kernel/irq/irqdomain.c

   1 #define pr_fmt(fmt)  "irq: " fmt
   2
   3 #include <linux/debugfs.h>
   4 #include <linux/hardirq.h>
   5 #include <linux/interrupt.h>
   6 #include <linux/irq.h>
   7 #include <linux/irqdesc.h>
   8 #include <linux/irqdomain.h>
   9 #include <linux/module.h>
  10 #include <linux/mutex.h>
  11 #include <linux/of.h>
  12 #include <linux/of_address.h>
  13 #include <linux/topology.h>
  14 #include <linux/seq_file.h>
  15 #include <linux/slab.h>
  16 #include <linux/smp.h>
  17 #include <linux/fs.h>
  18
  19 static LIST_HEAD(irq_domain_list);
  20 static DEFINE_MUTEX(irq_domain_mutex);
  21
  22 static DEFINE_MUTEX(revmap_trees_mutex);
  23 static struct irq_domain *irq_default_domain;
  24
  25 /**
  26  * irq_domain_alloc() - Allocate a new irq_domain data structure
  27  * @of_node: optional device-tree node of the interrupt controller
  28  * @revmap_type: type of reverse mapping to use
  29  * @ops: map/unmap domain callbacks
  30  * @host_data: Controller private data pointer
  31  *
  32  * Allocates and initialize and irq_domain structure.  Caller is expected to
  33  * register allocated irq_domain with irq_domain_register().  Returns pointer
  34  * to IRQ domain, or NULL on failure.
  35  */
  36 static struct irq_domain *irq_domain_alloc(struct device_node *of_node,
  37                                            unsigned int revmap_type,
  38                                            const struct irq_domain_ops *ops,
  39                                            void *host_data)
  40 {
  41         struct irq_domain *domain;
  42
  43         domain = kzalloc_node(sizeof(*domain), GFP_KERNEL,
  44                               of_node_to_nid(of_node));
  45         if (WARN_ON(!domain))
  46                 return NULL;
  47
  48         /* Fill structure */
  49         domain->revmap_type = revmap_type;
  50         domain->ops = ops;
  51         domain->host_data = host_data;
  52         domain->of_node = of_node_get(of_node);
  53
  54         return domain;
  55 }
  56
  57 static void irq_domain_free(struct irq_domain *domain)
  58 {
  59         of_node_put(domain->of_node);
  60         kfree(domain);
  61 }
  62
  63 static void irq_domain_add(struct irq_domain *domain)
  64 {
  65         mutex_lock(&irq_domain_mutex);
  66         list_add(&domain->link, &irq_domain_list);
  67         mutex_unlock(&irq_domain_mutex);
  68         pr_debug("Allocated domain of type %d @0x%p\n",
  69                  domain->revmap_type, domain);
  70 }
  71
  72 /**
  73  * irq_domain_remove() - Remove an irq domain.
  74  * @domain: domain to remove
  75  *
  76  * This routine is used to remove an irq domain. The caller must ensure
  77  * that all mappings within the domain have been disposed of prior to
  78  * use, depending on the revmap type.
  79  */
  80 void irq_domain_remove(struct irq_domain *domain)
  81 {
  82         mutex_lock(&irq_domain_mutex);
  83
  84         switch (domain->revmap_type) {
  85         case IRQ_DOMAIN_MAP_LEGACY:
  86                 /*
  87                  * Legacy domains don't manage their own irq_desc
  88                  * allocations, we expect the caller to handle irq_desc
  89                  * freeing on their own.
  90                  */
  91                 break;
  92         case IRQ_DOMAIN_MAP_TREE:
  93                 /*
  94                  * radix_tree_delete() takes care of destroying the root
  95                  * node when all entries are removed. Shout if there are
  96                  * any mappings left.
  97                  */
  98                 WARN_ON(domain->revmap_data.tree.height);
  99                 break;
 100         case IRQ_DOMAIN_MAP_LINEAR:
 101                 kfree(domain->revmap_data.linear.revmap);
 102                 domain->revmap_data.linear.size = 0;
 103                 break;
 104         case IRQ_DOMAIN_MAP_NOMAP:
 105                 break;
 106         }
 107
 108         list_del(&domain->link);
 109
 110         /*
 111          * If the going away domain is the default one, reset it.
