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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/gpu/drm/drm_gem_framebuffer_helper.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpu/drm/drm_gem_framebuffer_helper.c')
-rw-r--r--drivers/gpu/drm/drm_gem_framebuffer_helper.c611
1 files changed, 611 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_gem_framebuffer_helper.c b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
new file mode 100644
index 000000000..880a49755
--- /dev/null
+++ b/drivers/gpu/drm/drm_gem_framebuffer_helper.c
@@ -0,0 +1,611 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * drm gem framebuffer helper functions
+ *
+ * Copyright (C) 2017 Noralf Trønnes
+ */
+
+#include <linux/slab.h>
+#include <linux/module.h>
+
+#include <drm/drm_damage_helper.h>
+#include <drm/drm_fb_helper.h>
+#include <drm/drm_fourcc.h>
+#include <drm/drm_framebuffer.h>
+#include <drm/drm_gem.h>
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_modeset_helper.h>
+
+#include "drm_internal.h"
+
+MODULE_IMPORT_NS(DMA_BUF);
+
+#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
+ *
+ * This library provides helpers for drivers that don't subclass
+ * &drm_framebuffer and use &drm_gem_object for their backing storage.
+ *
+ * Drivers without additional needs to validate framebuffers can simply use
+ * drm_gem_fb_create() and everything is wired up automatically. Other drivers
+ * can use all parts independently.
+ */
+
+/**
+ * drm_gem_fb_get_obj() - Get GEM object backing the framebuffer
+ * @fb: Framebuffer
+ * @plane: Plane index
+ *
+ * No additional reference is taken beyond the one that the &drm_frambuffer
+ * already holds.
+ *
+ * Returns:
+ * Pointer to &drm_gem_object for the given framebuffer and plane index or NULL
+ * if it does not exist.
+ */
+struct drm_gem_object *drm_gem_fb_get_obj(struct drm_framebuffer *fb,
+ unsigned int plane)
+{
+ struct drm_device *dev = fb->dev;
+
+ if (drm_WARN_ON_ONCE(dev, plane >= ARRAY_SIZE(fb->obj)))
+ return NULL;
+ else if (drm_WARN_ON_ONCE(dev, !fb->obj[plane]))
+ return NULL;
+
+ return fb->obj[plane];
+}
+EXPORT_SYMBOL_GPL(drm_gem_fb_get_obj);
+
+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)
+{
+ unsigned int i;
+ int ret;
+
+ 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)
+ drm_err(dev, "Failed to init framebuffer: %d\n", ret);
+
+ return ret;
+}
+
+/**
+ * drm_gem_fb_destroy - Free GEM backed framebuffer
+ * @fb: Framebuffer
+ *
+ * Frees a GEM backed framebuffer with its backing buffer(s) and the structure
+ * itself. Drivers can use this as their &drm_framebuffer_funcs->destroy
+ * callback.
+ */
+void drm_gem_fb_destroy(struct drm_framebuffer *fb)
+{
+ unsigned int i;
+
+ for (i = 0; i < fb->format->num_planes; i++)
+ drm_gem_object_put(fb->obj[i]);
+
+ drm_framebuffer_cleanup(fb);
+ kfree(fb);
+}
+EXPORT_SYMBOL(drm_gem_fb_destroy);
+
+/**
+ * drm_gem_fb_create_handle - Create handle for GEM backed framebuffer
+ * @fb: Framebuffer
+ * @file: DRM file to register the handle for
+ * @handle: Pointer to return the created handle
+ *
+ * This function creates a handle for the GEM object backing the framebuffer.
+ * Drivers can use this as their &drm_framebuffer_funcs->create_handle
+ * callback. The GETFB IOCTL calls into this callback.
+ *
+ * Returns:
+ * 0 on success or a negative error code on failure.
