add support memory size above 2GB, add debug messages
add support memory size above 2GB, add debug messages

RWTH-OS/HermitCore,stlankes/HermitCore,stlankes/HermitCore,stlankes/HermitCore,RWTH-OS/HermitCore,stlankes/HermitCore,stlankes/HermitCore,stlankes/HermitCore,RWTH-OS/HermitCore,RWTH-OS/HermitCore,RWTH-OS/HermitCore,RWTH-OS/HermitCore