Verilog PCI Express Components Readme

For more information and updates: http://alexforencich.com/wiki/en/verilog/pcie/start

GitHub repository: https://github.com/alexforencich/verilog-pcie

Collection of PCI express related components. Includes full MyHDL testbench with intelligent bus cosimulation endpoints.

A MyHDL transaction layer PCI Express bus functional model (BFM) is included in pcie.py. This BFM implements an extensive event driven simulation of a complete PCI express system, including root complex, switches, devices, and functions, including support for configuration spaces, capabilities and extended capabilities, and memory and IO operations between devices. The BFM includes code to enumerate the bus, initialize configuration space registers and allocate BARs, route messages between devices, perform memory read and write operations, allocate DMA accessible memory regions in the root complex, and handle message signaled interrupts. Any module can be connected to a cosimulated design, enabling testing of not only isolated components and host-device communication but also communication between multiple components such as device-to-device DMA and message passing.

A MyHDL model of the Xilinx Ultrascale PCIe hard core is included in pcie_us.py. This module can be used in combination with the PCIe BFM to test a MyHDL or Verilog design that targets a Xilinx Ultrascale FPGA. The model currently only supports operation as a device, not as a root port.

General-purpose parametrizable arbiter. Supports priority and round-robin arbitration. Supports blocking until request release or acknowledge.

Frame-aware AXI stream arbitrated muliplexer with parametrizable data width and port count. Supports priority and round-robin arbitration.

Descriptor multiplexer/demultiplexer for PCIe AXI DMA module. Enables sharing the PCIe AXI DMA module between multiple request sources, interleaving requests and distributing responses.

PCIe in-flight tag manager.

PCIe AXI DMA module for Xilinx Ultrascale series FPGAs. Supports 64, 128, and 256 bit datapaths. Parametrizable AXI burst length. Wrapper for pcie_us_axi_dma_rd and pcie_us_axi_dma_wr

PCIe AXI DMA module for Xilinx Ultrascale series FPGAs. Supports 64, 128, and 256 bit datapaths. Parametrizable AXI burst length.

PCIe AXI DMA module for Xilinx Ultrascale series FPGAs. Supports 64, 128, and 256 bit datapaths. Parametrizable AXI burst length.

PCIe AXI master module for Xilinx Ultrascale series FPGAs. Supports 64, 128, and 256 bit datapaths. Parametrizable AXI burst length. Wrapper for pcie_us_axi_master_rd and pcie_us_axi_master_wr.

PCIe AXI master module for Xilinx Ultrascale series FPGAs. Supports 64, 128, and 256 bit datapaths. Parametrizable AXI burst length.

PCIe AXI master module for Xilinx Ultrascale series FPGAs. Supports 64, 128, and 256 bit datapaths. Parametrizable AXI burst length.

PCIe AXI lite master module for Xilinx Ultrascale series FPGAs. Supports 64, 128, and 256 bit PCIe interfaces.

Demux module for Xilinx Ultrascale CQ interface. Can be used to route incoming requests based on function, BAR, and other fields. Supports 64, 128, and 256 bit datapaths.

Demux module for Xilinx Ultrascale RC interface. Can be used to route incoming completions based on the requester ID (function). Supports 64, 128, and 256 bit datapaths.

MSI shim for Xilinx Ultrascale series FPGAs.

Parametrizable priority encoder.

Parametrizable pulse merge module. Combines several single-cycle pulse status signals together.

    arbiter.v               : Parametrizable arbiter
    axis_arb_mux.v          : Parametrizable AXI stream mux
    pcie_axi_dma_desc_mux.v : Descriptor mux for DMA engine
    pcie_tag_manager.v      : PCIe in-flight tag manager
    pcie_us_axi_dma.v       : PCIe AXI DMA module with Xilinx Ultrascale interface
    pcie_us_axi_dma_rd.v    : PCIe AXI DMA read module with Xilinx Ultrascale interface
    pcie_us_axi_dma_wr.v    : PCIe AXI DMA write module with Xilinx Ultrascale interface
    pcie_us_axi_master.v    : AXI Master module with Xilinx Ultrascale interface
    pcie_us_axi_master_rd.v : AXI Master read module with Xilinx Ultrascale interface
    pcie_us_axi_master_wr.v : AXI Master write module with Xilinx Ultrascale interface
    pcie_us_axil_master.v   : AXI Lite Master module with Xilinx Ultrascale interface
    pcie_us_axis_cq_demux.v : Parametrizable AXI stream CQ demux
    pcie_us_axis_rc_demux.v : Parametrizable AXI stream RC demux
    pcie_us_msi.v           : MSI shim for Xilinx Ultrascale devices
    priority_encoder.v      : Parametrizable priority encoder
    pulse_merge             : Parametrizable pulse merge module

Running the included testbenches requires MyHDL and Icarus Verilog. Make sure that myhdl.vpi is installed properly for cosimulation to work correctly. The testbenches can be run with a Python test runner like nose or py.test, or the individual test scripts can be run with python directly.

    tb/axis_ep.py        : MyHDL AXI Stream endpoints
    tb/pcie.py           : MyHDL PCI Express BFM
    tb/pcie_us.py        : MyHDL Xilinx Ultrascale PCIe core model