Research On The Realization Of Automatic Driving Control Software And Hardware Architecture Based On Multiple Multi-core Processors

With the continuous development of automatic driving,higher and higher requirements have been placed on the computing power of the automatic driving controller.Traditional single-core processors have been unable to meet the computing power requirements of automatic driving,and multi-core processors have begun to get more and more application.In addition,functional safety is also an important issue that needs to be solved in automatic driving.In order to improve the functional safety of automatic driving controller,redundancy technology has begun to be gradually applied to the design of automatic driving controllers.Therefore,this paper studies the application of multi-core processors in automatic driving control and the redundant design method of automatic driving controllers,and proposes a dual-redundant automatic driving controller hardware architecture based on multi-core processors,and based on this hardware architecture,designed the automatic driving control software architecture.This paper firstly carried out the hardware design of the automatic driving controller.In view of the controller’s computing power and functional safety requirements,the multi-core processor TC297,which can reach the highest functional safety level ASIL-D,was selected,and on this basis,the controller was designed with dual-system redundancy.The two systems communicate through HSSL,SPI,CAN,and ERU.On the one hand,the two systems can perform fault detection with each other to achieve redundant functions.On the other hand,the two processors can work together to further improve the controller’s computing power.On the basis of the hardware architecture design,the circuit design of the controller was carried out,including the design of the circuit schematic diagram and the design of the printed circuit board,and the physical design of the automatic driving controller was completed through PCB processing and component welding,so as to provide a hardware foundation for the development of automatic driving control software architecture.In response to the system startup and application upgrade requirements of the automatic driving controller,the system basic software Bootloader is designed.In order to make the controller start normally,a system startup program is designed to set the clock system and memory of the processor to establish the correct application program operating environment,and to set the registers,stacks and cache of each core.In order to ensure that the multi-core can start and run normally;in order to solve the problems of application executable file download,format conversion and programming,the application executable file download program is designed;in order to enable the Bootloader to complete the system startup and application upgrade work After smoothly jumping to the application program entrance and starting to run the application program,the jump program was designed with related instructions;in order to make the Bootloader use the program memory space reasonably,the program memory space allocation scheme was designed.In response to the real-time operation requirements of automatic driving tasks and the requirements of multi-core cooperative operation,the basic software of multi-core processors is designed.In order to make the operation of automatic driving tasks have high real-time performance,asymmetric multi-processing is selected as the operating mode of the multicore processor,and the real-time operating system Free RTOS is transplanted on the processor;in order to meet the inter-core tasks during multi-core cooperative operation For synchronization requirements,the inter-core task synchronization mechanism is designed by using the inter-core interrupt;in order to solve the problem of mutual conflicts due to simultaneous access to shared resources during multi-core cooperative operation,the special hardware instructions of the processor are used to design the mutual exclusive access mechanism of shared resources between cores;In order to meet the data communication requirements of multi-core cooperative operation,the method of shared memory is adopted,and the inter-core communication mechanism is designed in combination with the inter-core task synchronization mechanism.Aiming at the functional safety requirements of the automatic driving controller,the dual-redundant system software design is carried out on the basis of the dual-redundant controller hardware platform.In order to enable the two redundant systems in the controller to obtain the working status information of themselves and each other after startup,and to make the two systems enter the correct operating state,the system status information management program is designed;in order to make the two systems run synchronously In order to avoid misjudgment of faults,a synchronization protocol and corresponding synchronization procedures between systems are designed;in order to ensure that the occurrence of the fault can be quickly detected and handled correctly when the system fails,the system faults between and within the system are designed Testing and processing procedures.In order to verify the correctness of the software and hardware design,different test cases were designed and tested for each functional module of Bootloader,multi-core processor basic software and dual-redundant system software.According to the relevant test results,the correctness of the software and hardware of the automatic driving controller designed in this paper is verified.