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 #define IRQ_DOMAIN_MAP_LEGACY 0 /* driver allocated fixed range of irqs.
  20                                  * ie. legacy 8259, gets irqs 1..15 */
  21 #define IRQ_DOMAIN_MAP_NOMAP 1 /* no fast reverse mapping */
  22 #define IRQ_DOMAIN_MAP_LINEAR 2 /* linear map of interrupts */
  23 #define IRQ_DOMAIN_MAP_TREE 3 /* radix tree */
  24
  25 static LIST_HEAD(irq_domain_list);
  26 static DEFINE_MUTEX(irq_domain_mutex);
  27
  28 static DEFINE_MUTEX(revmap_trees_mutex);
  29 static struct irq_domain *irq_default_domain;
  30
  31 /**
  32  * irq_domain_alloc() - Allocate a new irq_domain data structure
  33  * @of_node: optional device-tree node of the interrupt controller
  34  * @revmap_type: type of reverse mapping to use
  35  * @ops: map/unmap domain callbacks
  36  * @host_data: Controller private data pointer
  37  *
  38  * Allocates and initialize and irq_domain structure.  Caller is expected to
  39  * register allocated irq_domain with irq_domain_register().  Returns pointer
  40  * to IRQ domain, or NULL on failure.
  41  */
  42 static struct irq_domain *irq_domain_alloc(struct device_node *of_node,
  43                                            unsigned int revmap_type,
  44                                            const struct irq_domain_ops *ops,
  45                                            void *host_data)
  46 {
  47         struct irq_domain *domain;
  48
  49         domain = kzalloc_node(sizeof(*domain), GFP_KERNEL,
  50                               of_node_to_nid(of_node));
  51         if (WARN_ON(!domain))
  52                 return NULL;
  53
  54         /* Fill structure */
  55         domain->revmap_type = revmap_type;
  56         domain->ops = ops;
  57         domain->host_data = host_data;
  58         domain->of_node = of_node_get(of_node);
  59
  60         return domain;
  61 }
  62
  63 static void irq_domain_free(struct irq_domain *domain)
  64 {
  65         of_node_put(domain->of_node);
  66         kfree(domain);
  67 }
  68
  69 static void irq_domain_add(struct irq_domain *domain)
  70 {
  71         mutex_lock(&irq_domain_mutex);
  72         list_add(&domain->link, &irq_domain_list);
  73         mutex_unlock(&irq_domain_mutex);
  74         pr_debug("Allocated domain of type %d @0x%p\n",
  75                  domain->revmap_type, domain);
  76 }
  77
  78 /**
  79  * irq_domain_remove() - Remove an irq domain.
  80  * @domain: domain to remove
  81  *
  82  * This routine is used to remove an irq domain. The caller must ensure
  83  * that all mappings within the domain have been disposed of prior to
  84  * use, depending on the revmap type.
  85  */
  86 void irq_domain_remove(struct irq_domain *domain)
  87 {
  88         mutex_lock(&irq_domain_mutex);
  89
  90         switch (domain->revmap_type) {
  91         case IRQ_DOMAIN_MAP_LEGACY:
  92                 /*
  93                  * Legacy domains don't manage their own irq_desc
  94                  * allocations, we expect the caller to handle irq_desc
  95                  * freeing on their own.
  96                  */
  97                 break;
  98         case IRQ_DOMAIN_MAP_TREE:
  99                 /*
 100                  * radix_tree_delete() takes care of destroying the root
 101                  * node when all entries are removed. Shout if there are
 102                  * any mappings left.
 103                  */
 104                 WARN_ON(domain->revmap_data.tree.height);
 105                 break;
 106         case IRQ_DOMAIN_MAP_LINEAR:
 107                 kfree(domain->revmap_data.linear.revmap);
 108                 domain->revmap_data.linear.size = 0;
 109                 break;
 110         case IRQ_DOMAIN_MAP_NOMAP:
 111                 break;
 112         }
 113
 114         list_del(&domain->link);
 115
 116         /*
 117          * If the going away domain is the default one, reset it.
 118          */
 119         if (unlikely(irq_default_domain == domain))
 120                 irq_set_default_host(NULL);
 121
 122         mutex_unlock(&irq_domain_mutex);
 123
 124         pr_debug("Removed domain of type %d @0x%p\n",
 125                  domain->revmap_type, domain);
 126
 127         irq_domain_free(domain);
 128 }
 129 EXPORT_SYMBOL_GPL(irq_domain_remove);
 130
 131 static unsigned int irq_domain_legacy_revmap(struct irq_domain *domain,
 132                                              irq_hw_number_t hwirq)
 133 {
 134         irq_hw_number_t first_hwirq = domain->revmap_data.legacy.first_hwirq;
 135         int size = domain->revmap_data.legacy.size;
 136
 137         if (WARN_ON(hwirq < first_hwirq || hwirq >= first_hwirq + size))
 138                 return 0;
 139         return hwirq - first_hwirq + domain->revmap_data.legacy.first_irq;
 140 }
 141
 142 /**
 143  * irq_domain_add_simple() - Allocate and register a simple irq_domain.
