diff options
Diffstat (limited to 'drivers/gpu/drm/drm_gem_vram_helper.c')
| -rw-r--r-- | drivers/gpu/drm/drm_gem_vram_helper.c | 1162 |
1 files changed, 1162 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_gem_vram_helper.c b/drivers/gpu/drm/drm_gem_vram_helper.c new file mode 100644 index 000000000..928e08e0b --- /dev/null +++ b/drivers/gpu/drm/drm_gem_vram_helper.c @@ -0,0 +1,1162 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <linux/iosys-map.h> +#include <linux/module.h> + +#include <drm/drm_debugfs.h> +#include <drm/drm_device.h> +#include <drm/drm_drv.h> +#include <drm/drm_file.h> +#include <drm/drm_framebuffer.h> +#include <drm/drm_gem_atomic_helper.h> +#include <drm/drm_gem_framebuffer_helper.h> +#include <drm/drm_gem_ttm_helper.h> +#include <drm/drm_gem_vram_helper.h> +#include <drm/drm_managed.h> +#include <drm/drm_mode.h> +#include <drm/drm_plane.h> +#include <drm/drm_prime.h> +#include <drm/drm_simple_kms_helper.h> + +#include <drm/ttm/ttm_range_manager.h> + +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_init(). + * 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_init(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_init() 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 drawing 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(iosys_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 (IS_ERR(gem)) + return ERR_CAST(gem); + 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_validate(bdev, &gbo->bo, 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 || + gbo->bo.resource->mem_type == TTM_PL_SYSTEM)) + 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 iosys_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 (iosys_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 iosys_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, !iosys_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 iosys_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 iosys_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); + iosys_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 + */ + +static void __drm_gem_vram_plane_helper_cleanup_fb(struct drm_plane *plane, + struct drm_plane_state *state, + unsigned int num_planes) +{ + struct drm_gem_object *obj; + struct drm_gem_vram_object *gbo; + struct drm_framebuffer *fb = state->fb; + + while (num_planes) { + --num_planes; + obj = drm_gem_fb_get_obj(fb, num_planes); + if (!obj) + continue; + gbo = drm_gem_vram_of_gem(obj); + drm_gem_vram_unpin(gbo); + } +} + +/** + * 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) +{ + struct drm_framebuffer *fb = new_state->fb; + struct drm_gem_vram_object *gbo; + struct drm_gem_object *obj; + unsigned int i; + int ret; + + if (!fb) + return 0; + + 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_vram_unpin; + } + gbo = drm_gem_vram_of_gem(obj); + 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: + __drm_gem_vram_plane_helper_cleanup_fb(plane, new_state, i); + 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) +{ + struct drm_framebuffer *fb = old_state->fb; + + if (!fb) + return; + + __drm_gem_vram_plane_helper_cleanup_fb(plane, old_state, fb->format->num_planes); +} +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 iosys_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 iosys_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_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, 0); + 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 + */ + +static 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); +} + +static 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; +} + +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"); |