Research And Implementation Of Embedded Multi-core Operating System Kernel Based On ARM Cortex-A9 MPCore

With the continuous development of chip technology, prices of multicore processors is much lower than 4,5 years ago. In linux and android operating system support, no matter it is automotive multimedia systems, or smart watches are to provide efficient and convenient services to the people through a multi-core chips. However, the study of the principles of multi-core processors and multi-core operating system is not as simple as in the single-core era. On the one hand, chip manufacturers only allow part of their products’ information to be disclosed, and do not provide bare board development support. On the other hand, although there are a lot of multi-core embedded operating system with detailed documents, most of them only provide support to the application development, the introduction of kernel principle is very limited. These problems have brought inconvenience to the study on the multi-core hardware principle and multi core operating system technology. This is the reason why embedded course in university rarely involve in multi-core technology. And also is one important reason why real hardware environment is seldom used in the experiment of multi core technology research.In order to improve the situation, this thesis choice the Zynq-7000 which contains two cpus based on ARM Cortex A9 MPCore as the research object of hardware, and analysised the principle of multicore work in multi-core processors.On the software side, this thesis studied for a single-core embedded operating system which named ucos-iii, and analyzed the SMP supportive of ucos-iii’ modules, include starting, task management, mutex&synchronization, interrupt management and time management. After that, combining with the key technology of SMP operationg system, this thesis put forward the design of ucos-iii SMP extension program.Firstly, the inter-core communication, which is based on core inter-core interrupt and shared memory is designed. Secondly, by selecting Per-CPU ready task queue model, using system calls based on the inter-core communication to extend the task management in the multi-core environment. Lastly, this thesis propsed and designed kernel lock, disabling interrupt + spin lock these two mechanisms to provide support for the multi-core extensions of mutex&synchronization.At last, basing on the expansion scheme previously proposed. This thesis implements the inter-core communication, and extend the ucos-iii on system boot, inter-core communication, task management, mutex& synchonization. In addition, the extended os-kernel which named ucos-smp have been ported to the mi-z702 embedded development board equipped with Zynq-7000 chip. A series of experimentations are also done in the real hardware environment for verifying correctness of the expansion module and testing the performance of the complete system. The results show that the realization of the ucos-smp function achieves the desired, and the performance has been significantly improved compared with ucos-iii.