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/bitmap.h>
20#include <linux/console.h>
21#include <linux/ctype.h>
22#include <linux/cpu.h>
23#include <linux/module.h>
24#include <linux/of.h>
25#include <linux/of_device.h>
26#include <linux/of_graph.h>
27#include <linux/spinlock.h>
28#include <linux/slab.h>
29#include <linux/string.h>
30#include <linux/proc_fs.h>
31
32#include "of_private.h"
33
34LIST_HEAD(aliases_lookup);
35
36struct device_node *of_root;
37EXPORT_SYMBOL(of_root);
38struct device_node *of_chosen;
39struct device_node *of_aliases;
40struct device_node *of_stdout;
41static const char *of_stdout_options;
42
43struct 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 */
51DEFINE_MUTEX(of_mutex);
52
53/* use when traversing tree through the child, sibling,
54 * or parent members of struct device_node.
55 */
56DEFINE_RAW_SPINLOCK(devtree_lock);
57
58bool 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(np->full_name);
67 len = strchrnul(node_name, '@') - node_name;
68
69 return (strlen(name) == len) && (strncmp(node_name, name, len) == 0);
70}
71EXPORT_SYMBOL(of_node_name_eq);
72
73bool of_node_name_prefix(const struct device_node *np, const char *prefix)
74{
75 if (!np)
76 return false;
77
78 return strncmp(kbasename(np->full_name), prefix, strlen(prefix)) == 0;
79}
80EXPORT_SYMBOL(of_node_name_prefix);
81
82static bool __of_node_is_type(const struct device_node *np, const char *type)
83{
84 const char *match = __of_get_property(np, "device_type", NULL);
85
86 return np && match && type && !strcmp(match, type);
87}
88
89int of_n_addr_cells(struct device_node *np)
90{
91 u32 cells;
92
93 do {
94 if (np->parent)
95 np = np->parent;
96 if (!of_property_read_u32(np, "#address-cells", &cells))
97 return cells;
98 } while (np->parent);
99 /* No #address-cells property for the root node */
100 return OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
101}
102EXPORT_SYMBOL(of_n_addr_cells);
103
104int of_n_size_cells(struct device_node *np)
105{
106 u32 cells;
107
108 do {
109 if (np->parent)
110 np = np->parent;
111 if (!of_property_read_u32(np, "#size-cells", &cells))
112 return cells;
113 } while (np->parent);
114 /* No #size-cells property for the root node */
115 return OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
116}
117EXPORT_SYMBOL(of_n_size_cells);
118
119#ifdef CONFIG_NUMA
120int __weak of_node_to_nid(struct device_node *np)
121{
122 return NUMA_NO_NODE;
123}
124#endif
125
126/*
127 * Assumptions behind phandle_cache implementation:
128 * - phandle property values are in a contiguous range of 1..n
129 *
130 * If the assumptions do not hold, then
131 * - the phandle lookup overhead reduction provided by the cache
132 * will likely be less
133 */
134
135static struct device_node **phandle_cache;
136static u32 phandle_cache_mask;
137
138/*
139 * Caller must hold devtree_lock.
140 */
141static void __of_free_phandle_cache(void)
142{
143 u32 cache_entries = phandle_cache_mask + 1;
144 u32 k;
145
146 if (!phandle_cache)
147 return;
148
149 for (k = 0; k < cache_entries; k++)
150 of_node_put(phandle_cache[k]);
151
152 kfree(phandle_cache);
153 phandle_cache = NULL;
154}
155
156int of_free_phandle_cache(void)
157{
158 unsigned long flags;
159
160 raw_spin_lock_irqsave(&devtree_lock, flags);
161
162 __of_free_phandle_cache();
163
164 raw_spin_unlock_irqrestore(&devtree_lock, flags);
165
166 return 0;
167}
168#if !defined(CONFIG_MODULES)
169late_initcall_sync(of_free_phandle_cache);
170#endif
171
172/*
173 * Caller must hold devtree_lock.
