drivers/misc/ocxl/core.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 // Copyright 2019 IBM Corp.
   3 #include <linux/idr.h>
   4 #include "ocxl_internal.h"
   5
   6 static struct ocxl_fn *ocxl_fn_get(struct ocxl_fn *fn)
   7 {
   8         return (get_device(&fn->dev) == NULL) ? NULL : fn;
   9 }
  10
  11 static void ocxl_fn_put(struct ocxl_fn *fn)
  12 {
  13         put_device(&fn->dev);
  14 }
  15
  16 static struct ocxl_afu *alloc_afu(struct ocxl_fn *fn)
  17 {
  18         struct ocxl_afu *afu;
  19
  20         afu = kzalloc(sizeof(struct ocxl_afu), GFP_KERNEL);
  21         if (!afu)
  22                 return NULL;
  23
  24         kref_init(&afu->kref);
  25         mutex_init(&afu->contexts_lock);
  26         mutex_init(&afu->afu_control_lock);
  27         idr_init(&afu->contexts_idr);
  28         afu->fn = fn;
  29         ocxl_fn_get(fn);
  30         return afu;
  31 }
  32
  33 static void free_afu(struct kref *kref)
  34 {
  35         struct ocxl_afu *afu = container_of(kref, struct ocxl_afu, kref);
  36
  37         idr_destroy(&afu->contexts_idr);
  38         ocxl_fn_put(afu->fn);
  39         kfree(afu);
  40 }
  41
  42 void ocxl_afu_get(struct ocxl_afu *afu)
  43 {
  44         kref_get(&afu->kref);
  45 }
  46 EXPORT_SYMBOL_GPL(ocxl_afu_get);
  47
  48 void ocxl_afu_put(struct ocxl_afu *afu)
  49 {
  50         kref_put(&afu->kref, free_afu);
  51 }
  52 EXPORT_SYMBOL_GPL(ocxl_afu_put);
  53
  54 static int assign_afu_actag(struct ocxl_afu *afu)
  55 {
  56         struct ocxl_fn *fn = afu->fn;
  57         int actag_count, actag_offset;
  58         struct pci_dev *pci_dev = to_pci_dev(fn->dev.parent);
  59
  60         /*
  61          * if there were not enough actags for the function, each afu
  62          * reduces its count as well
  63          */
  64         actag_count = afu->config.actag_supported *
  65                 fn->actag_enabled / fn->actag_supported;
  66         actag_offset = ocxl_actag_afu_alloc(fn, actag_count);
  67         if (actag_offset < 0) {
  68                 dev_err(&pci_dev->dev, "Can't allocate %d actags for AFU: %d\n",
  69                         actag_count, actag_offset);
  70                 return actag_offset;
  71         }
  72         afu->actag_base = fn->actag_base + actag_offset;
  73         afu->actag_enabled = actag_count;
  74
  75         ocxl_config_set_afu_actag(pci_dev, afu->config.dvsec_afu_control_pos,
  76                                 afu->actag_base, afu->actag_enabled);
  77         dev_dbg(&pci_dev->dev, "actag base=%d enabled=%d\n",
  78                 afu->actag_base, afu->actag_enabled);
  79         return 0;
  80 }
  81
  82 static void reclaim_afu_actag(struct ocxl_afu *afu)
  83 {
  84         struct ocxl_fn *fn = afu->fn;
  85         int start_offset, size;
  86
  87         start_offset = afu->actag_base - fn->actag_base;
  88         size = afu->actag_enabled;
  89         ocxl_actag_afu_free(afu->fn, start_offset, size);
  90 }
  91
  92 static int assign_afu_pasid(struct ocxl_afu *afu)
  93 {
  94         struct ocxl_fn *fn = afu->fn;
  95         int pasid_count, pasid_offset;
  96         struct pci_dev *pci_dev = to_pci_dev(fn->dev.parent);
  97
  98         /*
  99          * We only support the case where the function configuration
 100          * requested enough PASIDs to cover all AFUs.
