Early boot messages on UEFI systems with grub

For quite a while I had the problem on UEFI systems that after grub had loaded the kernel there were no boot messages shown until KMS kicked in and switched to the final framebuffer driver. Finally slashbeast, a fellow Gentoo dev, told me the correct kernel cmdline to make early boot messages appear:
CODE:
earlycon=efifb

As prerequisite, the kernel needs to have CONFIG_FB_EFI compiled in and CONFIG_X86_SYSFB disabled.