xref: /kernel/linux/linux-5.10/drivers/gpu/drm/tegra/gem.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * NVIDIA Tegra DRM GEM helper functions
4 *
5 * Copyright (C) 2012 Sascha Hauer, Pengutronix
6 * Copyright (C) 2013-2015 NVIDIA CORPORATION, All rights reserved.
7 *
8 * Based on the GEM/CMA helpers
9 *
10 * Copyright (c) 2011 Samsung Electronics Co., Ltd.
11 */
12
13#include <linux/dma-buf.h>
14#include <linux/iommu.h>
15
16#include <drm/drm_drv.h>
17#include <drm/drm_prime.h>
18#include <drm/tegra_drm.h>
19
20#include "drm.h"
21#include "gem.h"
22
23static void tegra_bo_put(struct host1x_bo *bo)
24{
25	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
26
27	drm_gem_object_put(&obj->gem);
28}
29
30/* XXX move this into lib/scatterlist.c? */
31static int sg_alloc_table_from_sg(struct sg_table *sgt, struct scatterlist *sg,
32				  unsigned int nents, gfp_t gfp_mask)
33{
34	struct scatterlist *dst;
35	unsigned int i;
36	int err;
37
38	err = sg_alloc_table(sgt, nents, gfp_mask);
39	if (err < 0)
40		return err;
41
42	dst = sgt->sgl;
43
44	for (i = 0; i < nents; i++) {
45		sg_set_page(dst, sg_page(sg), sg->length, 0);
46		dst = sg_next(dst);
47		sg = sg_next(sg);
48	}
49
50	return 0;
51}
52
53static struct sg_table *tegra_bo_pin(struct device *dev, struct host1x_bo *bo,
54				     dma_addr_t *phys)
55{
56	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
57	struct sg_table *sgt;
58	int err;
59
60	/*
61	 * If we've manually mapped the buffer object through the IOMMU, make
62	 * sure to return the IOVA address of our mapping.
63	 *
64	 * Similarly, for buffers that have been allocated by the DMA API the
65	 * physical address can be used for devices that are not attached to
66	 * an IOMMU. For these devices, callers must pass a valid pointer via
67	 * the @phys argument.
68	 *
69	 * Imported buffers were also already mapped at import time, so the
70	 * existing mapping can be reused.
71	 */
72	if (phys) {
73		*phys = obj->iova;
74		return NULL;
75	}
76
77	/*
78	 * If we don't have a mapping for this buffer yet, return an SG table
79	 * so that host1x can do the mapping for us via the DMA API.
80	 */
81	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
82	if (!sgt)
83		return ERR_PTR(-ENOMEM);
84
85	if (obj->pages) {
86		/*
87		 * If the buffer object was allocated from the explicit IOMMU
88		 * API code paths, construct an SG table from the pages.
89		 */
90		err = sg_alloc_table_from_pages(sgt, obj->pages, obj->num_pages,
91						0, obj->gem.size, GFP_KERNEL);
92		if (err < 0)
93			goto free;
94	} else if (obj->sgt) {
95		/*
96		 * If the buffer object already has an SG table but no pages
97		 * were allocated for it, it means the buffer was imported and
98		 * the SG table needs to be copied to avoid overwriting any
99		 * other potential users of the original SG table.
100		 */
101		err = sg_alloc_table_from_sg(sgt, obj->sgt->sgl,
102					     obj->sgt->orig_nents, GFP_KERNEL);
103		if (err < 0)
104			goto free;
105	} else {
106		/*
107		 * If the buffer object had no pages allocated and if it was
108		 * not imported, it had to be allocated with the DMA API, so
109		 * the DMA API helper can be used.