 112          */
 113         if (unlikely(irq_default_domain == domain))
 114                 irq_set_default_host(NULL);
 115
 116         mutex_unlock(&irq_domain_mutex);
 117
 118         pr_debug("Removed domain of type %d @0x%p\n",
 119                  domain->revmap_type, domain);
 120
 121         irq_domain_free(domain);
 122 }
 123 EXPORT_SYMBOL_GPL(irq_domain_remove);
 124
 125 static unsigned int irq_domain_legacy_revmap(struct irq_domain *domain,
 126                                              irq_hw_number_t hwirq)
 127 {
 128         irq_hw_number_t first_hwirq = domain->revmap_data.legacy.first_hwirq;
 129         int size = domain->revmap_data.legacy.size;
 130
 131         if (WARN_ON(hwirq < first_hwirq || hwirq >= first_hwirq + size))
 132                 return 0;
 133         return hwirq - first_hwirq + domain->revmap_data.legacy.first_irq;
 134 }
 135
 136 /**
 137  * irq_domain_add_simple() - Allocate and register a simple irq_domain.
 138  * @of_node: pointer to interrupt controller's device tree node.
 139  * @size: total number of irqs in mapping
 140  * @first_irq: first number of irq block assigned to the domain,
 141  *      pass zero to assign irqs on-the-fly. This will result in a
 142  *      linear IRQ domain so it is important to use irq_create_mapping()
 143  *      for each used IRQ, especially when SPARSE_IRQ is enabled.
 144  * @ops: map/unmap domain callbacks
 145  * @host_data: Controller private data pointer
 146  *
 147  * Allocates a legacy irq_domain if irq_base is positive or a linear
 148  * domain otherwise. For the legacy domain, IRQ descriptors will also
 149  * be allocated.
 150  *
 151  * This is intended to implement the expected behaviour for most
 152  * interrupt controllers which is that a linear mapping should
 153  * normally be used unless the system requires a legacy mapping in
 154  * order to support supplying interrupt numbers during non-DT
 155  * registration of devices.
 156  */
 157 struct irq_domain *irq_domain_add_simple(struct device_node *of_node,
 158                                          unsigned int size,
 159                                          unsigned int first_irq,
 160                                          const struct irq_domain_ops *ops,
 161                                          void *host_data)
 162 {
 163         if (first_irq > 0) {
 164                 int irq_base;
 165
 166                 if (IS_ENABLED(CONFIG_SPARSE_IRQ)) {
 167                         /*
 168                          * Set the descriptor allocator to search for a
 169                          * 1-to-1 mapping, such as irq_alloc_desc_at().
 170                          * Use of_node_to_nid() which is defined to
 171                          * numa_node_id() on platforms that have no custom
 172                          * implementation.
 173                          */
 174                         irq_base = irq_alloc_descs(first_irq, first_irq, size,
 175                                                    of_node_to_nid(of_node));
 176                         if (irq_base < 0) {
 177                                 pr_info("Cannot allocate irq_descs @ IRQ%d, assuming pre-allocated\n",
 178                                         first_irq);
 179                                 irq_base = first_irq;
 180                         }
 181                 } else
 182                         irq_base = first_irq;
 183
 184                 return irq_domain_add_legacy(of_node, size, irq_base, 0,
 185                                              ops, host_data);
 186         }
 187
 188         /* A linear domain is the default */
 189         return irq_domain_add_linear(of_node, size, ops, host_data);
 190 }
 191 EXPORT_SYMBOL_GPL(irq_domain_add_simple);
 192
 193 /**
 194  * irq_domain_add_legacy() - Allocate and register a legacy revmap irq_domain.
 195  * @of_node: pointer to interrupt controller's device tree node.
 196  * @size: total number of irqs in legacy mapping
 197  * @first_irq: first number of irq block assigned to the domain
 198  * @first_hwirq: first hwirq number to use for the translation. Should normally
 199  *               be '0', but a positive integer can be used if the effective
 200  *               hwirqs numbering does not begin at zero.
 201  * @ops: map/unmap domain callbacks
 202  * @host_data: Controller private data pointer
 203  *
 204  * Note: the map() callback will be called before this function returns
 205  * for all legacy interrupts except 0 (which is always the invalid irq for
 206  * a legacy controller).
