Method for assigning addresses to input/output devices

摘要

An I/O mapping within a system memory of a computing system assigns a fixed address to each I/O device and I/O bridge in a larger address region of the system than the number of address bits of the I/O devices and/or the I/O bridges would allow. This fixed address assignment eliminates problems associated with fragmentation of I/O memory space of a conventional variable address assignment when I/O devices and/or I/O bridges are replaced on-line, i.e., hot-swapped. The I/O mapping utilizes a greater number of address bits than the address bits available from I/O devices to assign a much larger address space to each device by translating the larger number of bits address from the system to the smaller number of bits address of the I/O devices.