110		 */
111		err = dma_get_sgtable(dev, sgt, obj->vaddr, obj->iova,
112				      obj->gem.size);
113		if (err < 0)
114			goto free;
115	}
116
117	return sgt;
118
119free:
120	kfree(sgt);
121	return ERR_PTR(err);
122}
123
124static void tegra_bo_unpin(struct device *dev, struct sg_table *sgt)
125{
126	if (sgt) {
127		sg_free_table(sgt);
128		kfree(sgt);
129	}
130}
131
132static void *tegra_bo_mmap(struct host1x_bo *bo)
133{
134	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
135
136	if (obj->vaddr)
137		return obj->vaddr;
138	else if (obj->gem.import_attach)
139		return dma_buf_vmap(obj->gem.import_attach->dmabuf);
140	else
141		return vmap(obj->pages, obj->num_pages, VM_MAP,
142			    pgprot_writecombine(PAGE_KERNEL));
143}
144
145static void tegra_bo_munmap(struct host1x_bo *bo, void *addr)
146{
147	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
148
149	if (obj->vaddr)
150		return;
151	else if (obj->gem.import_attach)
152		dma_buf_vunmap(obj->gem.import_attach->dmabuf, addr);
153	else
154		vunmap(addr);
155}
156
157static struct host1x_bo *tegra_bo_get(struct host1x_bo *bo)
158{
159	struct tegra_bo *obj = host1x_to_tegra_bo(bo);
160
161	drm_gem_object_get(&obj->gem);
162
163	return bo;
164}
165
166static const struct host1x_bo_ops tegra_bo_ops = {
167	.get = tegra_bo_get,
168	.put = tegra_bo_put,
169	.pin = tegra_bo_pin,
170	.unpin = tegra_bo_unpin,
171	.mmap = tegra_bo_mmap,
172	.munmap = tegra_bo_munmap,
173};
174
175static int tegra_bo_iommu_map(struct tegra_drm *tegra, struct tegra_bo *bo)
176{
177	int prot = IOMMU_READ | IOMMU_WRITE;
178	int err;
179
180	if (bo->mm)
181		return -EBUSY;
182
183	bo->mm = kzalloc(sizeof(*bo->mm), GFP_KERNEL);
184	if (!bo->mm)
185		return -ENOMEM;
186
187	mutex_lock(&tegra->mm_lock);
188
189	err = drm_mm_insert_node_generic(&tegra->mm,
190					 bo->mm, bo->gem.size, PAGE_SIZE, 0, 0);
191	if (err < 0) {
192		dev_err(tegra->drm->dev, "out of I/O virtual memory: %d\n",
193			err);
194		goto unlock;
195	}
196
197	bo->iova = bo->mm->start;
198
199	bo->size = iommu_map_sgtable(tegra->domain, bo->iova, bo->sgt, prot);
200	if (!bo->size) {
201		dev_err(tegra->drm->dev, "failed to map buffer\n");
202		err = -ENOMEM;
203		goto remove;
204	}
205
206	mutex_unlock(&tegra->mm_lock);
207
208	return 0;
209
210remove:
211	drm_mm_remove_node(bo->mm);
212unlock:
213	mutex_unlock(&tegra->mm_lock);
214	kfree(bo->mm);
215	return err;
216}
217
218static int tegra_bo_iommu_unmap(struct tegra_drm *tegra, struct tegra_bo *bo)
219{
220	if (!bo->mm)
221		return 0;
222
223	mutex_lock(&tegra->mm_lock);
224	iommu_unmap(tegra->domain, bo->iova, bo->size);
225	drm_mm_remove_node(bo->mm);
226	mutex_unlock(&tegra->mm_lock);
227
228	kfree(bo->mm);
229
230	return 0;
231}
232
233static struct tegra_bo *tegra_bo_alloc_object(struct drm_device *drm,
234					      size_t size)
235{
236	struct tegra_bo *bo;
237	int err;
238
239	bo = kzalloc(sizeof(*bo), GFP_KERNEL);
240	if (!bo)
241		return ERR_PTR(-ENOMEM);
242
243	host1x_bo_init(&bo->base, &tegra_bo_ops);
244	size = round_up(size, PAGE_SIZE);
245
246	err = drm_gem_object_init(drm, &bo->gem, size);
247	if (err < 0)
248		goto free;
249
250	err = drm_gem_create_mmap_offset(&bo->gem);
251	if (err < 0)
252		goto release;
253
254	return bo;
255
256release:
257	drm_gem_object_release(&bo->gem);
258free:
259	kfree(bo);
260	return ERR_PTR(err);
261}
262
263static void tegra_bo_free(struct drm_device *drm, struct tegra_bo *bo)
264{
265	if (bo->pages) {
266		dma_unmap_sgtable(drm->dev, bo->sgt, DMA_FROM_DEVICE, 0);
