QUALCOMM Incorporated
System power management for peripheral component interconnect express (PCIE)-based devices

Abstract:

Systems and methods for power management for Peripheral Component Interconnect express (PCIE) devices allow PCIE termini to enter advanced low-power states while a PCIE link is idle. These advanced low-power states may include scaling a clock frequency up through a complete shutdown of power rails and clocks within the PCIE terminus. Additionally, use of a wakeup signal such as a clock request (CLKREQ or CLKREQ #) signal may allow the terminus to wake relatively quickly and resume operation so as to avoid degradation of the user experience or loss of data.