+ */
+int drm_gem_fb_create_handle(struct drm_framebuffer *fb, struct drm_file *file,
+ unsigned int *handle)
+{
+ return drm_gem_handle_create(file, fb->obj[0], handle);
+}
+EXPORT_SYMBOL(drm_gem_fb_create_handle);
+
+/**
+ * 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
+ *
+ * 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:
+ * Zero or a negative error code.
+ */
+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[DRM_FORMAT_MAX_PLANES];
+ unsigned int i;
+ int ret;
+
+ info = drm_get_format_info(dev, mode_cmd);
+ if (!info) {
+ drm_dbg_kms(dev, "Failed to get FB format info\n");
+ return -EINVAL;
+ }
+
+ for (i = 0; i < info->num_planes; i++) {
+ unsigned int width = mode_cmd->width / (i ? info->hsub : 1);
+ unsigned int height = mode_cmd->height / (i ? info->vsub : 1);
+ unsigned int min_size;
+
+ objs[i] = drm_gem_object_lookup(file, mode_cmd->handles[i]);
+ if (!objs[i]) {
+ drm_dbg_kms(dev, "Failed to lookup GEM object\n");
+ ret = -ENOENT;
+ goto err_gem_object_put;
+ }
+
+ min_size = (height - 1) * mode_cmd->pitches[i]
+ + drm_format_info_min_pitch(info, i, width)
+ + mode_cmd->offsets[i];
+
+ if (objs[i]->size < min_size) {
+ drm_dbg_kms(dev,
+ "GEM object size (%zu) smaller than minimum size (%u) for plane %d\n",
+ objs[i]->size, min_size, i);
+ drm_gem_object_put(objs[i]);
+ ret = -EINVAL;
+ goto err_gem_object_put;
+ }
+ }
+
+ ret = drm_gem_fb_init(dev, fb, mode_cmd, objs, i, funcs);
+ if (ret)
+ goto err_gem_object_put;
+
+ return 0;
+
+err_gem_object_put:
+ while (i > 0) {
+ --i;
+ drm_gem_object_put(objs[i]);
+ }
+ 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);
+
+static const struct drm_framebuffer_funcs drm_gem_fb_funcs = {
+ .destroy = drm_gem_fb_destroy,
+ .create_handle = drm_gem_fb_create_handle,
+};
+
+/**
+ * drm_gem_fb_create() - 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
+ *
+ * This function creates a new framebuffer object described by
+ * &drm_mode_fb_cmd2. This description includes handles for the buffer(s)
+ * backing the framebuffer.
+ *
+ * If your hardware has special alignment or pitch requirements these should be
+ * checked before calling this function. The function does buffer size
+ * validation. Use drm_gem_fb_create_with_dirty() if you need framebuffer
+ * flushing.
+ *
+ * Drivers can use this as their &drm_mode_config_funcs.fb_create callback.
+ * The ADDFB2 IOCTL calls into this callback.
+ *
+ * Returns:
+ * Pointer to a &drm_framebuffer on success or an error pointer on failure.
+ */
+struct drm_framebuffer *
+drm_gem_fb_create(struct drm_device *dev, struct drm_file *file,
+ const struct drm_mode_fb_cmd2 *mode_cmd)
+{
+ return drm_gem_fb_create_with_funcs(dev, file, mode_cmd,
+ &drm_gem_fb_funcs);
+}
+EXPORT_SYMBOL_GPL(drm_gem_fb_create);
+
+static const struct drm_framebuffer_funcs drm_gem_fb_funcs_dirtyfb = {
+ .destroy = drm_gem_fb_destroy,
+ .create_handle = drm_gem_fb_create_handle,
+ .dirty = drm_atomic_helper_dirtyfb,
+};
+
+/**
+ * drm_gem_fb_create_with_dirty() - 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
+ *
+ * This function creates a new framebuffer object described by
+ * &drm_mode_fb_cmd2. This description includes handles for the buffer(s)
+ * backing the framebuffer. drm_atomic_helper_dirtyfb() is used for the dirty
+ * callback giving framebuffer flushing through the atomic machinery. Use
+ * drm_gem_fb_create() if you don't need the dirty callback.
