the problem with this regression to older firmware is that while the kernel boots, none of the 3D functionality inherent in the new drivers is functional. I can regress to an older kernel with the newer firmware 20170622 https://git.kernel.org/?p=linux/kernel/git/firmware/linux-firmware.git and the system boots, however with zero 3d support. confirming this bug still exists in 4.12.0 through 4.12.14 as of today.