1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* |
3 | * Procedures for creating, accessing and interpreting the device tree. |
4 | * |
5 | * Paul Mackerras August 1996. |
6 | * Copyright (C) 1996-2005 Paul Mackerras. |
7 | * |
8 | * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner. |
9 | * {engebret|bergner}@us.ibm.com |
10 | * |
11 | * Adapted for sparc and sparc64 by David S. Miller davem@davemloft.net |
12 | * |
13 | * Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell and |
14 | * Grant Likely. |
15 | */ |
16 | |
17 | #define pr_fmt(fmt) "OF: " fmt |
18 | |
19 | #include <linux/console.h> |
20 | #include <linux/ctype.h> |
21 | #include <linux/cpu.h> |
22 | #include <linux/module.h> |
23 | #include <linux/of.h> |
24 | #include <linux/of_device.h> |
25 | #include <linux/of_graph.h> |
26 | #include <linux/spinlock.h> |
27 | #include <linux/slab.h> |
28 | #include <linux/string.h> |
29 | #include <linux/proc_fs.h> |
30 | |
31 | #include "of_private.h" |
32 | |
33 | LIST_HEAD(aliases_lookup); |
34 | |
35 | struct device_node *of_root; |
36 | EXPORT_SYMBOL(of_root); |
37 | struct device_node *of_chosen; |
38 | EXPORT_SYMBOL(of_chosen); |
39 | struct device_node *of_aliases; |
40 | struct device_node *of_stdout; |
41 | static const char *of_stdout_options; |
42 | |
43 | struct kset *of_kset; |
44 | |
45 | /* |
46 | * Used to protect the of_aliases, to hold off addition of nodes to sysfs. |
47 | * This mutex must be held whenever modifications are being made to the |
48 | * device tree. The of_{attach,detach}_node() and |
49 | * of_{add,remove,update}_property() helpers make sure this happens. |
50 | */ |
51 | DEFINE_MUTEX(of_mutex); |
52 | |
53 | /* use when traversing tree through the child, sibling, |
54 | * or parent members of struct device_node. |
55 | */ |
56 | DEFINE_RAW_SPINLOCK(devtree_lock); |
57 | |
58 | bool of_node_name_eq(const struct device_node *np, const char *name) |
59 | { |
60 | const char *node_name; |
61 | size_t len; |
62 | |
63 | if (!np) |
64 | return false; |
65 | |
66 | node_name = kbasename(path: np->full_name); |
67 | len = strchrnul(node_name, '@') - node_name; |
68 | |
69 | return (strlen(name) == len) && (strncmp(node_name, name, len) == 0); |
70 | } |
71 | EXPORT_SYMBOL(of_node_name_eq); |
72 | |
73 | bool of_node_name_prefix(const struct device_node *np, const char *prefix) |
74 | { |
75 | if (!np) |
76 | return false; |
77 | |
78 | return strncmp(kbasename(path: np->full_name), prefix, strlen(prefix)) == 0; |
79 | } |
80 | EXPORT_SYMBOL(of_node_name_prefix); |
81 | |
82 | static bool __of_node_is_type(const struct device_node *np, const char *type) |
83 | { |
84 | const char *match = __of_get_property(np, name: "device_type" , NULL); |
85 | |
86 | return np && match && type && !strcmp(match, type); |
87 | } |
88 | |
89 | int of_bus_n_addr_cells(struct device_node *np) |
90 | { |
91 | u32 cells; |
92 | |
93 | for (; np; np = np->parent) |
94 | if (!of_property_read_u32(np, propname: "#address-cells" , out_value: &cells)) |
95 | return cells; |
96 | |
97 | /* No #address-cells property for the root node */ |
98 | return OF_ROOT_NODE_ADDR_CELLS_DEFAULT; |
99 | } |
100 | |
101 | int of_n_addr_cells(struct device_node *np) |
102 | { |
103 | if (np->parent) |
104 | np = np->parent; |
105 | |
106 | return of_bus_n_addr_cells(np); |
107 | } |
108 | EXPORT_SYMBOL(of_n_addr_cells); |
109 | |
110 | int of_bus_n_size_cells(struct device_node *np) |
111 | { |
112 | u32 cells; |
113 | |
114 | for (; np; np = np->parent) |
115 | if (!of_property_read_u32(np, propname: "#size-cells" , out_value: &cells)) |
116 | return cells; |
117 | |
118 | /* No #size-cells property for the root node */ |
119 | return OF_ROOT_NODE_SIZE_CELLS_DEFAULT; |
120 | } |
121 | |
122 | int of_n_size_cells(struct device_node *np) |
123 | { |
124 | if (np->parent) |
125 | np = np->parent; |
126 | |
127 | return of_bus_n_size_cells(np); |
128 | } |
129 | EXPORT_SYMBOL(of_n_size_cells); |
130 | |
131 | #ifdef CONFIG_NUMA |
132 | int __weak of_node_to_nid(struct device_node *np) |
133 | { |
134 | return NUMA_NO_NODE; |
135 | } |
136 | #endif |
137 | |
138 | #define OF_PHANDLE_CACHE_BITS 7 |
139 | #define OF_PHANDLE_CACHE_SZ BIT(OF_PHANDLE_CACHE_BITS) |
140 | |
141 | static struct device_node *phandle_cache[OF_PHANDLE_CACHE_SZ]; |
142 | |
143 | static u32 of_phandle_cache_hash(phandle handle) |
144 | { |
145 | return hash_32(val: handle, OF_PHANDLE_CACHE_BITS); |
146 | } |
147 | |
148 | /* |
149 | * Caller must hold devtree_lock. |
150 | */ |
151 | void __of_phandle_cache_inv_entry(phandle handle) |
152 | { |
153 | u32 handle_hash; |
154 | struct device_node *np; |
155 | |
156 | if (!handle) |
157 | return; |
158 | |
159 | handle_hash = of_phandle_cache_hash(handle); |
160 | |
161 | np = phandle_cache[handle_hash]; |
162 | if (np && handle == np->phandle) |
163 | phandle_cache[handle_hash] = NULL; |
164 | } |
165 | |
166 | void __init of_core_init(void) |
167 | { |
168 | struct device_node *np; |
169 | |
170 | of_platform_register_reconfig_notifier(); |
171 | |
172 | /* Create the kset, and register existing nodes */ |
173 | mutex_lock(&of_mutex); |
174 | of_kset = kset_create_and_add(name: "devicetree" , NULL, parent_kobj: firmware_kobj); |
175 | if (!of_kset) { |
176 | mutex_unlock(lock: &of_mutex); |
177 | pr_err("failed to register existing nodes\n" ); |
178 | return; |
179 | } |
180 | for_each_of_allnodes(np) { |
181 | __of_attach_node_sysfs(np); |
182 | if (np->phandle && !phandle_cache[of_phandle_cache_hash(handle: np->phandle)]) |
183 | phandle_cache[of_phandle_cache_hash(handle: np->phandle)] = np; |
184 | } |
185 | mutex_unlock(lock: &of_mutex); |
186 | |
187 | /* Symlink in /proc as required by userspace ABI */ |
188 | if (of_root) |
189 | proc_symlink("device-tree" , NULL, "/sys/firmware/devicetree/base" ); |
190 | } |
191 | |
192 | static struct property *__of_find_property(const struct device_node *np, |
193 | const char *name, int *lenp) |
194 | { |
195 | struct property *pp; |
196 | |
197 | if (!np) |
198 | return NULL; |
199 | |
200 | for (pp = np->properties; pp; pp = pp->next) { |
201 | if (of_prop_cmp(pp->name, name) == 0) { |
202 | if (lenp) |
203 | *lenp = pp->length; |
204 | break; |
205 | } |
206 | } |
207 | |
208 | return pp; |
209 | } |
210 | |
211 | struct property *of_find_property(const struct device_node *np, |
212 | const char *name, |
213 | int *lenp) |
214 | { |
215 | struct property *pp; |
216 | unsigned long flags; |
217 | |
218 | raw_spin_lock_irqsave(&devtree_lock, flags); |
219 | pp = __of_find_property(np, name, lenp); |
220 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
221 | |
222 | return pp; |
223 | } |
224 | EXPORT_SYMBOL(of_find_property); |
225 | |
226 | struct device_node *__of_find_all_nodes(struct device_node *prev) |
227 | { |
228 | struct device_node *np; |
229 | if (!prev) { |
230 | np = of_root; |
231 | } else if (prev->child) { |
232 | np = prev->child; |
233 | } else { |
234 | /* Walk back up looking for a sibling, or the end of the structure */ |
235 | np = prev; |
236 | while (np->parent && !np->sibling) |
237 | np = np->parent; |
238 | np = np->sibling; /* Might be null at the end of the tree */ |
239 | } |
240 | return np; |
241 | } |
242 | |
243 | /** |
244 | * of_find_all_nodes - Get next node in global list |
245 | * @prev: Previous node or NULL to start iteration |
246 | * of_node_put() will be called on it |
247 | * |
248 | * Return: A node pointer with refcount incremented, use |
249 | * of_node_put() on it when done. |
250 | */ |
251 | struct device_node *of_find_all_nodes(struct device_node *prev) |
252 | { |
253 | struct device_node *np; |
254 | unsigned long flags; |
255 | |
256 | raw_spin_lock_irqsave(&devtree_lock, flags); |
257 | np = __of_find_all_nodes(prev); |
258 | of_node_get(node: np); |
259 | of_node_put(node: prev); |
260 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
261 | return np; |
262 | } |
263 | EXPORT_SYMBOL(of_find_all_nodes); |
264 | |
265 | /* |
266 | * Find a property with a given name for a given node |
267 | * and return the value. |
268 | */ |
269 | const void *__of_get_property(const struct device_node *np, |
270 | const char *name, int *lenp) |
271 | { |
272 | struct property *pp = __of_find_property(np, name, lenp); |
273 | |
274 | return pp ? pp->value : NULL; |
275 | } |
276 | |
277 | /* |
278 | * Find a property with a given name for a given node |
279 | * and return the value. |
280 | */ |
281 | const void *of_get_property(const struct device_node *np, const char *name, |
282 | int *lenp) |
283 | { |
284 | struct property *pp = of_find_property(np, name, lenp); |
285 | |
286 | return pp ? pp->value : NULL; |
287 | } |
288 | EXPORT_SYMBOL(of_get_property); |
289 | |
290 | /** |
