drivers/gpu/drm/amd/amdkfd/kfd_topology.c

   1 /*
   2  * Copyright 2014 Advanced Micro Devices, Inc.
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  20  * OTHER DEALINGS IN THE SOFTWARE.
  21  */
  22
  23 #include <linux/types.h>
  24 #include <linux/kernel.h>
  25 #include <linux/pci.h>
  26 #include <linux/errno.h>
  27 #include <linux/acpi.h>
  28 #include <linux/hash.h>
  29 #include <linux/cpufreq.h>
  30 #include <linux/log2.h>
  31
  32 #include "kfd_priv.h"
  33 #include "kfd_crat.h"
  34 #include "kfd_topology.h"
  35
  36 static struct list_head topology_device_list;
  37 static int topology_crat_parsed;
  38 static struct kfd_system_properties sys_props;
  39
  40 static DECLARE_RWSEM(topology_lock);
  41
  42 struct kfd_dev *kfd_device_by_id(uint32_t gpu_id)
  43 {
  44         struct kfd_topology_device *top_dev;
  45         struct kfd_dev *device = NULL;
  46
  47         down_read(&topology_lock);
  48
  49         list_for_each_entry(top_dev, &topology_device_list, list)
  50                 if (top_dev->gpu_id == gpu_id) {
  51                         device = top_dev->gpu;
  52                         break;
  53                 }
  54
  55         up_read(&topology_lock);
  56
  57         return device;
  58 }
  59
  60 struct kfd_dev *kfd_device_by_pci_dev(const struct pci_dev *pdev)
  61 {
  62         struct kfd_topology_device *top_dev;
  63         struct kfd_dev *device = NULL;
  64
  65         down_read(&topology_lock);
  66
  67         list_for_each_entry(top_dev, &topology_device_list, list)
  68                 if (top_dev->gpu->pdev == pdev) {
  69                         device = top_dev->gpu;
  70                         break;
  71                 }
  72
  73         up_read(&topology_lock);
  74
  75         return device;
  76 }
  77
  78 static int kfd_topology_get_crat_acpi(void *crat_image, size_t *size)
  79 {
  80         struct acpi_table_header *crat_table;
  81         acpi_status status;
  82
  83         if (!size)
  84                 return -EINVAL;
  85
  86         /*
  87          * Fetch the CRAT table from ACPI
  88          */
  89         status = acpi_get_table(CRAT_SIGNATURE, 0, &crat_table);
  90         if (status == AE_NOT_FOUND) {
  91                 pr_warn("CRAT table not found\n");
  92                 return -ENODATA;
  93         } else if (ACPI_FAILURE(status)) {
  94                 const char *err = acpi_format_exception(status);
  95
  96                 pr_err("CRAT table error: %s\n", err);
  97                 return -EINVAL;
  98         }
  99
 100         if (*size >= crat_table->length && crat_image != NULL)
 101                 memcpy(crat_image, crat_table, crat_table->length);
 102
 103         *size = crat_table->length;
 104
 105         return 0;
 106 }
 107
 108 static void kfd_populated_cu_info_cpu(struct kfd_topology_device *dev,
 109                 struct crat_subtype_computeunit *cu)
 110 {
 111         BUG_ON(!dev);
 112         BUG_ON(!cu);
 113
 114         dev->node_props.cpu_cores_count = cu->num_cpu_cores;
 115         dev->node_props.cpu_core_id_base = cu->processor_id_low;
 116         if (cu->hsa_capability & CRAT_CU_FLAGS_IOMMU_PRESENT)
 117                 dev->node_props.capability |= HSA_CAP_ATS_PRESENT;
 118
 119         pr_info("CU CPU: cores=%d id_base=%d\n", cu->num_cpu_cores,
 120                         cu->processor_id_low);
 121 }
 122
 123 static void kfd_populated_cu_info_gpu(struct kfd_topology_device *dev,
 124                 struct crat_subtype_computeunit *cu)
 125 {
 126         BUG_ON(!dev);
 127         BUG_ON(!cu);
 128
 129         dev->node_props.simd_id_base = cu->processor_id_low;
 130         dev->node_props.simd_count = cu->num_simd_cores;
 131         dev->node_props.lds_size_in_kb = cu->lds_size_in_kb;
 132         dev->node_props.max_waves_per_simd = cu->max_waves_simd;
 133         dev->node_props.wave_front_size = cu->wave_front_size;
 134         dev->node_props.mem_banks_count = cu->num_banks;
 135         dev->node_props.array_count = cu->num_arrays;
 136         dev->node_props.cu_per_simd_array = cu->num_cu_per_array;
 137         dev->node_props.simd_per_cu = cu->num_simd_per_cu;
 138         dev->node_props.max_slots_scratch_cu = cu->max_slots_scatch_cu;
 139         if (cu->hsa_capability & CRAT_CU_FLAGS_HOT_PLUGGABLE)
 140                 dev->node_props.capability |= HSA_CAP_HOT_PLUGGABLE;
 141         pr_info("CU GPU: simds=%d id_base=%d\n", cu->num_simd_cores,
 142                                 cu->processor_id_low);
 143 }
 144
 145 /* kfd_parse_subtype_cu is called when the topology mutex is already acquired */
 146 static int kfd_parse_subtype_cu(struct crat_subtype_computeunit *cu)
 147 {
 148         struct kfd_topology_device *dev;
 149         int i = 0;
 150
 151         BUG_ON(!cu);
 152
 153         pr_info("Found CU entry in CRAT table with proximity_domain=%d caps=%x\n",
 154                         cu->proximity_domain, cu->hsa_capability);
 155         list_for_each_entry(dev, &topology_device_list, list) {
 156                 if (cu->proximity_domain == i) {
 157                         if (cu->flags & CRAT_CU_FLAGS_CPU_PRESENT)
 158                                 kfd_populated_cu_info_cpu(dev, cu);
 159
 160                         if (cu->flags & CRAT_CU_FLAGS_GPU_PRESENT)
 161                                 kfd_populated_cu_info_gpu(dev, cu);
 162                         break;
 163                 }
 164                 i++;
 165         }
 166
 167         return 0;
 168 }
 169
 170 /*
 171  * kfd_parse_subtype_mem is called when the topology mutex is
 172  * already acquired
 173  */
 174 static int kfd_parse_subtype_mem(struct crat_subtype_memory *mem)
 175 {
 176         struct kfd_mem_properties *props;
 177         struct kfd_topology_device *dev;
 178         int i = 0;
 179
 180         BUG_ON(!mem);
 181
 182         pr_info("Found memory entry in CRAT table with proximity_domain=%d\n",
 183                         mem->promixity_domain);
