PXE_VOID Block(UINT64 unq_id, UINT32 enable);
PXE_VOID Delay(UINT64 UnqId, UINTN microseconds);
PXE_VOID Map_Mem(UINT64 unq_id, UINT64 virtual_addr, UINT32 size, UINT32 Direction, UINT64 mapped_addr);
PXE_VOID Mem_IO(UINT64 UnqId, UINT8 read_write, UINT8 len, UINT64 port, UINT64 buf_addr);
PXE_VOID Sync_Mem(UINT64 unq_id, UINT64 virtual, UINT32 size, UINT32 Direction, UINT64 mapped_addr);
PXE_VOID UnMap_Mem(UINT64 unq_id, UINT64 virtual_addr, UINT32 size, UINT32 Direction, UINT64 mapped_addr);
protocol driver can provide anything for this Unique_ID, UNDI remembers that as just a 64bit value assocaited to the interface specified by the ifnum and gives it back as a parameter to all the call-back routines when calling for that interface!
PXE_VOID Virt2Phys(UINT64 UnqId, UINT64 virtual, UINT64 physical_ptr);