debian does not boot after dist-upgrade to jessie

[gasha <gasha@pie-dabas.net>]

Hi all,
did not have enough time to investigate (have to spend time in cold server
room) yet.
But 3.11 kernel did not boot after dist-upgrade
Hardware = rx4640
kernel booted pretty long (300+ seconds, from timestamps), complained a
lot about ACPI, but latest error was UUID= root device not found, dropped
to grub/initrd prompt.

Any ideas, how to get it back? any success with 3.11 ?
I have limited knowledge about EFI (adding another boot entry with old
kernel) ?

Gatis