 101          */
 102         pasid_count = 1 << afu->config.pasid_supported_log;
 103         pasid_offset = ocxl_pasid_afu_alloc(fn, pasid_count);
 104         if (pasid_offset < 0) {
 105                 dev_err(&pci_dev->dev, "Can't allocate %d PASIDs for AFU: %d\n",
 106                         pasid_count, pasid_offset);
 107                 return pasid_offset;
 108         }
 109         afu->pasid_base = fn->pasid_base + pasid_offset;
 110         afu->pasid_count = 0;
 111         afu->pasid_max = pasid_count;
 112
 113         ocxl_config_set_afu_pasid(pci_dev, afu->config.dvsec_afu_control_pos,
 114                                 afu->pasid_base,
 115                                 afu->config.pasid_supported_log);
 116         dev_dbg(&pci_dev->dev, "PASID base=%d, enabled=%d\n",
 117                 afu->pasid_base, pasid_count);
 118         return 0;
 119 }
 120
 121 static void reclaim_afu_pasid(struct ocxl_afu *afu)
 122 {
 123         struct ocxl_fn *fn = afu->fn;
 124         int start_offset, size;
 125
 126         start_offset = afu->pasid_base - fn->pasid_base;
 127         size = 1 << afu->config.pasid_supported_log;
 128         ocxl_pasid_afu_free(afu->fn, start_offset, size);
 129 }
 130
 131 static int reserve_fn_bar(struct ocxl_fn *fn, int bar)
 132 {
 133         struct pci_dev *dev = to_pci_dev(fn->dev.parent);
 134         int rc, idx;
 135
 136         if (bar != 0 && bar != 2 && bar != 4)
 137                 return -EINVAL;
 138
 139         idx = bar >> 1;
 140         if (fn->bar_used[idx]++ == 0) {
 141                 rc = pci_request_region(dev, bar, "ocxl");
 142                 if (rc)
 143                         return rc;
 144         }
 145         return 0;
 146 }
 147
 148 static void release_fn_bar(struct ocxl_fn *fn, int bar)
 149 {
 150         struct pci_dev *dev = to_pci_dev(fn->dev.parent);
 151         int idx;
 152
 153         if (bar != 0 && bar != 2 && bar != 4)
 154                 return;
 155
 156         idx = bar >> 1;
 157         if (--fn->bar_used[idx] == 0)
 158                 pci_release_region(dev, bar);
 159         WARN_ON(fn->bar_used[idx] < 0);
 160 }
 161
 162 static int map_mmio_areas(struct ocxl_afu *afu)
 163 {
 164         int rc;
 165         struct pci_dev *pci_dev = to_pci_dev(afu->fn->dev.parent);
 166
 167         rc = reserve_fn_bar(afu->fn, afu->config.global_mmio_bar);
 168         if (rc)
 169                 return rc;
 170
 171         rc = reserve_fn_bar(afu->fn, afu->config.pp_mmio_bar);
 172         if (rc) {
 173                 release_fn_bar(afu->fn, afu->config.global_mmio_bar);
 174                 return rc;
 175         }
 176
 177         afu->global_mmio_start =
 178                 pci_resource_start(pci_dev, afu->config.global_mmio_bar) +
 179                 afu->config.global_mmio_offset;
 180         afu->pp_mmio_start =
 181                 pci_resource_start(pci_dev, afu->config.pp_mmio_bar) +
 182                 afu->config.pp_mmio_offset;
 183
 184         afu->global_mmio_ptr = ioremap(afu->global_mmio_start,
 185                                 afu->config.global_mmio_size);
 186         if (!afu->global_mmio_ptr) {
 187                 release_fn_bar(afu->fn, afu->config.pp_mmio_bar);
 188                 release_fn_bar(afu->fn, afu->config.global_mmio_bar);
 189                 dev_err(&pci_dev->dev, "Error mapping global mmio area\n");
 190                 return -ENOMEM;
 191         }
 192
 193         /*