174 */
175void __of_free_phandle_cache_entry(phandle handle)
176{
177 phandle masked_handle;
178 struct device_node *np;
179
180 if (!handle)
181 return;
182
183 masked_handle = handle & phandle_cache_mask;
184
185 if (phandle_cache) {
186 np = phandle_cache[masked_handle];
187 if (np && handle == np->phandle) {
188 of_node_put(np);
189 phandle_cache[masked_handle] = NULL;
190 }
191 }
192}
193
194void of_populate_phandle_cache(void)
195{
196 unsigned long flags;
197 u32 cache_entries;
198 struct device_node *np;
199 u32 phandles = 0;
200
201 raw_spin_lock_irqsave(&devtree_lock, flags);
202
203 __of_free_phandle_cache();
204
205 for_each_of_allnodes(np)
206 if (np->phandle && np->phandle != OF_PHANDLE_ILLEGAL)
207 phandles++;
208
209 if (!phandles)
210 goto out;
211
212 cache_entries = roundup_pow_of_two(phandles);
213 phandle_cache_mask = cache_entries - 1;
214
215 phandle_cache = kcalloc(cache_entries, sizeof(*phandle_cache),
216 GFP_ATOMIC);
217 if (!phandle_cache)
218 goto out;
219
220 for_each_of_allnodes(np)
221 if (np->phandle && np->phandle != OF_PHANDLE_ILLEGAL) {
222 of_node_get(np);
223 phandle_cache[np->phandle & phandle_cache_mask] = np;
224 }
225
226out:
227 raw_spin_unlock_irqrestore(&devtree_lock, flags);
228}
229
230void __init of_core_init(void)
231{
232 struct device_node *np;
233
234 of_populate_phandle_cache();
235
236 /* Create the kset, and register existing nodes */
237 mutex_lock(&of_mutex);
238 of_kset = kset_create_and_add("devicetree", NULL, firmware_kobj);
239 if (!of_kset) {
240 mutex_unlock(&of_mutex);
241 pr_err("failed to register existing nodes\n");
242 return;
243 }
244 for_each_of_allnodes(np)
245 __of_attach_node_sysfs(np);
246 mutex_unlock(&of_mutex);
247
248 /* Symlink in /proc as required by userspace ABI */
249 if (of_root)
250 proc_symlink("device-tree", NULL, "/sys/firmware/devicetree/base");
251}
252
253static struct property *__of_find_property(const struct device_node *np,
254 const char *name, int *lenp)
255{
256 struct property *pp;
257
258 if (!np)
259 return NULL;
260
261 for (pp = np->properties; pp; pp = pp->next) {
262 if (of_prop_cmp(pp->name, name) == 0) {
263 if (lenp)
264 *lenp = pp->length;
265 break;
266 }
267 }
268
269 return pp;
270}
271
272struct property *of_find_property(const struct device_node *np,
273 const char *name,
274 int *lenp)
275{
276 struct property *pp;
277 unsigned long flags;
278
279 raw_spin_lock_irqsave(&devtree_lock, flags);
280 pp = __of_find_property(np, name, lenp);
281 raw_spin_unlock_irqrestore(&devtree_lock, flags);
282
283 return pp;
284}
285EXPORT_SYMBOL(of_find_property);
286
287struct device_node *__of_find_all_nodes(struct device_node *prev)
288{
289 struct device_node *np;
290 if (!prev) {
291 np = of_root;
292 } else if (prev->child) {
293 np = prev->child;
294 } else {
295 /* Walk back up looking for a sibling, or the end of the structure */
296 np = prev;
297 while (np->parent && !np->sibling)
298 np = np->parent;
299 np = np->sibling; /* Might be null at the end of the tree */
300 }
301 return np;
302}
303
304/**
305 * of_find_all_nodes - Get next node in global list
306 * @prev: Previous node or NULL to start iteration
307 * of_node_put() will be called on it
308 *
309 * Returns a node pointer with refcount incremented, use
310 * of_node_put() on it when done.
311 */
312struct device_node *of_find_all_nodes(struct device_node *prev)
313{
314 struct device_node *np;
315 unsigned long flags;
316
317 raw_spin_lock_irqsave(&devtree_lock, flags);
318 np = __of_find_all_nodes(prev);
319 of_node_get(np);
320 of_node_put(prev);
321 raw_spin_unlock_irqrestore(&devtree_lock, flags);
322 return np;
323}
324EXPORT_SYMBOL(of_find_all_nodes);
325
326/*
327 * Find a property with a given name for a given node
328 * and return the value.
329 */
330const void *__of_get_property(const struct device_node *np,
331 const char *name, int *lenp)
332{
333 struct property *pp = __of_find_property(np, name, lenp);
334
335 return pp ? pp->value : NULL;
336}
337
338/*
339 * Find a property with a given name for a given node
340 * and return the value.
341 */
342const void *of_get_property(const struct device_node *np, const char *name,
343 int *lenp)
344{
345 struct property *pp = of_find_property(np, name, lenp);
346
347 return pp ? pp->value : NULL;
348}
349EXPORT_SYMBOL(of_get_property);
350
351/*
352 * arch_match_cpu_phys_id - Match the given logical CPU and physical id
353 *
354 * @cpu: logical cpu index of a core/thread
355 * @phys_id: physical identifier of a core/thread
356 *
357 * CPU logical to physical index mapping is architecture specific.
358 * However this __weak function provides a default match of physical
359 * id to logical cpu index. phys_id provided here is usually values read
360 * from the device tree which must match the hardware internal registers.
361 *
362 * Returns true if the physical identifier and the logical cpu index
363 * correspond to the same core/thread, false otherwise.
364 */
365bool __weak arch_match_cpu_phys_id(int cpu, u64 phys_id)
366{
367 return (u32)phys_id == cpu;
368}
369
370/**
371 * Checks if the given "prop_name" property holds the physical id of the
372 * core/thread corresponding to the logical cpu 'cpu'. If 'thread' is not
373 * NULL, local thread number within the core is returned in it.
374 */
375static bool __of_find_n_match_cpu_property(struct device_node *cpun,
376 const char *prop_name, int cpu, unsigned int *thread)
377{
378 const __be32 *cell;
379 int ac, prop_len, tid;
380 u64 hwid;
381
382 ac = of_n_addr_cells(cpun);
383 cell = of_get_property(cpun, prop_name, &prop_len);
384 if (!cell && !ac && arch_match_cpu_phys_id(cpu, 0))
385 return true;
386 if (!cell || !ac)
387 return false;
388 prop_len /= sizeof(*cell) * ac;
389 for (tid = 0; tid < prop_len; tid++) {
390 hwid = of_read_number(cell, ac);
391 if (arch_match_cpu_phys_id(cpu, hwid)) {
392 if (thread)
393 *thread = tid;
394 return true;
395 }
396 cell += ac;
397 }
398 return false;
399}
400
401/*
402 * arch_find_n_match_cpu_physical_id - See if the given device node is
403 * for the cpu corresponding to logical cpu 'cpu'. Return true if so,
404 * else false. If 'thread' is non-NULL, the local thread number within the
405 * core is returned in it.
