// SPDX-License-Identifier: GPL-2.0-or-later #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static const struct drm_gem_object_funcs drm_gem_vram_object_funcs; /** * DOC: overview * * This library provides &struct drm_gem_vram_object (GEM VRAM), a GEM * buffer object that is backed by video RAM (VRAM). It can be used for * framebuffer devices with dedicated memory. * * The data structure &struct drm_vram_mm and its helpers implement a memory * manager for simple framebuffer devices with dedicated video memory. GEM * VRAM buffer objects are either placed in the video memory or remain evicted * to system memory. * * With the GEM interface userspace applications create, manage and destroy * graphics buffers, such as an on-screen framebuffer. GEM does not provide * an implementation of these interfaces. It's up to the DRM driver to * provide an implementation that suits the hardware. If the hardware device * contains dedicated video memory, the DRM driver can use the VRAM helper * library. Each active buffer object is stored in video RAM. Active * buffer are used for drawing the current frame, typically something like * the frame's scanout buffer or the cursor image. If there's no more space * left in VRAM, inactive GEM objects can be moved to system memory. * * To initialize the VRAM helper library call drmm_vram_helper_alloc_mm(). * The function allocates and initializes an instance of &struct drm_vram_mm * in &struct drm_device.vram_mm . Use &DRM_GEM_VRAM_DRIVER to initialize * &struct drm_driver and &DRM_VRAM_MM_FILE_OPERATIONS to initialize * &struct file_operations; as illustrated below. * * .. code-block:: c * * struct file_operations fops ={ * .owner = THIS_MODULE, * DRM_VRAM_MM_FILE_OPERATION * }; * struct drm_driver drv = { * .driver_feature = DRM_ ... , * .fops = &fops, * DRM_GEM_VRAM_DRIVER * }; * * int init_drm_driver() * { * struct drm_device *dev; * uint64_t vram_base; * unsigned long vram_size; * int ret; * * // setup device, vram base and size * // ... * * ret = drmm_vram_helper_alloc_mm(dev, vram_base, vram_size); * if (ret) * return ret; * return 0; * } * * This creates an instance of &struct drm_vram_mm, exports DRM userspace * interfaces for GEM buffer management and initializes file operations to * allow for accessing created GEM buffers. With this setup, the DRM driver * manages an area of video RAM with VRAM MM and provides GEM VRAM objects * to userspace. * * You don't have to clean up the instance of VRAM MM. * drmm_vram_helper_alloc_mm() is a managed interface that installs a * clean-up handler to run during the DRM device's release. * * For drawing or scanout operations, rsp. buffer objects have to be pinned * in video RAM. Call drm_gem_vram_pin() with &DRM_GEM_VRAM_PL_FLAG_VRAM or * &DRM_GEM_VRAM_PL_FLAG_SYSTEM to pin a buffer object in video RAM or system * memory. Call drm_gem_vram_unpin() to release the pinned object afterwards. * * A buffer object that is pinned in video RAM has a fixed address within that * memory region. Call drm_gem_vram_offset() to retrieve this value. Typically * it's used to program the hardware's scanout engine for framebuffers, set * the cursor overlay's image for a mouse cursor, or use it as input to the * hardware's draing engine. * * To access a buffer object's memory from the DRM driver, call * drm_gem_vram_vmap(). It maps the buffer into kernel address * space and returns the memory address. Use drm_gem_vram_vunmap() to * release the mapping. */ /* * Buffer-objects helpers */ static void drm_gem_vram_cleanup(struct drm_gem_vram_object *gbo) { /* We got here via ttm_bo_put(), which