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  *      pass zero to assign irqs on-the-fly. This will result in a
 148  *      linear IRQ domain so it is important to use irq_create_mapping()
 149  *      for each used IRQ, especially when SPARSE_IRQ is enabled.
 150  * @ops: map/unmap domain callbacks
 151  * @host_data: Controller private data pointer
 152  *
 153  * Allocates a legacy irq_domain if irq_base is positive or a linear
 154  * domain otherwise. For the legacy domain, IRQ descriptors will also
 155  * be allocated.
 156  *
 157  * This is intended to implement the expected behaviour for most
 158  * interrupt controllers which is that a linear mapping should
 159  * normally be used unless the system requires a legacy mapping in
 160  * order to support supplying interrupt numbers during non-DT
 161  * registration of devices.
 162  */
 163 struct irq_domain *irq_domain_add_simple(struct device_node *of_node,
 164                                          unsigned int size,
 165                                          unsigned int first_irq,
 166                                          const struct irq_domain_ops *ops,
 167                                          void *host_data)
 168 {
 169         if (first_irq > 0) {
 170                 int irq_base;
 171
 172                 if (IS_ENABLED(CONFIG_SPARSE_IRQ)) {
 173                         /*
 174                          * Set the descriptor allocator to search for a
 175                          * 1-to-1 mapping, such as irq_alloc_desc_at().
 176                          * Use of_node_to_nid() which is defined to
 177                          * numa_node_id() on platforms that have no custom
 178                          * implementation.
 179                          */
 180                         irq_base = irq_alloc_descs(first_irq, first_irq, size,
 181                                                    of_node_to_nid(of_node));
 182                         if (irq_base < 0) {
 183                                 pr_info("Cannot allocate irq_descs @ IRQ%d, assuming pre-allocated\n",
 184                                         first_irq);
 185                                 irq_base = first_irq;
 186                         }
 187                 } else
 188                         irq_base = first_irq;
 189
 190                 return irq_domain_add_legacy(of_node, size, irq_base, 0,
 191                                              ops, host_data);
 192         }
 193
 194         /* A linear domain is the default */
 195         return irq_domain_add_linear(of_node, size, ops, host_data);
 196 }
 197 EXPORT_SYMBOL_GPL(irq_domain_add_simple);
 198
 199 /**
 200  * irq_domain_add_legacy() - Allocate and register a legacy revmap irq_domain.
 201  * @of_node: pointer to interrupt controller's device tree node.
 202  * @size: total number of irqs in legacy mapping
 203  * @first_irq: first number of irq block assigned to the domain
 204  * @first_hwirq: first hwirq number to use for the translation. Should normally
 205  *               be '0', but a positive integer can be used if the effective
 206  *               hwirqs numbering does not begin at zero.
 207  * @ops: map/unmap domain callbacks
 208  * @host_data: Controller private data pointer
 209  *
 210  * Note: the map() callback will be called before this function returns
 211  * for all legacy interrupts except 0 (which is always the invalid irq for
 212  * a legacy controller).
