Maybe you could try to use the pdaxrom builder to build the toochain under free bsd?
I'am not sure if the builder requires any linux specific tool but I would give it a try if I was a freebsd user

Instructions are available here:
http://www.oesf.org/index.php?title=PdaXrom:_pdaXrom-builderIf you manage to build the toolchain and don't want to build the whole package libraries, you could probably be able to replace the linux binaries of the linux-sdk.