Arbitration system and method for memory responses in a hub-based memory system

Abstract

A memory hub includes a local queue that stores local memory responses, a bypass path that passes downstream memory responses, and a buffered queue coupled to the bypass path that stores downstream memory responses from the bypass path. A multiplexer is coupled to the local queue, buffered queue, and the bypass path and outputs responses from a selected one of the queues or the bypass path responsive to a control signal. Arbitration control logic is coupled to the multiplexer and the queues and develops the control signal to control the response output by the multiplexer.

1 . A memory hub, comprising: 
 a local queue adapted to receive local memory responses, and operable to store the local memory responses;    a bypass path adapted to receive downstream memory responses, and operable to pass the downstream memory responses;    a buffered queue coupled to the bypass path and operable to store downstream memory responses;    a multiplexer coupled to the local queue, buffered queue and bypass path, the multiplexer being operable to output responses inform a selected one of the queues or the bypass path responsive to a control signal; and    arbitration control logic coupled to the multiplexer, the arbitration logic operable to develop the control signal to control the selection of responses output by the multiplexer.    
     
     
         2 - 47 . (canceled)