1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2015-2018 Etnaviv Project
4  */
5 
6 #include <linux/dma-mapping.h>
7 #include <linux/scatterlist.h>
8 
9 #include "common.xml.h"
10 #include "etnaviv_cmdbuf.h"
11 #include "etnaviv_drv.h"
12 #include "etnaviv_gem.h"
13 #include "etnaviv_gpu.h"
14 #include "etnaviv_mmu.h"
15 
etnaviv_context_unmap(struct etnaviv_iommu_context * context,unsigned long iova,size_t size)16 static void etnaviv_context_unmap(struct etnaviv_iommu_context *context,
17 				 unsigned long iova, size_t size)
18 {
19 	size_t unmapped_page, unmapped = 0;
20 	size_t pgsize = SZ_4K;
21 
22 	if (!IS_ALIGNED(iova | size, pgsize)) {
23 		pr_err("unaligned: iova 0x%lx size 0x%zx min_pagesz 0x%zx\n",
24 		       iova, size, pgsize);
25 		return;
26 	}
27 
28 	while (unmapped < size) {
29 		unmapped_page = context->global->ops->unmap(context, iova,
30 							    pgsize);
31 		if (!unmapped_page)
32 			break;
33 
34 		iova += unmapped_page;
35 		unmapped += unmapped_page;
36 	}
37 }
38 
etnaviv_context_map(struct etnaviv_iommu_context * context,unsigned long iova,phys_addr_t paddr,size_t size,int prot)39 static int etnaviv_context_map(struct etnaviv_iommu_context *context,
40 			      unsigned long iova, phys_addr_t paddr,
41 			      size_t size, int prot)
42 {
43 	unsigned long orig_iova = iova;
44 	size_t pgsize = SZ_4K;
45 	size_t orig_size = size;
46 	int ret = 0;
47 
48 	if (!IS_ALIGNED(iova | paddr | size, pgsize)) {
49 		pr_err("unaligned: iova 0x%lx pa %pa size 0x%zx min_pagesz 0x%zx\n",
50 		       iova, &paddr, size, pgsize);
51 		return -EINVAL;
52 	}
53 
54 	while (size) {
55 		ret = context->global->ops->map(context, iova, paddr, pgsize,
56 						prot);
57 		if (ret)
58 			break;
59 
60 		iova += pgsize;
61 		paddr += pgsize;
62 		size -= pgsize;
63 	}
64 
65 	/* unroll mapping in case something went wrong */
66 	if (ret)
67 		etnaviv_context_unmap(context, orig_iova, orig_size - size);
68 
69 	return ret;
70 }
71 
etnaviv_iommu_map(struct etnaviv_iommu_context * context,u32 iova,struct sg_table * sgt,unsigned len,int prot)72 static int etnaviv_iommu_map(struct etnaviv_iommu_context *context, u32 iova,
73 			     struct sg_table *sgt, unsigned len, int prot)
74 {	struct scatterlist *sg;
75 	unsigned int da = iova;
76 	unsigned int i;
77 	int ret;
78 
79 	if (!context || !sgt)
80 		return -EINVAL;
81 
82 	for_each_sgtable_dma_sg(sgt, sg, i) {
83 		u32 pa = sg_dma_address(sg) - sg->offset;
84 		size_t bytes = sg_dma_len(sg) + sg->offset;
85 
86 		VERB("map[%d]: %08x %08x(%zx)", i, iova, pa, bytes);
87 
88 		ret = etnaviv_context_map(context, da, pa, bytes, prot);
89 		if (ret)
90 			goto fail;
91 
92 		da += bytes;
93 	}
94 
95 	return 0;
96 
97 fail:
98 	etnaviv_context_unmap(context, iova, da - iova);
99 	return ret;
100 }
101 
etnaviv_iommu_unmap(struct etnaviv_iommu_context * context,u32 iova,struct sg_table * sgt,unsigned len)102 static void etnaviv_iommu_unmap(struct etnaviv_iommu_context *context, u32 iova,
103 				struct sg_table *sgt, unsigned len)
104 {
105 	struct scatterlist *sg;
106 	unsigned int da = iova;
107 	int i;
108 
109 	for_each_sgtable_dma_sg(sgt, sg, i) {
110 		size_t bytes = sg_dma_len(sg) + sg->offset;