means that the * TTM buffer object in 'bo' has already been cleaned * up; only release the GEM object. */ WARN_ON(gbo->vmap_use_count); WARN_ON(dma_buf_map_is_set(&gbo->map)); drm_gem_object_release(&gbo->bo.base); } static void drm_gem_vram_destroy(struct drm_gem_vram_object *gbo) { drm_gem_vram_cleanup(gbo); kfree(gbo); } static void ttm_buffer_object_destroy(struct ttm_buffer_object *bo) { struct drm_gem_vram_object *gbo = drm_gem_vram_of_bo(bo); drm_gem_vram_destroy(gbo); } static void drm_gem_vram_placement(struct drm_gem_vram_object *gbo, unsigned long pl_flag) { u32 invariant_flags = 0; unsigned int i; unsigned int c = 0; if (pl_flag & DRM_GEM_VRAM_PL_FLAG_TOPDOWN) invariant_flags = TTM_PL_FLAG_TOPDOWN; gbo->placement.placement = gbo->placements; gbo->placement.busy_placement = gbo->placements; if (pl_flag & DRM_GEM_VRAM_PL_FLAG_VRAM) { gbo->placements[c].mem_type = TTM_PL_VRAM; gbo->placements[c++].flags = invariant_flags; } if (pl_flag & DRM_GEM_VRAM_PL_FLAG_SYSTEM || !c) { gbo->placements[c].mem_type = TTM_PL_SYSTEM; gbo->placements[c++].flags = invariant_flags; } gbo->placement.num_placement = c; gbo->placement.num_busy_placement = c; for (i = 0; i < c; ++i) { gbo->placements[i].fpfn = 0; gbo->placements[i].lpfn = 0; } } /** * drm_gem_vram_create() - Creates a VRAM-backed GEM object * @dev: the DRM device * @size: the buffer size in bytes * @pg_align: the buffer's alignment in multiples of the page size * * GEM objects are allocated by calling struct drm_driver.gem_create_object, * if set. Otherwise kzalloc() will be used. Drivers can set their own GEM * object functions in struct drm_driver.gem_create_object. If no functions * are set, the new GEM object will use the default functions from GEM VRAM * helpers. * * Returns: * A new instance of &struct drm_gem_vram_object on success, or * an ERR_PTR()-encoded error code otherwise. */ struct drm_gem_vram_object *drm_gem_vram_create(struct drm_device *dev, size_t size, unsigned long pg_align) { struct drm_gem_vram_object *gbo; struct drm_gem_object *gem; struct drm_vram_mm *vmm = dev->vram_mm; struct ttm_device *bdev; int ret; if (WARN_ONCE(!vmm, "VRAM MM not initialized")) return ERR_PTR(-EINVAL); if (dev->driver->gem_create_object) { gem = dev->driver->gem_create_object(dev, size); if (!gem) return ERR_PTR(-ENOMEM); gbo = drm_gem_vram_of_gem(gem); } else { gbo = kzalloc(sizeof(*gbo), GFP_KERNEL); if (!gbo) return ERR_PTR(-ENOMEM); gem = &gbo->bo.base; } if (!gem->funcs) gem->funcs = &drm_gem_vram_object_funcs; ret = drm_gem_object_init(dev, gem, size); if (ret) { kfree(gbo); return ERR_PTR(ret); } bdev = &vmm->bdev; gbo->bo.bdev = bdev; drm_gem_vram_placement(gbo, DRM_GEM_VRAM_PL_FLAG_SYSTEM); /* * A failing ttm_bo_init will call ttm_buffer_object_destroy * to release gbo->bo.base and kfree gbo. */ ret = ttm_bo_init(bdev, &gbo->bo, size, ttm_bo_type_device, &gbo->placement, pg_align, false, NULL, NULL, ttm_buffer_object_destroy); if (ret) return ERR_PTR(ret); return gbo; } EXPORT_SYMBOL(drm_gem_vram_create); /** * drm_gem_vram_put() - Releases a reference to a VRAM-backed GEM object * @gbo: the GEM VRAM object * * See ttm_bo_put() for more information. */ void drm_gem_vram_put(struct drm_gem_vram_object *gbo) { ttm_bo_put(&gbo->bo); } EXPORT_SYMBOL(drm_gem_vram_put); static u64 drm_gem_vram_pg_offset(struct drm_gem_vram_object *gbo) { /* Keep TTM behavior for now, remove when drivers are audited */ if (WARN_ON_ONCE(!gbo->bo.resource->mm_node)) return 0; return gbo->bo.resource->start; } /** * drm_gem_vram_offset() - \ Returns a GEM VRAM object's offset in video memory * @gbo: the GEM VRAM