Systems and methods for reducing latency and power consumption in a peripheral component interconnect express (pcie) system

Abstract

A Peripheral Component Interconnect Express (PCIe) system and method achieve reduced power consumption and latency. When the link transitions from an active functional state in which the link has a first configuration of N active lanes to a power-saving state, the number of active lanes is collapsed such that M of the N lanes are maintained in an active power-saving state and P of the N lanes are maintained in an electrically idle state, where M, N and P are positive integers and N>P>M. The reduction in lane width reduces power consumption. Bit values specifying the current link configuration can be saved in a control register and read and compared to bit values contained in a link control register before transitioning back to the active functional state. If the bit values match, the active functional state is resumed directly from the recovery state, thereby reducing latency.