1 // SPDX-License-Identifier: GPL-2.0-or-later
3 #include <linux/module.h>
5 #include <drm/drm_debugfs.h>
6 #include <drm/drm_device.h>
7 #include <drm/drm_drv.h>
8 #include <drm/drm_file.h>
9 #include <drm/drm_framebuffer.h>
10 #include <drm/drm_gem_framebuffer_helper.h>
11 #include <drm/drm_gem_ttm_helper.h>
12 #include <drm/drm_gem_vram_helper.h>
13 #include <drm/drm_mode.h>
14 #include <drm/drm_plane.h>
15 #include <drm/drm_prime.h>
16 #include <drm/drm_simple_kms_helper.h>
17 #include <drm/ttm/ttm_page_alloc.h>
19 static const struct drm_gem_object_funcs drm_gem_vram_object_funcs;
24 * This library provides &struct drm_gem_vram_object (GEM VRAM), a GEM
25 * buffer object that is backed by video RAM (VRAM). It can be used for
26 * framebuffer devices with dedicated memory.
28 * The data structure &struct drm_vram_mm and its helpers implement a memory
29 * manager for simple framebuffer devices with dedicated video memory. GEM
30 * VRAM buffer objects are either placed in the video memory or remain evicted
33 * With the GEM interface userspace applications create, manage and destroy
34 * graphics buffers, such as an on-screen framebuffer. GEM does not provide
35 * an implementation of these interfaces. It's up to the DRM driver to
36 * provide an implementation that suits the hardware. If the hardware device
37 * contains dedicated video memory, the DRM driver can use the VRAM helper
38 * library. Each active buffer object is stored in video RAM. Active
39 * buffer are used for drawing the current frame, typically something like
40 * the frame's scanout buffer or the cursor image. If there's no more space
41 * left in VRAM, inactive GEM objects can be moved to system memory.
43 * The easiest way to use the VRAM helper library is to call
44 * drm_vram_helper_alloc_mm(). The function allocates and initializes an
45 * instance of &struct drm_vram_mm in &struct drm_device.vram_mm . Use
46 * &DRM_GEM_VRAM_DRIVER to initialize &struct drm_driver and
47 * &DRM_VRAM_MM_FILE_OPERATIONS to initialize &struct file_operations;
48 * as illustrated below.
52 * struct file_operations fops ={
53 * .owner = THIS_MODULE,
54 * DRM_VRAM_MM_FILE_OPERATION
56 * struct drm_driver drv = {
57 * .driver_feature = DRM_ ... ,
62 * int init_drm_driver()
64 * struct drm_device *dev;
66 * unsigned long vram_size;
69 * // setup device, vram base and size
72 * ret = drm_vram_helper_alloc_mm(dev, vram_base, vram_size);
78 * This creates an instance of &struct drm_vram_mm, exports DRM userspace
79 * interfaces for GEM buffer management and initializes file operations to
80 * allow for accessing created GEM buffers. With this setup, the DRM driver
81 * manages an area of video RAM with VRAM MM and provides GEM VRAM objects
84 * To clean up the VRAM memory management, call drm_vram_helper_release_mm()
85 * in the driver's clean-up code.
89 * void fini_drm_driver()
91 * struct drm_device *dev = ...;
93 * drm_vram_helper_release_mm(dev);
96 * For drawing or scanout operations, buffer object have to be pinned in video
97 * RAM. Call drm_gem_vram_pin() with &DRM_GEM_VRAM_PL_FLAG_VRAM or
98 * &DRM_GEM_VRAM_PL_FLAG_SYSTEM to pin a buffer object in video RAM or system
99 * memory. Call drm_gem_vram_unpin() to release the pinned object afterwards.
101 * A buffer object that is pinned in video RAM has a fixed address within that
102 * memory region. Call drm_gem_vram_offset() to retrieve this value. Typically
103 * it's used to program the hardware's scanout engine for framebuffers, set
104 * the cursor overlay's image for a mouse cursor, or use it as input to the
105 * hardware's draing engine.
107 * To access a buffer object's memory from the DRM driver, call
108 * drm_gem_vram_kmap(). It (optionally) maps the buffer into kernel address
109 * space and returns the memory address. Use drm_gem_vram_kunmap() to
110 * release the mapping.
114 * Buffer-objects helpers
117 static void drm_gem_vram_cleanup(struct drm_gem_vram_object *gbo)
119 /* We got here via ttm_bo_put(), which means that the
120 * TTM buffer object in 'bo' has already been cleaned
121 * up; only release the GEM object.