267		drm_gem_put_pages(&bo->gem, bo->pages, true, true);
268		sg_free_table(bo->sgt);
269		kfree(bo->sgt);
270	} else if (bo->vaddr) {
271		dma_free_wc(drm->dev, bo->gem.size, bo->vaddr, bo->iova);
272	}
273}
274
275static int tegra_bo_get_pages(struct drm_device *drm, struct tegra_bo *bo)
276{
277	int err;
278
279	bo->pages = drm_gem_get_pages(&bo->gem);
280	if (IS_ERR(bo->pages))
281		return PTR_ERR(bo->pages);
282
283	bo->num_pages = bo->gem.size >> PAGE_SHIFT;
284
285	bo->sgt = drm_prime_pages_to_sg(bo->gem.dev, bo->pages, bo->num_pages);
286	if (IS_ERR(bo->sgt)) {
287		err = PTR_ERR(bo->sgt);
288		goto put_pages;
289	}
290
291	err = dma_map_sgtable(drm->dev, bo->sgt, DMA_FROM_DEVICE, 0);
292	if (err)
293		goto free_sgt;
294
295	return 0;
296
297free_sgt:
298	sg_free_table(bo->sgt);
299	kfree(bo->sgt);
300put_pages:
301	drm_gem_put_pages(&bo->gem, bo->pages, false, false);
302	return err;
303}
304
305static int tegra_bo_alloc(struct drm_device *drm, struct tegra_bo *bo)
306{
307	struct tegra_drm *tegra = drm->dev_private;
308	int err;
309
310	if (tegra->domain) {
311		err = tegra_bo_get_pages(drm, bo);
312		if (err < 0)
313			return err;
314
315		err = tegra_bo_iommu_map(tegra, bo);
316		if (err < 0) {
317			tegra_bo_free(drm, bo);
318			return err;
319		}
320	} else {
321		size_t size = bo->gem.size;
322
323		bo->vaddr = dma_alloc_wc(drm->dev, size, &bo->iova,
324					 GFP_KERNEL | __GFP_NOWARN);
325		if (!bo->vaddr) {
326			dev_err(drm->dev,
327				"failed to allocate buffer of size %zu\n",
328				size);
329			return -ENOMEM;
330		}
331	}
332
333	return 0;
334}
335
336struct tegra_bo *tegra_bo_create(struct drm_device *drm, size_t size,
337				 unsigned long flags)
338{
339	struct tegra_bo *bo;
340	int err;
341
342	bo = tegra_bo_alloc_object(drm, size);
343	if (IS_ERR(bo))
344		return bo;
345
346	err = tegra_bo_alloc(drm, bo);
347	if (err < 0)
348		goto release;
349
350	if (flags & DRM_TEGRA_GEM_CREATE_TILED)
351		bo->tiling.mode = TEGRA_BO_TILING_MODE_TILED;
352
353	if (flags & DRM_TEGRA_GEM_CREATE_BOTTOM_UP)
354		bo->flags |= TEGRA_BO_BOTTOM_UP;
355
356	return bo;
357
358release:
359	drm_gem_object_release(&bo->gem);
360	kfree(bo);
361	return ERR_PTR(err);
362}
363
364struct tegra_bo *tegra_bo_create_with_handle(struct drm_file *file,
365					     struct drm_device *drm,
366					     size_t size,
367					     unsigned long flags,
368					     u32 *handle)
369{
370	struct tegra_bo *bo;
371	int err;
372
373	bo = tegra_bo_create(drm, size, flags);
374	if (IS_ERR(bo))
375		return bo;
376
377	err = drm_gem_handle_create(file, &bo->gem, handle);
378	if (err) {
379		tegra_bo_free_object(&bo->gem);
380		return ERR_PTR(err);
381	}
382
383	drm_gem_object_put(&bo->gem);
384
385	return bo;
386}
387
388static struct tegra_bo *tegra_bo_import(struct drm_device *drm,
389					struct dma_buf *buf)
390{
391	struct tegra_drm *tegra = drm->dev_private;
392	struct dma_buf_attachment *attach;
393	struct tegra_bo *bo;
394	int err;
395
396	bo = tegra_bo_alloc_object(drm, buf->size);
397	if (IS_ERR(bo))
398		return bo;
399
400	attach = dma_buf_attach(buf, drm->dev);
401	if (IS_ERR(attach)) {
402		err = PTR_ERR(attach);
403		goto free;
404	}
405
406	get_dma_buf(buf);
407
408	bo->sgt = dma_buf_map_attachment(attach, DMA_TO_DEVICE);
409	if (IS_ERR(bo->sgt)) {
410		err = PTR_ERR(bo->sgt);
411		goto detach;
412	}
413
414	if (tegra->domain) {
415		err = tegra_bo_iommu_map(tegra, bo);
416		if (err < 0)
417			goto detach;
418	}
419
420	bo->gem.import_attach = attach;