 184         list_for_each_entry(dev, &topology_device_list, list) {
 185                 if (mem->promixity_domain == i) {
 186                         props = kfd_alloc_struct(props);
 187                         if (props == NULL)
 188                                 return -ENOMEM;
 189
 190                         if (dev->node_props.cpu_cores_count == 0)
 191                                 props->heap_type = HSA_MEM_HEAP_TYPE_FB_PRIVATE;
 192                         else
 193                                 props->heap_type = HSA_MEM_HEAP_TYPE_SYSTEM;
 194
 195                         if (mem->flags & CRAT_MEM_FLAGS_HOT_PLUGGABLE)
 196                                 props->flags |= HSA_MEM_FLAGS_HOT_PLUGGABLE;
 197                         if (mem->flags & CRAT_MEM_FLAGS_NON_VOLATILE)
 198                                 props->flags |= HSA_MEM_FLAGS_NON_VOLATILE;
 199
 200                         props->size_in_bytes =
 201                                 ((uint64_t)mem->length_high << 32) +
 202                                                         mem->length_low;
 203                         props->width = mem->width;
 204
 205                         dev->mem_bank_count++;
 206                         list_add_tail(&props->list, &dev->mem_props);
 207
 208                         break;
 209                 }
 210                 i++;
 211         }
 212
 213         return 0;
 214 }
 215
 216 /*
 217  * kfd_parse_subtype_cache is called when the topology mutex
 218  * is already acquired
 219  */
 220 static int kfd_parse_subtype_cache(struct crat_subtype_cache *cache)
 221 {
 222         struct kfd_cache_properties *props;
 223         struct kfd_topology_device *dev;
 224         uint32_t id;
 225
 226         BUG_ON(!cache);
 227
 228         id = cache->processor_id_low;
 229
 230         pr_info("Found cache entry in CRAT table with processor_id=%d\n", id);
 231         list_for_each_entry(dev, &topology_device_list, list)
 232                 if (id == dev->node_props.cpu_core_id_base ||
 233                     id == dev->node_props.simd_id_base) {
 234                         props = kfd_alloc_struct(props);
 235                         if (props == NULL)
 236                                 return -ENOMEM;
 237
 238                         props->processor_id_low = id;
 239                         props->cache_level = cache->cache_level;
 240                         props->cache_size = cache->cache_size;
 241                         props->cacheline_size = cache->cache_line_size;
 242                         props->cachelines_per_tag = cache->lines_per_tag;
 243                         props->cache_assoc = cache->associativity;
 244                         props->cache_latency = cache->cache_latency;
 245
 246                         if (cache->flags & CRAT_CACHE_FLAGS_DATA_CACHE)
 247                                 props->cache_type |= HSA_CACHE_TYPE_DATA;
 248                         if (cache->flags & CRAT_CACHE_FLAGS_INST_CACHE)
 249                                 props->cache_type |= HSA_CACHE_TYPE_INSTRUCTION;
 250                         if (cache->flags & CRAT_CACHE_FLAGS_CPU_CACHE)
 251                                 props->cache_type |= HSA_CACHE_TYPE_CPU;
 252                         if (cache->flags & CRAT_CACHE_FLAGS_SIMD_CACHE)
 253                                 props->cache_type |= HSA_CACHE_TYPE_HSACU;
 254
 255                         dev->cache_count++;
 256                         dev->node_props.caches_count++;
 257                         list_add_tail(&props->list, &dev->cache_props);
 258
 259                         break;
 260                 }
 261
 262         return 0;
 263 }
 264
 265 /*
 266  * kfd_parse_subtype_iolink is called when the topology mutex
 267  * is already acquired
 268  */
 269 static int kfd_parse_subtype_iolink(struct crat_subtype_iolink *iolink)
 270 {
 271         struct kfd_iolink_properties *props;
 272         struct kfd_topology_device *dev;
 273         uint32_t i = 0;
 274         uint32_t id_from;
 275         uint32_t id_to;
 276
 277         BUG_ON(!iolink);
 278
 279         id_from = iolink->proximity_domain_from;
 280         id_to = iolink->proximity_domain_to;
 281
 282         pr_info("Found IO link entry in CRAT table with id_from=%d\n", id_from);
 283         list_for_each_entry(dev, &topology_device_list, list) {
 284                 if (id_from == i) {
 285                         props = kfd_alloc_struct(props);
 286                         if (props == NULL)
 287                                 return -ENOMEM;
 288
 289                         props->node_from = id_from;
 290                         props->node_to = id_to;
 291                         props->ver_maj = iolink->version_major;
 292                         props->ver_min = iolink->version_minor;
 293
 294                         /*
 295                          * weight factor (derived from CDIR), currently always 1
 296                          */
 297                         props->weight = 1;
 298
 299                         props->min_latency = iolink->minimum_latency;
 300                         props->max_latency = iolink->maximum_latency;
 301                         props->min_bandwidth = iolink->minimum_bandwidth_mbs;
 302                         props->max_bandwidth = iolink->maximum_bandwidth_mbs;
 303                         props->rec_transfer_size =
 304                                         iolink->recommended_transfer_size;
 305
 306                         dev->io_link_count++;
 307                         dev->node_props.io_links_count++;
 308                         list_add_tail(&props->list, &dev->io_link_props);
 309
 310                         break;
 311                 }
 312                 i++;
 313         }
 314
 315         return 0;
 316 }
 317
 318 static int kfd_parse_subtype(struct crat_subtype_generic *sub_type_hdr)
 319 {
 320         struct crat_subtype_computeunit *cu;
 321         struct crat_subtype_memory *mem;
 322         struct crat_subtype_cache *cache;
 323         struct crat_subtype_iolink *iolink;
