amd-iommu: can't boot with amdgpu, AMD-Vi: Completion-Wait loop timed out

[Nath, Arindam]

>-----Original Message-----
>From: 'joro at 8bytes.org' [mailto:joro at 8bytes.org]
>Sent: Tuesday, March 21, 2017 9:41 PM
>To: Deucher, Alexander
>Cc: Alex Deucher; Daniel Drake; Chris Chiu; amd-gfx at lists.freedesktop.org;
>Nath, Arindam; iommu at lists.linux-foundation.org; Suthikulpanit, Suravee;
>Linux Upstreaming Team
>Subject: Re: amd-iommu: can't boot with amdgpu, AMD-Vi: Completion-Wait
>loop timed out
>
>On Tue, Mar 21, 2017 at 04:01:53PM +0000, Deucher, Alexander wrote:
>> It seems to only affect Stoney systems, but not others (Carrizo,
>> Bristol, etc.).  Maybe we could just disable it on Stoney until we
>> root cause it.
>
>Completion-wait loop timeouts indicate something is seriously wrong. How
>can I detect whether I am running on a 'Stoney' system?
>
>Other question, a shot into the dark, does the GPU on these systems have
>ATS? Probably yes, as they are likely HSA compatible.

The GPU on Stoney supports ATS.

Thanks,
Arindam

>
>
>	Joerg