xavier pci clock

Hi NV people

how did i modify pcie clock ?

By “gen.2”, if you meant, only the max speed supported by Gen-2 i.e. 5 GT/s, then, you can edit the device tree and set “nvidia,max-speed” property to ‘2’ (by default it is set to 4)
If you are referring to making Xavier’s PCIe root port to work strictly as a Gen-2 spec device, then I’m afraid it is not possible. Although root port is a Gen-4 compliant device, it can work with endpoints designed to comply with Gen-2 version of the spec as well.