 324         int ret = 0;
 325
 326         BUG_ON(!sub_type_hdr);
 327
 328         switch (sub_type_hdr->type) {
 329         case CRAT_SUBTYPE_COMPUTEUNIT_AFFINITY:
 330                 cu = (struct crat_subtype_computeunit *)sub_type_hdr;
 331                 ret = kfd_parse_subtype_cu(cu);
 332                 break;
 333         case CRAT_SUBTYPE_MEMORY_AFFINITY:
 334                 mem = (struct crat_subtype_memory *)sub_type_hdr;
 335                 ret = kfd_parse_subtype_mem(mem);
 336                 break;
 337         case CRAT_SUBTYPE_CACHE_AFFINITY:
 338                 cache = (struct crat_subtype_cache *)sub_type_hdr;
 339                 ret = kfd_parse_subtype_cache(cache);
 340                 break;
 341         case CRAT_SUBTYPE_TLB_AFFINITY:
 342                 /*
 343                  * For now, nothing to do here
 344                  */
 345                 pr_info("Found TLB entry in CRAT table (not processing)\n");
 346                 break;
 347         case CRAT_SUBTYPE_CCOMPUTE_AFFINITY:
 348                 /*
 349                  * For now, nothing to do here
 350                  */
 351                 pr_info("Found CCOMPUTE entry in CRAT table (not processing)\n");
 352                 break;
 353         case CRAT_SUBTYPE_IOLINK_AFFINITY:
 354                 iolink = (struct crat_subtype_iolink *)sub_type_hdr;
 355                 ret = kfd_parse_subtype_iolink(iolink);
 356                 break;
 357         default:
 358                 pr_warn("Unknown subtype (%d) in CRAT\n",
 359                                 sub_type_hdr->type);
 360         }
 361
 362         return ret;
 363 }
 364
 365 static void kfd_release_topology_device(struct kfd_topology_device *dev)
 366 {
 367         struct kfd_mem_properties *mem;
 368         struct kfd_cache_properties *cache;
 369         struct kfd_iolink_properties *iolink;
 370
 371         BUG_ON(!dev);
 372
 373         list_del(&dev->list);
 374
 375         while (dev->mem_props.next != &dev->mem_props) {
 376                 mem = container_of(dev->mem_props.next,
 377                                 struct kfd_mem_properties, list);
 378                 list_del(&mem->list);
 379                 kfree(mem);
 380         }
 381
 382         while (dev->cache_props.next != &dev->cache_props) {
 383                 cache = container_of(dev->cache_props.next,
 384                                 struct kfd_cache_properties, list);
 385                 list_del(&cache->list);
 386                 kfree(cache);
 387         }
 388
 389         while (dev->io_link_props.next != &dev->io_link_props) {
 390                 iolink = container_of(dev->io_link_props.next,
 391                                 struct kfd_iolink_properties, list);
 392                 list_del(&iolink->list);
 393                 kfree(iolink);
 394         }
 395
 396         kfree(dev);
 397
 398         sys_props.num_devices--;
 399 }
 400
 401 static void kfd_release_live_view(void)
 402 {
 403         struct kfd_topology_device *dev;
 404
 405         while (topology_device_list.next != &topology_device_list) {
 406                 dev = container_of(topology_device_list.next,
 407                                  struct kfd_topology_device, list);
 408                 kfd_release_topology_device(dev);
 409 }
 410
 411         memset(&sys_props, 0, sizeof(sys_props));
 412 }
 413
 414 static struct kfd_topology_device *kfd_create_topology_device(void)
 415 {
 416         struct kfd_topology_device *dev;
 417
 418         dev = kfd_alloc_struct(dev);
 419         if (dev == NULL) {
 420                 pr_err("No memory to allocate a topology device");
 421                 return NULL;
 422         }
 423
 424         INIT_LIST_HEAD(&dev->mem_props);
 425         INIT_LIST_HEAD(&dev->cache_props);
 426         INIT_LIST_HEAD(&dev->io_link_props);
 427
 428         list_add_tail(&dev->list, &topology_device_list);
 429         sys_props.num_devices++;
 430
 431         return dev;
 432 }
 433
 434 static int kfd_parse_crat_table(void *crat_image)
 435 {
 436         struct kfd_topology_device *top_dev;
 437         struct crat_subtype_generic *sub_type_hdr;
 438         uint16_t node_id;
 439         int ret;
 440         struct crat_header *crat_table = (struct crat_header *)crat_image;
 441         uint16_t num_nodes;
 442         uint32_t image_len;
 443
 444         if (!crat_image)
 445                 return -EINVAL;
 446
 447         num_nodes = crat_table->num_domains;
 448         image_len = crat_table->length;
 449
 450         pr_info("Parsing CRAT table with %d nodes\n", num_nodes);
 451
 452         for (node_id = 0; node_id < num_nodes; node_id++) {
 453                 top_dev = kfd_create_topology_device();
 454                 if (!top_dev) {
 455                         kfd_release_live_view();
 456                         return -ENOMEM;
 457                 }
 458         }
 459
 460         sys_props.platform_id =
 461                 (*((uint64_t *)crat_table->oem_id)) & CRAT_OEMID_64BIT_MASK;
 462         sys_props.platform_oem = *((uint64_t *)crat_table->oem_table_id);
 463         sys_props.platform_rev = crat_table->revision;
 464
 465         sub_type_hdr = (struct crat_subtype_generic *)(crat_table+1);
 466         while ((char *)sub_type_hdr + sizeof(struct crat_subtype_generic) <
 467                         ((char *)crat_image) + image_len) {
 468                 if (sub_type_hdr->flags & CRAT_SUBTYPE_FLAGS_ENABLED) {
 469                         ret = kfd_parse_subtype(sub_type_hdr);
 470                         if (ret != 0) {
 471                                 kfd_release_live_view();
 472                                 return ret;
 473                         }
 474                 }
 475
 476                 sub_type_hdr = (typeof(sub_type_hdr))((char *)sub_type_hdr +
 477                                 sub_type_hdr->length);
 478         }
 479
 480         sys_props.generation_count++;
 481         topology_crat_parsed = 1;
