[Intel-gfx] [PATCH] drm/i915: Update dma-attributes for our sg DMA

[Matthew Auld]

On 06/07/2020 23:43, Chris Wilson wrote:
> Looking through the attributes for DMA mappings, it appears that by
> default dma_map_sg will try and create a kernel accessible map of the
> page. We never access this, as we either have a struct page already or
> an iomap, so we can request that the dma mapper does not create one.
> Without a kernel map in place, one presumes the rest of the memory
> control attributes do not apply. We also explicitly control the caches
> around the mappings, so we can ask it not to bother synchronising itself.
> 
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Matthew Auld <matthew.auld at intel.com>
Reviewed-by: Matthew Auld <matthew.auld at intel.com>