Merge tag 'exynos-drm-fixes-for-v4.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/daeinki/drm-exynos into drm-fixes

Use default iommu domain instead of fake one
- This patch makes it to reuse default IOMMU domain instead of
  allocating a fake IOMMU domain, and allows some design changes
  for enhancement of IOMMU framework[1] without breaking Exynos DRM.

[1] https://www.spinics.net/lists/arm-kernel/msg676098.html

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Inki Dae <inki.dae@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1538360696-23579-1-git-send-email-inki.dae@samsung.com

1 files changed, 6 insertions, 28 deletions

diff --git a/drivers/gpu/drm/exynos/exynos_drm_iommu.h b/drivers/gpu/drm/exynos/exynos_drm_iommu.h
index 87f6b5672e11..797d9ee5f15a 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_iommu.h
+++ b/drivers/gpu/drm/exynos/exynos_drm_iommu.h
@@ -55,37 +55,12 @@ static inline void __exynos_iommu_detach(struct exynos_drm_private *priv,
 static inline int __exynos_iommu_create_mapping(struct exynos_drm_private *priv,
                                         unsigned long start, unsigned long size)
 {
-        struct iommu_domain *domain;
-        int ret;
-
-        domain = iommu_domain_alloc(priv->dma_dev->bus);
-        if (!domain)
-                return -ENOMEM;
-
-        ret = iommu_get_dma_cookie(domain);
-        if (ret)
-                goto free_domain;
-
-        ret = iommu_dma_init_domain(domain, start, size, NULL);
-        if (ret)
-                goto put_cookie;
-
-        priv->mapping = domain;
+        priv->mapping = iommu_get_domain_for_dev(priv->dma_dev);
         return 0;
-
-put_cookie:
-        iommu_put_dma_cookie(domain);
-free_domain:
-        iommu_domain_free(domain);
-        return ret;
 }
 
 static inline void __exynos_iommu_release_mapping(struct exynos_drm_private *priv)
 {
-        struct iommu_domain *domain = priv->mapping;
-
-        iommu_put_dma_cookie(domain);
-        iommu_domain_free(domain);
         priv->mapping = NULL;
 }
 
@@ -94,7 +69,9 @@ static inline int __exynos_iommu_attach(struct exynos_drm_private *priv,
 {
         struct iommu_domain *domain = priv->mapping;
 
-        return iommu_attach_device(domain, dev);
+        if (dev != priv->dma_dev)
+                return iommu_attach_device(domain, dev);
+        return 0;
 }
 
 static inline void __exynos_iommu_detach(struct exynos_drm_private *priv,
@@ -102,7 +79,8 @@ static inline void __exynos_iommu_detach(struct exynos_drm_private *priv,
 {
         struct iommu_domain *domain = priv->mapping;
 
-        iommu_detach_device(domain, dev);
+        if (dev != priv->dma_dev)
+                iommu_detach_device(domain, dev);
 }
 #else
 #error Unsupported architecture and IOMMU/DMA-mapping glue code