-- Original DMA request dma_request <= pcie_rx_buffer_full; -- Disabled DMA (hardcoded off) dma_request <= '0'; If you cannot remove the DMA engine, starve it. Program your PLD's Base Address Registers (BARs) to map to a tiny memory region (e.g., 4KB). Configure the PLD to reject any Memory Write or Read TLP (Transaction Layer Packet) that targets an address outside a specific, non-RAM range.
This requires an internal TLP filter in your PLD logic: how to disable dma on pld
Hardening Your System: How to Disable DMA on a PLD-Based PCIe Device -- Original DMA request dma_request <