Verification Of Bridging Circuit For Bidirectional PCI-PCIe

With the rapid development of the computer's processing speed,the performance of video card,memory,CPU and other components is developed as well.The computer bus becomes the bottleneck of computer system performance.With the increasing improvement of circuit integration,the scale of chip design is expanded,the process is increased,but the research and development cycle is shortened.Traditional verification methods are difficult to meet the current research and development needs because of low efficiency,poor portability and other factors.How to ensure the effectiveness and reliability of the chip becomes increasingly important.Therefore,for more and more complex chip verification,it is highly significant to choose the appropriate verification methods and functional and powerful verification platform.The bridge chip of PCIe-PCI bus featuring with high communication speed and low power consumption is taken as the research object in the paper.It implements a bus structure which can exchange data between PCIe devices and PCI devices quickly.With taking the design scheme as the background and PCIe and PCI interface protocol as the breakthrough point,the verification content is comprehensively studied in this paper.Based on the features of complex structure and many functions of the circuit under test,the experienced manufacturer's PCI VIP and PCI IP cores are selected.And some corrections are made on VIP according to the performance of the circuit under the test,making both two cores' functions satisfy the needs of the chip.The System Verilog and the UVM are used to package and build the verification platform,improving the efficiency and the development cycle of chip and making the platform more portable.In the verification stage,System Verilog is chosen to write test cases and VIP provided by Synopsys and Xilinx is taken as the verification incentive source.A kind of the verification method that takes direct test as the main and random test as the auxiliary is used to conduct VCS simulation verification and Verdi is selected to directly observe the verification results.The detailed analysis and explanation of the relevant functional points and coverage rate are made,and test cases are further modified or added according to the coverage results at the later stage of verification.Some efforts are made to achieve the comprehensiveness and reliability of verification and to ensure the correctness of the chip in logically and functionally.Finally,the coverage rate of the verification code is more than 90%,and the functional coverage rate is 100%,through the observation of the simulation results and analysis of the coverage report,which satisfies the requirements of the design and verification scheme.