xref: /linux/drivers/gpu/drm/rockchip/rockchip_drm_gem.c (revision face6a3615a649456eb4549f6d474221d877d604) 
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) Rockchip Electronics Co., Ltd.
4  * Author:Mark Yao <mark.yao@rock-chips.com>
5  */
6 
7 #include <linux/dma-buf.h>
8 #include <linux/iommu.h>
9 #include <linux/vmalloc.h>
10 
11 #include <drm/drm.h>
12 #include <drm/drm_dumb_buffers.h>
13 #include <drm/drm_fb_helper.h>
14 #include <drm/drm_gem.h>
15 #include <drm/drm_gem_dma_helper.h>
16 #include <drm/drm_prime.h>
17 #include <drm/drm_vma_manager.h>
18 
19 #include "rockchip_drm_drv.h"
20 #include "rockchip_drm_gem.h"
21 
22 static int rockchip_gem_iommu_map(struct rockchip_gem_object *rk_obj)
23 {
24 	struct drm_device *drm = rk_obj->base.dev;
25 	struct rockchip_drm_private *private = drm->dev_private;
26 	int prot = IOMMU_READ | IOMMU_WRITE;
27 	ssize_t ret;
28 
29 	mutex_lock(&private->mm_lock);
30 	ret = drm_mm_insert_node_generic(&private->mm, &rk_obj->mm,
31 					 rk_obj->base.size, PAGE_SIZE,
32 					 0, 0);
33 	mutex_unlock(&private->mm_lock);
34 
35 	if (ret < 0) {
36 		DRM_ERROR("out of I/O virtual memory: %zd\n", ret);
37 		return ret;
38 	}
39 
40 	rk_obj->dma_addr = rk_obj->mm.start;
41 
42 	ret = iommu_map_sgtable(private->domain, rk_obj->dma_addr, rk_obj->sgt,
43 				prot);
44 	if (ret < (ssize_t)rk_obj->base.size) {
45 		DRM_ERROR("failed to map buffer: size=%zd request_size=%zd\n",
46 			  ret, rk_obj->base.size);
47 		ret = -ENOMEM;
48 		goto err_remove_node;
49 	}
50 
51 	rk_obj->size = ret;
52 
53 	return 0;
54 
55 err_remove_node:
56 	mutex_lock(&private->mm_lock);
57 	drm_mm_remove_node(&rk_obj->mm);
58 	mutex_unlock(&private->mm_lock);
59 
60 	return ret;
61 }
62 
63 static int rockchip_gem_iommu_unmap(struct rockchip_gem_object *rk_obj)
64 {
65 	struct drm_device *drm = rk_obj->base.dev;
66 	struct rockchip_drm_private *private = drm->dev_private;
67 
68 	iommu_unmap(private->domain, rk_obj->dma_addr, rk_obj->size);
69 
70 	mutex_lock(&private->mm_lock);
71 
72 	drm_mm_remove_node(&rk_obj->mm);
73 
74 	mutex_unlock(&private->mm_lock);
75 
76 	return 0;
77 }
78 
79 static int rockchip_gem_get_pages(struct rockchip_gem_object *rk_obj)
80 {
81 	struct drm_device *drm = rk_obj->base.dev;
82 	int ret, i;
83 	struct scatterlist *s;
84 
85 	rk_obj->pages = drm_gem_get_pages(&rk_obj->base);
86 	if (IS_ERR(rk_obj->pages))
87 		return PTR_ERR(rk_obj->pages);
88 
89 	rk_obj->num_pages = rk_obj->base.size >> PAGE_SHIFT;
90 
91 	rk_obj->sgt = drm_prime_pages_to_sg(rk_obj->base.dev,
92 					    rk_obj->pages, rk_obj->num_pages);
93 	if (IS_ERR(rk_obj->sgt)) {
94 		ret = PTR_ERR(rk_obj->sgt);
95 		goto err_put_pages;
96 	}
97 
98 	/*
99 	 * Fake up the SG table so that dma_sync_sg_for_device() can be used
100 	 * to flush the pages associated with it.
101 	 *
102 	 * TODO: Replace this by drm_clflush_sg() once it can be implemented
103 	 * without relying on symbols that are not exported.