 213  */
 214 struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
 215                                          unsigned int size,
 216                                          unsigned int first_irq,
 217                                          irq_hw_number_t first_hwirq,
 218                                          const struct irq_domain_ops *ops,
 219                                          void *host_data)
 220 {
 221         struct irq_domain *domain;
 222         unsigned int i;
 223
 224         domain = irq_domain_alloc(of_node, IRQ_DOMAIN_MAP_LEGACY, ops, host_data);
 225         if (!domain)
 226                 return NULL;
 227
 228         domain->revmap_data.legacy.first_irq = first_irq;
 229         domain->revmap_data.legacy.first_hwirq = first_hwirq;
 230         domain->revmap_data.legacy.size = size;
 231
 232         mutex_lock(&irq_domain_mutex);
 233         /* Verify that all the irqs are available */
 234         for (i = 0; i < size; i++) {
 235                 int irq = first_irq + i;
 236                 struct irq_data *irq_data = irq_get_irq_data(irq);
 237
 238                 if (WARN_ON(!irq_data || irq_data->domain)) {
 239                         mutex_unlock(&irq_domain_mutex);
 240                         irq_domain_free(domain);
 241                         return NULL;
 242                 }
 243         }
 244
 245         /* Claim all of the irqs before registering a legacy domain */
 246         for (i = 0; i < size; i++) {
 247                 struct irq_data *irq_data = irq_get_irq_data(first_irq + i);
 248                 irq_data->hwirq = first_hwirq + i;
 249                 irq_data->domain = domain;
 250         }
 251         mutex_unlock(&irq_domain_mutex);
 252
 253         for (i = 0; i < size; i++) {
 254                 int irq = first_irq + i;
 255                 int hwirq = first_hwirq + i;
 256
 257                 /* IRQ0 gets ignored */
 258                 if (!irq)
 259                         continue;
 260
 261                 /* Legacy flags are left to default at this point,
 262                  * one can then use irq_create_mapping() to
 263                  * explicitly change them
 264                  */
 265                 if (ops->map)
 266                         ops->map(domain, irq, hwirq);
 267
 268                 /* Clear norequest flags */
 269                 irq_clear_status_flags(irq, IRQ_NOREQUEST);
 270         }
 271
 272         irq_domain_add(domain);
 273         return domain;
 274 }
 275 EXPORT_SYMBOL_GPL(irq_domain_add_legacy);
 276
 277 /**
 278  * irq_domain_add_linear() - Allocate and register a linear revmap irq_domain.
 279  * @of_node: pointer to interrupt controller's device tree node.
 280  * @size: Number of interrupts in the domain.
 281  * @ops: map/unmap domain callbacks
 282  * @host_data: Controller private data pointer
 283  */
 284 struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
 285                                          unsigned int size,
 286                                          const struct irq_domain_ops *ops,
 287                                          void *host_data)
 288 {
 289         struct irq_domain *domain;
 290         unsigned int *revmap;
 291
 292         revmap = kzalloc_node(sizeof(*revmap) * size, GFP_KERNEL,
 293                               of_node_to_nid(of_node));
 294         if (WARN_ON(!revmap))
 295                 return NULL;
 296
 297         domain = irq_domain_alloc(of_node, IRQ_DOMAIN_MAP_LINEAR, ops, host_data);
 298         if (!domain) {
 299                 kfree(revmap);
 300                 return NULL;
 301         }
 302         domain->revmap_data.linear.size = size;
 303         domain->revmap_data.linear.revmap = revmap;
 304         irq_domain_add(domain);
 305         return domain;
 306 }
 307 EXPORT_SYMBOL_GPL(irq_domain_add_linear);
 308
 309 struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
 310                                          unsigned int max_irq,
 311                                          const struct irq_domain_ops *ops,
 312                                          void *host_data)
 313 {
 314         struct irq_domain *domain = irq_domain_alloc(of_node,
 315                                         IRQ_DOMAIN_MAP_NOMAP, ops, host_data);
 316         if (domain) {
 317                 domain->revmap_data.nomap.max_irq = max_irq ? max_irq : ~0;
 318                 irq_domain_add(domain);
 319         }
 320         return domain;
 321 }
 322 EXPORT_SYMBOL_GPL(irq_domain_add_nomap);
 323
 324 /**
 325  * irq_domain_add_tree()
 326  * @of_node: pointer to interrupt controller's device tree node.
 327  * @ops: map/unmap domain callbacks
 328  *
 329  * Note: The radix tree will be allocated later during boot automatically
 330  * (the reverse mapping will use the slow path until that happens).
