1/* 2 * Derived from arch/i386/kernel/irq.c 3 * Copyright (C) 1992 Linus Torvalds 4 * Adapted from arch/i386 by Gary Thomas 5 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 6 * Updated and modified by Cort Dougan <cort@fsmlabs.com> 7 * Copyright (C) 1996-2001 Cort Dougan 8 * Adapted for Power Macintosh by Paul Mackerras 9 * Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au) 10 * 11 * This program is free software; you can redistribute it and/or 12 * modify it under the terms of the GNU General Public License 13 * as published by the Free Software Foundation; either version 14 * 2 of the License, or (at your option) any later version. 15 * 16 * This file contains the code used to make IRQ descriptions in the 17 * device tree to actual irq numbers on an interrupt controller 18 * driver. 19 */ 20 21#include <linux/errno.h> 22#include <linux/list.h> 23#include <linux/module.h> 24#include <linux/of.h> 25#include <linux/of_irq.h> 26#include <linux/string.h> 27#include <linux/slab.h> 28 29/** 30 * irq_of_parse_and_map - Parse and map an interrupt into linux virq space 31 * @dev: Device node of the device whose interrupt is to be mapped 32 * @index: Index of the interrupt to map 33 * 34 * This function is a wrapper that chains of_irq_parse_one() and 35 * irq_create_of_mapping() to make things easier to callers 36 */ 37unsigned int irq_of_parse_and_map(struct device_node *dev, int index) 38{ 39 struct of_phandle_args oirq; 40 41 if (of_irq_parse_one(dev, index, &oirq)) 42 return 0; 43 44 return irq_create_of_mapping(&oirq); 45} 46EXPORT_SYMBOL_GPL(irq_of_parse_and_map); 47 48/** 49 * of_irq_find_parent - Given a device node, find its interrupt parent node 50 * @child: pointer to device node 51 * 52 * Returns a pointer to the interrupt parent node, or NULL if the interrupt 53 * parent could not be determined. 54 */ 55struct device_node *of_irq_find_parent(struct device_node *child) 56{ 57 struct device_node *p; 58 const __be32 *parp; 59 60 if (!of_node_get(child)) 61 return NULL; 62 63 do { 64 parp = of_get_property(child, "interrupt-parent", NULL); 65 if (parp == NULL) 66 p = of_get_parent(child); 67 else { 68 if (of_irq_workarounds & OF_IMAP_NO_PHANDLE) 69 p = of_node_get(of_irq_dflt_pic); 70 else 71 p = of_find_node_by_phandle(be32_to_cpup(parp)); 72 } 73 of_node_put(child); 74 child = p; 75 } while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL); 76 77 return p; 78} 79 80/** 81 * of_irq_parse_raw - Low level interrupt tree parsing 82 * @parent: the device interrupt parent 83 * @addr: address specifier (start of "reg" property of the device) in be32 format 84 * @out_irq: structure of_irq updated by this function 85 * 86 * Returns 0 on success and a negative number on error 87 * 88 * This function is a low-level interrupt tree walking function. It 89 * can be used to do a partial walk with synthetized reg and interrupts 90 * properties, for example when resolving PCI interrupts when no device 91 * node exist for the parent. It takes an interrupt specifier structure as 92 * input, walks the tree looking for any interrupt-map properties, translates 93 * the specifier for each map, and then returns the translated map. 94 */ 95int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq) 96{ 97 struct device_node *ipar, *tnode, *old = NULL, *newpar = NULL; 98 __be32 initial_match_array[MAX_PHANDLE_ARGS]; 99 const __be32 *match_array = initial_match_array; 100 const __be32 *tmp, *imap, *imask, dummy_imask[] = { [0 ... MAX_PHANDLE_ARGS] = ~0 }; 101 u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0; 102 int imaplen, match, i; 103 104#ifdef DEBUG 105 of_print_phandle_args("of_irq_parse_raw: ", out_irq); 106#endif 107 108 ipar = of_node_get(out_irq->np); 109 110 /* First get the #interrupt-cells property of the current cursor 111 * that tells us how to interpret the passed-in intspec. If there 112 * is none, we are nice and just walk up the tree 113 */ 114 do { 115 tmp = of_get_property(ipar, "#interrupt-cells", NULL); 116 if (tmp != NULL) { 117 intsize = be32_to_cpu(*tmp); 118 break; 119 } 120 tnode = ipar; 121 ipar = of_irq_find_parent(ipar); 122 of_node_put(tnode); 123 } while (ipar); 124 if (ipar == NULL) { 125 pr_debug(" -> no parent found !\n"); 126 goto fail; 127 } 128 129 pr_debug("of_irq_parse_raw: ipar=%s, size=%d\n", of_node_full_name(ipar), intsize); 130 131 if (out_irq->args_count != intsize) 132 return -EINVAL; 133 134 /* Look for this #address-cells. We have to implement the old linux 135 * trick of looking for the parent here as some device-trees rely on it 136 */ 137 old = of_node_get(ipar); 138 do { 139 tmp = of_get_property(old, "#address-cells", NULL); 140 tnode = of_get_parent(old); 141 of_node_put(old); 142 old = tnode; 143 } while (old && tmp == NULL); 144 of_node_put(old); 145 old = NULL; 146 addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp); 147 148 pr_debug(" -> addrsize=%d\n", addrsize); 149 150 /* Range check so that the temporary buffer doesn't overflow */ 151 if (WARN_ON(addrsize + intsize > MAX_PHANDLE_ARGS)) 152 goto fail; 153 154 /* Precalculate the match array - this simplifies match loop */ 155 for (i = 0; i < addrsize; i++) 156 initial_match_array[i] = addr ? addr[i] : 0; 157 for (i = 0; i < intsize; i++) 158 initial_match_array[addrsize + i] = cpu_to_be32(out_irq->args[i]); 159 160 /* Now start the actual "proper" walk of the interrupt tree */ 161 while (ipar != NULL) { 162 /* Now check if cursor is an interrupt-controller and if it is 163 * then we are done 164 */ 165 if (of_get_property(ipar, "interrupt-controller", NULL) != 166 NULL) { 167 pr_debug(" -> got it !\n"); 168 return 0; 169 } 170 171 /* 172 * interrupt-map parsing does not work without a reg 173 * property when #address-cells != 0 174 */ 175 if (addrsize && !addr) { 176 pr_debug(" -> no reg passed in when needed !\n"); 177 goto fail; 178 } 179 180 /* Now look for an interrupt-map */ 181 imap = of_get_property(ipar, "interrupt-map", &imaplen); 182 /* No interrupt map, check for an interrupt parent */ 183 if (imap == NULL) { 184 pr_debug(" -> no map, getting parent\n"); 185 newpar = of_irq_find_parent(ipar); 186 goto skiplevel; 187 } 188 imaplen /= sizeof(u32); 189 190 /* Look for a mask */ 191 imask = of_get_property(ipar, "interrupt-map-mask", NULL); 192 if (!imask) 193 imask = dummy_imask; 194 195 /* Parse interrupt-map */ 196 match = 0; 197 while (imaplen > (addrsize + intsize + 1) && !match) { 198 /* Compare specifiers */ 199 match = 1; 200 for (i = 0; i < (addrsize + intsize); i++, imaplen--) 201 match &= !((match_array[i] ^ *imap++) & imask[i]); 202 203 pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen); 204 205 /* Get the interrupt parent */ 206 if (of_irq_workarounds & OF_IMAP_NO_PHANDLE) 207 newpar = of_node_get(of_irq_dflt_pic); 208 else 209 newpar = of_find_node_by_phandle(be32_to_cpup(imap)); 210 imap++; 211 --imaplen; 212 213 /* Check if not found */ 214 if (newpar == NULL) { 215 pr_debug(" -> imap parent not found !