OpenCL memory infrastructure for FPGAs (abstract only)

Abstract

Programming models assist developers in creating high performance computing systems by forming a higher level abstraction of the target platform. OpenCL has emerged as a standard programming model for heterogeneous systems and there has been recent activity combining OpenCL and FPGAs. This work introduces memory infrastructure for FPGAs and is designed for OpenCL style computation, complementing previous work. An Aggregating Memory Controller is implemented in hardware and aims to maximize bandwidth to external, large, high-latency, high-bandwidth memories by finding the minimal number of external memory burst requests from a vector of requests. A template processing array with soft-processor and hand-coded hardware elements was also designed to drive the memory controller. The Aggregating Memory Controller is described in terms of operation and future scalability and the created processing array is described as a flexible structure that can support many types of processing solutions. A hardware prototype of the memory controller and processing array was implemented on a Virtex-5 LX110T FPGA. Two micro-benchmarks were run on both the soft-processor elements and the hand-coded hardware cores to exercise the memory controller. Results for effective memory bandwidth within the system show that the high-latency can be hidden using the Aggregating Memory Controller by increasing the number of threads within the processing array.