 207  */
 208 struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
 209                                          unsigned int size,
 210                                          unsigned int first_irq,
 211                                          irq_hw_number_t first_hwirq,
 212                                          const struct irq_domain_ops *ops,
 213                                          void *host_data)
 214 {
 215         struct irq_domain *domain;
 216         unsigned int i;
 217
 218         domain = irq_domain_alloc(of_node, IRQ_DOMAIN_MAP_LEGACY, ops, host_data);
 219         if (!domain)
 220                 return NULL;
 221
 222         domain->revmap_data.legacy.first_irq = first_irq;
 223         domain->revmap_data.legacy.first_hwirq = first_hwirq;
 224         domain->revmap_data.legacy.size = size;
 225
 226         mutex_lock(&irq_domain_mutex);
 227         /* Verify that all the irqs are available */
 228         for (i = 0; i < size; i++) {
 229                 int irq = first_irq + i;
 230                 struct irq_data *irq_data = irq_get_irq_data(irq);
 231
 232                 if (WARN_ON(!irq_data || irq_data->domain)) {
 233                         mutex_unlock(&irq_domain_mutex);
 234                         irq_domain_free(domain);
 235                         return NULL;
 236                 }
 237         }
 238
 239         /* Claim all of the irqs before registering a legacy domain */
 240         for (i = 0; i < size; i++) {
 241                 struct irq_data *irq_data = irq_get_irq_data(first_irq + i);
 242                 irq_data->hwirq = first_hwirq + i;
 243                 irq_data->domain = domain;
 244         }
 245         mutex_unlock(&irq_domain_mutex);
 246
 247         for (i = 0; i < size; i++) {
 248                 int irq = first_irq + i;
 249                 int hwirq = first_hwirq + i;
 250
 251                 /* IRQ0 gets ignored */
 252                 if (!irq)
 253                         continue;
 254
 255                 /* Legacy flags are left to default at this point,
 256                  * one can then use irq_create_mapping() to
 257                  * explicitly change them
 258                  */
 259                 if (ops->map)
 260                         ops->map(domain, irq, hwirq);
 261
 262                 /* Clear norequest flags */
 263                 irq_clear_status_flags(irq, IRQ_NOREQUEST);
 264         }
 265
 266         irq_domain_add(domain);
 267         return domain;
 268 }
 269 EXPORT_SYMBOL_GPL(irq_domain_add_legacy);
 270
 271 /**
 272  * irq_domain_add_linear() - Allocate and register a linear revmap irq_domain.
 273  * @of_node: pointer to interrupt controller's device tree node.
 274  * @size: Number of interrupts in the domain.
 275  * @ops: map/unmap domain callbacks
 276  * @host_data: Controller private data pointer
 277  */
 278 struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
 279                                          unsigned int size,
 280                                          const struct irq_domain_ops *ops,
 281                                          void *host_data)
 282 {
 283         struct irq_domain *domain;
 284         unsigned int *revmap;
 285
 286         revmap = kzalloc_node(sizeof(*revmap) * size, GFP_KERNEL,
 287                               of_node_to_nid(of_node));
 288         if (WARN_ON(!revmap))
 289                 return NULL;
 290
 291         domain = irq_domain_alloc(of_node, IRQ_DOMAIN_MAP_LINEAR, ops, host_data);
 292         if (!domain) {
 293                 kfree(revmap);
 294                 return NULL;
 295         }
 296         domain->revmap_data.linear.size = size;
 297         domain->revmap_data.linear.revmap = revmap;
 298         irq_domain_add(domain);
 299         return domain;
 300 }
 301 EXPORT_SYMBOL_GPL(irq_domain_add_linear);
 302
 303 struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
 304                                          unsigned int max_irq,
 305                                          const struct irq_domain_ops *ops,
 306                                          void *host_data)
 307 {
 308         struct irq_domain *domain = irq_domain_alloc(of_node,
 309                                         IRQ_DOMAIN_MAP_NOMAP, ops, host_data);
 310         if (domain) {
 311                 domain->revmap_data.nomap.max_irq = max_irq ? max_irq : ~0;
 312                 irq_domain_add(domain);
 313         }
 314         return domain;
 315 }
 316 EXPORT_SYMBOL_GPL(irq_domain_add_nomap);
 317
 318 /**
 319  * irq_domain_add_tree()
 320  * @of_node: pointer to interrupt controller's device tree node.
 321  * @ops: map/unmap domain callbacks
 322  *
 323  * Note: The radix tree will be allocated later during boot automatically
 324  * (the reverse mapping will use the slow path until that happens).
 325  */
 326 struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
 327                                          const struct irq_domain_ops *ops,
 328                                          void *host_data)
 329 {
 330         struct irq_domain *domain = irq_domain_alloc(of_node,
 331                                         IRQ_DOMAIN_MAP_TREE, ops, host_data);
 332         if (domain) {
 333                 INIT_RADIX_TREE(&domain->revmap_data.tree, GFP_KERNEL);
 334                 irq_domain_add(domain);
 335         }
 336         return domain;
 337 }
 338 EXPORT_SYMBOL_GPL(irq_domain_add_tree);
 339
 340 /**
 341  * irq_find_host() - Locates a domain for a given device node
 342  * @node: device-tree node of the interrupt controller
 343  */
 344 struct irq_domain *irq_find_host(struct device_node *node)
 345 {
 346         struct irq_domain *h, *found = NULL;
 347         int rc;
 348
 349         /* We might want to match the legacy controller last since
 350          * it might potentially be set to match all interrupts in
 351          * the absence of a device node. This isn't a problem so far
 352          * yet though...