\n"); 216 goto fail; 217 } 218 219 if (!of_device_is_available(newpar)) 220 match = 0; 221 222 /* Get #interrupt-cells and #address-cells of new 223 * parent 224 */ 225 tmp = of_get_property(newpar, "#interrupt-cells", NULL); 226 if (tmp == NULL) { 227 pr_debug(" -> parent lacks #interrupt-cells!\n"); 228 goto fail; 229 } 230 newintsize = be32_to_cpu(*tmp); 231 tmp = of_get_property(newpar, "#address-cells", NULL); 232 newaddrsize = (tmp == NULL) ? 0 : be32_to_cpu(*tmp); 233 234 pr_debug(" -> newintsize=%d, newaddrsize=%d\n", 235 newintsize, newaddrsize); 236 237 /* Check for malformed properties */ 238 if (WARN_ON(newaddrsize + newintsize > MAX_PHANDLE_ARGS)) 239 goto fail; 240 if (imaplen < (newaddrsize + newintsize)) 241 goto fail; 242 243 imap += newaddrsize + newintsize; 244 imaplen -= newaddrsize + newintsize; 245 246 pr_debug(" -> imaplen=%d\n", imaplen); 247 } 248 if (!match) 249 goto fail; 250 251 /* 252 * Successfully parsed an interrrupt-map translation; copy new 253 * interrupt specifier into the out_irq structure 254 */ 255 out_irq->np = newpar; 256 257 match_array = imap - newaddrsize - newintsize; 258 for (i = 0; i < newintsize; i++) 259 out_irq->args[i] = be32_to_cpup(imap - newintsize + i); 260 out_irq->args_count = intsize = newintsize; 261 addrsize = newaddrsize; 262 263 skiplevel: 264 /* Iterate again with new parent */ 265 pr_debug(" -> new parent: %s\n", of_node_full_name(newpar)); 266 of_node_put(ipar); 267 ipar = newpar; 268 newpar = NULL; 269 } 270 fail: 271 of_node_put(ipar); 272 of_node_put(newpar); 273 274 return -EINVAL; 275} 276EXPORT_SYMBOL_GPL(of_irq_parse_raw); 277 278/** 279 * of_irq_parse_one - Resolve an interrupt for a device 280 * @device: the device whose interrupt is to be resolved 281 * @index: index of the interrupt to resolve 282 * @out_irq: structure of_irq filled by this function 283 * 284 * This function resolves an interrupt for a node by walking the interrupt tree, 285 * finding which interrupt controller node it is attached to, and returning the 286 * interrupt specifier that can be used to retrieve a Linux IRQ number. 287 */ 288int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_args *out_irq) 289{ 290 struct device_node *p; 291 const __be32 *intspec, *tmp, *addr; 292 u32 intsize, intlen; 293 int i, res = -EINVAL; 294 295 pr_debug("of_irq_parse_one: dev=%s, index=%d\n", of_node_full_name(device), index); 296 297 /* OldWorld mac stuff is "special", handle out of line */ 298 if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC) 299 return of_irq_parse_oldworld(device, index, out_irq); 300 301 /* Get the reg property (if any) */ 302 addr = of_get_property(device, "reg", NULL); 303 304 /* Try the new-style interrupts-extended first */ 305 res = of_parse_phandle_with_args(device, "interrupts-extended", 306 "#interrupt-cells", index, out_irq); 307 if (!res) 308 return of_irq_parse_raw(addr, out_irq); 309 310 /* Get the interrupts property */ 311 intspec = of_get_property(device, "interrupts", &intlen); 312 if (intspec == NULL) 313 return -EINVAL; 314 315 intlen /= sizeof(*intspec); 316 317 pr_debug(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen); 318 319 /* Look for the interrupt parent. */ 320 p = of_irq_find_parent(device); 321 if (p == NULL) 322 return -EINVAL; 323 324 /* Get size of interrupt specifier */ 325 tmp = of_get_property(p, "#interrupt-cells", NULL); 326 if (tmp == NULL) 327 goto out; 328 intsize = be32_to_cpu(*tmp); 