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From 344005149244dd89368d1f2b845b07bf63f64307 Mon Sep 17 00:00:00 2001
From: Steven Price <steven.price@arm.com>
Date: Wed, 15 Jun 2022 16:48:30 +0100
Subject: drm/rockchip: Detach from ARM DMA domain in attach_device
Git-commit: 8490cad4dc4e2ee265ba9e12cd47bdfd6b9a3d34
Patch-mainline: v5.19-rc7
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

Since commit 1ea2a07a532b ("iommu: Add DMA ownership management
interfaces") the Rockchip display driver on the Firefly RK3288 fails to
initialise properly. This is because ARM DMA domain is still attached.

Let's follow the lead of exynos and tegra and add code to explicitly
remove the ARM domain before attaching a new one.

Fixes: 1ea2a07a532b ("iommu: Add DMA ownership management interfaces")
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Steven Price <steven.price@arm.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220615154830.555422-1-steven.price@arm.com
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
index 6ab046081946..913977cc5a32 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
@@ -23,6 +23,14 @@
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_vblank.h>
 
+#if defined(CONFIG_ARM_DMA_USE_IOMMU)
+#include <asm/dma-iommu.h>
+#else
+#define arm_iommu_detach_device(...)	({ })
+#define arm_iommu_release_mapping(...)	({ })
+#define to_dma_iommu_mapping(dev) NULL
+#endif
+
 #include "rockchip_drm_drv.h"
 #include "rockchip_drm_fb.h"
 #include "rockchip_drm_gem.h"
@@ -49,6 +57,15 @@ int rockchip_drm_dma_attach_device(struct drm_device *drm_dev,
 	if (!private->domain)
 		return 0;
 
+	if (IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU)) {
+		struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);
+
+		if (mapping) {
+			arm_iommu_detach_device(dev);
+			arm_iommu_release_mapping(mapping);
+		}
+	}
+
 	ret = iommu_attach_device(private->domain, dev);
 	if (ret) {
 		DRM_DEV_ERROR(dev, "Failed to attach iommu device\n");
-- 
2.38.1