406 */
407bool __weak arch_find_n_match_cpu_physical_id(struct device_node *cpun,
408 int cpu, unsigned int *thread)
409{
410 /* Check for non-standard "ibm,ppc-interrupt-server#s" property
411 * for thread ids on PowerPC. If it doesn't exist fallback to
412 * standard "reg" property.
413 */
414 if (IS_ENABLED(CONFIG_PPC) &&
415 __of_find_n_match_cpu_property(cpun,
416 "ibm,ppc-interrupt-server#s",
417 cpu, thread))
418 return true;
419
420 return __of_find_n_match_cpu_property(cpun, "reg", cpu, thread);
421}
422
423/**
424 * of_get_cpu_node - Get device node associated with the given logical CPU
425 *
426 * @cpu: CPU number(logical index) for which device node is required
427 * @thread: if not NULL, local thread number within the physical core is
428 * returned
429 *
430 * The main purpose of this function is to retrieve the device node for the
431 * given logical CPU index. It should be used to initialize the of_node in
432 * cpu device. Once of_node in cpu device is populated, all the further
433 * references can use that instead.
434 *
435 * CPU logical to physical index mapping is architecture specific and is built
436 * before booting secondary cores. This function uses arch_match_cpu_phys_id
437 * which can be overridden by architecture specific implementation.
438 *
439 * Returns a node pointer for the logical cpu with refcount incremented, use
440 * of_node_put() on it when done. Returns NULL if not found.
441 */
442struct device_node *of_get_cpu_node(int cpu, unsigned int *thread)
443{
444 struct device_node *cpun;
445
446 for_each_of_cpu_node(cpun) {
447 if (arch_find_n_match_cpu_physical_id(cpun, cpu, thread))
448 return cpun;
449 }
450 return NULL;
451}
452EXPORT_SYMBOL(of_get_cpu_node);
453
454/**
455 * of_cpu_node_to_id: Get the logical CPU number for a given device_node
456 *
457 * @cpu_node: Pointer to the device_node for CPU.
458 *
459 * Returns the logical CPU number of the given CPU device_node.
460 * Returns -ENODEV if the CPU is not found.
461 */
462int of_cpu_node_to_id(struct device_node *cpu_node)
463{
464 int cpu;
465 bool found = false;
466 struct device_node *np;
467
468 for_each_possible_cpu(cpu) {
469 np = of_cpu_device_node_get(cpu);
470 found = (cpu_node == np);
471 of_node_put(np);
472 if (found)
473 return cpu;
474 }
475
476 return -ENODEV;
477}
478EXPORT_SYMBOL(of_cpu_node_to_id);
479
480/**
481 * __of_device_is_compatible() - Check if the node matches given constraints
482 * @device: pointer to node
483 * @compat: required compatible string, NULL or "" for any match
484 * @type: required device_type value, NULL or "" for any match
485 * @name: required node name, NULL or "" for any match
486 *
487 * Checks if the given @compat, @type and @name strings match the
488 * properties of the given @device. A constraints can be skipped by
489 * passing NULL or an empty string as the constraint.
490 *
491 * Returns 0 for no match, and a positive integer on match. The return
492 * value is a relative score with larger values indicating better
493 * matches. The score is weighted for the most specific compatible value
494 * to get the highest score. Matching type is next, followed by matching
495 * name. Practically speaking, this results in the following priority
496 * order for matches:
497 *
498 * 1. specific compatible && type && name
499 * 2. specific compatible && type
500 * 3. specific compatible && name
501 * 4. specific compatible
502 * 5. general compatible && type && name
503 * 6. general compatible && type
504 * 7. general compatible && name
505 * 8. general compatible
506 * 9. type && name
507 * 10. type
508 * 11. name
509 */
510static int __of_device_is_compatible(const struct device_node *device,
511 const char *compat, const char *type, const char *name)
512{
513 struct property *prop;
514 const char *cp;
515 int index = 0, score = 0;
516
517 /* Compatible match has highest priority */
518 if (compat && compat[0]) {
519 prop = __of_find_property(device, "compatible", NULL);
520 for (cp = of_prop_next_string(prop, NULL); cp;
521 cp = of_prop_next_string(prop, cp), index++) {
522 if (of_compat_cmp(cp, compat, strlen(compat)) == 0) {
523 score = INT_MAX/2 - (index << 2);
524 break;
525 }
526 }
527 if (!score)
528 return 0;
529 }
530
531 /* Matching type is better than matching name */
532 if (type && type[0]) {
533 if (!__of_node_is_type(device, type))
534 return 0;
535 score += 2;
536 }
537
538 /* Matching name is a bit better than not */
539 if (name && name[0]) {
540 if (!of_node_name_eq(device, name))
541 return 0;
542 score++;
543 }
544
545 return score;
546}
547
548/** Checks if the given "compat" string matches one of the strings in
549 * the device's "compatible" property
550 */
551int of_device_is_compatible(const struct device_node *device,
552 const char *compat)
553{
554 unsigned long flags;
555 int res;
556
557 raw_spin_lock_irqsave(&devtree_lock, flags);
558 res = __of_device_is_compatible(device, compat, NULL, NULL);
559 raw_spin_unlock_irqrestore(&devtree_lock, flags);
560 return res;
561}
562EXPORT_SYMBOL(of_device_is_compatible);
563
564/** Checks if the device is compatible with any of the entries in
565 * a NULL terminated array of strings. Returns the best match
566 * score or 0.
567 */
568int of_device_compatible_match(struct device_node *device,
569 const char *const *compat)
570{
571 unsigned int tmp, score = 0;
572
573 if (!compat)
574 return 0;
575
576 while (*compat) {
577 tmp = of_device_is_compatible(device, *compat);
578 if (tmp > score)
579 score = tmp;
580 compat++;
581 }
582
583 return score;
584}
585
586/**
587 * of_machine_is_compatible - Test root of device tree for a given compatible value
588 * @compat: compatible string to look for in root node's compatible property.
