// SPDX-License-Identifier: GPL-2.0-or-later /* * drm gem framebuffer helper functions * * Copyright (C) 2017 Noralf Trønnes */ #include #include #include #include #include #include #include #include #include #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);