gpu: host1x: Detach Host1x from IOMMU DMA domain on arm32

Host1x is getting attached to an implicit IOMMU DMA domain if
CONFIG_ARM_DMA_USE_IOMMU=y. Since Host1x driver manages IOMMU by
itself, Host1x device must be detached from the implicit domain using
arch-specific IOMMU-API.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

1 files changed, 12 insertions, 1 deletions

diff --git a/drivers/gpu/host1x/dev.c b/drivers/gpu/host1x/dev.c
index d88073e7d22d..de6bc4e7fa23 100644
--- a/drivers/gpu/host1x/dev.c
+++ b/drivers/gpu/host1x/dev.c
@@ -29,6 +29,10 @@
 #include <trace/events/host1x.h>
 #undef CREATE_TRACE_POINTS
 
+#if IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU)
+#include <asm/dma-iommu.h>
+#endif
+
 #include "bus.h"
 #include "channel.h"
 #include "debug.h"
@@ -217,7 +221,14 @@ static int host1x_probe(struct platform_device *pdev)
                 dev_err(&pdev->dev, "failed to get reset: %d\n", err);
                 return err;
         }
-
+#if IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU)
+        if (host->dev->archdata.mapping) {
+                struct dma_iommu_mapping *mapping =
+                                to_dma_iommu_mapping(host->dev);
+                arm_iommu_detach_device(host->dev);
+                arm_iommu_release_mapping(mapping);
+        }
+#endif
         if (IS_ENABLED(CONFIG_TEGRA_HOST1X_FIREWALL))
                 goto skip_iommu;