2.3.1. Testbench
The testbench uses a test driver module, altpcietb_bfm_rp_gen4_x16.sv, to initiate the configuration and memory transactions. At startup, the test driver module displays information from the Root Port and Endpoint Configuration Space registers, so that you can correlate to the parameters you specified using the Parameter Editor.
The example design and testbench are dynamically generated based on the configuration that you choose for the P-Tile IP for PCIe. The testbench uses the parameters that you specify in the Parameter Editor in Intel® Quartus® Prime.
This testbench simulates up to a ×16 PCI Express link using the serial PCI Express interface. The testbench design does allow more than one PCI Express link to be simulated at a time. The following figure presents a high level view of the PIO design example.
Figure 17. PIO Design Example Simulation Testbench
The top-level of the testbench instantiates the following main modules:
- altpcietb_bfm_rp_gen4x16.sv —This is the Root Port PCIe* BFM.
//Directory path <project_dir>/intel_pcie_ptile_ast_0_example_design/pcie_ed_tb/ip/pcie_ed_tb/dut_pcie_tb_ip/intel_pcie_ptile_tbed_<ver>/sim - pcie_ed_dut.ip: This is the Endpoint design with the parameters that you specify.
//Directory path <project_dir>/intel_pcie_ptile_ast_0_example_design/ip/pcie_ed - pcie_ed_pio0.ip: This module is a target and initiator of transactions for the PIO design example.
//Directory path <project_dir>/intel_pcie_ptile_ast_0_example_design/ip/pcie_ed - pcie_ed_sriov0.ip: This module is a target and initiator of transactions for the SR-IOV design example.
//Directory path <project_dir>/intel_pcie_ptile_ast_0_example_design/ip/pcie_edFigure 18. SR-IOV Design Example Simulation Testbench
In addition, the testbench has routines that perform the following tasks:
- Generates the reference clock for the Endpoint at the required frequency.
- Provides a PCI Express reset at start up.
For more details on the Root Port BFM, refer to the TestBench chapter of the Intel FPGA P-Tile Avalon® streaming IP for PCI Express User Guide.
Figure 19. Performance Design Example Simulation Testbench
The Performance design example simulation testbench is similar to the PIO design example simulation testbench. It issues Memory Write cycles to set up and trigger the Performance design example to issue 10 Memory Writes followed by 10 Memory Reads.