 482
 483         return 0;
 484 }
 485
 486
 487 #define sysfs_show_gen_prop(buffer, fmt, ...) \
 488                 snprintf(buffer, PAGE_SIZE, "%s"fmt, buffer, __VA_ARGS__)
 489 #define sysfs_show_32bit_prop(buffer, name, value) \
 490                 sysfs_show_gen_prop(buffer, "%s %u\n", name, value)
 491 #define sysfs_show_64bit_prop(buffer, name, value) \
 492                 sysfs_show_gen_prop(buffer, "%s %llu\n", name, value)
 493 #define sysfs_show_32bit_val(buffer, value) \
 494                 sysfs_show_gen_prop(buffer, "%u\n", value)
 495 #define sysfs_show_str_val(buffer, value) \
 496                 sysfs_show_gen_prop(buffer, "%s\n", value)
 497
 498 static ssize_t sysprops_show(struct kobject *kobj, struct attribute *attr,
 499                 char *buffer)
 500 {
 501         ssize_t ret;
 502
 503         /* Making sure that the buffer is an empty string */
 504         buffer[0] = 0;
 505
 506         if (attr == &sys_props.attr_genid) {
 507                 ret = sysfs_show_32bit_val(buffer, sys_props.generation_count);
 508         } else if (attr == &sys_props.attr_props) {
 509                 sysfs_show_64bit_prop(buffer, "platform_oem",
 510                                 sys_props.platform_oem);
 511                 sysfs_show_64bit_prop(buffer, "platform_id",
 512                                 sys_props.platform_id);
 513                 ret = sysfs_show_64bit_prop(buffer, "platform_rev",
 514                                 sys_props.platform_rev);
 515         } else {
 516                 ret = -EINVAL;
 517         }
 518
 519         return ret;
 520 }
 521
 522 static void kfd_topology_kobj_release(struct kobject *kobj)
 523 {
 524         kfree(kobj);
 525 }
 526
 527 static const struct sysfs_ops sysprops_ops = {
 528         .show = sysprops_show,
 529 };
 530
 531 static struct kobj_type sysprops_type = {
 532         .release = kfd_topology_kobj_release,
 533         .sysfs_ops = &sysprops_ops,
 534 };
 535
 536 static ssize_t iolink_show(struct kobject *kobj, struct attribute *attr,
 537                 char *buffer)
 538 {
 539         ssize_t ret;
 540         struct kfd_iolink_properties *iolink;
 541
 542         /* Making sure that the buffer is an empty string */
 543         buffer[0] = 0;
 544
 545         iolink = container_of(attr, struct kfd_iolink_properties, attr);
 546         sysfs_show_32bit_prop(buffer, "type", iolink->iolink_type);
 547         sysfs_show_32bit_prop(buffer, "version_major", iolink->ver_maj);
 548         sysfs_show_32bit_prop(buffer, "version_minor", iolink->ver_min);
 549         sysfs_show_32bit_prop(buffer, "node_from", iolink->node_from);
 550         sysfs_show_32bit_prop(buffer, "node_to", iolink->node_to);
 551         sysfs_show_32bit_prop(buffer, "weight", iolink->weight);
 552         sysfs_show_32bit_prop(buffer, "min_latency", iolink->min_latency);
 553         sysfs_show_32bit_prop(buffer, "max_latency", iolink->max_latency);
 554         sysfs_show_32bit_prop(buffer, "min_bandwidth", iolink->min_bandwidth);
 555         sysfs_show_32bit_prop(buffer, "max_bandwidth", iolink->max_bandwidth);
 556         sysfs_show_32bit_prop(buffer, "recommended_transfer_size",
 557                         iolink->rec_transfer_size);
 558         ret = sysfs_show_32bit_prop(buffer, "flags", iolink->flags);
 559
 560         return ret;
 561 }
 562
 563 static const struct sysfs_ops iolink_ops = {
 564         .show = iolink_show,
 565 };
 566
 567 static struct kobj_type iolink_type = {
 568         .release = kfd_topology_kobj_release,
 569         .sysfs_ops = &iolink_ops,
 570 };
 571
 572 static ssize_t mem_show(struct kobject *kobj, struct attribute *attr,
 573                 char *buffer)
 574 {
 575         ssize_t ret;
 576         struct kfd_mem_properties *mem;
 577
 578         /* Making sure that the buffer is an empty string */
 579         buffer[0] = 0;
 580
 581         mem = container_of(attr, struct kfd_mem_properties, attr);
 582         sysfs_show_32bit_prop(buffer, "heap_type", mem->heap_type);
 583         sysfs_show_64bit_prop(buffer, "size_in_bytes", mem->size_in_bytes);
 584         sysfs_show_32bit_prop(buffer, "flags", mem->flags);
 585         sysfs_show_32bit_prop(buffer, "width", mem->width);
 586         ret = sysfs_show_32bit_prop(buffer, "mem_clk_max", mem->mem_clk_max);
 587
 588         return ret;
 589 }
 590
 591 static const struct sysfs_ops mem_ops = {
 592         .show = mem_show,
 593 };
 594
 595 static struct kobj_type mem_type = {
 596         .release = kfd_topology_kobj_release,
 597         .sysfs_ops = &mem_ops,
 598 };
 599
 600 static ssize_t kfd_cache_show(struct kobject *kobj, struct attribute *attr,
 601                 char *buffer)
 602 {
 603         ssize_t ret;
 604         uint32_t i;
 605         struct kfd_cache_properties *cache;
 606
 607         /* Making sure that the buffer is an empty string */
 608         buffer[0] = 0;
 609
 610         cache = container_of(attr, struct kfd_cache_properties, attr);
 611         sysfs_show_32bit_prop(buffer, "processor_id_low",
 612                         cache->processor_id_low);
 613         sysfs_show_32bit_prop(buffer, "level", cache->cache_level);
 614         sysfs_show_32bit_prop(buffer, "size", cache->cache_size);
 615         sysfs_show_32bit_prop(buffer, "cache_line_size", cache->cacheline_size);
 616         sysfs_show_32bit_prop(buffer, "cache_lines_per_tag",
 617                         cache->cachelines_per_tag);
 618         sysfs_show_32bit_prop(buffer, "association", cache->cache_assoc);
 619         sysfs_show_32bit_prop(buffer, "latency", cache->cache_latency);
 620         sysfs_show_32bit_prop(buffer, "type", cache->cache_type);
 621         snprintf(buffer, PAGE_SIZE, "%ssibling_map ", buffer);
 622         for (i = 0; i < KFD_TOPOLOGY_CPU_SIBLINGS; i++)
 623                 ret = snprintf(buffer, PAGE_SIZE, "%s%d%s",
 624                                 buffer, cache->sibling_map[i],
 625                                 (i == KFD_TOPOLOGY_CPU_SIBLINGS-1) ?