124 WARN_ON(gbo->kmap_use_count);
125 WARN_ON(gbo->kmap.virtual);
127 drm_gem_object_release(&gbo->bo.base);
130 static void drm_gem_vram_destroy(struct drm_gem_vram_object *gbo)
132 drm_gem_vram_cleanup(gbo);
136 static void ttm_buffer_object_destroy(struct ttm_buffer_object *bo)
138 struct drm_gem_vram_object *gbo = drm_gem_vram_of_bo(bo);
140 drm_gem_vram_destroy(gbo);
143 static void drm_gem_vram_placement(struct drm_gem_vram_object *gbo,
144 unsigned long pl_flag)
148 u32 invariant_flags = pl_flag & TTM_PL_FLAG_TOPDOWN;
150 gbo->placement.placement = gbo->placements;
151 gbo->placement.busy_placement = gbo->placements;
153 if (pl_flag & TTM_PL_FLAG_VRAM)
154 gbo->placements[c++].flags = TTM_PL_FLAG_WC |
155 TTM_PL_FLAG_UNCACHED |
159 if (pl_flag & TTM_PL_FLAG_SYSTEM)
160 gbo->placements[c++].flags = TTM_PL_MASK_CACHING |
165 gbo->placements[c++].flags = TTM_PL_MASK_CACHING |
169 gbo->placement.num_placement = c;
170 gbo->placement.num_busy_placement = c;
172 for (i = 0; i < c; ++i) {
173 gbo->placements[i].fpfn = 0;
174 gbo->placements[i].lpfn = 0;
178 static int drm_gem_vram_init(struct drm_device *dev,
179 struct drm_gem_vram_object *gbo,
180 size_t size, unsigned long pg_align)
182 struct drm_vram_mm *vmm = dev->vram_mm;
183 struct ttm_bo_device *bdev;
187 if (WARN_ONCE(!vmm, "VRAM MM not initialized"))
191 gbo->bo.base.funcs = &drm_gem_vram_object_funcs;
193 ret = drm_gem_object_init(dev, &gbo->bo.base, size);
197 acc_size = ttm_bo_dma_acc_size(bdev, size, sizeof(*gbo));
200 drm_gem_vram_placement(gbo, TTM_PL_FLAG_VRAM | TTM_PL_FLAG_SYSTEM);
202 ret = ttm_bo_init(bdev, &gbo->bo, size, ttm_bo_type_device,
203 &gbo->placement, pg_align, false, acc_size,
204 NULL, NULL, ttm_buffer_object_destroy);
206 goto err_drm_gem_object_release;
210 err_drm_gem_object_release:
211 drm_gem_object_release(&gbo->bo.base);
216 * drm_gem_vram_create() - Creates a VRAM-backed GEM object
217 * @dev: the DRM device
218 * @size: the buffer size in bytes
219 * @pg_align: the buffer's alignment in multiples of the page size
222 * A new instance of &struct drm_gem_vram_object on success, or
223 * an ERR_PTR()-encoded error code otherwise.
225 struct drm_gem_vram_object *drm_gem_vram_create(struct drm_device *dev,
227 unsigned long pg_align)
229 struct drm_gem_vram_object *gbo;
232 if (dev->driver->gem_create_object) {
233 struct drm_gem_object *gem =
234 dev->driver->gem_create_object(dev, size);
236 return ERR_PTR(-ENOMEM);
237 gbo = drm_gem_vram_of_gem(gem);
239 gbo = kzalloc(sizeof(*gbo), GFP_KERNEL);
241 return ERR_PTR(-ENOMEM);
244 ret = drm_gem_vram_init(dev, gbo, size, pg_align);
254 EXPORT_SYMBOL(drm_gem_vram_create);
257 * drm_gem_vram_put() - Releases a reference to a VRAM-backed GEM object
258 * @gbo: the GEM VRAM object
260 * See ttm_bo_put() for more information.
262 void drm_gem_vram_put(struct drm_gem_vram_object *gbo)
264 ttm_bo_put(&gbo->bo);
266 EXPORT_SYMBOL(drm_gem_vram_put);
269 * drm_gem_vram_mmap_offset() - Returns a GEM VRAM object's mmap offset
270 * @gbo: the GEM VRAM object
272 * See drm_vma_node_offset_addr() for more information.
275 * The buffer object's offset for userspace mappings on success, or
276 * 0 if no offset is allocated.
278 u64 drm_gem_vram_mmap_offset(struct drm_gem_vram_object *gbo)
280 return drm_vma_node_offset_addr(&gbo->bo.base.vma_node);
282 EXPORT_SYMBOL(drm_gem_vram_mmap_offset);
285 * drm_gem_vram_offset() - \
286 Returns a GEM VRAM object's offset in video memory
287 * @gbo: the GEM VRAM object
289 * This function returns the buffer object's offset in the device's video
290 * memory. The buffer object has to be pinned to %TTM_PL_VRAM.
293 * The buffer object's offset in video memory on success, or
294 * a negative errno code otherwise.