 353          */
 354         mutex_lock(&irq_domain_mutex);
 355         list_for_each_entry(h, &irq_domain_list, link) {
 356                 if (h->ops->match)
 357                         rc = h->ops->match(h, node);
 358                 else
 359                         rc = (h->of_node != NULL) && (h->of_node == node);
 360
 361                 if (rc) {
 362                         found = h;
 363                         break;
 364                 }
 365         }
 366         mutex_unlock(&irq_domain_mutex);
 367         return found;
 368 }
 369 EXPORT_SYMBOL_GPL(irq_find_host);
 370
 371 /**
 372  * irq_set_default_host() - Set a "default" irq domain
 373  * @domain: default domain pointer
 374  *
 375  * For convenience, it's possible to set a "default" domain that will be used
 376  * whenever NULL is passed to irq_create_mapping(). It makes life easier for
 377  * platforms that want to manipulate a few hard coded interrupt numbers that
 378  * aren't properly represented in the device-tree.
 379  */
 380 void irq_set_default_host(struct irq_domain *domain)
 381 {
 382         pr_debug("Default domain set to @0x%p\n", domain);
 383
 384         irq_default_domain = domain;
 385 }
 386 EXPORT_SYMBOL_GPL(irq_set_default_host);
 387
 388 static void irq_domain_disassociate_many(struct irq_domain *domain,
 389                                          unsigned int irq_base, int count)
 390 {
 391         /*
 392          * disassociate in reverse order;
 393          * not strictly necessary, but nice for unwinding
 394          */
 395         while (count--) {
 396                 int irq = irq_base + count;
 397                 struct irq_data *irq_data = irq_get_irq_data(irq);
 398                 irq_hw_number_t hwirq;
 399
 400                 if (WARN_ON(!irq_data || irq_data->domain != domain))
 401                         continue;
 402
 403                 hwirq = irq_data->hwirq;
 404                 irq_set_status_flags(irq, IRQ_NOREQUEST);
 405
 406                 /* remove chip and handler */
 407                 irq_set_chip_and_handler(irq, NULL, NULL);
 408
 409                 /* Make sure it's completed */
 410                 synchronize_irq(irq);
 411
 412                 /* Tell the PIC about it */
 413                 if (domain->ops->unmap)
 414                         domain->ops->unmap(domain, irq);
 415                 smp_mb();
 416
 417                 irq_data->domain = NULL;
 418                 irq_data->hwirq = 0;
 419
 420                 /* Clear reverse map */
 421                 switch(domain->revmap_type) {
 422                 case IRQ_DOMAIN_MAP_LINEAR:
 423                         if (hwirq < domain->revmap_data.linear.size)
 424                                 domain->revmap_data.linear.revmap[hwirq] = 0;
 425                         break;
 426                 case IRQ_DOMAIN_MAP_TREE:
 427                         mutex_lock(&revmap_trees_mutex);
 428                         radix_tree_delete(&domain->revmap_data.tree, hwirq);
 429                         mutex_unlock(&revmap_trees_mutex);
 430                         break;
 431                 }
 432         }
 433 }
 434
 435 int irq_domain_associate_many(struct irq_domain *domain, unsigned int irq_base,
 436                               irq_hw_number_t hwirq_base, int count)
 437 {
 438         unsigned int virq = irq_base;
 439         irq_hw_number_t hwirq = hwirq_base;
 440         int i, ret;
 441
 442         pr_debug("%s(%s, irqbase=%i, hwbase=%i, count=%i)\n", __func__,
 443                 of_node_full_name(domain->of_node), irq_base, (int)hwirq_base, count);
 444
 445         for (i = 0; i < count; i++) {
 446                 struct irq_data *irq_data = irq_get_irq_data(virq + i);
 447
 448                 if (WARN(!irq_data, "error: irq_desc not allocated; "
 449                          "irq=%i hwirq=0x%x\n", virq + i, (int)hwirq + i))
 450                         return -EINVAL;
 451                 if (WARN(irq_data->domain, "error: irq_desc already associated; "
 452                          "irq=%i hwirq=0x%x\n", virq + i, (int)hwirq + i))
 453                         return -EINVAL;
 454         };
 455
 456         for (i = 0; i < count; i++, virq++, hwirq++) {
 457                 struct irq_data *irq_data = irq_get_irq_data(virq);
 458
 459                 irq_data->hwirq = hwirq;
 460                 irq_data->domain = domain;
 461                 if (domain->ops->map) {
 462                         ret = domain->ops->map(domain, virq, hwirq);
 463                         if (ret != 0) {
 464                                 /*
 465                                  * If map() returns -EPERM, this interrupt is protected
 466                                  * by the firmware or some other service and shall not
 467                                  * be mapped.