 331  */
 332 struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
 333                                          const struct irq_domain_ops *ops,
 334                                          void *host_data)
 335 {
 336         struct irq_domain *domain = irq_domain_alloc(of_node,
 337                                         IRQ_DOMAIN_MAP_TREE, ops, host_data);
 338         if (domain) {
 339                 INIT_RADIX_TREE(&domain->revmap_data.tree, GFP_KERNEL);
 340                 irq_domain_add(domain);
 341         }
 342         return domain;
 343 }
 344 EXPORT_SYMBOL_GPL(irq_domain_add_tree);
 345
 346 /**
 347  * irq_find_host() - Locates a domain for a given device node
 348  * @node: device-tree node of the interrupt controller
 349  */
 350 struct irq_domain *irq_find_host(struct device_node *node)
 351 {
 352         struct irq_domain *h, *found = NULL;
 353         int rc;
 354
 355         /* We might want to match the legacy controller last since
 356          * it might potentially be set to match all interrupts in
 357          * the absence of a device node. This isn't a problem so far
 358          * yet though...
 359          */
 360         mutex_lock(&irq_domain_mutex);
 361         list_for_each_entry(h, &irq_domain_list, link) {
 362                 if (h->ops->match)
 363                         rc = h->ops->match(h, node);
 364                 else
 365                         rc = (h->of_node != NULL) && (h->of_node == node);
 366
 367                 if (rc) {
 368                         found = h;
 369                         break;
 370                 }
 371         }
 372         mutex_unlock(&irq_domain_mutex);
 373         return found;
 374 }
 375 EXPORT_SYMBOL_GPL(irq_find_host);
 376
 377 /**
 378  * irq_set_default_host() - Set a "default" irq domain
 379  * @domain: default domain pointer
 380  *
 381  * For convenience, it's possible to set a "default" domain that will be used
 382  * whenever NULL is passed to irq_create_mapping(). It makes life easier for
 383  * platforms that want to manipulate a few hard coded interrupt numbers that
 384  * aren't properly represented in the device-tree.
 385  */
 386 void irq_set_default_host(struct irq_domain *domain)
 387 {
 388         pr_debug("Default domain set to @0x%p\n", domain);
 389
 390         irq_default_domain = domain;
 391 }
 392 EXPORT_SYMBOL_GPL(irq_set_default_host);
 393
 394 static void irq_domain_disassociate_many(struct irq_domain *domain,
 395                                          unsigned int irq_base, int count)
 396 {
 397         /*
 398          * disassociate in reverse order;
 399          * not strictly necessary, but nice for unwinding
 400          */
 401         while (count--) {
 402                 int irq = irq_base + count;
 403                 struct irq_data *irq_data = irq_get_irq_data(irq);
 404                 irq_hw_number_t hwirq;
 405
 406                 if (WARN_ON(!irq_data || irq_data->domain != domain))
 407                         continue;
 408
 409                 hwirq = irq_data->hwirq;
 410                 irq_set_status_flags(irq, IRQ_NOREQUEST);
 411
 412                 /* remove chip and handler */
 413                 irq_set_chip_and_handler(irq, NULL, NULL);
 414
 415                 /* Make sure it's completed */
 416                 synchronize_irq(irq);
 417
 418                 /* Tell the PIC about it */
 419                 if (domain->ops->unmap)
 420                         domain->ops->unmap(domain, irq);
 421                 smp_mb();
 422
 423                 irq_data->domain = NULL;
 424                 irq_data->hwirq = 0;
 425
 426                 /* Clear reverse map */
 427                 switch(domain->revmap_type) {
 428                 case IRQ_DOMAIN_MAP_LINEAR:
 429                         if (hwirq < domain->revmap_data.linear.size)
 430                                 domain->revmap_data.linear.revmap[hwirq] = 0;
 431                         break;
 432                 case IRQ_DOMAIN_MAP_TREE:
 433                         mutex_lock(&revmap_trees_mutex);
 434                         radix_tree_delete(&domain->revmap_data.tree, hwirq);
