The AXI4 PCIe sub-system provides full bridge functionality between the AXI4 architecture and the PCIe network. The sub-system is composed of the PCIe core, the GT interface and the AXI4 interface.

After removing the VL805 QFN package and soldering in the bridge PCB, [Zak] confirmed that everything was hooked up properly and attempted to use the Raspberry Pi 4 with a PCIe extender.

Getting that first PCIe port added to the Pi 4 is already fairly ... and one that seemed especially important: “devices behind bridge are unusable because [bus 02] cannot be assigned for them“.

This PCI to AMBA AHB Host Bridge IP core enables data transfers between an AMBA® AHB host processor bus system and PCI bus based devices. The bridge enables higher utilization of the bus’ available ...