[Rydberg, Johan] in other words; would it be possible to write a firmware 
(not based on any of Intel's code) that complies to the EFI specifiction, 
and release it under GPL?

[Doran, Mark] We believe the answer to this is "yes!"  I understand
there are OS loader implementations of EFI interface consuming code
already released with GPL terms and from the point of view of the spec
code that produces interfaces to match the definitions in the spec is no
different than code that consumes said interfaces.