Commit 3800391d authored by Thierry Reding's avatar Thierry Reding
Browse files

drm/tegra: Add PRIME support 



Implement very basic PRIME support. This currently only works with
buffers that are contiguous in memory and will refuse to import any
physically non-contiguous buffers.

Signed-off-by: default avatarThierry Reding <treding@nvidia.com>
parent 72d30286

drivers/gpu/drm/tegra/drm.c

+7 −1
Original line number Diff line number Diff line
@@ -580,7 +580,7 @@ static void tegra_debugfs_cleanup(struct drm_minor *minor) 
#endif



static struct drm_driver tegra_drm_driver = {

	.driver_features = DRIVER_MODESET | DRIVER_GEM,

	.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_PRIME,

	.load = tegra_drm_load,

	.unload = tegra_drm_unload,

	.open = tegra_drm_open,
@@ -598,6 +598,12 @@ static struct drm_driver tegra_drm_driver = { 


	.gem_free_object = tegra_bo_free_object,

	.gem_vm_ops = &tegra_bo_vm_ops,



	.prime_handle_to_fd = drm_gem_prime_handle_to_fd,

	.prime_fd_to_handle = drm_gem_prime_fd_to_handle,

	.gem_prime_export = tegra_gem_prime_export,

	.gem_prime_import = tegra_gem_prime_import,



	.dumb_create = tegra_bo_dumb_create,

	.dumb_map_offset = tegra_bo_dumb_map_offset,

	.dumb_destroy = drm_gem_dumb_destroy,

drivers/gpu/drm/tegra/gem.c

+179 −1
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ 
 * GNU General Public License for more details.

 */



#include <linux/dma-buf.h>

#include <drm/tegra_drm.h>



#include "gem.h"
@@ -173,13 +174,87 @@ struct tegra_bo *tegra_bo_create_with_handle(struct drm_file *file, 
	return ERR_PTR(ret);

}



struct tegra_bo *tegra_bo_import(struct drm_device *drm, struct dma_buf *buf)

{

	struct dma_buf_attachment *attach;

	struct tegra_bo *bo;

	ssize_t size;

	int err;



	bo = kzalloc(sizeof(*bo), GFP_KERNEL);

	if (!bo)

		return ERR_PTR(-ENOMEM);



	host1x_bo_init(&bo->base, &tegra_bo_ops);

	size = round_up(buf->size, PAGE_SIZE);



	err = drm_gem_object_init(drm, &bo->gem, size);

	if (err < 0)

		goto free;



	err = drm_gem_create_mmap_offset(&bo->gem);

	if (err < 0)

		goto release;



	attach = dma_buf_attach(buf, drm->dev);

	if (IS_ERR(attach)) {

		err = PTR_ERR(attach);

		goto free_mmap;

	}



	get_dma_buf(buf);



	bo->sgt = dma_buf_map_attachment(attach, DMA_TO_DEVICE);

	if (!bo->sgt) {

		err = -ENOMEM;

		goto detach;

	}



	if (IS_ERR(bo->sgt)) {

		err = PTR_ERR(bo->sgt);

		goto detach;

	}



	if (bo->sgt->nents > 1) {

		err = -EINVAL;

		goto detach;

	}



	bo->paddr = sg_dma_address(bo->sgt->sgl);

	bo->gem.import_attach = attach;



	return bo;



detach:

	if (!IS_ERR_OR_NULL(bo->sgt))

		dma_buf_unmap_attachment(attach, bo->sgt, DMA_TO_DEVICE);



	dma_buf_detach(buf, attach);

	dma_buf_put(buf);

free_mmap:

	drm_gem_free_mmap_offset(&bo->gem);

release:

	drm_gem_object_release(&bo->gem);

free:

	kfree(bo);



	return ERR_PTR(err);

}



void tegra_bo_free_object(struct drm_gem_object *gem)

{

	struct tegra_bo *bo = to_tegra_bo(gem);



	if (gem->import_attach) {

		dma_buf_unmap_attachment(gem->import_attach, bo->sgt,

					 DMA_TO_DEVICE);

		drm_prime_gem_destroy(gem, NULL);

	} else {

		tegra_bo_destroy(gem->dev, bo);

