Split Boot -- True Network-Based Booting on Heterogeneous MPSoCs

TL;DR

This paper introduces 'split boot,' a network-based booting method for heterogeneous MPSoCs like Xilinx Zynq UltraScale+ devices, enabling universal firmware deployment by offloading application-specific info to network storage.

Contribution

The paper presents a novel split boot approach that separates application-specific data from the boot process, facilitating scalable firmware management for large heterogeneous MPSoC systems.

Findings

Enables universal firmware deployment across many devices.

Integrates seamlessly with existing Xilinx tools.

Reduces complexity in firmware updates and maintenance.

Abstract

In the context of the High-Luminosity (HL) upgrade of the LHC, many custom ATCA electronics boards are being designed containing heterogeneous System-on-Chip (SoC) devices, more specifically the Xilinx Zynq UltraScale+ (ZUS+) family. While the application varies greatly, these devices are regularly used for performing board management tasks, making them a fundamental element in the correct operation of the board. The large number of hundreds of SoC devices creates significant challenges in their firmware deployment, maintenance, and accessibility. Even though U-Boot on ZUS+ devices supports network boot through the Preboot Execution Environment (PXE), the standard ZUS+ boot process contains application-specific information at earlier boot steps, particularly within the First Stage Bootloader (FSBL). This prevents the initialization of several devices from a universal image. Inspired by the PXE boot process on desktop PCs, this paper describes split boot, a novel boot method tailored to the specific needs of the ZUS+. All application-specific configuration is moved to a network storage device and automatically fetched during the boot process. We considered the entire process, from firmware and software development to binary distribution in a large-scale system. The developed method nicely integrates with the standard Xilinx development toolset workflow.