296 s64 drm_gem_vram_offset(struct drm_gem_vram_object *gbo)
298 if (WARN_ON_ONCE(!gbo->pin_count))
300 return gbo->bo.offset;
302 EXPORT_SYMBOL(drm_gem_vram_offset);
304 static int drm_gem_vram_pin_locked(struct drm_gem_vram_object *gbo,
305 unsigned long pl_flag)
308 struct ttm_operation_ctx ctx = { false, false };
314 drm_gem_vram_placement(gbo, pl_flag);
316 for (i = 0; i < gbo->placement.num_placement; ++i)
317 gbo->placements[i].flags |= TTM_PL_FLAG_NO_EVICT;
319 ret = ttm_bo_validate(&gbo->bo, &gbo->placement, &ctx);
330 * drm_gem_vram_pin() - Pins a GEM VRAM object in a region.
331 * @gbo: the GEM VRAM object
332 * @pl_flag: a bitmask of possible memory regions
334 * Pinning a buffer object ensures that it is not evicted from
335 * a memory region. A pinned buffer object has to be unpinned before
336 * it can be pinned to another region. If the pl_flag argument is 0,
337 * the buffer is pinned at its current location (video RAM or system
340 * Small buffer objects, such as cursor images, can lead to memory
341 * fragmentation if they are pinned in the middle of video RAM. This
342 * is especially a problem on devices with only a small amount of
343 * video RAM. Fragmentation can prevent the primary framebuffer from
344 * fitting in, even though there's enough memory overall. The modifier
345 * DRM_GEM_VRAM_PL_FLAG_TOPDOWN marks the buffer object to be pinned
346 * at the high end of the memory region to avoid fragmentation.
350 * a negative error code otherwise.
352 int drm_gem_vram_pin(struct drm_gem_vram_object *gbo, unsigned long pl_flag)
356 ret = ttm_bo_reserve(&gbo->bo, true, false, NULL);
359 ret = drm_gem_vram_pin_locked(gbo, pl_flag);
360 ttm_bo_unreserve(&gbo->bo);
364 EXPORT_SYMBOL(drm_gem_vram_pin);
366 static int drm_gem_vram_unpin_locked(struct drm_gem_vram_object *gbo)
369 struct ttm_operation_ctx ctx = { false, false };
371 if (WARN_ON_ONCE(!gbo->pin_count))
378 for (i = 0; i < gbo->placement.num_placement ; ++i)
379 gbo->placements[i].flags &= ~TTM_PL_FLAG_NO_EVICT;
381 ret = ttm_bo_validate(&gbo->bo, &gbo->placement, &ctx);
389 * drm_gem_vram_unpin() - Unpins a GEM VRAM object
390 * @gbo: the GEM VRAM object
394 * a negative error code otherwise.
396 int drm_gem_vram_unpin(struct drm_gem_vram_object *gbo)
400 ret = ttm_bo_reserve(&gbo->bo, true, false, NULL);
403 ret = drm_gem_vram_unpin_locked(gbo);
404 ttm_bo_unreserve(&gbo->bo);
408 EXPORT_SYMBOL(drm_gem_vram_unpin);
410 static void *drm_gem_vram_kmap_locked(struct drm_gem_vram_object *gbo,
411 bool map, bool *is_iomem)
414 struct ttm_bo_kmap_obj *kmap = &gbo->kmap;
416 if (gbo->kmap_use_count > 0)
419 if (kmap->virtual || !map)
422 ret = ttm_bo_kmap(&gbo->bo, 0, gbo->bo.num_pages, kmap);
427 if (!kmap->virtual) {
430 return NULL; /* not mapped; don't increment ref */
432 ++gbo->kmap_use_count;
434 return ttm_kmap_obj_virtual(kmap, is_iomem);
435 return kmap->virtual;
439 * drm_gem_vram_kmap() - Maps a GEM VRAM object into kernel address space
440 * @gbo: the GEM VRAM object
441 * @map: establish a mapping if necessary
442 * @is_iomem: returns true if the mapped memory is I/O memory, or false \
443 otherwise; can be NULL
445 * This function maps the buffer object into the kernel's address space
446 * or returns the current mapping. If the parameter map is false, the
447 * function only queries the current mapping, but does not establish a
451 * The buffers virtual address if mapped, or
452 * NULL if not mapped, or
453 * an ERR_PTR()-encoded error code otherwise.
455 void *drm_gem_vram_kmap(struct drm_gem_vram_object *gbo, bool map,
461 ret = ttm_bo_reserve(&gbo->bo, true, false, NULL);
464 virtual = drm_gem_vram_kmap_locked(gbo, map, is_iomem);
465 ttm_bo_unreserve(&gbo->bo);
469 EXPORT_SYMBOL(drm_gem_vram_kmap);
471 static void drm_gem_vram_kunmap_locked(struct drm_gem_vram_object *gbo)
473 if (WARN_ON_ONCE(!gbo->kmap_use_count))
475 if (--gbo->kmap_use_count > 0)
479 * Permanently mapping and unmapping buffers adds overhead from
480 * updating the page tables and creates debugging output. Therefore,
481 * we delay the actual unmap operation until the BO gets evicted
482 * from memory. See drm_gem_vram_bo_driver_move_notify().
