1 // SPDX-License-Identifier: GPL-2.0-or-later
3 #include <drm/drm_gem_vram_helper.h>
4 #include <drm/drm_device.h>
5 #include <drm/drm_mode.h>
6 #include <drm/drm_prime.h>
7 #include <drm/drm_vram_mm_helper.h>
8 #include <drm/ttm/ttm_page_alloc.h>
13 * This library provides a GEM buffer object that is backed by video RAM
14 * (VRAM). It can be used for framebuffer devices with dedicated memory.
18 * Buffer-objects helpers
21 static void drm_gem_vram_cleanup(struct drm_gem_vram_object
*gbo
)
23 /* We got here via ttm_bo_put(), which means that the
24 * TTM buffer object in 'bo' has already been cleaned
25 * up; only release the GEM object.
27 drm_gem_object_release(&gbo
->gem
);
30 static void drm_gem_vram_destroy(struct drm_gem_vram_object
*gbo
)
32 drm_gem_vram_cleanup(gbo
);
36 static void ttm_buffer_object_destroy(struct ttm_buffer_object
*bo
)
38 struct drm_gem_vram_object
*gbo
= drm_gem_vram_of_bo(bo
);
40 drm_gem_vram_destroy(gbo
);
43 static void drm_gem_vram_placement(struct drm_gem_vram_object
*gbo
,
44 unsigned long pl_flag
)
49 gbo
->placement
.placement
= gbo
->placements
;
50 gbo
->placement
.busy_placement
= gbo
->placements
;
52 if (pl_flag
& TTM_PL_FLAG_VRAM
)
53 gbo
->placements
[c
++].flags
= TTM_PL_FLAG_WC
|
54 TTM_PL_FLAG_UNCACHED
|
57 if (pl_flag
& TTM_PL_FLAG_SYSTEM
)
58 gbo
->placements
[c
++].flags
= TTM_PL_MASK_CACHING
|
62 gbo
->placements
[c
++].flags
= TTM_PL_MASK_CACHING
|
65 gbo
->placement
.num_placement
= c
;
66 gbo
->placement
.num_busy_placement
= c
;
68 for (i
= 0; i
< c
; ++i
) {
69 gbo
->placements
[i
].fpfn
= 0;
70 gbo
->placements
[i
].lpfn
= 0;
74 static int drm_gem_vram_init(struct drm_device
*dev
,
75 struct ttm_bo_device
*bdev
,
76 struct drm_gem_vram_object
*gbo
,
77 size_t size
, unsigned long pg_align
,
83 ret
= drm_gem_object_init(dev
, &gbo
->gem
, size
);
87 acc_size
= ttm_bo_dma_acc_size(bdev
, size
, sizeof(*gbo
));
90 drm_gem_vram_placement(gbo
, TTM_PL_FLAG_VRAM
| TTM_PL_FLAG_SYSTEM
);
92 ret
= ttm_bo_init(bdev
, &gbo
->bo
, size
, ttm_bo_type_device
,
93 &gbo
->placement
, pg_align
, interruptible
, acc_size
,
94 NULL
, NULL
, ttm_buffer_object_destroy
);
96 goto err_drm_gem_object_release
;
100 err_drm_gem_object_release
:
101 drm_gem_object_release(&gbo
->gem
);
106 * drm_gem_vram_create() - Creates a VRAM-backed GEM object
107 * @dev: the DRM device
108 * @bdev: the TTM BO device backing the object
109 * @size: the buffer size in bytes
110 * @pg_align: the buffer's alignment in multiples of the page size
111 * @interruptible: sleep interruptible if waiting for memory
114 * A new instance of &struct drm_gem_vram_object on success, or
115 * an ERR_PTR()-encoded error code otherwise.