589 *
590 * Returns a positive integer if the root node has the given value in its
591 * compatible property.
592 */
593int of_machine_is_compatible(const char *compat)
594{
595 struct device_node *root;
596 int rc = 0;
597
598 root = of_find_node_by_path("/");
599 if (root) {
600 rc = of_device_is_compatible(root, compat);
601 of_node_put(root);
602 }
603 return rc;
604}
605EXPORT_SYMBOL(of_machine_is_compatible);
606
607/**
608 * __of_device_is_available - check if a device is available for use
609 *
610 * @device: Node to check for availability, with locks already held
611 *
612 * Returns true if the status property is absent or set to "okay" or "ok",
613 * false otherwise
614 */
615static bool __of_device_is_available(const struct device_node *device)
616{
617 const char *status;
618 int statlen;
619
620 if (!device)
621 return false;
622
623 status = __of_get_property(device, "status", &statlen);
624 if (status == NULL)
625 return true;
626
627 if (statlen > 0) {
628 if (!strcmp(status, "okay") || !strcmp(status, "ok"))
629 return true;
630 }
631
632 return false;
633}
634
635/**
636 * of_device_is_available - check if a device is available for use
637 *
638 * @device: Node to check for availability
639 *
640 * Returns true if the status property is absent or set to "okay" or "ok",
641 * false otherwise
642 */
643bool of_device_is_available(const struct device_node *device)
644{
645 unsigned long flags;
646 bool res;
647
648 raw_spin_lock_irqsave(&devtree_lock, flags);
649 res = __of_device_is_available(device);
650 raw_spin_unlock_irqrestore(&devtree_lock, flags);
651 return res;
652
653}
654EXPORT_SYMBOL(of_device_is_available);
655
656/**
657 * of_device_is_big_endian - check if a device has BE registers
658 *
659 * @device: Node to check for endianness
660 *
661 * Returns true if the device has a "big-endian" property, or if the kernel
662 * was compiled for BE *and* the device has a "native-endian" property.
663 * Returns false otherwise.
664 *
665 * Callers would nominally use ioread32be/iowrite32be if
666 * of_device_is_big_endian() == true, or readl/writel otherwise.
667 */
668bool of_device_is_big_endian(const struct device_node *device)
669{
670 if (of_property_read_bool(device, "big-endian"))
671 return true;
672 if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) &&
673 of_property_read_bool(device, "native-endian"))
674 return true;
675 return false;
676}
677EXPORT_SYMBOL(of_device_is_big_endian);
678
679/**
680 * of_get_parent - Get a node's parent if any
681 * @node: Node to get parent
682 *
683 * Returns a node pointer with refcount incremented, use
684 * of_node_put() on it when done.
685 */
686struct device_node *of_get_parent(const struct device_node *node)
687{
688 struct device_node *np;
689 unsigned long flags;
690
691 if (!node)
692 return NULL;
693
694 raw_spin_lock_irqsave(&devtree_lock, flags);
695 np = of_node_get(node->parent);
696 raw_spin_unlock_irqrestore(&devtree_lock, flags);
697 return np;
698}
699EXPORT_SYMBOL(of_get_parent);
700
701/**
702 * of_get_next_parent - Iterate to a node's parent
703 * @node: Node to get parent of
704 *
705 * This is like of_get_parent() except that it drops the
706 * refcount on the passed node, making it suitable for iterating
707 * through a node's parents.
708 *
709 * Returns a node pointer with refcount incremented, use
710 * of_node_put() on it when done.
711 */
712struct device_node *of_get_next_parent(struct device_node *node)
713{
714 struct device_node *parent;
715 unsigned long flags;
716
717 if (!node)
718 return NULL;
719
720 raw_spin_lock_irqsave(&devtree_lock, flags);
721 parent = of_node_get(node->parent);
722 of_node_put(node);
723 raw_spin_unlock_irqrestore(&devtree_lock, flags);
724 return parent;
725}
726EXPORT_SYMBOL(of_get_next_parent);
727
728static struct device_node *__of_get_next_child(const struct device_node *node,
729 struct device_node *prev)
730{
731 struct device_node *next;
732
733 if (!node)
734 return NULL;
735
736 next = prev ? prev->sibling : node->child;
737 for (; next; next = next->sibling)
738 if (of_node_get(next))
739 break;
740 of_node_put(prev);
741 return next;
742}
743#define __for_each_child_of_node(parent, child) \
744 for (child = __of_get_next_child(parent, NULL); child != NULL; \
745 child = __of_get_next_child(parent, child))
746
747/**
748 * of_get_next_child - Iterate a node childs
749 * @node: parent node
750 * @prev: previous child of the parent node, or NULL to get first
751 *
752 * Returns a node pointer with refcount incremented, use of_node_put() on
753 * it when done. Returns NULL when prev is the last child. Decrements the
754 * refcount of prev.
755 */
756struct device_node *of_get_next_child(const struct device_node *node,
757 struct device_node *prev)
758{
759 struct device_node *next;
760 unsigned long flags;
761
762 raw_spin_lock_irqsave(&devtree_lock, flags);
763 next = __of_get_next_child(node, prev);
764 raw_spin_unlock_irqrestore(&devtree_lock, flags);
765 return next;
766}
767EXPORT_SYMBOL(of_get_next_child);
768
769/**
770 * of_get_next_available_child - Find the next available child node
771 * @node: parent node
772 * @prev: previous child of the parent node, or NULL to get first
773 *
774 * This function is like of_get_next_child(), except that it
775 * automatically skips any disabled nodes (i.e. status = "disabled").
