US 9,813,998 B2
Techniques for entering a low-power link state
Shaun M. Conrad, Cornelius, OR (US); Robert J. Safranek, Portland, OR (US); and Selim Bilgin, Hillsboro, OR (US)
Assigned to Intel Corporation, Santa Clara, CA (US)
Filed by Shaun M. Conrad, Cornelius, OR (US); Robert J. Safranek, Portland, OR (US); and Selim Bilgin, Hillsboro, OR (US)
Filed on Mar. 7, 2011, as Appl. No. 13/42,104.
Application 13/042,104 is a continuation of application No. 12/685,874, filed on Jan. 12, 2010, granted, now 7,925,954.
Application 12/685,874 is a continuation of application No. 11/480,065, filed on Jun. 29, 2006, granted, now 7,716,536.
Prior Publication US 2011/0161702 A1, Jun. 30, 2011
This patent is subject to a terminal disclaimer.
Int. Cl. H04L 1/18 (2006.01); H04W 52/28 (2009.01); H04L 1/00 (2006.01); H04W 52/48 (2009.01)
CPC H04W 52/28 (2013.01) [H04L 1/0045 (2013.01); H04L 1/0057 (2013.01); H04L 1/0061 (2013.01); H04W 52/287 (2013.01); H04W 52/48 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An apparatus comprising:
a physical point-to-point link within an electronic system having a cache-coherent, link-based interconnect fabric;
a first component within the electronic system coupled with a first end of the point-to-point link, the first component to transmit a request over the point-to-point link to initiate transition of the point-to-point link from an active state to a low power state, the first component to operate as a master device in a power control negotiation, wherein the point-to-point link is to be incapable of transmitting packets during the low power state; and
a second component within the electronic system coupled with a second end of the point-to-point link, the second component, in response to the request, to selectively allow or disallow the transition of the point-to-point link from the active state to the low power state, wherein the second component sends negative acknowledge (NACK) message to disallow the transition of the point-to-point link from the active state to the low power state, and further wherein the first component maintains the point-to-point link in the active state in response to the NACK message, the second component to operate as a slave device in the power control negotiation, wherein no pending transactions or subsequent transactions are to occur within an upcoming period of time.