The case of CONFIG_ARM_DMA_USE_IOMMU=y was found to be broken for DRM driver. Add back the workaround using arm_iommu_detach_device() as a temporary solution.
Cc: stable@vger.kernel.org Fixes: fa6661b7aa0b ("drm/tegra: Optionally attach clients to the IOMMU") Signed-off-by: Dmitry Osipenko digetx@gmail.com --- drivers/gpu/drm/tegra/drm.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+)
diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c index 90709c38c993..a949cb678e08 100644 --- a/drivers/gpu/drm/tegra/drm.c +++ b/drivers/gpu/drm/tegra/drm.c @@ -20,6 +20,10 @@ #include <drm/drm_prime.h> #include <drm/drm_vblank.h>
+#if IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU) +#include <asm/dma-iommu.h> +#endif + #include "drm.h" #include "gem.h"
@@ -909,6 +913,17 @@ int host1x_client_iommu_attach(struct host1x_client *client) struct iommu_group *group = NULL; int err;
+#if IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU) + if (client->dev->archdata.mapping) { + struct dma_iommu_mapping *mapping = + to_dma_iommu_mapping(client->dev); + arm_iommu_detach_device(client->dev); + arm_iommu_release_mapping(mapping); + + domain = iommu_get_domain_for_dev(client->dev); + } +#endif + /* * If the host1x client is already attached to an IOMMU domain that is * not the shared IOMMU domain, don't try to attach it to a different