data link layer , CDC synchronizers, Virtual Channels, PCIe compliance testing, PnR constraints, Transaction Layer, SerDes PHY, multi-clock-domain design, TLP structure, PCIe PHY-MAC interface protocols, PCIe architecture, clock crossing, SystemVerilog RTL, host software driver interaction, flow control, reset sequencing, CXL 1.1 2.0 or 3.0 protocol, async FIFO, Physical Layer, SR-IOV, PCI-SIG certification process, PCIe power management, error handling, multi-function device configuration