776 */
777struct device_node *of_get_next_available_child(const struct device_node *node,
778 struct device_node *prev)
779{
780 struct device_node *next;
781 unsigned long flags;
782
783 if (!node)
784 return NULL;
785
786 raw_spin_lock_irqsave(&devtree_lock, flags);
787 next = prev ? prev->sibling : node->child;
788 for (; next; next = next->sibling) {
789 if (!__of_device_is_available(next))
790 continue;
791 if (of_node_get(next))
792 break;
793 }
794 of_node_put(prev);
795 raw_spin_unlock_irqrestore(&devtree_lock, flags);
796 return next;
797}
798EXPORT_SYMBOL(of_get_next_available_child);
799
800/**
801 * of_get_next_cpu_node - Iterate on cpu nodes
802 * @prev: previous child of the /cpus node, or NULL to get first
803 *
804 * Returns a cpu node pointer with refcount incremented, use of_node_put()
805 * on it when done. Returns NULL when prev is the last child. Decrements
806 * the refcount of prev.
807 */
808struct device_node *of_get_next_cpu_node(struct device_node *prev)
809{
810 struct device_node *next = NULL;
811 unsigned long flags;
812 struct device_node *node;
813
814 if (!prev)
815 node = of_find_node_by_path("/cpus");
816
817 raw_spin_lock_irqsave(&devtree_lock, flags);
818 if (prev)
819 next = prev->sibling;
820 else if (node) {
821 next = node->child;
822 of_node_put(node);
823 }
824 for (; next; next = next->sibling) {
825 if (!(of_node_name_eq(next, "cpu") ||
826 __of_node_is_type(next, "cpu")))
827 continue;
828 if (of_node_get(next))
829 break;
830 }
831 of_node_put(prev);
832 raw_spin_unlock_irqrestore(&devtree_lock, flags);
833 return next;
834}
835EXPORT_SYMBOL(of_get_next_cpu_node);
836
837/**
838 * of_get_compatible_child - Find compatible child node
839 * @parent: parent node
840 * @compatible: compatible string
841 *
842 * Lookup child node whose compatible property contains the given compatible
843 * string.
844 *
845 * Returns a node pointer with refcount incremented, use of_node_put() on it
846 * when done; or NULL if not found.
847 */
848struct device_node *of_get_compatible_child(const struct device_node *parent,
849 const char *compatible)
850{
851 struct device_node *child;
852
853 for_each_child_of_node(parent, child) {
854 if (of_device_is_compatible(child, compatible))
855 break;
856 }
857
858 return child;
859}
860EXPORT_SYMBOL(of_get_compatible_child);
861
862/**
863 * of_get_child_by_name - Find the child node by name for a given parent
864 * @node: parent node
865 * @name: child name to look for.
866 *
867 * This function looks for child node for given matching name
868 *
869 * Returns a node pointer if found, with refcount incremented, use
870 * of_node_put() on it when done.
871 * Returns NULL if node is not found.
872 */
873struct device_node *of_get_child_by_name(const struct device_node *node,
874 const char *name)
875{
876 struct device_node *child;
877
878 for_each_child_of_node(node, child)
879 if (of_node_name_eq(child, name))
880 break;
881 return child;
882}
883EXPORT_SYMBOL(of_get_child_by_name);
884
885struct device_node *__of_find_node_by_path(struct device_node *parent,
886 const char *path)
887{
888 struct device_node *child;
889 int len;
890
891 len = strcspn(path, "/:");
892 if (!len)
893 return NULL;
894
895 __for_each_child_of_node(parent, child) {
896 const char *name = kbasename(child->full_name);
897 if (strncmp(path, name, len) == 0 && (strlen(name) == len))
898 return child;
899 }
900 return NULL;
901}
902
903struct device_node *__of_find_node_by_full_path(struct device_node *node,
904 const char *path)
905{
906 const char *separator = strchr(path, ':');
907
908 while (node && *path == '/') {
909 struct device_node *tmp = node;
910
911 path++; /* Increment past '/' delimiter */
912 node = __of_find_node_by_path(node, path);
913 of_node_put(tmp);
914 path = strchrnul(path, '/');
915 if (separator && separator < path)
916 break;
917 }
918 return node;
919}
920
921/**
922 * of_find_node_opts_by_path - Find a node matching a full OF path
923 * @path: Either the full path to match, or if the path does not
924 * start with '/', the name of a property of the /aliases
925 * node (an alias). In the case of an alias, the node
926 * matching the alias' value will be returned.
927 * @opts: Address of a pointer into which to store the start of
928 * an options string appended to the end of the path with
929 * a ':' separator.
930 *
931 * Valid paths:
932 * /foo/bar Full path
933 * foo Valid alias
934 * foo/bar Valid alias + relative path
935 *
936 * Returns a node pointer with refcount incremented, use
937 * of_node_put() on it when done.