+ * The function does buffer size validation.
+ *
+ * Drivers should also call drm_plane_enable_fb_damage_clips() on all planes
+ * to enable userspace to use damage clips also with the ATOMIC IOCTL.
+ *
+ * Drivers can use this as their &drm_mode_config_funcs.fb_create callback.
+ * The ADDFB2 IOCTL calls into this callback.
+ *
+ * Returns:
+ * Pointer to a &drm_framebuffer on success or an error pointer on failure.
+ */
+struct drm_framebuffer *
+drm_gem_fb_create_with_dirty(struct drm_device *dev, struct drm_file *file,
+ const struct drm_mode_fb_cmd2 *mode_cmd)
+{
+ return drm_gem_fb_create_with_funcs(dev, file, mode_cmd,
+ &drm_gem_fb_funcs_dirtyfb);
+}
+EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_dirty);
+
+/**
+ * drm_gem_fb_vmap - maps all framebuffer BOs into kernel address space
+ * @fb: the framebuffer
+ * @map: returns the mapping's address for each BO
+ * @data: returns the data address for each BO, can be NULL
+ *
+ * This function maps all buffer objects of the given framebuffer into
+ * kernel address space and stores them in struct iosys_map. If the
+ * mapping operation fails for one of the BOs, the function unmaps the
+ * already established mappings automatically.
+ *
+ * Callers that want to access a BO's stored data should pass @data.
+ * The argument returns the addresses of the data stored in each BO. This
+ * is different from @map if the framebuffer's offsets field is non-zero.
+ *
+ * Both, @map and @data, must each refer to arrays with at least
+ * fb->format->num_planes elements.
+ *
+ * See drm_gem_fb_vunmap() for unmapping.
+ *
+ * Returns:
+ * 0 on success, or a negative errno code otherwise.
+ */
+int drm_gem_fb_vmap(struct drm_framebuffer *fb, struct iosys_map *map,
+ struct iosys_map *data)
+{
+ struct drm_gem_object *obj;
+ unsigned int i;
+ int ret;
+
+ for (i = 0; i < fb->format->num_planes; ++i) {
+ obj = drm_gem_fb_get_obj(fb, i);
+ if (!obj) {
+ ret = -EINVAL;
+ goto err_drm_gem_vunmap;
+ }
+ ret = drm_gem_vmap(obj, &map[i]);
+ if (ret)
+ goto err_drm_gem_vunmap;
+ }
+
+ if (data) {
+ for (i = 0; i < fb->format->num_planes; ++i) {
+ memcpy(&data[i], &map[i], sizeof(data[i]));
+ if (iosys_map_is_null(&data[i]))
+ continue;
+ iosys_map_incr(&data[i], fb->offsets[i]);
+ }
+ }
+
+ return 0;
+
+err_drm_gem_vunmap:
+ while (i) {
+ --i;
+ obj = drm_gem_fb_get_obj(fb, i);
+ if (!obj)
+ continue;
+ drm_gem_vunmap(obj, &map[i]);
+ }
+ return ret;
+}
+EXPORT_SYMBOL(drm_gem_fb_vmap);
+
+/**
+ * drm_gem_fb_vunmap - unmaps framebuffer BOs from kernel address space
+ * @fb: the framebuffer
+ * @map: mapping addresses as returned by drm_gem_fb_vmap()
+ *
+ * This function unmaps all buffer objects of the given framebuffer.
+ *
+ * See drm_gem_fb_vmap() for more information.