111 
112 		etnaviv_context_unmap(context, da, bytes);
113 
114 		VERB("unmap[%d]: %08x(%zx)", i, iova, bytes);
115 
116 		BUG_ON(!PAGE_ALIGNED(bytes));
117 
118 		da += bytes;
119 	}
120 }
121 
etnaviv_iommu_remove_mapping(struct etnaviv_iommu_context * context,struct etnaviv_vram_mapping * mapping)122 static void etnaviv_iommu_remove_mapping(struct etnaviv_iommu_context *context,
123 	struct etnaviv_vram_mapping *mapping)
124 {
125 	struct etnaviv_gem_object *etnaviv_obj = mapping->object;
126 
127 	etnaviv_iommu_unmap(context, mapping->vram_node.start,
128 			    etnaviv_obj->sgt, etnaviv_obj->base.size);
129 	drm_mm_remove_node(&mapping->vram_node);
130 }
131 
etnaviv_iommu_find_iova(struct etnaviv_iommu_context * context,struct drm_mm_node * node,size_t size)132 static int etnaviv_iommu_find_iova(struct etnaviv_iommu_context *context,
133 				   struct drm_mm_node *node, size_t size)
134 {
135 	struct etnaviv_vram_mapping *free = NULL;
136 	enum drm_mm_insert_mode mode = DRM_MM_INSERT_LOW;
137 	int ret;
138 
139 	lockdep_assert_held(&context->lock);
140 
141 	while (1) {
142 		struct etnaviv_vram_mapping *m, *n;
143 		struct drm_mm_scan scan;
144 		struct list_head list;
145 		bool found;
146 
147 		ret = drm_mm_insert_node_in_range(&context->mm, node,
148 						  size, 0, 0, 0, U64_MAX, mode);
149 		if (ret != -ENOSPC)
150 			break;
151 
152 		/* Try to retire some entries */
153 		drm_mm_scan_init(&scan, &context->mm, size, 0, 0, mode);
154 
155 		found = 0;
156 		INIT_LIST_HEAD(&list);
157 		list_for_each_entry(free, &context->mappings, mmu_node) {
158 			/* If this vram node has not been used, skip this. */
159 			if (!free->vram_node.mm)
160 				continue;
161 
162 			/*
163 			 * If the iova is pinned, then it's in-use,
164 			 * so we must keep its mapping.
165 			 */
166 			if (free->use)
167 				continue;
168 
169 			list_add(&free->scan_node, &list);
170 			if (drm_mm_scan_add_block(&scan, &free->vram_node)) {
171 				found = true;
172 				break;
173 			}
174 		}
175 
176 		if (!found) {
177 			/* Nothing found, clean up and fail */
178 			list_for_each_entry_safe(m, n, &list, scan_node)
179 				BUG_ON(drm_mm_scan_remove_block(&scan, &m->vram_node));
180 			break;
181 		}
182 
183 		/*
184 		 * drm_mm does not allow any other operations while
185 		 * scanning, so we have to remove all blocks first.
186 		 * If drm_mm_scan_remove_block() returns false, we
187 		 * can leave the block pinned.
188 		 */
189 		list_for_each_entry_safe(m, n, &list, scan_node)
190 			if (!drm_mm_scan_remove_block(&scan, &m->vram_node))
191 				list_del_init(&m->scan_node);
192 
193 		/*
194 		 * Unmap the blocks which need to be reaped from the MMU.
195 		 * Clear the mmu pointer to prevent the mapping_get finding
196 		 * this mapping.
197 		 */
198 		list_for_each_entry_safe(m, n, &list, scan_node) {
199 			etnaviv_iommu_remove_mapping(context, m);
200 			m->context = NULL;
201 			list_del_init(&m->mmu_node);
202 			list_del_init(&m->scan_node);
203 		}
204 
205 		mode = DRM_MM_INSERT_EVICT;
206 
207 		/*
208 		 * We removed enough mappings so that the new allocation will
209 		 * succeed, retry the allocation one more time.
