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
16static 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
39static 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, iova: orig_iova, size: orig_size - size);
68
69 return ret;
70}
71
72static int etnaviv_iommu_map(struct etnaviv_iommu_context *context, u32 iova,
73 struct sg_table *sgt, 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 phys_addr_t pa = sg_dma_address(sg) - sg->offset;
84 size_t bytes = sg_dma_len(sg) + sg->offset;
85
86 VERB("map[%d]: %08x %pap(%zx)", i, iova, &pa, bytes);
87
88 ret = etnaviv_context_map(context, iova: da, paddr: pa, size: bytes, prot);
89 if (ret)
90 goto fail;
91
92 da += bytes;
93 }
94
95 context->flush_seq++;
96
97 return 0;
98
99fail:
100 etnaviv_context_unmap(context, iova, size: da - iova);
101 return ret;
102}
103
104static void etnaviv_iommu_unmap(struct etnaviv_iommu_context *context, u32 iova,
105 struct sg_table *sgt, unsigned len)
106{
107 struct scatterlist *sg;
108 unsigned int da = iova;
109 int i;
110
111 for_each_sgtable_dma_sg(sgt, sg, i) {
112 size_t bytes = sg_dma_len(sg) + sg->offset;
113
114 etnaviv_context_unmap(context, iova: da, size: bytes);
115
116 VERB("unmap[%d]: %08x(%zx)", i, iova, bytes);
117
118 BUG_ON(!PAGE_ALIGNED(bytes));
119
120 da += bytes;
121 }
122
123 context->flush_seq++;
124}
125
126static void etnaviv_iommu_remove_mapping(struct etnaviv_iommu_context *context,
127 struct etnaviv_vram_mapping *mapping)
128{
129 struct etnaviv_gem_object *etnaviv_obj = mapping->object;
130
131 lockdep_assert_held(&context->lock);
132
133 etnaviv_iommu_unmap(context, iova: mapping->vram_node.start,
134 sgt: etnaviv_obj->sgt, len: etnaviv_obj->base.size);
135 drm_mm_remove_node(node: &mapping->vram_node);
136}
137
138void etnaviv_iommu_reap_mapping(struct etnaviv_vram_mapping *mapping)
139{
140 struct etnaviv_iommu_context *context = mapping->context;
141
142 lockdep_assert_held(&context->lock);
143 WARN_ON(mapping->use);
144
145 etnaviv_iommu_remove_mapping(context, mapping);
146 etnaviv_iommu_context_put(ctx: mapping->context);
147 mapping->context = NULL;
148 list_del_init(entry: &mapping->mmu_node);
149}
150
151static int etnaviv_iommu_find_iova(struct etnaviv_iommu_context *context,
152 struct drm_mm_node *node, size_t size)
153{
154 struct etnaviv_vram_mapping *free = NULL;
155 enum drm_mm_insert_mode mode = DRM_MM_INSERT_LOW;
156 int ret;
157
158 lockdep_assert_held(&context->lock);
159
160 while (1) {
161 struct etnaviv_vram_mapping *m, *n;
162 struct drm_mm_scan scan;
163 struct list_head list;
164 bool found;
165
166 ret = drm_mm_insert_node_in_range(mm: &context->mm, node,
167 size, alignment: 0, color: 0, start: 0, U64_MAX, mode);
168 if (ret != -ENOSPC)
169 break;
170
171 /* Try to retire some entries */
172 drm_mm_scan_init(scan: &scan, mm: &context->mm, size, alignment: 0, color: 0, mode);
173
174 found = 0;
175 INIT_LIST_HEAD(list: &list);
176 list_for_each_entry(free, &context->mappings, mmu_node) {
177 /* If this vram node has not been used, skip this. */
178 if (!free->vram_node.mm)
179 continue;
180
181 /*
182 * If the iova is pinned, then it's in-use,
183 * so we must keep its mapping.
184 */
185 if (free->use)
186 continue;
187
188 list_add(new: &free->scan_node, head: &list);
189 if (drm_mm_scan_add_block(scan: &scan, node: &free->vram_node)) {
190 found = true;
191 break;
192 }
193 }
194
195 if (!found) {
196 /* Nothing found, clean up and fail */
197 list_for_each_entry_safe(m, n, &list, scan_node)
198 BUG_ON(drm_mm_scan_remove_block(&scan, &m->vram_node));
199 break;
200 }
201
202 /*
203 * drm_mm does not allow any other operations while
204 * scanning, so we have to remove all blocks first.
