drm/msm: Attach the IOMMU device during initialization

Everywhere an IOMMU object is created by msm_gpu_create_address_space
the IOMMU device is attached immediately after. Instead of carrying around
the infrastructure to do the attach from the device specific code do it
directly in the msm_iommu_init() function. This gets it out of the way for
more aggressive cleanups that follow.

Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
[squash in rebase fixups and fix for unused fxn]
Signed-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/adreno/a6xx_gmu.c

@@ -1114,7 +1114,6 @@ static int a6xx_gmu_memory_alloc(struct a6xx_gmu *gmu, struct a6xx_gmu_bo *bo,
 static int a6xx_gmu_memory_probe(struct a6xx_gmu *gmu)
 {
 	struct iommu_domain *domain;
-	int ret;
 
 	domain = iommu_domain_alloc(&platform_bus_type);
 	if (!domain)
@@ -1129,12 +1128,6 @@ static int a6xx_gmu_memory_probe(struct a6xx_gmu *gmu)
 		return PTR_ERR(gmu->aspace);
 	}
 
-	ret = gmu->aspace->mmu->funcs->attach(gmu->aspace->mmu);
-	if (ret) {
-		msm_gem_address_space_put(gmu->aspace);
-		return ret;
-	}
-
 	return 0;
 }
 

drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c

@@ -794,7 +794,6 @@ static int _dpu_kms_mmu_init(struct dpu_kms *dpu_kms)
 {
 	struct iommu_domain *domain;
 	struct msm_gem_address_space *aspace;
-	int ret;
 
 	domain = iommu_domain_alloc(&platform_bus_type);
 	if (!domain)
@@ -810,13 +809,6 @@ static int _dpu_kms_mmu_init(struct dpu_kms *dpu_kms)
 		return PTR_ERR(aspace);
 	}
 
-	ret = aspace->mmu->funcs->attach(aspace->mmu);
-	if (ret) {
-		DPU_ERROR("failed to attach iommu %d\n", ret);
-		msm_gem_address_space_put(aspace);
-		return ret;
-	}
-
 	dpu_kms->base.aspace = aspace;
 	return 0;
 }

drivers/gpu/drm/msm/disp/mdp4/mdp4_kms.c

@@ -518,10 +518,6 @@ struct msm_kms *mdp4_kms_init(struct drm_device *dev)
 		}
 
 		kms->aspace = aspace;
-
-		ret = aspace->mmu->funcs->attach(aspace->mmu);
-		if (ret)
-			goto fail;
 	} else {
 		DRM_DEV_INFO(dev->dev, "no iommu, fallback to phys "
 				"contig buffers for scanout\n");

drivers/gpu/drm/msm/disp/mdp5/mdp5_kms.c

@@ -644,13 +644,6 @@ struct msm_kms *mdp5_kms_init(struct drm_device *dev)
 		}
 
 		kms->aspace = aspace;
-
-		ret = aspace->mmu->funcs->attach(aspace->mmu);
-		if (ret) {
-			DRM_DEV_ERROR(&pdev->dev, "failed to attach iommu: %d\n",
-				ret);
-			goto fail;
-		}
 	} else {
 		DRM_DEV_INFO(&pdev->dev,
 			 "no iommu, fallback to phys contig buffers for scanout\n");

drivers/gpu/drm/msm/msm_gem_vma.c

@@ -133,8 +133,8 @@ msm_gem_address_space_create(struct device *dev, struct iommu_domain *domain,
 		const char *name)
 {
 	struct msm_gem_address_space *aspace;
-	u64 size = domain->geometry.aperture_end -
-		domain->geometry.aperture_start;
+	u64 start = domain->geometry.aperture_start;
+	u64 size = domain->geometry.aperture_end - start;
 
 	aspace = kzalloc(sizeof(*aspace), GFP_KERNEL);
 	if (!aspace)
@@ -143,9 +143,18 @@ msm_gem_address_space_create(struct device *dev, struct iommu_domain *domain,
 	spin_lock_init(&aspace->lock);
 	aspace->name = name;
 	aspace->mmu = msm_iommu_new(dev, domain);
+	if (IS_ERR(aspace->mmu)) {
+		int ret = PTR_ERR(aspace->mmu);
 
-	drm_mm_init(&aspace->mm, (domain->geometry.aperture_start >> PAGE_SHIFT),
-		size >> PAGE_SHIFT);
+		kfree(aspace);
+		return ERR_PTR(ret);
+	}
+
+	/*
+	 * Attaching the IOMMU device changes the aperture values so use the
+	 * cached values instead
+	 */
+	drm_mm_init(&aspace->mm, start >> PAGE_SHIFT, size >> PAGE_SHIFT);
 
 	kref_init(&aspace->kref);
 
