drivers/gpu/drm/etnaviv/etnaviv_mmu.c

   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
  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
  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
  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
 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
 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         lockdep_assert_held(&context->lock);
 128
 129         etnaviv_iommu_unmap(context, mapping->vram_node.start,
 130                             etnaviv_obj->sgt, etnaviv_obj->base.size);
 131         drm_mm_remove_node(&mapping->vram_node);
 132 }
 133
 134 static int etnaviv_iommu_find_iova(struct etnaviv_iommu_context *context,
 135                                    struct drm_mm_node *node, size_t size)
 136 {
 137         struct etnaviv_vram_mapping *free = NULL;
 138         enum drm_mm_insert_mode mode = DRM_MM_INSERT_LOW;
 139         int ret;
 140
 141         lockdep_assert_held(&context->lock);
 142
 143         while (1) {
 144                 struct etnaviv_vram_mapping *m, *n;
 145                 struct drm_mm_scan scan;
 146                 struct list_head list;
 147                 bool found;
 148
 149                 ret = drm_mm_insert_node_in_range(&context->mm, node,
 150                                                   size, 0, 0, 0, U64_MAX, mode);
 151                 if (ret != -ENOSPC)
 152                         break;
 153
 154                 /* Try to retire some entries */
 155                 drm_mm_scan_init(&scan, &context->mm, size, 0, 0, mode);
 156
 157                 found = 0;
 158                 INIT_LIST_HEAD(&list);
 159                 list_for_each_entry(free, &context->mappings, mmu_node) {
 160                         /* If this vram node has not been used, skip this. */
 161                         if (!free->vram_node.mm)
 162                                 continue;
 163
 164                         /*
 165                          * If the iova is pinned, then it's in-use,
 166                          * so we must keep its mapping.
 167                          */
 168                         if (free->use)
 169                                 continue;
 170
 171                         list_add(&free->scan_node, &list);
 172                         if (drm_mm_scan_add_block(&scan, &free->vram_node)) {
 173                                 found = true;
 174                                 break;
 175                         }
 176                 }
 177
 178                 if (!found) {
 179                         /* Nothing found, clean up and fail */
 180                         list_for_each_entry_safe(m, n, &list, scan_node)
 181                                 BUG_ON(drm_mm_scan_remove_block(&scan, &m->vram_node));
 182                         break;
 183                 }
 184
 185                 /*
 186                  * drm_mm does not allow any other operations while
 187                  * scanning, so we have to remove all blocks first.
 188                  * If drm_mm_scan_remove_block() returns false, we
 189                  * can leave the block pinned.
 190                  */
 191                 list_for_each_entry_safe(m, n, &list, scan_node)
 192                         if (!drm_mm_scan_remove_block(&scan, &m->vram_node))
 193                                 list_del_init(&m->scan_node);
 194
 195                 /*
 196                  * Unmap the blocks which need to be reaped from the MMU.
 197                  * Clear the mmu pointer to prevent the mapping_get finding
 198                  * this mapping.
 199                  */
 200                 list_for_each_entry_safe(m, n, &list, scan_node) {
 201                         etnaviv_iommu_remove_mapping(context, m);
 202                         etnaviv_iommu_context_put(m->context);
 203                         m->context = NULL;
 204                         list_del_init(&m->mmu_node);
 205                         list_del_init(&m->scan_node);
 206                 }
 207
 208                 mode = DRM_MM_INSERT_EVICT;
 209
 210                 /*
 211                  * We removed enough mappings so that the new allocation will
 212                  * succeed, retry the allocation one more time.
 213                  */
 214         }
 215
 216         return ret;
 217 }
 218
 219 static int etnaviv_iommu_insert_exact(struct etnaviv_iommu_context *context,
 220                    struct drm_mm_node *node, size_t size, u64 va)
 221 {
 222         lockdep_assert_held(&context->lock);
 223
 224         return drm_mm_insert_node_in_range(&context->mm, node, size, 0, 0, va,
 225                                            va + size, DRM_MM_INSERT_LOWEST);
 226 }
 227
 228 int etnaviv_iommu_map_gem(struct etnaviv_iommu_context *context,
 229         struct etnaviv_gem_object *etnaviv_obj, u32 memory_base,
 230         struct etnaviv_vram_mapping *mapping, u64 va)
 231 {
 232         struct sg_table *sgt = etnaviv_obj->sgt;
 233         struct drm_mm_node *node;
 234         int ret;
 235
 236         lockdep_assert_held(&etnaviv_obj->lock);
 237
 238         mutex_lock(&context->lock);
