Building XilinxVariumC1100PrbsTester

The PrbsTester target is a second XilinxVariumC1100 application. Unlike XilinxVariumC1100DmaLoopback (which wires DMA-in to DMA-out for a host-side soak test), PrbsTester instantiates firmware/common/PrbsTester in-hardware, generating PRBS streams on the FPGA itself and validating the DMA path independent of any host-side traffic generator.

The build flow is identical to First Build — XilinxVariumC1100DmaLoopback — the differences are entirely inside the target’s ruckus.tcl.

Prerequisites

Same as First Build — XilinxVariumC1100DmaLoopback: git-lfs, recursively initialised submodules, Vivado 2024.2+ on PATH (Vivado 2025.2 at SLAC).

Build

source /sdf/group/faders/tools/xilinx/2025.2/Vivado/2025.2/settings64.sh
cd firmware/targets/XilinxVariumC1100/XilinxVariumC1100PrbsTester
make

What Differs From DmaLoopback

The PrbsTester ruckus.tcl (firmware/targets/XilinxVariumC1100/XilinxVariumC1100PrbsTester/ruckus.tcl) pulls in two pieces of RTL on top of what DmaLoopback uses:

loadRuckusTcl $::env(PROJ_DIR)/../../../submodules/axi-pcie-core/hardware/XilinxVariumC1100/ddr
loadRuckusTcl $::env(PROJ_DIR)/../../../common/PrbsTester

The first pulls in the board’s HBM DMA buffer support; the second pulls in the in-hardware PRBS generator/checker application (firmware/common/PrbsTester/rtl/PrbsLane.vhd).

The Makefile is otherwise identical — same PRJ_PART = XCU55N-FSVH2892-2L-E, same PARALLEL_SYNTH = 8, same target: prom.

Build Artefacts

Output files appear in:

firmware/targets/XilinxVariumC1100/XilinxVariumC1100PrbsTester/images/
    XilinxVariumC1100PrbsTester-<version>.bit
    XilinxVariumC1100PrbsTester-<version>.mcs

Same expected critical warnings as DmaLoopback (the PCIe PHY black-box constraints) — see First Build — XilinxVariumC1100DmaLoopback for explanations.

Exercising the PRBS Tester

After flashing the board and rescanning the PCIe bus, drive the in-hardware PRBS engine from Python with software/scripts/PrbsTesting.py — see Run the PGP Test Suite for the operating recipe.