 435                         mutex_unlock(&revmap_trees_mutex);
 436                         break;
 437                 }
 438         }
 439 }
 440
 441 int irq_domain_associate_many(struct irq_domain *domain, unsigned int irq_base,
 442                               irq_hw_number_t hwirq_base, int count)
 443 {
 444         unsigned int virq = irq_base;
 445         irq_hw_number_t hwirq = hwirq_base;
 446         int i, ret;
 447
 448         pr_debug("%s(%s, irqbase=%i, hwbase=%i, count=%i)\n", __func__,
 449                 of_node_full_name(domain->of_node), irq_base, (int)hwirq_base, count);
 450
 451         for (i = 0; i < count; i++) {
 452                 struct irq_data *irq_data = irq_get_irq_data(virq + i);
 453
 454                 if (WARN(!irq_data, "error: irq_desc not allocated; "
 455                          "irq=%i hwirq=0x%x\n", virq + i, (int)hwirq + i))
 456                         return -EINVAL;
 457                 if (WARN(irq_data->domain, "error: irq_desc already associated; "
 458                          "irq=%i hwirq=0x%x\n", virq + i, (int)hwirq + i))
 459                         return -EINVAL;
 460         };
 461
 462         for (i = 0; i < count; i++, virq++, hwirq++) {
 463                 struct irq_data *irq_data = irq_get_irq_data(virq);
 464
 465                 irq_data->hwirq = hwirq;
 466                 irq_data->domain = domain;
 467                 if (domain->ops->map) {
 468                         ret = domain->ops->map(domain, virq, hwirq);
 469                         if (ret != 0) {
 470                                 /*
 471                                  * If map() returns -EPERM, this interrupt is protected
 472                                  * by the firmware or some other service and shall not
 473                                  * be mapped.
 474                                  *
 475                                  * Since on some platforms we blindly try to map everything
 476                                  * we end up with a log full of backtraces.
 477                                  *
 478                                  * So instead, we silently fail on -EPERM, it is the
 479                                  * responsibility of the PIC driver to display a relevant
 480                                  * message if needed.
 481                                  */
 482                                 if (ret != -EPERM) {
 483                                         pr_err("irq-%i==>hwirq-0x%lx mapping failed: %d\n",
 484                                                virq, hwirq, ret);
 485                                         WARN_ON(1);
 486                                 }
 487                                 irq_data->domain = NULL;
 488                                 irq_data->hwirq = 0;
 489                                 goto err_unmap;
 490                         }
 491                 }
 492
 493                 switch (domain->revmap_type) {
 494                 case IRQ_DOMAIN_MAP_LINEAR:
 495                         if (hwirq < domain->revmap_data.linear.size)
 496                                 domain->revmap_data.linear.revmap[hwirq] = virq;
 497                         break;
 498                 case IRQ_DOMAIN_MAP_TREE:
 499                         mutex_lock(&revmap_trees_mutex);
 500                         radix_tree_insert(&domain->revmap_data.tree, hwirq, irq_data);
 501                         mutex_unlock(&revmap_trees_mutex);
 502                         break;
 503                 }
 504
 505                 irq_clear_status_flags(virq, IRQ_NOREQUEST);
 506         }
 507
 508         return 0;
 509
 510  err_unmap:
 511         irq_domain_disassociate_many(domain, irq_base, i);
 512         return -EINVAL;
 513 }
 514 EXPORT_SYMBOL_GPL(irq_domain_associate_many);
 515
 516 /**
 517  * irq_create_direct_mapping() - Allocate an irq for direct mapping
 518  * @domain: domain to allocate the irq for or NULL for default domain
 519  *
 520  * This routine is used for irq controllers which can choose the hardware
 521  * interrupt numbers they generate. In such a case it's simplest to use
 522  * the linux irq as the hardware interrupt number.
