// 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_drv.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;
}
if (drm_drv_uses_atomic_modeset(dev) &&
!drm_any_plane_has_format(dev, mode_cmd->pixel_format,
mode_cmd->modifier[0])) {
drm_dbg_kms(dev, "Unsupported pixel format %p4cc / modifier 0x%llx\n",
&mode_cmd->pixel_format, mode_cmd->modifier[0]);
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_unlocked(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_unlocked(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_unlocked(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);
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