object * * This function returns the buffer object's offset in the device's video * memory. The buffer object has to be pinned to %TTM_PL_VRAM. * * Returns: * The buffer object's offset in video memory on success, or * a negative errno code otherwise. */ s64 drm_gem_vram_offset(struct drm_gem_vram_object *gbo) { if (WARN_ON_ONCE(!gbo->bo.pin_count)) return (s64)-ENODEV; return drm_gem_vram_pg_offset(gbo) << PAGE_SHIFT; } EXPORT_SYMBOL(drm_gem_vram_offset); static int drm_gem_vram_pin_locked(struct drm_gem_vram_object *gbo, unsigned long pl_flag) { struct ttm_operation_ctx ctx = { false, false }; int ret; if (gbo->bo.pin_count) goto out; if (pl_flag) drm_gem_vram_placement(gbo, pl_flag); ret = ttm_bo_validate(&gbo->bo, &gbo->placement, &ctx); if (ret < 0) return ret; out: ttm_bo_pin(&gbo->bo); return 0; } /** * drm_gem_vram_pin() - Pins a GEM VRAM object in a region. * @gbo: the GEM VRAM object * @pl_flag: a bitmask of possible memory regions * * Pinning a buffer object ensures that it is not evicted from * a memory region. A pinned buffer object has to be unpinned before * it can be pinned to another region. If the pl_flag argument is 0, * the buffer is pinned at its current location (video RAM or system * memory). * * Small buffer objects, such as cursor images, can lead to memory * fragmentation if they are pinned in the middle of video RAM. This * is especially a problem on devices with only a small amount of * video RAM. Fragmentation can prevent the primary framebuffer from * fitting in, even though there's enough memory overall. The modifier * DRM_GEM_VRAM_PL_FLAG_TOPDOWN marks the buffer object to be pinned * at the high end of the memory region to avoid fragmentation. * * Returns: * 0 on success, or * a negative error code otherwise. */ int drm_gem_vram_pin(struct drm_gem_vram_object *gbo, unsigned long pl_flag) { int ret; ret = ttm_bo_reserve(&gbo->bo, true, false, NULL); if (ret) return ret; ret = drm_gem_vram_pin_locked(gbo, pl_flag); ttm_bo_unreserve(&gbo->bo); return ret; } EXPORT_SYMBOL(drm_gem_vram_pin); static void drm_gem_vram_unpin_locked(struct drm_gem_vram_object *gbo) { ttm_bo_unpin(&gbo->bo); } /** * drm_gem_vram_unpin() - Unpins a GEM VRAM object * @gbo: the GEM VRAM object * * Returns: * 0 on success, or * a negative error code otherwise. */ int drm_gem_vram_unpin(struct drm_gem_vram_object *gbo) { int ret; ret = ttm_bo_reserve(&gbo->bo, true, false, NULL); if (ret) return ret; drm_gem_vram_unpin_locked(gbo); ttm_bo_unreserve(&gbo->bo); return 0; } EXPORT_SYMBOL(drm_gem_vram_unpin); static int drm_gem_vram_kmap_locked(struct drm_gem_vram_object *gbo, struct dma_buf_map *map) { int ret; if (gbo->vmap_use_count > 0) goto out; /* * VRAM helpers unmap the BO only on demand. So the previous * page mapping might still be around. Only vmap if the there's * no mapping present. */ if (dma_buf_map_is_null(&gbo->map)) { ret = ttm_bo_vmap(&gbo->bo, &gbo->map); if (ret) return ret; } out: ++gbo->vmap_use_count; *map = gbo->map; return 0; } static void drm_gem_vram_kunmap_locked(struct drm_gem_vram_object *gbo, struct dma_buf_map *map) { struct drm_device *dev = gbo->bo.base.dev; if (drm_WARN_ON_ONCE(dev, !gbo->vmap_use_count)) return; if (drm_WARN_ON_ONCE(dev, !dma_buf_map_is_equal(&gbo->map, map))) return; /* BUG: map not mapped from this BO */ if (--gbo->vmap_use_count > 0) return; /* * Permanently mapping and unmapping buffers adds overhead from * updating the page tables and creates debugging output. Therefore, * we delay the actual unmap operation until the BO gets evicted * from memory. See drm_gem_vram_bo_driver_move_notify(). */ } /** * drm_gem_vram_vmap() - Pins and maps a GEM VRAM object into kernel address * space * @gbo: The GEM VRAM object to map * @map: Returns the kernel virtual address of the VRAM GEM object's backing * store. * * The vmap function pins a GEM VRAM object to its current location, either * system or video memory, and maps its buffer into kernel address space. * As pinned object cannot be relocated, you should avoid pinning objects * permanently. Call drm_gem_vram_vunmap() with the returned address to * unmap and unpin the GEM VRAM object. * * Returns: * 0 on success, or a negative error code otherwise. */ int drm_gem_vram_vmap(struct drm_gem_vram_object *gbo, struct dma_buf_map *map) { int ret; ret = ttm_bo_reserve(&gbo->bo, true, false, NULL); if (ret) return ret; ret = drm_gem_vram_pin_locked(gbo, 0); if (ret) goto err_ttm_bo_unreserve; ret = drm_gem_vram_kmap_locked(gbo, map); if (ret) goto err_drm_gem_vram_unpin_locked; ttm_bo_unreserve(&gbo->bo); return 0; err_drm_gem_vram_unpin_locked: drm_gem_vram_unpin_locked(gbo); err_ttm_bo_unreserve: ttm_bo_unreserve(&gbo->bo); return ret; } EXPORT_SYMBOL(drm_gem_vram_vmap); /** * drm_gem_vram_vunmap() - Unmaps and unpins a GEM VRAM object * @gbo: The GEM VRAM object to unmap * @map: Kernel virtual address where the VRAM GEM object was mapped * * A call to drm_gem_vram_vunmap() unmaps and unpins a GEM VRAM buffer. See * the documentation for drm_gem_vram_vmap() for more information. */ void drm_gem_vram_vunmap(struct drm_gem_vram_object *gbo, struct dma_buf_map *map) { int ret; ret = ttm_bo_reserve(&gbo->bo, false, false, NULL); if (WARN_ONCE(ret, "ttm_bo_reserve_failed(): ret=%d\n", ret)) return; drm_gem_vram_kunmap_locked(gbo, map); drm_gem_vram_unpin_locked(gbo); ttm_bo_unreserve(&gbo->bo); } EXPORT_SYMBOL(drm_gem_vram_vunmap); /** * drm_gem_vram_fill_create_dumb() - \ Helper for implementing &struct drm_driver.dumb_create * @file: the DRM file * @dev: the DRM device * @pg_align: the buffer's alignment in multiples of the page size * @pitch_align: the scanline's alignment in powers of 2 * @args: the arguments as provided to \ &struct drm_driver.dumb_create * * This helper function fills &struct drm_mode_create_dumb, which is used * by &struct drm_driver.dumb_create. Implementations of this interface * should forwards their arguments to this helper, plus the driver-specific * parameters. * * Returns: * 0 on success, or * a negative error code otherwise. */ int drm_gem_vram_fill_create_dumb(struct drm_file *file, struct drm_device *dev, unsigned long pg_align, unsigned long pitch_align, struct drm_mode_create_dumb *args) { size_t pitch, size; struct drm_gem_vram_object *gbo; int ret; u32 handle; pitch = args->width * DIV_ROUND_UP(args->bpp, 8); if (pitch_align) { if (WARN_ON_ONCE(!is_power_of_2(pitch_align))) return -EINVAL; pitch = ALIGN(pitch, pitch_align); } size = pitch * args->height; size = roundup(size, PAGE_SIZE); if (!size) return -EINVAL; gbo = drm_gem_vram_create(dev, size, pg_align); if (IS_ERR(gbo)) return PTR_ERR(gbo); ret = drm_gem_handle_create(file, &gbo->bo.base, &handle); if (ret) goto err_drm_gem_object_put; drm_gem_object_put(&gbo->bo.base); args->pitch = pitch; args->size = size; args->handle = handle; return 0; err_drm_gem_object_put: drm_gem_object_put(&gbo->bo.base); return ret; } EXPORT_SYMBOL(drm_gem_vram_fill_create_dumb); /* * Helpers for struct ttm_device_funcs */ static bool drm_is_gem_vram(struct ttm_buffer_object *bo) { return (bo->destroy == ttm_buffer_object_destroy); } static void drm_gem_vram_bo_driver_evict_flags(struct drm_gem_vram_object *gbo, struct ttm_placement *pl) { drm_gem_vram_placement(gbo, DRM_GEM_VRAM_PL_FLAG_SYSTEM); *pl = gbo->placement; } static void drm_gem_vram_bo_driver_move_notify(struct drm_gem_vram_object *gbo) { struct ttm_buffer_object *bo = &gbo->bo; struct drm_device *dev = bo->base.dev; if (drm_WARN_ON_ONCE(dev, gbo->vmap_use_count)) return; ttm_bo_vunmap(bo, &gbo->map); dma_buf_map_clear(&gbo->map); /* explicitly clear mapping for next vmap call */ } static int drm_gem_vram_bo_driver_move(struct drm_gem_vram_object *gbo, bool evict, struct ttm_operation_ctx *ctx, struct ttm_resource *new_mem) { drm_gem_vram_bo_driver_move_notify(gbo); return ttm_bo_move_memcpy(&gbo->bo, ctx, new_mem); } /* * Helpers for struct drm_gem_object_funcs */ /** * drm_gem_vram_object_free() - \ Implements &struct drm_gem_object_funcs.free * @gem: GEM object. Refers to &struct drm_gem_vram_object.gem */ static void drm_gem_vram_object_free(struct drm_gem_object *gem) { struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem); drm_gem_vram_put(gbo); } /* * Helpers for dump buffers */ /** * drm_gem_vram_driver_dumb_create() - \ Implements &struct drm_driver.dumb_create * @file: the DRM file * @dev: the DRM device * @args: the arguments as provided to \ &struct drm_driver.dumb_create * * This function requires the driver to use @drm_device.vram_mm for its * instance of VRAM MM. * * Returns: * 0 on success, or * a negative error code otherwise. */ int drm_gem_vram_driver_dumb_create(struct drm_file *file, struct drm_device *dev, struct drm_mode_create_dumb *args) { if (WARN_ONCE(!dev->vram_mm, "VRAM MM not initialized")) return -EINVAL; return drm_gem_vram_fill_create_dumb(file, dev, 0, 0, args); } EXPORT_SYMBOL(drm_gem_vram_driver_dumb_create); /* * Helpers for struct drm_plane_helper_funcs */ /** * drm_gem_vram_plane_helper_prepare_fb() - \ * Implements &struct drm_plane_helper_funcs.prepare_fb * @plane: a DRM plane * @new_state: the plane's new state * * During plane updates, this function sets the plane's fence and * pins the GEM VRAM objects of the plane's new framebuffer to VRAM. * Call drm_gem_vram_plane_helper_cleanup_fb() to unpin them. * * Returns: * 0 on success, or * a negative errno code otherwise. */ int drm_gem_vram_plane_helper_prepare_fb(struct drm_plane *plane, struct drm_plane_state *new_state) { size_t i; struct drm_gem_vram_object *gbo; int ret; if (!new_state->fb) return 0; for (i = 0; i < ARRAY_SIZE(new_state->fb->obj); ++i) { if (!new_state->fb->obj[i]) continue; gbo = drm_gem_vram_of_gem(new_state->fb->obj[i]); ret = drm_gem_vram_pin(gbo, DRM_GEM_VRAM_PL_FLAG_VRAM); if (ret) goto err_drm_gem_vram_unpin; } ret = drm_gem_plane_helper_prepare_fb(plane, new_state); if (ret) goto err_drm_gem_vram_unpin; return 0; err_drm_gem_vram_unpin: while (i) { --i; gbo = drm_gem_vram_of_gem(new_state->fb->obj[i]); drm_gem_vram_unpin(gbo); } return ret; } EXPORT_SYMBOL(drm_gem_vram_plane_helper_prepare_fb); /** * drm_gem_vram_plane_helper_cleanup_fb() - \ * Implements &struct drm_plane_helper_funcs.cleanup_fb * @plane: a DRM plane * @old_state: the plane's old state * * During plane updates, this function unpins the GEM VRAM * objects of the plane's old framebuffer from VRAM. Complements * drm_gem_vram_plane_helper_prepare_fb(). */ void drm_gem_vram_plane_helper_cleanup_fb(struct drm_plane *plane, struct drm_plane_state *old_state) { size_t i; struct drm_gem_vram_object *gbo; if (!old_state->fb) return; for (i = 0; i < ARRAY_SIZE(old_state->fb->obj); ++i) { if (!old_state->fb->obj[i]) continue; gbo = drm_gem_vram_of_gem(old_state->fb->obj[i]); drm_gem_vram_unpin(gbo); } } EXPORT_SYMBOL(drm_gem_vram_plane_helper_cleanup_fb); /* * Helpers