Systems and methods for hot plug gpu power control

Abstract

Systems and methods include an electronic device having multiple GPUs and a GPU power control process that controls switching between a first GPU and a second GPU, such as a high performance GPU. The electronic device uses the first GPU when an external device is coupled to an adapter connected to the electronic device.

What is claimed is: 
     
         1 . A method, comprising:
 asserting hot plug detection when an active adapter is connected;   determining, using the asserted hot plug detection, whether an external display is connected;   if the external display is connected to the active adapter, using a first graphics processing unit (GPU) of a plurality of GPUs; and   if the external display is not connected to the active adapter, using a second GPU of the plurality of GPUs.   
     
     
         2 . The method of  claim 1 , comprising receiving a hot plug detect pulse indicative of a connection of an external display to the active adapter when the external display is connected to the active adapter. 
     
     
         3 . The method of  claim 2 , comprising activating the first GPU to provide output to the external display and to an internal display if the first GPU is not active when the external display is connected to the active adapter. 
     
     
         4 . The method of  claim 1 , comprising detecting a disconnection of the external display when the active adapter is disconnected. 
     
     
         5 . The method of  claim 4 , comprising deactivating the first GPU and activating a second GPU of the plurality of GPUs when the external display is disconnected. 
     
     
         6 . The method of  claim 5 , wherein the first GPU has greater graphics processing power than a second GPU. 
     
     
         7 . The method of  claim 4 , comprising deasserting hot plug detection after disconnection of the active adapter. 
     
     
         8 . The method of  claim 4 , comprising using the second GPU to provide output to the internal display. 
     
     
         9 . The method of  claim 1 , comprising receiving a hot plug detect pulse based on disconnection of the external display. 
     
     
         10 . The method of  claim 1 , wherein detecting disconnection of the external display from the electronic device comprises reading a register to receive an indication of the disconnection of the external display. 
     
     
         11 . A system, comprising:
 an electronic device comprising:
 a processor; 
 a first graphic processing unit (GPU); 
 a second GPU; 
 a tangible, non-transitory, computer-readable medium storing instructions configured to cause the processor to:
 detect connection of an active adapter to the electronic device; 
 assert hot plug detection upon connection of the active adapter; 
 detecting, using the asserted hot plug detection, whether an external display is connected to the active adapter; 
 upon detection of a connection of the display, switching to a first graphics processing unit (GPU) from a second GPU to process graphics to be displayed; and 
 upon detection of a disconnection of the display, switching to the second GPU from the first GPU to process graphics to be displayed. 
 
   
     
     
         12 . The system of  claim 11 , wherein the electronic device comprises an internal display. 
     
     
         13 . The system of  claim 12 , wherein the instructions are configured to cause the processor to use the first GPU to provide output to both the external display and the internal display if the external display is connected. 
     
     
         14 . One or more tangible non-transitory, computer-readable media storing instructions configured to cause a processor to:
 assert hot plug detection upon connection of an active adapter;   using the asserted hot plug detection, determine whether an external display is connected to the active adapter;   if the external display is connected to the active adapter, using a first graphics processing unit (GPU) of a plurality of GPUs; and   if the external display is not connected to the active adapter, using a second GPU of the plurality of GPUs.   
     
     
         15 . The one or more tangible non-transitory, computer-readable media of  claim 14 , wherein the first GPU comprises more processing power than the second GPU. 
     
     
         16 . The one or more tangible non-transitory, computer-readable media of  claim 15 , wherein the first GPU uses more power than the second GPU. 
     
     
         17 . The one or more tangible non-transitory, computer-readable media of  claim 14 , wherein the instructions are configured to cause the processor to receive an indication of disconnection of the external display from the active adapter. 
     
     
         18 . The one or more tangible non-transitory, computer-readable media of  claim 17 , wherein the instructions are configured to cause the processor to deactivate the first GPU in response to the disconnection of the external display. 
     
     
         19 . The one or more tangible non-transitory, computer-readable media of  claim 14 , wherein the instructions are configured to cause the processor to use the second GPU to output video to the first display regardless of the connection of the active adapter. 
     
     
         20 . The one or more tangible non-transitory, computer-readable media of  claim 14 , wherein the instructions are configured to cause the processor to use the first GPU to provide output to the external display and to use the second GPU to provide output to the internal display if the external display is connected.