1 files changed, 196 insertions, 28 deletions

diff --git a/drivers/gpu/drm/drm_gem_framebuffer_helper.c b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
index 3a7ace19a902..ccc2c71fa491 100644
--- a/drivers/gpu/drm/drm_gem_framebuffer_helper.c
+++ b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
@@ -21,6 +21,13 @@
 #include <drm/drm_modeset_helper.h>
 #include <drm/drm_simple_kms_helper.h>
 
+#define AFBC_HEADER_SIZE		16
+#define AFBC_TH_LAYOUT_ALIGNMENT	8
+#define AFBC_HDR_ALIGN			64
+#define AFBC_SUPERBLOCK_PIXELS		256
+#define AFBC_SUPERBLOCK_ALIGNMENT	128
+#define AFBC_TH_BODY_START_ALIGNMENT	4096
+
 /**
  * DOC: overview
  *
@@ -54,32 +61,25 @@ struct drm_gem_object *drm_gem_fb_get_obj(struct drm_framebuffer *fb,
 }
 EXPORT_SYMBOL_GPL(drm_gem_fb_get_obj);
 
-static struct drm_framebuffer *
-drm_gem_fb_alloc(struct drm_device *dev,
+static int
+drm_gem_fb_init(struct drm_device *dev,
+		 struct drm_framebuffer *fb,
 		 const struct drm_mode_fb_cmd2 *mode_cmd,
 		 struct drm_gem_object **obj, unsigned int num_planes,
 		 const struct drm_framebuffer_funcs *funcs)
 {
-	struct drm_framebuffer *fb;
 	int ret, i;
 
-	fb = kzalloc(sizeof(*fb), GFP_KERNEL);
-	if (!fb)
-		return ERR_PTR(-ENOMEM);
-
 	drm_helper_mode_fill_fb_struct(dev, fb, mode_cmd);
 
 	for (i = 0; i < num_planes; i++)
 		fb->obj[i] = obj[i];
 
 	ret = drm_framebuffer_init(dev, fb, funcs);
-	if (ret) {
+	if (ret)
 		drm_err(dev, "Failed to init framebuffer: %d\n", ret);
-		kfree(fb);
-		return ERR_PTR(ret);
-	}
 
-	return fb;
+	return ret;
 }
 
 /**
@@ -123,10 +123,13 @@ int drm_gem_fb_create_handle(struct drm_framebuffer *fb, struct drm_file *file,
 EXPORT_SYMBOL(drm_gem_fb_create_handle);
 
 /**
- * drm_gem_fb_create_with_funcs() - Helper function for the
- *                                  &drm_mode_config_funcs.fb_create
- *                                  callback
+ * drm_gem_fb_init_with_funcs() - Helper function for implementing
+ *				  &drm_mode_config_funcs.fb_create
+ *				  callback in cases when the driver
+ *				  allocates a subclass of
+ *				  struct drm_framebuffer
  * @dev: DRM device
+ * @fb: framebuffer object
  * @file: DRM file that holds the GEM handle(s) backing the framebuffer
  * @mode_cmd: Metadata from the userspace framebuffer creation request
  * @funcs: vtable to be used for the new framebuffer object
@@ -134,23 +137,26 @@ EXPORT_SYMBOL(drm_gem_fb_create_handle);
  * This function can be used to set &drm_framebuffer_funcs for drivers that need
  * custom framebuffer callbacks. Use drm_gem_fb_create() if you don't need to
  * change &drm_framebuffer_funcs. The function does buffer size validation.
+ * The buffer size validation is for a general case, though, so users should
+ * pay attention to the checks being appropriate for them or, at least,
+ * non-conflicting.
  *
  * Returns:
- * Pointer to a &drm_framebuffer on success or an error pointer on failure.
+ * Zero or a negative error code.
  */
-struct drm_framebuffer *
-drm_gem_fb_create_with_funcs(struct drm_device *dev, struct drm_file *file,
-			     const struct drm_mode_fb_cmd2 *mode_cmd,
-			     const struct drm_framebuffer_funcs *funcs)
+int drm_gem_fb_init_with_funcs(struct drm_device *dev,
+			       struct drm_framebuffer *fb,
+			       struct drm_file *file,
+			       const struct drm_mode_fb_cmd2 *mode_cmd,
+			       const struct drm_framebuffer_funcs *funcs)
 {
 	const struct drm_format_info *info;
 	struct drm_gem_object *objs[4];
-	struct drm_framebuffer *fb;
 	int ret, i;
 