487 * drm_gem_vram_kunmap() - Unmaps a GEM VRAM object
488 * @gbo: the GEM VRAM object
490 void drm_gem_vram_kunmap(struct drm_gem_vram_object *gbo)
494 ret = ttm_bo_reserve(&gbo->bo, false, false, NULL);
495 if (WARN_ONCE(ret, "ttm_bo_reserve_failed(): ret=%d\n", ret))
497 drm_gem_vram_kunmap_locked(gbo);
498 ttm_bo_unreserve(&gbo->bo);
500 EXPORT_SYMBOL(drm_gem_vram_kunmap);
503 * drm_gem_vram_vmap() - Pins and maps a GEM VRAM object into kernel address
505 * @gbo: The GEM VRAM object to map
507 * The vmap function pins a GEM VRAM object to its current location, either
508 * system or video memory, and maps its buffer into kernel address space.
509 * As pinned object cannot be relocated, you should avoid pinning objects
510 * permanently. Call drm_gem_vram_vunmap() with the returned address to
511 * unmap and unpin the GEM VRAM object.
513 * If you have special requirements for the pinning or mapping operations,
514 * call drm_gem_vram_pin() and drm_gem_vram_kmap() directly.
517 * The buffer's virtual address on success, or
518 * an ERR_PTR()-encoded error code otherwise.
520 void *drm_gem_vram_vmap(struct drm_gem_vram_object *gbo)
525 ret = ttm_bo_reserve(&gbo->bo, true, false, NULL);
529 ret = drm_gem_vram_pin_locked(gbo, 0);
531 goto err_ttm_bo_unreserve;
532 base = drm_gem_vram_kmap_locked(gbo, true, NULL);
535 goto err_drm_gem_vram_unpin_locked;
538 ttm_bo_unreserve(&gbo->bo);
542 err_drm_gem_vram_unpin_locked:
543 drm_gem_vram_unpin_locked(gbo);
544 err_ttm_bo_unreserve:
545 ttm_bo_unreserve(&gbo->bo);
548 EXPORT_SYMBOL(drm_gem_vram_vmap);
551 * drm_gem_vram_vunmap() - Unmaps and unpins a GEM VRAM object
552 * @gbo: The GEM VRAM object to unmap
553 * @vaddr: The mapping's base address as returned by drm_gem_vram_vmap()
555 * A call to drm_gem_vram_vunmap() unmaps and unpins a GEM VRAM buffer. See
556 * the documentation for drm_gem_vram_vmap() for more information.
558 void drm_gem_vram_vunmap(struct drm_gem_vram_object *gbo, void *vaddr)
562 ret = ttm_bo_reserve(&gbo->bo, false, false, NULL);
563 if (WARN_ONCE(ret, "ttm_bo_reserve_failed(): ret=%d\n", ret))
566 drm_gem_vram_kunmap_locked(gbo);
567 drm_gem_vram_unpin_locked(gbo);
569 ttm_bo_unreserve(&gbo->bo);
571 EXPORT_SYMBOL(drm_gem_vram_vunmap);
574 * drm_gem_vram_fill_create_dumb() - \
575 Helper for implementing &struct drm_driver.dumb_create
576 * @file: the DRM file
577 * @dev: the DRM device
578 * @pg_align: the buffer's alignment in multiples of the page size
579 * @pitch_align: the scanline's alignment in powers of 2
580 * @args: the arguments as provided to \
581 &struct drm_driver.dumb_create
583 * This helper function fills &struct drm_mode_create_dumb, which is used
584 * by &struct drm_driver.dumb_create. Implementations of this interface
585 * should forwards their arguments to this helper, plus the driver-specific
590 * a negative error code otherwise.
