I need to cross-compile a PowerPC Linux kernel on an x86 laptop. I've found instructions on how to compile (not cross-compile) the Linux kernel at this website. Further, there is a post to a mailing list here which shows how to cros-compile the kernel. The mailing list post mentions a ccontrol file, but I have no clue what that is. Luckily I've found this blog post, which seems to be more accurate.