Controlling auxiliary power to logic devices

Abstract

A system may include multiple logic devices, a power input, and a logic controller. The power input may be configured to provide the auxiliary power to the logic devices. The logic controller may be configured to select a group of the logic devices for disabling the auxiliary power based, at least in part, on priority levels asserted by each of the logic devices, and disable the auxiliary power to the selected group of logic devices.

1 . A system comprising:
 multiple logic devices;   a power input configured to provide an auxiliary power to the logic devices; and   a logic controller configured to:
 select a group of the logic devices for disabling the auxiliary power based, at least in part, on priority levels asserted by each of the logic devices; and 
 disable the auxiliary power to the selected group of logic devices. 
   
     
     
         2 . The system of  claim 1  wherein the logic devices are configured to assert a request for auxiliary power and the priority level in response to receiving an early power down indication. 
     
     
         3 . The system of  claim 1 , wherein the auxiliary power is insufficient to provide power to all of the logic devices. 
     
     
         4 . The system of  claim 1  wherein the power input is configured to provide the auxiliary power to the logic devices in response to a main power falling below a threshold. 
     
     
         5 . The system of  claim 1  wherein:
 the power input is configured to provide the auxiliary power to the logic devices in response to a main power powering down, and 
 the logic devices are configured to assert their respective priority levels based, at least in part, on processes performed by each of the logic devices before the main power powered down. 
 
     
     
         6 . The system of  claim 1  wherein the power input is configured to switch between providing the auxiliary power to the logic devices and providing a main power to the logic devices. 
     
     
         7 . The system of  claim 1  wherein:
 the logic devices are configured to assert their priority levels to the logic controller in response to receiving an early power down indication, and 
 the power input is configured to provide the auxiliary power to the logic devices in response to a main power powering down. 
 
     
     
         8 . The system of  claim 1  wherein the logic controller is configured to:
 determine a number of the logic devices for which the auxiliary power could meet a threshold power level; and 
 select the group of the logic devices for disabling the auxiliary power based in further part on the determined number of logic devices. 
 
     
     
         9 . The system of  claim 1  wherein the logic controller is configured to:
 poll the logic devices in response to determining that the logic devices did not receive an early power down indication; and 
 enable the auxiliary power to at least one of the logic devices based on the polling. 
 
     
     
         10 . The system of  claim 1 , wherein the logic controller is configured to poll the logic devices one at a time. 
     
     
         11 . The system of  claim 1 , wherein the logic controller is configured to:
 determine a number of the logic devices for which the auxiliary power could meet a threshold power level; and   poll the logic devices in groups based on the determined number.   
     
     
         12 . The system of  claim 1 , further comprising:
 multiple memory components, each of the memory components being associated with one of the logic devices,   wherein the logic devices are configured to retrieve, upon powering on, information stored on their associated memory component.   
     
     
         13 . A logic controller comprising:
 multiple pins configured to receive requests for auxiliary power from multiple logic devices, the auxiliary power being insufficient to provide power to all of the logic devices; and   a logic circuit configured to:
 select a group of the logic devices for disabling the auxiliary power based, at least in part, on priority levels asserted by each of the logic devices; and 
 disable the auxiliary power to the selected group of logic devices. 
   
     
     
         14 . The logic controller  13  wherein the logic circuit is configured to perform the selecting and disabling in response to a computing system including the logic controller transitioning from a main power to the auxiliary power. 
     
     
         15 . The logic controller of  claim 13  wherein the logic circuit is further configured to receive the asserted priority levels from the logic devices. 
     
     
         16 . The logic controller of  claim 13  wherein the logic circuit is configured to instruct a power input to provide the auxiliary power to the logic devices in response to a main power falling below a threshold. 
     
     
         17 . The logic controller of  claim 13  wherein the logic circuit is configured to:
 determine a number of the logic devices for which the auxiliary power could meet a threshold power level; and 
 select the group of the logic devices for disabling the auxiliary power based on the asserted priority levels and the determined number of logic devices. 
 
     
     
         18 . The logic controller of  claim 13  wherein the logic circuit is configured to:
 poll the logic devices in response to determining that the logic devices did not receive an early power down indication; and 
 enable the auxiliary power to at least one of the logic devices based on the polling. 
 
     
     
         19 . A method comprising:
 in response to transitioning from main power to auxiliary power, selecting a group of logic devices which asserted highest priority requests for the auxiliary power; and   granting the auxiliary power to the selected group of logic devices.   
     
     
         20 . The method of  claim 19 , further comprising disabling the auxiliary power to logic devices that were not selected.