210 		 */
211 	}
212 
213 	return ret;
214 }
215 
etnaviv_iommu_insert_exact(struct etnaviv_iommu_context * context,struct drm_mm_node * node,size_t size,u64 va)216 static int etnaviv_iommu_insert_exact(struct etnaviv_iommu_context *context,
217 		   struct drm_mm_node *node, size_t size, u64 va)
218 {
219 	return drm_mm_insert_node_in_range(&context->mm, node, size, 0, 0, va,
220 					   va + size, DRM_MM_INSERT_LOWEST);
221 }
222 
etnaviv_iommu_map_gem(struct etnaviv_iommu_context * context,struct etnaviv_gem_object * etnaviv_obj,u32 memory_base,struct etnaviv_vram_mapping * mapping,u64 va)223 int etnaviv_iommu_map_gem(struct etnaviv_iommu_context *context,
224 	struct etnaviv_gem_object *etnaviv_obj, u32 memory_base,
225 	struct etnaviv_vram_mapping *mapping, u64 va)
226 {
227 	struct sg_table *sgt = etnaviv_obj->sgt;
228 	struct drm_mm_node *node;
229 	int ret;
230 
231 	lockdep_assert_held(&etnaviv_obj->lock);
232 
233 	mutex_lock(&context->lock);
234 
235 	/* v1 MMU can optimize single entry (contiguous) scatterlists */
236 	if (context->global->version == ETNAVIV_IOMMU_V1 &&
237 	    sgt->nents == 1 && !(etnaviv_obj->flags & ETNA_BO_FORCE_MMU)) {
238 		u32 iova;
239 
240 		iova = sg_dma_address(sgt->sgl) - memory_base;
241 		if (iova < 0x80000000 - sg_dma_len(sgt->sgl)) {
242 			mapping->iova = iova;
243 			list_add_tail(&mapping->mmu_node, &context->mappings);
244 			ret = 0;
245 			goto unlock;
246 		}
247 	}
248 
249 	node = &mapping->vram_node;
250 
251 	if (va)
252 		ret = etnaviv_iommu_insert_exact(context, node,
253 						 etnaviv_obj->base.size, va);
254 	else
255 		ret = etnaviv_iommu_find_iova(context, node,
256 					      etnaviv_obj->base.size);
257 	if (ret < 0)
258 		goto unlock;
259 
260 	mapping->iova = node->start;
261 	ret = etnaviv_iommu_map(context, node->start, sgt, etnaviv_obj->base.size,
262 				ETNAVIV_PROT_READ | ETNAVIV_PROT_WRITE);
263 
264 	if (ret < 0) {
265 		drm_mm_remove_node(node);
266 		goto unlock;
267 	}
268 
269 	list_add_tail(&mapping->mmu_node, &context->mappings);
270 	context->flush_seq++;
271 unlock:
272 	mutex_unlock(&context->lock);
273 
274 	return ret;
275 }
276 
etnaviv_iommu_unmap_gem(struct etnaviv_iommu_context * context,struct etnaviv_vram_mapping * mapping)277 void etnaviv_iommu_unmap_gem(struct etnaviv_iommu_context *context,
278 	struct etnaviv_vram_mapping *mapping)
279 {
280 	WARN_ON(mapping->use);
281 
282 	mutex_lock(&context->lock);
283 
284 	/* If the vram node is on the mm, unmap and remove the node */
285 	if (mapping->vram_node.mm == &context->mm)
286 		etnaviv_iommu_remove_mapping(context, mapping);
287 
288 	list_del(&mapping->mmu_node);
289 	context->flush_seq++;
290 	mutex_unlock(&context->lock);
291 }
292 
etnaviv_iommu_context_free(struct kref * kref)293 static void etnaviv_iommu_context_free(struct kref *kref)
294 {
295 	struct etnaviv_iommu_context *context =
296 		container_of(kref, struct etnaviv_iommu_context, refcount);
297 
298 	etnaviv_cmdbuf_suballoc_unmap(context, &context->cmdbuf_mapping);
299 
300 	context->global->ops->free(context);
301 }
etnaviv_iommu_context_put(struct etnaviv_iommu_context * context)302 void etnaviv_iommu_context_put(struct etnaviv_iommu_context *context)