592 int drm_gem_vram_fill_create_dumb(struct drm_file *file,
593 struct drm_device *dev,
594 unsigned long pg_align,
595 unsigned long pitch_align,
596 struct drm_mode_create_dumb *args)
599 struct drm_gem_vram_object *gbo;
603 pitch = args->width * DIV_ROUND_UP(args->bpp, 8);
605 if (WARN_ON_ONCE(!is_power_of_2(pitch_align)))
607 pitch = ALIGN(pitch, pitch_align);
609 size = pitch * args->height;
611 size = roundup(size, PAGE_SIZE);
615 gbo = drm_gem_vram_create(dev, size, pg_align);
619 ret = drm_gem_handle_create(file, &gbo->bo.base, &handle);
621 goto err_drm_gem_object_put_unlocked;
623 drm_gem_object_put_unlocked(&gbo->bo.base);
627 args->handle = handle;
631 err_drm_gem_object_put_unlocked:
632 drm_gem_object_put_unlocked(&gbo->bo.base);
635 EXPORT_SYMBOL(drm_gem_vram_fill_create_dumb);
638 * Helpers for struct ttm_bo_driver
641 static bool drm_is_gem_vram(struct ttm_buffer_object *bo)
643 return (bo->destroy == ttm_buffer_object_destroy);
646 static void drm_gem_vram_bo_driver_evict_flags(struct drm_gem_vram_object *gbo,
647 struct ttm_placement *pl)
649 drm_gem_vram_placement(gbo, TTM_PL_FLAG_SYSTEM);
650 *pl = gbo->placement;
653 static void drm_gem_vram_bo_driver_move_notify(struct drm_gem_vram_object *gbo,
655 struct ttm_mem_reg *new_mem)
657 struct ttm_bo_kmap_obj *kmap = &gbo->kmap;
659 if (WARN_ON_ONCE(gbo->kmap_use_count))
665 kmap->virtual = NULL;
669 * Helpers for struct drm_gem_object_funcs
673 * drm_gem_vram_object_free() - \
674 Implements &struct drm_gem_object_funcs.free
675 * @gem: GEM object. Refers to &struct drm_gem_vram_object.gem
677 static void drm_gem_vram_object_free(struct drm_gem_object *gem)
679 struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem);
681 drm_gem_vram_put(gbo);
685 * Helpers for dump buffers
689 * drm_gem_vram_driver_create_dumb() - \
690 Implements &struct drm_driver.dumb_create
691 * @file: the DRM file
692 * @dev: the DRM device
693 * @args: the arguments as provided to \
694 &struct drm_driver.dumb_create
696 * This function requires the driver to use @drm_device.vram_mm for its
697 * instance of VRAM MM.
701 * a negative error code otherwise.
703 int drm_gem_vram_driver_dumb_create(struct drm_file *file,
704 struct drm_device *dev,
705 struct drm_mode_create_dumb *args)
707 if (WARN_ONCE(!dev->vram_mm, "VRAM MM not initialized"))
710 return drm_gem_vram_fill_create_dumb(file, dev, 0, 0, args);
712 EXPORT_SYMBOL(drm_gem_vram_driver_dumb_create);
715 * drm_gem_vram_driver_dumb_mmap_offset() - \
716 Implements &struct drm_driver.dumb_mmap_offset
717 * @file: DRM file pointer.
719 * @handle: GEM handle
720 * @offset: Returns the mapping's memory offset on success
724 * a negative errno code otherwise.
726 int drm_gem_vram_driver_dumb_mmap_offset(struct drm_file *file,
727 struct drm_device *dev,
728 uint32_t handle, uint64_t *offset)
730 struct drm_gem_object *gem;
731 struct drm_gem_vram_object *gbo;
733 gem = drm_gem_object_lookup(file, handle);
737 gbo = drm_gem_vram_of_gem(gem);
738 *offset = drm_gem_vram_mmap_offset(gbo);
740 drm_gem_object_put_unlocked(gem);
744 EXPORT_SYMBOL(drm_gem_vram_driver_dumb_mmap_offset);
747 * Helpers for struct drm_plane_helper_funcs
751 * drm_gem_vram_plane_helper_prepare_fb() - \
752 * Implements &struct drm_plane_helper_funcs.prepare_fb
753 * @plane: a DRM plane
754 * @new_state: the plane's new state
756 * During plane updates, this function sets the plane's fence and
757 * pins the GEM VRAM objects of the plane's new framebuffer to VRAM.
758 * Call drm_gem_vram_plane_helper_cleanup_fb() to unpin them.
762 * a negative errno code otherwise.
765 drm_gem_vram_plane_helper_prepare_fb(struct drm_plane *plane,
766 struct drm_plane_state *new_state)
769 struct drm_gem_vram_object *gbo;
775 for (i = 0; i < ARRAY_SIZE(new_state->fb->obj); ++i) {
776 if (!new_state->fb->obj[i])
778 gbo = drm_gem_vram_of_gem(new_state->fb->obj[i]);
779 ret = drm_gem_vram_pin(gbo, DRM_GEM_VRAM_PL_FLAG_VRAM);
781 goto err_drm_gem_vram_unpin;
784 ret = drm_gem_fb_prepare_fb(plane, new_state);
786 goto err_drm_gem_vram_unpin;
790 err_drm_gem_vram_unpin:
793 gbo = drm_gem_vram_of_gem(new_state->fb->obj[i]);
794 drm_gem_vram_unpin(gbo);
798 EXPORT_SYMBOL(drm_gem_vram_plane_helper_prepare_fb);
801 * drm_gem_vram_plane_helper_cleanup_fb() - \
802 * Implements &struct drm_plane_helper_funcs.cleanup_fb
803 * @plane: a DRM plane
804 * @old_state: the plane's old state
806 * During plane updates, this function unpins the GEM VRAM
807 * objects of the plane's old framebuffer from VRAM. Complements
808 * drm_gem_vram_plane_helper_prepare_fb().
