How to integrate Arm STL for a safer Automotive experience

The automotive industry is rapidly evolving, with new safety technologies being developed to prevent accidents. These technologies can only work if they are based on dependable and reliable computing platforms, which depend in turn on mechanisms such as Software Test Libraries (STLs). Two recent white papers delve into the integration of Arm's STL into Classic AUTOSAR, and microcontroller hypervisors based on the Armv8-R architecture.

It’s essential to ensure that the hardware works correctly across high-reliability automotive systems. Common methods these days to check the integrity of the silicon include Built-In Self-Tests (BIST) for memory (MBIST) and CPU logic (LBIST). For the highest safety standards, an evolved industry standard is Dual-Core Lock-Step (DCLS).

In addition to hardware integrity checks, software tools like the Arm Self-Test Library (STL) offer an efficient and cost-effective way to enhance system reliability. STLs can be executed within a running application environment to ensure smooth operation. Integrating Arm’s STL into automotive systems boosts the reliability of safety-related applications, such as advanced driver assistance systems (ADAS), all while meeting stringent ISO26262 standards.

For more information, see the following guides from Arm and ETAS for more on using STL in specific situations:

Classic AUTOSAR and Arm STL: Enhancing Diagnostic Capabilities

Classic AUTOSAR has established itself as a standardized framework for real-time deterministic automotive software, offering a modular and scalable approach to ECU development. The integration of Arm STL into Classic AUTOSAR brings various benefits.

• Robust Fault Detection: Arm STL offers a comprehensive suite of diagnostic tests to verify the correct operation and integrity of Arm-based microcontrollers, including Cortex-M and Cortex-R. This ensures that faults are detected early, preventing potential failures in critical automotive functions.
• Improved Reliability: By integrating STL, developers can enhance the reliability of their ECUs, ensuring that the hardware operates correctly before the application runs. This is crucial for meeting stringent Automotive Safety Integrity Level (ASIL) requirements.
• Flexible Integration: The white paper outlines various methods for integrating STL with classic AUTOSAR, including out-of-reset, and online event scenarios. This flexibility allows developers to choose the best approach for their specific application needs.

Click here to read the full white paper on integrating Arm STL into Classic AUTOSAR.

Read the white paper

Microcontroller Hypervisors and Arm STL: Consolidating Applications with Safety

The introduction of microcontrollers hypervisors, based on the Armv8-R architecture, marks a significant advancement in automotive technology. These hypervisors enable consolidation of multiple applications into a single ECU, thus ensuring freedom from interference and supporting mixed criticality systems. Integrating Arm STL into this architecture offers several advantages:

• Enhanced Fault Mitigation: The hypervisor's ability to separate applications is crucial for maintaining system integrity. By running STL at the hypervisor level (EL2), developers can achieve high diagnostic coverage, ensuring that faults are detected and mitigated effectively.
• Scalable and Flexible Systems: The integration strategies described in the white paper allow for flexible and scalable system designs. Whether running STL during boot-time or periodically during operation, developers can tailor the integration to meet their specific safety and performance requirements.
• Support for Mixed-Criticality Systems: The ability to run multiple software stacks on a single ECU, with assured spatial and temporal separation, is a game-changer. This supports the development of systems where applications of varying safety levels can coexist without compromising overall system integrity.

See the following link to read the full white paper on integrating Arm STL into microcontroller hypervisors.

Read the white paper

Beyond STL: Getting Safety Certification

While STL is important for meeting ASIL targets for ISO26262, these white papers do not cover the full process for getting Functional Safety certification.

To that effect, the following white paper provides a comprehensive guide to integrating Arm STL in an application execution context, offering practical strategies and insights that can help developers navigate the complexities of modern automotive software development. As we move towards a future where automotive systems are increasingly complex and interconnected, these integrations will play a crucial role in ensuring safety and performance.

For more details on safety certification, check out the joint Exida and Arm paper State of the Art Software Test Libraries (STL) and ASIL B: Truths, Myths, and Guidance.

Read the white paper