for struct drm_simple_display_pipe_funcs */ /** * drm_gem_vram_simple_display_pipe_prepare_fb() - \ * Implements &struct drm_simple_display_pipe_funcs.prepare_fb * @pipe: a simple display pipe * @new_state: the plane's new state * * During plane updates, this function pins the GEM VRAM * objects of the plane's new framebuffer to VRAM. Call * drm_gem_vram_simple_display_pipe_cleanup_fb() to unpin them. * * Returns: * 0 on success, or * a negative errno code otherwise. */ int drm_gem_vram_simple_display_pipe_prepare_fb( struct drm_simple_display_pipe *pipe, struct drm_plane_state *new_state) { return drm_gem_vram_plane_helper_prepare_fb(&pipe->plane, new_state); } EXPORT_SYMBOL(drm_gem_vram_simple_display_pipe_prepare_fb); /** * drm_gem_vram_simple_display_pipe_cleanup_fb() - \ * Implements &struct drm_simple_display_pipe_funcs.cleanup_fb * @pipe: a simple display pipe * @old_state: the plane's old state * * During plane updates, this function unpins the GEM VRAM * objects of the plane's old framebuffer from VRAM. Complements * drm_gem_vram_simple_display_pipe_prepare_fb(). */ void drm_gem_vram_simple_display_pipe_cleanup_fb( struct drm_simple_display_pipe *pipe, struct drm_plane_state *old_state) { drm_gem_vram_plane_helper_cleanup_fb(&pipe->plane, old_state); } EXPORT_SYMBOL(drm_gem_vram_simple_display_pipe_cleanup_fb); /* * PRIME helpers */ /** * drm_gem_vram_object_pin() - \ Implements &struct drm_gem_object_funcs.pin * @gem: The GEM object to pin * * Returns: * 0 on success, or * a negative errno code otherwise. */ static int drm_gem_vram_object_pin(struct drm_gem_object *gem) { struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem); /* Fbdev console emulation is the use case of these PRIME * helpers. This may involve updating a hardware buffer from * a shadow FB. We pin the buffer to it's current location * (either video RAM or system memory) to prevent it from * being relocated during the update operation. If you require * the buffer to be pinned to VRAM, implement a callback that * sets the flags accordingly. */ return drm_gem_vram_pin(gbo, 0); } /** * drm_gem_vram_object_unpin() - \ Implements &struct drm_gem_object_funcs.unpin * @gem: The GEM object to unpin */ static void drm_gem_vram_object_unpin(struct drm_gem_object *gem) { struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem); drm_gem_vram_unpin(gbo); } /** * drm_gem_vram_object_vmap() - * Implements &struct drm_gem_object_funcs.vmap * @gem: The GEM object to map * @map: Returns the kernel virtual address of the VRAM GEM object's backing * store. * * Returns: * 0 on success, or a negative error code otherwise. */ static int drm_gem_vram_object_vmap(struct drm_gem_object *gem, struct dma_buf_map *map) { struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem); return drm_gem_vram_vmap(gbo, map); } /** * drm_gem_vram_object_vunmap() - * Implements &struct drm_gem_object_funcs.vunmap * @gem: The GEM object to unmap * @map: Kernel virtual address where the VRAM GEM object was mapped */ static void drm_gem_vram_object_vunmap(struct drm_gem_object *gem, struct dma_buf_map *map) { struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem); drm_gem_vram_vunmap(gbo, map); } /* * GEM object funcs */ static const struct drm_gem_object_funcs drm_gem_vram_object_funcs = { .free = drm_gem_vram_object_free, .pin = drm_gem_vram_object_pin, .unpin = drm_gem_vram_object_unpin, .vmap = drm_gem_vram_object_vmap, .vunmap = drm_gem_vram_object_vunmap, .mmap = drm_gem_ttm_mmap, .print_info = drm_gem_ttm_print_info, }; /* * VRAM memory manager */ /* * TTM TT */ static void bo_driver_ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *tt) { ttm_tt_destroy_common(bdev, tt); ttm_tt_fini(tt); kfree(tt); } /* * TTM BO device */ static struct ttm_tt *bo_driver_ttm_tt_create(struct ttm_buffer_object *bo, uint32_t page_flags) { struct ttm_tt *tt; int ret; tt = kzalloc(sizeof(*tt), GFP_KERNEL); if (!tt) return NULL; ret = ttm_tt_init(tt, bo, page_flags, ttm_cached); if (ret < 0) goto err_ttm_tt_init; return tt; err_ttm_tt_init: kfree(tt); return NULL; } static void bo_driver_evict_flags(struct ttm_buffer_object *bo, struct ttm_placement *placement) { struct drm_gem_vram_object *gbo; /* TTM may pass BOs that are not GEM VRAM BOs. */ if (!drm_is_gem_vram(bo)) return; gbo = drm_gem_vram_of_bo(bo); drm_gem_vram_bo_driver_evict_flags(gbo, placement); } static void bo_driver_delete_mem_notify(struct ttm_buffer_object *bo) { struct drm_gem_vram_object *gbo; /* TTM may pass BOs that are not GEM VRAM BOs. */ if (!drm_is_gem_vram(bo)) return; gbo = drm_gem_vram_of_bo(bo); drm_gem_vram_bo_driver_move_notify(gbo); } static int bo_driver_move(struct ttm_buffer_object *bo, bool evict, struct ttm_operation_ctx *ctx, struct ttm_resource *new_mem, struct ttm_place *hop) { struct drm_gem_vram_object *gbo; gbo = drm_gem_vram_of_bo(bo); return drm_gem_vram_bo_driver_move(gbo, evict, ctx, new_mem); } static int bo_driver_io_mem_reserve(struct ttm_device *bdev, struct ttm_resource *mem) { struct drm_vram_mm *vmm = drm_vram_mm_of_bdev(bdev); switch (mem->mem_type) { case TTM_PL_SYSTEM: /* nothing to do */ break; case TTM_PL_VRAM: mem->bus.offset = (mem->start << PAGE_SHIFT) + vmm->vram_base; mem->bus.is_iomem = true; mem->bus.caching = ttm_write_combined; break; default: return -EINVAL; } return 0; } static struct ttm_device_funcs bo_driver = { .ttm_tt_create = bo_driver_ttm_tt_create, .ttm_tt_destroy = bo_driver_ttm_tt_destroy, .eviction_valuable = ttm_bo_eviction_valuable, .evict_flags = bo_driver_evict_flags, .move = bo_driver_move, .delete_mem_notify = bo_driver_delete_mem_notify, .io_mem_reserve = bo_driver_io_mem_reserve, }; /* * struct drm_vram_mm */ static int drm_vram_mm_debugfs(struct seq_file *m, void *data) { struct drm_info_node *node = (struct drm_info_node *) m->private; struct drm_vram_mm *vmm = node->minor->dev->vram_mm; struct ttm_resource_manager *man = ttm_manager_type(&vmm->bdev, TTM_PL_VRAM); struct drm_printer p = drm_seq_file_printer(m); ttm_resource_manager_debug(man, &p); return 0; } static const struct drm_info_list drm_vram_mm_debugfs_list[] = { { "vram-mm", drm_vram_mm_debugfs, 0, NULL }, }; /** * drm_vram_mm_debugfs_init() - Register VRAM MM debugfs file. * * @minor: drm minor device. * */ void drm_vram_mm_debugfs_init(struct drm_minor *minor) { drm_debugfs_create_files(drm_vram_mm_debugfs_list, ARRAY_SIZE(drm_vram_mm_debugfs_list), minor->debugfs_root, minor); } EXPORT_SYMBOL(drm_vram_mm_debugfs_init); static int drm_vram_mm_init(struct drm_vram_mm *vmm, struct drm_device *dev, uint64_t vram_base, size_t vram_size) { int ret; vmm->vram_base = vram_base; vmm->vram_size = vram_size; ret = ttm_device_init(&vmm->bdev, &bo_driver, dev->dev, dev->anon_inode->i_mapping, dev->vma_offset_manager, false, true); if (ret) return ret; ret = ttm_range_man_init(&vmm->bdev, TTM_PL_VRAM, false, vram_size >> PAGE_SHIFT); if (ret) return ret; return 0; } static void drm_vram_mm_cleanup(struct drm_vram_mm *vmm) { ttm_range_man_fini(&vmm->bdev, TTM_PL_VRAM); ttm_device_fini(&vmm->bdev); } /* * Helpers for integration with struct drm_device */ /* deprecated; use drmm_vram_mm_init() */ struct drm_vram_mm *drm_vram_helper_alloc_mm( struct drm_device *dev, uint64_t vram_base, size_t vram_size) { int ret; if (WARN_ON(dev->vram_mm)) return dev->vram_mm; dev->vram_mm = kzalloc(sizeof(*dev->vram_mm), GFP_KERNEL); if (!dev->vram_mm) return ERR_PTR(-ENOMEM); ret = drm_vram_mm_init(dev->vram_mm, dev, vram_base, vram_size); if (ret) goto err_kfree; return dev->vram_mm; err_kfree: kfree(dev->vram_mm); dev->vram_mm = NULL; return ERR_PTR(ret); } EXPORT_SYMBOL(drm_vram_helper_alloc_mm); void drm_vram_helper_release_mm(struct drm_device *dev) { if (!dev->vram_mm) return; drm_vram_mm_cleanup(dev->vram_mm); kfree(dev->vram_mm); dev->vram_mm = NULL; } EXPORT_SYMBOL(drm_vram_helper_release_mm); static void drm_vram_mm_release(struct drm_device *dev, void *ptr) { drm_vram_helper_release_mm(dev); } /** * drmm_vram_helper_init - Initializes a device's instance of * &struct drm_vram_mm * @dev: the DRM device * @vram_base: the base address of the video memory * @vram_size: the size of the video memory in bytes * * Creates a new instance of &struct drm_vram_mm and stores it in * struct &drm_device.vram_mm. The instance is auto-managed and cleaned * up as part of device cleanup. Calling this function multiple times * will generate an error message. * * Returns: * 0 on success, or a negative errno code otherwise. */ int drmm_vram_helper_init(struct drm_device *dev, uint64_t vram_base, size_t vram_size) { struct drm_vram_mm *vram_mm; if (drm_WARN_ON_ONCE(dev, dev->vram_mm)) return 0; vram_mm = drm_vram_helper_alloc_mm(dev, vram_base, vram_size); if (IS_ERR(vram_mm)) return PTR_ERR(vram_mm); return drmm_add_action_or_reset(dev, drm_vram_mm_release, NULL); } EXPORT_SYMBOL(drmm_vram_helper_init); /* * Mode-config helpers */ static enum drm_mode_status drm_vram_helper_mode_valid_internal(struct drm_device *dev, const struct drm_display_mode *mode, unsigned long max_bpp) { struct drm_vram_mm *vmm = dev->vram_mm; unsigned long fbsize, fbpages, max_fbpages; if (WARN_ON(!dev->vram_mm)) return MODE_BAD; max_fbpages = (vmm->vram_size / 2) >> PAGE_SHIFT; fbsize = mode->hdisplay * mode->vdisplay * max_bpp; fbpages = DIV_ROUND_UP(fbsize, PAGE_SIZE); if (fbpages > max_fbpages) return MODE_MEM; return MODE_OK; } /** * drm_vram_helper_mode_valid - Tests if a display mode's * framebuffer fits into the available video memory. * @dev: the DRM device * @mode: the mode to test * * This function tests if enough video memory is available for using the * specified display mode. Atomic modesetting requires importing the * designated framebuffer into video memory before evicting the active * one. Hence, any framebuffer may consume at most half of the available * VRAM. Display modes that require a larger framebuffer can not be used, * even if the CRTC does support them. Each framebuffer is assumed to * have 32-bit color depth. * * Note: * The function can only test if the display mode is supported in * general. If there are too many framebuffers pinned to video memory, * a display mode may still not be usable in practice. The color depth of * 32-bit fits all current use case. A more flexible test can be added * when necessary. * * Returns: * MODE_OK if the display mode is supported, or an error code of type * enum drm_mode_status otherwise. */ enum drm_mode_status drm_vram_helper_mode_valid(struct drm_device *dev, const struct drm_display_mode *mode) { static const unsigned long max_bpp = 4; /* DRM_FORMAT_XRGB8888 */ return drm_vram_helper_mode_valid_internal(dev, mode, max_bpp); } EXPORT_SYMBOL(drm_vram_helper_mode_valid); MODULE_DESCRIPTION("DRM VRAM memory-management helpers"); MODULE_LICENSE("GPL");