811 drm_gem_vram_plane_helper_cleanup_fb(struct drm_plane *plane,
812 struct drm_plane_state *old_state)
815 struct drm_gem_vram_object *gbo;
820 for (i = 0; i < ARRAY_SIZE(old_state->fb->obj); ++i) {
821 if (!old_state->fb->obj[i])
823 gbo = drm_gem_vram_of_gem(old_state->fb->obj[i]);
824 drm_gem_vram_unpin(gbo);
827 EXPORT_SYMBOL(drm_gem_vram_plane_helper_cleanup_fb);
830 * Helpers for struct drm_simple_display_pipe_funcs
834 * drm_gem_vram_simple_display_pipe_prepare_fb() - \
835 * Implements &struct drm_simple_display_pipe_funcs.prepare_fb
836 * @pipe: a simple display pipe
837 * @new_state: the plane's new state
839 * During plane updates, this function pins the GEM VRAM
840 * objects of the plane's new framebuffer to VRAM. Call
841 * drm_gem_vram_simple_display_pipe_cleanup_fb() to unpin them.
845 * a negative errno code otherwise.
847 int drm_gem_vram_simple_display_pipe_prepare_fb(
848 struct drm_simple_display_pipe *pipe,
849 struct drm_plane_state *new_state)
851 return drm_gem_vram_plane_helper_prepare_fb(&pipe->plane, new_state);
853 EXPORT_SYMBOL(drm_gem_vram_simple_display_pipe_prepare_fb);
856 * drm_gem_vram_simple_display_pipe_cleanup_fb() - \
857 * Implements &struct drm_simple_display_pipe_funcs.cleanup_fb
858 * @pipe: a simple display pipe
859 * @old_state: the plane's old state
861 * During plane updates, this function unpins the GEM VRAM
862 * objects of the plane's old framebuffer from VRAM. Complements
863 * drm_gem_vram_simple_display_pipe_prepare_fb().
865 void drm_gem_vram_simple_display_pipe_cleanup_fb(
866 struct drm_simple_display_pipe *pipe,
867 struct drm_plane_state *old_state)
869 drm_gem_vram_plane_helper_cleanup_fb(&pipe->plane, old_state);
871 EXPORT_SYMBOL(drm_gem_vram_simple_display_pipe_cleanup_fb);
878 * drm_gem_vram_object_pin() - \
879 Implements &struct drm_gem_object_funcs.pin
880 * @gem: The GEM object to pin
884 * a negative errno code otherwise.
886 static int drm_gem_vram_object_pin(struct drm_gem_object *gem)
888 struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem);
890 /* Fbdev console emulation is the use case of these PRIME
891 * helpers. This may involve updating a hardware buffer from
892 * a shadow FB. We pin the buffer to it's current location
893 * (either video RAM or system memory) to prevent it from
894 * being relocated during the update operation. If you require
895 * the buffer to be pinned to VRAM, implement a callback that
896 * sets the flags accordingly.
898 return drm_gem_vram_pin(gbo, 0);
902 * drm_gem_vram_object_unpin() - \
903 Implements &struct drm_gem_object_funcs.unpin
904 * @gem: The GEM object to unpin
906 static void drm_gem_vram_object_unpin(struct drm_gem_object *gem)
908 struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem);
910 drm_gem_vram_unpin(gbo);
914 * drm_gem_vram_object_vmap() - \
915 Implements &struct drm_gem_object_funcs.vmap
916 * @gem: The GEM object to map
919 * The buffers virtual address on success, or
922 static void *drm_gem_vram_object_vmap(struct drm_gem_object *gem)
924 struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem);
927 base = drm_gem_vram_vmap(gbo);
934 * drm_gem_vram_object_vunmap() - \
935 Implements &struct drm_gem_object_funcs.vunmap
936 * @gem: The GEM object to unmap
937 * @vaddr: The mapping's base address
939 static void drm_gem_vram_object_vunmap(struct drm_gem_object *gem,
942 struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem);
944 drm_gem_vram_vunmap(gbo, vaddr);
951 static const struct drm_gem_object_funcs drm_gem_vram_object_funcs = {
952 .free = drm_gem_vram_object_free,
