Applications of ARM Architecture in Automotive Electronics Chips
Author | AnonymousProduced by | Automotive Electronics and Software#01ARM ProcessorsCurrently, a significant portion of the processors used in controllers responsible for core vehicle control functions are based on the ARM architecture. This architecture occupies a crucial position in the automotive electronics field due to its excellent energy efficiency, broad ecosystem support, and high flexibility. Therefore, this article aims to briefly introduce the characteristics of ARM architecture processors for discussion and exchange.
ARM is a British company that designed the first low-power cost RISC microprocessor, the ARM processor (Advanced RISC Machines). After the classic ARM11 processor, ARM’s products began to adopt the Cortex naming convention and were divided into A, R, and M categories to serve various markets. The Cortex series belongs to the ARMv7 architecture, which was the latest instruction set architecture from ARM at that time. Therefore, it can be said that Cortex is a series of processors launched by ARM, with origins tracing back to ARM’s processor design and development history.#02ARM Instruction SetFirst, let’s briefly explain a concept: what is the instruction set of a chip processor? The instruction set mainly refers to the interface description between CPU hardware and software, which is essentially a segment of binary machine code. The CPU can only recognize and execute these machine code instructions, and the machine code itself is a string of meaningless characters, making it difficult for programmers to understand and use. Therefore, people invented assembly language and other high-level programming languages, which have a one-to-one correspondence with machine code, allowing programmers to write and debug programs more conveniently.The instruction set can be divided into various types, with the most notable being Complex Instruction Set Computing (CISC) and Reduced Instruction Set Computing (RISC).
Complex Instruction Set Computing (CISC):This type of instruction set contains a large number of instructions, and each instruction has a relatively complex function. The x86 instruction set is a typical example of a CISC instruction set.
Reduced Instruction Set Computing (RISC):In contrast to CISC, the RISC instruction set contains fewer instructions, and each instruction has a relatively simple function. The ARM instruction set is a representative of the RISC instruction set and is widely used in mobile devices, embedded systems, and other fields.
We often hear terms like “ARM architecture chips,” which actually refer to the specific instruction set used by a particular processor. Currently, the mainstream chip architectures on the market are X86, ARM, RISC-V, and MIPS.
In most cases, architecture equals instruction set. For example, if a processor is based on the ARMv7 architecture, then it uses the ARMv7 instruction set. The instruction set architecture is part of computer architecture, which defines the set of instructions that the processor can recognize and execute. The ARM architecture also has v8 and v9 versions, with v7 being an earlier version and one of the most widely used ARM architecture versions. The ARMv7 architecture is divided into the A series (Application Processors for high-performance products), R series (Real-time Processors for real-time systems), and M series (Microcontroller Processors for microcontrollers); ARMv9 is the latest version of the ARM architecture, with a rough comparison of the instruction sets as follows:
ARMv7:
It introduced a new instruction set, such as Thumb-2, which is a new instruction set that mixes 32-bit and 16-bit instructions, providing high performance while saving storage space.
ARMv7 also supports hardware floating-point operations (VFPv3), enhancing the processor’s capability to handle floating-point numbers.
ARMv8:
This is the first 64-bit architecture version introduced by ARM.
It supports both 64-bit and 32-bit applications, providing a larger address space, more registers, and enhanced security features.
ARMv8 introduced a new instruction set AArch64 for executing 64-bit operations.
This architecture also improved support for floating-point and SIMD (Single Instruction, Multiple Data), including new floating-point operation instructions and new SIMD instructions optimized for multimedia and data processing.
ARMv8 also introduced hardware virtualization support, improving the performance of running applications in virtual environments.
ARMv9:
ARMv9 has undergone a series of optimizations and improvements over previous versions to enhance the performance and efficiency of processors.
It introduced new SVE2 (Scalable Vector Extension 2) technology, which is a vector computation technology that can significantly enhance the processor’s ability to handle machine learning and artificial intelligence tasks.
ARMv9 also enhances security features, introducing a new Realm management architecture to more effectively prevent various cyber attacks and data leaks.
