Pai, Vinayak (2010-12). HW/SW Codesign and Design, Evaluation of Software Framework for AcENoCs : An FPGA-Accelerated NoC Emulation Platform. Master's Thesis. Thesis uri icon


  • Majority of the modern day compute intensive applications are heterogeneous

    in nature. To support their ever increasing computational requirements, present

    day System-on-Chip (SoC) architectures have adapted multicore style of modeling,

    thereby incorporating multiple, heterogeneous processing cores on a single chip. The

    emerging Network-On-Chip (NoC) interconnect paradigm provides a scalable and

    power-efficient solution for communication among multiple cores, serving as a powerful

    replacement for traditional bus based architectures. A fast, robust and


    emulation platform is the key to successful realization and validation of such architectures

    within a very short span of time.

    This research focuses on various aspects of Hardware/Software (HW/SW) codesign

    for AcENoCs (Accelerated Emulation Platform for NoCs), a Field Programmable

    Gate Array (FPGA) accelerated, con gurable, cycle accurate platform for emulation

    and validation of NoC architectures. This work also details the design, implementation

    and evaluation of AcENoCs' software framework along with the various design

    optimizations carried out and tradeoffs considered in AcENoCs' HW/SW codesign

    for achieving an optimum balance between emulated network dimensions and emulation

    performance. AcENoCs emulation platform is realized on a Xilinx Virtex-5

    FPGA. AcENoCs' hardware framework consists of the NoC built using configurable

    hardware library components, while the software framework consists of Traffic Generators

    (TGs) and their associated source queues, Traffic Receptors (TRs) along with statistics analysis module and dynamically controlled emulation clock generator. The

    software framework is implemented using on-chip Xilinx MicroBlaze processor. This

    report also describes the interaction between various HW/SW events in an emulation

    cycle and assesses AcENoCs' performance speedup and tradeoffs over existing FPGA

    emulators and software simulators.

    FPGA synthesis results showed that networks with dimensions upto 5x5 could be

    accommodated inside the device. Varying synthetic traffic workloads, generated by

    TGs, were used to evaluate the network. Real application based traces were also run

    on AcENoCs platform to evaluate the performance improvement achieved in comparison

    to software simulators. For improving the emulator performance, software

    profiling was carried out to identify and optimize the software components consuming

    highest number of processor cycles in an emulation cycle. Emulation testcases

    were run and latency values recorded for varying traffic patterns in order to evaluate

    AcENoCs platform. Experimental results showed emulation speedups in order

    of 10000-12000X over HDL (Hardware Description Language) simulators and 14-47X

    over software simulators, without sacri cing cycle accuracy.

publication date

  • December 2010