 144  * @of_node: pointer to interrupt controller's device tree node.
 145  * @size: total number of irqs in mapping
 146  * @first_irq: first number of irq block assigned to the domain
 147  * @ops: map/unmap domain callbacks
 148  * @host_data: Controller private data pointer
 149  *
 150  * Allocates a legacy irq_domain if irq_base is positive or a linear
 151  * domain otherwise. For the legacy domain, IRQ descriptors will also
 152  * be allocated.
 153  *
 154  * This is intended to implement the expected behaviour for most
 155  * interrupt controllers which is that a linear mapping should
 156  * normally be used unless the system requires a legacy mapping in
 157  * order to support supplying interrupt numbers during non-DT
 158  * registration of devices.
 159  */
 160 struct irq_domain *irq_domain_add_simple(struct device_node *of_node,
 161                                          unsigned int size,
 162                                          unsigned int first_irq,
 163                                          const struct irq_domain_ops *ops,
 164                                          void *host_data)
 165 {
 166         if (first_irq > 0) {
 167                 int irq_base;
 168
 169                 if (IS_ENABLED(CONFIG_SPARSE_IRQ)) {
 170                         /*
 171                          * Set the descriptor allocator to search for a
 172                          * 1-to-1 mapping, such as irq_alloc_desc_at().
 173                          * Use of_node_to_nid() which is defined to
 174                          * numa_node_id() on platforms that have no custom
 175                          * implementation.
 176                          */
 177                         irq_base = irq_alloc_descs(first_irq, first_irq, size,
 178                                                    of_node_to_nid(of_node));
 179                         if (irq_base < 0) {
 180                                 pr_info("Cannot allocate irq_descs @ IRQ%d, assuming pre-allocated\n",
 181                                         first_irq);
 182                                 irq_base = first_irq;
 183                         }
 184                 } else
 185                         irq_base = first_irq;
 186
 187                 return irq_domain_add_legacy(of_node, size, irq_base, 0,
 188                                              ops, host_data);
 189         }
 190
 191         /* A linear domain is the default */
 192         return irq_domain_add_linear(of_node, size, ops, host_data);
 193 }
 194
 195 /**
 196  * irq_domain_add_legacy() - Allocate and register a legacy revmap irq_domain.
 197  * @of_node: pointer to interrupt controller's device tree node.
 198  * @size: total number of irqs in legacy mapping
 199  * @first_irq: first number of irq block assigned to the domain
 200  * @first_hwirq: first hwirq number to use for the translation. Should normally
 201  *               be '0', but a positive integer can be used if the effective
 202  *               hwirqs numbering does not begin at zero.
 203  * @ops: map/unmap domain callbacks
 204  * @host_data: Controller private data pointer
 205  *
 206  * Note: the map() callback will be called before this function returns
 207  * for all legacy interrupts except 0 (which is always the invalid irq for
 208  * a legacy controller).
 209  */
 210 struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
 211                                          unsigned int size,
 212                                          unsigned int first_irq,
 213                                          irq_hw_number_t first_hwirq,
 214                                          const struct irq_domain_ops *ops,
 215                                          void *host_data)
 216 {
 217         struct irq_domain *domain;
 218         unsigned int i;
 219
 220         domain = irq_domain_alloc(of_node, IRQ_DOMAIN_MAP_LEGACY, ops, host_data);
 221         if (!domain)
 222                 return NULL;
 223
 224         domain->revmap_data.legacy.first_irq = first_irq;
 225         domain->revmap_data.legacy.first_hwirq = first_hwirq;
 226         domain->revmap_data.legacy.size = size;
 227
 228         mutex_lock(&irq_domain_mutex);
 229         /* Verify that all the irqs are available */
 230         for (i = 0; i < size; i++) {
 231                 int irq = first_irq + i;
 232                 struct irq_data *irq_data = irq_get_irq_data(irq);
 233
 234                 if (WARN_ON(!irq_data || irq_data->domain)) {
 235                         mutex_unlock(&irq_domain_mutex);
 236                         irq_domain_free(domain);
 237                         return NULL;
 238                 }
 239         }
 240
 241         /* Claim all of the irqs before registering a legacy domain */
 242         for (i = 0; i < size; i++) {
 243                 struct irq_data *irq_data = irq_get_irq_data(first_irq + i);
 244                 irq_data->hwirq = first_hwirq + i;
 245                 irq_data->domain = domain;
 246         }
 247         mutex_unlock(&irq_domain_mutex);
 248
 249         for (i = 0; i < size; i++) {
 250                 int irq = first_irq + i;
 251                 int hwirq = first_hwirq + i;
 252
 253                 /* IRQ0 gets ignored */
 254                 if (!irq)
 255                         continue;
 256
 257                 /* Legacy flags are left to default at this point,
 258                  * one can then use irq_create_mapping() to
 259                  * explicitly change them
 260                  */
 261                 if (ops->map)
 262                         ops->map(domain, irq, hwirq);
 263
 264                 /* Clear norequest flags */
 265                 irq_clear_status_flags(irq, IRQ_NOREQUEST);
 266         }
 267
 268         irq_domain_add(domain);
 269         return domain;
 270 }
 271 EXPORT_SYMBOL_GPL(irq_domain_add_legacy);
 272
 273 /**
 274  * irq_domain_add_linear() - Allocate and register a linear revmap irq_domain.
