Support importing certain dma_bufs back into gem - notably those which are either contiguous or are our own exports which do not use dma_map_sg().
Signed-off-by: Russell King rmk+kernel@arm.linux.org.uk --- drivers/gpu/drm/armada/armada_drv.c | 4 +- drivers/gpu/drm/armada/armada_fb.c | 6 +++ drivers/gpu/drm/armada/armada_gem.c | 81 ++++++++++++++++++++++++++++++++++- drivers/gpu/drm/armada/armada_gem.h | 4 ++ 4 files changed, 92 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/armada/armada_drv.c b/drivers/gpu/drm/armada/armada_drv.c index e0a08e9..268ea28 100644 --- a/drivers/gpu/drm/armada/armada_drv.c +++ b/drivers/gpu/drm/armada/armada_drv.c @@ -311,9 +311,9 @@ static struct drm_driver armada_drm_driver = { .gem_init_object = NULL, .gem_free_object = armada_gem_free_object, .prime_handle_to_fd = drm_gem_prime_handle_to_fd, - .prime_fd_to_handle = NULL, + .prime_fd_to_handle = drm_gem_prime_fd_to_handle, .gem_prime_export = armada_gem_prime_export, - .gem_prime_import = NULL, + .gem_prime_import = armada_gem_prime_import, .dumb_create = armada_gem_dumb_create, .dumb_map_offset = armada_gem_dumb_map_offset, .dumb_destroy = armada_gem_dumb_destroy, diff --git a/drivers/gpu/drm/armada/armada_fb.c b/drivers/gpu/drm/armada/armada_fb.c index 5154f04..28965e3 100644 --- a/drivers/gpu/drm/armada/armada_fb.c +++ b/drivers/gpu/drm/armada/armada_fb.c @@ -120,6 +120,12 @@ static struct drm_framebuffer *armada_fb_create(struct drm_device *dev, return ERR_PTR(-ENOENT); }
+ if (obj->obj.import_attach && !obj->sgt) { + ret = armada_gem_map_import(obj); + if (ret) + goto unref; + } + /* Framebuffer objects must have a valid device address for scanout */ if (obj->dev_addr == DMA_ERROR_CODE) { ret = -EINVAL; diff --git a/drivers/gpu/drm/armada/armada_gem.c b/drivers/gpu/drm/armada/armada_gem.c index d09fa14..ad517ce 100644 --- a/drivers/gpu/drm/armada/armada_gem.c +++ b/drivers/gpu/drm/armada/armada_gem.c @@ -70,6 +70,12 @@ void armada_gem_free_object(struct drm_gem_object *obj) iounmap(dobj->addr); }
+ if (dobj->obj.import_attach) { + /* We only ever display imported data */ + dma_buf_unmap_attachment(dobj->obj.import_attach, dobj->sgt, + DMA_TO_DEVICE); + drm_prime_gem_destroy(&dobj->obj, NULL); + }
drm_gem_object_release(&dobj->obj);
@@ -270,6 +276,12 @@ int armada_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev, goto err_unlock; }
+ /* Don't allow imported objects to be mapped */ + if (obj->obj.import_attach) { + ret = -EINVAL; + goto err_unlock; + } + if (!obj->obj.map_list.map) ret = drm_gem_create_mmap_offset(&obj->obj);
@@ -537,5 +549,72 @@ armada_gem_prime_export(struct drm_device *dev, struct drm_gem_object *obj, int flags) { return dma_buf_export(obj, &armada_gem_prime_dmabuf_ops, obj->size, - flags); + O_RDWR); +} + +struct drm_gem_object * +armada_gem_prime_import(struct drm_device *dev, struct dma_buf *buf) +{ + struct dma_buf_attachment *attach; + struct armada_gem_object *dobj; + + if (buf->ops == &armada_gem_prime_dmabuf_ops) { + struct drm_gem_object *obj = buf->priv; + if (obj->dev == dev) { + /* + * Importing our own dmabuf(s) increases the + * refcount on the gem object itself. + */ + drm_gem_object_reference(obj); + dma_buf_put(buf); + return obj; + } + } + + attach = dma_buf_attach(buf, dev->dev); + if (IS_ERR(attach)) + return ERR_CAST(attach); + + dobj = armada_gem_alloc_private_object(dev, buf->size); + if (!dobj) { + dma_buf_detach(buf, attach); + return ERR_PTR(-ENOMEM); + } + + dobj->obj.import_attach = attach; + + /* + * Don't call dma_buf_map_attachment() here - it maps the + * scatterlist immediately for DMA, and this is not always + * an appropriate thing to do. + */ + return &dobj->obj; +} + +int armada_gem_map_import(struct armada_gem_object *dobj) +{ + int ret; + + dobj->sgt = dma_buf_map_attachment(dobj->obj.import_attach, + DMA_TO_DEVICE); + if (!dobj->sgt) { + DRM_ERROR("dma_buf_map_attachment() returned NULL\n"); + return -EINVAL; + } + if (IS_ERR(dobj->sgt)) { + ret = PTR_ERR(dobj->sgt); + dobj->sgt = NULL; + DRM_ERROR("dma_buf_map_attachment() error: %d\n", ret); + return ret; + } + if (dobj->sgt->nents > 1) { + DRM_ERROR("dma_buf_map_attachment() returned an (unsupported) scattered list\n"); + return -EINVAL; + } + if (sg_dma_len(dobj->sgt->sgl) < dobj->obj.size) { + DRM_ERROR("dma_buf_map_attachment() returned a small buffer\n"); + return -EINVAL; + } + dobj->dev_addr = sg_dma_address(dobj->sgt->sgl); + return 0; } diff --git a/drivers/gpu/drm/armada/armada_gem.h b/drivers/gpu/drm/armada/armada_gem.h index e3bce9f..00b6cd4 100644 --- a/drivers/gpu/drm/armada/armada_gem.h +++ b/drivers/gpu/drm/armada/armada_gem.h @@ -16,6 +16,7 @@ struct armada_gem_object { resource_size_t dev_addr; struct drm_mm_node *linear; /* for linear backed */ struct page *page; /* for page backed */ + struct sg_table *sgt; /* for imported */ void (*update)(void *); void *update_data; }; @@ -37,6 +38,9 @@ int armada_gem_dumb_destroy(struct drm_file *, struct drm_device *, uint32_t); struct dma_buf *armada_gem_prime_export(struct drm_device *dev, struct drm_gem_object *obj, int flags); +struct drm_gem_object *armada_gem_prime_import(struct drm_device *, + struct dma_buf *); +int armada_gem_map_import(struct armada_gem_object *);
static inline struct armada_gem_object *armada_gem_object_lookup( struct drm_device *dev, struct drm_file *dfile, unsigned handle)