953 .pin = drm_gem_vram_object_pin,
954 .unpin = drm_gem_vram_object_unpin,
955 .vmap = drm_gem_vram_object_vmap,
956 .vunmap = drm_gem_vram_object_vunmap,
957 .mmap = drm_gem_ttm_mmap,
958 .print_info = drm_gem_ttm_print_info,
962 * VRAM memory manager
969 static void backend_func_destroy(struct ttm_tt *tt)
975 static struct ttm_backend_func backend_func = {
976 .destroy = backend_func_destroy
983 static struct ttm_tt *bo_driver_ttm_tt_create(struct ttm_buffer_object *bo,
989 tt = kzalloc(sizeof(*tt), GFP_KERNEL);
993 tt->func = &backend_func;
995 ret = ttm_tt_init(tt, bo, page_flags);
997 goto err_ttm_tt_init;
1006 static int bo_driver_init_mem_type(struct ttm_bo_device *bdev, uint32_t type,
1007 struct ttm_mem_type_manager *man)
1011 man->flags = TTM_MEMTYPE_FLAG_MAPPABLE;
1012 man->available_caching = TTM_PL_MASK_CACHING;
1013 man->default_caching = TTM_PL_FLAG_CACHED;
1016 man->func = &ttm_bo_manager_func;
1017 man->flags = TTM_MEMTYPE_FLAG_FIXED |
1018 TTM_MEMTYPE_FLAG_MAPPABLE;
1019 man->available_caching = TTM_PL_FLAG_UNCACHED |
1021 man->default_caching = TTM_PL_FLAG_WC;
1029 static void bo_driver_evict_flags(struct ttm_buffer_object *bo,
1030 struct ttm_placement *placement)
1032 struct drm_gem_vram_object *gbo;
1034 /* TTM may pass BOs that are not GEM VRAM BOs. */
1035 if (!drm_is_gem_vram(bo))
1038 gbo = drm_gem_vram_of_bo(bo);
1040 drm_gem_vram_bo_driver_evict_flags(gbo, placement);
1043 static void bo_driver_move_notify(struct ttm_buffer_object *bo,
1045 struct ttm_mem_reg *new_mem)
1047 struct drm_gem_vram_object *gbo;
1049 /* TTM may pass BOs that are not GEM VRAM BOs. */
1050 if (!drm_is_gem_vram(bo))
1053 gbo = drm_gem_vram_of_bo(bo);
1055 drm_gem_vram_bo_driver_move_notify(gbo, evict, new_mem);
1058 static int bo_driver_io_mem_reserve(struct ttm_bo_device *bdev,
1059 struct ttm_mem_reg *mem)
1061 struct ttm_mem_type_manager *man = bdev->man + mem->mem_type;
1062 struct drm_vram_mm *vmm = drm_vram_mm_of_bdev(bdev);
1064 if (!(man->flags & TTM_MEMTYPE_FLAG_MAPPABLE))
1067 mem->bus.addr = NULL;
1068 mem->bus.size = mem->num_pages << PAGE_SHIFT;
1070 switch (mem->mem_type) {
1071 case TTM_PL_SYSTEM: /* nothing to do */
1072 mem->bus.offset = 0;
1074 mem->bus.is_iomem = false;
1077 mem->bus.offset = mem->start << PAGE_SHIFT;
1078 mem->bus.base = vmm->vram_base;
1079 mem->bus.is_iomem = true;
1088 static void bo_driver_io_mem_free(struct ttm_bo_device *bdev,
1089 struct ttm_mem_reg *mem)
1092 static struct ttm_bo_driver bo_driver = {
1093 .ttm_tt_create = bo_driver_ttm_tt_create,
1094 .ttm_tt_populate = ttm_pool_populate,
1095 .ttm_tt_unpopulate = ttm_pool_unpopulate,
1096 .init_mem_type = bo_driver_init_mem_type,
1097 .eviction_valuable = ttm_bo_eviction_valuable,
1098 .evict_flags = bo_driver_evict_flags,
1099 .move_notify = bo_driver_move_notify,
1100 .io_mem_reserve = bo_driver_io_mem_reserve,
1101 .io_mem_free = bo_driver_io_mem_free,
1105 * struct drm_vram_mm
1108 static int drm_vram_mm_debugfs(struct seq_file *m, void *data)
1110 struct drm_info_node *node = (struct drm_info_node *) m->private;
1111 struct drm_vram_mm *vmm = node->minor->dev->vram_mm;
1112 struct drm_mm *mm = vmm->bdev.man[TTM_PL_VRAM].priv;
1113 struct drm_printer p = drm_seq_file_printer(m);
1115 spin_lock(&ttm_bo_glob.lru_lock);
1116 drm_mm_print(mm, &p);
1117 spin_unlock(&ttm_bo_glob.lru_lock);
1121 static const struct drm_info_list drm_vram_mm_debugfs_list[] = {
1122 { "vram-mm", drm_vram_mm_debugfs, 0, NULL },
1126 * drm_vram_mm_debugfs_init() - Register VRAM MM debugfs file.
1128 * @minor: drm minor device.