291 | * __of_device_is_compatible() - Check if the node matches given constraints |
292 | * @device: pointer to node |
293 | * @compat: required compatible string, NULL or "" for any match |
294 | * @type: required device_type value, NULL or "" for any match |
295 | * @name: required node name, NULL or "" for any match |
296 | * |
297 | * Checks if the given @compat, @type and @name strings match the |
298 | * properties of the given @device. A constraints can be skipped by |
299 | * passing NULL or an empty string as the constraint. |
300 | * |
301 | * Returns 0 for no match, and a positive integer on match. The return |
302 | * value is a relative score with larger values indicating better |
303 | * matches. The score is weighted for the most specific compatible value |
304 | * to get the highest score. Matching type is next, followed by matching |
305 | * name. Practically speaking, this results in the following priority |
306 | * order for matches: |
307 | * |
308 | * 1. specific compatible && type && name |
309 | * 2. specific compatible && type |
310 | * 3. specific compatible && name |
311 | * 4. specific compatible |
312 | * 5. general compatible && type && name |
313 | * 6. general compatible && type |
314 | * 7. general compatible && name |
315 | * 8. general compatible |
316 | * 9. type && name |
317 | * 10. type |
318 | * 11. name |
319 | */ |
320 | static int __of_device_is_compatible(const struct device_node *device, |
321 | const char *compat, const char *type, const char *name) |
322 | { |
323 | struct property *prop; |
324 | const char *cp; |
325 | int index = 0, score = 0; |
326 | |
327 | /* Compatible match has highest priority */ |
328 | if (compat && compat[0]) { |
329 | prop = __of_find_property(np: device, name: "compatible" , NULL); |
330 | for (cp = of_prop_next_string(prop, NULL); cp; |
331 | cp = of_prop_next_string(prop, cur: cp), index++) { |
332 | if (of_compat_cmp(cp, compat, strlen(compat)) == 0) { |
333 | score = INT_MAX/2 - (index << 2); |
334 | break; |
335 | } |
336 | } |
337 | if (!score) |
338 | return 0; |
339 | } |
340 | |
341 | /* Matching type is better than matching name */ |
342 | if (type && type[0]) { |
343 | if (!__of_node_is_type(np: device, type)) |
344 | return 0; |
345 | score += 2; |
346 | } |
347 | |
348 | /* Matching name is a bit better than not */ |
349 | if (name && name[0]) { |
350 | if (!of_node_name_eq(device, name)) |
351 | return 0; |
352 | score++; |
353 | } |
354 | |
355 | return score; |
356 | } |
357 | |
358 | /** Checks if the given "compat" string matches one of the strings in |
359 | * the device's "compatible" property |
360 | */ |
361 | int of_device_is_compatible(const struct device_node *device, |
362 | const char *compat) |
363 | { |
364 | unsigned long flags; |
365 | int res; |
366 | |
367 | raw_spin_lock_irqsave(&devtree_lock, flags); |
368 | res = __of_device_is_compatible(device, compat, NULL, NULL); |
369 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
370 | return res; |
371 | } |
372 | EXPORT_SYMBOL(of_device_is_compatible); |
373 | |
374 | /** Checks if the device is compatible with any of the entries in |
375 | * a NULL terminated array of strings. Returns the best match |
376 | * score or 0. |
377 | */ |
378 | int of_device_compatible_match(const struct device_node *device, |
379 | const char *const *compat) |
380 | { |
381 | unsigned int tmp, score = 0; |
382 | |
383 | if (!compat) |
384 | return 0; |
385 | |
386 | while (*compat) { |
387 | tmp = of_device_is_compatible(device, *compat); |
388 | if (tmp > score) |
389 | score = tmp; |
390 | compat++; |
391 | } |
392 | |
393 | return score; |
394 | } |
395 | EXPORT_SYMBOL_GPL(of_device_compatible_match); |
396 | |
397 | /** |
398 | * of_machine_compatible_match - Test root of device tree against a compatible array |
399 | * @compats: NULL terminated array of compatible strings to look for in root node's compatible property. |
400 | * |
401 | * Returns true if the root node has any of the given compatible values in its |
402 | * compatible property. |
403 | */ |
404 | bool of_machine_compatible_match(const char *const *compats) |
405 | { |
406 | struct device_node *root; |
407 | int rc = 0; |
408 | |
409 | root = of_find_node_by_path(path: "/" ); |
410 | if (root) { |
411 | rc = of_device_compatible_match(root, compats); |
412 | of_node_put(node: root); |
413 | } |
414 | |
415 | return rc != 0; |
416 | } |
417 | EXPORT_SYMBOL(of_machine_compatible_match); |
418 | |
419 | static bool __of_device_is_status(const struct device_node *device, |
420 | const char * const*strings) |
421 | { |
422 | const char *status; |
423 | int statlen; |
424 | |
425 | if (!device) |
426 | return false; |
427 | |
428 | status = __of_get_property(np: device, name: "status" , lenp: &statlen); |
429 | if (status == NULL) |
430 | return false; |
431 | |
432 | if (statlen > 0) { |
433 | while (*strings) { |
434 | unsigned int len = strlen(*strings); |
435 | |
436 | if ((*strings)[len - 1] == '-') { |
437 | if (!strncmp(status, *strings, len)) |
438 | return true; |
439 | } else { |
440 | if (!strcmp(status, *strings)) |
441 | return true; |
442 | } |
443 | strings++; |
444 | } |
445 | } |
446 | |
447 | return false; |
448 | } |
449 | |
450 | /** |
451 | * __of_device_is_available - check if a device is available for use |
452 | * |
453 | * @device: Node to check for availability, with locks already held |
454 | * |
455 | * Return: True if the status property is absent or set to "okay" or "ok", |
456 | * false otherwise |
457 | */ |
458 | static bool __of_device_is_available(const struct device_node *device) |
459 | { |
460 | static const char * const ok[] = {"okay" , "ok" , NULL}; |
461 | |
462 | if (!device) |
463 | return false; |
464 | |
465 | return !__of_get_property(np: device, name: "status" , NULL) || |
466 | __of_device_is_status(device, strings: ok); |
467 | } |
468 | |
469 | /** |
470 | * __of_device_is_reserved - check if a device is reserved |
471 | * |
472 | * @device: Node to check for availability, with locks already held |
473 | * |
474 | * Return: True if the status property is set to "reserved", false otherwise |
475 | */ |
476 | static bool __of_device_is_reserved(const struct device_node *device) |
477 | { |
478 | static const char * const reserved[] = {"reserved" , NULL}; |
479 | |
480 | return __of_device_is_status(device, strings: reserved); |
481 | } |
482 | |
483 | /** |
484 | * of_device_is_available - check if a device is available for use |
485 | * |
486 | * @device: Node to check for availability |
487 | * |
488 | * Return: True if the status property is absent or set to "okay" or "ok", |
489 | * false otherwise |
490 | */ |
491 | bool of_device_is_available(const struct device_node *device) |
492 | { |
493 | unsigned long flags; |
494 | bool res; |
495 | |
496 | raw_spin_lock_irqsave(&devtree_lock, flags); |
497 | res = __of_device_is_available(device); |
498 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
499 | return res; |
500 | |
501 | } |
502 | EXPORT_SYMBOL(of_device_is_available); |
503 | |
504 | /** |
505 | * __of_device_is_fail - check if a device has status "fail" or "fail-..." |
506 | * |
507 | * @device: Node to check status for, with locks already held |
508 | * |
509 | * Return: True if the status property is set to "fail" or "fail-..." (for any |
510 | * error code suffix), false otherwise |
511 | */ |
512 | static bool __of_device_is_fail(const struct device_node *device) |
513 | { |
514 | static const char * const fail[] = {"fail" , "fail-" , NULL}; |
515 | |
516 | return __of_device_is_status(device, strings: fail); |
517 | } |
518 | |
519 | /** |
520 | * of_device_is_big_endian - check if a device has BE registers |
521 | * |
522 | * @device: Node to check for endianness |
523 | * |
524 | * Return: True if the device has a "big-endian" property, or if the kernel |
525 | * was compiled for BE *and* the device has a "native-endian" property. |
526 | * Returns false otherwise. |
527 | * |
528 | * Callers would nominally use ioread32be/iowrite32be if |
529 | * of_device_is_big_endian() == true, or readl/writel otherwise. |
530 | */ |
531 | bool of_device_is_big_endian(const struct device_node *device) |
532 | { |
533 | if (of_property_read_bool(np: device, propname: "big-endian" )) |
534 | return true; |
535 | if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) && |
536 | of_property_read_bool(np: device, propname: "native-endian" )) |
537 | return true; |
538 | return false; |
539 | } |
540 | EXPORT_SYMBOL(of_device_is_big_endian); |
541 | |
542 | /** |
543 | * of_get_parent - Get a node's parent if any |
544 | * @node: Node to get parent |
545 | * |
546 | * Return: A node pointer with refcount incremented, use |
547 | * of_node_put() on it when done. |