117 struct drm_gem_vram_object
*drm_gem_vram_create(struct drm_device
*dev
,
118 struct ttm_bo_device
*bdev
,
120 unsigned long pg_align
,
123 struct drm_gem_vram_object
*gbo
;
126 gbo
= kzalloc(sizeof(*gbo
), GFP_KERNEL
);
128 return ERR_PTR(-ENOMEM
);
130 ret
= drm_gem_vram_init(dev
, bdev
, gbo
, size
, pg_align
, interruptible
);
140 EXPORT_SYMBOL(drm_gem_vram_create
);
143 * drm_gem_vram_put() - Releases a reference to a VRAM-backed GEM object
144 * @gbo: the GEM VRAM object
146 * See ttm_bo_put() for more information.
148 void drm_gem_vram_put(struct drm_gem_vram_object
*gbo
)
150 ttm_bo_put(&gbo
->bo
);
152 EXPORT_SYMBOL(drm_gem_vram_put
);
155 * drm_gem_vram_mmap_offset() - Returns a GEM VRAM object's mmap offset
156 * @gbo: the GEM VRAM object
158 * See drm_vma_node_offset_addr() for more information.
161 * The buffer object's offset for userspace mappings on success, or
162 * 0 if no offset is allocated.
164 u64
drm_gem_vram_mmap_offset(struct drm_gem_vram_object
*gbo
)
166 return drm_vma_node_offset_addr(&gbo
->bo
.vma_node
);
168 EXPORT_SYMBOL(drm_gem_vram_mmap_offset
);
171 * drm_gem_vram_offset() - \
172 Returns a GEM VRAM object's offset in video memory
173 * @gbo: the GEM VRAM object
175 * This function returns the buffer object's offset in the device's video
176 * memory. The buffer object has to be pinned to %TTM_PL_VRAM.
179 * The buffer object's offset in video memory on success, or
180 * a negative errno code otherwise.
182 s64
drm_gem_vram_offset(struct drm_gem_vram_object
*gbo
)
184 if (WARN_ON_ONCE(!gbo
->pin_count
))
186 return gbo
->bo
.offset
;
188 EXPORT_SYMBOL(drm_gem_vram_offset
);
191 * drm_gem_vram_pin() - Pins a GEM VRAM object in a region.
192 * @gbo: the GEM VRAM object
193 * @pl_flag: a bitmask of possible memory regions
195 * Pinning a buffer object ensures that it is not evicted from
196 * a memory region. A pinned buffer object has to be unpinned before
197 * it can be pinned to another region. If the pl_flag argument is 0,
198 * the buffer is pinned at its current location (video RAM or system
203 * a negative error code otherwise.
205 int drm_gem_vram_pin(struct drm_gem_vram_object
*gbo
, unsigned long pl_flag
)
208 struct ttm_operation_ctx ctx
= { false, false };
210 ret
= ttm_bo_reserve(&gbo
->bo
, true, false, NULL
);
218 drm_gem_vram_placement(gbo
, pl_flag
);
220 for (i
= 0; i
< gbo
->placement
.num_placement
; ++i
)
221 gbo
->placements
[i
].flags
|= TTM_PL_FLAG_NO_EVICT
;
223 ret
= ttm_bo_validate(&gbo
->bo
, &gbo
->placement
, &ctx
);
225 goto err_ttm_bo_unreserve
;
229 ttm_bo_unreserve(&gbo
->bo
);
233 err_ttm_bo_unreserve
:
234 ttm_bo_unreserve(&gbo
->bo
);
237 EXPORT_SYMBOL(drm_gem_vram_pin
);
240 * drm_gem_vram_unpin() - Unpins a GEM VRAM object
241 * @gbo: the GEM VRAM object
245 * a negative error code otherwise.
