External Memory Page Remapping for Embedded Multimedia Systems

As memory speeds and bus capacitances continue to rise, external memory bus power will make up an increasing portion of the total system power budget for system-on-a-chip embedded systems. Both hardware and software approaches can be explored to balance the power/performance tradeoff associated with the external memory. In this paper the authors present a hardware-based, programmable external memory page remapping mechanism which can significantly improve performance and decrease the power budget due to external memory bus accesses. The approach was developed by studying common data access patterns present in embedded multimedia applications. In the paper, they evaluate a mechanism that can perform page remapping of external memory. They also develop an efficient algorithm to map application data and instruction memory into external memory pages.