In an embodiment, a south chip comprises a first virtual bridge connected to a shared egress port and a second virtual bridge also connected to the shared egress port. The first virtual bridge receives a first secondary bus identifier, a first subordinate bus identifier, and a first MMIO bus address range from a first north chip. The second virtual bridge receives a second secondary bus identifier, a second subordinate bus identifier, and a second MMIO bus address range from a second north chip. The first virtual bridge stores the first secondary bus identifier, the first subordinate bus identifier, and the first MMIO bus address range. The second virtual bridge stores the second secondary bus identifier, the second subordinate bus identifier, and the second MMIO bus address range. The first north chip and the second north chip are connected to the south chip via respective first and second point-to-point connections.