 194          * Leave an empty page between the per-process mmio area and
 195          * the AFU interrupt mappings
 196          */
 197         afu->irq_base_offset = afu->config.pp_mmio_stride + PAGE_SIZE;
 198         return 0;
 199 }
 200
 201 static void unmap_mmio_areas(struct ocxl_afu *afu)
 202 {
 203         if (afu->global_mmio_ptr) {
 204                 iounmap(afu->global_mmio_ptr);
 205                 afu->global_mmio_ptr = NULL;
 206         }
 207         afu->global_mmio_start = 0;
 208         afu->pp_mmio_start = 0;
 209         release_fn_bar(afu->fn, afu->config.pp_mmio_bar);
 210         release_fn_bar(afu->fn, afu->config.global_mmio_bar);
 211 }
 212
 213 static int configure_afu(struct ocxl_afu *afu, u8 afu_idx, struct pci_dev *dev)
 214 {
 215         int rc;
 216
 217         rc = ocxl_config_read_afu(dev, &afu->fn->config, &afu->config, afu_idx);
 218         if (rc)
 219                 return rc;
 220
 221         rc = assign_afu_actag(afu);
 222         if (rc)
 223                 return rc;
 224
 225         rc = assign_afu_pasid(afu);
 226         if (rc)
 227                 goto err_free_actag;
 228
 229         rc = map_mmio_areas(afu);
 230         if (rc)
 231                 goto err_free_pasid;
 232
 233         return 0;
 234
 235 err_free_pasid:
 236         reclaim_afu_pasid(afu);
 237 err_free_actag:
 238         reclaim_afu_actag(afu);
 239         return rc;
 240 }
 241
 242 static void deconfigure_afu(struct ocxl_afu *afu)
 243 {
 244         unmap_mmio_areas(afu);
 245         reclaim_afu_pasid(afu);
 246         reclaim_afu_actag(afu);
 247 }
 248
 249 static int activate_afu(struct pci_dev *dev, struct ocxl_afu *afu)
 250 {
 251         ocxl_config_set_afu_state(dev, afu->config.dvsec_afu_control_pos, 1);
 252
 253         return 0;
 254 }
 255
 256 static void deactivate_afu(struct ocxl_afu *afu)
 257 {
 258         struct pci_dev *dev = to_pci_dev(afu->fn->dev.parent);
 259
 260         ocxl_config_set_afu_state(dev, afu->config.dvsec_afu_control_pos, 0);
 261 }
 262
 263 static int init_afu(struct pci_dev *dev, struct ocxl_fn *fn, u8 afu_idx)
 264 {
 265         int rc;
 266         struct ocxl_afu *afu;
 267
 268         afu = alloc_afu(fn);
 269         if (!afu)
 270                 return -ENOMEM;
 271
 272         rc = configure_afu(afu, afu_idx, dev);
 273         if (rc) {
 274                 ocxl_afu_put(afu);
 275                 return rc;
 276         }
 277
 278         rc = activate_afu(dev, afu);
 279         if (rc) {
 280                 deconfigure_afu(afu);
 281                 ocxl_afu_put(afu);
 282                 return rc;
 283         }
 284
 285         list_add_tail(&afu->list, &fn->afu_list);
 286
 287         return 0;
 288 }
 289
 290 static void remove_afu(struct ocxl_afu *afu)
 291 {
 292         list_del(&afu->list);
 293         ocxl_context_detach_all(afu);
 294         deactivate_afu(afu);
 295         deconfigure_afu(afu);
 296         ocxl_afu_put(afu); // matches the implicit get in alloc_afu
 297 }
 298
 299 static struct ocxl_fn *alloc_function(void)
 300 {
 301         struct ocxl_fn *fn;
 302
 303         fn = kzalloc(sizeof(struct ocxl_fn), GFP_KERNEL);
 304         if (!fn)
 305                 return NULL;
 306
 307         INIT_LIST_HEAD(&fn->afu_list);
 308         INIT_LIST_HEAD(&fn->pasid_list);
 309         INIT_LIST_HEAD(&fn->actag_list);
 310
 311         return fn;
 312 }
 313
 314 static void free_function(struct ocxl_fn *fn)
 315 {
 316         WARN_ON(!list_empty(&fn->afu_list));
