Comment 14 for bug 2002467

Similar to the issue on upstream
https://gitlab.freedesktop.org/drm/amd/-/issues/2220

Compare what we backported and the kernel versions reported on the upstream bug, I feel like it's below commit introduce the regression

Could you try this test kernel to see if it helps, it only reverts the below commit.
https://people.canonical.com/~acelan/bugs/lp2002467/

commit d2c4c1569a7d7d5c8f75963bf2d62d7aeac30e2a
Author: Lijo Lazar <email address hidden>
Date: Fri Sep 30 10:43:08 2022 +0530

    drm/amdgpu: Remove ATC L2 access for MMHUB 2.1.x

    MMHUB 2.1.x versions don't have ATCL2. Remove accesses to ATCL2 registers.

    Since they are non-existing registers, read access will cause a
    'Completer Abort' and gets reported when AER is enabled with the below patch.
    Tagging with the patch so that this is backported along with it.

    v2: squash in uninitialized warning fix (Nathan Chancellor)

    Fixes: 8795e182b02d ("PCI/portdrv: Don't disable AER reporting in get_port_device_capability()")

    Signed-off-by: Lijo Lazar <email address hidden>
    Reviewed-by: Guchun Chen <email address hidden>
    Signed-off-by: Alex Deucher <email address hidden>
    Cc: <email address hidden>