247 int drm_gem_vram_unpin(struct drm_gem_vram_object
*gbo
)
250 struct ttm_operation_ctx ctx
= { false, false };
252 ret
= ttm_bo_reserve(&gbo
->bo
, true, false, NULL
);
256 if (WARN_ON_ONCE(!gbo
->pin_count
))
263 for (i
= 0; i
< gbo
->placement
.num_placement
; ++i
)
264 gbo
->placements
[i
].flags
&= ~TTM_PL_FLAG_NO_EVICT
;
266 ret
= ttm_bo_validate(&gbo
->bo
, &gbo
->placement
, &ctx
);
268 goto err_ttm_bo_unreserve
;
271 ttm_bo_unreserve(&gbo
->bo
);
275 err_ttm_bo_unreserve
:
276 ttm_bo_unreserve(&gbo
->bo
);
279 EXPORT_SYMBOL(drm_gem_vram_unpin
);
282 * drm_gem_vram_kmap() - Maps a GEM VRAM object into kernel address space
283 * @gbo: the GEM VRAM object
284 * @map: establish a mapping if necessary
285 * @is_iomem: returns true if the mapped memory is I/O memory, or false \
286 otherwise; can be NULL
288 * This function maps the buffer object into the kernel's address space
289 * or returns the current mapping. If the parameter map is false, the
290 * function only queries the current mapping, but does not establish a
294 * The buffers virtual address if mapped, or
295 * NULL if not mapped, or
296 * an ERR_PTR()-encoded error code otherwise.
298 void *drm_gem_vram_kmap(struct drm_gem_vram_object
*gbo
, bool map
,
302 struct ttm_bo_kmap_obj
*kmap
= &gbo
->kmap
;
304 if (kmap
->virtual || !map
)
307 ret
= ttm_bo_kmap(&gbo
->bo
, 0, gbo
->bo
.num_pages
, kmap
);
313 return kmap
->virtual;
314 if (!kmap
->virtual) {
318 return ttm_kmap_obj_virtual(kmap
, is_iomem
);
320 EXPORT_SYMBOL(drm_gem_vram_kmap
);
323 * drm_gem_vram_kunmap() - Unmaps a GEM VRAM object
324 * @gbo: the GEM VRAM object
326 void drm_gem_vram_kunmap(struct drm_gem_vram_object
*gbo
)
328 struct ttm_bo_kmap_obj
*kmap
= &gbo
->kmap
;
334 kmap
->virtual = NULL
;
336 EXPORT_SYMBOL(drm_gem_vram_kunmap
);
339 * drm_gem_vram_fill_create_dumb() - \
340 Helper for implementing &struct drm_driver.dumb_create
341 * @file: the DRM file
342 * @dev: the DRM device
343 * @bdev: the TTM BO device managing the buffer object
344 * @pg_align: the buffer's alignment in multiples of the page size
345 * @interruptible: sleep interruptible if waiting for memory
346 * @args: the arguments as provided to \
347 &struct drm_driver.dumb_create
349 * This helper function fills &struct drm_mode_create_dumb, which is used
350 * by &struct drm_driver.dumb_create. Implementations of this interface
351 * should forwards their arguments to this helper, plus the driver-specific
356 * a negative error code otherwise.
358 int drm_gem_vram_fill_create_dumb(struct drm_file
*file
,
359 struct drm_device
*dev
,
360 struct ttm_bo_device
*bdev
,
361 unsigned long pg_align
,
363 struct drm_mode_create_dumb
*args
)
366 struct drm_gem_vram_object
*gbo
;
370 pitch
= args
->width
* ((args
->bpp
+ 7) / 8);
371 size
= pitch
* args
->height
;
373 size
= roundup(size
, PAGE_SIZE
);
377 gbo
= drm_gem_vram_create(dev
, bdev
, size
, pg_align
, interruptible
);
381 ret
= drm_gem_handle_create(file
, &gbo
->gem
, &handle
);
383 goto err_drm_gem_object_put_unlocked
;
385 drm_gem_object_put_unlocked(&gbo
->gem
);
389 args
->handle
= handle
;
393 err_drm_gem_object_put_unlocked
:
394 drm_gem_object_put_unlocked(&gbo
->gem
);
397 EXPORT_SYMBOL(drm_gem_vram_fill_create_dumb
);
400 * Helpers for struct ttm_bo_driver
403 static bool drm_is_gem_vram(struct ttm_buffer_object
*bo
)
405 return (bo
->destroy
== ttm_buffer_object_destroy
);
409 * drm_gem_vram_bo_driver_evict_flags() - \
410 Implements &struct ttm_bo_driver.evict_flags
411 * @bo: TTM buffer object. Refers to &struct drm_gem_vram_object.bo
412 * @pl: TTM placement information.