548 | */ |
549 | struct device_node *of_get_parent(const struct device_node *node) |
550 | { |
551 | struct device_node *np; |
552 | unsigned long flags; |
553 | |
554 | if (!node) |
555 | return NULL; |
556 | |
557 | raw_spin_lock_irqsave(&devtree_lock, flags); |
558 | np = of_node_get(node: node->parent); |
559 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
560 | return np; |
561 | } |
562 | EXPORT_SYMBOL(of_get_parent); |
563 | |
564 | /** |
565 | * of_get_next_parent - Iterate to a node's parent |
566 | * @node: Node to get parent of |
567 | * |
568 | * This is like of_get_parent() except that it drops the |
569 | * refcount on the passed node, making it suitable for iterating |
570 | * through a node's parents. |
571 | * |
572 | * Return: A node pointer with refcount incremented, use |
573 | * of_node_put() on it when done. |
574 | */ |
575 | struct device_node *of_get_next_parent(struct device_node *node) |
576 | { |
577 | struct device_node *parent; |
578 | unsigned long flags; |
579 | |
580 | if (!node) |
581 | return NULL; |
582 | |
583 | raw_spin_lock_irqsave(&devtree_lock, flags); |
584 | parent = of_node_get(node: node->parent); |
585 | of_node_put(node); |
586 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
587 | return parent; |
588 | } |
589 | EXPORT_SYMBOL(of_get_next_parent); |
590 | |
591 | static struct device_node *__of_get_next_child(const struct device_node *node, |
592 | struct device_node *prev) |
593 | { |
594 | struct device_node *next; |
595 | |
596 | if (!node) |
597 | return NULL; |
598 | |
599 | next = prev ? prev->sibling : node->child; |
600 | of_node_get(node: next); |
601 | of_node_put(node: prev); |
602 | return next; |
603 | } |
604 | #define __for_each_child_of_node(parent, child) \ |
605 | for (child = __of_get_next_child(parent, NULL); child != NULL; \ |
606 | child = __of_get_next_child(parent, child)) |
607 | |
608 | /** |
609 | * of_get_next_child - Iterate a node childs |
610 | * @node: parent node |
611 | * @prev: previous child of the parent node, or NULL to get first |
612 | * |
613 | * Return: A node pointer with refcount incremented, use of_node_put() on |
614 | * it when done. Returns NULL when prev is the last child. Decrements the |
615 | * refcount of prev. |
616 | */ |
617 | struct device_node *of_get_next_child(const struct device_node *node, |
618 | struct device_node *prev) |
619 | { |
620 | struct device_node *next; |
621 | unsigned long flags; |
622 | |
623 | raw_spin_lock_irqsave(&devtree_lock, flags); |
624 | next = __of_get_next_child(node, prev); |
625 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
626 | return next; |
627 | } |
628 | EXPORT_SYMBOL(of_get_next_child); |
629 | |
630 | static struct device_node *of_get_next_status_child(const struct device_node *node, |
631 | struct device_node *prev, |
632 | bool (*checker)(const struct device_node *)) |
633 | { |
634 | struct device_node *next; |
635 | unsigned long flags; |
636 | |
637 | if (!node) |
638 | return NULL; |
639 | |
640 | raw_spin_lock_irqsave(&devtree_lock, flags); |
641 | next = prev ? prev->sibling : node->child; |
642 | for (; next; next = next->sibling) { |
643 | if (!checker(next)) |
644 | continue; |
645 | if (of_node_get(node: next)) |
646 | break; |
647 | } |
648 | of_node_put(node: prev); |
649 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
650 | return next; |
651 | } |
652 | |
653 | /** |
654 | * of_get_next_available_child - Find the next available child node |
655 | * @node: parent node |
656 | * @prev: previous child of the parent node, or NULL to get first |
657 | * |
658 | * This function is like of_get_next_child(), except that it |
659 | * automatically skips any disabled nodes (i.e. status = "disabled"). |
660 | */ |
661 | struct device_node *of_get_next_available_child(const struct device_node *node, |
662 | struct device_node *prev) |
663 | { |
664 | return of_get_next_status_child(node, prev, checker: __of_device_is_available); |
665 | } |
666 | EXPORT_SYMBOL(of_get_next_available_child); |
667 | |
668 | /** |
669 | * of_get_next_reserved_child - Find the next reserved child node |
670 | * @node: parent node |
671 | * @prev: previous child of the parent node, or NULL to get first |
672 | * |
673 | * This function is like of_get_next_child(), except that it |
674 | * automatically skips any disabled nodes (i.e. status = "disabled"). |
675 | */ |
676 | struct device_node *of_get_next_reserved_child(const struct device_node *node, |
677 | struct device_node *prev) |
678 | { |
679 | return of_get_next_status_child(node, prev, checker: __of_device_is_reserved); |
680 | } |
681 | EXPORT_SYMBOL(of_get_next_reserved_child); |
682 | |
683 | /** |
684 | * of_get_next_cpu_node - Iterate on cpu nodes |
685 | * @prev: previous child of the /cpus node, or NULL to get first |
686 | * |
687 | * Unusable CPUs (those with the status property set to "fail" or "fail-...") |
688 | * will be skipped. |
689 | * |
690 | * Return: A cpu node pointer with refcount incremented, use of_node_put() |
691 | * on it when done. Returns NULL when prev is the last child. Decrements |
692 | * the refcount of prev. |
693 | */ |
694 | struct device_node *of_get_next_cpu_node(struct device_node *prev) |
695 | { |
696 | struct device_node *next = NULL; |
697 | unsigned long flags; |
698 | struct device_node *node; |
699 | |
700 | if (!prev) |
701 | node = of_find_node_by_path(path: "/cpus" ); |
702 | |
703 | raw_spin_lock_irqsave(&devtree_lock, flags); |
704 | if (prev) |
705 | next = prev->sibling; |
706 | else if (node) { |
707 | next = node->child; |
708 | of_node_put(node); |
709 | } |
710 | for (; next; next = next->sibling) { |
711 | if (__of_device_is_fail(device: next)) |
712 | continue; |
713 | if (!(of_node_name_eq(next, "cpu" ) || |
714 | __of_node_is_type(np: next, type: "cpu" ))) |
715 | continue; |
716 | if (of_node_get(node: next)) |
717 | break; |
718 | } |
719 | of_node_put(node: prev); |
720 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
721 | return next; |
722 | } |
723 | EXPORT_SYMBOL(of_get_next_cpu_node); |
724 | |
725 | /** |
726 | * of_get_compatible_child - Find compatible child node |
727 | * @parent: parent node |
728 | * @compatible: compatible string |
729 | * |
730 | * Lookup child node whose compatible property contains the given compatible |
731 | * string. |
732 | * |
733 | * Return: a node pointer with refcount incremented, use of_node_put() on it |
734 | * when done; or NULL if not found. |
735 | */ |
736 | struct device_node *of_get_compatible_child(const struct device_node *parent, |
737 | const char *compatible) |
738 | { |
739 | struct device_node *child; |
740 | |
741 | for_each_child_of_node(parent, child) { |
742 | if (of_device_is_compatible(child, compatible)) |
743 | break; |
744 | } |
745 | |
746 | return child; |
747 | } |
748 | EXPORT_SYMBOL(of_get_compatible_child); |
749 | |
750 | /** |
751 | * of_get_child_by_name - Find the child node by name for a given parent |
752 | * @node: parent node |
753 | * @name: child name to look for. |
754 | * |
755 | * This function looks for child node for given matching name |
756 | * |
757 | * Return: A node pointer if found, with refcount incremented, use |
758 | * of_node_put() on it when done. |
759 | * Returns NULL if node is not found. |
760 | */ |
761 | struct device_node *of_get_child_by_name(const struct device_node *node, |
762 | const char *name) |
763 | { |
764 | struct device_node *child; |
765 | |
766 | for_each_child_of_node(node, child) |
767 | if (of_node_name_eq(child, name)) |
768 | break; |
769 | return child; |
770 | } |
771 | EXPORT_SYMBOL(of_get_child_by_name); |
772 | |
773 | struct device_node *__of_find_node_by_path(struct device_node *parent, |
774 | const char *path) |
775 | { |
776 | struct device_node *child; |
777 | int len; |
778 | |
779 | len = strcspn(path, "/:" ); |
780 | if (!len) |
781 | return NULL; |
782 | |
783 | __for_each_child_of_node(parent, child) { |
784 | const char *name = kbasename(path: child->full_name); |
785 | if (strncmp(path, name, len) == 0 && (strlen(name) == len)) |
786 | return child; |
787 | } |
788 | return NULL; |
789 | } |
790 | |
791 | struct device_node *__of_find_node_by_full_path(struct device_node *node, |
792 | const char *path) |
793 | { |
794 | const char *separator = strchr(path, ':'); |
795 | |
796 | while (node && *path == '/') { |
797 | struct device_node *tmp = node; |
798 | |
799 | path++; /* Increment past '/' delimiter */ |
800 | node = __of_find_node_by_path(parent: node, path); |
801 | of_node_put(node: tmp); |
802 | path = strchrnul(path, '/'); |
803 | if (separator && separator < path) |
804 | break; |
805 | } |
806 | return node; |
807 | } |
808 | |
809 | /** |
