drm/omap: gem: Refactor GEM object allocation

Split the individual steps of GEM object allocation and initialization
clearly. This improves readability and prepares for dma_buf import
support.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

diff --git a/drivers/gpu/drm/omapdrm/omap_gem.c b/drivers/gpu/drm/omapdrm/omap_gem.c
index c457520..36302e7 100644 (file)
--- a/drivers/gpu/drm/omapdrm/omap_gem.c
+++ b/drivers/gpu/drm/omapdrm/omap_gem.c
@@ -1374,67 +1374,80 @@ struct drm_gem_object *omap_gem_new(struct drm_device *dev,
        size_t size;
        int ret;
 
+       /* Validate the flags and compute the memory and cache flags. */
        if (flags & OMAP_BO_TILED) {
                if (!priv->usergart) {
                        dev_err(dev->dev, "Tiled buffers require DMM\n");
                        return NULL;
                }
 
-               /* tiled buffers are always shmem paged backed.. when they are
-                * scanned out, they are remapped into DMM/TILER
+               /*
+                * Tiled buffers are always shmem paged backed. When they are
+                * scanned out, they are remapped into DMM/TILER.
                 */
                flags &= ~OMAP_BO_SCANOUT;
+               flags |= OMAP_BO_MEM_SHMEM;
 
-               /* currently don't allow cached buffers.. there is some caching
-                * stuff that needs to be handled better
+               /*
+                * Currently don't allow cached buffers. There is some caching
+                * stuff that needs to be handled better.
                 */
                flags &= ~(OMAP_BO_CACHED|OMAP_BO_WC|OMAP_BO_UNCACHED);
                flags |= tiler_get_cpu_cache_flags();
-
-               /* align dimensions to slot boundaries... */
-               tiler_align(gem2fmt(flags),
-                               &gsize.tiled.width, &gsize.tiled.height);
-
-               /* ...and calculate size based on aligned dimensions */
-               size = tiler_size(gem2fmt(flags),
-                               gsize.tiled.width, gsize.tiled.height);
-       } else {
-               size = PAGE_ALIGN(gsize.bytes);
+       } else if ((flags & OMAP_BO_SCANOUT) && !priv->has_dmm) {
+               /*
+                * Use contiguous memory if we don't have DMM to remap
+                * discontiguous buffers.
+                */
+               flags |= OMAP_BO_MEM_DMA_API;
+       } else if (!(flags & OMAP_BO_MEM_EXT)) {
+               /*
+                * All other buffers not backed with external memory are
+                * shmem-backed.
+                */
+               flags |= OMAP_BO_MEM_SHMEM;
        }
 
+       /* Allocate the initialize the OMAP GEM object. */
        omap_obj = kzalloc(sizeof(*omap_obj), GFP_KERNEL);
        if (!omap_obj)
                return NULL;
 
        obj = &omap_obj->base;
+       omap_obj->flags = flags;
 
-       if ((flags & OMAP_BO_SCANOUT) && !priv->has_dmm) {
-               /* attempt to allocate contiguous memory if we don't
-                * have DMM for remappign discontiguous buffers
+       if (flags & OMAP_BO_TILED) {
+               /*
+                * For tiled buffers align dimensions to slot boundaries and
+                * calculate size based on aligned dimensions.
                 */
-               omap_obj->vaddr =  dma_alloc_writecombine(dev->dev, size,
-                               &omap_obj->paddr, GFP_KERNEL);
-               if (!omap_obj->vaddr) {
-                       kfree(omap_obj);
+               tiler_align(gem2fmt(flags), &gsize.tiled.width,
+                           &gsize.tiled.height);
 
-                       return NULL;
-               }
+               size = tiler_size(gem2fmt(flags), gsize.tiled.width,
+                                 gsize.tiled.height);
 
-               flags |= OMAP_BO_MEM_DMA_API;
+               omap_obj->width = gsize.tiled.width;
+               omap_obj->height = gsize.tiled.height;
+       } else {
+               size = PAGE_ALIGN(gsize.bytes);
        }
 
        spin_lock(&priv->list_lock);
        list_add(&omap_obj->mm_list, &priv->obj_list);
        spin_unlock(&priv->list_lock);
 
-       omap_obj->flags = flags;
-
-       if (flags & OMAP_BO_TILED) {
-               omap_obj->width = gsize.tiled.width;
-               omap_obj->height = gsize.tiled.height;
+       /* Allocate memory if needed. */
+       if (flags & OMAP_BO_MEM_DMA_API) {
+               omap_obj->vaddr = dma_alloc_writecombine(dev->dev, size,
+                                                        &omap_obj->paddr,
+                                                        GFP_KERNEL);
+               if (!omap_obj->vaddr)
+                       goto fail;
        }
 
-       if (flags & (OMAP_BO_MEM_DMA_API | OMAP_BO_MEM_EXT)) {
+       /* Initialize the GEM object. */
+       if (!(flags & OMAP_BO_MEM_SHMEM)) {
                drm_gem_private_object_init(dev, obj, size);
        } else {
                ret = drm_gem_object_init(dev, obj, size);
@@ -1443,8 +1456,6 @@ struct drm_gem_object *omap_gem_new(struct drm_device *dev,
 
                mapping = file_inode(obj->filp)->i_mapping;
                mapping_set_gfp_mask(mapping, GFP_USER | __GFP_DMA32);
-
-               omap_obj->flags |= OMAP_BO_MEM_SHMEM;
        }
 
        return obj;