Research On Fpga-based Hardware Mutex Technology Of Real-Time Operating System

With the popularity of applications on embedded systems, it has become inevitable of choosing real-time operating system (RTOS) as the infrastructure software platform. However, due to the strong real-time constraints, RTOS can not provide comprehensive safety protection in high-complexity operations such as resources competition etc. With the embedded systems being more networked, parallelized and intelligent, traditional way of reliability guarantee which relies on the application itself has become insufficient.Using synergy of hardware and software, RTOS functional modules can be remo-deled and realized in hardware, which is an effective way to guarantee real-time con-straints as well as reliability of RTOS. Thus, part RTOS implementation in hardware has become a hotspot of RTOS research.Based on the analysis of mutex module security defects in several existing RTOS, in this paper, we took FPGA as the hardware platform and did research on several key technologies in hardware mutex implementation.Then we designed and implemented a prototype system called HM-RTOS, which highly improved the reliability of the RTOS resources competition in complex scenarios.The main research work and contribution of this paper are as follows:Firstly, based on the experiment of VxWorks5.4, Rtems4.10.0, μC/OS-Ⅱ2.86, μC/OS-111, ThreadX3.0and RT-Thread0.3.0, we verified and analized defects in these implementations of priority inheritance protocol.Secondly, aiming to improving the reliability of mutex function module in RTOS, we carried out research on several key technologies in the hardware implementation of mutex module, including:the priority inheritance tree model, hardware and software interconnection morphology, hardware mutex structure design etc.Finally, we designed and implemented a prototype system named HM-RTOS which contains FPGA-based MutexMU. Its effectiveness had been verified in functional and performance tests.