414 void drm_gem_vram_bo_driver_evict_flags(struct ttm_buffer_object
*bo
,
415 struct ttm_placement
*pl
)
417 struct drm_gem_vram_object
*gbo
;
419 /* TTM may pass BOs that are not GEM VRAM BOs. */
420 if (!drm_is_gem_vram(bo
))
423 gbo
= drm_gem_vram_of_bo(bo
);
424 drm_gem_vram_placement(gbo
, TTM_PL_FLAG_SYSTEM
);
425 *pl
= gbo
->placement
;
427 EXPORT_SYMBOL(drm_gem_vram_bo_driver_evict_flags
);
430 * drm_gem_vram_bo_driver_verify_access() - \
431 Implements &struct ttm_bo_driver.verify_access
432 * @bo: TTM buffer object. Refers to &struct drm_gem_vram_object.bo
433 * @filp: File pointer.
437 * a negative errno code otherwise.
439 int drm_gem_vram_bo_driver_verify_access(struct ttm_buffer_object
*bo
,
442 struct drm_gem_vram_object
*gbo
= drm_gem_vram_of_bo(bo
);
444 return drm_vma_node_verify_access(&gbo
->gem
.vma_node
,
447 EXPORT_SYMBOL(drm_gem_vram_bo_driver_verify_access
);
450 * drm_gem_vram_mm_funcs - Functions for &struct drm_vram_mm
452 * Most users of @struct drm_gem_vram_object will also use
453 * @struct drm_vram_mm. This instance of &struct drm_vram_mm_funcs
454 * can be used to connect both.
456 const struct drm_vram_mm_funcs drm_gem_vram_mm_funcs
= {
457 .evict_flags
= drm_gem_vram_bo_driver_evict_flags
,
458 .verify_access
= drm_gem_vram_bo_driver_verify_access
460 EXPORT_SYMBOL(drm_gem_vram_mm_funcs
);
463 * Helpers for struct drm_driver
467 * drm_gem_vram_driver_gem_free_object_unlocked() - \
468 Implements &struct drm_driver.gem_free_object_unlocked
469 * @gem: GEM object. Refers to &struct drm_gem_vram_object.gem
471 void drm_gem_vram_driver_gem_free_object_unlocked(struct drm_gem_object
*gem
)
473 struct drm_gem_vram_object
*gbo
= drm_gem_vram_of_gem(gem
);
475 drm_gem_vram_put(gbo
);
477 EXPORT_SYMBOL(drm_gem_vram_driver_gem_free_object_unlocked
);
480 * drm_gem_vram_driver_create_dumb() - \
481 Implements &struct drm_driver.dumb_create
482 * @file: the DRM file
483 * @dev: the DRM device
484 * @args: the arguments as provided to \
485 &struct drm_driver.dumb_create
487 * This function requires the driver to use @drm_device.vram_mm for its
488 * instance of VRAM MM.
492 * a negative error code otherwise.
494 int drm_gem_vram_driver_dumb_create(struct drm_file
*file
,
495 struct drm_device
*dev
,
496 struct drm_mode_create_dumb
*args
)
498 if (WARN_ONCE(!dev
->vram_mm
, "VRAM MM not initialized"))
501 return drm_gem_vram_fill_create_dumb(file
, dev
, &dev
->vram_mm
->bdev
, 0,
504 EXPORT_SYMBOL(drm_gem_vram_driver_dumb_create
);
507 * drm_gem_vram_driver_dumb_mmap_offset() - \
508 Implements &struct drm_driver.dumb_mmap_offset
509 * @file: DRM file pointer.
511 * @handle: GEM handle
512 * @offset: Returns the mapping's memory offset on success
516 * a negative errno code otherwise.