1131 void drm_vram_mm_debugfs_init(struct drm_minor *minor)
1133 drm_debugfs_create_files(drm_vram_mm_debugfs_list,
1134 ARRAY_SIZE(drm_vram_mm_debugfs_list),
1135 minor->debugfs_root, minor);
1137 EXPORT_SYMBOL(drm_vram_mm_debugfs_init);
1139 static int drm_vram_mm_init(struct drm_vram_mm *vmm, struct drm_device *dev,
1140 uint64_t vram_base, size_t vram_size)
1144 vmm->vram_base = vram_base;
1145 vmm->vram_size = vram_size;
1147 ret = ttm_bo_device_init(&vmm->bdev, &bo_driver,
1148 dev->anon_inode->i_mapping,
1149 dev->vma_offset_manager,
1154 ret = ttm_bo_init_mm(&vmm->bdev, TTM_PL_VRAM, vram_size >> PAGE_SHIFT);
1161 static void drm_vram_mm_cleanup(struct drm_vram_mm *vmm)
1163 ttm_bo_device_release(&vmm->bdev);
1167 * Helpers for integration with struct drm_device
1171 * drm_vram_helper_alloc_mm - Allocates a device's instance of \
1173 * @dev: the DRM device
1174 * @vram_base: the base address of the video memory
1175 * @vram_size: the size of the video memory in bytes
1178 * The new instance of &struct drm_vram_mm on success, or
1179 * an ERR_PTR()-encoded errno code otherwise.
1181 struct drm_vram_mm *drm_vram_helper_alloc_mm(
1182 struct drm_device *dev, uint64_t vram_base, size_t vram_size)
1186 if (WARN_ON(dev->vram_mm))
1187 return dev->vram_mm;
1189 dev->vram_mm = kzalloc(sizeof(*dev->vram_mm), GFP_KERNEL);
1191 return ERR_PTR(-ENOMEM);
1193 ret = drm_vram_mm_init(dev->vram_mm, dev, vram_base, vram_size);
1197 return dev->vram_mm;
1200 kfree(dev->vram_mm);
1201 dev->vram_mm = NULL;
1202 return ERR_PTR(ret);
1204 EXPORT_SYMBOL(drm_vram_helper_alloc_mm);
1207 * drm_vram_helper_release_mm - Releases a device's instance of \
1209 * @dev: the DRM device
1211 void drm_vram_helper_release_mm(struct drm_device *dev)
1216 drm_vram_mm_cleanup(dev->vram_mm);
1217 kfree(dev->vram_mm);
1218 dev->vram_mm = NULL;
1220 EXPORT_SYMBOL(drm_vram_helper_release_mm);
1223 * Mode-config helpers
1226 static enum drm_mode_status
1227 drm_vram_helper_mode_valid_internal(struct drm_device *dev,
1228 const struct drm_display_mode *mode,
1229 unsigned long max_bpp)
1231 struct drm_vram_mm *vmm = dev->vram_mm;
1232 unsigned long fbsize, fbpages, max_fbpages;
1234 if (WARN_ON(!dev->vram_mm))
1237 max_fbpages = (vmm->vram_size / 2) >> PAGE_SHIFT;
1239 fbsize = mode->hdisplay * mode->vdisplay * max_bpp;
1240 fbpages = DIV_ROUND_UP(fbsize, PAGE_SIZE);
1242 if (fbpages > max_fbpages)
1249 * drm_vram_helper_mode_valid - Tests if a display mode's
1250 * framebuffer fits into the available video memory.
1251 * @dev: the DRM device
1252 * @mode: the mode to test
1254 * This function tests if enough video memory is available for using the
1255 * specified display mode. Atomic modesetting requires importing the
1256 * designated framebuffer into video memory before evicting the active
1257 * one. Hence, any framebuffer may consume at most half of the available
1258 * VRAM. Display modes that require a larger framebuffer can not be used,
1259 * even if the CRTC does support them. Each framebuffer is assumed to
1260 * have 32-bit color depth.
1263 * The function can only test if the display mode is supported in
1264 * general. If there are too many framebuffers pinned to video memory,
1265 * a display mode may still not be usable in practice. The color depth of
1266 * 32-bit fits all current use case. A more flexible test can be added
1270 * MODE_OK if the display mode is supported, or an error code of type
1271 * enum drm_mode_status otherwise.
1273 enum drm_mode_status
1274 drm_vram_helper_mode_valid(struct drm_device *dev,
1275 const struct drm_display_mode *mode)
1277 static const unsigned long max_bpp = 4; /* DRM_FORMAT_XRGB8888 */
1279 return drm_vram_helper_mode_valid_internal(dev, mode, max_bpp);
1281 EXPORT_SYMBOL(drm_vram_helper_mode_valid);
1283 MODULE_DESCRIPTION("DRM VRAM memory-management helpers");
1284 MODULE_LICENSE("GPL");