Re: [PATCH v3 4/8] drm/panfrost: Split panfrost_mmu_map SG list mapping to its own function

On 02/08/2019 20:51, Rob Herring wrote:

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 Cc: Steven Price steven.price@arm.com Acked-by: Alyssa Rosenzweig alyssa.rosenzweig@collabora.com Signed-off-by: Rob Herring robh@kernel.org

Reviewed-by: Steven Price steven.price@arm.com

(Although I don't see a change from the previous posting which already had my R-b).

---

drivers/gpu/drm/panfrost/panfrost_mmu.c | 52 +++++++++++++++---------- 1 file changed, 31 insertions(+), 21 deletions(-)

diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index 92ac995dd9c6..b4ac149b2399 100644 --- 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;