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Subject: Re: AMD graphics performance regression in 4.15 and later
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From: Jean-Marc Valin <jmvalin@mozilla.com>
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Date: Mon, 9 Apr 2018 11:17:43 -0400
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On 04/09/2018 05:42 AM, Christian König wrote:
> Backporting all the detection logic is to invasive, but you could just
> go into drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c and forcefull use the
> other code path.
> 
> Just look out for "#ifdef CONFIG_SWIOTLB" checks and disable those.

Do you mean just taking the 4.15 code as is and replacing
"#ifdef CONFIG_SWIOTLB" with "#if 0" in
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c or are you talking about using a
different version of drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c ?

	Jean-Marc