OPTIMIZED ENVIRONMENT FOR VIRTUALIZING PHYSICAL SUBSUBSYSTEMS INDEPENDENT OF THE OPERATING SYSTEM

A computing system having a processor employs an accelerated virtual subsystem architecture which may reside in either the processor or chipset logic circuitry disposed on the motherboard. The accelerated virtualization process employs at least one phantom read register that provides logical status information in response to an I/O read operation or operations--avoiding engagement of the system management mode as fulfillment of the virtualization process. The at least one phantom read register is updated by the virtualization process and supplies the expected response to an application/driver program running on the processor responsive to the execution of an I/O read operation without invocation of an SMI. Preferably, at least one latch is further provided to buffer writes of indexes of index/data write pairs to further avoid engagement of the system management mode as fulfillment for the virtualization process. When the data write of the index/data pair write occurs, application/driver software retrieves the buffered index for use in the virtualization process to virtualize the appropriate behavior. Alternatively, multiple index/data write pairs may be gathered and acted on when a predetermined index value is recognized.