810 | * of_find_node_opts_by_path - Find a node matching a full OF path |
811 | * @path: Either the full path to match, or if the path does not |
812 | * start with '/', the name of a property of the /aliases |
813 | * node (an alias). In the case of an alias, the node |
814 | * matching the alias' value will be returned. |
815 | * @opts: Address of a pointer into which to store the start of |
816 | * an options string appended to the end of the path with |
817 | * a ':' separator. |
818 | * |
819 | * Valid paths: |
820 | * * /foo/bar Full path |
821 | * * foo Valid alias |
822 | * * foo/bar Valid alias + relative path |
823 | * |
824 | * Return: A node pointer with refcount incremented, use |
825 | * of_node_put() on it when done. |
826 | */ |
827 | struct device_node *of_find_node_opts_by_path(const char *path, const char **opts) |
828 | { |
829 | struct device_node *np = NULL; |
830 | struct property *pp; |
831 | unsigned long flags; |
832 | const char *separator = strchr(path, ':'); |
833 | |
834 | if (opts) |
835 | *opts = separator ? separator + 1 : NULL; |
836 | |
837 | if (strcmp(path, "/" ) == 0) |
838 | return of_node_get(node: of_root); |
839 | |
840 | /* The path could begin with an alias */ |
841 | if (*path != '/') { |
842 | int len; |
843 | const char *p = separator; |
844 | |
845 | if (!p) |
846 | p = strchrnul(path, '/'); |
847 | len = p - path; |
848 | |
849 | /* of_aliases must not be NULL */ |
850 | if (!of_aliases) |
851 | return NULL; |
852 | |
853 | for_each_property_of_node(of_aliases, pp) { |
854 | if (strlen(pp->name) == len && !strncmp(pp->name, path, len)) { |
855 | np = of_find_node_by_path(path: pp->value); |
856 | break; |
857 | } |
858 | } |
859 | if (!np) |
860 | return NULL; |
861 | path = p; |
862 | } |
863 | |
864 | /* Step down the tree matching path components */ |
865 | raw_spin_lock_irqsave(&devtree_lock, flags); |
866 | if (!np) |
867 | np = of_node_get(node: of_root); |
868 | np = __of_find_node_by_full_path(node: np, path); |
869 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
870 | return np; |
871 | } |
872 | EXPORT_SYMBOL(of_find_node_opts_by_path); |
873 | |
874 | /** |
875 | * of_find_node_by_name - Find a node by its "name" property |
876 | * @from: The node to start searching from or NULL; the node |
877 | * you pass will not be searched, only the next one |
878 | * will. Typically, you pass what the previous call |
879 | * returned. of_node_put() will be called on @from. |
880 | * @name: The name string to match against |
881 | * |
882 | * Return: A node pointer with refcount incremented, use |
883 | * of_node_put() on it when done. |
884 | */ |
885 | struct device_node *of_find_node_by_name(struct device_node *from, |
886 | const char *name) |
887 | { |
888 | struct device_node *np; |
889 | unsigned long flags; |
890 | |
891 | raw_spin_lock_irqsave(&devtree_lock, flags); |
892 | for_each_of_allnodes_from(from, np) |
893 | if (of_node_name_eq(np, name) && of_node_get(node: np)) |
894 | break; |
895 | of_node_put(node: from); |
896 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
897 | return np; |
898 | } |
899 | EXPORT_SYMBOL(of_find_node_by_name); |
900 | |
901 | /** |
902 | * of_find_node_by_type - Find a node by its "device_type" property |
903 | * @from: The node to start searching from, or NULL to start searching |
904 | * the entire device tree. The node you pass will not be |
905 | * searched, only the next one will; typically, you pass |
906 | * what the previous call returned. of_node_put() will be |
907 | * called on from for you. |
908 | * @type: The type string to match against |
909 | * |
910 | * Return: A node pointer with refcount incremented, use |
911 | * of_node_put() on it when done. |
912 | */ |
913 | struct device_node *of_find_node_by_type(struct device_node *from, |
914 | const char *type) |
915 | { |
916 | struct device_node *np; |
917 | unsigned long flags; |
918 | |
919 | raw_spin_lock_irqsave(&devtree_lock, flags); |
920 | for_each_of_allnodes_from(from, np) |
921 | if (__of_node_is_type(np, type) && of_node_get(node: np)) |
922 | break; |
923 | of_node_put(node: from); |
924 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
925 | return np; |
926 | } |
927 | EXPORT_SYMBOL(of_find_node_by_type); |
928 | |
929 | /** |
930 | * of_find_compatible_node - Find a node based on type and one of the |
931 | * tokens in its "compatible" property |
932 | * @from: The node to start searching from or NULL, the node |
933 | * you pass will not be searched, only the next one |
934 | * will; typically, you pass what the previous call |
935 | * returned. of_node_put() will be called on it |
936 | * @type: The type string to match "device_type" or NULL to ignore |
937 | * @compatible: The string to match to one of the tokens in the device |
938 | * "compatible" list. |
939 | * |
940 | * Return: A node pointer with refcount incremented, use |
941 | * of_node_put() on it when done. |
942 | */ |
943 | struct device_node *of_find_compatible_node(struct device_node *from, |
944 | const char *type, const char *compatible) |
945 | { |
946 | struct device_node *np; |
947 | unsigned long flags; |
948 | |
949 | raw_spin_lock_irqsave(&devtree_lock, flags); |
950 | for_each_of_allnodes_from(from, np) |
951 | if (__of_device_is_compatible(device: np, compat: compatible, type, NULL) && |
952 | of_node_get(node: np)) |
953 | break; |
954 | of_node_put(node: from); |
955 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
956 | return np; |
957 | } |
958 | EXPORT_SYMBOL(of_find_compatible_node); |
959 | |
960 | /** |
961 | * of_find_node_with_property - Find a node which has a property with |
962 | * the given name. |
963 | * @from: The node to start searching from or NULL, the node |
964 | * you pass will not be searched, only the next one |
965 | * will; typically, you pass what the previous call |
966 | * returned. of_node_put() will be called on it |
967 | * @prop_name: The name of the property to look for. |
968 | * |
969 | * Return: A node pointer with refcount incremented, use |
970 | * of_node_put() on it when done. |
971 | */ |
972 | struct device_node *of_find_node_with_property(struct device_node *from, |
973 | const char *prop_name) |
974 | { |
975 | struct device_node *np; |
976 | struct property *pp; |
977 | unsigned long flags; |
978 | |
979 | raw_spin_lock_irqsave(&devtree_lock, flags); |
980 | for_each_of_allnodes_from(from, np) { |
981 | for (pp = np->properties; pp; pp = pp->next) { |
982 | if (of_prop_cmp(pp->name, prop_name) == 0) { |
983 | of_node_get(node: np); |
984 | goto out; |
985 | } |
986 | } |
987 | } |
988 | out: |
989 | of_node_put(node: from); |
990 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
991 | return np; |
992 | } |
993 | EXPORT_SYMBOL(of_find_node_with_property); |
994 | |
995 | static |
996 | const struct of_device_id *__of_match_node(const struct of_device_id *matches, |
997 | const struct device_node *node) |
998 | { |
999 | const struct of_device_id *best_match = NULL; |
1000 | int score, best_score = 0; |
1001 | |
1002 | if (!matches) |
1003 | return NULL; |
1004 | |
1005 | for (; matches->name[0] || matches->type[0] || matches->compatible[0]; matches++) { |
1006 | score = __of_device_is_compatible(device: node, compat: matches->compatible, |
1007 | type: matches->type, name: matches->name); |
1008 | if (score > best_score) { |
1009 | best_match = matches; |
1010 | best_score = score; |
1011 | } |
1012 | } |
1013 | |
1014 | return best_match; |
1015 | } |
1016 | |
1017 | /** |
1018 | * of_match_node - Tell if a device_node has a matching of_match structure |
1019 | * @matches: array of of device match structures to search in |
1020 | * @node: the of device structure to match against |
1021 | * |
1022 | * Low level utility function used by device matching. |
1023 | */ |
1024 | const struct of_device_id *of_match_node(const struct of_device_id *matches, |
1025 | const struct device_node *node) |
1026 | { |
1027 | const struct of_device_id *match; |
1028 | unsigned long flags; |
1029 | |
1030 | raw_spin_lock_irqsave(&devtree_lock, flags); |
1031 | match = __of_match_node(matches, node); |
1032 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
1033 | return match; |
1034 | } |
1035 | EXPORT_SYMBOL(of_match_node); |
1036 | |
1037 | /** |
1038 | * of_find_matching_node_and_match - Find a node based on an of_device_id |
1039 | * match table. |
1040 | * @from: The node to start searching from or NULL, the node |
1041 | * you pass will not be searched, only the next one |
1042 | * will; typically, you pass what the previous call |
1043 | * returned. of_node_put() will be called on it |
1044 | * @matches: array of of device match structures to search in |
1045 | * @match: Updated to point at the matches entry which matched |