 523  */
 524 unsigned int irq_create_direct_mapping(struct irq_domain *domain)
 525 {
 526         unsigned int virq;
 527
 528         if (domain == NULL)
 529                 domain = irq_default_domain;
 530
 531         if (WARN_ON(!domain || domain->revmap_type != IRQ_DOMAIN_MAP_NOMAP))
 532                 return 0;
 533
 534         virq = irq_alloc_desc_from(1, of_node_to_nid(domain->of_node));
 535         if (!virq) {
 536                 pr_debug("create_direct virq allocation failed\n");
 537                 return 0;
 538         }
 539         if (virq >= domain->revmap_data.nomap.max_irq) {
 540                 pr_err("ERROR: no free irqs available below %i maximum\n",
 541                         domain->revmap_data.nomap.max_irq);
 542                 irq_free_desc(virq);
 543                 return 0;
 544         }
 545         pr_debug("create_direct obtained virq %d\n", virq);
 546
 547         if (irq_domain_associate(domain, virq, virq)) {
 548                 irq_free_desc(virq);
 549                 return 0;
 550         }
 551
 552         return virq;
 553 }
 554 EXPORT_SYMBOL_GPL(irq_create_direct_mapping);
 555
 556 /**
 557  * irq_create_mapping() - Map a hardware interrupt into linux irq space
 558  * @domain: domain owning this hardware interrupt or NULL for default domain
 559  * @hwirq: hardware irq number in that domain space
 560  *
 561  * Only one mapping per hardware interrupt is permitted. Returns a linux
 562  * irq number.
 563  * If the sense/trigger is to be specified, set_irq_type() should be called
 564  * on the number returned from that call.
 565  */
 566 unsigned int irq_create_mapping(struct irq_domain *domain,
 567                                 irq_hw_number_t hwirq)
 568 {
 569         unsigned int hint;
 570         int virq;
 571
 572         pr_debug("irq_create_mapping(0x%p, 0x%lx)\n", domain, hwirq);
 573
 574         /* Look for default domain if nececssary */
 575         if (domain == NULL)
 576                 domain = irq_default_domain;
 577         if (domain == NULL) {
 578                 pr_warning("irq_create_mapping called for"
 579                            " NULL domain, hwirq=%lx\n", hwirq);
 580                 WARN_ON(1);
 581                 return 0;
 582         }
 583         pr_debug("-> using domain @%p\n", domain);
 584
 585         /* Check if mapping already exists */
 586         virq = irq_find_mapping(domain, hwirq);
 587         if (virq) {
 588                 pr_debug("-> existing mapping on virq %d\n", virq);
 589                 return virq;
 590         }
 591
 592         /* Get a virtual interrupt number */
 593         if (domain->revmap_type == IRQ_DOMAIN_MAP_LEGACY)
 594                 return irq_domain_legacy_revmap(domain, hwirq);
 595
 596         /* Allocate a virtual interrupt number */
 597         hint = hwirq % nr_irqs;
 598         if (hint == 0)
 599                 hint++;
 600         virq = irq_alloc_desc_from(hint, of_node_to_nid(domain->of_node));
 601         if (virq <= 0)
 602                 virq = irq_alloc_desc_from(1, of_node_to_nid(domain->of_node));
 603         if (virq <= 0) {
 604                 pr_debug("-> virq allocation failed\n");
 605                 return 0;
 606         }
 607
 608         if (irq_domain_associate(domain, virq, hwirq)) {
 609                 irq_free_desc(virq);
 610                 return 0;
 611         }
 612
 613         pr_debug("irq %lu on domain %s mapped to virtual irq %u\n",
 614                 hwirq, of_node_full_name(domain->of_node), virq);
 615
 616         return virq;
 617 }
 618 EXPORT_SYMBOL_GPL(irq_create_mapping);
 619
 620 /**
 621  * irq_create_strict_mappings() - Map a range of hw irqs to fixed linux irqs
 622  * @domain: domain owning the interrupt range
 623  * @irq_base: beginning of linux IRQ range
 624  * @hwirq_base: beginning of hardware IRQ range
 625  * @count: Number of interrupts to map
 626  *
 627  * This routine is used for allocating and mapping a range of hardware
 628  * irqs to linux irqs where the linux irq numbers are at pre-defined
 629  * locations. For use by controllers that already have static mappings
 630  * to insert in to the domain.
 631  *
 632  * Non-linear users can use irq_create_identity_mapping() for IRQ-at-a-time
 633  * domain insertion.
 634  *
 635  * 0 is returned upon success, while any failure to establish a static
 636  * mapping is treated as an error.
