// SPDX-License-Identifier: GPL-2.0-or-later #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. * * The easiest way to use the VRAM helper library is to call * drm_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 = drm_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. * * To clean up the VRAM memory management, call drm_vram_helper_release_mm() * in the driver's clean-up code. * * .. code-block:: c * * void fini_drm_driver() * { * struct drm_device *dev = ...; * * drm_vram_helper_release_mm(dev); * } * * For drawing or scanout operations, buffer object 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_kmap(). It (optionally) maps the buffer into kernel address * space and returns the memory address. Use drm_gem_vram_kunmap() 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->kmap_use_count); WARN_ON(gbo->kmap.virtual); 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) { unsigned int i; unsigned int c = 0; u32 invariant_flags = pl_flag & TTM_PL_FLAG_TOPDOWN; gbo->placement.placement = gbo->placements; gbo->placement.busy_placement = gbo->placements; if (pl_flag & TTM_PL_FLAG_VRAM) gbo->placements[c++].flags = TTM_PL_FLAG_WC | TTM_PL_FLAG_UNCACHED | TTM_PL_FLAG_VRAM | invariant_flags; if (pl_flag & TTM_PL_FLAG_SYSTEM) gbo->placements[c++].flags = TTM_PL_MASK_CACHING | TTM_PL_FLAG_SYSTEM | invariant_flags; if (!c) gbo->placements[c++].flags = TTM_PL_MASK_CACHING | TTM_PL_FLAG_SYSTEM | 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; } } static int drm_gem_vram_init(struct drm_device *dev, struct drm_gem_vram_object *gbo, size_t size, unsigned long pg_align) { struct drm_vram_mm *vmm = dev->vram_mm; struct ttm_bo_device *bdev; int ret; size_t acc_size; if (WARN_ONCE(!vmm, "VRAM MM not initialized")) return -EINVAL; bdev = &vmm->bdev; gbo->bo.base.funcs = &drm_gem_vram_object_funcs; ret = drm_gem_object_init(dev, &gbo->bo.base, size); if (ret) return ret; acc_size = ttm_bo_dma_acc_size(bdev, size, sizeof(*gbo)); gbo->bo.bdev = bdev; drm_gem_vram_placement(gbo, TTM_PL_FLAG_VRAM | TTM_PL_FLAG_SYSTEM); ret = ttm_bo_init(bdev, &gbo->bo, size, ttm_bo_type_device, &gbo->placement, pg_align, false, acc_size, NULL, NULL, ttm_buffer_object_destroy); if (ret) goto err_drm_gem_object_release; return 0; err_drm_gem_object_release: drm_gem_object_release(&gbo->bo.base); return ret; } /** * 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 * * 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; int ret; if (dev->driver->gem_create_object) { struct drm_gem_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); } ret = drm_gem_vram_init(dev, gbo, size, pg_align); if (ret < 0) goto err_kfree; return gbo; err_kfree: kfree(gbo); return ERR_PTR(ret); } 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); /** * drm_gem_vram_mmap_offset() - Returns a GEM VRAM object's mmap offset * @gbo: the GEM VRAM object * * See drm_vma_node_offset_addr() for more information. * * Returns: * The buffer object's offset for userspace mappings on success, or * 0 if no offset is allocated. */ u64 drm_gem_vram_mmap_offset(struct drm_gem_vram_object *gbo) { return drm_vma_node_offset_addr(&gbo->bo.base.vma_node); } EXPORT_SYMBOL(drm_gem_vram_mmap_offset); 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.mem.mm_node)) return 0; return gbo->bo.mem.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->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) { int i, ret; struct ttm_operation_ctx ctx = { false, false }; if (gbo->pin_count) goto out; if (pl_flag) drm_gem_vram_placement(gbo, pl_flag); for (i = 0; i < gbo->placement.num_placement; ++i) gbo->placements[i].flags |= TTM_PL_FLAG_NO_EVICT; ret = ttm_bo_validate(&gbo->bo, &gbo->placement, &ctx); if (ret < 0) return ret; out: ++gbo->pin_count; 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 int drm_gem_vram_unpin_locked(struct drm_gem_vram_object *gbo) { int i, ret; struct ttm_operation_ctx ctx = { false, false }; if (WARN_ON_ONCE(!gbo->pin_count)) return 0; --gbo->pin_count; if (gbo->pin_count) return 0; for (i = 0; i < gbo->placement.num_placement ; ++i) gbo->placements[i].flags &= ~TTM_PL_FLAG_NO_EVICT; ret = ttm_bo_validate(&gbo->bo, &gbo->placement, &ctx); if (ret < 0) return ret; return 0; } /** * 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; ret = drm_gem_vram_unpin_locked(gbo); ttm_bo_unreserve(&gbo->bo); return