 275  * @of_node: pointer to interrupt controller's device tree node.
 276  * @size: Number of interrupts in the domain.
 277  * @ops: map/unmap domain callbacks
 278  * @host_data: Controller private data pointer
 279  */
 280 struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
 281                                          unsigned int size,
 282                                          const struct irq_domain_ops *ops,
 283                                          void *host_data)
 284 {
 285         struct irq_domain *domain;
 286         unsigned int *revmap;
 287
 288         revmap = kzalloc_node(sizeof(*revmap) * size, GFP_KERNEL,
 289                               of_node_to_nid(of_node));
 290         if (WARN_ON(!revmap))
 291                 return NULL;
 292
 293         domain = irq_domain_alloc(of_node, IRQ_DOMAIN_MAP_LINEAR, ops, host_data);
 294         if (!domain) {
 295                 kfree(revmap);
 296                 return NULL;
 297         }
 298         domain->revmap_data.linear.size = size;
 299         domain->revmap_data.linear.revmap = revmap;
 300         irq_domain_add(domain);
 301         return domain;
 302 }
 303 EXPORT_SYMBOL_GPL(irq_domain_add_linear);
 304
 305 struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
 306                                          unsigned int max_irq,
 307                                          const struct irq_domain_ops *ops,
 308                                          void *host_data)
 309 {
 310         struct irq_domain *domain = irq_domain_alloc(of_node,
 311                                         IRQ_DOMAIN_MAP_NOMAP, ops, host_data);
 312         if (domain) {
 313                 domain->revmap_data.nomap.max_irq = max_irq ? max_irq : ~0;
 314                 irq_domain_add(domain);
 315         }
 316         return domain;
 317 }
 318 EXPORT_SYMBOL_GPL(irq_domain_add_nomap);
 319
 320 /**
 321  * irq_domain_add_tree()
 322  * @of_node: pointer to interrupt controller's device tree node.
 323  * @ops: map/unmap domain callbacks
 324  *
 325  * Note: The radix tree will be allocated later during boot automatically
 326  * (the reverse mapping will use the slow path until that happens).
 327  */
 328 struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
 329                                          const struct irq_domain_ops *ops,
 330                                          void *host_data)
 331 {
 332         struct irq_domain *domain = irq_domain_alloc(of_node,
 333                                         IRQ_DOMAIN_MAP_TREE, ops, host_data);
 334         if (domain) {
 335                 INIT_RADIX_TREE(&domain->revmap_data.tree, GFP_KERNEL);
 336                 irq_domain_add(domain);
 337         }
 338         return domain;
 339 }
 340 EXPORT_SYMBOL_GPL(irq_domain_add_tree);
 341
 342 /**
 343  * irq_find_host() - Locates a domain for a given device node
 344  * @node: device-tree node of the interrupt controller
 345  */
 346 struct irq_domain *irq_find_host(struct device_node *node)
 347 {
 348         struct irq_domain *h, *found = NULL;
 349         int rc;
 350
 351         /* We might want to match the legacy controller last since
 352          * it might potentially be set to match all interrupts in
 353          * the absence of a device node. This isn't a problem so far
 354          * yet though...