 626                                                 "\n" : ",");
 627
 628         return ret;
 629 }
 630
 631 static const struct sysfs_ops cache_ops = {
 632         .show = kfd_cache_show,
 633 };
 634
 635 static struct kobj_type cache_type = {
 636         .release = kfd_topology_kobj_release,
 637         .sysfs_ops = &cache_ops,
 638 };
 639
 640 static ssize_t node_show(struct kobject *kobj, struct attribute *attr,
 641                 char *buffer)
 642 {
 643         struct kfd_topology_device *dev;
 644         char public_name[KFD_TOPOLOGY_PUBLIC_NAME_SIZE];
 645         uint32_t i;
 646         uint32_t log_max_watch_addr;
 647
 648         /* Making sure that the buffer is an empty string */
 649         buffer[0] = 0;
 650
 651         if (strcmp(attr->name, "gpu_id") == 0) {
 652                 dev = container_of(attr, struct kfd_topology_device,
 653                                 attr_gpuid);
 654                 return sysfs_show_32bit_val(buffer, dev->gpu_id);
 655         }
 656
 657         if (strcmp(attr->name, "name") == 0) {
 658                 dev = container_of(attr, struct kfd_topology_device,
 659                                 attr_name);
 660                 for (i = 0; i < KFD_TOPOLOGY_PUBLIC_NAME_SIZE; i++) {
 661                         public_name[i] =
 662                                         (char)dev->node_props.marketing_name[i];
 663                         if (dev->node_props.marketing_name[i] == 0)
 664                                 break;
 665                 }
 666                 public_name[KFD_TOPOLOGY_PUBLIC_NAME_SIZE-1] = 0x0;
 667                 return sysfs_show_str_val(buffer, public_name);
 668         }
 669
 670         dev = container_of(attr, struct kfd_topology_device,
 671                         attr_props);
 672         sysfs_show_32bit_prop(buffer, "cpu_cores_count",
 673                         dev->node_props.cpu_cores_count);
 674         sysfs_show_32bit_prop(buffer, "simd_count",
 675                         dev->node_props.simd_count);
 676
 677         if (dev->mem_bank_count < dev->node_props.mem_banks_count) {
 678                 pr_warn("kfd: mem_banks_count truncated from %d to %d\n",
 679                                 dev->node_props.mem_banks_count,
 680                                 dev->mem_bank_count);
 681                 sysfs_show_32bit_prop(buffer, "mem_banks_count",
 682                                 dev->mem_bank_count);
 683         } else {
 684                 sysfs_show_32bit_prop(buffer, "mem_banks_count",
 685                                 dev->node_props.mem_banks_count);
 686         }
 687
 688         sysfs_show_32bit_prop(buffer, "caches_count",
 689                         dev->node_props.caches_count);
 690         sysfs_show_32bit_prop(buffer, "io_links_count",
 691                         dev->node_props.io_links_count);
 692         sysfs_show_32bit_prop(buffer, "cpu_core_id_base",
 693                         dev->node_props.cpu_core_id_base);
 694         sysfs_show_32bit_prop(buffer, "simd_id_base",
 695                         dev->node_props.simd_id_base);
 696         sysfs_show_32bit_prop(buffer, "max_waves_per_simd",
 697                         dev->node_props.max_waves_per_simd);
 698         sysfs_show_32bit_prop(buffer, "lds_size_in_kb",
 699                         dev->node_props.lds_size_in_kb);
 700         sysfs_show_32bit_prop(buffer, "gds_size_in_kb",
 701                         dev->node_props.gds_size_in_kb);
 702         sysfs_show_32bit_prop(buffer, "wave_front_size",
 703                         dev->node_props.wave_front_size);
 704         sysfs_show_32bit_prop(buffer, "array_count",
 705                         dev->node_props.array_count);
 706         sysfs_show_32bit_prop(buffer, "simd_arrays_per_engine",
 707                         dev->node_props.simd_arrays_per_engine);
 708         sysfs_show_32bit_prop(buffer, "cu_per_simd_array",
 709                         dev->node_props.cu_per_simd_array);
 710         sysfs_show_32bit_prop(buffer, "simd_per_cu",
 711                         dev->node_props.simd_per_cu);
 712         sysfs_show_32bit_prop(buffer, "max_slots_scratch_cu",
 713                         dev->node_props.max_slots_scratch_cu);
 714         sysfs_show_32bit_prop(buffer, "vendor_id",
 715                         dev->node_props.vendor_id);
 716         sysfs_show_32bit_prop(buffer, "device_id",
 717                         dev->node_props.device_id);
 718         sysfs_show_32bit_prop(buffer, "location_id",
 719                         dev->node_props.location_id);
 720
 721         if (dev->gpu) {
 722                 log_max_watch_addr =
 723                         __ilog2_u32(dev->gpu->device_info->num_of_watch_points);
 724
 725                 if (log_max_watch_addr) {
 726                         dev->node_props.capability |=
 727                                         HSA_CAP_WATCH_POINTS_SUPPORTED;
 728
 729                         dev->node_props.capability |=
 730                                 ((log_max_watch_addr <<
 731                                         HSA_CAP_WATCH_POINTS_TOTALBITS_SHIFT) &
 732                                 HSA_CAP_WATCH_POINTS_TOTALBITS_MASK);
 733                 }
 734
 735                 sysfs_show_32bit_prop(buffer, "max_engine_clk_fcompute",
 736                         dev->gpu->kfd2kgd->get_max_engine_clock_in_mhz(
 737                                         dev->gpu->kgd));
 738
 739                 sysfs_show_64bit_prop(buffer, "local_mem_size",
 740                                 (unsigned long long int) 0);
 741
 742                 sysfs_show_32bit_prop(buffer, "fw_version",
 743                         dev->gpu->kfd2kgd->get_fw_version(
 744                                                 dev->gpu->kgd,
 745                                                 KGD_ENGINE_MEC1));
 746                 sysfs_show_32bit_prop(buffer, "capability",
 747                                 dev->node_props.capability);
 748         }
 749
 750         return sysfs_show_32bit_prop(buffer, "max_engine_clk_ccompute",
 751                                         cpufreq_quick_get_max(0)/1000);
 752 }
 753
 754 static const struct sysfs_ops node_ops = {
 755         .show = node_show,
 756 };
 757
 758 static struct kobj_type node_type = {
 759         .release = kfd_topology_kobj_release,
