the bug description and related information on https://gitlab.freedesktop.org/drm/amd/issues/1031.

Please kindly advise what I should do next.

Thanks Chris