drm/msm/a6xx: Create an A6XX GPU specific address space

A6XX GPUs have support for last level cache(LLC) also known
as system cache and need to set the bus attributes to
use it. Currently we use a generic adreno iommu address space
implementation which are also used by older GPU generations
which do not have LLC and might introduce issues accidentally
and is not clean in a way that anymore additions of GPUs
supporting LLC would have to be guarded under ifdefs. So keep
the generic code separate and make the address space creation
A6XX specific. We also have a helper to set the llc attributes
so that if the newer GPU generations do support them, we can
use it instead of open coding domain attribute setting for each
GPU.
Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/adreno/a6xx_gpu.c

@@ -1244,6 +1244,50 @@ static unsigned long a6xx_gpu_busy(struct msm_gpu *gpu)
 	return (unsigned long)busy_time;
 }
 
+static struct msm_gem_address_space *
+a6xx_create_address_space(struct msm_gpu *gpu, struct platform_device *pdev)
+{
+	struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
+	struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu);
+	struct iommu_domain *iommu;
+	struct msm_mmu *mmu;
+	struct msm_gem_address_space *aspace;
+	u64 start, size;
+
+	iommu = iommu_domain_alloc(&platform_bus_type);
+	if (!iommu)
+		return NULL;
+
+	/*
+	 * This allows GPU to set the bus attributes required to use system
+	 * cache on behalf of the iommu page table walker.
+	 */
+	if (!IS_ERR_OR_NULL(a6xx_gpu->htw_llc_slice))
+		adreno_set_llc_attributes(iommu);
+
+	mmu = msm_iommu_new(&pdev->dev, iommu);
+	if (IS_ERR(mmu)) {
+		iommu_domain_free(iommu);
+		return ERR_CAST(mmu);
+	}
+
+	/*
+	 * Use the aperture start or SZ_16M, whichever is greater. This will
+	 * ensure that we align with the allocated pagetable range while still
+	 * allowing room in the lower 32 bits for GMEM and whatnot
+	 */
+	start = max_t(u64, SZ_16M, iommu->geometry.aperture_start);
+	size = iommu->geometry.aperture_end - start + 1;
+
+	aspace = msm_gem_address_space_create(mmu, "gpu",
+		start & GENMASK_ULL(48, 0), size);
+
+	if (IS_ERR(aspace) && !IS_ERR(mmu))
+		mmu->funcs->destroy(mmu);
+
+	return aspace;
+}
+
 static struct msm_gem_address_space *
 a6xx_create_private_address_space(struct msm_gpu *gpu)
 {
@@ -1362,7 +1406,7 @@ static const struct adreno_gpu_funcs funcs = {
 		.gpu_state_get = a6xx_gpu_state_get,
 		.gpu_state_put = a6xx_gpu_state_put,
 #endif
-		.create_address_space = adreno_iommu_create_address_space,
+		.create_address_space = a6xx_create_address_space,
 		.create_private_address_space = a6xx_create_private_address_space,
 		.get_rptr = a6xx_get_rptr,
 	},

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

@@ -186,11 +186,18 @@ int adreno_zap_shader_load(struct msm_gpu *gpu, u32 pasid)
 	return zap_shader_load_mdt(gpu, adreno_gpu->info->zapfw, pasid);
 }
 
+void adreno_set_llc_attributes(struct iommu_domain *iommu)
+{
+	struct io_pgtable_domain_attr pgtbl_cfg;
+
+	pgtbl_cfg.quirks = IO_PGTABLE_QUIRK_ARM_OUTER_WBWA;
+	iommu_domain_set_attr(iommu, DOMAIN_ATTR_IO_PGTABLE_CFG, &pgtbl_cfg);
+}
+
 struct msm_gem_address_space *
 adreno_iommu_create_address_space(struct msm_gpu *gpu,
 		struct platform_device *pdev)
 {
-	struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
 	struct iommu_domain *iommu;
 	struct msm_mmu *mmu;
 	struct msm_gem_address_space *aspace;
@@ -200,20 +207,6 @@ adreno_iommu_create_address_space(struct msm_gpu *gpu,
 	if (!iommu)
 		return NULL;
 
-	if (adreno_is_a6xx(adreno_gpu)) {
-		struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu);
-		struct io_pgtable_domain_attr pgtbl_cfg;
-
-		/*
-		 * This allows GPU to set the bus attributes required to use system
-		 * cache on behalf of the iommu page table walker.
-		 */
-		if (!IS_ERR_OR_NULL(a6xx_gpu->htw_llc_slice)) {
-			pgtbl_cfg.quirks = IO_PGTABLE_QUIRK_ARM_OUTER_WBWA;
-			iommu_domain_set_attr(iommu, DOMAIN_ATTR_IO_PGTABLE_CFG, &pgtbl_cfg);
-		}
-	}
-
 	mmu = msm_iommu_new(&pdev->dev, iommu);
 	if (IS_ERR(mmu)) {
 		iommu_domain_free(iommu);

drivers/gpu/drm/msm/adreno/adreno_gpu.h

@@ -212,11 +212,6 @@ static inline int adreno_is_a540(struct adreno_gpu *gpu)
 	return gpu->revn == 540;
 }
 
-static inline bool adreno_is_a6xx(struct adreno_gpu *gpu)
-{
-	return ((gpu->revn < 700 && gpu->revn > 599));
-}
-
 static inline int adreno_is_a618(struct adreno_gpu *gpu)
 {
        return gpu->revn == 618;
@@ -278,6 +273,8 @@ struct msm_gem_address_space *
 adreno_iommu_create_address_space(struct msm_gpu *gpu,
 		struct platform_device *pdev);
 
+void adreno_set_llc_attributes(struct iommu_domain *iommu);
+
 /*
  * For a5xx and a6xx targets load the zap shader that is used to pull the GPU
  * out of secure mode