ret; } EXPORT_SYMBOL(drm_gem_vram_unpin); static void *drm_gem_vram_kmap_locked(struct drm_gem_vram_object *gbo, bool map, bool *is_iomem) { int ret; struct ttm_bo_kmap_obj *kmap = &gbo->kmap; if (gbo->kmap_use_count > 0) goto out; if (kmap->virtual || !map) goto out; ret = ttm_bo_kmap(&gbo->bo, 0, gbo->bo.num_pages, kmap); if (ret) return ERR_PTR(ret); out: if (!kmap->virtual) { if (is_iomem) *is_iomem = false; return NULL; /* not mapped; don't increment ref */ } ++gbo->kmap_use_count; if (is_iomem) return ttm_kmap_obj_virtual(kmap, is_iomem); return kmap->virtual; } /** * drm_gem_vram_kmap() - Maps a GEM VRAM object into kernel address space * @gbo: the GEM VRAM object * @map: establish a mapping if necessary * @is_iomem: returns true if the mapped memory is I/O memory, or false \ otherwise; can be NULL * * This function maps the buffer object into the kernel's address space * or returns the current mapping. If the parameter map is false, the * function only queries the current mapping, but does not establish a * new one. * * Returns: * The buffers virtual address if mapped, or * NULL if not mapped, or * an ERR_PTR()-encoded error code otherwise. */ void *drm_gem_vram_kmap(struct drm_gem_vram_object *gbo, bool map, bool *is_iomem) { int ret; void *virtual; ret = ttm_bo_reserve(&gbo->bo, true, false, NULL); if (ret) return ERR_PTR(ret); virtual = drm_gem_vram_kmap_locked(gbo, map, is_iomem); ttm_bo_unreserve(&gbo->bo); return virtual; } EXPORT_SYMBOL(drm_gem_vram_kmap); static void drm_gem_vram_kunmap_locked(struct drm_gem_vram_object *gbo) { if (WARN_ON_ONCE(!gbo->kmap_use_count)) return; if (--gbo->kmap_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_kunmap() - Unmaps a GEM VRAM object * @gbo: the GEM VRAM object */ void drm_gem_vram_kunmap(struct drm_gem_vram_object *gbo) { 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); ttm_bo_unreserve(&gbo->bo); } EXPORT_SYMBOL(drm_gem_vram_kunmap); /** * drm_gem_vram_vmap() - Pins and maps a GEM VRAM object into kernel address * space * @gbo: The GEM VRAM object to map * * 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. * * If you have special requirements for the pinning or mapping operations, * call drm_gem_vram_pin() and drm_gem_vram_kmap() directly. * * Returns: * The buffer's virtual address on success, or * an ERR_PTR()-encoded error code otherwise. */ void *drm_gem_vram_vmap(struct drm_gem_vram_object *gbo) { int ret; void *base; ret = ttm_bo_reserve(&gbo->bo, true, false, NULL); if (ret) return ERR_PTR(ret); ret = drm_gem_vram_pin_locked(gbo, 0); if (ret) goto err_ttm_bo_unreserve; base = drm_gem_vram_kmap_locked(gbo, true, NULL); if (IS_ERR(base)) { ret = PTR_ERR(base); goto err_drm_gem_vram_unpin_locked; } ttm_bo_unreserve(&gbo->bo); return base; err_drm_gem_vram_unpin_locked: drm_gem_vram_unpin_locked(gbo); err_ttm_bo_unreserve: ttm_bo_unreserve(&gbo->bo); return ERR_PTR(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 * @vaddr: The mapping's base address as returned by drm_gem_vram_vmap() * * 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, void *vaddr) { 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); 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_bo_driver */ 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, TTM_PL_FLAG_SYSTEM); *pl = gbo->placement; } static void drm_gem_vram_bo_driver_move_notify(struct drm_gem_vram_object *gbo, bool evict, struct ttm_mem_reg *new_mem) { struct ttm_bo_kmap_obj *kmap = &gbo->kmap; if (WARN_ON_ONCE(gbo->kmap_use_count)) return; if (!kmap->virtual) return; ttm_bo_kunmap(kmap); kmap->virtual = NULL; } /* * 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_create_dumb() - \ 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); /** * drm_gem_vram_driver_dumb_mmap_offset() - \ Implements &struct drm_driver.dumb_mmap_offset * @file: DRM file pointer. * @dev: DRM device. * @handle: GEM handle * @offset: Returns the mapping's memory offset on success * * Returns: * 0 on success, or * a negative errno code otherwise. */ int drm_gem_vram_driver_dumb_mmap_offset(struct drm_file *file, struct drm_device *dev, uint32_t handle, uint64_t *offset) { struct drm_gem_object *gem; struct drm_gem_vram_object *gbo; gem = drm_gem_object_lookup(file, handle); if (!gem) return -ENOENT; gbo = drm_gem_vram_of_gem(gem); *offset = drm_gem_vram_mmap_offset(gbo); drm_gem_object_put(gem); return 0; } EXPORT_SYMBOL(drm_gem_vram_driver_dumb_mmap_offset); /* * 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_fb_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 * * Returns: * The buffers virtual address on success, or * NULL otherwise. */ static void *drm_gem_vram_object_vmap(struct drm_gem_object *gem) { struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem); void *base; base = drm_gem_vram_vmap(gbo); if (IS_ERR(base)) return NULL; return base; } /** * drm_gem_vram_object_vunmap() - \ Implements &struct drm_gem_object_funcs.vunmap * @gem: The GEM object to unmap * @vaddr: The mapping's base address */ static void drm_gem_vram_object_vunmap(struct drm_gem_object *gem, void *vaddr) { struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem); drm_gem_vram_vunmap(gbo, vaddr); } /* * 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 backend_func_destroy(struct ttm_tt *tt) { ttm_tt_fini(tt); kfree(tt); } static struct ttm_backend_func backend_func = { .destroy = backend_func_destroy }; /* * 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; tt->func = &backend_func; ret = ttm_tt_init(tt, bo, page_flags); if (ret < 0) goto err_ttm_tt_init; return tt; err_ttm_tt_init: kfree(tt); return NULL; } static int bo_driver_init_mem_type(struct ttm_bo_device *bdev, uint32_t type, struct ttm_mem_type_manager *man) { switch (type) { case TTM_PL_SYSTEM: man->flags = TTM_MEMTYPE_FLAG_MAPPABLE; man->available_caching = TTM_PL_MASK_CACHING; man->default_caching = TTM_PL_FLAG_CACHED; break; case TTM_PL_VRAM: man->func = &ttm_bo_manager_func; man->flags = TTM_MEMTYPE_FLAG_FIXED | TTM_MEMTYPE_FLAG_MAPPABLE; man->available_caching = TTM_PL_FLAG_UNCACHED | TTM_PL_FLAG_WC; man->default_caching = TTM_PL_FLAG_WC; break; default: return -EINVAL; } return 0; } 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_move_notify(struct ttm_buffer_object *bo, bool evict, struct ttm_mem_reg *new_mem) { 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, evict, new_mem); } static int bo_driver_io_mem_reserve(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem) { struct ttm_mem_type_manager *man = bdev->man + mem->mem_type; struct drm_vram_mm *vmm = drm_vram_mm_of_bdev(bdev); if (!(man->flags & TTM_MEMTYPE_FLAG_MAPPABLE)) return -EINVAL; mem->bus.addr = NULL; mem->bus.size = mem->num_pages << PAGE_SHIFT; switch (mem->mem_type) { case TTM_PL_SYSTEM: /* nothing to do */ mem->bus.offset = 0; mem->bus.base = 0; mem->bus.is_iomem = false; break; case TTM_PL_VRAM: mem->bus.offset = mem->start << PAGE_SHIFT; mem->bus.base = vmm->vram_base; mem->bus.is_iomem = true; break; default: return -EINVAL; } return 0; } static void bo_driver_io_mem_free(struct ttm_bo_device *bdev, struct ttm_mem_reg *mem) { } static struct ttm_bo_driver bo_driver = { .ttm_tt_create = bo_driver_ttm_tt_create, .ttm_tt_populate = ttm_pool_populate, .ttm_tt_unpopulate = ttm_pool_unpopulate, .init_mem_type = bo_driver_init_mem_type, .eviction_valuable = ttm_bo_eviction_valuable, .evict_flags = bo_driver_evict_flags, .move_notify = bo_driver_move_notify, .io_mem_reserve = bo_driver_io_mem_reserve, .io_mem_free = bo_driver_io_mem_free, }; /* * 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 drm_mm *mm = vmm->bdev.man[TTM_PL_VRAM].priv; struct drm_printer p = drm_seq_file_printer(m); spin_lock(&ttm_bo_glob.lru_lock); drm_mm_print(mm, &p); spin_unlock(&ttm_bo_glob.lru_lock); 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_bo_device_init(&vmm->bdev, &bo_driver, dev->anon_inode->i_mapping, dev->vma_offset_manager, true); if (ret) return ret; ret = ttm_bo_init_mm(&vmm->bdev, TTM_PL_VRAM, vram_size >> PAGE_SHIFT); if (ret) return ret; return 0; } static void drm_vram_mm_cleanup(struct drm_vram_mm *vmm) { ttm_bo_device_release(&vmm->bdev); } /* * Helpers for integration with struct drm_device */ /** * drm_vram_helper_alloc_mm - Allocates 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 * * Returns: * The new instance of &struct drm_vram_mm on success, or * an ERR_PTR()-encoded errno code otherwise. */ 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); /** * drm_vram_helper_release_mm - Releases a device's instance of \ &struct drm_vram_mm * @dev: the DRM device */ 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); /* * 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");