drm/panfrost: Split panfrost_mmu_map SG list mapping to its own function

In preparation to create partial GPU mappings of BOs on page faults,
split out the SG list handling of panfrost_mmu_map().

Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Cc: Boris Brezillon <boris.brezillon@collabora.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Reviewed: Steven Price <steven.price@arm.com>
Acked-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190808222200.13176-5-robh@kernel.org

diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c
index 92ac995dd9c66be77484f5f634d463098607f91a..b4ac149b2399cb10c24bed20df03c039f1b82db3 100644 (file)
--- a/drivers/gpu/drm/panfrost/panfrost_mmu.c
+++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c
@@ -145,27 +145,13 @@ static size_t get_pgsize(u64 addr, size_t size)
        return SZ_2M;
 }
 
-int panfrost_mmu_map(struct panfrost_gem_object *bo)
+static int mmu_map_sg(struct panfrost_device *pfdev, u64 iova,
+                     int prot, struct sg_table *sgt)
 {
-       struct drm_gem_object *obj = &bo->base.base;
-       struct panfrost_device *pfdev = to_panfrost_device(obj->dev);
-       struct io_pgtable_ops *ops = pfdev->mmu->pgtbl_ops;
-       u64 iova = bo->node.start << PAGE_SHIFT;
        unsigned int count;
        struct scatterlist *sgl;
-       struct sg_table *sgt;
-       int ret;
-
-       if (WARN_ON(bo->is_mapped))
-               return 0;
-
-       sgt = drm_gem_shmem_get_pages_sgt(obj);
-       if (WARN_ON(IS_ERR(sgt)))
-               return PTR_ERR(sgt);
-
-       ret = pm_runtime_get_sync(pfdev->dev);
-       if (ret < 0)
-               return ret;
+       struct io_pgtable_ops *ops = pfdev->mmu->pgtbl_ops;
+       u64 start_iova = iova;
 
        mutex_lock(&pfdev->mmu->lock);
 
@@ -178,18 +164,42 @@ int panfrost_mmu_map(struct panfrost_gem_object *bo)
                while (len) {
                        size_t pgsize = get_pgsize(iova | paddr, len);
 
-                       ops->map(ops, iova, paddr, pgsize, IOMMU_WRITE | IOMMU_READ);
+                       ops->map(ops, iova, paddr, pgsize, prot);
                        iova += pgsize;
                        paddr += pgsize;
                        len -= pgsize;
                }
        }
 
-       mmu_hw_do_operation(pfdev, 0, bo->node.start << PAGE_SHIFT,
-                           bo->node.size << PAGE_SHIFT, AS_COMMAND_FLUSH_PT);
+       mmu_hw_do_operation(pfdev, 0, start_iova, iova - start_iova,
+                           AS_COMMAND_FLUSH_PT);
 
        mutex_unlock(&pfdev->mmu->lock);
 
+       return 0;
+}
+
+int panfrost_mmu_map(struct panfrost_gem_object *bo)
+{
+       struct drm_gem_object *obj = &bo->base.base;
+       struct panfrost_device *pfdev = to_panfrost_device(obj->dev);
+       struct sg_table *sgt;
+       int ret;
+       int prot = IOMMU_READ | IOMMU_WRITE;
+
+       if (WARN_ON(bo->is_mapped))
+               return 0;
+
+       sgt = drm_gem_shmem_get_pages_sgt(obj);
+       if (WARN_ON(IS_ERR(sgt)))
+               return PTR_ERR(sgt);
+
+       ret = pm_runtime_get_sync(pfdev->dev);
+       if (ret < 0)
+               return ret;
+
+       mmu_map_sg(pfdev, bo->node.start << PAGE_SHIFT, prot, sgt);
+
        pm_runtime_mark_last_busy(pfdev->dev);
        pm_runtime_put_autosuspend(pfdev->dev);
        bo->is_mapped = true;