 468                                  *
 469                                  * Since on some platforms we blindly try to map everything
 470                                  * we end up with a log full of backtraces.
 471                                  *
 472                                  * So instead, we silently fail on -EPERM, it is the
 473                                  * responsibility of the PIC driver to display a relevant
 474                                  * message if needed.
 475                                  */
 476                                 if (ret != -EPERM) {
 477                                         pr_err("irq-%i==>hwirq-0x%lx mapping failed: %d\n",
 478                                                virq, hwirq, ret);
 479                                         WARN_ON(1);
 480                                 }
 481                                 irq_data->domain = NULL;
 482                                 irq_data->hwirq = 0;
 483                                 goto err_unmap;
 484                         }
 485                 }
 486
 487                 switch (domain->revmap_type) {
 488                 case IRQ_DOMAIN_MAP_LINEAR:
 489                         if (hwirq < domain->revmap_data.linear.size)
 490                                 domain->revmap_data.linear.revmap[hwirq] = virq;
 491                         break;
 492                 case IRQ_DOMAIN_MAP_TREE:
 493                         mutex_lock(&revmap_trees_mutex);
 494                         radix_tree_insert(&domain->revmap_data.tree, hwirq, irq_data);
 495                         mutex_unlock(&revmap_trees_mutex);
 496                         break;
 497                 }
 498
 499                 irq_clear_status_flags(virq, IRQ_NOREQUEST);
 500         }
 501
 502         return 0;
 503
 504  err_unmap:
 505         irq_domain_disassociate_many(domain, irq_base, i);
 506         return -EINVAL;
 507 }
 508 EXPORT_SYMBOL_GPL(irq_domain_associate_many);
 509
 510 /**
 511  * irq_create_direct_mapping() - Allocate an irq for direct mapping
 512  * @domain: domain to allocate the irq for or NULL for default domain
 513  *
 514  * This routine is used for irq controllers which can choose the hardware
 515  * interrupt numbers they generate. In such a case it's simplest to use
 516  * the linux irq as the hardware interrupt number.
 517  */
 518 unsigned int irq_create_direct_mapping(struct irq_domain *domain)
 519 {
 520         unsigned int virq;
 521
 522         if (domain == NULL)
 523                 domain = irq_default_domain;
 524
 525         if (WARN_ON(!domain || domain->revmap_type != IRQ_DOMAIN_MAP_NOMAP))
 526                 return 0;
 527
 528         virq = irq_alloc_desc_from(1, of_node_to_nid(domain->of_node));
 529         if (!virq) {
 530                 pr_debug("create_direct virq allocation failed\n");
 531                 return 0;
 532         }
 533         if (virq >= domain->revmap_data.nomap.max_irq) {
 534                 pr_err("ERROR: no free irqs available below %i maximum\n",
 535                         domain->revmap_data.nomap.max_irq);
 536                 irq_free_desc(virq);
 537                 return 0;
 538         }
 539         pr_debug("create_direct obtained virq %d\n", virq);
 540
 541         if (irq_domain_associate(domain, virq, virq)) {
 542                 irq_free_desc(virq);
 543                 return 0;
 544         }
 545
 546         return virq;
 547 }
 548 EXPORT_SYMBOL_GPL(irq_create_direct_mapping);
 549
 550 /**
 551  * irq_create_mapping() - Map a hardware interrupt into linux irq space
 552  * @domain: domain owning this hardware interrupt or NULL for default domain
 553  * @hwirq: hardware irq number in that domain space
 554  *
 555  * Only one mapping per hardware interrupt is permitted. Returns a linux
 556  * irq number.
 557  * If the sense/trigger is to be specified, set_irq_type() should be called
 558  * on the number returned from that call.
