# US 9,519,331 B2 · Method and apparatus for power throttling of highspeed multi-lane serial links > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,519,331 B2 - Document ID: US9519331B2 - Status: Granted - Kind: B2 - Application number: 14/051,612 - Filed: 2013-10-11 - Published: 2014-02-06 - Granted: 2016-12-13 - Earliest claimed: 2007-10-22 - Assignees: Dell Products L.P. - Applicants: Mukund Khatri; Lee Zaretsky - Inventors: Mukund Khatri; Lee Zaretsky - Web page: https://patentgrep.com/patent/US9519331B2 ## CPC - G06F 1/3253: {Power saving in bus} - G06F 1/3215: Monitoring of peripheral devices - Y02D 10/00: Energy efficient computing, e.g. low power processors, power management or thermal management - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - Y02D: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE ## Abstract A method for managing the power consumption of an information handling system including a multi-lane serial link having a lane setting that identifies the number of active lanes in the multi-lane serial link. The method may include determining a number of lanes required for the multi-lane serial link based on one or more I/O devices connected to the information handling system, triggering a reduction of the lane setting of the multi-lane serial link if the lane setting of the multi-lane serial link is greater than the determined number of lanes required, and automatically reducing power to the multi-lane serial link in response to the reduction of the lane setting. ## Claims ### Claim 1 A method for managing the power consumption of an information handling system comprising: determining at regularly defined intervals a number of lanes required for a multi-lane serial link, wherein the multi-lane serial link is connected to a host associated with the information handling system, wherein the regularly defined intervals are based on initialization of the host, and wherein the number of lanes required is based on: determining a number of one or more powered-on I/O devices connected to the multi-lane serial link, determining a number of one or more powered-off I/O devices connected to the multi-lane serial link, including in the number of lanes required lanes for the number of one or more powered-on I/O devices, and excluding from the number of lanes required lanes for the number of one or more powered-off I/O devices; triggering a reduction of a lane setting of the multi-lane serial link if the lane setting of the multi-lane serial link is greater than the determined number of lanes required, the lane setting based on the number of active lanes in the multi-lane serial link; triggering a reduction of the lane setting of the multi-lane serial link if a powered-on I/O device is powered-off; and automatically increasing the lane setting of the multi-lane serial link if an additional powered-on I/O device is connected to the information handling system through the multi-lane serial link. ### Claim 2 (depends on 1) The method of claim 1, further comprising reducing power to the multi-lane serial link in response to the reduction of the lane setting. ### Claim 3 (depends on 2) The method of claim 2, wherein reducing power to the multi-lane serial link includes eliminating power to unused lanes of the multi-lane serial link. ### Claim 4 (depends on 2) The method of claim 2, further comprising: triggering an increase of the lane setting of the multi-lane serial link if the lane setting of the multi-lane serial link is less than the determined number of lanes required; and increasing power to the multi-lane serial link in response to the increase of the lane setting. ### Claim 5 (depends on 1) The method of claim 1, further comprising decreasing the lane setting of the multi-lane serial link if a powered-on I/O device is removed from the information handling system through the multi-lane serial link. ### Claim 6 (depends on 1) The method of claim 1, wherein determining the number of lanes required for the multi-lane serial link is performed by a boot monitor and wherein triggering of the reduction of the lane setting of the multi-link serial link is performed by the boot monitor. ### Claim 7 (depends on 1) The method of claim 1, wherein determining the number of lanes required for the multi-lane serial link includes determining the type of the one or more powered-on I/O devices connected to the multi-lane serial link. ### Claim 8 An information handling system comprising: a host; a multi-lane serial link connecting one or more I/O devices to the host; the multi-lane serial link having a lane setting that identifies the number of active lanes in the multi-lane serial link; and a baseboard management controller associated with the host configured to: determine at regularly defined intervals a number of lanes required for the multi-lane serial link, wherein the number of lanes required is based on: determining a number of one or more powered-on I/O devices connected to the multi-lane serial link, determining a number of one or more powered-off I/O devices connected to the multi-lane serial link, including in the number of lanes required lanes for the number of one or more powered-on I/O devices, and excluding from the number of lanes required lanes for the number of one or more powered-off I/O devices; trigger a reduction of the lane setting of the multi-lane serial link if the lane setting of the multi-lane serial link is greater than the determined number of lanes required, the regularly defined intervals based on initialization of the host; trigger a reduction of the lane setting of the multi-lane serial link if a powered-on I/O device is powered-off; and automatically increase the lane setting of the multi-lane serial link if an additional powered-on I/O device is connected to the host through the multi-lane serial link. ### Claim 9 (depends on 8) The information handling system of claim 8, wherein the baseboard management controller reduces power to the multi-lane serial link in response to the reduction of the lane setting. ### Claim 10 (depends on 9) The information handling system of claim 9, wherein reducing power to the multi-lane serial link includes eliminating power to unused lanes of the multi-lane serial link. ### Claim 11 (depends on 9) The information handling system of claim 9, wherein the baseboard management controller triggers an increase of the lane setting of the multi-lane serial link if the lane setting of the multi-lane serial link is less than the determined number of lanes required and increases power to the multi-lane serial link in response to the increase of the lane setting. ### Claim 12 (depends on 8) The information handling system of claim 8, wherein the baseboard management controller decreases the lane setting of the multi-lane serial link if the number of the one or more powered-on I/O devices connected to the host through the multi-lane serial link is decreased. ### Claim 13 (depends on 8) The information handling system of claim 8, wherein the baseboard management controller determines a bandwidth requirement of the one or more powered-on I/O devices connected to the host through the multi-lane serial link based on the number of the one or more powered-on I/O devices. ### Claim 14 (depends on 8) The information handling system of claim 8, wherein the baseboard management controller determines a bandwidth requirement of the one or more powered-on I/O devices connected to the host through the multi-lane serial link based on the type of the one or more powered-on I/O devices. ### Claim 15 A computer program product comprising computer executable instructions, stored on a non-transitory tangible computer readable medium, for managing the power consumption of a multi-lane serial link having a lane setting that identifies the number of active lanes in the multi-lane serial link, the instructions comprising: instructions for determining at regularly defined intervals a number of lanes required for the multi-lane serial link, wherein the regularly defined intervals are based on initialization of the host, and wherein the number of lanes required is based on: determining a number of one or more powered-on I/O devices connected to the multi-lane serial link, determining a number of one or more powered-off I/O devices connected to the multi-lane serial link, including in the number of lanes required lanes for the number of one or more powered-on I/O devices, and excluding from the number of lanes required lanes for the number of one or more powered-off I/O devices; instructions for triggering a reduction of the lane setting of the multi-lane serial link if the lane setting of the multi-lane serial link is greater than the determined number of lanes required; instructions for triggering a reduction of the lane setting of the multi-lane serial link if a powered-on I/O device is powered-off; and instructions for automatically increasing the lane setting of the multi-lane serial link if an additional I/O device is connected to the host through the multi-lane serial link. ### Claim 16 (depends on 15) The computer program product of claim 15, further comprising instructions for reducing power to the multi-lane serial link in response to the reduction of the lane setting. ### Claim 17 (depends on 16) The computer program product of claim 16, wherein reducing power to the multi-lane serial link includes eliminating power to unused lanes of the multi-lane serial link. ### Claim 18 (depends on 15) The computer program product of claim 15, further comprising instructions for increasing power to the multi-lane serial link in response to an increase of the lane setting of the multi-lane serial link.