• Arm’s Zena CSS features a safety island, secure enclave and a 16-core CPU cluster. It is designed to work with other Arm IP, such as Mali GPU and ISP.
• Arm says its Zena CSS subsystem can reduce silicon development times by 12 months.
• Greater standardization will help semiconductor companies focus on value addition in the automotive industry.

The automotive industry is at a major inflection point with the rapid advancement of advanced driver assisted system (ADAS) and autonomous driving, electrification, and in-vehicle infotainment and connectivity. To support this range of features, automakers are moving from traditional distributed vehicle architectures to more zonal and centralized software-defined platforms. One aspect of this transition is evident from the evolution of the processors that these systems run their software on. Semiconductor companies like Qualcomm, NVIDIA, NXP, Renesas and Samsung have developed system-on-chip (SoC) solutions that feature a safety island to support mixed-criticality workloads.

To help reduce the time required to develop these types of processors, semiconductor and software design company Arm has launched new, automotive-specific semiconductor IP called Arm Zena Compute Subsystems (CSS).

Arm Zena CSS is built on Armv9 Automotive Enhanced (AE) technology and is the company’s first pre-integrated and pre-validated platform that provides compute cores, a safety island, and a security enclave in a subsystem designed to support next-generation automotive electronics systems. Arm Zena CSS can also integrate Arm’s Mali GPU and ISP IP to support ADAS functions, including surround view and driver monitoring. In addition, Arm Zena CSS can integrate accelerators to support AI workloads. According to Arm, Zena CSS can help the industry develop “AI-defined” vehicles more rapidly, which aligns with the primary and optional IP the company offers with this subsystem.

Need for dedicated automotive compute subsystem

The automotive industry’s needs differ significantly from those of mobile, consumer or data center industries. Vehicles operate in real-time, safety-critical conditions where deterministic performance, resilience to failure and long lifecycles are mandatory.

To meet these demands, Arm’s Zena CSS combines several types of Arm IP, including 16 Armv9-based Cortex-A720AE cores that the company noted it optimized for ADAS and digital cockpit applications, Arm’s Cortex-R82AE for the safety island that supports real-time processing, chip-to-chip I/O connectivity using Arm’s CMN S3AE, and Arm TrustZone for the security enclave that acts as a system-wide root of trust and that can support secure, over-the-air updates. The Arm Cortex-R82AE features fault management, safety monitoring, system control, and SoC boot.

Arm Zena CSS Block Diagram

Zena CSS is designed to support monolithic and chiplet-based SoC designs via modular interconnects, such as Arm CMN S3AE. The company has not publicly confirmed support for other standards, such as UCIe.

Another key feature Arm announced is virtual prototyping support, which the company originally announced for its IP in 2024 alongside its commitment to developing new automotive semiconductor subsystem IP. The company’s initial launch of virtual versions of its IP was for Cortex-A720AE and Cortex-R82AE in 2024. With the launch of Zena CSS, cloud-based virtual support of this compute subsystem is also available from its partners, including AWS, Cadence, Siemens and Synopsys.

Analyst take

Integrating this IP into a subsystem is another step on the roadmap for Arm’s Automotive Enhanced (AE) portfolio of semiconductor IP that the company announced in 2024. Arm originally announced its Cortex-R82AE safety island IP with its plan to develop more automotive semiconductor-specific subsystems to help customers shrink development cycle timelines. With the launch of its Zena CSS subsystem, the company has followed through on its original plan to launch its first subsystem in 2025.

Although many of the semiconductor companies have developed products with safety islands and security features, it makes sense for Arm to develop a subsystem with these features that any company could license. Having a safety island and security features is no longer truly differentiating. With many automakers looking to shorten development timelines, Arm’s new subsystem can enable semiconductor companies to reduce their own development cycles by up to 12 months, which in turn enables them to focus on other areas where they can differentiate their products more effectively.

Although it is apparent that many semiconductor products used by automakers are Arm-based, the company noted in its announcement of Zena CSS that 94% of global automakers use semiconductors with Arm’s technology. In the last 5 years, the company has seen a 3X increase in Arm-based chip shipments into the automotive industry and has grown its automotive customer base 1.6X. These data points clearly demonstrate that Arm has a strong interest in the automotive segment and a commitment to developing IP that meets the industry’s growing range of requirements.

In addition, some automakers have been developing their own semiconductors and may want to license IP from companies such as Arm. Examples of those doing so include Stellantis, with its SiliconAuto joint venture with Foxconn, and several automakers headquartered in China, including Great Wall, Li Auto, NIO and Xpeng. With its new Zena CSS family, Arm can offer solutions such as this to automakers in general, though Arm has not publicly shared information about specific OEM engagements.

Arm has been active in many areas of not only automotive semiconductor development but also software, with the company launching the SOAFEE special interest group (SIG) with its automaker and supplier partners in 2021. The combination of its software-related efforts (and the growing number of companies that are part of SOAFEE) and its follow-through for its semiconductor IP roadmap indicate that although the automotive industry may be facing challenges, there is still demand from automakers and their suppliers to develop new platforms that use next-generation technologies. This demand will benefit not only Arm but also its wide range of partners in the industry as they focus on meeting automotive industry requirements.