Re: thunderbolt: AMD Phoenix USB4 host advertises Gen3 Support=0 in SB LINK_CONF with TB5 device, link stuck at Gen2

[Mika Westerberg <mika.westerberg@linux.intel.com>]

Hi,

On Mon, Nov 09, 2026 at 11:25:45AM +0000, James Taylor wrote:
> Hi Mika,
> 
> On Mon, Nov 09, 2026 at 12:18:52PM +0100, Mika Westerberg wrote:
> > Please use tbdump from tbtools [1]. It knows the registers. Something like
> > this:
> >
> > https://github.com/intel/tbtools/wiki/Useful-Commands#dump-lane-adapter-capability-for-current-link-capabilities-and-status
> 
> Thanks, here it is (tbtools 0.8.0). Domain 1 route 0 is the AMD host
> router, route 2 is the DEG2 (JHL9480). Both lane adapters on each side
> are included, followed by tbadapters for reference.

In your command line:

[    0.000000] Command line: initrd=\EFI\nixos\c18phgd1m2qpc2g72pz14fg9h9i38j6w-initrd-linux-7.2.15-initrd.efi init=/nix/store/2m5ckvjrfdbcxrfpklc7rg16jwi11spa-nixos-system-nyx-26.11.20261106.4fe25e1/init usb-storage.quirks=0bc2:3343:u thunderbolt.host_reset=0 pcie_aspm=off nohibernate root=fstab loglevel=4 lsm=landlock,yama,bpf

Please drop thunderbolt.host_reset=0 and pcie_aspm=off. The later disables
much more than just ASPM so it may affect everything. Once you have done
that please take another dmesg (and check also the link registers via
tbdump).