 	info = drm_get_format_info(dev, mode_cmd);
 	if (!info)
-		return ERR_PTR(-EINVAL);
+		return -EINVAL;
 
 	for (i = 0; i < info->num_planes; i++) {
 		unsigned int width = mode_cmd->width / (i ? info->hsub : 1);
@@ -175,19 +181,55 @@ drm_gem_fb_create_with_funcs(struct drm_device *dev, struct drm_file *file,
 		}
 	}
 
-	fb = drm_gem_fb_alloc(dev, mode_cmd, objs, i, funcs);
-	if (IS_ERR(fb)) {
-		ret = PTR_ERR(fb);
+	ret = drm_gem_fb_init(dev, fb, mode_cmd, objs, i, funcs);
+	if (ret)
 		goto err_gem_object_put;
-	}
 
-	return fb;
+	return 0;
 
 err_gem_object_put:
 	for (i--; i >= 0; i--)
 		drm_gem_object_put_unlocked(objs[i]);
 
-	return ERR_PTR(ret);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(drm_gem_fb_init_with_funcs);
+
+/**
+ * drm_gem_fb_create_with_funcs() - Helper function for the
+ *                                  &drm_mode_config_funcs.fb_create
+ *                                  callback
+ * @dev: DRM device
+ * @file: DRM file that holds the GEM handle(s) backing the framebuffer
+ * @mode_cmd: Metadata from the userspace framebuffer creation request
+ * @funcs: vtable to be used for the new framebuffer object
+ *
+ * This function can be used to set &drm_framebuffer_funcs for drivers that need
+ * custom framebuffer callbacks. Use drm_gem_fb_create() if you don't need to
+ * change &drm_framebuffer_funcs. The function does buffer size validation.
+ *
+ * Returns:
+ * Pointer to a &drm_framebuffer on success or an error pointer on failure.
+ */
+struct drm_framebuffer *
+drm_gem_fb_create_with_funcs(struct drm_device *dev, struct drm_file *file,
+			     const struct drm_mode_fb_cmd2 *mode_cmd,
+			     const struct drm_framebuffer_funcs *funcs)
+{
+	struct drm_framebuffer *fb;
+	int ret;
+
+	fb = kzalloc(sizeof(*fb), GFP_KERNEL);
+	if (!fb)
+		return ERR_PTR(-ENOMEM);
+
+	ret = drm_gem_fb_init_with_funcs(dev, fb, file, mode_cmd, funcs);
+	if (ret) {
+		kfree(fb);
+		return ERR_PTR(ret);
+	}
+
+	return fb;
 }
 EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_funcs);
 
@@ -265,6 +307,132 @@ drm_gem_fb_create_with_dirty(struct drm_device *dev, struct drm_file *file,
 }
 EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_dirty);
 