303 {
304 	kref_put(&context->refcount, etnaviv_iommu_context_free);
305 }
306 
307 struct etnaviv_iommu_context *
etnaviv_iommu_context_init(struct etnaviv_iommu_global * global,struct etnaviv_cmdbuf_suballoc * suballoc)308 etnaviv_iommu_context_init(struct etnaviv_iommu_global *global,
309 			   struct etnaviv_cmdbuf_suballoc *suballoc)
310 {
311 	struct etnaviv_iommu_context *ctx;
312 	int ret;
313 
314 	if (global->version == ETNAVIV_IOMMU_V1)
315 		ctx = etnaviv_iommuv1_context_alloc(global);
316 	else
317 		ctx = etnaviv_iommuv2_context_alloc(global);
318 
319 	if (!ctx)
320 		return NULL;
321 
322 	ret = etnaviv_cmdbuf_suballoc_map(suballoc, ctx, &ctx->cmdbuf_mapping,
323 					  global->memory_base);
324 	if (ret)
325 		goto out_free;
326 
327 	if (global->version == ETNAVIV_IOMMU_V1 &&
328 	    ctx->cmdbuf_mapping.iova > 0x80000000) {
329 		dev_err(global->dev,
330 		        "command buffer outside valid memory window\n");
331 		goto out_unmap;
332 	}
333 
334 	return ctx;
335 
336 out_unmap:
337 	etnaviv_cmdbuf_suballoc_unmap(ctx, &ctx->cmdbuf_mapping);
338 out_free:
339 	global->ops->free(ctx);
340 	return NULL;
341 }
342 
etnaviv_iommu_restore(struct etnaviv_gpu * gpu,struct etnaviv_iommu_context * context)343 void etnaviv_iommu_restore(struct etnaviv_gpu *gpu,
344 			   struct etnaviv_iommu_context *context)
345 {
346 	context->global->ops->restore(gpu, context);
347 }
348 
etnaviv_iommu_get_suballoc_va(struct etnaviv_iommu_context * context,struct etnaviv_vram_mapping * mapping,u32 memory_base,dma_addr_t paddr,size_t size)349 int etnaviv_iommu_get_suballoc_va(struct etnaviv_iommu_context *context,
350 				  struct etnaviv_vram_mapping *mapping,
351 				  u32 memory_base, dma_addr_t paddr,
352 				  size_t size)
353 {
354 	mutex_lock(&context->lock);
355 
356 	if (mapping->use > 0) {
357 		mapping->use++;
358 		mutex_unlock(&context->lock);
359 		return 0;
360 	}
361 
362 	/*
363 	 * For MMUv1 we don't add the suballoc region to the pagetables, as
364 	 * those GPUs can only work with cmdbufs accessed through the linear
365 	 * window. Instead we manufacture a mapping to make it look uniform
366 	 * to the upper layers.
367 	 */
368 	if (context->global->version == ETNAVIV_IOMMU_V1) {
369 		mapping->iova = paddr - memory_base;
370 	} else {
371 		struct drm_mm_node *node = &mapping->vram_node;
372 		int ret;
373 
374 		ret = etnaviv_iommu_find_iova(context, node, size);
375 		if (ret < 0) {
376 			mutex_unlock(&context->lock);
377 			return ret;
378 		}
379 
380 		mapping->iova = node->start;
381 		ret = etnaviv_context_map(context, node->start, paddr, size,
382 					  ETNAVIV_PROT_READ);
383 		if (ret < 0) {
384 			drm_mm_remove_node(node);
385 			mutex_unlock(&context->lock);
386 			return ret;
387 		}
388 
389 		context->flush_seq++;
390 	}
391 
392 	list_add_tail(&mapping->mmu_node, &context->mappings);
393 	mapping->use = 1;
394 
395 	mutex_unlock(&context->lock);
396 
397 	return 0;
398 }
399 
etnaviv_iommu_put_suballoc_va(struct etnaviv_iommu_context * context,struct etnaviv_vram_mapping * mapping)400 void etnaviv_iommu_put_suballoc_va(struct etnaviv_iommu_context *context,
401 		  struct etnaviv_vram_mapping *mapping)