 637  */
 638 int irq_create_strict_mappings(struct irq_domain *domain, unsigned int irq_base,
 639                                irq_hw_number_t hwirq_base, int count)
 640 {
 641         int ret;
 642
 643         ret = irq_alloc_descs(irq_base, irq_base, count,
 644                               of_node_to_nid(domain->of_node));
 645         if (unlikely(ret < 0))
 646                 return ret;
 647
 648         ret = irq_domain_associate_many(domain, irq_base, hwirq_base, count);
 649         if (unlikely(ret < 0)) {
 650                 irq_free_descs(irq_base, count);
 651                 return ret;
 652         }
 653
 654         return 0;
 655 }
 656 EXPORT_SYMBOL_GPL(irq_create_strict_mappings);
 657
 658 unsigned int irq_create_of_mapping(struct device_node *controller,
 659                                    const u32 *intspec, unsigned int intsize)
 660 {
 661         struct irq_domain *domain;
 662         irq_hw_number_t hwirq;
 663         unsigned int type = IRQ_TYPE_NONE;
 664         unsigned int virq;
 665
 666         domain = controller ? irq_find_host(controller) : irq_default_domain;
 667         if (!domain) {
 668 #ifdef CONFIG_MIPS
 669                 /*
 670                  * Workaround to avoid breaking interrupt controller drivers
 671                  * that don't yet register an irq_domain.  This is temporary
 672                  * code. ~~~gcl, Feb 24, 2012
 673                  *
 674                  * Scheduled for removal in Linux v3.6.  That should be enough
 675                  * time.
 676                  */
 677                 if (intsize > 0)
 678                         return intspec[0];
 679 #endif
 680                 pr_warning("no irq domain found for %s !\n",
 681                            of_node_full_name(controller));
 682                 return 0;
 683         }
 684
 685         /* If domain has no translation, then we assume interrupt line */
 686         if (domain->ops->xlate == NULL)
 687                 hwirq = intspec[0];
 688         else {
 689                 if (domain->ops->xlate(domain, controller, intspec, intsize,
 690                                      &hwirq, &type))
 691                         return 0;
 692         }
 693
 694         /* Create mapping */
 695         virq = irq_create_mapping(domain, hwirq);
 696         if (!virq)
 697                 return virq;
 698
 699         /* Set type if specified and different than the current one */
 700         if (type != IRQ_TYPE_NONE &&
 701             type != (irqd_get_trigger_type(irq_get_irq_data(virq))))
 702                 irq_set_irq_type(virq, type);
 703         return virq;
 704 }
 705 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
 706
 707 /**
 708  * irq_dispose_mapping() - Unmap an interrupt
 709  * @virq: linux irq number of the interrupt to unmap
 710  */
 711 void irq_dispose_mapping(unsigned int virq)
 712 {
 713         struct irq_data *irq_data = irq_get_irq_data(virq);
 714         struct irq_domain *domain;
 715
 716         if (!virq || !irq_data)
 717                 return;
 718
 719         domain = irq_data->domain;
 720         if (WARN_ON(domain == NULL))
 721                 return;
 722
 723         /* Never unmap legacy interrupts */
 724         if (domain->revmap_type == IRQ_DOMAIN_MAP_LEGACY)
 725                 return;
 726
 727         irq_domain_disassociate_many(domain, virq, 1);
 728         irq_free_desc(virq);
 729 }
 730 EXPORT_SYMBOL_GPL(irq_dispose_mapping);
 731
 732 /**
 733  * irq_find_mapping() - Find a linux irq from an hw irq number.