+static __u32 drm_gem_afbc_get_bpp(struct drm_device *dev,
+				  const struct drm_mode_fb_cmd2 *mode_cmd)
+{
+	const struct drm_format_info *info;
+
+	info = drm_get_format_info(dev, mode_cmd);
+
+	/* use whatever a driver has set */
+	if (info->cpp[0])
+		return info->cpp[0] * 8;
+
+	/* guess otherwise */
+	switch (info->format) {
+	case DRM_FORMAT_YUV420_8BIT:
+		return 12;
+	case DRM_FORMAT_YUV420_10BIT:
+		return 15;
+	case DRM_FORMAT_VUY101010:
+		return 30;
+	default:
+		break;
+	}
+
+	/* all attempts failed */
+	return 0;
+}
+
+static int drm_gem_afbc_min_size(struct drm_device *dev,
+				 const struct drm_mode_fb_cmd2 *mode_cmd,
+				 struct drm_afbc_framebuffer *afbc_fb)
+{
+	__u32 n_blocks, w_alignment, h_alignment, hdr_alignment;
+	/* remove bpp when all users properly encode cpp in drm_format_info */
+	__u32 bpp;
+
+	switch (mode_cmd->modifier[0] & AFBC_FORMAT_MOD_BLOCK_SIZE_MASK) {
+	case AFBC_FORMAT_MOD_BLOCK_SIZE_16x16:
+		afbc_fb->block_width = 16;
+		afbc_fb->block_height = 16;
+		break;
+	case AFBC_FORMAT_MOD_BLOCK_SIZE_32x8:
+		afbc_fb->block_width = 32;
+		afbc_fb->block_height = 8;
+		break;
+	/* no user exists yet - fall through */
+	case AFBC_FORMAT_MOD_BLOCK_SIZE_64x4:
+	case AFBC_FORMAT_MOD_BLOCK_SIZE_32x8_64x4:
+	default:
+		drm_dbg_kms(dev, "Invalid AFBC_FORMAT_MOD_BLOCK_SIZE: %lld.\n",
+			    mode_cmd->modifier[0]
+			    & AFBC_FORMAT_MOD_BLOCK_SIZE_MASK);
+		return -EINVAL;
+	}
+
+	/* tiled header afbc */
+	w_alignment = afbc_fb->block_width;
+	h_alignment = afbc_fb->block_height;
+	hdr_alignment = AFBC_HDR_ALIGN;
+	if (mode_cmd->modifier[0] & AFBC_FORMAT_MOD_TILED) {
+		w_alignment *= AFBC_TH_LAYOUT_ALIGNMENT;
+		h_alignment *= AFBC_TH_LAYOUT_ALIGNMENT;
+		hdr_alignment = AFBC_TH_BODY_START_ALIGNMENT;
+	}
+
+	afbc_fb->aligned_width = ALIGN(mode_cmd->width, w_alignment);
+	afbc_fb->aligned_height = ALIGN(mode_cmd->height, h_alignment);
+	afbc_fb->offset = mode_cmd->offsets[0];
+
+	bpp = drm_gem_afbc_get_bpp(dev, mode_cmd);
+	if (!bpp) {
+		drm_dbg_kms(dev, "Invalid AFBC bpp value: %d\n", bpp);
+		return -EINVAL;
+	}
+
+	n_blocks = (afbc_fb->aligned_width * afbc_fb->aligned_height)
+		   / AFBC_SUPERBLOCK_PIXELS;
+	afbc_fb->afbc_size = ALIGN(n_blocks * AFBC_HEADER_SIZE, hdr_alignment);
+	afbc_fb->afbc_size += n_blocks * ALIGN(bpp * AFBC_SUPERBLOCK_PIXELS / 8,
+					       AFBC_SUPERBLOCK_ALIGNMENT);
+
+	return 0;
+}
+
+/**
+ * drm_gem_fb_afbc_init() - Helper function for drivers using afbc to
+ *			    fill and validate all the afbc-specific
+ *			    struct drm_afbc_framebuffer members
+ *
+ * @dev: DRM device
+ * @afbc_fb: afbc-specific framebuffer
+ * @mode_cmd: Metadata from the userspace framebuffer creation request
+ * @afbc_fb: afbc framebuffer
+ *
+ * This function can be used by drivers which support afbc to complete
+ * the preparation of struct drm_afbc_framebuffer. It must be called after
+ * allocating the said struct and calling drm_gem_fb_init_with_funcs().
+ * It is caller's responsibility to put afbc_fb->base.obj objects in case
+ * the call is unsuccessful.
+ *
+ * Returns:
+ * Zero on success or a negative error value on failure.
+ */
+int drm_gem_fb_afbc_init(struct drm_device *dev,
+			 const struct drm_mode_fb_cmd2 *mode_cmd,
+			 struct drm_afbc_framebuffer *afbc_fb)
+{
+	const struct drm_format_info *info;
+	struct drm_gem_object **objs;
+	int ret;
+
+	objs = afbc_fb->base.obj;
+	info = drm_get_format_info(dev, mode_cmd);
+	if (!info)
+		return -EINVAL;
+
+	ret = drm_gem_afbc_min_size(dev, mode_cmd, afbc_fb);
+	if (ret < 0)
+		return ret;
+
+	if (objs[0]->size < afbc_fb->afbc_size)
+		return -EINVAL;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(drm_gem_fb_afbc_init);
+
 /**
  * drm_gem_fb_prepare_fb() - Prepare a GEM backed framebuffer
  * @plane: Plane