938 */
939struct device_node *of_find_node_opts_by_path(const char *path, const char **opts)
940{
941 struct device_node *np = NULL;
942 struct property *pp;
943 unsigned long flags;
944 const char *separator = strchr(path, ':');
945
946 if (opts)
947 *opts = separator ? separator + 1 : NULL;
948
949 if (strcmp(path, "/") == 0)
950 return of_node_get(of_root);
951
952 /* The path could begin with an alias */
953 if (*path != '/') {
954 int len;
955 const char *p = separator;
956
957 if (!p)
958 p = strchrnul(path, '/');
959 len = p - path;
960
961 /* of_aliases must not be NULL */
962 if (!of_aliases)
963 return NULL;
964
965 for_each_property_of_node(of_aliases, pp) {
966 if (strlen(pp->name) == len && !strncmp(pp->name, path, len)) {
967 np = of_find_node_by_path(pp->value);
968 break;
969 }
970 }
971 if (!np)
972 return NULL;
973 path = p;
974 }
975
976 /* Step down the tree matching path components */
977 raw_spin_lock_irqsave(&devtree_lock, flags);
978 if (!np)
979 np = of_node_get(of_root);
980 np = __of_find_node_by_full_path(np, path);
981 raw_spin_unlock_irqrestore(&devtree_lock, flags);
982 return np;
983}
984EXPORT_SYMBOL(of_find_node_opts_by_path);
985
986/**
987 * of_find_node_by_name - Find a node by its "name" property
988 * @from: The node to start searching from or NULL; the node
989 * you pass will not be searched, only the next one
990 * will. Typically, you pass what the previous call
991 * returned. of_node_put() will be called on @from.
992 * @name: The name string to match against
993 *
994 * Returns a node pointer with refcount incremented, use
995 * of_node_put() on it when done.
996 */
997struct device_node *of_find_node_by_name(struct device_node *from,
998 const char *name)
999{
1000 struct device_node *np;
1001 unsigned long flags;
1002
1003 raw_spin_lock_irqsave(&devtree_lock, flags);
1004 for_each_of_allnodes_from(from, np)
1005 if (of_node_name_eq(np, name) && of_node_get(np))
1006 break;
1007 of_node_put(from);
1008 raw_spin_unlock_irqrestore(&devtree_lock, flags);
1009 return np;
1010}
1011EXPORT_SYMBOL(of_find_node_by_name);
1012
1013/**
1014 * of_find_node_by_type - Find a node by its "device_type" property
1015 * @from: The node to start searching from, or NULL to start searching
1016 * the entire device tree. The node you pass will not be
1017 * searched, only the next one will; typically, you pass
1018 * what the previous call returned. of_node_put() will be
1019 * called on from for you.
1020 * @type: The type string to match against
1021 *
1022 * Returns a node pointer with refcount incremented, use
1023 * of_node_put() on it when done.
1024 */
1025struct device_node *of_find_node_by_type(struct device_node *from,
1026 const char *type)
1027{
1028 struct device_node *np;
1029 unsigned long flags;
1030
1031 raw_spin_lock_irqsave(&devtree_lock, flags);
1032 for_each_of_allnodes_from(from, np)
1033 if (__of_node_is_type(np, type) && of_node_get(np))
1034 break;
1035 of_node_put(from);
1036 raw_spin_unlock_irqrestore(&devtree_lock, flags);
1037 return np;
1038}
1039EXPORT_SYMBOL(of_find_node_by_type);
1040
1041/**
1042 * of_find_compatible_node - Find a node based on type and one of the
1043 * tokens in its "compatible" property
1044 * @from: The node to start searching from or NULL, the node
1045 * you pass will not be searched, only the next one
1046 * will; typically, you pass what the previous call
1047 * returned. of_node_put() will be called on it
1048 * @type: The type string to match "device_type" or NULL to ignore
1049 * @compatible: The string to match to one of the tokens in the device
1050 * "compatible" list.
1051 *
1052 * Returns a node pointer with refcount incremented, use
1053 * of_node_put() on it when done.
1054 */
1055struct device_node *of_find_compatible_node(struct device_node *from,
1056 const char *type, const char *compatible)
1057{
1058 struct device_node *np;
1059 unsigned long flags;
1060
1061 raw_spin_lock_irqsave(&devtree_lock, flags);
1062 for_each_of_allnodes_from(from, np)
1063 if (__of_device_is_compatible(np, compatible, type, NULL) &&
1064 of_node_get(np))
1065 break;
1066 of_node_put(from);
1067 raw_spin_unlock_irqrestore(&devtree_lock, flags);
1068 return np;
1069}
1070EXPORT_SYMBOL(of_find_compatible_node);
1071
1072/**
1073 * of_find_node_with_property - Find a node which has a property with
1074 * the given name.
1075 * @from: The node to start searching from or NULL, the node
1076 * you pass will not be searched, only the next one
1077 * will; typically, you pass what the previous call
1078 * returned. of_node_put() will be called on it
1079 * @prop_name: The name of the property to look for.
1080 *
1081 * Returns a node pointer with refcount incremented, use
1082 * of_node_put() on it when done.
1083 */
1084struct device_node *of_find_node_with_property(struct device_node *from,
1085 const char *prop_name)
1086{
1087 struct device_node *np;
1088 struct property *pp;
1089 unsigned long flags;
1090
1091 raw_spin_lock_irqsave(&devtree_lock, flags);
1092 for_each_of_allnodes_from(from, np) {
1093 for (pp = np->properties; pp; pp = pp->next) {
1094 if (of_prop_cmp(pp->name, prop_name) == 0) {
1095 of_node_get(np);
1096 goto out;
1097 }
1098 }
1099 }
1100out:
1101 of_node_put(from);
1102 raw_spin_unlock_irqrestore(&devtree_lock, flags);
1103 return np;
1104}
1105EXPORT_SYMBOL(of_find_node_with_property);
1106
1107static
1108const struct of_device_id *__of_match_node(const struct of_device_id *matches,
1109 const struct device_node *node)
1110{
1111 const struct of_device_id *best_match = NULL;
1112 int score, best_score = 0;
1113
1114 if (!matches)
1115 return NULL;
1116
1117 for (; matches->name[0] || matches->type[0] || matches->compatible[0]; matches++) {
1118 score = __of_device_is_compatible(node, matches->compatible,
1119 matches->type, matches->name);
1120 if (score > best_score) {
1121 best_match = matches;
1122 best_score = score;
1123 }
1124 }
1125
1126 return best_match;
1127}
1128
1129/**
1130 * of_match_node - Tell if a device_node has a matching of_match structure
1131 * @matches: array of of device match structures to search in
1132 * @node: the of device structure to match against
1133 *
1134 * Low level utility function used by device matching.