 355          */
 356         mutex_lock(&irq_domain_mutex);
 357         list_for_each_entry(h, &irq_domain_list, link) {
 358                 if (h->ops->match)
 359                         rc = h->ops->match(h, node);
 360                 else
 361                         rc = (h->of_node != NULL) && (h->of_node == node);
 362
 363                 if (rc) {
 364                         found = h;
 365                         break;
 366                 }
 367         }
 368         mutex_unlock(&irq_domain_mutex);
 369         return found;
 370 }
 371 EXPORT_SYMBOL_GPL(irq_find_host);
 372
 373 /**
 374  * irq_set_default_host() - Set a "default" irq domain
 375  * @domain: default domain pointer
 376  *
 377  * For convenience, it's possible to set a "default" domain that will be used
 378  * whenever NULL is passed to irq_create_mapping(). It makes life easier for
 379  * platforms that want to manipulate a few hard coded interrupt numbers that
 380  * aren't properly represented in the device-tree.
 381  */
 382 void irq_set_default_host(struct irq_domain *domain)
 383 {
 384         pr_debug("Default domain set to @0x%p\n", domain);
 385
 386         irq_default_domain = domain;
 387 }
 388 EXPORT_SYMBOL_GPL(irq_set_default_host);
 389
 390 static void irq_domain_disassociate_many(struct irq_domain *domain,
 391                                          unsigned int irq_base, int count)
 392 {
 393         /*
 394          * disassociate in reverse order;
 395          * not strictly necessary, but nice for unwinding
 396          */
 397         while (count--) {
 398                 int irq = irq_base + count;
 399                 struct irq_data *irq_data = irq_get_irq_data(irq);
 400                 irq_hw_number_t hwirq = irq_data->hwirq;
 401
 402                 if (WARN_ON(!irq_data || irq_data->domain != domain))
 403                         continue;
 404
 405                 irq_set_status_flags(irq, IRQ_NOREQUEST);
 406
 407                 /* remove chip and handler */
 408                 irq_set_chip_and_handler(irq, NULL, NULL);
 409
 410                 /* Make sure it's completed */
 411                 synchronize_irq(irq);
 412
 413                 /* Tell the PIC about it */
 414                 if (domain->ops->unmap)
 415                         domain->ops->unmap(domain, irq);
 416                 smp_mb();
 417
 418                 irq_data->domain = NULL;
 419                 irq_data->hwirq = 0;
 420
 421                 /* Clear reverse map */
 422                 switch(domain->revmap_type) {
 423                 case IRQ_DOMAIN_MAP_LINEAR:
 424                         if (hwirq < domain->revmap_data.linear.size)
 425                                 domain->revmap_data.linear.revmap[hwirq] = 0;
 426                         break;
 427                 case IRQ_DOMAIN_MAP_TREE:
 428                         mutex_lock(&revmap_trees_mutex);
 429                         radix_tree_delete(&domain->revmap_data.tree, hwirq);
 430                         mutex_unlock(&revmap_trees_mutex);
 431                         break;
 432                 }
 433         }
 434 }
 435
 436 int irq_domain_associate_many(struct irq_domain *domain, unsigned int irq_base,
 437                               irq_hw_number_t hwirq_base, int count)
 438 {
 439         unsigned int virq = irq_base;
 440         irq_hw_number_t hwirq = hwirq_base;
 441         int i, ret;
 442
 443         pr_debug("%s(%s, irqbase=%i, hwbase=%i, count=%i)\n", __func__,
 444                 of_node_full_name(domain->of_node), irq_base, (int)hwirq_base, count);
 445
 446         for (i = 0; i < count; i++) {
 447                 struct irq_data *irq_data = irq_get_irq_data(virq + i);
 448
 449                 if (WARN(!irq_data, "error: irq_desc not allocated; "
 450                          "irq=%i hwirq=0x%x\n", virq + i, (int)hwirq + i))
 451                         return -EINVAL;
 452                 if (WARN(irq_data->domain, "error: irq_desc already associated; "
 453                          "irq=%i hwirq=0x%x\n", virq + i, (int)hwirq + i))
 454                         return -EINVAL;
 455         };
 456
 457         for (i = 0; i < count; i++, virq++, hwirq++) {
 458                 struct irq_data *irq_data = irq_get_irq_data(virq);
 459
 460                 irq_data->hwirq = hwirq;
 461                 irq_data->domain = domain;
 462                 if (domain->ops->map) {
 463                         ret = domain->ops->map(domain, virq, hwirq);
 464                         if (ret != 0) {
 465                                 /*
 466                                  * If map() returns -EPERM, this interrupt is protected
 467                                  * by the firmware or some other service and shall not
 468                                  * be mapped.
 469                                  *
 470                                  * Since on some platforms we blindly try to map everything
 471                                  * we end up with a log full of backtraces.
 472                                  *
 473                                  * So instead, we silently fail on -EPERM, it is the
 474                                  * responsibility of the PIC driver to display a relevant
 475                                  * message if needed.