1046 | * |
1047 | * Return: A node pointer with refcount incremented, use |
1048 | * of_node_put() on it when done. |
1049 | */ |
1050 | struct device_node *of_find_matching_node_and_match(struct device_node *from, |
1051 | const struct of_device_id *matches, |
1052 | const struct of_device_id **match) |
1053 | { |
1054 | struct device_node *np; |
1055 | const struct of_device_id *m; |
1056 | unsigned long flags; |
1057 | |
1058 | if (match) |
1059 | *match = NULL; |
1060 | |
1061 | raw_spin_lock_irqsave(&devtree_lock, flags); |
1062 | for_each_of_allnodes_from(from, np) { |
1063 | m = __of_match_node(matches, node: np); |
1064 | if (m && of_node_get(node: np)) { |
1065 | if (match) |
1066 | *match = m; |
1067 | break; |
1068 | } |
1069 | } |
1070 | of_node_put(node: from); |
1071 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
1072 | return np; |
1073 | } |
1074 | EXPORT_SYMBOL(of_find_matching_node_and_match); |
1075 | |
1076 | /** |
1077 | * of_alias_from_compatible - Lookup appropriate alias for a device node |
1078 | * depending on compatible |
1079 | * @node: pointer to a device tree node |
1080 | * @alias: Pointer to buffer that alias value will be copied into |
1081 | * @len: Length of alias value |
1082 | * |
1083 | * Based on the value of the compatible property, this routine will attempt |
1084 | * to choose an appropriate alias value for a particular device tree node. |
1085 | * It does this by stripping the manufacturer prefix (as delimited by a ',') |
1086 | * from the first entry in the compatible list property. |
1087 | * |
1088 | * Note: The matching on just the "product" side of the compatible is a relic |
1089 | * from I2C and SPI. Please do not add any new user. |
1090 | * |
1091 | * Return: This routine returns 0 on success, <0 on failure. |
1092 | */ |
1093 | int of_alias_from_compatible(const struct device_node *node, char *alias, int len) |
1094 | { |
1095 | const char *compatible, *p; |
1096 | int cplen; |
1097 | |
1098 | compatible = of_get_property(node, "compatible" , &cplen); |
1099 | if (!compatible || strlen(compatible) > cplen) |
1100 | return -ENODEV; |
1101 | p = strchr(compatible, ','); |
1102 | strscpy(alias, p ? p + 1 : compatible, len); |
1103 | return 0; |
1104 | } |
1105 | EXPORT_SYMBOL_GPL(of_alias_from_compatible); |
1106 | |
1107 | /** |
1108 | * of_find_node_by_phandle - Find a node given a phandle |
1109 | * @handle: phandle of the node to find |
1110 | * |
1111 | * Return: A node pointer with refcount incremented, use |
1112 | * of_node_put() on it when done. |
1113 | */ |
1114 | struct device_node *of_find_node_by_phandle(phandle handle) |
1115 | { |
1116 | struct device_node *np = NULL; |
1117 | unsigned long flags; |
1118 | u32 handle_hash; |
1119 | |
1120 | if (!handle) |
1121 | return NULL; |
1122 | |
1123 | handle_hash = of_phandle_cache_hash(handle); |
1124 | |
1125 | raw_spin_lock_irqsave(&devtree_lock, flags); |
1126 | |
1127 | if (phandle_cache[handle_hash] && |
1128 | handle == phandle_cache[handle_hash]->phandle) |
1129 | np = phandle_cache[handle_hash]; |
1130 | |
1131 | if (!np) { |
1132 | for_each_of_allnodes(np) |
1133 | if (np->phandle == handle && |
1134 | !of_node_check_flag(n: np, OF_DETACHED)) { |
1135 | phandle_cache[handle_hash] = np; |
1136 | break; |
1137 | } |
1138 | } |
1139 | |
1140 | of_node_get(node: np); |
1141 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
1142 | return np; |
1143 | } |
1144 | EXPORT_SYMBOL(of_find_node_by_phandle); |
1145 | |
1146 | void of_print_phandle_args(const char *msg, const struct of_phandle_args *args) |
1147 | { |
1148 | int i; |
1149 | printk("%s %pOF" , msg, args->np); |
1150 | for (i = 0; i < args->args_count; i++) { |
1151 | const char delim = i ? ',' : ':'; |
1152 | |
1153 | pr_cont("%c%08x" , delim, args->args[i]); |
1154 | } |
1155 | pr_cont("\n" ); |
1156 | } |
1157 | |
1158 | int of_phandle_iterator_init(struct of_phandle_iterator *it, |
1159 | const struct device_node *np, |
1160 | const char *list_name, |
1161 | const char *cells_name, |
1162 | int cell_count) |
1163 | { |
1164 | const __be32 *list; |
1165 | int size; |
1166 | |
1167 | memset(it, 0, sizeof(*it)); |
1168 | |
1169 | /* |
1170 | * one of cell_count or cells_name must be provided to determine the |
1171 | * argument length. |
1172 | */ |
1173 | if (cell_count < 0 && !cells_name) |
1174 | return -EINVAL; |
1175 | |
1176 | list = of_get_property(np, list_name, &size); |
1177 | if (!list) |
1178 | return -ENOENT; |
1179 | |
1180 | it->cells_name = cells_name; |
1181 | it->cell_count = cell_count; |
1182 | it->parent = np; |
1183 | it->list_end = list + size / sizeof(*list); |
1184 | it->phandle_end = list; |
1185 | it->cur = list; |
1186 | |
1187 | return 0; |
1188 | } |
1189 | EXPORT_SYMBOL_GPL(of_phandle_iterator_init); |
1190 | |
1191 | int of_phandle_iterator_next(struct of_phandle_iterator *it) |
1192 | { |
1193 | uint32_t count = 0; |
1194 | |
1195 | if (it->node) { |
1196 | of_node_put(node: it->node); |
1197 | it->node = NULL; |
1198 | } |
1199 | |
1200 | if (!it->cur || it->phandle_end >= it->list_end) |
1201 | return -ENOENT; |
1202 | |
1203 | it->cur = it->phandle_end; |
1204 | |
1205 | /* If phandle is 0, then it is an empty entry with no arguments. */ |
1206 | it->phandle = be32_to_cpup(p: it->cur++); |
1207 | |
1208 | if (it->phandle) { |
1209 | |
1210 | /* |
1211 | * Find the provider node and parse the #*-cells property to |
1212 | * determine the argument length. |
1213 | */ |
1214 | it->node = of_find_node_by_phandle(it->phandle); |
1215 | |
1216 | if (it->cells_name) { |
1217 | if (!it->node) { |
1218 | pr_err("%pOF: could not find phandle %d\n" , |
1219 | it->parent, it->phandle); |
1220 | goto err; |
1221 | } |
1222 | |
1223 | if (of_property_read_u32(np: it->node, propname: it->cells_name, |
1224 | out_value: &count)) { |
1225 | /* |
1226 | * If both cell_count and cells_name is given, |
1227 | * fall back to cell_count in absence |
1228 | * of the cells_name property |
1229 | */ |
1230 | if (it->cell_count >= 0) { |
1231 | count = it->cell_count; |
1232 | } else { |
1233 | pr_err("%pOF: could not get %s for %pOF\n" , |
1234 | it->parent, |
1235 | it->cells_name, |
1236 | it->node); |
1237 | goto err; |
1238 | } |
1239 | } |
1240 | } else { |
1241 | count = it->cell_count; |
1242 | } |
1243 | |
1244 | /* |
1245 | * Make sure that the arguments actually fit in the remaining |
1246 | * property data length |
1247 | */ |
1248 | if (it->cur + count > it->list_end) { |
1249 | if (it->cells_name) |
1250 | pr_err("%pOF: %s = %d found %td\n" , |
1251 | it->parent, it->cells_name, |
1252 | count, it->list_end - it->cur); |
1253 | else |
1254 | pr_err("%pOF: phandle %s needs %d, found %td\n" , |
1255 | it->parent, of_node_full_name(it->node), |
1256 | count, it->list_end - it->cur); |
1257 | goto err; |
1258 | } |
1259 | } |
1260 | |
1261 | it->phandle_end = it->cur + count; |
1262 | it->cur_count = count; |
1263 | |
1264 | return 0; |
1265 | |
1266 | err: |
1267 | if (it->node) { |
1268 | of_node_put(node: it->node); |
1269 | it->node = NULL; |
1270 | } |
1271 | |
1272 | return -EINVAL; |
1273 | } |
1274 | EXPORT_SYMBOL_GPL(of_phandle_iterator_next); |
1275 | |
1276 | int of_phandle_iterator_args(struct of_phandle_iterator *it, |
1277 | uint32_t *args, |
1278 | int size) |
1279 | { |
1280 | int i, count; |
1281 | |
1282 | count = it->cur_count; |
1283 | |
1284 | if (WARN_ON(size < count)) |
1285 | count = size; |
1286 | |
1287 | for (i = 0; i < count; i++) |
1288 | args[i] = be32_to_cpup(p: it->cur++); |
1289 | |
1290 | return count; |
1291 | } |
1292 | |
1293 | int __of_parse_phandle_with_args(const struct device_node *np, |
1294 | const char *list_name, |
1295 | const char *cells_name, |
1296 | int cell_count, int index, |
1297 | struct of_phandle_args *out_args) |
1298 | { |
1299 | struct of_phandle_iterator it; |
1300 | int rc, cur_index = 0; |
1301 | |
1302 | if (index < 0) |
1303 | return -EINVAL; |
1304 | |
1305 | /* Loop over the phandles until all the requested entry is found */ |
1306 | of_for_each_phandle(&it, rc, np, list_name, cells_name, cell_count) { |
1307 | /* |
1308 | * All of the error cases bail out of the loop, so at |
1309 | * this point, the parsing is successful. If the requested |
1310 | * index matches, then fill the out_args structure and return, |
1311 | * or return -ENOENT for an empty entry. |
1312 | */ |
1313 | rc = -ENOENT; |
1314 | if (cur_index == index) { |
1315 | if (!it.phandle) |
1316 | goto err; |
1317 | |
1318 | if (out_args) { |
1319 | int c; |
1320 | |
1321 | c = of_phandle_iterator_args(it: &it, |
1322 | args: out_args->args, |
1323 | MAX_PHANDLE_ARGS); |
1324 | out_args->np = it.node; |
1325 | out_args->args_count = c; |
1326 | } else { |
