The field of edge computing has witnessed remarkable growth owing to the increasing demand for real-time processing of data in applications. However, challenges persist due to limitations in performance and power consumption. To overcome these challenges, heterogeneous architectures have emerged that combine host processors with specialized accelerators tailored to specific applications, leading to improved performance and reduced power consumption. However, most of the existing platforms lack the necessary configurability and extendability options for integrating custom accelerators. To overcome these limitations, we introduce in this paper the eXtendible Heterogeneous Energy-Efficient Platform (X-HEEP). X-HEEP is an open-source platform designed to natively support the integration of ultra-low-power edge accelerators. It provides customization options to match specific application requirements by exploring various core types, bus topologies, addressing modes, memory sizes, and peripherals. Moreover, the platform prioritizes energy efficiency by implementing low-power strategies, such as clock-gating and power-gating. We demonstrate the real-world applicability of X-HEEP by providing an integration example tailored for healthcare applications that includes a coarse-grained reconfigurable array (CGRA) and in-memory computing (IMC) accelerators. The resulting design, called HEEPocrates, has been implemented both in field programmable gate array (FPGA) on the Xilinx Zynq-7020 chip and in silicon with TSMC 65 nm low-power CMOS technology. We run a set of healthcare applications and measure their energy consumption to demonstrate the alignment of our chip with other state-of-the-art microcontrollers commonly adopted in this domain. Moreover, we showcase the energy benefit of 4.9 x gained by exploiting the integrated CGRA accelerator, compared to running on the host CPU.

翻译：边缘计算领域因应用中对数据实时处理需求的增长而取得了显著进展。然而，性能与功耗限制仍带来持续挑战。为克服这些挑战，异构架构应运而生，将主处理器与针对特定应用优化的专用加速器相结合，从而提升性能并降低功耗。但现有多数平台在集成定制加速器时缺乏必要的可配置性与可扩展性。针对这一局限，本文提出了可扩展异构高能效平台（X-HEEP）。X-HEEP是一个开源平台，旨在原生支持超低功耗边缘加速器的集成。通过探索多种核心类型、总线拓扑、寻址模式、存储器容量及外设，该平台提供了匹配特定应用需求的定制选项。此外，平台通过实现时钟门控和电源门控等低功耗策略，优先保障能效。我们通过一个面向医疗应用的集成示例——包含粗粒度可重构阵列（CGRA）和存内计算（IMC）加速器——展示了X-HEEP的实际应用价值。该设计（称为HEEPocrates）已在Xilinx Zynq-7020芯片上的现场可编程门阵列（FPGA）以及采用台积电65纳米低功耗CMOS工艺的硅片中实现。我们运行一组医疗应用并测量其能耗，以证明该芯片与该领域普遍采用的其他先进微控制器性能一致。此外，与在主CPU上运行相比，利用集成的CGRA加速器可带来4.9倍的能效提升。