421
422	return bo;
423
424detach:
425	if (!IS_ERR_OR_NULL(bo->sgt))
426		dma_buf_unmap_attachment(attach, bo->sgt, DMA_TO_DEVICE);
427
428	dma_buf_detach(buf, attach);
429	dma_buf_put(buf);
430free:
431	drm_gem_object_release(&bo->gem);
432	kfree(bo);
433	return ERR_PTR(err);
434}
435
436void tegra_bo_free_object(struct drm_gem_object *gem)
437{
438	struct tegra_drm *tegra = gem->dev->dev_private;
439	struct tegra_bo *bo = to_tegra_bo(gem);
440
441	if (tegra->domain)
442		tegra_bo_iommu_unmap(tegra, bo);
443
444	if (gem->import_attach) {
445		dma_buf_unmap_attachment(gem->import_attach, bo->sgt,
446					 DMA_TO_DEVICE);
447		drm_prime_gem_destroy(gem, NULL);
448	} else {
449		tegra_bo_free(gem->dev, bo);
450	}
451
452	drm_gem_object_release(gem);
453	kfree(bo);
454}
455
456int tegra_bo_dumb_create(struct drm_file *file, struct drm_device *drm,
457			 struct drm_mode_create_dumb *args)
458{
459	unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
460	struct tegra_drm *tegra = drm->dev_private;
461	struct tegra_bo *bo;
462
463	args->pitch = round_up(min_pitch, tegra->pitch_align);
464	args->size = args->pitch * args->height;
465
466	bo = tegra_bo_create_with_handle(file, drm, args->size, 0,
467					 &args->handle);
468	if (IS_ERR(bo))
469		return PTR_ERR(bo);
470
471	return 0;
472}
473
474static vm_fault_t tegra_bo_fault(struct vm_fault *vmf)
475{
476	struct vm_area_struct *vma = vmf->vma;
477	struct drm_gem_object *gem = vma->vm_private_data;
478	struct tegra_bo *bo = to_tegra_bo(gem);
479	struct page *page;
480	pgoff_t offset;
481
482	if (!bo->pages)
483		return VM_FAULT_SIGBUS;
484
485	offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
486	page = bo->pages[offset];
487
488	return vmf_insert_page(vma, vmf->address, page);
489}
490
491const struct vm_operations_struct tegra_bo_vm_ops = {
492	.fault = tegra_bo_fault,
493	.open = drm_gem_vm_open,
494	.close = drm_gem_vm_close,
495};
496
497int __tegra_gem_mmap(struct drm_gem_object *gem, struct vm_area_struct *vma)
498{
499	struct tegra_bo *bo = to_tegra_bo(gem);
500
501	if (!bo->pages) {
502		unsigned long vm_pgoff = vma->vm_pgoff;
503		int err;
504
505		/*
506		 * Clear the VM_PFNMAP flag that was set by drm_gem_mmap(),
507		 * and set the vm_pgoff (used as a fake buffer offset by DRM)
508		 * to 0 as we want to map the whole buffer.
509		 */
510		vma->vm_flags &= ~VM_PFNMAP;
511		vma->vm_pgoff = 0;
512
513		err = dma_mmap_wc(gem->dev->dev, vma, bo->vaddr, bo->iova,
514				  gem->size);
515		if (err < 0) {
516			drm_gem_vm_close(vma);
517			return err;
518		}
519
520		vma->vm_pgoff = vm_pgoff;
521	} else {
522		pgprot_t prot = vm_get_page_prot(vma->vm_flags);
523
524		vma->vm_flags |= VM_MIXEDMAP;
525		vma->vm_flags &= ~VM_PFNMAP;
526
527		vma->vm_page_prot = pgprot_writecombine(prot);
528	}
529
530	return 0;
531}
532
533int tegra_drm_mmap(struct file *file, struct vm_area_struct *vma)
534{
535	struct drm_gem_object *gem;
536	int err;
537
538	err = drm_gem_mmap(file, vma);
539	if (err < 0)
540		return err;
541
542	gem = vma->vm_private_data;
543
544	return __tegra_gem_mmap(gem, vma);
545}
546
547static struct sg_table *
548tegra_gem_prime_map_dma_buf(struct dma_buf_attachment *attach,
549			    enum dma_data_direction dir)
550{
551	struct drm_gem_object *gem = attach->dmabuf->priv;
552	struct tegra_bo *bo = to_tegra_bo(gem);
553	struct sg_table *sgt;
554
555	sgt = kmalloc(sizeof(*sgt), GFP_KERNEL);
556	if (!sgt)
557		return NULL;
558
559	if (bo->pages) {
