Paper

EPOCHS-1: A 12 nm Highly Heterogeneous Open-Source SoC With Distributed Coin-Based Power Management and Integrated Hybrid Voltage Regulation

Abstract

We present EPOCHS-1, a 12 nm, 64 mm2 system-on-chip (SoC) with a high degree of heterogeneity. It features four Linux-SMP-capable RISC-V cores, 14 different types of accelerators, a distributed memory hierarchy, and various peripherals. EPOCHS-1’s memory hierarchy has the flexibility to support a diverse set of accelerators and can scale to support complex applications with 34% and 25% reduction in latency and energy, respectively. A subset of the SoC’s 23 power and 35 clock domains is regulated with a fully-decentralized power-allocation scheme and hybrid unified voltage and frequency scaling (HUVFS) that combines an in-package switched regulator with a per-tile low dropout (LDO). Combined, these techniques achieve up to a 1.57× speedup versus a centralized power management baseline. Designed with an agile methodology, EPOCHS-1 is based on an open-source SoC architecture and features only open-source components, either third-party or newly designed, thus enabling design reuse for future research projects.