104 	 */
105 	for_each_sgtable_sg(rk_obj->sgt, s, i)
106 		sg_dma_address(s) = sg_phys(s);
107 
108 	dma_sync_sgtable_for_device(drm->dev, rk_obj->sgt, DMA_TO_DEVICE);
109 
110 	return 0;
111 
112 err_put_pages:
113 	drm_gem_put_pages(&rk_obj->base, rk_obj->pages, false, false);
114 	return ret;
115 }
116 
117 static void rockchip_gem_put_pages(struct rockchip_gem_object *rk_obj)
118 {
119 	sg_free_table(rk_obj->sgt);
120 	kfree(rk_obj->sgt);
121 	drm_gem_put_pages(&rk_obj->base, rk_obj->pages, true, true);
122 }
123 
124 static int rockchip_gem_alloc_iommu(struct rockchip_gem_object *rk_obj,
125 				    bool alloc_kmap)
126 {
127 	int ret;
128 
129 	ret = rockchip_gem_get_pages(rk_obj);
130 	if (ret < 0)
131 		return ret;
132 
133 	ret = rockchip_gem_iommu_map(rk_obj);
134 	if (ret < 0)
135 		goto err_free;
136 
137 	if (alloc_kmap) {
138 		rk_obj->kvaddr = vmap(rk_obj->pages, rk_obj->num_pages, VM_MAP,
139 				      pgprot_writecombine(PAGE_KERNEL));
140 		if (!rk_obj->kvaddr) {
141 			DRM_ERROR("failed to vmap() buffer\n");
142 			ret = -ENOMEM;
143 			goto err_unmap;
144 		}
145 	}
146 
147 	return 0;
148 
149 err_unmap:
150 	rockchip_gem_iommu_unmap(rk_obj);
151 err_free:
152 	rockchip_gem_put_pages(rk_obj);
153 
154 	return ret;
155 }
156 
157 static int rockchip_gem_alloc_dma(struct rockchip_gem_object *rk_obj,
158 				  bool alloc_kmap)
159 {
160 	struct drm_gem_object *obj = &rk_obj->base;
161 	struct drm_device *drm = obj->dev;
162 
163 	rk_obj->dma_attrs = DMA_ATTR_WRITE_COMBINE;
164 
165 	if (!alloc_kmap)
166 		rk_obj->dma_attrs |= DMA_ATTR_NO_KERNEL_MAPPING;
167 
168 	rk_obj->kvaddr = dma_alloc_attrs(drm->dev, obj->size,
169 					 &rk_obj->dma_addr, GFP_KERNEL,
170 					 rk_obj->dma_attrs);
171 	if (!rk_obj->kvaddr) {
172 		DRM_ERROR("failed to allocate %zu byte dma buffer", obj->size);
173 		return -ENOMEM;
174 	}
175 
176 	return 0;
177 }
178 
179 static int rockchip_gem_alloc_buf(struct rockchip_gem_object *rk_obj,
180 				  bool alloc_kmap)
181 {
182 	struct drm_gem_object *obj = &rk_obj->base;
183 	struct drm_device *drm = obj->dev;
184 	struct rockchip_drm_private *private = drm->dev_private;
185 
186 	if (private->domain)
187 		return rockchip_gem_alloc_iommu(rk_obj, alloc_kmap);
188 	else
189 		return rockchip_gem_alloc_dma(rk_obj, alloc_kmap);
190 }
191 
192 static void rockchip_gem_free_iommu(struct rockchip_gem_object *rk_obj)
193 {
194 	vunmap(rk_obj->kvaddr);
195 	rockchip_gem_iommu_unmap(rk_obj);
196 	rockchip_gem_put_pages(rk_obj);
197 }
198 
199 static void rockchip_gem_free_dma(struct rockchip_gem_object *rk_obj)
200 {
201 	struct drm_gem_object *obj = &rk_obj->base;
202 	struct drm_device *drm = obj->dev;
203 
204 	dma_free_attrs(drm->dev, obj->size, rk_obj->kvaddr, rk_obj->dma_addr,
205 		       rk_obj->dma_attrs);
206 }
207 
208 static void rockchip_gem_free_buf(struct rockchip_gem_object *rk_obj)
209 {
210 	if (rk_obj->pages)
211 		rockchip_gem_free_iommu(rk_obj);
212 	else
213 		rockchip_gem_free_dma(rk_obj);
214 }
215 
216 static int rockchip_drm_gem_object_mmap_iommu(struct drm_gem_object *obj,
217 					      struct vm_area_struct *vma)
218 {
219 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
220 	unsigned int count = obj->size >> PAGE_SHIFT;
221 	unsigned long user_count = vma_pages(vma);
222 
223 	if (user_count == 0)
224 		return -ENXIO;
225 
226 	return vm_map_pages(vma, rk_obj->pages, count);
227 }
228 
229 static int rockchip_drm_gem_object_mmap_dma(struct drm_gem_object *obj,
230 					    struct vm_area_struct *vma)
231 {