205 * If drm_mm_scan_remove_block() returns false, we
206 * can leave the block pinned.
207 */
208 list_for_each_entry_safe(m, n, &list, scan_node)
209 if (!drm_mm_scan_remove_block(scan: &scan, node: &m->vram_node))
210 list_del_init(entry: &m->scan_node);
211
212 /*
213 * Unmap the blocks which need to be reaped from the MMU.
214 * Clear the mmu pointer to prevent the mapping_get finding
215 * this mapping.
216 */
217 list_for_each_entry_safe(m, n, &list, scan_node) {
218 etnaviv_iommu_reap_mapping(mapping: m);
219 list_del_init(entry: &m->scan_node);
220 }
221
222 mode = DRM_MM_INSERT_EVICT;
223
224 /*
225 * We removed enough mappings so that the new allocation will
226 * succeed, retry the allocation one more time.
227 */
228 }
229
230 return ret;
231}
232
233static int etnaviv_iommu_insert_exact(struct etnaviv_iommu_context *context,
234 struct drm_mm_node *node, size_t size, u64 va)
235{
236 struct etnaviv_vram_mapping *m, *n;
237 struct drm_mm_node *scan_node;
238 LIST_HEAD(scan_list);
239 int ret;
240
241 lockdep_assert_held(&context->lock);
242
243 ret = drm_mm_insert_node_in_range(mm: &context->mm, node, size, alignment: 0, color: 0, start: va,
244 end: va + size, mode: DRM_MM_INSERT_LOWEST);
245 if (ret != -ENOSPC)
246 return ret;
247
248 /*
249 * When we can't insert the node, due to a existing mapping blocking
250 * the address space, there are two possible reasons:
251 * 1. Userspace genuinely messed up and tried to reuse address space
252 * before the last job using this VMA has finished executing.
253 * 2. The existing buffer mappings are idle, but the buffers are not
254 * destroyed yet (likely due to being referenced by another context) in
255 * which case the mappings will not be cleaned up and we must reap them
256 * here to make space for the new mapping.
257 */
258
259 drm_mm_for_each_node_in_range(scan_node, &context->mm, va, va + size) {
260 m = container_of(scan_node, struct etnaviv_vram_mapping,
261 vram_node);
262
263 if (m->use)
264 return -ENOSPC;
265
266 list_add(new: &m->scan_node, head: &scan_list);
267 }
268
269 list_for_each_entry_safe(m, n, &scan_list, scan_node) {
270 etnaviv_iommu_reap_mapping(mapping: m);
271 list_del_init(entry: &m->scan_node);
272 }
273
274 return drm_mm_insert_node_in_range(mm: &context->mm, node, size, alignment: 0, color: 0, start: va,
275 end: va + size, mode: DRM_MM_INSERT_LOWEST);
276}
277
278int etnaviv_iommu_map_gem(struct etnaviv_iommu_context *context,
279 struct etnaviv_gem_object *etnaviv_obj, u32 memory_base,
280 struct etnaviv_vram_mapping *mapping, u64 va)
281{
282 struct sg_table *sgt = etnaviv_obj->sgt;
283 struct drm_mm_node *node;
284 int ret;
285
286 lockdep_assert_held(&etnaviv_obj->lock);
287
288 mutex_lock(&context->lock);
289
290 /* v1 MMU can optimize single entry (contiguous) scatterlists */
291 if (context->global->version == ETNAVIV_IOMMU_V1 &&
292 sgt->nents == 1 && !(etnaviv_obj->flags & ETNA_BO_FORCE_MMU)) {
293 u32 iova;
294
295 iova = sg_dma_address(sgt->sgl) - memory_base;
296 if (iova < 0x80000000 - sg_dma_len(sgt->sgl)) {
297 mapping->iova = iova;
298 mapping->context = etnaviv_iommu_context_get(ctx: context);
299 list_add_tail(new: &mapping->mmu_node, head: &context->mappings);
300 ret = 0;
301 goto unlock;
302 }
303 }
304
305 node = &mapping->vram_node;
306
307 if (va)
308 ret = etnaviv_iommu_insert_exact(context, node,