 317         WARN_ON(!list_empty(&fn->pasid_list));
 318         kfree(fn);
 319 }
 320
 321 static void free_function_dev(struct device *dev)
 322 {
 323         struct ocxl_fn *fn = container_of(dev, struct ocxl_fn, dev);
 324
 325         free_function(fn);
 326 }
 327
 328 static int set_function_device(struct ocxl_fn *fn, struct pci_dev *dev)
 329 {
 330         int rc;
 331
 332         fn->dev.parent = &dev->dev;
 333         fn->dev.release = free_function_dev;
 334         rc = dev_set_name(&fn->dev, "ocxlfn.%s", dev_name(&dev->dev));
 335         if (rc)
 336                 return rc;
 337         return 0;
 338 }
 339
 340 static int assign_function_actag(struct ocxl_fn *fn)
 341 {
 342         struct pci_dev *dev = to_pci_dev(fn->dev.parent);
 343         u16 base, enabled, supported;
 344         int rc;
 345
 346         rc = ocxl_config_get_actag_info(dev, &base, &enabled, &supported);
 347         if (rc)
 348                 return rc;
 349
 350         fn->actag_base = base;
 351         fn->actag_enabled = enabled;
 352         fn->actag_supported = supported;
 353
 354         ocxl_config_set_actag(dev, fn->config.dvsec_function_pos,
 355                         fn->actag_base, fn->actag_enabled);
 356         dev_dbg(&fn->dev, "actag range starting at %d, enabled %d\n",
 357                 fn->actag_base, fn->actag_enabled);
 358         return 0;
 359 }
 360
 361 static int set_function_pasid(struct ocxl_fn *fn)
 362 {
 363         struct pci_dev *dev = to_pci_dev(fn->dev.parent);
 364         int rc, desired_count, max_count;
 365
 366         /* A function may not require any PASID */
 367         if (fn->config.max_pasid_log < 0)
 368                 return 0;
 369
 370         rc = ocxl_config_get_pasid_info(dev, &max_count);
 371         if (rc)
 372                 return rc;
 373
 374         desired_count = 1 << fn->config.max_pasid_log;
 375
 376         if (desired_count > max_count) {
 377                 dev_err(&fn->dev,
 378                         "Function requires more PASIDs than is available (%d vs. %d)\n",
 379                         desired_count, max_count);
 380                 return -ENOSPC;
 381         }
 382
 383         fn->pasid_base = 0;
 384         return 0;
 385 }
 386
 387 static int configure_function(struct ocxl_fn *fn, struct pci_dev *dev)
 388 {
 389         int rc;
 390
 391         rc = pci_enable_device(dev);
 392         if (rc) {
 393                 dev_err(&dev->dev, "pci_enable_device failed: %d\n", rc);
 394                 return rc;
 395         }
 396
 397         /*
 398          * Once it has been confirmed to work on our hardware, we
 399          * should reset the function, to force the adapter to restart
 400          * from scratch.
 401          * A function reset would also reset all its AFUs.
 402          *
 403          * Some hints for implementation:
 404          *
 405          * - there's not status bit to know when the reset is done. We
 406          *   should try reading the config space to know when it's
 407          *   done.
 408          * - probably something like:
 409          *      Reset
 410          *      wait 100ms
 411          *      issue config read
 412          *      allow device up to 1 sec to return success on config
 413          *      read before declaring it broken
 414          *
 415          * Some shared logic on the card (CFG, TLX) won't be reset, so
 416          * there's no guarantee that it will be enough.
