Article ID: 000080850 Content Type: Troubleshooting Last Reviewed: 04/24/2019

Why does the Intel® Stratix® 10 Avalon®-MM Interface for PCIe* with DMA example design fail the link test and the DMA test when using the default selected BAR0?

Environment

  • Intel® Stratix® 10 FPGAs and SoC FPGAs
  • Intel® Quartus® Prime Pro Edition
  • Avalon-MM Intel® Stratix® 10 Hard IP for PCI Express
  • Avalon-MM Intel® Stratix® 10 Hard IP+ for PCI Express
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    Description

    When the internal DMA Descriptor Controller is enabled, the BAR0 Avalon®-MM master is not available for general-purpose usage. The DMA Descriptor Controller uses this BAR0 interface through which the host CPU programs in the descriptor table.

    The intel_fpga_pcie_link_test user application selects BAR0 as default when it's initially executed. If the user forgets to change to BAR2, which is where the onchip memory is attached, then both the link test and the DMA test will fail.

    Resolution

    The user must change to BAR2 before executing the link test and the DMA test.

    See the execution transcript of the intel_fpga_pcie_link_test user application below for how to change to BAR2.

     

    ~$ sudo ./intel_fpga_pcie_link_test

    *********************************************************

    Intel FPGA PCIe Link Test

    Version 2.0

    0: Automatically select a device

    1: Manually select a device

    *********************************************************

    > 0

    Opened a handle to BAR 0 of a device with BDF 0x1300

     

    *********************************************************

    0: Link test - 100 writes and reads

    1: Write memory space

    2: Read memory space

    3: Write configuration space

    4: Read configuration space

    5: Change BAR

    6: Change device

    7: Enable SRIOV

    8: Do a link test for every enabled virtual function

        belonging to the current device

    9: Perform DMA

    10: Quit program

    *********************************************************

    > 5

    Changing BAR...

    Enter BAR number (-1 for none):

    > 2

    Successfully changed BAR!

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