Overview

Introduction

The Arm Zena CSS introduces the concept of a high-performance Arm® Cortex®-A720AE Application Processor (Primary Compute) system augmented with an Arm® Cortex®-R82AE based Safety Island and real-time domain for scenarios where additional system safety monitoring and real-time services are required. The system additionally includes a Runtime Security Engine (RSE) used for the secure boot of the system elements and the runtime Secure Services.

Throughout the following documentation, the names “CSS-Aspen” and “RD-Aspen” are used in place of Arm Zena CSS due to historical reasons. For more information, visit Arm Zena Compute Subsystem (CSS) on arm.com.

A Fixed Virtual Platform (FVP) is available as part of the Arm Zena CSS Reference Design Package. Further information on FVPs, including expected runtime performance and other capabilities, can be found at Arm Ecosystem FVPs.

This documentation, together with the FVP, allows for the exploration of baremetal-hosted Linux instances. The Primary Compute firmware stack of Trusted Firmware-A, U-Boot, and systemd-boot is also aligned with the technologies and goals of the Arm SystemReady Devicetree program.

Arm Automotive Solutions overview

The CSS-Aspen is composed of multiple Open Source components, including:

The platform consists of the following CPU cores IP:

Arm Automotive Solutions platform

Component

CSS-Aspen

Primary Compute

Cortex-A720AE Armv9.2-A

Safety Island

Cortex-R82AE Armv8-R AArch64

RSE

Cortex-M55 Armv8.1-M

The remaining software in the Primary Compute subsystem, based on the EWAOL distribution, is available in baremetal architecture. EWAOL provides Bluechi as a service controller for orchestration.

The high level CSS-Aspen Architecture is shown below.

Arm Automotive Solutions High-Level Diagram - Pre Platform Architecture

Use cases

Arm Automotive Solutions demonstrates how the following features can be used to enhance the overall functional safety level of a high-performance compute platform:

  • Arm SystemReady Devicetree-aligned software stack

  • Reliability, Availability, and Serviceability

The Reproduce section of the User Guide contains all the instructions necessary to fetch and build the source as well as to download the required FVP and launch the use cases.

Following are the main use cases implemented by the Reference Software Stack.

Arm SystemReady Devicetree validation

Arm SystemReady is a compliance certification program based on a set of hardware and firmware standards that enable interoperability with generic off-the-shelf operating systems and hypervisors.

See Arm SystemReady Devicetree for more information.

Linux Distribution Installation

Demonstrates the installation of three unmodified generic UEFI distribution images, Debian, openSUSE and Fedora, fulfilling Arm SystemReady requirements.

RAS error processing validation

Reliability, Availability, and Serviceability (RAS) aims to increase the robustness of a system by detecting hardware errors, recording them and correcting them where possible.

See Reliability, Availability, and Serviceability for more information.

Repository structure

The Arm Automotive Solutions repository (https://gitlab.arm.com/automotive-and-industrial/arm-auto-solutions/sw-ref-stack) is structured as follows:

  • arm-auto-solutions:

    • yocto

      Directory implementing the meta-arm-auto-solutions, meta-arm-bsp-extras, and meta-arm-safety-island Yocto layers as well as kas build configuration files.

    • documentation

      Directory which contains documentation sources, defined in ReStructuredText (.rst) format for building via sphinx.