1327 | of_node_put(node: it.node); |
1328 | } |
1329 | |
1330 | /* Found it! return success */ |
1331 | return 0; |
1332 | } |
1333 | |
1334 | cur_index++; |
1335 | } |
1336 | |
1337 | /* |
1338 | * Unlock node before returning result; will be one of: |
1339 | * -ENOENT : index is for empty phandle |
1340 | * -EINVAL : parsing error on data |
1341 | */ |
1342 | |
1343 | err: |
1344 | of_node_put(node: it.node); |
1345 | return rc; |
1346 | } |
1347 | EXPORT_SYMBOL(__of_parse_phandle_with_args); |
1348 | |
1349 | /** |
1350 | * of_parse_phandle_with_args_map() - Find a node pointed by phandle in a list and remap it |
1351 | * @np: pointer to a device tree node containing a list |
1352 | * @list_name: property name that contains a list |
1353 | * @stem_name: stem of property names that specify phandles' arguments count |
1354 | * @index: index of a phandle to parse out |
1355 | * @out_args: optional pointer to output arguments structure (will be filled) |
1356 | * |
1357 | * This function is useful to parse lists of phandles and their arguments. |
1358 | * Returns 0 on success and fills out_args, on error returns appropriate errno |
1359 | * value. The difference between this function and of_parse_phandle_with_args() |
1360 | * is that this API remaps a phandle if the node the phandle points to has |
1361 | * a <@stem_name>-map property. |
1362 | * |
1363 | * Caller is responsible to call of_node_put() on the returned out_args->np |
1364 | * pointer. |
1365 | * |
1366 | * Example:: |
1367 | * |
1368 | * phandle1: node1 { |
1369 | * #list-cells = <2>; |
1370 | * }; |
1371 | * |
1372 | * phandle2: node2 { |
1373 | * #list-cells = <1>; |
1374 | * }; |
1375 | * |
1376 | * phandle3: node3 { |
1377 | * #list-cells = <1>; |
1378 | * list-map = <0 &phandle2 3>, |
1379 | * <1 &phandle2 2>, |
1380 | * <2 &phandle1 5 1>; |
1381 | * list-map-mask = <0x3>; |
1382 | * }; |
1383 | * |
1384 | * node4 { |
1385 | * list = <&phandle1 1 2 &phandle3 0>; |
1386 | * }; |
1387 | * |
1388 | * To get a device_node of the ``node2`` node you may call this: |
1389 | * of_parse_phandle_with_args(node4, "list", "list", 1, &args); |
1390 | */ |
1391 | int of_parse_phandle_with_args_map(const struct device_node *np, |
1392 | const char *list_name, |
1393 | const char *stem_name, |
1394 | int index, struct of_phandle_args *out_args) |
1395 | { |
1396 | char *cells_name, *map_name = NULL, *mask_name = NULL; |
1397 | char *pass_name = NULL; |
1398 | struct device_node *cur, *new = NULL; |
1399 | const __be32 *map, *mask, *pass; |
1400 | static const __be32 dummy_mask[] = { [0 ... MAX_PHANDLE_ARGS] = cpu_to_be32(~0) }; |
1401 | static const __be32 dummy_pass[] = { [0 ... MAX_PHANDLE_ARGS] = cpu_to_be32(0) }; |
1402 | __be32 initial_match_array[MAX_PHANDLE_ARGS]; |
1403 | const __be32 *match_array = initial_match_array; |
1404 | int i, ret, map_len, match; |
1405 | u32 list_size, new_size; |
1406 | |
1407 | if (index < 0) |
1408 | return -EINVAL; |
1409 | |
1410 | cells_name = kasprintf(GFP_KERNEL, fmt: "#%s-cells" , stem_name); |
1411 | if (!cells_name) |
1412 | return -ENOMEM; |
1413 | |
1414 | ret = -ENOMEM; |
1415 | map_name = kasprintf(GFP_KERNEL, fmt: "%s-map" , stem_name); |
1416 | if (!map_name) |
1417 | goto free; |
1418 | |
1419 | mask_name = kasprintf(GFP_KERNEL, fmt: "%s-map-mask" , stem_name); |
1420 | if (!mask_name) |
1421 | goto free; |
1422 | |
1423 | pass_name = kasprintf(GFP_KERNEL, fmt: "%s-map-pass-thru" , stem_name); |
1424 | if (!pass_name) |
1425 | goto free; |
1426 | |
1427 | ret = __of_parse_phandle_with_args(np, list_name, cells_name, -1, index, |
1428 | out_args); |
1429 | if (ret) |
1430 | goto free; |
1431 | |
1432 | /* Get the #<list>-cells property */ |
1433 | cur = out_args->np; |
1434 | ret = of_property_read_u32(np: cur, propname: cells_name, out_value: &list_size); |
1435 | if (ret < 0) |
1436 | goto put; |
1437 | |
1438 | /* Precalculate the match array - this simplifies match loop */ |
1439 | for (i = 0; i < list_size; i++) |
1440 | initial_match_array[i] = cpu_to_be32(out_args->args[i]); |
1441 | |
1442 | ret = -EINVAL; |
1443 | while (cur) { |
1444 | /* Get the <list>-map property */ |
1445 | map = of_get_property(cur, map_name, &map_len); |
1446 | if (!map) { |
1447 | ret = 0; |
1448 | goto free; |
1449 | } |
1450 | map_len /= sizeof(u32); |
1451 | |
1452 | /* Get the <list>-map-mask property (optional) */ |
1453 | mask = of_get_property(cur, mask_name, NULL); |
1454 | if (!mask) |
1455 | mask = dummy_mask; |
1456 | /* Iterate through <list>-map property */ |
1457 | match = 0; |
1458 | while (map_len > (list_size + 1) && !match) { |
1459 | /* Compare specifiers */ |
1460 | match = 1; |
1461 | for (i = 0; i < list_size; i++, map_len--) |
1462 | match &= !((match_array[i] ^ *map++) & mask[i]); |
1463 | |
1464 | of_node_put(node: new); |
1465 | new = of_find_node_by_phandle(be32_to_cpup(p: map)); |
1466 | map++; |
1467 | map_len--; |
1468 | |
1469 | /* Check if not found */ |
1470 | if (!new) |
1471 | goto put; |
1472 | |
1473 | if (!of_device_is_available(new)) |
1474 | match = 0; |
1475 | |
1476 | ret = of_property_read_u32(np: new, propname: cells_name, out_value: &new_size); |
1477 | if (ret) |
1478 | goto put; |
1479 | |
1480 | /* Check for malformed properties */ |
1481 | if (WARN_ON(new_size > MAX_PHANDLE_ARGS)) |
1482 | goto put; |
1483 | if (map_len < new_size) |
1484 | goto put; |
1485 | |
1486 | /* Move forward by new node's #<list>-cells amount */ |
1487 | map += new_size; |
1488 | map_len -= new_size; |
1489 | } |
1490 | if (!match) |
1491 | goto put; |
1492 | |
1493 | /* Get the <list>-map-pass-thru property (optional) */ |
1494 | pass = of_get_property(cur, pass_name, NULL); |
1495 | if (!pass) |
1496 | pass = dummy_pass; |
1497 | |
1498 | /* |
1499 | * Successfully parsed a <list>-map translation; copy new |
1500 | * specifier into the out_args structure, keeping the |
1501 | * bits specified in <list>-map-pass-thru. |
1502 | */ |
1503 | match_array = map - new_size; |
1504 | for (i = 0; i < new_size; i++) { |
1505 | __be32 val = *(map - new_size + i); |
1506 | |
1507 | if (i < list_size) { |
1508 | val &= ~pass[i]; |
1509 | val |= cpu_to_be32(out_args->args[i]) & pass[i]; |
1510 | } |
1511 | |
1512 | out_args->args[i] = be32_to_cpu(val); |
1513 | } |
1514 | out_args->args_count = list_size = new_size; |
1515 | /* Iterate again with new provider */ |
1516 | out_args->np = new; |
1517 | of_node_put(node: cur); |
1518 | cur = new; |
1519 | new = NULL; |
1520 | } |
1521 | put: |
1522 | of_node_put(node: cur); |
1523 | of_node_put(node: new); |
1524 | free: |
1525 | kfree(objp: mask_name); |
1526 | kfree(objp: map_name); |
1527 | kfree(objp: cells_name); |
1528 | kfree(objp: pass_name); |
1529 | |
1530 | return ret; |
1531 | } |
1532 | EXPORT_SYMBOL(of_parse_phandle_with_args_map); |
1533 | |
1534 | /** |
1535 | * of_count_phandle_with_args() - Find the number of phandles references in a property |
1536 | * @np: pointer to a device tree node containing a list |
1537 | * @list_name: property name that contains a list |
1538 | * @cells_name: property name that specifies phandles' arguments count |
1539 | * |
1540 | * Return: The number of phandle + argument tuples within a property. It |
1541 | * is a typical pattern to encode a list of phandle and variable |
1542 | * arguments into a single property. The number of arguments is encoded |
1543 | * by a property in the phandle-target node. For example, a gpios |
1544 | * property would contain a list of GPIO specifies consisting of a |
1545 | * phandle and 1 or more arguments. The number of arguments are |
1546 | * determined by the #gpio-cells property in the node pointed to by the |
1547 | * phandle. |
1548 | */ |
1549 | int of_count_phandle_with_args(const struct device_node *np, const char *list_name, |
1550 | const char *cells_name) |
1551 | { |
1552 | struct of_phandle_iterator it; |
1553 | int rc, cur_index = 0; |
1554 | |
1555 | /* |
1556 | * If cells_name is NULL we assume a cell count of 0. This makes |
1557 | * counting the phandles trivial as each 32bit word in the list is a |
1558 | * phandle and no arguments are to consider. So we don't iterate through |
1559 | * the list but just use the length to determine the phandle count. |
1560 | */ |
1561 | if (!cells_name) { |
1562 | const __be32 *list; |
1563 | int size; |
1564 | |
1565 | list = of_get_property(np, list_name, &size); |
1566 | if (!list) |
1567 | return -ENOENT; |
1568 | |
1569 | return size / sizeof(*list); |
1570 | } |
1571 | |
1572 | rc = of_phandle_iterator_init(&it, np, list_name, cells_name, -1); |
1573 | if (rc) |
1574 | return rc; |
1575 | |
1576 | while ((rc = of_phandle_iterator_next(&it)) == 0) |
1577 | cur_index += 1; |
1578 | |
1579 | if (rc != -ENOENT) |
1580 | return rc; |