329 330 pr_debug(" intsize=%d intlen=%d\n", intsize, intlen); 331 332 /* Check index */ 333 if ((index + 1) * intsize > intlen) 334 goto out; 335 336 /* Copy intspec into irq structure */ 337 intspec += index * intsize; 338 out_irq->np = p; 339 out_irq->args_count = intsize; 340 for (i = 0; i < intsize; i++) 341 out_irq->args[i] = be32_to_cpup(intspec++); 342 343 /* Check if there are any interrupt-map translations to process */ 344 res = of_irq_parse_raw(addr, out_irq); 345 out: 346 of_node_put(p); 347 return res; 348} 349EXPORT_SYMBOL_GPL(of_irq_parse_one); 350 351/** 352 * of_irq_to_resource - Decode a node's IRQ and return it as a resource 353 * @dev: pointer to device tree node 354 * @index: zero-based index of the irq 355 * @r: pointer to resource structure to return result into. 356 */ 357int of_irq_to_resource(struct device_node *dev, int index, struct resource *r) 358{ 359 int irq = irq_of_parse_and_map(dev, index); 360 361 /* Only dereference the resource if both the 362 * resource and the irq are valid. */ 363 if (r && irq) { 364 const char *name = NULL; 365 366 memset(r, 0, sizeof(*r)); 367 /* 368 * Get optional "interrupt-names" property to add a name 369 * to the resource. 370 */ 371 of_property_read_string_index(dev, "interrupt-names", index, 372 &name); 373 374 r->start = r->end = irq; 375 r->flags = IORESOURCE_IRQ | irqd_get_trigger_type(irq_get_irq_data(irq)); 376 r->name = name ? name : of_node_full_name(dev); 377 } 378 379 return irq; 380} 381EXPORT_SYMBOL_GPL(of_irq_to_resource); 382 383/** 384 * of_irq_get - Decode a node's IRQ and return it as a Linux irq number 385 * @dev: pointer to device tree node 386 * @index: zero-based index of the irq 387 * 388 * Returns Linux irq number on success, or -EPROBE_DEFER if the irq domain 389 * is not yet created. 390 * 391 */ 392int of_irq_get(struct device_node *dev, int index) 393{ 394 int rc; 395 struct of_phandle_args oirq; 396 struct irq_domain *domain; 397 398 rc = of_irq_parse_one(dev, index, &oirq); 399 if (rc) 400 return rc; 401 402 domain = irq_find_host(oirq.np); 403 if (!domain) 404 return -EPROBE_DEFER; 405 406 return irq_create_of_mapping(&oirq); 407} 408 409/** 410 * of_irq_get_byname - Decode a node's IRQ and return it as a Linux irq number 411 * @dev: pointer to device tree node 412 * @name: irq name 413 * 414 * Returns Linux irq number on success, or -EPROBE_DEFER if the irq domain 415 * is not yet created, or error code in case of any other failure. 416 */ 417int of_irq_get_byname(struct device_node *dev, const char *name) 418{ 419 int index; 420 421 if (unlikely(!name)) 422 return -EINVAL; 423 424 index = of_property_match_string(dev, "interrupt-names", name); 425 if (index < 0) 426 return index; 427 428 return of_irq_get(dev, index); 429} 430 431/** 432 * of_irq_count - Count the number of IRQs a node uses 433 * @dev: pointer to device tree node 434 */ 435int of_irq_count(struct device_node *dev) 436{ 437 struct of_phandle_args irq; 438 int nr = 0; 439 440 while (of_irq_parse_one(dev, nr, &irq) == 0) 441 nr++; 442 443 return nr; 444} 445 446/** 447 * of_irq_to_resource_table - Fill in resource table with node's IRQ info 448 * @dev: pointer to device tree node 449 * @res: array of resources to fill in 450 * @nr_irqs: the number of IRQs (and upper bound for num of @res elements) 451 * 452 * Returns the size of the filled in table (up to @nr_irqs). 