It is foreseeable that auto parts demand will usher in the outbreak in the next few years. Therefore, it is not surprising that companies continue to claim solutions designed for such vehicles. In September 26th, the world's leading semiconductor intellectual property (IP) provider Arm launched the Safety Ready program to provide solutions for self driving cars. In addition, Arm has launched a product named Cortex-A76AE, which is built for the first autopilot car.processor.
"Safe readiness" plan
In fact, Arm has been in the automotive industry for a long time. Since 1996, the universal and real-time processors produced by Arm have been used by major vehicle manufacturers. Arm's IP is now widely used in ADAS systems (such as crashproof, cruise control, etc.), connectivity, information entertainment, power assembly control, and other automotive components.
The Arm "safety readiness" plan is a multi-year program designed to drive autopilot.DevelopmentAutomotive enhanced (AE) custom and semi custom solutions. Arm is currently offering solutions for L3-class automation and will be offering products for L4 and L5-class automation around 2020.
Arm's "Security Readiness" program covers the company's existing security products as well as new or future products, including one-stop software, tools, components, certification and standards. These products are developed using a rigorous functional security process, supporting ISO 26262 and IEC 61508 technical standards.
At present, Arm only talks about Cortex-A76AE processors for autopilot, but in this huge plan, it also includes vehicle enhanced processors based on Helios and Hercules microarchitecture, and plans to provide AE versions of Cortex-R processors around 2020. Although Arm is preparing to make its future IP more AE-style, it will continue to supply existing kernels to SoC developers in the automotive sector, such as Cortex-A72, Cortex-R5, Cortex-R52, Cortex A53, Cortex-M4, Cortex-M7, Cortex-M44, etc.
The implementation of the "safety readiness" plan will enable car manufacturers to acquire IP and make the automatic driving system more energy efficient and cheaper, thereby reducing vehicle manufacturing costs.
The first member of the Cortex-A76AE:AE family of Arm.
As Arm's first integrated feature-safe autopilot processor, Cortex-A76AE, has up to 16 Cortex-A76 cores with all the features of the Arm v8.2 microarchitecture, including reliability, availability and maintainability, and uses Split-Lock mode to ensure reliability.
In fact, SoC based on Cortex-A76AE can be expanded to up to 64 cores. In addition to the general purpose computing core, Arm's autonomous computing complex integrates Mali-G76 GPU, ARM's ML processor, and other necessary IP. In addition, all of the complexes support Arm's memory virtualization and protection technology, which makes it possible to run ML and NN accelerators perfectly.
According to Arm's official statement, the 30-watt 16-core Cortex-A76AE SoC manufactured using TSMC's 7Nm technology has computational performance exceeding 250 KDMIPS, sufficient to meet today's application requirements. If users want higher performance, they can build more cores or even more SoC.
For automatic driving vehicles, performance indicators are very important. Nowadays, L3 level self driving vehicles can run multiple programs at the same time. The software of the ArmL5 class autopilot will contain 1 billion lines of code. Compared to the Boeing 787 Dreamliner, the software contains 14 million lines of code.
Split-Lock of Arm: redundancy calculation in hardware
Cortex-A76AE uses the key technology Split-Lock, which allows SoC developers to use the kernel in two modes: in the kernel mode, two (or four) independent CPUs in the cluster can be used for various tasks and applications to achieve higher performance; in the lock-step mode, the CPU will be in the lock-step state. Create a pair (or two pairs) of lock-step CPUs in the cluster that run the same code, and if an exception is monitored, it will report an error to the system and let the failover mechanism take over (or at least notify the driver) to achieve higher car safety.
Arm lock-step mode is somewhat similar to HP's NonStop fault-tolerant system, but the key difference is that Arm's solution is entirely hardware-dependent and therefore compatible with any software, such as AutoWare, Deepscale, Linaro, Linux, QNX, and so on.
In order to meet the highest level of vehicle safety ASIL-D application, Arm adopts locking step cluster, which is very important for safety. In contrast, the sub cluster is suitable for ASIL-B applications such as infotainment. Given Arm's hardware flexibility, any automobile manufacturer can run almost all software in a kernel-lock mode, while ensuring high performance and zero error.