232 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
233 	struct drm_device *drm = obj->dev;
234 
235 	return dma_mmap_attrs(drm->dev, vma, rk_obj->kvaddr, rk_obj->dma_addr,
236 			      obj->size, rk_obj->dma_attrs);
237 }
238 
239 static int rockchip_drm_gem_object_mmap(struct drm_gem_object *obj,
240 					struct vm_area_struct *vma)
241 {
242 	int ret;
243 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
244 
245 	/*
246 	 * Set vm_pgoff (used as a fake buffer offset by DRM) to 0 and map the
247 	 * whole buffer from the start.
248 	 */
249 	vma->vm_pgoff = 0;
250 
251 	/*
252 	 * We allocated a struct page table for rk_obj, so clear
253 	 * VM_PFNMAP flag that was set by drm_gem_mmap_obj()/drm_gem_mmap().
254 	 */
255 	vm_flags_mod(vma, VM_IO | VM_DONTEXPAND | VM_DONTDUMP, VM_PFNMAP);
256 
257 	vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
258 	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
259 
260 	if (rk_obj->pages)
261 		ret = rockchip_drm_gem_object_mmap_iommu(obj, vma);
262 	else
263 		ret = rockchip_drm_gem_object_mmap_dma(obj, vma);
264 
265 	return ret;
266 }
267 
268 static void rockchip_gem_release_object(struct rockchip_gem_object *rk_obj)
269 {
270 	drm_gem_object_release(&rk_obj->base);
271 	kfree(rk_obj);
272 }
273 
274 static const struct drm_gem_object_funcs rockchip_gem_object_funcs = {
275 	.free = rockchip_gem_free_object,
276 	.get_sg_table = rockchip_gem_prime_get_sg_table,
277 	.vmap = rockchip_gem_prime_vmap,
278 	.vunmap	= rockchip_gem_prime_vunmap,
279 	.mmap = rockchip_drm_gem_object_mmap,
280 	.vm_ops = &drm_gem_dma_vm_ops,
281 };
282 
283 static struct rockchip_gem_object *
284 	rockchip_gem_alloc_object(struct drm_device *drm, unsigned int size)
285 {
286 	struct rockchip_gem_object *rk_obj;
287 	struct drm_gem_object *obj;
288 
289 	size = round_up(size, PAGE_SIZE);
290 
291 	rk_obj = kzalloc(sizeof(*rk_obj), GFP_KERNEL);
292 	if (!rk_obj)
293 		return ERR_PTR(-ENOMEM);
294 
295 	obj = &rk_obj->base;
296 
297 	obj->funcs = &rockchip_gem_object_funcs;
298 
299 	drm_gem_object_init(drm, obj, size);
300 
301 	return rk_obj;
302 }
303 
304 struct rockchip_gem_object *
305 rockchip_gem_create_object(struct drm_device *drm, unsigned int size,
306 			   bool alloc_kmap)
307 {
308 	struct rockchip_gem_object *rk_obj;
309 	int ret;
310 
311 	rk_obj = rockchip_gem_alloc_object(drm, size);
312 	if (IS_ERR(rk_obj))
313 		return rk_obj;
314 
315 	ret = rockchip_gem_alloc_buf(rk_obj, alloc_kmap);
316 	if (ret)
317 		goto err_free_rk_obj;
318 
319 	return rk_obj;
320 
321 err_free_rk_obj:
322 	rockchip_gem_release_object(rk_obj);
323 	return ERR_PTR(ret);
324 }
325 
326 /*
327  * rockchip_gem_free_object - (struct drm_gem_object_funcs)->free
328  * callback function
329  */
330 void rockchip_gem_free_object(struct drm_gem_object *obj)
331 {
332 	struct drm_device *drm = obj->dev;
333 	struct rockchip_drm_private *private = drm->dev_private;
334 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
335 
336 	if (obj->import_attach) {
337 		if (private->domain) {
338 			rockchip_gem_iommu_unmap(rk_obj);
339 		} else {
340 			dma_unmap_sgtable(drm->dev, rk_obj->sgt,
341 					  DMA_BIDIRECTIONAL, 0);
342 		}
343 		drm_prime_gem_destroy(obj, rk_obj->sgt);
344 	} else {
345 		rockchip_gem_free_buf(rk_obj);
346 	}
347 
348 	rockchip_gem_release_object(rk_obj);
349 }
350 
351 /*
352  * rockchip_gem_create_with_handle - allocate an object with the given
353  * size and create a gem handle on it
354  *
355  * returns a struct rockchip_gem_object* on success or ERR_PTR values
356  * on failure.