 760         .sysfs_ops = &node_ops,
 761 };
 762
 763 static void kfd_remove_sysfs_file(struct kobject *kobj, struct attribute *attr)
 764 {
 765         sysfs_remove_file(kobj, attr);
 766         kobject_del(kobj);
 767         kobject_put(kobj);
 768 }
 769
 770 static void kfd_remove_sysfs_node_entry(struct kfd_topology_device *dev)
 771 {
 772         struct kfd_iolink_properties *iolink;
 773         struct kfd_cache_properties *cache;
 774         struct kfd_mem_properties *mem;
 775
 776         BUG_ON(!dev);
 777
 778         if (dev->kobj_iolink) {
 779                 list_for_each_entry(iolink, &dev->io_link_props, list)
 780                         if (iolink->kobj) {
 781                                 kfd_remove_sysfs_file(iolink->kobj,
 782                                                         &iolink->attr);
 783                                 iolink->kobj = NULL;
 784                         }
 785                 kobject_del(dev->kobj_iolink);
 786                 kobject_put(dev->kobj_iolink);
 787                 dev->kobj_iolink = NULL;
 788         }
 789
 790         if (dev->kobj_cache) {
 791                 list_for_each_entry(cache, &dev->cache_props, list)
 792                         if (cache->kobj) {
 793                                 kfd_remove_sysfs_file(cache->kobj,
 794                                                         &cache->attr);
 795                                 cache->kobj = NULL;
 796                         }
 797                 kobject_del(dev->kobj_cache);
 798                 kobject_put(dev->kobj_cache);
 799                 dev->kobj_cache = NULL;
 800         }
 801
 802         if (dev->kobj_mem) {
 803                 list_for_each_entry(mem, &dev->mem_props, list)
 804                         if (mem->kobj) {
 805                                 kfd_remove_sysfs_file(mem->kobj, &mem->attr);
 806                                 mem->kobj = NULL;
 807                         }
 808                 kobject_del(dev->kobj_mem);
 809                 kobject_put(dev->kobj_mem);
 810                 dev->kobj_mem = NULL;
 811         }
 812
 813         if (dev->kobj_node) {
 814                 sysfs_remove_file(dev->kobj_node, &dev->attr_gpuid);
 815                 sysfs_remove_file(dev->kobj_node, &dev->attr_name);
 816                 sysfs_remove_file(dev->kobj_node, &dev->attr_props);
 817                 kobject_del(dev->kobj_node);
 818                 kobject_put(dev->kobj_node);
 819                 dev->kobj_node = NULL;
 820         }
 821 }
 822
 823 static int kfd_build_sysfs_node_entry(struct kfd_topology_device *dev,
 824                 uint32_t id)
 825 {
 826         struct kfd_iolink_properties *iolink;
 827         struct kfd_cache_properties *cache;
 828         struct kfd_mem_properties *mem;
 829         int ret;
 830         uint32_t i;
 831
 832         BUG_ON(!dev);
 833
 834         /*
 835          * Creating the sysfs folders
 836          */
 837         BUG_ON(dev->kobj_node);
 838         dev->kobj_node = kfd_alloc_struct(dev->kobj_node);
 839         if (!dev->kobj_node)
 840                 return -ENOMEM;
 841
 842         ret = kobject_init_and_add(dev->kobj_node, &node_type,
 843                         sys_props.kobj_nodes, "%d", id);
 844         if (ret < 0) {
 845                 kobject_put(dev->kobj_node);
 846                 return ret;
 847         }
 848
 849         dev->kobj_mem = kobject_create_and_add("mem_banks", dev->kobj_node);
 850         if (!dev->kobj_mem)
 851                 return -ENOMEM;
 852
 853         dev->kobj_cache = kobject_create_and_add("caches", dev->kobj_node);
 854         if (!dev->kobj_cache)
 855                 return -ENOMEM;
 856
 857         dev->kobj_iolink = kobject_create_and_add("io_links", dev->kobj_node);
 858         if (!dev->kobj_iolink)
 859                 return -ENOMEM;
 860
 861         /*
 862          * Creating sysfs files for node properties
 863          */
 864         dev->attr_gpuid.name = "gpu_id";
 865         dev->attr_gpuid.mode = KFD_SYSFS_FILE_MODE;
 866         sysfs_attr_init(&dev->attr_gpuid);
 867         dev->attr_name.name = "name";
 868         dev->attr_name.mode = KFD_SYSFS_FILE_MODE;
 869         sysfs_attr_init(&dev->attr_name);
 870         dev->attr_props.name = "properties";
 871         dev->attr_props.mode = KFD_SYSFS_FILE_MODE;
 872         sysfs_attr_init(&dev->attr_props);
 873         ret = sysfs_create_file(dev->kobj_node, &dev->attr_gpuid);
 874         if (ret < 0)
 875                 return ret;
 876         ret = sysfs_create_file(dev->kobj_node, &dev->attr_name);
 877         if (ret < 0)
 878                 return ret;
 879         ret = sysfs_create_file(dev->kobj_node, &dev->attr_props);
 880         if (ret < 0)
 881                 return ret;
 882
 883         i = 0;
 884         list_for_each_entry(mem, &dev->mem_props, list) {
 885                 mem->kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL);
 886                 if (!mem->kobj)
 887                         return -ENOMEM;
 888                 ret = kobject_init_and_add(mem->kobj, &mem_type,
 889                                 dev->kobj_mem, "%d", i);
 890                 if (ret < 0) {
 891                         kobject_put(mem->kobj);
 892                         return ret;
 893                 }
 894
 895                 mem->attr.name = "properties";
 896                 mem->attr.mode = KFD_SYSFS_FILE_MODE;
 897                 sysfs_attr_init(&mem->attr);
 898                 ret = sysfs_create_file(mem->kobj, &mem->attr);
 899                 if (ret < 0)
 900                         return ret;
 901                 i++;
 902         }
 903
 904         i = 0;
 905         list_for_each_entry(cache, &dev->cache_props, list) {
 906                 cache->kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL);
 907                 if (!cache->kobj)
 908                         return -ENOMEM;
 909                 ret = kobject_init_and_add(cache->kobj, &cache_type,
 910                                 dev->kobj_cache, "%d", i);
 911                 if (ret < 0) {
 912                         kobject_put(cache->kobj);
 913                         return ret;
 914                 }
 915
 916                 cache->attr.name = "properties";
 917                 cache->attr.mode = KFD_SYSFS_FILE_MODE;
 918                 sysfs_attr_init(&cache->attr);
