[PATCH] drm/exynos: allocate non-contigous buffers when iommu is enabled

[Rahul Sharma]

From: Rahul Sharma <Rahul.Sharma at samsung.com>

Allow to allocate non-contigous buffers when iommu is enabled.
Currently, it tries to allocates contigous buffer which consistently
fail for large buffers and then fall back to non contigous. Apart
from being slow, this implementation is also very noisy and fills
the screen with alloc fail logs.

Change-Id: I523e95aa308122ed2edc55e065ae6eb8be996541
Signed-off-by: Rahul Sharma <Rahul.Sharma at samsung.com>
---
 drivers/gpu/drm/exynos/exynos_drm_gem.c |   22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c
index 5d88924..7136945 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_gem.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c
@@ -624,22 +624,20 @@ int exynos_drm_gem_dumb_create(struct drm_file *file_priv,
 	args->pitch = args->width * ((args->bpp + 7) / 8);
 	args->size = args->pitch * args->height;
 
-	exynos_gem_obj = exynos_drm_gem_create(dev, EXYNOS_BO_CONTIG |
-						EXYNOS_BO_WC, args->size);
-	/*
-	 * If physically contiguous memory allocation fails and if IOMMU is
-	 * supported then try to get buffer from non physically contiguous
-	 * memory area.
-	 */
-	if (IS_ERR(exynos_gem_obj) && is_drm_iommu_supported(dev)) {
-		dev_warn(dev->dev, "contiguous FB allocation failed, falling back to non-contiguous\n");
+	if (is_drm_iommu_supported(dev)) {
+		exynos_gem_obj = exynos_drm_gem_create(dev,
+			EXYNOS_BO_NONCONTIG | EXYNOS_BO_WC,
+			args->size);
+	} else {
 		exynos_gem_obj = exynos_drm_gem_create(dev,
-					EXYNOS_BO_NONCONTIG | EXYNOS_BO_WC,
-					args->size);
+			EXYNOS_BO_CONTIG | EXYNOS_BO_WC,
+			args->size);
 	}
 
-	if (IS_ERR(exynos_gem_obj))
+	if (IS_ERR(exynos_gem_obj)) {
+		dev_warn(dev->dev, "FB allocation failed.\n");
 		return PTR_ERR(exynos_gem_obj);
+	}
 
 	ret = exynos_drm_gem_handle_create(&exynos_gem_obj->base, file_priv,
 			&args->handle);
-- 
1.7.9.5