Polyblaze: From one to many bringing the microblaze into the multicore era with Linux SMP support

Modern computing systems increasingly consist of multiple processor cores. From cell phones to datacenters, multicore computing has become the standard. At the same time, our understanding of the performance impact resource sharing has on these platforms is limited, and therefore, prevents these systems from being fully utilized. As the capacity of FPGAs has grown, they have become a viable method for emulating architecture designs as they offer increased performance and visibility into runtime behaviour compared to simulation. With future systems trending towards asymmetric and heterogeneous systems, and thus further increasing complexity, a framework that enables research in this area is highly desirable. In this work, we present PolyBlaze: a multicore Micro- Blaze based system with Linux Symmetric Multi-Processor (SMP) support on an FPGA. Starting with a single-core, Linux supported, MicroBlaze we detail the changes to the platform, both in hardware and software, required to bring Linux SMP support to the MicroBlaze. We then outline the series of tests performed on our platform to demonstrate both its stability (e.g. more than two weeks of up time) and scalability (up to eight cores on an FPGA, with resource usage increasing linearly with the number of cores).