Occasionally `14160000.pcie: Phy link never came up`

Could you go to kernel/nvidia/drivers/pci/dwc/pcie-tegra.c and directly hardcoded the init_speed variable to 1 and see if that works?

I find that CONFIG_ARCH_TEGRA_19x_SOC is not enabled and it cannot be enabled through menuconfig.

It seems that we use kernel-5.10/drivers/pci/controller/pci-tegra.c instead of kernel/nvidia/drivers/pci/dwc/pcie-tegra.c

Hi WayneWWW! If the above is failed to work. I wonder that how to use setpci command to operate registers and upgrade the pcie from gen1 to gen3.