1581 | |
1582 | return cur_index; |
1583 | } |
1584 | EXPORT_SYMBOL(of_count_phandle_with_args); |
1585 | |
1586 | static struct property *__of_remove_property_from_list(struct property **list, struct property *prop) |
1587 | { |
1588 | struct property **next; |
1589 | |
1590 | for (next = list; *next; next = &(*next)->next) { |
1591 | if (*next == prop) { |
1592 | *next = prop->next; |
1593 | prop->next = NULL; |
1594 | return prop; |
1595 | } |
1596 | } |
1597 | return NULL; |
1598 | } |
1599 | |
1600 | /** |
1601 | * __of_add_property - Add a property to a node without lock operations |
1602 | * @np: Caller's Device Node |
1603 | * @prop: Property to add |
1604 | */ |
1605 | int __of_add_property(struct device_node *np, struct property *prop) |
1606 | { |
1607 | int rc = 0; |
1608 | unsigned long flags; |
1609 | struct property **next; |
1610 | |
1611 | raw_spin_lock_irqsave(&devtree_lock, flags); |
1612 | |
1613 | __of_remove_property_from_list(list: &np->deadprops, prop); |
1614 | |
1615 | prop->next = NULL; |
1616 | next = &np->properties; |
1617 | while (*next) { |
1618 | if (strcmp(prop->name, (*next)->name) == 0) { |
1619 | /* duplicate ! don't insert it */ |
1620 | rc = -EEXIST; |
1621 | goto out_unlock; |
1622 | } |
1623 | next = &(*next)->next; |
1624 | } |
1625 | *next = prop; |
1626 | |
1627 | out_unlock: |
1628 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
1629 | if (rc) |
1630 | return rc; |
1631 | |
1632 | __of_add_property_sysfs(np, pp: prop); |
1633 | return 0; |
1634 | } |
1635 | |
1636 | /** |
1637 | * of_add_property - Add a property to a node |
1638 | * @np: Caller's Device Node |
1639 | * @prop: Property to add |
1640 | */ |
1641 | int of_add_property(struct device_node *np, struct property *prop) |
1642 | { |
1643 | int rc; |
1644 | |
1645 | mutex_lock(&of_mutex); |
1646 | rc = __of_add_property(np, prop); |
1647 | mutex_unlock(lock: &of_mutex); |
1648 | |
1649 | if (!rc) |
1650 | of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop, NULL); |
1651 | |
1652 | return rc; |
1653 | } |
1654 | EXPORT_SYMBOL_GPL(of_add_property); |
1655 | |
1656 | int __of_remove_property(struct device_node *np, struct property *prop) |
1657 | { |
1658 | unsigned long flags; |
1659 | int rc = -ENODEV; |
1660 | |
1661 | raw_spin_lock_irqsave(&devtree_lock, flags); |
1662 | |
1663 | if (__of_remove_property_from_list(list: &np->properties, prop)) { |
1664 | /* Found the property, add it to deadprops list */ |
1665 | prop->next = np->deadprops; |
1666 | np->deadprops = prop; |
1667 | rc = 0; |
1668 | } |
1669 | |
1670 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
1671 | if (rc) |
1672 | return rc; |
1673 | |
1674 | __of_remove_property_sysfs(np, prop); |
1675 | return 0; |
1676 | } |
1677 | |
1678 | /** |
1679 | * of_remove_property - Remove a property from a node. |
1680 | * @np: Caller's Device Node |
1681 | * @prop: Property to remove |
1682 | * |
1683 | * Note that we don't actually remove it, since we have given out |
1684 | * who-knows-how-many pointers to the data using get-property. |
1685 | * Instead we just move the property to the "dead properties" |
1686 | * list, so it won't be found any more. |
1687 | */ |
1688 | int of_remove_property(struct device_node *np, struct property *prop) |
1689 | { |
1690 | int rc; |
1691 | |
1692 | if (!prop) |
1693 | return -ENODEV; |
1694 | |
1695 | mutex_lock(&of_mutex); |
1696 | rc = __of_remove_property(np, prop); |
1697 | mutex_unlock(lock: &of_mutex); |
1698 | |
1699 | if (!rc) |
1700 | of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop, NULL); |
1701 | |
1702 | return rc; |
1703 | } |
1704 | EXPORT_SYMBOL_GPL(of_remove_property); |
1705 | |
1706 | int __of_update_property(struct device_node *np, struct property *newprop, |
1707 | struct property **oldpropp) |
1708 | { |
1709 | struct property **next, *oldprop; |
1710 | unsigned long flags; |
1711 | |
1712 | raw_spin_lock_irqsave(&devtree_lock, flags); |
1713 | |
1714 | __of_remove_property_from_list(list: &np->deadprops, prop: newprop); |
1715 | |
1716 | for (next = &np->properties; *next; next = &(*next)->next) { |
1717 | if (of_prop_cmp((*next)->name, newprop->name) == 0) |
1718 | break; |
1719 | } |
1720 | *oldpropp = oldprop = *next; |
1721 | |
1722 | if (oldprop) { |
1723 | /* replace the node */ |
1724 | newprop->next = oldprop->next; |
1725 | *next = newprop; |
1726 | oldprop->next = np->deadprops; |
1727 | np->deadprops = oldprop; |
1728 | } else { |
1729 | /* new node */ |
1730 | newprop->next = NULL; |
1731 | *next = newprop; |
1732 | } |
1733 | |
1734 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
1735 | |
1736 | __of_update_property_sysfs(np, newprop, oldprop); |
1737 | |
1738 | return 0; |
1739 | } |
1740 | |
1741 | /* |
1742 | * of_update_property - Update a property in a node, if the property does |
1743 | * not exist, add it. |
1744 | * |
1745 | * Note that we don't actually remove it, since we have given out |
1746 | * who-knows-how-many pointers to the data using get-property. |
1747 | * Instead we just move the property to the "dead properties" list, |
1748 | * and add the new property to the property list |
1749 | */ |
1750 | int of_update_property(struct device_node *np, struct property *newprop) |
1751 | { |
1752 | struct property *oldprop; |
1753 | int rc; |
1754 | |
1755 | if (!newprop->name) |
1756 | return -EINVAL; |
1757 | |
1758 | mutex_lock(&of_mutex); |
1759 | rc = __of_update_property(np, newprop, oldpropp: &oldprop); |
1760 | mutex_unlock(lock: &of_mutex); |
1761 | |
1762 | if (!rc) |
1763 | of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, prop: newprop, old_prop: oldprop); |
1764 | |
1765 | return rc; |
1766 | } |
1767 | |
1768 | static void of_alias_add(struct alias_prop *ap, struct device_node *np, |
1769 | int id, const char *stem, int stem_len) |
1770 | { |
1771 | ap->np = np; |
1772 | ap->id = id; |
1773 | strscpy(ap->stem, stem, stem_len + 1); |
1774 | list_add_tail(new: &ap->link, head: &aliases_lookup); |
1775 | pr_debug("adding DT alias:%s: stem=%s id=%i node=%pOF\n" , |
1776 | ap->alias, ap->stem, ap->id, np); |
1777 | } |
1778 | |
1779 | /** |
1780 | * of_alias_scan - Scan all properties of the 'aliases' node |
1781 | * @dt_alloc: An allocator that provides a virtual address to memory |
1782 | * for storing the resulting tree |
1783 | * |
1784 | * The function scans all the properties of the 'aliases' node and populates |
1785 | * the global lookup table with the properties. It returns the |
1786 | * number of alias properties found, or an error code in case of failure. |
1787 | */ |
1788 | void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align)) |
1789 | { |
1790 | struct property *pp; |
1791 | |
1792 | of_aliases = of_find_node_by_path(path: "/aliases" ); |
1793 | of_chosen = of_find_node_by_path(path: "/chosen" ); |
1794 | if (of_chosen == NULL) |
1795 | of_chosen = of_find_node_by_path(path: "/chosen@0" ); |
1796 | |
1797 | if (of_chosen) { |
1798 | /* linux,stdout-path and /aliases/stdout are for legacy compatibility */ |
1799 | const char *name = NULL; |
1800 | |
1801 | if (of_property_read_string(np: of_chosen, propname: "stdout-path" , out_string: &name)) |
1802 | of_property_read_string(np: of_chosen, propname: "linux,stdout-path" , |
1803 | out_string: &name); |
1804 | if (IS_ENABLED(CONFIG_PPC) && !name) |
1805 | of_property_read_string(np: of_aliases, propname: "stdout" , out_string: &name); |
1806 | if (name) |
1807 | of_stdout = of_find_node_opts_by_path(name, &of_stdout_options); |
1808 | if (of_stdout) |
1809 | of_stdout->fwnode.flags |= FWNODE_FLAG_BEST_EFFORT; |
1810 | } |
1811 | |
1812 | if (!of_aliases) |
1813 | return; |
1814 | |
1815 | for_each_property_of_node(of_aliases, pp) { |
1816 | const char *start = pp->name; |
1817 | const char *end = start + strlen(start); |
1818 | struct device_node *np; |
1819 | struct alias_prop *ap; |
1820 | int id, len; |
1821 | |
1822 | /* Skip those we do not want to proceed */ |
1823 | if (!strcmp(pp->name, "name" ) || |
1824 | !strcmp(pp->name, "phandle" ) || |
1825 | !strcmp(pp->name, "linux,phandle" )) |
1826 | continue; |
1827 | |
1828 | np = of_find_node_by_path(path: pp->value); |
1829 | if (!np) |
1830 | continue; |
1831 | |
1832 | /* walk the alias backwards to extract the id and work out |
1833 | * the 'stem' string */ |
1834 | while (isdigit(c: *(end-1)) && end > start) |
1835 | end--; |
1836 | len = end - start; |
1837 | |
1838 | if (kstrtoint(s: end, base: 10, res: &id) < 0) |
1839 | continue; |
1840 | |
1841 | /* Allocate an alias_prop with enough space for the stem */ |
1842 | ap = dt_alloc(sizeof(*ap) + len + 1, __alignof__(*ap)); |
1843 | if (!ap) |
1844 | continue; |
1845 | memset(ap, 0, sizeof(*ap) + len + 1); |
1846 | ap->alias = start; |