 919                 ret = sysfs_create_file(cache->kobj, &cache->attr);
 920                 if (ret < 0)
 921                         return ret;
 922                 i++;
 923         }
 924
 925         i = 0;
 926         list_for_each_entry(iolink, &dev->io_link_props, list) {
 927                 iolink->kobj = kzalloc(sizeof(struct kobject), GFP_KERNEL);
 928                 if (!iolink->kobj)
 929                         return -ENOMEM;
 930                 ret = kobject_init_and_add(iolink->kobj, &iolink_type,
 931                                 dev->kobj_iolink, "%d", i);
 932                 if (ret < 0) {
 933                         kobject_put(iolink->kobj);
 934                         return ret;
 935                 }
 936
 937                 iolink->attr.name = "properties";
 938                 iolink->attr.mode = KFD_SYSFS_FILE_MODE;
 939                 sysfs_attr_init(&iolink->attr);
 940                 ret = sysfs_create_file(iolink->kobj, &iolink->attr);
 941                 if (ret < 0)
 942                         return ret;
 943                 i++;
 944 }
 945
 946         return 0;
 947 }
 948
 949 static int kfd_build_sysfs_node_tree(void)
 950 {
 951         struct kfd_topology_device *dev;
 952         int ret;
 953         uint32_t i = 0;
 954
 955         list_for_each_entry(dev, &topology_device_list, list) {
 956                 ret = kfd_build_sysfs_node_entry(dev, i);
 957                 if (ret < 0)
 958                         return ret;
 959                 i++;
 960         }
 961
 962         return 0;
 963 }
 964
 965 static void kfd_remove_sysfs_node_tree(void)
 966 {
 967         struct kfd_topology_device *dev;
 968
 969         list_for_each_entry(dev, &topology_device_list, list)
 970                 kfd_remove_sysfs_node_entry(dev);
 971 }
 972
 973 static int kfd_topology_update_sysfs(void)
 974 {
 975         int ret;
 976
 977         pr_info("Creating topology SYSFS entries\n");
 978         if (sys_props.kobj_topology == NULL) {
 979                 sys_props.kobj_topology =
 980                                 kfd_alloc_struct(sys_props.kobj_topology);
 981                 if (!sys_props.kobj_topology)
 982                         return -ENOMEM;
 983
 984                 ret = kobject_init_and_add(sys_props.kobj_topology,
 985                                 &sysprops_type,  &kfd_device->kobj,
 986                                 "topology");
 987                 if (ret < 0) {
 988                         kobject_put(sys_props.kobj_topology);
 989                         return ret;
 990                 }
 991
 992                 sys_props.kobj_nodes = kobject_create_and_add("nodes",
 993                                 sys_props.kobj_topology);
 994                 if (!sys_props.kobj_nodes)
 995                         return -ENOMEM;
 996
 997                 sys_props.attr_genid.name = "generation_id";
 998                 sys_props.attr_genid.mode = KFD_SYSFS_FILE_MODE;
 999                 sysfs_attr_init(&sys_props.attr_genid);
1000                 ret = sysfs_create_file(sys_props.kobj_topology,
1001                                 &sys_props.attr_genid);
1002                 if (ret < 0)
1003                         return ret;
1004
1005                 sys_props.attr_props.name = "system_properties";
1006                 sys_props.attr_props.mode = KFD_SYSFS_FILE_MODE;
1007                 sysfs_attr_init(&sys_props.attr_props);
1008                 ret = sysfs_create_file(sys_props.kobj_topology,
1009                                 &sys_props.attr_props);
1010                 if (ret < 0)
1011                         return ret;
1012         }
1013
1014         kfd_remove_sysfs_node_tree();
1015
1016         return kfd_build_sysfs_node_tree();
1017 }
1018
1019 static void kfd_topology_release_sysfs(void)
1020 {
1021         kfd_remove_sysfs_node_tree();
1022         if (sys_props.kobj_topology) {
1023                 sysfs_remove_file(sys_props.kobj_topology,
1024                                 &sys_props.attr_genid);
1025                 sysfs_remove_file(sys_props.kobj_topology,
1026                                 &sys_props.attr_props);
1027                 if (sys_props.kobj_nodes) {
1028                         kobject_del(sys_props.kobj_nodes);
1029                         kobject_put(sys_props.kobj_nodes);
1030                         sys_props.kobj_nodes = NULL;
1031                 }
1032                 kobject_del(sys_props.kobj_topology);
1033                 kobject_put(sys_props.kobj_topology);
1034                 sys_props.kobj_topology = NULL;
1035         }
1036 }
1037
1038 int kfd_topology_init(void)
1039 {
1040         void *crat_image = NULL;
1041         size_t image_size = 0;
1042         int ret;
1043
1044         /*
1045          * Initialize the head for the topology device list
1046          */
1047         INIT_LIST_HEAD(&topology_device_list);
1048         init_rwsem(&topology_lock);
1049         topology_crat_parsed = 0;
1050
1051         memset(&sys_props, 0, sizeof(sys_props));
1052
1053         /*
1054          * Get the CRAT image from the ACPI
1055          */
1056         ret = kfd_topology_get_crat_acpi(crat_image, &image_size);
1057         if (ret == 0 && image_size > 0) {
1058                 pr_info("Found CRAT image with size=%zd\n", image_size);
1059                 crat_image = kmalloc(image_size, GFP_KERNEL);
1060                 if (!crat_image) {
1061                         ret = -ENOMEM;
1062                         pr_err("No memory for allocating CRAT image\n");
1063                         goto err;
1064                 }
1065                 ret = kfd_topology_get_crat_acpi(crat_image, &image_size);
1066
1067                 if (ret == 0) {
1068                         down_write(&topology_lock);
1069                         ret = kfd_parse_crat_table(crat_image);
1070                         if (ret == 0)
1071                                 ret = kfd_topology_update_sysfs();
1072                         up_write(&topology_lock);
1073                 } else {
1074                         pr_err("Couldn't get CRAT table size from ACPI\n");
1075                 }
1076                 kfree(crat_image);
1077         } else if (ret == -ENODATA) {
1078                 ret = 0;
1079         } else {
1080                 pr_err("Couldn't get CRAT table size from ACPI\n");
