The Ultrasmall soft processor
Yuichiroh Tanaka, Shimpei Sato, Kenji Kise · ACM SIGARCH Computer Architecture News · 2013
A soft processor is a processor that is implemented using logic synthesis mainly targeting programmable logic device like FPGA and it becomes a common component for FPGA designs. The supersmall soft processor (small-core) developed at University of Toronto is an unique soft processor because its main concern is very low hardware cost while supporting 32-bit ISA. With the same concept as small-core, we are developing the ultrasmall soft processor (UltraSmall) based on smallcore. The goal of this project is to implement the smallest 32-bit ISA soft processor while aiming to achieve high performance. We propose UltraSmall and describe its key ideas and implementations. The evaluation results indicate that the hardware cost of UltraSmall is smaller than smallcore in the latest FPGA while achieving 1.8x performance of small-core.