 559  */
 560 unsigned int irq_create_mapping(struct irq_domain *domain,
 561                                 irq_hw_number_t hwirq)
 562 {
 563         unsigned int hint;
 564         int virq;
 565
 566         pr_debug("irq_create_mapping(0x%p, 0x%lx)\n", domain, hwirq);
 567
 568         /* Look for default domain if nececssary */
 569         if (domain == NULL)
 570                 domain = irq_default_domain;
 571         if (domain == NULL) {
 572                 pr_warning("irq_create_mapping called for"
 573                            " NULL domain, hwirq=%lx\n", hwirq);
 574                 WARN_ON(1);
 575                 return 0;
 576         }
 577         pr_debug("-> using domain @%p\n", domain);
 578
 579         /* Check if mapping already exists */
 580         virq = irq_find_mapping(domain, hwirq);
 581         if (virq) {
 582                 pr_debug("-> existing mapping on virq %d\n", virq);
 583                 return virq;
 584         }
 585
 586         /* Get a virtual interrupt number */
 587         if (domain->revmap_type == IRQ_DOMAIN_MAP_LEGACY)
 588                 return irq_domain_legacy_revmap(domain, hwirq);
 589
 590         /* Allocate a virtual interrupt number */
 591         hint = hwirq % nr_irqs;
 592         if (hint == 0)
 593                 hint++;
 594         virq = irq_alloc_desc_from(hint, of_node_to_nid(domain->of_node));
 595         if (virq <= 0)
 596                 virq = irq_alloc_desc_from(1, of_node_to_nid(domain->of_node));
 597         if (virq <= 0) {
 598                 pr_debug("-> virq allocation failed\n");
 599                 return 0;
 600         }
 601
 602         if (irq_domain_associate(domain, virq, hwirq)) {
 603                 irq_free_desc(virq);
 604                 return 0;
 605         }
 606
 607         pr_debug("irq %lu on domain %s mapped to virtual irq %u\n",
 608                 hwirq, of_node_full_name(domain->of_node), virq);
 609
 610         return virq;
 611 }
 612 EXPORT_SYMBOL_GPL(irq_create_mapping);
 613
 614 /**
 615  * irq_create_strict_mappings() - Map a range of hw irqs to fixed linux irqs
 616  * @domain: domain owning the interrupt range
 617  * @irq_base: beginning of linux IRQ range
 618  * @hwirq_base: beginning of hardware IRQ range
 619  * @count: Number of interrupts to map
 620  *
 621  * This routine is used for allocating and mapping a range of hardware
 622  * irqs to linux irqs where the linux irq numbers are at pre-defined
 623  * locations. For use by controllers that already have static mappings
 624  * to insert in to the domain.
 625  *
 626  * Non-linear users can use irq_create_identity_mapping() for IRQ-at-a-time
 627  * domain insertion.
 628  *
 629  * 0 is returned upon success, while any failure to establish a static
 630  * mapping is treated as an error.
 631  */
 632 int irq_create_strict_mappings(struct irq_domain *domain, unsigned int irq_base,
 633                                irq_hw_number_t hwirq_base, int count)
 634 {
 635         int ret;
 636
 637         ret = irq_alloc_descs(irq_base, irq_base, count,
 638                               of_node_to_nid(domain->of_node));
 639         if (unlikely(ret < 0))
 640                 return ret;
 641
 642         ret = irq_domain_associate_many(domain, irq_base, hwirq_base, count);
 643         if (unlikely(ret < 0)) {
 644                 irq_free_descs(irq_base, count);
 645                 return ret;
 646         }
 647
 648         return 0;
 649 }
 650 EXPORT_SYMBOL_GPL(irq_create_strict_mappings);
 651
 652 unsigned int irq_create_of_mapping(struct device_node *controller,
 653                                    const u32 *intspec, unsigned int intsize)
 654 {
 655         struct irq_domain *domain;
 656         irq_hw_number_t hwirq;
 657         unsigned int type = IRQ_TYPE_NONE;
 658         unsigned int virq;
 659
 660         domain = controller ? irq_find_host(controller) : irq_default_domain;
 661         if (!domain) {
 662 #ifdef CONFIG_MIPS
 663                 /*
 664                  * Workaround to avoid breaking interrupt controller drivers
 665                  * that don't yet register an irq_domain.  This is temporary
 666                  * code. ~~~gcl, Feb 24, 2012
 667                  *
 668                  * Scheduled for removal in Linux v3.6.  That should be enough
 669                  * time.
 670                  */
 671                 if (intsize > 0)
 672                         return intspec[0];
 673 #endif
 674                 pr_warning("no irq domain found for %s !\n",
 675                            of_node_full_name(controller));
 676                 return 0;
 677         }
 678
 679         /* If domain has no translation, then we assume interrupt line */
 680         if (domain->ops->xlate == NULL)
 681                 hwirq = intspec[0];
 682         else {
 683                 if (domain->ops->xlate(domain, controller, intspec, intsize,
 684                                      &hwirq, &type))
 685                         return 0;
 686         }
 687
 688         /* Create mapping */
 689         virq = irq_create_mapping(domain, hwirq);
 690         if (!virq)
 691                 return virq;
 692
 693         /* Set type if specified and different than the current one */
 694         if (type != IRQ_TYPE_NONE &&
 695             type != irq_get_trigger_type(virq))
 696                 irq_set_irq_type(virq, type);
 697         return virq;
 698 }
 699 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
 700
 701 /**
 702  * irq_dispose_mapping() - Unmap an interrupt
 703  * @virq: linux irq number of the interrupt to unmap
 704  */
 705 void irq_dispose_mapping(unsigned int virq)
 706 {
 707         struct irq_data *irq_data = irq_get_irq_data(virq);
 708         struct irq_domain *domain;
 709
 710         if (!virq || !irq_data)
 711                 return;
 712
 713         domain = irq_data->domain;
 714         if (WARN_ON(domain == NULL))
 715                 return;
 716
 717         /* Never unmap legacy interrupts */
 718         if (domain->revmap_type == IRQ_DOMAIN_MAP_LEGACY)
 719                 return;
 720
 721         irq_domain_disassociate_many(domain, virq, 1);
 722         irq_free_desc(virq);
 723 }
 724 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
 725
 726 /**
 727  * irq_find_mapping() - Find a linux irq from an hw irq number.
