From 7d7bb790aced3b1b8550b74e02fdfc001d044bee Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Wed, 22 Oct 2025 19:19:48 +0300 Subject: [PATCH] drm/rockchip: Set VOP for the DRM DMA device Use VOP for DMA operations performed by DRM core. Rockchip DRM driver is backed by a virtual device that isn't IOMMU-capable, while VOP is the actual display controller device backed by IOMMU. Fixes "swiotlb buffer is full" warning messages originated from GEM prime code paths. Note, that backporting is non-trivial as this depends on commit 143ec8d3f9396 ("drm/prime: Support dedicated DMA device for dma-buf imports"), which landed in v6.16 and commit 421be3ee36a4 ("drm/rockchip: Refactor IOMMU initialisation"), which landed in v5.19. Reported-by: Daniel Stone Fixes: 2048e3286f34 ("drm: rockchip: Add basic drm driver") Cc: stable@vger.kernel.org # v6.16+ Reviewed-by: Sebastian Reichel Signed-off-by: Dmitry Osipenko Tested-by: Cristian Ciocaltea Signed-off-by: Heiko Stuebner Link: https://lore.kernel.org/r/20251022161948.199731-1-dmitry.osipenko@collabora.com --- drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c index c5c6e2b5772d8..3099408e9d050 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c @@ -97,6 +97,9 @@ void rockchip_drm_dma_init_device(struct drm_device *drm_dev, private->iommu_dev = ERR_PTR(-ENODEV); else if (!private->iommu_dev) private->iommu_dev = dev; + + if (!IS_ERR(private->iommu_dev)) + drm_dev_set_dma_dev(drm_dev, private->iommu_dev); } static int rockchip_drm_init_iommu(struct drm_device *drm_dev) -- 2.47.3