@@ -166,6 +175,12 @@ msm_gem_address_space_create_a2xx(struct device *dev, struct msm_gpu *gpu,
 	spin_lock_init(&aspace->lock);
 	aspace->name = name;
 	aspace->mmu = msm_gpummu_new(dev, gpu);
+	if (IS_ERR(aspace->mmu)) {
+		int ret = PTR_ERR(aspace->mmu);
+
+		kfree(aspace);
+		return ERR_PTR(ret);
+	}
 
 	drm_mm_init(&aspace->mm, (va_start >> PAGE_SHIFT),
 		size >> PAGE_SHIFT);

drivers/gpu/drm/msm/msm_gpu.c

@@ -826,7 +826,6 @@ msm_gpu_create_address_space(struct msm_gpu *gpu, struct platform_device *pdev,
 		uint64_t va_start, uint64_t va_end)
 {
 	struct msm_gem_address_space *aspace;
-	int ret;
 
 	/*
 	 * Setup IOMMU.. eventually we will (I think) do this once per context
@@ -851,17 +850,9 @@ msm_gpu_create_address_space(struct msm_gpu *gpu, struct platform_device *pdev,
 			va_start, va_end);
 	}
 
-	if (IS_ERR(aspace)) {
+	if (IS_ERR(aspace))
 		DRM_DEV_ERROR(gpu->dev->dev, "failed to init mmu: %ld\n",
 			PTR_ERR(aspace));
-		return ERR_CAST(aspace);
-	}
-
-	ret = aspace->mmu->funcs->attach(aspace->mmu);
-	if (ret) {
-		msm_gem_address_space_put(aspace);
-		return ERR_PTR(ret);
-	}
 
 	return aspace;
 }

drivers/gpu/drm/msm/msm_gpummu.c

@@ -21,11 +21,6 @@ struct msm_gpummu {
 #define GPUMMU_PAGE_SIZE SZ_4K
 #define TABLE_SIZE (sizeof(uint32_t) * GPUMMU_VA_RANGE / GPUMMU_PAGE_SIZE)
 
-static int msm_gpummu_attach(struct msm_mmu *mmu)
-{
-	return 0;
-}
-
 static void msm_gpummu_detach(struct msm_mmu *mmu)
 {
 }
@@ -85,7 +80,6 @@ static void msm_gpummu_destroy(struct msm_mmu *mmu)
 }
 
 static const struct msm_mmu_funcs funcs = {
-		.attach = msm_gpummu_attach,
 		.detach = msm_gpummu_detach,
 		.map = msm_gpummu_map,
 		.unmap = msm_gpummu_unmap,

drivers/gpu/drm/msm/msm_iommu.c

@@ -23,13 +23,6 @@ static int msm_fault_handler(struct iommu_domain *domain, struct device *dev,
 	return 0;
 }
 
-static int msm_iommu_attach(struct msm_mmu *mmu)
-{
-	struct msm_iommu *iommu = to_msm_iommu(mmu);
-
-	return iommu_attach_device(iommu->domain, mmu->dev);
-}
-
 static void msm_iommu_detach(struct msm_mmu *mmu)
 {
 	struct msm_iommu *iommu = to_msm_iommu(mmu);
@@ -66,7 +59,6 @@ static void msm_iommu_destroy(struct msm_mmu *mmu)
 }
 
 static const struct msm_mmu_funcs funcs = {
-		.attach = msm_iommu_attach,
 		.detach = msm_iommu_detach,
 		.map = msm_iommu_map,
 		.unmap = msm_iommu_unmap,
@@ -76,6 +68,7 @@ static const struct msm_mmu_funcs funcs = {
 struct msm_mmu *msm_iommu_new(struct device *dev, struct iommu_domain *domain)
 {
 	struct msm_iommu *iommu;
+	int ret;
 
 	iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
 	if (!iommu)
@@ -85,5 +78,11 @@ struct msm_mmu *msm_iommu_new(struct device *dev, struct iommu_domain *domain)
 	msm_mmu_init(&iommu->base, dev, &funcs);
 	iommu_set_fault_handler(domain, msm_fault_handler, iommu);
 
+	ret = iommu_attach_device(iommu->domain, dev);
+	if (ret) {
+		kfree(iommu);
+		return ERR_PTR(ret);
+	}
+
 	return &iommu->base;
 }

drivers/gpu/drm/msm/msm_mmu.h

@@ -10,7 +10,6 @@
 #include <linux/iommu.h>
 
 struct msm_mmu_funcs {
-	int (*attach)(struct msm_mmu *mmu);
 	void (*detach)(struct msm_mmu *mmu);
 	int (*map)(struct msm_mmu *mmu, uint64_t iova, struct sg_table *sgt,
 			unsigned len, int prot);