With the increasing deployments in IP Cores in FPGA applications

SoC-FPGA systems have been gaining wide popularity in recent years. Processor is no doubt the heart of a SoC-FPGA system

and has a critical impact on overall system performance. The utilization of open source processor IPs can greatly improve working efficiency and reduce the development cycle of SoC-FPGA systems

and it has been gaining favor as a commonly adopted design methodology. This paper investigates the key technical indicators of existing open-core projects

and provides an overview of open source processors. The major features of open source processors are summarized in terms of usability and stability

and the authors propose a methodology to choose appropriate processors for specific applications. Following these guidelines

some open source processors are selected and implemented on Stratix V and Virtex-7 FPGA platforms using corresponding EDA tools. The implementation results are compared and discussed.