 417          */
 418         rc = ocxl_config_read_function(dev, &fn->config);
 419         if (rc)
 420                 return rc;
 421
 422         rc = set_function_device(fn, dev);
 423         if (rc)
 424                 return rc;
 425
 426         rc = assign_function_actag(fn);
 427         if (rc)
 428                 return rc;
 429
 430         rc = set_function_pasid(fn);
 431         if (rc)
 432                 return rc;
 433
 434         rc = ocxl_link_setup(dev, 0, &fn->link);
 435         if (rc)
 436                 return rc;
 437
 438         rc = ocxl_config_set_TL(dev, fn->config.dvsec_tl_pos);
 439         if (rc) {
 440                 ocxl_link_release(dev, fn->link);
 441                 return rc;
 442         }
 443         return 0;
 444 }
 445
 446 static void deconfigure_function(struct ocxl_fn *fn)
 447 {
 448         struct pci_dev *dev = to_pci_dev(fn->dev.parent);
 449
 450         ocxl_link_release(dev, fn->link);
 451         pci_disable_device(dev);
 452 }
 453
 454 static struct ocxl_fn *init_function(struct pci_dev *dev)
 455 {
 456         struct ocxl_fn *fn;
 457         int rc;
 458
 459         fn = alloc_function();
 460         if (!fn)
 461                 return ERR_PTR(-ENOMEM);
 462
 463         rc = configure_function(fn, dev);
 464         if (rc) {
 465                 free_function(fn);
 466                 return ERR_PTR(rc);
 467         }
 468
 469         rc = device_register(&fn->dev);
 470         if (rc) {
 471                 deconfigure_function(fn);
 472                 put_device(&fn->dev);
 473                 return ERR_PTR(rc);
 474         }
 475         return fn;
 476 }
 477
 478 // Device detection & initialisation
 479
 480 struct ocxl_fn *ocxl_function_open(struct pci_dev *dev)
 481 {
 482         int rc, afu_count = 0;
 483         u8 afu;
 484         struct ocxl_fn *fn;
 485
 486         if (!radix_enabled()) {
 487                 dev_err(&dev->dev, "Unsupported memory model (hash)\n");
 488                 return ERR_PTR(-ENODEV);
 489         }
 490
 491         fn = init_function(dev);
 492         if (IS_ERR(fn)) {
 493                 dev_err(&dev->dev, "function init failed: %li\n",
 494                         PTR_ERR(fn));
 495                 return fn;
 496         }
 497
 498         for (afu = 0; afu <= fn->config.max_afu_index; afu++) {
 499                 rc = ocxl_config_check_afu_index(dev, &fn->config, afu);
 500                 if (rc > 0) {
 501                         rc = init_afu(dev, fn, afu);
 502                         if (rc) {
 503                                 dev_err(&dev->dev,
 504                                         "Can't initialize AFU index %d\n", afu);
 505                                 continue;
 506                         }
 507                         afu_count++;
 508                 }
 509         }
 510         dev_info(&dev->dev, "%d AFU(s) configured\n", afu_count);
 511         return fn;
 512 }
 513 EXPORT_SYMBOL_GPL(ocxl_function_open);
 514
 515 struct list_head *ocxl_function_afu_list(struct ocxl_fn *fn)
 516 {
 517         return &fn->afu_list;
 518 }
 519 EXPORT_SYMBOL_GPL(ocxl_function_afu_list);
 520
 521 struct ocxl_afu *ocxl_function_fetch_afu(struct ocxl_fn *fn, u8 afu_idx)
 522 {
 523         struct ocxl_afu *afu;
 524
 525         list_for_each_entry(afu, &fn->afu_list, list) {
 526                 if (afu->config.idx == afu_idx)
 527                         return afu;
 528         }
 529
 530         return NULL;
 531 }
 532 EXPORT_SYMBOL_GPL(ocxl_function_fetch_afu);
 533
 534 const struct ocxl_fn_config *ocxl_function_config(struct ocxl_fn *fn)
 535 {
 536         return &fn->config;
 537 }
 538 EXPORT_SYMBOL_GPL(ocxl_function_config);
 539
 540 void ocxl_function_close(struct ocxl_fn *fn)
 541 {
 542         struct ocxl_afu *afu, *tmp;
 543
 544         list_for_each_entry_safe(afu, tmp, &fn->afu_list, list) {
 545                 remove_afu(afu);
 546         }
 547
 548         deconfigure_function(fn);
 549         device_unregister(&fn->dev);
 550 }
 551 EXPORT_SYMBOL_GPL(ocxl_function_close);
 552
 553 // AFU Metadata
 554
 555 struct ocxl_afu_config *ocxl_afu_config(struct ocxl_afu *afu)
 556 {
 557         return &afu->config;
 558 }
 559 EXPORT_SYMBOL_GPL(ocxl_afu_config);
 560
 561 void ocxl_afu_set_private(struct ocxl_afu *afu, void *private)
 562 {
 563         afu->private = private;
 564 }
 565 EXPORT_SYMBOL_GPL(ocxl_afu_set_private);
 566
 567 void *ocxl_afu_get_private(struct ocxl_afu *afu)
 568 {
 569         if (afu)
 570                 return afu->private;
 571
 572         return NULL;
 573 }
 574 EXPORT_SYMBOL_GPL(ocxl_afu_get_private);