[PATCH 4.9 037/148] drm/exynos: gem: Drop NONCONTIG flag for buffers allocated without IOMMU

Greg Kroah-Hartman
2017-12-12T12:58:10Z

From: Marek Szyprowski <m.szyprowski@samsung.com>

commit 120a264f9c2782682027d931d83dcbd22e01da80 upstream.

When no IOMMU is available, all GEM buffers allocated by Exynos DRM driver
are contiguous, because of the underlying dma_alloc_attrs() function
provides only such buffers. In such case it makes no sense to keep
BO_NONCONTIG flag for the allocated GEM buffers. This allows to avoid
failures for buffer contiguity checks in the subsequent operations on GEM
objects.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpu/drm/exynos/exynos_drm_gem.c | 9 +++++++++
1 file changed, 9 insertions(+)

--- a/drivers/gpu/drm/exynos/exynos_drm_gem.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c
@@ -246,6 +246,15 @@ struct exynos_drm_gem *exynos_drm_gem_cr
if (IS_ERR(exynos_gem))
return exynos_gem;

+ if (!is_drm_iommu_supported(dev) && (flags & EXYNOS_BO_NONCONTIG)) {
+ /*
+ * when no IOMMU is available, all allocated buffers are
+ * contiguous anyway, so drop EXYNOS_BO_NONCONTIG flag
+ */
+ flags &= ~EXYNOS_BO_NONCONTIG;
+ DRM_WARN("Non-contiguous allocation is not supported without IOMMU, falling back to contiguous buffer\n");
+ }
+
/* set memory type and cache attribute from user side. */
exynos_gem->flags = flags;