560		if (sg_alloc_table_from_pages(sgt, bo->pages, bo->num_pages,
561					      0, gem->size, GFP_KERNEL) < 0)
562			goto free;
563	} else {
564		if (dma_get_sgtable(attach->dev, sgt, bo->vaddr, bo->iova,
565				    gem->size) < 0)
566			goto free;
567	}
568
569	if (dma_map_sgtable(attach->dev, sgt, dir, 0))
570		goto free;
571
572	return sgt;
573
574free:
575	sg_free_table(sgt);
576	kfree(sgt);
577	return NULL;
578}
579
580static void tegra_gem_prime_unmap_dma_buf(struct dma_buf_attachment *attach,
581					  struct sg_table *sgt,
582					  enum dma_data_direction dir)
583{
584	struct drm_gem_object *gem = attach->dmabuf->priv;
585	struct tegra_bo *bo = to_tegra_bo(gem);
586
587	if (bo->pages)
588		dma_unmap_sgtable(attach->dev, sgt, dir, 0);
589
590	sg_free_table(sgt);
591	kfree(sgt);
592}
593
594static void tegra_gem_prime_release(struct dma_buf *buf)
595{
596	drm_gem_dmabuf_release(buf);
597}
598
599static int tegra_gem_prime_begin_cpu_access(struct dma_buf *buf,
600					    enum dma_data_direction direction)
601{
602	struct drm_gem_object *gem = buf->priv;
603	struct tegra_bo *bo = to_tegra_bo(gem);
604	struct drm_device *drm = gem->dev;
605
606	if (bo->pages)
607		dma_sync_sgtable_for_cpu(drm->dev, bo->sgt, DMA_FROM_DEVICE);
608
609	return 0;
610}
611
612static int tegra_gem_prime_end_cpu_access(struct dma_buf *buf,
613					  enum dma_data_direction direction)
614{
615	struct drm_gem_object *gem = buf->priv;
616	struct tegra_bo *bo = to_tegra_bo(gem);
617	struct drm_device *drm = gem->dev;
618
619	if (bo->pages)
620		dma_sync_sgtable_for_device(drm->dev, bo->sgt, DMA_TO_DEVICE);
621
622	return 0;
623}
624
625static int tegra_gem_prime_mmap(struct dma_buf *buf, struct vm_area_struct *vma)
626{
627	struct drm_gem_object *gem = buf->priv;
628	int err;
629
630	err = drm_gem_mmap_obj(gem, gem->size, vma);
631	if (err < 0)
632		return err;
633
634	return __tegra_gem_mmap(gem, vma);
635}
636
637static void *tegra_gem_prime_vmap(struct dma_buf *buf)
638{
639	struct drm_gem_object *gem = buf->priv;
640	struct tegra_bo *bo = to_tegra_bo(gem);
641
642	return bo->vaddr;
643}
644
645static void tegra_gem_prime_vunmap(struct dma_buf *buf, void *vaddr)
646{
647}
648
649static const struct dma_buf_ops tegra_gem_prime_dmabuf_ops = {
650	.map_dma_buf = tegra_gem_prime_map_dma_buf,
651	.unmap_dma_buf = tegra_gem_prime_unmap_dma_buf,
652	.release = tegra_gem_prime_release,
653	.begin_cpu_access = tegra_gem_prime_begin_cpu_access,
654	.end_cpu_access = tegra_gem_prime_end_cpu_access,
655	.mmap = tegra_gem_prime_mmap,
656	.vmap = tegra_gem_prime_vmap,
657	.vunmap = tegra_gem_prime_vunmap,
658};
659
660struct dma_buf *tegra_gem_prime_export(struct drm_gem_object *gem,
661				       int flags)
662{
663	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
664
665	exp_info.exp_name = KBUILD_MODNAME;
666	exp_info.owner = gem->dev->driver->fops->owner;
667	exp_info.ops = &tegra_gem_prime_dmabuf_ops;
668	exp_info.size = gem->size;
669	exp_info.flags = flags;
670	exp_info.priv = gem;
671
672	return drm_gem_dmabuf_export(gem->dev, &exp_info);
673}
674
675struct drm_gem_object *tegra_gem_prime_import(struct drm_device *drm,
676					      struct dma_buf *buf)
677{
678	struct tegra_bo *bo;
679
680	if (buf->ops == &tegra_gem_prime_dmabuf_ops) {
681		struct drm_gem_object *gem = buf->priv;
682
683		if (gem->dev == drm) {
684			drm_gem_object_get(gem);
685			return gem;
686		}
687	}
688
689	bo = tegra_bo_import(drm, buf);
690	if (IS_ERR(bo))
691		return ERR_CAST(bo);
692
693	return &bo->gem;
694}
695