518 int drm_gem_vram_driver_dumb_mmap_offset(struct drm_file
*file
,
519 struct drm_device
*dev
,
520 uint32_t handle
, uint64_t *offset
)
522 struct drm_gem_object
*gem
;
523 struct drm_gem_vram_object
*gbo
;
525 gem
= drm_gem_object_lookup(file
, handle
);
529 gbo
= drm_gem_vram_of_gem(gem
);
530 *offset
= drm_gem_vram_mmap_offset(gbo
);
532 drm_gem_object_put_unlocked(gem
);
536 EXPORT_SYMBOL(drm_gem_vram_driver_dumb_mmap_offset
);
539 * PRIME helpers for struct drm_driver
543 * drm_gem_vram_driver_gem_prime_pin() - \
544 Implements &struct drm_driver.gem_prime_pin
545 * @gem: The GEM object to pin
549 * a negative errno code otherwise.
551 int drm_gem_vram_driver_gem_prime_pin(struct drm_gem_object
*gem
)
553 struct drm_gem_vram_object
*gbo
= drm_gem_vram_of_gem(gem
);
555 /* Fbdev console emulation is the use case of these PRIME
556 * helpers. This may involve updating a hardware buffer from
557 * a shadow FB. We pin the buffer to it's current location
558 * (either video RAM or system memory) to prevent it from
559 * being relocated during the update operation. If you require
560 * the buffer to be pinned to VRAM, implement a callback that
561 * sets the flags accordingly.
563 return drm_gem_vram_pin(gbo
, 0);
565 EXPORT_SYMBOL(drm_gem_vram_driver_gem_prime_pin
);
568 * drm_gem_vram_driver_gem_prime_unpin() - \
569 Implements &struct drm_driver.gem_prime_unpin
570 * @gem: The GEM object to unpin
572 void drm_gem_vram_driver_gem_prime_unpin(struct drm_gem_object
*gem
)
574 struct drm_gem_vram_object
*gbo
= drm_gem_vram_of_gem(gem
);
576 drm_gem_vram_unpin(gbo
);
578 EXPORT_SYMBOL(drm_gem_vram_driver_gem_prime_unpin
);
581 * drm_gem_vram_driver_gem_prime_vmap() - \
582 Implements &struct drm_driver.gem_prime_vmap
583 * @gem: The GEM object to map
586 * The buffers virtual address on success, or
589 void *drm_gem_vram_driver_gem_prime_vmap(struct drm_gem_object
*gem
)
591 struct drm_gem_vram_object
*gbo
= drm_gem_vram_of_gem(gem
);
595 ret
= drm_gem_vram_pin(gbo
, 0);
598 base
= drm_gem_vram_kmap(gbo
, true, NULL
);
600 drm_gem_vram_unpin(gbo
);
605 EXPORT_SYMBOL(drm_gem_vram_driver_gem_prime_vmap
);
608 * drm_gem_vram_driver_gem_prime_vunmap() - \
609 Implements &struct drm_driver.gem_prime_vunmap
610 * @gem: The GEM object to unmap
611 * @vaddr: The mapping's base address
613 void drm_gem_vram_driver_gem_prime_vunmap(struct drm_gem_object
*gem
,
616 struct drm_gem_vram_object
*gbo
= drm_gem_vram_of_gem(gem
);
618 drm_gem_vram_kunmap(gbo
);
619 drm_gem_vram_unpin(gbo
);
621 EXPORT_SYMBOL(drm_gem_vram_driver_gem_prime_vunmap
);
624 * drm_gem_vram_driver_gem_prime_mmap() - \
625 Implements &struct drm_driver.gem_prime_mmap
626 * @gem: The GEM object to map
627 * @vma: The VMA describing the mapping
631 * a negative errno code otherwise.
633 int drm_gem_vram_driver_gem_prime_mmap(struct drm_gem_object
*gem
,
634 struct vm_area_struct
*vma
)
636 struct drm_gem_vram_object
*gbo
= drm_gem_vram_of_gem(gem
);
638 gbo
->gem
.vma_node
.vm_node
.start
= gbo
->bo
.vma_node
.vm_node
.start
;
639 return drm_gem_prime_mmap(gem
, vma
);
641 EXPORT_SYMBOL(drm_gem_vram_driver_gem_prime_mmap
);