 476                                  */
 477                                 if (ret != -EPERM) {
 478                                         pr_err("irq-%i==>hwirq-0x%lx mapping failed: %d\n",
 479                                                virq, hwirq, ret);
 480                                         WARN_ON(1);
 481                                 }
 482                                 irq_data->domain = NULL;
 483                                 irq_data->hwirq = 0;
 484                                 goto err_unmap;
 485                         }
 486                 }
 487
 488                 switch (domain->revmap_type) {
 489                 case IRQ_DOMAIN_MAP_LINEAR:
 490                         if (hwirq < domain->revmap_data.linear.size)
 491                                 domain->revmap_data.linear.revmap[hwirq] = virq;
 492                         break;
 493                 case IRQ_DOMAIN_MAP_TREE:
 494                         mutex_lock(&revmap_trees_mutex);
 495                         radix_tree_insert(&domain->revmap_data.tree, hwirq, irq_data);
 496                         mutex_unlock(&revmap_trees_mutex);
 497                         break;
 498                 }
 499
 500                 irq_clear_status_flags(virq, IRQ_NOREQUEST);
 501         }
 502
 503         return 0;
 504
 505  err_unmap:
 506         irq_domain_disassociate_many(domain, irq_base, i);
 507         return -EINVAL;
 508 }
 509 EXPORT_SYMBOL_GPL(irq_domain_associate_many);
 510
 511 /**
 512  * irq_create_direct_mapping() - Allocate an irq for direct mapping
 513  * @domain: domain to allocate the irq for or NULL for default domain
 514  *
 515  * This routine is used for irq controllers which can choose the hardware
 516  * interrupt numbers they generate. In such a case it's simplest to use
 517  * the linux irq as the hardware interrupt number.
 518  */
 519 unsigned int irq_create_direct_mapping(struct irq_domain *domain)
 520 {
 521         unsigned int virq;
 522
 523         if (domain == NULL)
 524                 domain = irq_default_domain;
 525
 526         if (WARN_ON(!domain || domain->revmap_type != IRQ_DOMAIN_MAP_NOMAP))
 527                 return 0;
 528
 529         virq = irq_alloc_desc_from(1, of_node_to_nid(domain->of_node));
 530         if (!virq) {
 531                 pr_debug("create_direct virq allocation failed\n");
 532                 return 0;
 533         }
 534         if (virq >= domain->revmap_data.nomap.max_irq) {
 535                 pr_err("ERROR: no free irqs available below %i maximum\n",
 536                         domain->revmap_data.nomap.max_irq);
 537                 irq_free_desc(virq);
 538                 return 0;
 539         }
 540         pr_debug("create_direct obtained virq %d\n", virq);
 541
 542         if (irq_domain_associate(domain, virq, virq)) {
 543                 irq_free_desc(virq);
 544                 return 0;
 545         }
 546
 547         return virq;
 548 }
 549 EXPORT_SYMBOL_GPL(irq_create_direct_mapping);
 550
 551 /**
 552  * irq_create_mapping() - Map a hardware interrupt into linux irq space
 553  * @domain: domain owning this hardware interrupt or NULL for default domain
 554  * @hwirq: hardware irq number in that domain space
 555  *
 556  * Only one mapping per hardware interrupt is permitted. Returns a linux
 557  * irq number.
 558  * If the sense/trigger is to be specified, set_irq_type() should be called
 559  * on the number returned from that call.
