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                         mapping->context = etnaviv_iommu_context_get(context);
 249                         list_add_tail(&mapping->mmu_node, &context->mappings);
 250                         ret = 0;
 251                         goto unlock;
 252                 }
 253         }
 254
 255         node = &mapping->vram_node;
 256
 257         if (va)
 258                 ret = etnaviv_iommu_insert_exact(context, node,
 259                                                  etnaviv_obj->base.size, va);
 260         else
 261                 ret = etnaviv_iommu_find_iova(context, node,
 262                                               etnaviv_obj->base.size);
 263         if (ret < 0)
 264                 goto unlock;
 265
 266         mapping->iova = node->start;
 267         ret = etnaviv_iommu_map(context, node->start, sgt, etnaviv_obj->base.size,
 268                                 ETNAVIV_PROT_READ | ETNAVIV_PROT_WRITE);
 269
 270         if (ret < 0) {
 271                 drm_mm_remove_node(node);
 272                 goto unlock;
 273         }
 274
 275         mapping->context = etnaviv_iommu_context_get(context);
 276         list_add_tail(&mapping->mmu_node, &context->mappings);
 277         context->flush_seq++;
 278 unlock:
 279         mutex_unlock(&context->lock);
 280
 281         return ret;
 282 }
 283
 284 void etnaviv_iommu_unmap_gem(struct etnaviv_iommu_context *context,
 285         struct etnaviv_vram_mapping *mapping)
 286 {
 287         WARN_ON(mapping->use);
 288
 289         mutex_lock(&context->lock);
 290
 291         /* Bail if the mapping has been reaped by another thread */
 292         if (!mapping->context) {
 293                 mutex_unlock(&context->lock);
 294                 return;
 295         }
 296
 297         /* If the vram node is on the mm, unmap and remove the node */
 298         if (mapping->vram_node.mm == &context->mm)
 299                 etnaviv_iommu_remove_mapping(context, mapping);
 300
 301         list_del(&mapping->mmu_node);
 302         context->flush_seq++;
 303         mutex_unlock(&context->lock);
 304         etnaviv_iommu_context_put(context);
 305 }
 306
 307 static void etnaviv_iommu_context_free(struct kref *kref)
 308 {
 309         struct etnaviv_iommu_context *context =
 310                 container_of(kref, struct etnaviv_iommu_context, refcount);
 311
 312         etnaviv_cmdbuf_suballoc_unmap(context, &context->cmdbuf_mapping);
 313
 314         context->global->ops->free(context);
 315 }
 316 void etnaviv_iommu_context_put(struct etnaviv_iommu_context *context)
 317 {
 318         kref_put(&context->refcount, etnaviv_iommu_context_free);
 319 }
 320
 321 struct etnaviv_iommu_context *
 322 etnaviv_iommu_context_init(struct etnaviv_iommu_global *global,
 323                            struct etnaviv_cmdbuf_suballoc *suballoc)
 324 {
 325         struct etnaviv_iommu_context *ctx;
 326         int ret;
 327
 328         if (global->version == ETNAVIV_IOMMU_V1)
 329                 ctx = etnaviv_iommuv1_context_alloc(global);
 330         else
 331                 ctx = etnaviv_iommuv2_context_alloc(global);
 332
 333         if (!ctx)
 334                 return NULL;
 335
 336         ret = etnaviv_cmdbuf_suballoc_map(suballoc, ctx, &ctx->cmdbuf_mapping,
 337                                           global->memory_base);
 338         if (ret)
 339                 goto out_free;
 340
 341         if (global->version == ETNAVIV_IOMMU_V1 &&
 342             ctx->cmdbuf_mapping.iova > 0x80000000) {
 343                 dev_err(global->dev,
 344                         "command buffer outside valid memory window\n");
 345                 goto out_unmap;
 346         }
 347
 348         return ctx;
 349
 350 out_unmap:
 351         etnaviv_cmdbuf_suballoc_unmap(ctx, &ctx->cmdbuf_mapping);
 352 out_free:
 353         global->ops->free(ctx);
 354         return NULL;
 355 }
 356
 357 void etnaviv_iommu_restore(struct etnaviv_gpu *gpu,
 358                            struct etnaviv_iommu_context *context)
 359 {
 360         context->global->ops->restore(gpu, context);
 361 }
 362
 363 int etnaviv_iommu_get_suballoc_va(struct etnaviv_iommu_context *context,
 364                                   struct etnaviv_vram_mapping *mapping,
 365                                   u32 memory_base, dma_addr_t paddr,
 366                                   size_t size)
 367 {
 368         mutex_lock(&context->lock);
 369
 370         if (mapping->use > 0) {
 371                 mapping->use++;
 372                 mutex_unlock(&context->lock);
 373                 return 0;
 374         }
 375
 376         /*
 377          * For MMUv1 we don't add the suballoc region to the pagetables, as
 378          * those GPUs can only work with cmdbufs accessed through the linear
 379          * window. Instead we manufacture a mapping to make it look uniform
 380          * to the upper layers.