 734  * @domain: domain owning this hardware interrupt
 735  * @hwirq: hardware irq number in that domain space
 736  */
 737 unsigned int irq_find_mapping(struct irq_domain *domain,
 738                               irq_hw_number_t hwirq)
 739 {
 740         struct irq_data *data;
 741
 742         /* Look for default domain if nececssary */
 743         if (domain == NULL)
 744                 domain = irq_default_domain;
 745         if (domain == NULL)
 746                 return 0;
 747
 748         switch (domain->revmap_type) {
 749         case IRQ_DOMAIN_MAP_LEGACY:
 750                 return irq_domain_legacy_revmap(domain, hwirq);
 751         case IRQ_DOMAIN_MAP_LINEAR:
 752                 return irq_linear_revmap(domain, hwirq);
 753         case IRQ_DOMAIN_MAP_TREE:
 754                 rcu_read_lock();
 755                 data = radix_tree_lookup(&domain->revmap_data.tree, hwirq);
 756                 rcu_read_unlock();
 757                 if (data)
 758                         return data->irq;
 759                 break;
 760         case IRQ_DOMAIN_MAP_NOMAP:
 761                 data = irq_get_irq_data(hwirq);
 762                 if (data && (data->domain == domain) && (data->hwirq == hwirq))
 763                         return hwirq;
 764                 break;
 765         }
 766
 767         return 0;
 768 }
 769 EXPORT_SYMBOL_GPL(irq_find_mapping);
 770
 771 /**
 772  * irq_linear_revmap() - Find a linux irq from a hw irq number.
 773  * @domain: domain owning this hardware interrupt
 774  * @hwirq: hardware irq number in that domain space
 775  *
 776  * This is a fast path that can be called directly by irq controller code to
 777  * save a handful of instructions.
 778  */
 779 unsigned int irq_linear_revmap(struct irq_domain *domain,
 780                                irq_hw_number_t hwirq)
 781 {
 782         BUG_ON(domain->revmap_type != IRQ_DOMAIN_MAP_LINEAR);
 783
 784         /* Check revmap bounds; complain if exceeded */
 785         if (WARN_ON(hwirq >= domain->revmap_data.linear.size))
 786                 return 0;
 787
 788         return domain->revmap_data.linear.revmap[hwirq];
 789 }
 790 EXPORT_SYMBOL_GPL(irq_linear_revmap);
 791
 792 #ifdef CONFIG_IRQ_DOMAIN_DEBUG
 793 static int virq_debug_show(struct seq_file *m, void *private)
 794 {
 795         unsigned long flags;
 796         struct irq_desc *desc;
 797         const char *p;
 798         static const char none[] = "none";
 799         void *data;
 800         int i;
 801
 802         seq_printf(m, "%-5s  %-7s  %-15s  %-*s  %s\n", "irq", "hwirq",
 803                       "chip name", (int)(2 * sizeof(void *) + 2), "chip data",
 804                       "domain name");
 805
 806         for (i = 1; i < nr_irqs; i++) {
 807                 desc = irq_to_desc(i);
 808                 if (!desc)
 809                         continue;
 810
 811                 raw_spin_lock_irqsave(&desc->lock, flags);
 812
 813                 if (desc->action && desc->action->handler) {
 814                         struct irq_chip *chip;
 815
 816                         seq_printf(m, "%5d  ", i);
 817                         seq_printf(m, "0x%05lx  ", desc->irq_data.hwirq);
 818
 819                         chip = irq_desc_get_chip(desc);
 820                         if (chip && chip->name)
 821                                 p = chip->name;
 822                         else
 823                                 p = none;
 824                         seq_printf(m, "%-15s  ", p);
 825
 826                         data = irq_desc_get_chip_data(desc);
 827                         seq_printf(m, data ? "0x%p  " : "  %p  ", data);
 828
 829                         if (desc->irq_data.domain)
 830                                 p = of_node_full_name(desc->irq_data.domain->of_node);
 831                         else
 832                                 p = none;
 833                         seq_printf(m, "%s\n", p);
 834                 }
 835
 836                 raw_spin_unlock_irqrestore(&desc->lock, flags);
 837         }
 838
 839         return 0;
 840 }
 841
 842 static int virq_debug_open(struct inode *inode, struct file *file)
 843 {
 844         return single_open(file, virq_debug_show, inode->i_private);
 845 }
 846
 847 static const struct file_operations virq_debug_fops = {
 848         .open = virq_debug_open,
 849         .read = seq_read,
 850         .llseek = seq_lseek,
 851         .release = single_release,
 852 };
 853
 854 static int __init irq_debugfs_init(void)
 855 {
 856         if (debugfs_create_file("irq_domain_mapping", S_IRUGO, NULL,
 857                                  NULL, &virq_debug_fops) == NULL)
 858                 return -ENOMEM;
 859
 860         return 0;
 861 }
 862 __initcall(irq_debugfs_init);
 863 #endif /* CONFIG_IRQ_DOMAIN_DEBUG */
 864
 865 /**
 866  * irq_domain_xlate_onecell() - Generic xlate for direct one cell bindings
 867  *
 868  * Device Tree IRQ specifier translation function which works with one cell
 869  * bindings where the cell value maps directly to the hwirq number.
