Method and apparatus for power throttling of highspeed multi-lane serial links

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.

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.