 381          */
 382         if (context->global->version == ETNAVIV_IOMMU_V1) {
 383                 mapping->iova = paddr - memory_base;
 384         } else {
 385                 struct drm_mm_node *node = &mapping->vram_node;
 386                 int ret;
 387
 388                 ret = etnaviv_iommu_find_iova(context, node, size);
 389                 if (ret < 0) {
 390                         mutex_unlock(&context->lock);
 391                         return ret;
 392                 }
 393
 394                 mapping->iova = node->start;
 395                 ret = etnaviv_context_map(context, node->start, paddr, size,
 396                                           ETNAVIV_PROT_READ);
 397                 if (ret < 0) {
 398                         drm_mm_remove_node(node);
 399                         mutex_unlock(&context->lock);
 400                         return ret;
 401                 }
 402
 403                 context->flush_seq++;
 404         }
 405
 406         list_add_tail(&mapping->mmu_node, &context->mappings);
 407         mapping->use = 1;
 408
 409         mutex_unlock(&context->lock);
 410
 411         return 0;
 412 }
 413
 414 void etnaviv_iommu_put_suballoc_va(struct etnaviv_iommu_context *context,
 415                   struct etnaviv_vram_mapping *mapping)
 416 {
 417         struct drm_mm_node *node = &mapping->vram_node;
 418
 419         mutex_lock(&context->lock);
 420         mapping->use--;
 421
 422         if (mapping->use > 0 || context->global->version == ETNAVIV_IOMMU_V1) {
 423                 mutex_unlock(&context->lock);
 424                 return;
 425         }
 426
 427         etnaviv_context_unmap(context, node->start, node->size);
 428         drm_mm_remove_node(node);
 429         mutex_unlock(&context->lock);
 430 }
 431
 432 size_t etnaviv_iommu_dump_size(struct etnaviv_iommu_context *context)
 433 {
 434         return context->global->ops->dump_size(context);
 435 }
 436
 437 void etnaviv_iommu_dump(struct etnaviv_iommu_context *context, void *buf)
 438 {
 439         context->global->ops->dump(context, buf);
 440 }
 441
 442 int etnaviv_iommu_global_init(struct etnaviv_gpu *gpu)
 443 {
 444         enum etnaviv_iommu_version version = ETNAVIV_IOMMU_V1;
 445         struct etnaviv_drm_private *priv = gpu->drm->dev_private;
 446         struct etnaviv_iommu_global *global;
 447         struct device *dev = gpu->drm->dev;
 448
 449         if (gpu->identity.minor_features1 & chipMinorFeatures1_MMU_VERSION)
 450                 version = ETNAVIV_IOMMU_V2;
 451
 452         if (priv->mmu_global) {
 453                 if (priv->mmu_global->version != version) {
 454                         dev_err(gpu->dev,
 455                                 "MMU version doesn't match global version\n");
 456                         return -ENXIO;
 457                 }
 458
 459                 priv->mmu_global->use++;
 460                 return 0;
 461         }
 462
 463         global = kzalloc(sizeof(*global), GFP_KERNEL);
 464         if (!global)
 465                 return -ENOMEM;
 466
 467         global->bad_page_cpu = dma_alloc_wc(dev, SZ_4K, &global->bad_page_dma,
 468                                             GFP_KERNEL);
 469         if (!global->bad_page_cpu)
 470                 goto free_global;
 471
 472         memset32(global->bad_page_cpu, 0xdead55aa, SZ_4K / sizeof(u32));
 473
 474         if (version == ETNAVIV_IOMMU_V2) {
 475                 global->v2.pta_cpu = dma_alloc_wc(dev, ETNAVIV_PTA_SIZE,
 476                                                &global->v2.pta_dma, GFP_KERNEL);
 477                 if (!global->v2.pta_cpu)
 478                         goto free_bad_page;
 479         }
 480
 481         global->dev = dev;
 482         global->version = version;
 483         global->use = 1;
 484         mutex_init(&global->lock);
 485
 486         if (version == ETNAVIV_IOMMU_V1)
 487                 global->ops = &etnaviv_iommuv1_ops;
 488         else
 489                 global->ops = &etnaviv_iommuv2_ops;
 490
 491         priv->mmu_global = global;
 492
 493         return 0;
 494
 495 free_bad_page:
 496         dma_free_wc(dev, SZ_4K, global->bad_page_cpu, global->bad_page_dma);
 497 free_global:
 498         kfree(global);
 499
 500         return -ENOMEM;
 501 }
 502
 503 void etnaviv_iommu_global_fini(struct etnaviv_gpu *gpu)
 504 {
 505         struct etnaviv_drm_private *priv = gpu->drm->dev_private;
 506         struct etnaviv_iommu_global *global = priv->mmu_global;
 507
 508         if (--global->use > 0)
 509                 return;
 510
 511         if (global->v2.pta_cpu)
 512                 dma_free_wc(global->dev, ETNAVIV_PTA_SIZE,
 513                             global->v2.pta_cpu, global->v2.pta_dma);
 514
 515         if (global->bad_page_cpu)
 516                 dma_free_wc(global->dev, SZ_4K,
 517                             global->bad_page_cpu, global->bad_page_dma);
 518
 519         mutex_destroy(&global->lock);
 520         kfree(global);
 521
 522         priv->mmu_global = NULL;
 523 }