diff options
| -rw-r--r-- | drivers/gpu/drm/tegra/gem.c | 36 |
1 files changed, 32 insertions, 4 deletions
diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c index da32086cbeaf..c888bed4036f 100644 --- a/drivers/gpu/drm/tegra/gem.c +++ b/drivers/gpu/drm/tegra/gem.c @@ -219,19 +219,47 @@ static void tegra_bo_free(struct drm_device *drm, struct tegra_bo *bo) static int tegra_bo_get_pages(struct drm_device *drm, struct tegra_bo *bo, size_t size) { + struct scatterlist *s; + struct sg_table *sgt; + unsigned int i; + bo->pages = drm_gem_get_pages(&bo->gem); if (IS_ERR(bo->pages)) return PTR_ERR(bo->pages); bo->num_pages = size >> PAGE_SHIFT; - bo->sgt = drm_prime_pages_to_sg(bo->pages, bo->num_pages); - if (IS_ERR(bo->sgt)) { - drm_gem_put_pages(&bo->gem, bo->pages, false, false); - return PTR_ERR(bo->sgt); + sgt = drm_prime_pages_to_sg(bo->pages, bo->num_pages); + if (IS_ERR(sgt)) + goto put_pages; + + /* + * Fake up the SG table so that dma_map_sg() can be used to flush the + * pages associated with it. Note that this relies on the fact that + * the DMA API doesn't hook into IOMMU on Tegra, therefore mapping is + * only cache maintenance. + * + * TODO: Replace this by drm_clflash_sg() once it can be implemented + * without relying on symbols that are not exported. + */ + for_each_sg(sgt->sgl, s, sgt->nents, i) + sg_dma_address(s) = sg_phys(s); + + if (dma_map_sg(drm->dev, sgt->sgl, sgt->nents, DMA_TO_DEVICE) == 0) { + sgt = ERR_PTR(-ENOMEM); + goto release_sgt; } + bo->sgt = sgt; + return 0; + +release_sgt: + sg_free_table(sgt); + kfree(sgt); +put_pages: + drm_gem_put_pages(&bo->gem, bo->pages, false, false); + return PTR_ERR(sgt); } static int tegra_bo_alloc(struct drm_device *drm, struct tegra_bo *bo, |