Every stable kernel after 3.10.95-gentoo on my IBM power4+ (9114-275) fails to boot in the exact same way.
See attached boot log. In this example I tested "3.14.58" but after testing all stable versions only 3.10.95 boots.
I plan to work though the kernel versions until I hit the exact version where it no longer boots.
However from a Gentoo point of view 3.10.95 is the last stable version that boots.
Created attachment 424410 [details]
fail boot log
Attached boot log.
I no longer have access to this machine.