https://bugs.freedesktop.org/show_bug.cgi?id=66942
--- Comment #6 from Alexandre Demers alexandre.f.demers@gmail.com --- (In reply to comment #5)
Sounds like you may be waiting for the firmware loader to timeout. Make sure you have the new cayman smc ucode installed: http://people.freedesktop.org/~agd5f/radeon_ucode/CAYMAN_smc.bin
Yes, it was missing. I'll test kernel 3.11-rc1 with it and with bug 66551's patch.