357  */
358 static struct rockchip_gem_object *
359 rockchip_gem_create_with_handle(struct drm_file *file_priv,
360 				struct drm_device *drm, unsigned int size,
361 				unsigned int *handle)
362 {
363 	struct rockchip_gem_object *rk_obj;
364 	struct drm_gem_object *obj;
365 	bool is_framebuffer;
366 	int ret;
367 
368 	is_framebuffer = drm->fb_helper && file_priv == drm->fb_helper->client.file;
369 
370 	rk_obj = rockchip_gem_create_object(drm, size, is_framebuffer);
371 	if (IS_ERR(rk_obj))
372 		return ERR_CAST(rk_obj);
373 
374 	obj = &rk_obj->base;
375 
376 	/*
377 	 * allocate a id of idr table where the obj is registered
378 	 * and handle has the id what user can see.
379 	 */
380 	ret = drm_gem_handle_create(file_priv, obj, handle);
381 	if (ret)
382 		goto err_handle_create;
383 
384 	/* drop reference from allocate - handle holds it now. */
385 	drm_gem_object_put(obj);
386 
387 	return rk_obj;
388 
389 err_handle_create:
390 	rockchip_gem_free_object(obj);
391 
392 	return ERR_PTR(ret);
393 }
394 
395 /*
396  * rockchip_gem_dumb_create - (struct drm_driver)->dumb_create callback
397  * function
398  *
399  * This aligns the pitch and size arguments to the minimum required. wrap
400  * this into your own function if you need bigger alignment.
401  */
402 int rockchip_gem_dumb_create(struct drm_file *file_priv,
403 			     struct drm_device *dev,
404 			     struct drm_mode_create_dumb *args)
405 {
406 	struct rockchip_gem_object *rk_obj;
407 	int ret;
408 
409 	/* 64-byte alignment required by Mali */
410 	ret = drm_mode_size_dumb(dev, args, SZ_64, 0);
411 	if (ret)
412 		return ret;
413 
414 	rk_obj = rockchip_gem_create_with_handle(file_priv, dev, args->size,
415 						 &args->handle);
416 
417 	return PTR_ERR_OR_ZERO(rk_obj);
418 }
419 
420 /*
421  * Allocate a sg_table for this GEM object.
422  * Note: Both the table's contents, and the sg_table itself must be freed by
423  *       the caller.
424  * Returns a pointer to the newly allocated sg_table, or an ERR_PTR() error.