 728  * @domain: domain owning this hardware interrupt
 729  * @hwirq: hardware irq number in that domain space
 730  */
 731 unsigned int irq_find_mapping(struct irq_domain *domain,
 732                               irq_hw_number_t hwirq)
 733 {
 734         struct irq_data *data;
 735
 736         /* Look for default domain if nececssary */
 737         if (domain == NULL)
 738                 domain = irq_default_domain;
 739         if (domain == NULL)
 740                 return 0;
 741
 742         switch (domain->revmap_type) {
 743         case IRQ_DOMAIN_MAP_LEGACY:
 744                 return irq_domain_legacy_revmap(domain, hwirq);
 745         case IRQ_DOMAIN_MAP_LINEAR:
 746                 return irq_linear_revmap(domain, hwirq);
 747         case IRQ_DOMAIN_MAP_TREE:
 748                 rcu_read_lock();
 749                 data = radix_tree_lookup(&domain->revmap_data.tree, hwirq);
 750                 rcu_read_unlock();
 751                 if (data)
 752                         return data->irq;
 753                 break;
 754         case IRQ_DOMAIN_MAP_NOMAP:
 755                 data = irq_get_irq_data(hwirq);
 756                 if (data && (data->domain == domain) && (data->hwirq == hwirq))
 757                         return hwirq;
 758                 break;
 759         }
 760
 761         return 0;
 762 }
 763 EXPORT_SYMBOL_GPL(irq_find_mapping);
 764
 765 /**
 766  * irq_linear_revmap() - Find a linux irq from a hw irq number.
 767  * @domain: domain owning this hardware interrupt
 768  * @hwirq: hardware irq number in that domain space
 769  *
 770  * This is a fast path that can be called directly by irq controller code to
 771  * save a handful of instructions.
 772  */
 773 unsigned int irq_linear_revmap(struct irq_domain *domain,
 774                                irq_hw_number_t hwirq)
 775 {
 776         BUG_ON(domain->revmap_type != IRQ_DOMAIN_MAP_LINEAR);
 777
 778         /* Check revmap bounds; complain if exceeded */
 779         if (WARN_ON(hwirq >= domain->revmap_data.linear.size))
 780                 return 0;
 781
 782         return domain->revmap_data.linear.revmap[hwirq];
 783 }
 784 EXPORT_SYMBOL_GPL(irq_linear_revmap);
 785
 786 #ifdef CONFIG_IRQ_DOMAIN_DEBUG
 787 static int virq_debug_show(struct seq_file *m, void *private)
 788 {
 789         unsigned long flags;
 790         struct irq_desc *desc;
 791         const char *p;
 792         static const char none[] = "none";
 793         void *data;
 794         int i;
 795
 796         seq_printf(m, "%-5s  %-7s  %-15s  %-*s  %s\n", "irq", "hwirq",
 797                       "chip name", (int)(2 * sizeof(void *) + 2), "chip data",
 798                       "domain name");
 799
 800         for (i = 1; i < nr_irqs; i++) {
 801                 desc = irq_to_desc(i);
 802                 if (!desc)
 803                         continue;
 804
 805                 raw_spin_lock_irqsave(&desc->lock, flags);
 806
 807                 if (desc->action && desc->action->handler) {
 808                         struct irq_chip *chip;
 809
 810                         seq_printf(m, "%5d  ", i);
 811                         seq_printf(m, "0x%05lx  ", desc->irq_data.hwirq);
 812
 813                         chip = irq_desc_get_chip(desc);
 814                         if (chip && chip->name)
 815                                 p = chip->name;
 816                         else
 817                                 p = none;
 818                         seq_printf(m, "%-15s  ", p);
 819
 820                         data = irq_desc_get_chip_data(desc);
 821                         seq_printf(m, data ? "0x%p  " : "  %p  ", data);
 822
 823                         if (desc->irq_data.domain)
 824                                 p = of_node_full_name(desc->irq_data.domain->of_node);
 825                         else
 826                                 p = none;
 827                         seq_printf(m, "%s\n", p);
 828                 }
 829
 830                 raw_spin_unlock_irqrestore(&desc->lock, flags);
 831         }
 832
 833         return 0;
 834 }
 835
 836 static int virq_debug_open(struct inode *inode, struct file *file)
 837 {
 838         return single_open(file, virq_debug_show, inode->i_private);
 839 }
 840
 841 static const struct file_operations virq_debug_fops = {
 842         .open = virq_debug_open,
 843         .read = seq_read,
 844         .llseek = seq_lseek,
 845         .release = single_release,
 846 };
 847
 848 static int __init irq_debugfs_init(void)
 849 {
 850         if (debugfs_create_file("irq_domain_mapping", S_IRUGO, NULL,
 851                                  NULL, &virq_debug_fops) == NULL)
 852                 return -ENOMEM;
 853
 854         return 0;
 855 }
 856 __initcall(irq_debugfs_init);
 857 #endif /* CONFIG_IRQ_DOMAIN_DEBUG */
 858
 859 /**
 860  * irq_domain_xlate_onecell() - Generic xlate for direct one cell bindings
 861  *
 862  * Device Tree IRQ specifier translation function which works with one cell
 863  * bindings where the cell value maps directly to the hwirq number.