 560  */
 561 unsigned int irq_create_mapping(struct irq_domain *domain,
 562                                 irq_hw_number_t hwirq)
 563 {
 564         unsigned int hint;
 565         int virq;
 566
 567         pr_debug("irq_create_mapping(0x%p, 0x%lx)\n", domain, hwirq);
 568
 569         /* Look for default domain if nececssary */
 570         if (domain == NULL)
 571                 domain = irq_default_domain;
 572         if (domain == NULL) {
 573                 pr_warning("irq_create_mapping called for"
 574                            " NULL domain, hwirq=%lx\n", hwirq);
 575                 WARN_ON(1);
 576                 return 0;
 577         }
 578         pr_debug("-> using domain @%p\n", domain);
 579
 580         /* Check if mapping already exists */
 581         virq = irq_find_mapping(domain, hwirq);
 582         if (virq) {
 583                 pr_debug("-> existing mapping on virq %d\n", virq);
 584                 return virq;
 585         }
 586
 587         /* Get a virtual interrupt number */
 588         if (domain->revmap_type == IRQ_DOMAIN_MAP_LEGACY)
 589                 return irq_domain_legacy_revmap(domain, hwirq);
 590
 591         /* Allocate a virtual interrupt number */
 592         hint = hwirq % nr_irqs;
 593         if (hint == 0)
 594                 hint++;
 595         virq = irq_alloc_desc_from(hint, of_node_to_nid(domain->of_node));
 596         if (virq <= 0)
 597                 virq = irq_alloc_desc_from(1, of_node_to_nid(domain->of_node));
 598         if (virq <= 0) {
 599                 pr_debug("-> virq allocation failed\n");
 600                 return 0;
 601         }
 602
 603         if (irq_domain_associate(domain, virq, hwirq)) {
 604                 irq_free_desc(virq);
 605                 return 0;
 606         }
 607
 608         pr_debug("irq %lu on domain %s mapped to virtual irq %u\n",
 609                 hwirq, of_node_full_name(domain->of_node), virq);
 610
 611         return virq;
 612 }
 613 EXPORT_SYMBOL_GPL(irq_create_mapping);
 614
 615 /**
 616  * irq_create_strict_mappings() - Map a range of hw irqs to fixed linux irqs
 617  * @domain: domain owning the interrupt range
 618  * @irq_base: beginning of linux IRQ range
 619  * @hwirq_base: beginning of hardware IRQ range
 620  * @count: Number of interrupts to map
 621  *
 622  * This routine is used for allocating and mapping a range of hardware
 623  * irqs to linux irqs where the linux irq numbers are at pre-defined
 624  * locations. For use by controllers that already have static mappings
 625  * to insert in to the domain.
 626  *
 627  * Non-linear users can use irq_create_identity_mapping() for IRQ-at-a-time
 628  * domain insertion.
 629  *
 630  * 0 is returned upon success, while any failure to establish a static
 631  * mapping is treated as an error.
 632  */
 633 int irq_create_strict_mappings(struct irq_domain *domain, unsigned int irq_base,
 634                                irq_hw_number_t hwirq_base, int count)
 635 {
 636         int ret;
 637
 638         ret = irq_alloc_descs(irq_base, irq_base, count,
 639                               of_node_to_nid(domain->of_node));
 640         if (unlikely(ret < 0))
 641                 return ret;
 642
 643         ret = irq_domain_associate_many(domain, irq_base, hwirq_base, count);
 644         if (unlikely(ret < 0)) {
 645                 irq_free_descs(irq_base, count);
 646                 return ret;
 647         }
 648
 649         return 0;
 650 }
 651 EXPORT_SYMBOL_GPL(irq_create_strict_mappings);
 652
 653 unsigned int irq_create_of_mapping(struct device_node *controller,
 654                                    const u32 *intspec, unsigned int intsize)
 655 {
 656         struct irq_domain *domain;
 657         irq_hw_number_t hwirq;
 658         unsigned int type = IRQ_TYPE_NONE;
 659         unsigned int virq;
 660
 661         domain = controller ? irq_find_host(controller) : irq_default_domain;
 662         if (!domain) {
 663 #ifdef CONFIG_MIPS
 664                 /*
 665                  * Workaround to avoid breaking interrupt controller drivers
 666                  * that don't yet register an irq_domain.  This is temporary
 667                  * code. ~~~gcl, Feb 24, 2012
 668                  *
 669                  * Scheduled for removal in Linux v3.6.  That should be enough
 670                  * time.
 671                  */
 672                 if (intsize > 0)
 673                         return intspec[0];
 674 #endif
 675                 pr_warning("no irq domain found for %s !\n",
 676                            of_node_full_name(controller));
 677                 return 0;
 678         }
 679
 680         /* If domain has no translation, then we assume interrupt line */
 681         if (domain->ops->xlate == NULL)
 682                 hwirq = intspec[0];
 683         else {
 684                 if (domain->ops->xlate(domain, controller, intspec, intsize,
 685                                      &hwirq, &type))
 686                         return 0;
 687         }
 688
 689         /* Create mapping */
 690         virq = irq_create_mapping(domain, hwirq);
 691         if (!virq)
 692                 return virq;
 693
 694         /* Set type if specified and different than the current one */
 695         if (type != IRQ_TYPE_NONE &&
 696             type != (irqd_get_trigger_type(irq_get_irq_data(virq))))
 697                 irq_set_irq_type(virq, type);
 698         return virq;
 699 }
 700 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
 701
 702 /**
 703  * irq_dispose_mapping() - Unmap an interrupt
 704  * @virq: linux irq number of the interrupt to unmap
 705  */
 706 void irq_dispose_mapping(unsigned int virq)
 707 {
 708         struct irq_data *irq_data = irq_get_irq_data(virq);
 709         struct irq_domain *domain;
 710
 711         if (!virq || !irq_data)
 712                 return;
 713
 714         domain = irq_data->domain;
 715         if (WARN_ON(domain == NULL))
 716                 return;
 717
 718         /* Never unmap legacy interrupts */
 719         if (domain->revmap_type == IRQ_DOMAIN_MAP_LEGACY)
 720                 return;
 721
 722         irq_domain_disassociate_many(domain, virq, 1);
 723         irq_free_desc(virq);
 724 }
 725 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
 726
 727 /**
 728  * irq_find_mapping() - Find a linux irq from an hw irq number.