453 */ 454int of_irq_to_resource_table(struct device_node *dev, struct resource *res, 455 int nr_irqs) 456{ 457 int i; 458 459 for (i = 0; i < nr_irqs; i++, res++) 460 if (!of_irq_to_resource(dev, i, res)) 461 break; 462 463 return i; 464} 465EXPORT_SYMBOL_GPL(of_irq_to_resource_table); 466 467struct intc_desc { 468 struct list_head list; 469 struct device_node *dev; 470 struct device_node *interrupt_parent; 471}; 472 473/** 474 * of_irq_init - Scan and init matching interrupt controllers in DT 475 * @matches: 0 terminated array of nodes to match and init function to call 476 * 477 * This function scans the device tree for matching interrupt controller nodes, 478 * and calls their initialization functions in order with parents first. 479 */ 480void __init of_irq_init(const struct of_device_id *matches) 481{ 482 struct device_node *np, *parent = NULL; 483 struct intc_desc *desc, *temp_desc; 484 struct list_head intc_desc_list, intc_parent_list; 485 486 INIT_LIST_HEAD(&intc_desc_list); 487 INIT_LIST_HEAD(&intc_parent_list); 488 489 for_each_matching_node(np, matches) { 490 if (!of_find_property(np, "interrupt-controller", NULL) || 491 !of_device_is_available(np)) 492 continue; 493 /* 494 * Here, we allocate and populate an intc_desc with the node 495 * pointer, interrupt-parent device_node etc. 496 */ 497 desc = kzalloc(sizeof(*desc), GFP_KERNEL); 498 if (WARN_ON(!desc)) 499 goto err; 500 501 desc->dev = np; 502 desc->interrupt_parent = of_irq_find_parent(np); 503 if (desc->interrupt_parent == np) 504 desc->interrupt_parent = NULL; 505 list_add_tail(&desc->list, &intc_desc_list); 506 } 507 508 /* 509 * The root irq controller is the one without an interrupt-parent. 510 * That one goes first, followed by the controllers that reference it, 511 * followed by the ones that reference the 2nd level controllers, etc. 512 */ 513 while (!list_empty(&intc_desc_list)) { 514 /* 515 * Process all controllers with the current 'parent'. 516 * First pass will be looking for NULL as the parent. 517 * The assumption is that NULL parent means a root controller. 518 */ 519 list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) { 520 const struct of_device_id *match; 521 int ret; 522 of_irq_init_cb_t irq_init_cb; 523 524 if (desc->interrupt_parent != parent) 525 continue; 526 527 list_del(&desc->list); 528 match = of_match_node(matches, desc->dev); 529 if (WARN(!match->data, 530 "of_irq_init: no init function for %s\n", 531 match->compatible)) { 532 kfree(desc); 533 continue; 534 } 535 536 pr_debug("of_irq_init: init %s @ %p, parent %p\n", 537 match->compatible, 538 desc->dev, desc->interrupt_parent); 539 irq_init_cb = (of_irq_init_cb_t)match->data; 540 ret = irq_init_cb(desc->dev, desc->interrupt_parent); 541 if (ret) { 542 kfree(desc); 543 continue; 544 } 545 546 /* 547 * This one is now set up; add it to the parent list so 548 * its children can get processed in a subsequent pass. 549 */ 550 list_add_tail(&desc->list, &intc_parent_list); 551 } 552 553 /* Get the next pending parent that might have children */ 554 desc = list_first_entry_or_null(&intc_parent_list, 555 typeof(*desc), list); 556 if (!desc) { 557 pr_err("of_irq_init: children remain, but no parents\n"); 558 break; 559 } 560 list_del(&desc->list); 561 parent = desc->dev; 562 kfree(desc); 563 } 564 565 list_for_each_entry_safe(desc, temp_desc, &intc_parent_list, list) { 566 list_del(&desc->list); 567 kfree(desc); 568 } 569err: 570 list_for_each_entry_safe(desc, temp_desc, &intc_desc_list, list) { 571 list_del(&desc->list); 572 kfree(desc); 573 } 574} 575