PCI Express System Architecture

Introduction

PCI Express power management (PM) defines two major areas of support:

• PCI-Compatible Power Management. PCI Express power management is based upon hardware and software compatible with the PCI Bus Power Management Interface Specification, Revision 1.1 (also referred to as PCI-PM) and the Advanced Configuration and Power Interface Specification, Revision 2.0 (commonly known as ACPI). This support requires that all PCI Express functions include the PCI Power Management Capability registers, which permits transitions between function PM states.

• Native PCI Express Extensions. These extensions define autonomous hardware-based Link Power Management, mechanisms for waking the system, a Message transaction to report Power Management Events ...