425  */
426 struct sg_table *rockchip_gem_prime_get_sg_table(struct drm_gem_object *obj)
427 {
428 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
429 	struct drm_device *drm = obj->dev;
430 	struct sg_table *sgt;
431 	int ret;
432 
433 	if (rk_obj->pages)
434 		return drm_prime_pages_to_sg(obj->dev, rk_obj->pages, rk_obj->num_pages);
435 
436 	sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
437 	if (!sgt)
438 		return ERR_PTR(-ENOMEM);
439 
440 	ret = dma_get_sgtable_attrs(drm->dev, sgt, rk_obj->kvaddr,
441 				    rk_obj->dma_addr, obj->size,
442 				    rk_obj->dma_attrs);
443 	if (ret) {
444 		DRM_ERROR("failed to allocate sgt, %d\n", ret);
445 		kfree(sgt);
446 		return ERR_PTR(ret);
447 	}
448 
449 	return sgt;
450 }
451 
452 static int
453 rockchip_gem_iommu_map_sg(struct drm_device *drm,
454 			  struct dma_buf_attachment *attach,
455 			  struct sg_table *sg,
456 			  struct rockchip_gem_object *rk_obj)
457 {
458 	rk_obj->sgt = sg;
459 	return rockchip_gem_iommu_map(rk_obj);
460 }
461 
462 static int
463 rockchip_gem_dma_map_sg(struct drm_device *drm,
464 			struct dma_buf_attachment *attach,
465 			struct sg_table *sg,
466 			struct rockchip_gem_object *rk_obj)
467 {
468 	int err = dma_map_sgtable(drm->dev, sg, DMA_BIDIRECTIONAL, 0);
469 	if (err)
470 		return err;
471 
472 	if (drm_prime_get_contiguous_size(sg) < attach->dmabuf->size) {
473 		DRM_ERROR("failed to map sg_table to contiguous linear address.\n");
474 		dma_unmap_sgtable(drm->dev, sg, DMA_BIDIRECTIONAL, 0);
475 		return -EINVAL;
476 	}
477 
478 	rk_obj->dma_addr = sg_dma_address(sg->sgl);
479 	rk_obj->sgt = sg;
480 	return 0;
481 }
482 
483 struct drm_gem_object *
484 rockchip_gem_prime_import_sg_table(struct drm_device *drm,
485 				   struct dma_buf_attachment *attach,
486 				   struct sg_table *sg)
487 {
488 	struct rockchip_drm_private *private = drm->dev_private;
489 	struct rockchip_gem_object *rk_obj;
490 	int ret;
491 
492 	rk_obj = rockchip_gem_alloc_object(drm, attach->dmabuf->size);
493 	if (IS_ERR(rk_obj))
494 		return ERR_CAST(rk_obj);
495 
496 	if (private->domain)
497 		ret = rockchip_gem_iommu_map_sg(drm, attach, sg, rk_obj);
498 	else
499 		ret = rockchip_gem_dma_map_sg(drm, attach, sg, rk_obj);
500 
501 	if (ret < 0) {
502 		DRM_ERROR("failed to import sg table: %d\n", ret);
503 		goto err_free_rk_obj;
504 	}
505 
506 	return &rk_obj->base;
507 
508 err_free_rk_obj:
509 	rockchip_gem_release_object(rk_obj);
510 	return ERR_PTR(ret);
511 }
512 
513 int rockchip_gem_prime_vmap(struct drm_gem_object *obj, struct iosys_map *map)
514 {
515 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
516 
517 	if (rk_obj->pages) {
518 		void *vaddr;
519 
520 		if (rk_obj->kvaddr)
521 			vaddr = rk_obj->kvaddr;
522 		else
523 			vaddr = vmap(rk_obj->pages, rk_obj->num_pages, VM_MAP,
524 				     pgprot_writecombine(PAGE_KERNEL));
525 
526 		if (!vaddr)
527 			return -ENOMEM;
528 		iosys_map_set_vaddr(map, vaddr);
529 		return 0;
530 	}
531 
532 	if (rk_obj->dma_attrs & DMA_ATTR_NO_KERNEL_MAPPING)
533 		return -ENOMEM;
534 	iosys_map_set_vaddr(map, rk_obj->kvaddr);
535 
536 	return 0;
537 }
538 
539 void rockchip_gem_prime_vunmap(struct drm_gem_object *obj,
540 			       struct iosys_map *map)
541 {
542 	struct rockchip_gem_object *rk_obj = to_rockchip_obj(obj);
543 
544 	if (rk_obj->pages) {
545 		if (map->vaddr != rk_obj->kvaddr)
546 			vunmap(map->vaddr);
547 		return;
548 	}
549 
550 	/* Nothing to do if allocated by DMA mapping API. */
551 }
552