1135 */
1136const struct of_device_id *of_match_node(const struct of_device_id *matches,
1137 const struct device_node *node)
1138{
1139 const struct of_device_id *match;
1140 unsigned long flags;
1141
1142 raw_spin_lock_irqsave(&devtree_lock, flags);
1143 match = __of_match_node(matches, node);
1144 raw_spin_unlock_irqrestore(&devtree_lock, flags);
1145 return match;
1146}
1147EXPORT_SYMBOL(of_match_node);
1148
1149/**
1150 * of_find_matching_node_and_match - Find a node based on an of_device_id
1151 * match table.
1152 * @from: The node to start searching from or NULL, the node
1153 * you pass will not be searched, only the next one
1154 * will; typically, you pass what the previous call
1155 * returned. of_node_put() will be called on it
1156 * @matches: array of of device match structures to search in
1157 * @match Updated to point at the matches entry which matched
1158 *
1159 * Returns a node pointer with refcount incremented, use
1160 * of_node_put() on it when done.
1161 */
1162struct device_node *of_find_matching_node_and_match(struct device_node *from,
1163 const struct of_device_id *matches,
1164 const struct of_device_id **match)
1165{
1166 struct device_node *np;
1167 const struct of_device_id *m;
1168 unsigned long flags;
1169
1170 if (match)
1171 *match = NULL;
1172
1173 raw_spin_lock_irqsave(&devtree_lock, flags);
1174 for_each_of_allnodes_from(from, np) {
1175 m = __of_match_node(matches, np);
1176 if (m && of_node_get(np)) {
1177 if (match)
1178 *match = m;
1179 break;
1180 }
1181 }
1182 of_node_put(from);
1183 raw_spin_unlock_irqrestore(&devtree_lock, flags);
1184 return np;
1185}
1186EXPORT_SYMBOL(of_find_matching_node_and_match);
1187
1188/**
1189 * of_modalias_node - Lookup appropriate modalias for a device node
1190 * @node: pointer to a device tree node
1191 * @modalias: Pointer to buffer that modalias value will be copied into
1192 * @len: Length of modalias value
1193 *
1194 * Based on the value of the compatible property, this routine will attempt
1195 * to choose an appropriate modalias value for a particular device tree node.
1196 * It does this by stripping the manufacturer prefix (as delimited by a ',')
1197 * from the first entry in the compatible list property.
1198 *
1199 * This routine returns 0 on success, <0 on failure.
1200 */
1201int of_modalias_node(struct device_node *node, char *modalias, int len)
1202{
1203 const char *compatible, *p;
1204 int cplen;
1205
1206 compatible = of_get_property(node, "compatible", &cplen);
1207 if (!compatible || strlen(compatible) > cplen)
1208 return -ENODEV;
1209 p = strchr(compatible, ',');
1210 strlcpy(modalias, p ? p + 1 : compatible, len);
1211 return 0;
1212}
1213EXPORT_SYMBOL_GPL(of_modalias_node);
1214
1215/**
1216 * of_find_node_by_phandle - Find a node given a phandle
1217 * @handle: phandle of the node to find
1218 *
1219 * Returns a node pointer with refcount incremented, use
1220 * of_node_put() on it when done.
1221 */
1222struct device_node *of_find_node_by_phandle(phandle handle)
1223{
1224 struct device_node *np = NULL;
1225 unsigned long flags;
1226 phandle masked_handle;
1227
1228 if (!handle)
1229 return NULL;
1230
1231 raw_spin_lock_irqsave(&devtree_lock, flags);
1232
1233 masked_handle = handle & phandle_cache_mask;
1234
1235 if (phandle_cache) {
1236 if (phandle_cache[masked_handle] &&
1237 handle == phandle_cache[masked_handle]->phandle)
1238 np = phandle_cache[masked_handle];
1239 if (np && of_node_check_flag(np, OF_DETACHED)) {
1240 WARN_ON(1); /* did not uncache np on node removal */
1241 of_node_put(np);
1242 phandle_cache[masked_handle] = NULL;
1243 np = NULL;
1244 }
1245 }
1246
1247 if (!np) {
1248 for_each_of_allnodes(np)
1249 if (np->phandle == handle &&
1250 !of_node_check_flag(np, OF_DETACHED)) {
1251 if (phandle_cache) {
1252 /* will put when removed from cache */
1253 of_node_get(np);
1254 phandle_cache[masked_handle] = np;
1255 }
1256 break;
1257 }
1258 }
1259
1260 of_node_get(np);
1261 raw_spin_unlock_irqrestore(&devtree_lock, flags);
1262 return np;
1263}
1264EXPORT_SYMBOL(of_find_node_by_phandle);
1265
1266void of_print_phandle_args(const char *msg, const struct of_phandle_args *args)
1267{
1268 int i;
1269 printk("%s %pOF", msg, args->np);
1270 for (i = 0; i < args->args_count; i++) {
1271 const char delim = i ? ',' : ':';
1272
1273 pr_cont("%c%08x", delim, args->args[i]);
1274 }
1275 pr_cont("\n");
1276}
1277
1278int of_phandle_iterator_init(struct of_phandle_iterator *it,
1279 const struct device_node *np,
1280 const char *list_name,
1281 const char *cells_name,
1282 int cell_count)
1283{
1284 const __be32 *list;
1285 int size;
1286
1287 memset(it, 0, sizeof(*it));
1288
1289 list = of_get_property(np, list_name, &size);
1290 if (!list)
1291 return -ENOENT;
1292
1293 it->cells_name = cells_name;
1294 it->cell_count = cell_count;
1295 it->parent = np;
1296 it->list_end = list + size / sizeof(*list);
1297 it->phandle_end = list;
1298 it->cur = list;
1299
1300 return 0;
1301}
1302EXPORT_SYMBOL_GPL(of_phandle_iterator_init);
1303
1304int of_phandle_iterator_next(struct of_phandle_iterator *it)
1305{
1306 uint32_t count = 0;
1307
1308 if (it->node) {
1309 of_node_put(it->node);
1310 it->node = NULL;
1311 }
1312
1313 if (!it->cur || it->phandle_end >= it->list_end)
1314 return -ENOENT;
1315
1316 it->cur = it->phandle_end;
1317
1318 /* If phandle is 0, then it is an empty entry with no arguments. */
1319 it->phandle = be32_to_cpup(it->cur++);
1320
1321 if (it->phandle) {
1322
1323 /*
1324 * Find the provider node and parse the #*-cells property to
1325 * determine the argument length.
