Design And Implementation Of An Automotive Embedded Real-Time Operating System Kernel Supporting Homogeneous Multicore

With the growing complexity of automotive electronic control systems, and thecontradiction between performance and power consumption in vehicle microprocessorbecoming increasingly prominent, multicore microprocessor will be irreversiblyintroduced into the area of high-end automotive electronics in the future, which willbrings new challenges to the real-time operating system in this area.Based on the research of the real-time operating system kernel namedTOPPERS/ASP for single-core system, we designed and implemented an embeddedreal-time operating system kernel prototype named MCORE-OS supportinghomogeneous multicore microprocessor in this paper, which combines hardwarefeatures of multicore microprocessor and characteristics of automotive electronicstogether. The main works involved is as following: First, according to the μITRON4.0standards and combining with the application requirements of multicoremicroprocessor environment, problems of the open source kernel TOPPERS/ASP inmulticore microprocessor environment are researched and analyzed. Meanwhile, areal-time operating system architecture is proposed which is friendly extendable inthe number of processor cores and able to support homogeneous multicoremicorprocessor. Accurately speaking, the proposed architecture includes systemarchitecture model and parallel task scheduling model.After that, combining the characteristics of current automotive electronics, amulticore supporting scheme is proprosed. The scheme is composed of three parts.One is the inter-core system call mechanism, which is based on inter-core interruptand shared memory, and used for the problem of inter-core communication amongrunning entities. The second is the task migration and automaitc migration mechanismwhich is based on inter-core system call and designed for solving the problem of loadbalancing among cores. The third is the spin-lock mechanism based on“read-modify-write” atomic operation and used for exclusive access to resourcesshared by all processor cores.Finally, based on the previously proposed multicore supporting scheme, theTOPPERS/ASP is extended and improved on system boot, task scheduler, dispatcher,synchronization&communication, interrupt handler, time management and memorymanagement etc. Related coding, testing and debugging works are also done. In addition, the MCORE-OS is successfully ported to the PwerPC MPC8641D dual-coremicroprocessor, and the extended and added components are tested and verified onthat platform. The test results show that the overall performance of MCORE-OS isstable currently on the experimental platform built on the PowerPC MPC8641Ddual-core processor.