[PATCH 2/3] drm/amdgpu: only enable swiotlb alloc when need v2

get the max io mapping address of system memory to see if it is over our card accessing range. v2: move checking later Change-Id: Ibc38dbd34a20af5b4a4b1ed154c14e1c58aa4c55 Signed-off-by: Chunming Zhou Reviewed-by: Monk Liu Reviewed-by: Christian König

[PATCH 2/3] drm/amdgpu: only enable swiotlb alloc when need v2

get the max io mapping address of system memory to see if it is over our card accessing range. v2: move checking later Change-Id: Ibc38dbd34a20af5b4a4b1ed154c14e1c58aa4c55 Signed-off-by: Chunming Zhou Reviewed-by: Monk Liu ---