[PATCH 2/8] drm/tegra: Allocate BOs from lower 4G when without IOMMU

[Mikko Perttunen]

On 64-bit Tegras, buffer object memory allocation may
return memory above 4G that units behind Host1x cannot
access. Add the GFP_DMA flag to these allocation when
IOMMU is not enabled to ensure units can always access
BO memory.

Signed-off-by: Mikko Perttunen <mperttunen at nvidia.com>
---
 drivers/gpu/drm/tegra/gem.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c
index 19bf9cd..e36e6c5 100644
--- a/drivers/gpu/drm/tegra/gem.c
+++ b/drivers/gpu/drm/tegra/gem.c
@@ -233,7 +233,7 @@ static int tegra_bo_alloc(struct drm_device *drm, struct tegra_bo *bo)
 		size_t size = bo->gem.size;
 
 		bo->vaddr = dma_alloc_wc(drm->dev, size, &bo->paddr,
-					 GFP_KERNEL | __GFP_NOWARN);
+					 GFP_KERNEL | GFP_DMA | __GFP_NOWARN);
 		if (!bo->vaddr) {
 			dev_err(drm->dev,
 				"failed to allocate buffer of size %zu\n",
-- 
2.10.2