I'm not sure why you would need ACPI or a device tree to be involved. ACPI and device tree are ways to tell the OS about devices that do not have a native enumeration protocol. PCI devices (like the programmed FPGA) do support native enumeration, so generally we don't need ACPI or device tree descriptions of them. PCI host bridges have a CPU-specific bus on the upstream side and a PCI bus on the downstream side, so they are not themselves PCI devices, and we do need ACPI or device tree descriptions for them. If you have something that doesn't work like you expect, can you post a complete dmesg log and any user commands you're using to program the FPGA? Bjorn