Active state power management (ASPM) to reduce power consumption by PCI express components

摘要

Methods and apparatus relating to Active State Power Management (ASPM) to reduce power consumption by PCI express components are described. In one embodiment, a special packet with embedded information triggers entry into a lower power consumption state. The embedded information may include flow control credit information outstanding between two agents and the target power consumption state. Other embodiments are also disclosed and claimed.

主权项

1. An apparatus comprising:
a first agent to comprise controller logic to cause a link to enter a low power consumption state in response to a Data Link Layer Packet (DLLP), wherein the DLLP is to indicate a request to enter the low power consumption state and wherein the DLLP is to comprise flow control credit information, shared amongst the first agent and the second agent, wherein the first agent is to comprise a downstream component and the second agent is to comprise an upstream component, wherein the link is to couple the first agent and the second agent, wherein the DLLP is to cause embedding of the flow control credit information in response to transmission of an acknowledgement signal from the upstream component, wherein the upstream component is to ensure all credit limits have been transmitted before transmission of the acknowledgement signal, wherein the link is to enter the low power consumption state in response to transmission of the acknowledgement signal.