1081         }
1082
1083 err:
1084         pr_info("Finished initializing topology ret=%d\n", ret);
1085         return ret;
1086 }
1087
1088 void kfd_topology_shutdown(void)
1089 {
1090         kfd_topology_release_sysfs();
1091         kfd_release_live_view();
1092 }
1093
1094 static void kfd_debug_print_topology(void)
1095 {
1096         struct kfd_topology_device *dev;
1097         uint32_t i = 0;
1098
1099         pr_info("DEBUG PRINT OF TOPOLOGY:");
1100         list_for_each_entry(dev, &topology_device_list, list) {
1101                 pr_info("Node: %d\n", i);
1102                 pr_info("\tGPU assigned: %s\n", (dev->gpu ? "yes" : "no"));
1103                 pr_info("\tCPU count: %d\n", dev->node_props.cpu_cores_count);
1104                 pr_info("\tSIMD count: %d", dev->node_props.simd_count);
1105                 i++;
1106         }
1107 }
1108
1109 static uint32_t kfd_generate_gpu_id(struct kfd_dev *gpu)
1110 {
1111         uint32_t hashout;
1112         uint32_t buf[7];
1113         int i;
1114
1115         if (!gpu)
1116                 return 0;
1117
1118         buf[0] = gpu->pdev->devfn;
1119         buf[1] = gpu->pdev->subsystem_vendor;
1120         buf[2] = gpu->pdev->subsystem_device;
1121         buf[3] = gpu->pdev->device;
1122         buf[4] = gpu->pdev->bus->number;
1123         buf[5] = (uint32_t)(gpu->kfd2kgd->get_vmem_size(gpu->kgd)
1124                         & 0xffffffff);
1125         buf[6] = (uint32_t)(gpu->kfd2kgd->get_vmem_size(gpu->kgd) >> 32);
1126
1127         for (i = 0, hashout = 0; i < 7; i++)
1128                 hashout ^= hash_32(buf[i], KFD_GPU_ID_HASH_WIDTH);
1129
1130         return hashout;
1131 }
1132
1133 static struct kfd_topology_device *kfd_assign_gpu(struct kfd_dev *gpu)
1134 {
1135         struct kfd_topology_device *dev;
1136         struct kfd_topology_device *out_dev = NULL;
1137
1138         BUG_ON(!gpu);
1139
1140         list_for_each_entry(dev, &topology_device_list, list)
1141                 if (dev->gpu == NULL && dev->node_props.simd_count > 0) {
1142                         dev->gpu = gpu;
1143                         out_dev = dev;
1144                         break;
1145                 }
1146
1147         return out_dev;
1148 }
1149
1150 static void kfd_notify_gpu_change(uint32_t gpu_id, int arrival)
1151 {
1152         /*
1153          * TODO: Generate an event for thunk about the arrival/removal
1154          * of the GPU
1155          */
1156 }
1157
1158 int kfd_topology_add_device(struct kfd_dev *gpu)
1159 {
1160         uint32_t gpu_id;
1161         struct kfd_topology_device *dev;
1162         int res;
1163
1164         BUG_ON(!gpu);
1165
1166         gpu_id = kfd_generate_gpu_id(gpu);
1167
1168         pr_debug("kfd: Adding new GPU (ID: 0x%x) to topology\n", gpu_id);
1169
1170         down_write(&topology_lock);
1171         /*
1172          * Try to assign the GPU to existing topology device (generated from
1173          * CRAT table
1174          */
1175         dev = kfd_assign_gpu(gpu);
1176         if (!dev) {
1177                 pr_info("GPU was not found in the current topology. Extending.\n");
1178                 kfd_debug_print_topology();
1179                 dev = kfd_create_topology_device();
1180                 if (!dev) {
1181                         res = -ENOMEM;
1182                         goto err;
1183                 }
1184                 dev->gpu = gpu;
1185
1186                 /*
1187                  * TODO: Make a call to retrieve topology information from the
1188                  * GPU vBIOS
1189                  */
1190
1191                 /*
1192                  * Update the SYSFS tree, since we added another topology device
1193                  */
1194                 if (kfd_topology_update_sysfs() < 0)
1195                         kfd_topology_release_sysfs();
1196
1197         }
1198
1199         dev->gpu_id = gpu_id;
1200         gpu->id = gpu_id;
1201         dev->node_props.vendor_id = gpu->pdev->vendor;
1202         dev->node_props.device_id = gpu->pdev->device;
1203         dev->node_props.location_id = (gpu->pdev->bus->number << 24) +
1204                         (gpu->pdev->devfn & 0xffffff);
1205         /*
1206          * TODO: Retrieve max engine clock values from KGD
1207          */
1208
1209         if (dev->gpu->device_info->asic_family == CHIP_CARRIZO) {
1210                 dev->node_props.capability |= HSA_CAP_DOORBELL_PACKET_TYPE;
1211                 pr_info("amdkfd: adding doorbell packet type capability\n");
1212         }
1213
1214         res = 0;
1215
1216 err:
1217         up_write(&topology_lock);
1218
1219         if (res == 0)
1220                 kfd_notify_gpu_change(gpu_id, 1);
1221
1222         return res;
1223 }
1224
1225 int kfd_topology_remove_device(struct kfd_dev *gpu)
1226 {
1227         struct kfd_topology_device *dev;
1228         uint32_t gpu_id;
1229         int res = -ENODEV;
1230
1231         BUG_ON(!gpu);
1232
1233         down_write(&topology_lock);
1234
1235         list_for_each_entry(dev, &topology_device_list, list)
1236                 if (dev->gpu == gpu) {
1237                         gpu_id = dev->gpu_id;
1238                         kfd_remove_sysfs_node_entry(dev);
1239                         kfd_release_topology_device(dev);
1240                         res = 0;
1241                         if (kfd_topology_update_sysfs() < 0)
1242                                 kfd_topology_release_sysfs();
1243                         break;
1244                 }
1245
1246         up_write(&topology_lock);
1247
1248         if (res == 0)
1249                 kfd_notify_gpu_change(gpu_id, 0);
1250
1251         return res;
1252 }
1253
1254 /*
1255  * When idx is out of bounds, the function will return NULL
1256  */
1257 struct kfd_dev *kfd_topology_enum_kfd_devices(uint8_t idx)
1258 {
1259
1260         struct kfd_topology_device *top_dev;
1261         struct kfd_dev *device = NULL;
1262         uint8_t device_idx = 0;
1263
1264         down_read(&topology_lock);
1265
1266         list_for_each_entry(top_dev, &topology_device_list, list) {
1267                 if (device_idx == idx) {
1268                         device = top_dev->gpu;
1269                         break;
1270                 }
1271
1272                 device_idx++;
1273         }
1274
1275         up_read(&topology_lock);
1276
1277         return device;
1278
1279 }