Hi all, I am not certain why this happens, but when IO bar is assigned on Thunderbolt, the amdgpu init fails: [drm:atom_op_jump [amdgpu]] *ERROR* atombios stuck in loop for more than 20secs aborting [drm:amdgpu_atom_execute_table_locked [amdgpu]] *ERROR* atombios stuck executing B456 (len 304, WS 4, PS 0) @ 0xB51B [drm:amdgpu_atom_execute_table_locked [amdgpu]] *ERROR* atombios stuck executing B104 (len 183, WS 0, PS 8) @ 0xB17E amdgpu 0000:08:00.0: amdgpu: gpu post error! amdgpu 0000:08:00.0: amdgpu: Fatal error during GPU init amdgpu: probe of 0000:08:00.0 failed with error -22 It seems to happen mostly when BIOS-assisted PCI enumeration is used (older Thunderbolt systems). I cannot rule it out with native enumeration, but generally native enumeration works, as the IO BAR is not assigned, due to limited IO resources. This patch is a simple fix against v5.12-rc2. I have experienced this issue for a long time, and have finally decided to do something about it. I do not see a downside to using MMIO, which is required to be assigned. Kind regards, Nicholas Johnson Nicholas Johnson (1): amdgpu: use MMIO to init atombios if device is Thunderbolt / USB4 attached drivers/gpu/drm/amd/amdgpu/amdgpu_atombios.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) -- 2.30.2 _______________________________________________ amd-gfx mailing list amd-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/amd-gfx