 729  * @domain: domain owning this hardware interrupt
 730  * @hwirq: hardware irq number in that domain space
 731  */
 732 unsigned int irq_find_mapping(struct irq_domain *domain,
 733                               irq_hw_number_t hwirq)
 734 {
 735         struct irq_data *data;
 736
 737         /* Look for default domain if nececssary */
 738         if (domain == NULL)
 739                 domain = irq_default_domain;
 740         if (domain == NULL)
 741                 return 0;
 742
 743         switch (domain->revmap_type) {
 744         case IRQ_DOMAIN_MAP_LEGACY:
 745                 return irq_domain_legacy_revmap(domain, hwirq);
 746         case IRQ_DOMAIN_MAP_LINEAR:
 747                 return irq_linear_revmap(domain, hwirq);
 748         case IRQ_DOMAIN_MAP_TREE:
 749                 rcu_read_lock();
 750                 data = radix_tree_lookup(&domain->revmap_data.tree, hwirq);
 751                 rcu_read_unlock();
 752                 if (data)
 753                         return data->irq;
 754                 break;
 755         case IRQ_DOMAIN_MAP_NOMAP:
 756                 data = irq_get_irq_data(hwirq);
 757                 if (data && (data->domain == domain) && (data->hwirq == hwirq))
 758                         return hwirq;
 759                 break;
 760         }
 761
 762         return 0;
 763 }
 764 EXPORT_SYMBOL_GPL(irq_find_mapping);
 765
 766 /**
 767  * irq_linear_revmap() - Find a linux irq from a hw irq number.
 768  * @domain: domain owning this hardware interrupt
 769  * @hwirq: hardware irq number in that domain space
 770  *
 771  * This is a fast path that can be called directly by irq controller code to
 772  * save a handful of instructions.
 773  */
 774 unsigned int irq_linear_revmap(struct irq_domain *domain,
 775                                irq_hw_number_t hwirq)
 776 {
 777         BUG_ON(domain->revmap_type != IRQ_DOMAIN_MAP_LINEAR);
 778
 779         /* Check revmap bounds; complain if exceeded */
 780         if (WARN_ON(hwirq >= domain->revmap_data.linear.size))
 781                 return 0;
 782
 783         return domain->revmap_data.linear.revmap[hwirq];
 784 }
 785 EXPORT_SYMBOL_GPL(irq_linear_revmap);
 786
 787 #ifdef CONFIG_IRQ_DOMAIN_DEBUG
 788 static int virq_debug_show(struct seq_file *m, void *private)
 789 {
 790         unsigned long flags;
 791         struct irq_desc *desc;
 792         const char *p;
 793         static const char none[] = "none";
 794         void *data;
 795         int i;
 796
 797         seq_printf(m, "%-5s  %-7s  %-15s  %-*s  %s\n", "irq", "hwirq",
 798                       "chip name", (int)(2 * sizeof(void *) + 2), "chip data",
 799                       "domain name");
 800
 801         for (i = 1; i < nr_irqs; i++) {
 802                 desc = irq_to_desc(i);
 803                 if (!desc)
 804                         continue;
 805
 806                 raw_spin_lock_irqsave(&desc->lock, flags);
 807
 808                 if (desc->action && desc->action->handler) {
 809                         struct irq_chip *chip;
 810
 811                         seq_printf(m, "%5d  ", i);
 812                         seq_printf(m, "0x%05lx  ", desc->irq_data.hwirq);
 813
 814                         chip = irq_desc_get_chip(desc);
 815                         if (chip && chip->name)
 816                                 p = chip->name;
 817                         else
 818                                 p = none;
 819                         seq_printf(m, "%-15s  ", p);
 820
 821                         data = irq_desc_get_chip_data(desc);
 822                         seq_printf(m, data ? "0x%p  " : "  %p  ", data);
 823
 824                         if (desc->irq_data.domain)
 825                                 p = of_node_full_name(desc->irq_data.domain->of_node);
 826                         else
 827                                 p = none;
 828                         seq_printf(m, "%s\n", p);
 829                 }
 830
 831                 raw_spin_unlock_irqrestore(&desc->lock, flags);
 832         }
 833
 834         return 0;
 835 }
 836
 837 static int virq_debug_open(struct inode *inode, struct file *file)
 838 {
 839         return single_open(file, virq_debug_show, inode->i_private);
 840 }
 841
 842 static const struct file_operations virq_debug_fops = {
 843         .open = virq_debug_open,
 844         .read = seq_read,
 845         .llseek = seq_lseek,
 846         .release = single_release,
 847 };
 848
 849 static int __init irq_debugfs_init(void)
 850 {
 851         if (debugfs_create_file("irq_domain_mapping", S_IRUGO, NULL,
 852                                  NULL, &virq_debug_fops) == NULL)
 853                 return -ENOMEM;
 854
 855         return 0;
 856 }
 857 __initcall(irq_debugfs_init);
 858 #endif /* CONFIG_IRQ_DOMAIN_DEBUG */
 859
 860 /**
 861  * irq_domain_xlate_onecell() - Generic xlate for direct one cell bindings
 862  *
 863  * Device Tree IRQ specifier translation function which works with one cell
 864  * bindings where the cell value maps directly to the hwirq number.