309 size: etnaviv_obj->base.size, va);
310 else
311 ret = etnaviv_iommu_find_iova(context, node,
312 size: etnaviv_obj->base.size);
313 if (ret < 0)
314 goto unlock;
315
316 mapping->iova = node->start;
317 ret = etnaviv_iommu_map(context, iova: node->start, sgt,
318 ETNAVIV_PROT_READ | ETNAVIV_PROT_WRITE);
319
320 if (ret < 0) {
321 drm_mm_remove_node(node);
322 goto unlock;
323 }
324
325 mapping->context = etnaviv_iommu_context_get(ctx: context);
326 list_add_tail(new: &mapping->mmu_node, head: &context->mappings);
327unlock:
328 mutex_unlock(lock: &context->lock);
329
330 return ret;
331}
332
333void etnaviv_iommu_unmap_gem(struct etnaviv_iommu_context *context,
334 struct etnaviv_vram_mapping *mapping)
335{
336 WARN_ON(mapping->use);
337
338 mutex_lock(&context->lock);
339
340 /* Bail if the mapping has been reaped by another thread */
341 if (!mapping->context) {
342 mutex_unlock(lock: &context->lock);
343 return;
344 }
345
346 /* If the vram node is on the mm, unmap and remove the node */
347 if (mapping->vram_node.mm == &context->mm)
348 etnaviv_iommu_remove_mapping(context, mapping);
349
350 list_del(entry: &mapping->mmu_node);
351 mutex_unlock(lock: &context->lock);
352 etnaviv_iommu_context_put(ctx: context);
353}
354
355static void etnaviv_iommu_context_free(struct kref *kref)
356{
357 struct etnaviv_iommu_context *context =
358 container_of(kref, struct etnaviv_iommu_context, refcount);
359
360 etnaviv_cmdbuf_suballoc_unmap(context, mapping: &context->cmdbuf_mapping);
361
362 context->global->ops->free(context);
363}
364void etnaviv_iommu_context_put(struct etnaviv_iommu_context *context)
365{
366 kref_put(kref: &context->refcount, release: etnaviv_iommu_context_free);
367}
368
369struct etnaviv_iommu_context *
370etnaviv_iommu_context_init(struct etnaviv_iommu_global *global,
371 struct etnaviv_cmdbuf_suballoc *suballoc)
372{
373 struct etnaviv_iommu_context *ctx;
374 int ret;
375
376 if (global->version == ETNAVIV_IOMMU_V1)
377 ctx = etnaviv_iommuv1_context_alloc(global);
378 else
379 ctx = etnaviv_iommuv2_context_alloc(global);
380
381 if (!ctx)
382 return NULL;
383
384 ret = etnaviv_cmdbuf_suballoc_map(suballoc, context: ctx, mapping: &ctx->cmdbuf_mapping,
385 memory_base: global->memory_base);
386 if (ret)
387 goto out_free;
388
389 if (global->version == ETNAVIV_IOMMU_V1 &&
390 ctx->cmdbuf_mapping.iova > 0x80000000) {
391 dev_err(global->dev,
392 "command buffer outside valid memory window\n");
393 goto out_unmap;
394 }
395
396 return ctx;
397
398out_unmap:
399 etnaviv_cmdbuf_suballoc_unmap(context: ctx, mapping: &ctx->cmdbuf_mapping);
400out_free:
401 global->ops->free(ctx);
402 return NULL;
403}
404
405void etnaviv_iommu_restore(struct etnaviv_gpu *gpu,
406 struct etnaviv_iommu_context *context)
407{
408 context->global->ops->restore(gpu, context);
409}
410
411int etnaviv_iommu_get_suballoc_va(struct etnaviv_iommu_context *context,
412 struct etnaviv_vram_mapping *mapping,
413 u32 memory_base, dma_addr_t paddr,
414 size_t size)
415{
416 mutex_lock(&context->lock);
417
418 if (mapping->use > 0) {
419 mapping->use++;
420 mutex_unlock(lock: &context->lock);
421 return 0;
422 }
423
424 /*
425 * For MMUv1 we don't add the suballoc region to the pagetables, as
426 * those GPUs can only work with cmdbufs accessed through the linear
427 * window. Instead we manufacture a mapping to make it look uniform
428 * to the upper layers.
429 */
430 if (context->global->version == ETNAVIV_IOMMU_V1) {
431 mapping->iova = paddr - memory_base;
432 } else {
433 struct drm_mm_node *node = &mapping->vram_node;
434 int ret;
435
436 ret = etnaviv_iommu_find_iova(context, node, size);
437 if (ret < 0) {
438 mutex_unlock(lock: &context->lock);
439 return ret;
440 }
441
442 mapping->iova = node->start;
443 ret = etnaviv_context_map(context, iova: node->start, paddr, size,
444 ETNAVIV_PROT_READ);
445 if (ret < 0) {
446 drm_mm_remove_node(node);
447 mutex_unlock(lock: &context->lock);
448 return ret;
449 }
450
451 context->flush_seq++;
452 }
453
454 list_add_tail(new: &mapping->mmu_node, head: &context->mappings);
455 mapping->use = 1;
456
457 mutex_unlock(lock: &context->lock);
458
459 return 0;
460}
461
462void etnaviv_iommu_put_suballoc_va(struct etnaviv_iommu_context *context,
463 struct etnaviv_vram_mapping *mapping)
464{
465 struct drm_mm_node *node = &mapping->vram_node;
466
467 mutex_lock(&context->lock);
468 mapping->use--;
469
470 if (mapping->use > 0 || context->global->version == ETNAVIV_IOMMU_V1) {
471 mutex_unlock(lock: &context->lock);
472 return;
473 }
474
475 etnaviv_context_unmap(context, iova: node->start, size: node->size);
476 drm_mm_remove_node(node);
477 mutex_unlock(lock: &context->lock);
478}
479
480size_t etnaviv_iommu_dump_size(struct etnaviv_iommu_context *context)
481{
482 return context->global->ops->dump_size(context);
483}
484
485void etnaviv_iommu_dump(struct etnaviv_iommu_context *context, void *buf)
486{
487 context->global->ops->dump(context, buf);
488}
489
490int etnaviv_iommu_global_init(struct etnaviv_gpu *gpu)
491{
492 enum etnaviv_iommu_version version = ETNAVIV_IOMMU_V1;
493 struct etnaviv_drm_private *priv = gpu->drm->dev_private;
494 struct etnaviv_iommu_global *global;
495 struct device *dev = gpu->drm->dev;
496
497 if (gpu->identity.minor_features1 & chipMinorFeatures1_MMU_VERSION)
498 version = ETNAVIV_IOMMU_V2;
499
500 if (priv->mmu_global) {
501 if (priv->mmu_global->version != version) {
502 dev_err(gpu->dev,
503 "MMU version doesn't match global version\n");
504 return -ENXIO;
505 }
506
507 priv->mmu_global->use++;
508 return 0;
509 }
510
511 global = kzalloc(size: sizeof(*global), GFP_KERNEL);
512 if (!global)
513 return -ENOMEM;
514
515 global->bad_page_cpu = dma_alloc_wc(dev, SZ_4K, dma_addr: &global->bad_page_dma,
516 GFP_KERNEL);
517 if (!global->bad_page_cpu)
518 goto free_global;
519
520 memset32(s: global->bad_page_cpu, v: 0xdead55aa, SZ_4K / sizeof(u32));
521
522 if (version == ETNAVIV_IOMMU_V2) {
523 global->v2.pta_cpu = dma_alloc_wc(dev, ETNAVIV_PTA_SIZE,
524 dma_addr: &global->v2.pta_dma, GFP_KERNEL);
525 if (!global->v2.pta_cpu)
526 goto free_bad_page;
527 }
528
529 global->dev = dev;
530 global->version = version;
531 global->use = 1;
532 mutex_init(&global->lock);
533
534 if (version == ETNAVIV_IOMMU_V1)
535 global->ops = &etnaviv_iommuv1_ops;
536 else
537 global->ops = &etnaviv_iommuv2_ops;
538
539 priv->mmu_global = global;
540
541 return 0;
542
543free_bad_page:
544 dma_free_wc(dev, SZ_4K, cpu_addr: global->bad_page_cpu, dma_addr: global->bad_page_dma);
545free_global:
546 kfree(objp: global);
547
548 return -ENOMEM;
549}
550
551void etnaviv_iommu_global_fini(struct etnaviv_gpu *gpu)
552{
553 struct etnaviv_drm_private *priv = gpu->drm->dev_private;
554 struct etnaviv_iommu_global *global = priv->mmu_global;
555
556 if (!global)
557 return;
558
559 if (--global->use > 0)
560 return;
561
562 if (global->v2.pta_cpu)
563 dma_free_wc(dev: global->dev, ETNAVIV_PTA_SIZE,
564 cpu_addr: global->v2.pta_cpu, dma_addr: global->v2.pta_dma);
565
566 if (global->bad_page_cpu)
567 dma_free_wc(dev: global->dev, SZ_4K,
568 cpu_addr: global->bad_page_cpu, dma_addr: global->bad_page_dma);
569
570 mutex_destroy(lock: &global->lock);
571 kfree(objp: global);
572
573 priv->mmu_global = NULL;
574}
575

source code of linux/drivers/gpu/drm/etnaviv/etnaviv_mmu.c