+ */
+void drm_gem_fb_vunmap(struct drm_framebuffer *fb, struct iosys_map *map)
+{
+ unsigned int i = fb->format->num_planes;
+ struct drm_gem_object *obj;
+
+ while (i) {
+ --i;
+ obj = drm_gem_fb_get_obj(fb, i);
+ if (!obj)
+ continue;
+ if (iosys_map_is_null(&map[i]))
+ continue;
+ drm_gem_vunmap(obj, &map[i]);
+ }
+}
+EXPORT_SYMBOL(drm_gem_fb_vunmap);
+
+static void __drm_gem_fb_end_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir,
+ unsigned int num_planes)
+{
+ struct dma_buf_attachment *import_attach;
+ struct drm_gem_object *obj;
+ int ret;
+
+ while (num_planes) {
+ --num_planes;
+ obj = drm_gem_fb_get_obj(fb, num_planes);
+ if (!obj)
+ continue;
+ import_attach = obj->import_attach;
+ if (!import_attach)
+ continue;
+ ret = dma_buf_end_cpu_access(import_attach->dmabuf, dir);
+ if (ret)
+ drm_err(fb->dev, "dma_buf_end_cpu_access(%u, %d) failed: %d\n",
+ ret, num_planes, dir);
+ }
+}
+
+/**
+ * drm_gem_fb_begin_cpu_access - prepares GEM buffer objects for CPU access
+ * @fb: the framebuffer
+ * @dir: access mode
+ *
+ * Prepares a framebuffer's GEM buffer objects for CPU access. This function
+ * must be called before accessing the BO data within the kernel. For imported
+ * BOs, the function calls dma_buf_begin_cpu_access().
+ *
+ * See drm_gem_fb_end_cpu_access() for signalling the end of CPU access.
+ *
+ * Returns:
+ * 0 on success, or a negative errno code otherwise.
+ */
+int drm_gem_fb_begin_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir)
+{
+ struct dma_buf_attachment *import_attach;
+ struct drm_gem_object *obj;
+ unsigned int i;
+ int ret;
+
+ for (i = 0; i < fb->format->num_planes; ++i) {
+ obj = drm_gem_fb_get_obj(fb, i);
+ if (!obj) {
+ ret = -EINVAL;
+ goto err___drm_gem_fb_end_cpu_access;
+ }
+ import_attach = obj->import_attach;
+ if (!import_attach)
+ continue;
+ ret = dma_buf_begin_cpu_access(import_attach->dmabuf, dir);
+ if (ret)
+ goto err___drm_gem_fb_end_cpu_access;
+ }
+
+ return 0;
+
+err___drm_gem_fb_end_cpu_access:
+ __drm_gem_fb_end_cpu_access(fb, dir, i);
+ return ret;
+}
+EXPORT_SYMBOL(drm_gem_fb_begin_cpu_access);
+
+/**
+ * drm_gem_fb_end_cpu_access - signals end of CPU access to GEM buffer objects
+ * @fb: the framebuffer
+ * @dir: access mode
+ *
+ * Signals the end of CPU access to the given framebuffer's GEM buffer objects. This
+ * function must be paired with a corresponding call to drm_gem_fb_begin_cpu_access().
+ * For imported BOs, the function calls dma_buf_end_cpu_access().
+ *
+ * See also drm_gem_fb_begin_cpu_access().
+ */
+void drm_gem_fb_end_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir)
+{
+ __drm_gem_fb_end_cpu_access(fb, dir, fb->format->num_planes);
+}
+EXPORT_SYMBOL(drm_gem_fb_end_cpu_access);
+
+// TODO Drop this function and replace by drm_format_info_bpp() once all
+// DRM_FORMAT_* provide proper block info in drivers/gpu/drm/drm_fourcc.c
+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);
+
+ switch (info->format) {
+ case DRM_FORMAT_YUV420_8BIT:
+ return 12;
+ case DRM_FORMAT_YUV420_10BIT:
+ return 15;
+ case DRM_FORMAT_VUY101010:
+ return 30;
+ default:
+ return drm_format_info_bpp(info, 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);