there is another relevant tid-bit that Edgar did not mention here - parabola's linux-libre behaves the same; so that reasonably eliminates any peculiarities of the distro - it is probably a kernel configuration issue
Edgar - you did not answer my question on the parabola forum - namely: > have you tried other kernels? - try linux-libre-vanilla and see if that works linux-libre-vanilla is configured differently than linux-libre and the others - also, what about the parabola LiveISO, does that boot? - if there is any difference, that could point to a clue (different versions, different configs)