402 {
403 	struct drm_mm_node *node = &mapping->vram_node;
404 
405 	mutex_lock(&context->lock);
406 	mapping->use--;
407 
408 	if (mapping->use > 0 || context->global->version == ETNAVIV_IOMMU_V1) {
409 		mutex_unlock(&context->lock);
410 		return;
411 	}
412 
413 	etnaviv_context_unmap(context, node->start, node->size);
414 	drm_mm_remove_node(node);
415 	mutex_unlock(&context->lock);
416 }
417 
etnaviv_iommu_dump_size(struct etnaviv_iommu_context * context)418 size_t etnaviv_iommu_dump_size(struct etnaviv_iommu_context *context)
419 {
420 	return context->global->ops->dump_size(context);
421 }
422 
etnaviv_iommu_dump(struct etnaviv_iommu_context * context,void * buf)423 void etnaviv_iommu_dump(struct etnaviv_iommu_context *context, void *buf)
424 {
425 	context->global->ops->dump(context, buf);
426 }
427 
etnaviv_iommu_global_init(struct etnaviv_gpu * gpu)428 int etnaviv_iommu_global_init(struct etnaviv_gpu *gpu)
429 {
430 	enum etnaviv_iommu_version version = ETNAVIV_IOMMU_V1;
431 	struct etnaviv_drm_private *priv = gpu->drm->dev_private;
432 	struct etnaviv_iommu_global *global;
433 	struct device *dev = gpu->drm->dev;
434 
435 	if (gpu->identity.minor_features1 & chipMinorFeatures1_MMU_VERSION)
436 		version = ETNAVIV_IOMMU_V2;
437 
438 	if (priv->mmu_global) {
439 		if (priv->mmu_global->version != version) {
440 			dev_err(gpu->dev,
441 				"MMU version doesn't match global version\n");
442 			return -ENXIO;
443 		}
444 
445 		priv->mmu_global->use++;
446 		return 0;
447 	}
448 
449 	global = kzalloc(sizeof(*global), GFP_KERNEL);
450 	if (!global)
451 		return -ENOMEM;
452 
453 	global->bad_page_cpu = dma_alloc_wc(dev, SZ_4K, &global->bad_page_dma,
454 					    GFP_KERNEL);
455 	if (!global->bad_page_cpu)
456 		goto free_global;
457 
458 	memset32(global->bad_page_cpu, 0xdead55aa, SZ_4K / sizeof(u32));
459 
460 	if (version == ETNAVIV_IOMMU_V2) {
461 		global->v2.pta_cpu = dma_alloc_wc(dev, ETNAVIV_PTA_SIZE,
462 					       &global->v2.pta_dma, GFP_KERNEL);
463 		if (!global->v2.pta_cpu)
464 			goto free_bad_page;
465 	}
466 
467 	global->dev = dev;
468 	global->version = version;
469 	global->use = 1;
470 	mutex_init(&global->lock);
471 
472 	if (version == ETNAVIV_IOMMU_V1)
473 		global->ops = &etnaviv_iommuv1_ops;
474 	else
475 		global->ops = &etnaviv_iommuv2_ops;
476 
477 	priv->mmu_global = global;
478 
479 	return 0;
480 
481 free_bad_page:
482 	dma_free_wc(dev, SZ_4K, global->bad_page_cpu, global->bad_page_dma);
483 free_global:
484 	kfree(global);
485 
486 	return -ENOMEM;
487 }
488 
etnaviv_iommu_global_fini(struct etnaviv_gpu * gpu)489 void etnaviv_iommu_global_fini(struct etnaviv_gpu *gpu)
490 {
491 	struct etnaviv_drm_private *priv = gpu->drm->dev_private;
492 	struct etnaviv_iommu_global *global = priv->mmu_global;
493 
494 	if (--global->use > 0)
495 		return;
496 
497 	if (global->v2.pta_cpu)
498 		dma_free_wc(global->dev, ETNAVIV_PTA_SIZE,
499 			    global->v2.pta_cpu, global->v2.pta_dma);
500 
501 	if (global->bad_page_cpu)
502 		dma_free_wc(global->dev, SZ_4K,
503 			    global->bad_page_cpu, global->bad_page_dma);
504 
505 	mutex_destroy(&global->lock);
506 	kfree(global);
507 
508 	priv->mmu_global = NULL;
509 }
510