This architecture has improved virtualization support, making virtualization more efficient in cloud computing and other high-performance computing applications.
In simple terms, the instruction set is the bridge between the CPU and software, allowing software to correctly control the CPU to perform various operations. At the same time, the instruction set also determines key indicators such as CPU performance and power consumption. Different instruction sets have different characteristics and advantages, making them suitable for different application scenarios.
#03Applications of Cortex Core Chips in VehiclesThe ARM Cortex series chips commonly used in automotive controllers mainly belong to the ARMv7 and v8 architectures.ARM Cortex series chips are divided into A, R, and M series, which is also the origin of the chip A core and M core terminology we often hear.Cortex-A is a high-end processor aimed at markets such as mobile computing, smartphones, and servers, with high operating frequencies (>1GHz), supporting memory management units required by operating systems like Linux, Android, and Windows. In the automotive field, it can be used for cockpit chips, intelligent driving chips, central computing platform chips, etc.
Cortex-R is used for real-time applications, such as body controllers, automotive chassis systems, and power system control, not supporting memory management units but possessing other storage functions, with high operating frequencies (200MHz to >1GHz), low response latency, and supporting real-time operating systems rather than full Linux and Windows.
Cortex-M is compact and energy-efficient, with lower clock frequencies but some reaching over 200MHz. The new Cortex-M series is easy to use and widely popular in microcontrollers and deeply embedded systems, and can also be used for body control, although its performance is slightly inferior to Cortex-R.Chip Architecture of Xinchih X9 SeriesThe gateway chip G9 series, intelligent driving chip V9 series, and cockpit chip X9 series from the domestic chip manufacturer Xinchih mainly use Cortex-A55+Cortex-R5 as their main processors, forming a multi-core heterogeneous chip.Chip Architecture of Xinchih E3 SeriesHowever, the main chip series E3 launched by Xinchih for vehicle control and domain control does not use Cortex-A, but rather Cortex-R5 and Cortex-R52+, because the E3 MCU is a new generation of high-performance microcontroller product designed for automotive safety-related applications, and based on this requirement, Cortex-R series processors with good real-time performance and high safety were chosen instead of Cortex-A.NXP S32G399A Architecture DiagramFor example, NXP’s domain control and gateway series products S32G series choose a processor core configuration of Cortex-M7+Cortex-A53, with the highest-end product S32G399A having 4 Cortex-M7 and 8 Cortex-A53, this heterogeneous configuration allows the entire SoC to have high computing power while meeting ASIL D safety standards on Cortex-M.S32K3 Series Processor CompositionAdditionally, NXP’s S32K3 series chips have applications in power management, inverter control, body area control, etc. This series has multiple Cortex-M7 cores, some of which also have dual lock-step Cortex-M7, dual-core lock-step (DCLS) is a CPU redundancy technology that includes two identical processors in one chip, which operate in a master-slave relationship. They execute the same code and are strictly synchronized, and critically, the dual-core lock-step technology can quickly monitor and isolate errors in processor operation through hardware redundancy and comparison mechanisms, preventing the spread of failures.S32K39x (x=4 or 6) Chip Block DiagramRenesas’s MCU/MPU/SoC products also widely use ARM architecture cores.Renesas’s R-Car H3e ArchitectureRenesas’s R-Car H3e (-2G) is a high-end computing automotive SoC, with core processors including four Cortex-A57, four Cortex-A53, and dual lock-step Cortex-R7, providing powerful computing performance capable of accurately processing vast amounts of information from automotive sensors in real time. Its applications are very broad, such as in-vehicle entertainment information systems and integrated cockpits. It meets ISO 26262 (ASIL-B) automotive functional safety standards and information security requirements. The (H3e-2G) operating at 2GHz maintains hardware and software compatibility while enhancing processing capability.
In summary, the ARM architecture plays an important role in automotive electronics due to its low power consumption, high performance, and customizability. With continuous technological development and innovation, there is still huge potential for the ARM architecture’s growth. By selecting appropriate cores, optimizing code, using hardware acceleration, and optimizing memory access, system performance and power efficiency can be further improved to meet the needs of various application scenarios./ END /