1847 | of_alias_add(ap, np, id, stem: start, stem_len: len); |
1848 | } |
1849 | } |
1850 | |
1851 | /** |
1852 | * of_alias_get_id - Get alias id for the given device_node |
1853 | * @np: Pointer to the given device_node |
1854 | * @stem: Alias stem of the given device_node |
1855 | * |
1856 | * The function travels the lookup table to get the alias id for the given |
1857 | * device_node and alias stem. |
1858 | * |
1859 | * Return: The alias id if found. |
1860 | */ |
1861 | int of_alias_get_id(struct device_node *np, const char *stem) |
1862 | { |
1863 | struct alias_prop *app; |
1864 | int id = -ENODEV; |
1865 | |
1866 | mutex_lock(&of_mutex); |
1867 | list_for_each_entry(app, &aliases_lookup, link) { |
1868 | if (strcmp(app->stem, stem) != 0) |
1869 | continue; |
1870 | |
1871 | if (np == app->np) { |
1872 | id = app->id; |
1873 | break; |
1874 | } |
1875 | } |
1876 | mutex_unlock(lock: &of_mutex); |
1877 | |
1878 | return id; |
1879 | } |
1880 | EXPORT_SYMBOL_GPL(of_alias_get_id); |
1881 | |
1882 | /** |
1883 | * of_alias_get_highest_id - Get highest alias id for the given stem |
1884 | * @stem: Alias stem to be examined |
1885 | * |
1886 | * The function travels the lookup table to get the highest alias id for the |
1887 | * given alias stem. It returns the alias id if found. |
1888 | */ |
1889 | int of_alias_get_highest_id(const char *stem) |
1890 | { |
1891 | struct alias_prop *app; |
1892 | int id = -ENODEV; |
1893 | |
1894 | mutex_lock(&of_mutex); |
1895 | list_for_each_entry(app, &aliases_lookup, link) { |
1896 | if (strcmp(app->stem, stem) != 0) |
1897 | continue; |
1898 | |
1899 | if (app->id > id) |
1900 | id = app->id; |
1901 | } |
1902 | mutex_unlock(lock: &of_mutex); |
1903 | |
1904 | return id; |
1905 | } |
1906 | EXPORT_SYMBOL_GPL(of_alias_get_highest_id); |
1907 | |
1908 | /** |
1909 | * of_console_check() - Test and setup console for DT setup |
1910 | * @dn: Pointer to device node |
1911 | * @name: Name to use for preferred console without index. ex. "ttyS" |
1912 | * @index: Index to use for preferred console. |
1913 | * |
1914 | * Check if the given device node matches the stdout-path property in the |
1915 | * /chosen node. If it does then register it as the preferred console. |
1916 | * |
1917 | * Return: TRUE if console successfully setup. Otherwise return FALSE. |
1918 | */ |
1919 | bool of_console_check(struct device_node *dn, char *name, int index) |
1920 | { |
1921 | if (!dn || dn != of_stdout || console_set_on_cmdline) |
1922 | return false; |
1923 | |
1924 | /* |
1925 | * XXX: cast `options' to char pointer to suppress complication |
1926 | * warnings: printk, UART and console drivers expect char pointer. |
1927 | */ |
1928 | return !add_preferred_console(name, idx: index, options: (char *)of_stdout_options); |
1929 | } |
1930 | EXPORT_SYMBOL_GPL(of_console_check); |
1931 | |
1932 | /** |
1933 | * of_find_next_cache_node - Find a node's subsidiary cache |
1934 | * @np: node of type "cpu" or "cache" |
1935 | * |
1936 | * Return: A node pointer with refcount incremented, use |
1937 | * of_node_put() on it when done. Caller should hold a reference |
1938 | * to np. |
1939 | */ |
1940 | struct device_node *of_find_next_cache_node(const struct device_node *np) |
1941 | { |
1942 | struct device_node *child, *cache_node; |
1943 | |
1944 | cache_node = of_parse_phandle(np, phandle_name: "l2-cache" , index: 0); |
1945 | if (!cache_node) |
1946 | cache_node = of_parse_phandle(np, phandle_name: "next-level-cache" , index: 0); |
1947 | |
1948 | if (cache_node) |
1949 | return cache_node; |
1950 | |
1951 | /* OF on pmac has nodes instead of properties named "l2-cache" |
1952 | * beneath CPU nodes. |
1953 | */ |
1954 | if (IS_ENABLED(CONFIG_PPC_PMAC) && of_node_is_type(np, type: "cpu" )) |
1955 | for_each_child_of_node(np, child) |
1956 | if (of_node_is_type(np: child, type: "cache" )) |
1957 | return child; |
1958 | |
1959 | return NULL; |
1960 | } |
1961 | |
1962 | /** |
1963 | * of_find_last_cache_level - Find the level at which the last cache is |
1964 | * present for the given logical cpu |
1965 | * |
1966 | * @cpu: cpu number(logical index) for which the last cache level is needed |
1967 | * |
1968 | * Return: The level at which the last cache is present. It is exactly |
1969 | * same as the total number of cache levels for the given logical cpu. |
1970 | */ |
1971 | int of_find_last_cache_level(unsigned int cpu) |
1972 | { |
1973 | u32 cache_level = 0; |
1974 | struct device_node *prev = NULL, *np = of_cpu_device_node_get(cpu); |
1975 | |
1976 | while (np) { |
1977 | of_node_put(node: prev); |
1978 | prev = np; |
1979 | np = of_find_next_cache_node(np); |
1980 | } |
1981 | |
1982 | of_property_read_u32(np: prev, propname: "cache-level" , out_value: &cache_level); |
1983 | of_node_put(node: prev); |
1984 | |
1985 | return cache_level; |
1986 | } |
1987 | |
1988 | /** |
1989 | * of_map_id - Translate an ID through a downstream mapping. |
1990 | * @np: root complex device node. |
1991 | * @id: device ID to map. |
1992 | * @map_name: property name of the map to use. |
1993 | * @map_mask_name: optional property name of the mask to use. |
1994 | * @target: optional pointer to a target device node. |
1995 | * @id_out: optional pointer to receive the translated ID. |
1996 | * |
1997 | * Given a device ID, look up the appropriate implementation-defined |
1998 | * platform ID and/or the target device which receives transactions on that |
1999 | * ID, as per the "iommu-map" and "msi-map" bindings. Either of @target or |
2000 | * @id_out may be NULL if only the other is required. If @target points to |
2001 | * a non-NULL device node pointer, only entries targeting that node will be |
2002 | * matched; if it points to a NULL value, it will receive the device node of |
2003 | * the first matching target phandle, with a reference held. |
2004 | * |
2005 | * Return: 0 on success or a standard error code on failure. |
2006 | */ |
2007 | int of_map_id(struct device_node *np, u32 id, |
2008 | const char *map_name, const char *map_mask_name, |
2009 | struct device_node **target, u32 *id_out) |
2010 | { |
2011 | u32 map_mask, masked_id; |
2012 | int map_len; |
2013 | const __be32 *map = NULL; |
2014 | |
2015 | if (!np || !map_name || (!target && !id_out)) |
2016 | return -EINVAL; |
2017 | |
2018 | map = of_get_property(np, map_name, &map_len); |
2019 | if (!map) { |
2020 | if (target) |
2021 | return -ENODEV; |
2022 | /* Otherwise, no map implies no translation */ |
2023 | *id_out = id; |
2024 | return 0; |
2025 | } |
2026 | |
2027 | if (!map_len || map_len % (4 * sizeof(*map))) { |
2028 | pr_err("%pOF: Error: Bad %s length: %d\n" , np, |
2029 | map_name, map_len); |
2030 | return -EINVAL; |
2031 | } |
2032 | |
2033 | /* The default is to select all bits. */ |
2034 | map_mask = 0xffffffff; |
2035 | |
2036 | /* |
2037 | * Can be overridden by "{iommu,msi}-map-mask" property. |
2038 | * If of_property_read_u32() fails, the default is used. |
2039 | */ |
2040 | if (map_mask_name) |
2041 | of_property_read_u32(np, propname: map_mask_name, out_value: &map_mask); |
2042 | |
2043 | masked_id = map_mask & id; |
2044 | for ( ; map_len > 0; map_len -= 4 * sizeof(*map), map += 4) { |
2045 | struct device_node *phandle_node; |
2046 | u32 id_base = be32_to_cpup(p: map + 0); |
2047 | u32 phandle = be32_to_cpup(p: map + 1); |
2048 | u32 out_base = be32_to_cpup(p: map + 2); |
2049 | u32 id_len = be32_to_cpup(p: map + 3); |
2050 | |
2051 | if (id_base & ~map_mask) { |
2052 | pr_err("%pOF: Invalid %s translation - %s-mask (0x%x) ignores id-base (0x%x)\n" , |
2053 | np, map_name, map_name, |
2054 | map_mask, id_base); |
2055 | return -EFAULT; |
2056 | } |
2057 | |
2058 | if (masked_id < id_base || masked_id >= id_base + id_len) |
2059 | continue; |
2060 | |
2061 | phandle_node = of_find_node_by_phandle(phandle); |
2062 | if (!phandle_node) |
2063 | return -ENODEV; |
2064 | |
2065 | if (target) { |
2066 | if (*target) |
2067 | of_node_put(node: phandle_node); |
2068 | else |
2069 | *target = phandle_node; |
2070 | |
2071 | if (*target != phandle_node) |
2072 | continue; |
2073 | } |
2074 | |
2075 | if (id_out) |
2076 | *id_out = masked_id - id_base + out_base; |
2077 | |
2078 | pr_debug("%pOF: %s, using mask %08x, id-base: %08x, out-base: %08x, length: %08x, id: %08x -> %08x\n" , |
2079 | np, map_name, map_mask, id_base, out_base, |
2080 | id_len, id, masked_id - id_base + out_base); |
2081 | return 0; |
2082 | } |
2083 | |
2084 | pr_info("%pOF: no %s translation for id 0x%x on %pOF\n" , np, map_name, |
2085 | id, target && *target ? *target : NULL); |
2086 | |
2087 | /* Bypasses translation */ |
2088 | if (id_out) |
2089 | *id_out = id; |
2090 | return 0; |
2091 | } |
2092 | EXPORT_SYMBOL_GPL(of_map_id); |
2093 | |