 864  */
 865 int irq_domain_xlate_onecell(struct irq_domain *d, struct device_node *ctrlr,
 866                              const u32 *intspec, unsigned int intsize,
 867                              unsigned long *out_hwirq, unsigned int *out_type)
 868 {
 869         if (WARN_ON(intsize < 1))
 870                 return -EINVAL;
 871         *out_hwirq = intspec[0];
 872         *out_type = IRQ_TYPE_NONE;
 873         return 0;
 874 }
 875 EXPORT_SYMBOL_GPL(irq_domain_xlate_onecell);
 876
 877 /**
 878  * irq_domain_xlate_twocell() - Generic xlate for direct two cell bindings
 879  *
 880  * Device Tree IRQ specifier translation function which works with two cell
 881  * bindings where the cell values map directly to the hwirq number
 882  * and linux irq flags.
 883  */
 884 int irq_domain_xlate_twocell(struct irq_domain *d, struct device_node *ctrlr,
 885                         const u32 *intspec, unsigned int intsize,
 886                         irq_hw_number_t *out_hwirq, unsigned int *out_type)
 887 {
 888         if (WARN_ON(intsize < 2))
 889                 return -EINVAL;
 890         *out_hwirq = intspec[0];
 891         *out_type = intspec[1] & IRQ_TYPE_SENSE_MASK;
 892         return 0;
 893 }
 894 EXPORT_SYMBOL_GPL(irq_domain_xlate_twocell);
 895
 896 /**
 897  * irq_domain_xlate_onetwocell() - Generic xlate for one or two cell bindings
 898  *
 899  * Device Tree IRQ specifier translation function which works with either one
 900  * or two cell bindings where the cell values map directly to the hwirq number
 901  * and linux irq flags.
 902  *
 903  * Note: don't use this function unless your interrupt controller explicitly
 904  * supports both one and two cell bindings.  For the majority of controllers
 905  * the _onecell() or _twocell() variants above should be used.
 906  */
 907 int irq_domain_xlate_onetwocell(struct irq_domain *d,
 908                                 struct device_node *ctrlr,
 909                                 const u32 *intspec, unsigned int intsize,
 910                                 unsigned long *out_hwirq, unsigned int *out_type)
 911 {
 912         if (WARN_ON(intsize < 1))
 913                 return -EINVAL;
 914         *out_hwirq = intspec[0];
 915         *out_type = (intsize > 1) ? intspec[1] : IRQ_TYPE_NONE;
 916         return 0;
 917 }
 918 EXPORT_SYMBOL_GPL(irq_domain_xlate_onetwocell);
 919
 920 const struct irq_domain_ops irq_domain_simple_ops = {
 921         .xlate = irq_domain_xlate_onetwocell,
 922 };
 923 EXPORT_SYMBOL_GPL(irq_domain_simple_ops);
 924
 925 #ifdef CONFIG_OF_IRQ
 926 void irq_domain_generate_simple(const struct of_device_id *match,
 927                                 u64 phys_base, unsigned int irq_start)
 928 {
 929         struct device_node *node;
 930         pr_debug("looking for phys_base=%llx, irq_start=%i\n",
 931                 (unsigned long long) phys_base, (int) irq_start);
 932         node = of_find_matching_node_by_address(NULL, match, phys_base);
 933         if (node)
 934                 irq_domain_add_legacy(node, 32, irq_start, 0,
 935                                       &irq_domain_simple_ops, NULL);
 936 }
 937 EXPORT_SYMBOL_GPL(irq_domain_generate_simple);
 938 #endif