 865  */
 866 int irq_domain_xlate_onecell(struct irq_domain *d, struct device_node *ctrlr,
 867                              const u32 *intspec, unsigned int intsize,
 868                              unsigned long *out_hwirq, unsigned int *out_type)
 869 {
 870         if (WARN_ON(intsize < 1))
 871                 return -EINVAL;
 872         *out_hwirq = intspec[0];
 873         *out_type = IRQ_TYPE_NONE;
 874         return 0;
 875 }
 876 EXPORT_SYMBOL_GPL(irq_domain_xlate_onecell);
 877
 878 /**
 879  * irq_domain_xlate_twocell() - Generic xlate for direct two cell bindings
 880  *
 881  * Device Tree IRQ specifier translation function which works with two cell
 882  * bindings where the cell values map directly to the hwirq number
 883  * and linux irq flags.
 884  */
 885 int irq_domain_xlate_twocell(struct irq_domain *d, struct device_node *ctrlr,
 886                         const u32 *intspec, unsigned int intsize,
 887                         irq_hw_number_t *out_hwirq, unsigned int *out_type)
 888 {
 889         if (WARN_ON(intsize < 2))
 890                 return -EINVAL;
 891         *out_hwirq = intspec[0];
 892         *out_type = intspec[1] & IRQ_TYPE_SENSE_MASK;
 893         return 0;
 894 }
 895 EXPORT_SYMBOL_GPL(irq_domain_xlate_twocell);
 896
 897 /**
 898  * irq_domain_xlate_onetwocell() - Generic xlate for one or two cell bindings
 899  *
 900  * Device Tree IRQ specifier translation function which works with either one
 901  * or two cell bindings where the cell values map directly to the hwirq number
 902  * and linux irq flags.
 903  *
 904  * Note: don't use this function unless your interrupt controller explicitly
 905  * supports both one and two cell bindings.  For the majority of controllers
 906  * the _onecell() or _twocell() variants above should be used.
 907  */
 908 int irq_domain_xlate_onetwocell(struct irq_domain *d,
 909                                 struct device_node *ctrlr,
 910                                 const u32 *intspec, unsigned int intsize,
 911                                 unsigned long *out_hwirq, unsigned int *out_type)
 912 {
 913         if (WARN_ON(intsize < 1))
 914                 return -EINVAL;
 915         *out_hwirq = intspec[0];
 916         *out_type = (intsize > 1) ? intspec[1] : IRQ_TYPE_NONE;
 917         return 0;
 918 }
 919 EXPORT_SYMBOL_GPL(irq_domain_xlate_onetwocell);
 920
 921 const struct irq_domain_ops irq_domain_simple_ops = {
 922         .xlate = irq_domain_xlate_onetwocell,
 923 };
 924 EXPORT_SYMBOL_GPL(irq_domain_simple_ops);
 925
 926 #ifdef CONFIG_OF_IRQ
 927 void irq_domain_generate_simple(const struct of_device_id *match,
 928                                 u64 phys_base, unsigned int irq_start)
 929 {
 930         struct device_node *node;
 931         pr_debug("looking for phys_base=%llx, irq_start=%i\n",
 932                 (unsigned long long) phys_base, (int) irq_start);
 933         node = of_find_matching_node_by_address(NULL, match, phys_base);
 934         if (node)
 935                 irq_domain_add_legacy(node, 32, irq_start, 0,
 936                                       &irq_domain_simple_ops, NULL);
 937 }
 938 EXPORT_SYMBOL_GPL(irq_domain_generate_simple);
 939 #endif