1. An Ethernet controller which processes packets received from a plurality of root complexes via a serial load/store fabric, the Ethernet controller comprising: a bus interface coupled to the serial load/store fabric, said bus interface associating each of the packets with their root complex; and control register logic, having a plurality of control registers, wherein each of said plurality of control registers is selectable to service at least one of the root complexes based on the association of the packets with their originating root complex.