 239
 240         /* v1 MMU can optimize single entry (contiguous) scatterlists */
 241         if (context->global->version == ETNAVIV_IOMMU_V1 &&
 242             sgt->nents == 1 && !(etnaviv_obj->flags & ETNA_BO_FORCE_MMU)) {
 243                 u32 iova;
 244
 245                 iova = sg_dma_address(sgt->sgl) - memory_base;
 246                 if (iova < 0x80000000 - sg_dma_len(sgt->sgl)) {
 247                         mapping->iova = iova;
 248                         list_add_tail(&mapping->mmu_node, &context->mappings);
 249                         ret = 0;
 250                         goto unlock;
 251                 }
 252         }
 253
 254         node = &mapping->vram_node;
 255
 256         if (va)
 257                 ret = etnaviv_iommu_insert_exact(context, node,
 258                                                  etnaviv_obj->base.size, va);
 259         else
 260                 ret = etnaviv_iommu_find_iova(context, node,
 261                                               etnaviv_obj->base.size);
 262         if (ret < 0)
 263                 goto unlock;
 264
 265         mapping->iova = node->start;
 266         ret = etnaviv_iommu_map(context, node->start, sgt, etnaviv_obj->base.size,
 267                                 ETNAVIV_PROT_READ | ETNAVIV_PROT_WRITE);
 268
 269         if (ret < 0) {
 270                 drm_mm_remove_node(node);
 271                 goto unlock;
 272         }
 273
 274         list_add_tail(&mapping->mmu_node, &context->mappings);
 275         context->flush_seq++;
 276 unlock:
 277         mutex_unlock(&context->lock);
 278
 279         return ret;
 280 }
 281
 282 void etnaviv_iommu_unmap_gem(struct etnaviv_iommu_context *context,
 283         struct etnaviv_vram_mapping *mapping)
 284 {
 285         WARN_ON(mapping->use);
 286
 287         mutex_lock(&context->lock);
 288
 289         /* Bail if the mapping has been reaped by another thread */
 290         if (!mapping->context) {
 291                 mutex_unlock(&context->lock);
 292                 return;
 293         }
 294
 295         /* If the vram node is on the mm, unmap and remove the node */
 296         if (mapping->vram_node.mm == &context->mm)
 297                 etnaviv_iommu_remove_mapping(context, mapping);
 298
 299         list_del(&mapping->mmu_node);
 300         context->flush_seq++;
 301         mutex_unlock(&context->lock);
 302 }
 303
 304 static void etnaviv_iommu_context_free(struct kref *kref)
 305 {
 306         struct etnaviv_iommu_context *context =
 307                 container_of(kref, struct etnaviv_iommu_context, refcount);
 308
 309         etnaviv_cmdbuf_suballoc_unmap(context, &context->cmdbuf_mapping);
 310
 311         context->global->ops->free(context);
 312 }
 313 void etnaviv_iommu_context_put(struct etnaviv_iommu_context *context)
 314 {
 315         kref_put(&context->refcount, etnaviv_iommu_context_free);
 316 }
 317
 318 struct etnaviv_iommu_context *
 319 etnaviv_iommu_context_init(struct etnaviv_iommu_global *global,
 320                            struct etnaviv_cmdbuf_suballoc *suballoc)
 321 {
 322         struct etnaviv_iommu_context *ctx;
 323         int ret;
 324
 325         if (global->version == ETNAVIV_IOMMU_V1)
 326                 ctx = etnaviv_iommuv1_context_alloc(global);
 327         else
 328                 ctx = etnaviv_iommuv2_context_alloc(global);
 329
 330         if (!ctx)
 331                 return NULL;
 332
 333         ret = etnaviv_cmdbuf_suballoc_map(suballoc, ctx, &ctx->cmdbuf_mapping,
 334                                           global->memory_base);
 335         if (ret)
 336                 goto out_free;
 337
 338         if (global->version == ETNAVIV_IOMMU_V1 &&
 339             ctx->cmdbuf_mapping.iova > 0x80000000) {
 340                 dev_err(global->dev,
 341                         "command buffer outside valid memory window\n");
 342                 goto out_unmap;
 343         }
 344
 345         return ctx;
 346
 347 out_unmap:
 348         etnaviv_cmdbuf_suballoc_unmap(ctx, &ctx->cmdbuf_mapping);
 349 out_free:
 350         global->ops->free(ctx);
 351         return NULL;
 352 }
 353
 354 void etnaviv_iommu_restore(struct etnaviv_gpu *gpu,
 355                            struct etnaviv_iommu_context *context)
 356 {
 357         context->global->ops->restore(gpu, context);
 358 }
 359
 360 int etnaviv_iommu_get_suballoc_va(struct etnaviv_iommu_context *context,
 361                                   struct etnaviv_vram_mapping *mapping,
 362                                   u32 memory_base, dma_addr_t paddr,
 363                                   size_t size)
 364 {
 365         mutex_lock(&context->lock);
 366
 367         if (mapping->use > 0) {
 368                 mapping->use++;
 369                 mutex_unlock(&context->lock);
 370                 return 0;
 371         }
 372
 373         /*
 374          * For MMUv1 we don't add the suballoc region to the pagetables, as
 375          * those GPUs can only work with cmdbufs accessed through the linear
 376          * window. Instead we manufacture a mapping to make it look uniform
 377          * to the upper layers.
