Hardware 3D acceleration doesn't work anymore with the latest git kernel

[Michel Dänzer]

On 2017-11-24 03:29 PM, Christian Zigotzky wrote:
> Hi All,
> 
> I bisected today and the first bad commit is:
> a4dec819c8bba6365eb893a4ca88db4dd1210110 (drm/ttm: Add helper functions
> to populate/map in one call (v2)) [1]

It can't really be that commit, since it just adds functions but doesn't
hook them up anywhere. Presumably it's commit
f7871fd19389c5f64f625a4389675d0740f0dfe4 ("drm/radeon: use new TTM
populate/dma map helper functions") instead, which makes the radeon
driver rely on ttm_populate_and_map_pages, which is just a stub
returning -ENOMEM when neither CONFIG_SWIOTLB nor CONFIG_INTEL_IOMMU is
enabled.

I can see two possible solutions:

1. Make ttm_populate_and_map_pages and ttm_unmap_and_unpopulate_pages
   work without SWIOTLB / INTEL_IOMMU as well.

2. Make the drivers work without ttm_populate_and_map_pages and
   ttm_unmap_and_unpopulate_pages again in that case.


Solution 1 would be preferable.


-- 
Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer