I decided to apply a hack to 4.19 and see if I could get the e=
GPU to
initialize.  I noticed that this code in /drivers/gpu/drm/amd/amdgpu/atom.c

if ((jiffies_to_msecs(cjiffies) > 5000)) {
        DRM_ERROR("atombios stuck in loop for more than 5secs aborting=
\n");
        ctx->abort =3D true;
}

is where the error is being thrown, so I thought I would try giving the eGPU
more time.  I increased the 5000 value to 15000, recompiled the kernel, and
tried to attach the eGPU.  Unfortunately I received the same error, but this
time after 15 seconds of trying to initialize the GPU.  Should I increase t=
he
time even more?

I'm not sure if the issue is actually related to not having enough time, or=
 if
it's something else entirely.

I'll bump it up to 30 seconds in a final last ditch attempt.