 378          */
 379         if (context->global->version == ETNAVIV_IOMMU_V1) {
 380                 mapping->iova = paddr - memory_base;
 381         } else {
 382                 struct drm_mm_node *node = &mapping->vram_node;
 383                 int ret;
 384
 385                 ret = etnaviv_iommu_find_iova(context, node, size);
 386                 if (ret < 0) {
 387                         mutex_unlock(&context->lock);
 388                         return ret;
 389                 }
 390
 391                 mapping->iova = node->start;
 392                 ret = etnaviv_context_map(context, node->start, paddr, size,
 393                                           ETNAVIV_PROT_READ);
 394                 if (ret < 0) {
 395                         drm_mm_remove_node(node);
 396                         mutex_unlock(&context->lock);
 397                         return ret;
 398                 }
 399
 400                 context->flush_seq++;
 401         }
 402
 403         list_add_tail(&mapping->mmu_node, &context->mappings);
 404         mapping->use = 1;
 405
 406         mutex_unlock(&context->lock);
 407
 408         return 0;
 409 }
 410
 411 void etnaviv_iommu_put_suballoc_va(struct etnaviv_iommu_context *context,
 412                   struct etnaviv_vram_mapping *mapping)
 413 {
 414         struct drm_mm_node *node = &mapping->vram_node;
 415
 416         mutex_lock(&context->lock);
 417         mapping->use--;
 418
 419         if (mapping->use > 0 || context->global->version == ETNAVIV_IOMMU_V1) {
 420                 mutex_unlock(&context->lock);
 421                 return;
 422         }
 423
 424         etnaviv_context_unmap(context, node->start, node->size);
 425         drm_mm_remove_node(node);
 426         mutex_unlock(&context->lock);
 427 }
 428
 429 size_t etnaviv_iommu_dump_size(struct etnaviv_iommu_context *context)
 430 {
 431         return context->global->ops->dump_size(context);
 432 }
 433
 434 void etnaviv_iommu_dump(struct etnaviv_iommu_context *context, void *buf)
 435 {
 436         context->global->ops->dump(context, buf);
 437 }
 438
 439 int etnaviv_iommu_global_init(struct etnaviv_gpu *gpu)
 440 {
 441         enum etnaviv_iommu_version version = ETNAVIV_IOMMU_V1;
 442         struct etnaviv_drm_private *priv = gpu->drm->dev_private;
 443         struct etnaviv_iommu_global *global;
 444         struct device *dev = gpu->drm->dev;
 445
 446         if (gpu->identity.minor_features1 & chipMinorFeatures1_MMU_VERSION)
 447                 version = ETNAVIV_IOMMU_V2;
 448
 449         if (priv->mmu_global) {
 450                 if (priv->mmu_global->version != version) {
 451                         dev_err(gpu->dev,
 452                                 "MMU version doesn't match global version\n");
 453                         return -ENXIO;
 454                 }
 455
 456                 priv->mmu_global->use++;
 457                 return 0;
 458         }
 459
 460         global = kzalloc(sizeof(*global), GFP_KERNEL);
 461         if (!global)
 462                 return -ENOMEM;
 463
 464         global->bad_page_cpu = dma_alloc_wc(dev, SZ_4K, &global->bad_page_dma,
 465                                             GFP_KERNEL);
 466         if (!global->bad_page_cpu)
 467                 goto free_global;
 468
 469         memset32(global->bad_page_cpu, 0xdead55aa, SZ_4K / sizeof(u32));
 470
 471         if (version == ETNAVIV_IOMMU_V2) {
 472                 global->v2.pta_cpu = dma_alloc_wc(dev, ETNAVIV_PTA_SIZE,
 473                                                &global->v2.pta_dma, GFP_KERNEL);
 474                 if (!global->v2.pta_cpu)
 475                         goto free_bad_page;
 476         }
 477
 478         global->dev = dev;
 479         global->version = version;
 480         global->use = 1;
 481         mutex_init(&global->lock);
 482
 483         if (version == ETNAVIV_IOMMU_V1)
 484                 global->ops = &etnaviv_iommuv1_ops;
 485         else
 486                 global->ops = &etnaviv_iommuv2_ops;
 487
 488         priv->mmu_global = global;
 489
 490         return 0;
 491
 492 free_bad_page:
 493         dma_free_wc(dev, SZ_4K, global->bad_page_cpu, global->bad_page_dma);
 494 free_global:
 495         kfree(global);
 496
 497         return -ENOMEM;
 498 }
 499
 500 void etnaviv_iommu_global_fini(struct etnaviv_gpu *gpu)
 501 {
 502         struct etnaviv_drm_private *priv = gpu->drm->dev_private;
 503         struct etnaviv_iommu_global *global = priv->mmu_global;
 504
 505         if (--global->use > 0)
 506                 return;
 507
 508         if (global->v2.pta_cpu)
 509                 dma_free_wc(global->dev, ETNAVIV_PTA_SIZE,
 510                             global->v2.pta_cpu, global->v2.pta_dma);
 511
 512         if (global->bad_page_cpu)
 513                 dma_free_wc(global->dev, SZ_4K,
 514                             global->bad_page_cpu, global->bad_page_dma);
 515
 516         mutex_destroy(&global->lock);
 517         kfree(global);
 518
 519         priv->mmu_global = NULL;
 520 }