 870  */
 871 int irq_domain_xlate_onecell(struct irq_domain *d, struct device_node *ctrlr,
 872                              const u32 *intspec, unsigned int intsize,
 873                              unsigned long *out_hwirq, unsigned int *out_type)
 874 {
 875         if (WARN_ON(intsize < 1))
 876                 return -EINVAL;
 877         *out_hwirq = intspec[0];
 878         *out_type = IRQ_TYPE_NONE;
 879         return 0;
 880 }
 881 EXPORT_SYMBOL_GPL(irq_domain_xlate_onecell);
 882
 883 /**
 884  * irq_domain_xlate_twocell() - Generic xlate for direct two cell bindings
 885  *
 886  * Device Tree IRQ specifier translation function which works with two cell
 887  * bindings where the cell values map directly to the hwirq number
 888  * and linux irq flags.
 889  */
 890 int irq_domain_xlate_twocell(struct irq_domain *d, struct device_node *ctrlr,
 891                         const u32 *intspec, unsigned int intsize,
 892                         irq_hw_number_t *out_hwirq, unsigned int *out_type)
 893 {
 894         if (WARN_ON(intsize < 2))
 895                 return -EINVAL;
 896         *out_hwirq = intspec[0];
 897         *out_type = intspec[1] & IRQ_TYPE_SENSE_MASK;
 898         return 0;
 899 }
 900 EXPORT_SYMBOL_GPL(irq_domain_xlate_twocell);
 901
 902 /**
 903  * irq_domain_xlate_onetwocell() - Generic xlate for one or two cell bindings
 904  *
 905  * Device Tree IRQ specifier translation function which works with either one
 906  * or two cell bindings where the cell values map directly to the hwirq number
 907  * and linux irq flags.
 908  *
 909  * Note: don't use this function unless your interrupt controller explicitly
 910  * supports both one and two cell bindings.  For the majority of controllers
 911  * the _onecell() or _twocell() variants above should be used.
 912  */
 913 int irq_domain_xlate_onetwocell(struct irq_domain *d,
 914                                 struct device_node *ctrlr,
 915                                 const u32 *intspec, unsigned int intsize,
 916                                 unsigned long *out_hwirq, unsigned int *out_type)
 917 {
 918         if (WARN_ON(intsize < 1))
 919                 return -EINVAL;
 920         *out_hwirq = intspec[0];
 921         *out_type = (intsize > 1) ? intspec[1] : IRQ_TYPE_NONE;
 922         return 0;
 923 }
 924 EXPORT_SYMBOL_GPL(irq_domain_xlate_onetwocell);
 925
 926 const struct irq_domain_ops irq_domain_simple_ops = {
 927         .xlate = irq_domain_xlate_onetwocell,
 928 };
 929 EXPORT_SYMBOL_GPL(irq_domain_simple_ops);
 930
 931 #ifdef CONFIG_OF_IRQ
 932 void irq_domain_generate_simple(const struct of_device_id *match,
 933                                 u64 phys_base, unsigned int irq_start)
 934 {
 935         struct device_node *node;
 936         pr_debug("looking for phys_base=%llx, irq_start=%i\n",
 937                 (unsigned long long) phys_base, (int) irq_start);
 938         node = of_find_matching_node_by_address(NULL, match, phys_base);
 939         if (node)
 940                 irq_domain_add_legacy(node, 32, irq_start, 0,
 941                                       &irq_domain_simple_ops, NULL);
 942 }
 943 EXPORT_SYMBOL_GPL(irq_domain_generate_simple);
 944 #endif