	}



	drm_gem_free_mmap_offset(gem);

	drm_gem_object_release(gem);

	tegra_bo_destroy(gem->dev, bo);



	kfree(bo);

}
@@ -255,3 +330,106 @@ int tegra_drm_mmap(struct file *file, struct vm_area_struct *vma) 


	return ret;

}



static struct sg_table *

tegra_gem_prime_map_dma_buf(struct dma_buf_attachment *attach,

			    enum dma_data_direction dir)

{

	struct drm_gem_object *gem = attach->dmabuf->priv;

	struct tegra_bo *bo = to_tegra_bo(gem);

	struct sg_table *sgt;



	sgt = kmalloc(sizeof(*sgt), GFP_KERNEL);

	if (!sgt)

		return NULL;



	if (sg_alloc_table(sgt, 1, GFP_KERNEL)) {

		kfree(sgt);

		return NULL;

	}



	sg_dma_address(sgt->sgl) = bo->paddr;

	sg_dma_len(sgt->sgl) = gem->size;



	return sgt;

}



static void tegra_gem_prime_unmap_dma_buf(struct dma_buf_attachment *attach,

					  struct sg_table *sgt,

					  enum dma_data_direction dir)

{

	sg_free_table(sgt);

	kfree(sgt);

}



static void tegra_gem_prime_release(struct dma_buf *buf)

{

	drm_gem_dmabuf_release(buf);

}



static void *tegra_gem_prime_kmap_atomic(struct dma_buf *buf,

					 unsigned long page)

{

	return NULL;

}



static void tegra_gem_prime_kunmap_atomic(struct dma_buf *buf,

					  unsigned long page,

					  void *addr)

{

}



static void *tegra_gem_prime_kmap(struct dma_buf *buf, unsigned long page)

{

	return NULL;

}



static void tegra_gem_prime_kunmap(struct dma_buf *buf, unsigned long page,

				   void *addr)

{

}



static int tegra_gem_prime_mmap(struct dma_buf *buf, struct vm_area_struct *vma)

{

	return -EINVAL;

}



static const struct dma_buf_ops tegra_gem_prime_dmabuf_ops = {

	.map_dma_buf = tegra_gem_prime_map_dma_buf,

	.unmap_dma_buf = tegra_gem_prime_unmap_dma_buf,

	.release = tegra_gem_prime_release,

	.kmap_atomic = tegra_gem_prime_kmap_atomic,

	.kunmap_atomic = tegra_gem_prime_kunmap_atomic,

	.kmap = tegra_gem_prime_kmap,

	.kunmap = tegra_gem_prime_kunmap,

	.mmap = tegra_gem_prime_mmap,

};



struct dma_buf *tegra_gem_prime_export(struct drm_device *drm,

				       struct drm_gem_object *gem,

				       int flags)

{

	return dma_buf_export(gem, &tegra_gem_prime_dmabuf_ops, gem->size,

			      flags);

}



struct drm_gem_object *tegra_gem_prime_import(struct drm_device *drm,

					      struct dma_buf *buf)

{

	struct tegra_bo *bo;



	if (buf->ops == &tegra_gem_prime_dmabuf_ops) {

		struct drm_gem_object *gem = buf->priv;



		if (gem->dev == drm) {

			drm_gem_object_reference(gem);

			return gem;

		}

	}



	bo = tegra_bo_import(drm, buf);

	if (IS_ERR(bo))

		return ERR_CAST(bo);



	return &bo->gem;

}

drivers/gpu/drm/tegra/gem.h

+7 −0
Original line number Diff line number Diff line
@@ -31,6 +31,7 @@ struct tegra_bo { 
	struct drm_gem_object gem;

	struct host1x_bo base;

	unsigned long flags;

	struct sg_table *sgt;

	dma_addr_t paddr;

	void *vaddr;

};
@@ -57,4 +58,10 @@ int tegra_drm_mmap(struct file *file, struct vm_area_struct *vma); 


extern const struct vm_operations_struct tegra_bo_vm_ops;



struct dma_buf *tegra_gem_prime_export(struct drm_device *drm,

				       struct drm_gem_object *gem,

				       int flags);

struct drm_gem_object *tegra_gem_prime_import(struct drm_device *drm,

					      struct dma_buf *buf);



#endif