1326 */
1327 it->node = of_find_node_by_phandle(it->phandle);
1328
1329 if (it->cells_name) {
1330 if (!it->node) {
1331 pr_err("%pOF: could not find phandle\n",
1332 it->parent);
1333 goto err;
1334 }
1335
1336 if (of_property_read_u32(it->node, it->cells_name,
1337 &count)) {
1338 pr_err("%pOF: could not get %s for %pOF\n",
1339 it->parent,
1340 it->cells_name,
1341 it->node);
1342 goto err;
1343 }
1344 } else {
1345 count = it->cell_count;
1346 }
1347
1348 /*
1349 * Make sure that the arguments actually fit in the remaining
1350 * property data length
1351 */
1352 if (it->cur + count > it->list_end) {
1353 pr_err("%pOF: arguments longer than property\n",
1354 it->parent);
1355 goto err;
1356 }
1357 }
1358
1359 it->phandle_end = it->cur + count;
1360 it->cur_count = count;
1361
1362 return 0;
1363
1364err:
1365 if (it->node) {
1366 of_node_put(it->node);
1367 it->node = NULL;
1368 }
1369
1370 return -EINVAL;
1371}
1372EXPORT_SYMBOL_GPL(of_phandle_iterator_next);
1373
1374int of_phandle_iterator_args(struct of_phandle_iterator *it,
1375 uint32_t *args,
1376 int size)
1377{
1378 int i, count;
1379
1380 count = it->cur_count;
1381
1382 if (WARN_ON(size < count))
1383 count = size;
1384
1385 for (i = 0; i < count; i++)
1386 args[i] = be32_to_cpup(it->cur++);
1387
1388 return count;
1389}
1390
1391static int __of_parse_phandle_with_args(const struct device_node *np,
1392 const char *list_name,
1393 const char *cells_name,
1394 int cell_count, int index,
1395 struct of_phandle_args *out_args)
1396{
1397 struct of_phandle_iterator it;
1398 int rc, cur_index = 0;
1399
1400 /* Loop over the phandles until all the requested entry is found */
1401 of_for_each_phandle(&it, rc, np, list_name, cells_name, cell_count) {
1402 /*
1403 * All of the error cases bail out of the loop, so at
1404 * this point, the parsing is successful. If the requested
1405 * index matches, then fill the out_args structure and return,
1406 * or return -ENOENT for an empty entry.
1407 */
1408 rc = -ENOENT;
1409 if (cur_index == index) {
1410 if (!it.phandle)
1411 goto err;
1412
1413 if (out_args) {
1414 int c;
1415
1416 c = of_phandle_iterator_args(&it,
1417 out_args->args,
1418 MAX_PHANDLE_ARGS);
1419 out_args->np = it.node;
1420 out_args->args_count = c;
1421 } else {
1422 of_node_put(it.node);
1423 }
1424
1425 /* Found it! return success */
1426 return 0;
1427 }
1428
1429 cur_index++;
1430 }
1431
1432 /*
1433 * Unlock node before returning result; will be one of:
1434 * -ENOENT : index is for empty phandle
1435 * -EINVAL : parsing error on data
1436 */
1437
1438 err:
1439 of_node_put(it.node);
1440 return rc;
1441}
1442
1443/**
1444 * of_parse_phandle - Resolve a phandle property to a device_node pointer
1445 * @np: Pointer to device node holding phandle property
1446 * @phandle_name: Name of property holding a phandle value
1447 * @index: For properties holding a table of phandles, this is the index into
1448 * the table
1449 *
1450 * Returns the device_node pointer with refcount incremented. Use
1451 * of_node_put() on it when done.
1452 */
1453struct device_node *of_parse_phandle(const struct device_node *np,
1454 const char *phandle_name, int index)
1455{
1456 struct of_phandle_args args;
1457
1458 if (index < 0)
1459 return NULL;
1460
1461 if (__of_parse_phandle_with_args(np, phandle_name, NULL, 0,
1462 index, &args))
1463 return NULL;
1464
1465 return args.np;
1466}
1467EXPORT_SYMBOL(of_parse_phandle);
1468
1469/**
1470 * of_parse_phandle_with_args() - Find a node pointed by phandle in a list
1471 * @np: pointer to a device tree node containing a list
1472 * @list_name: property name that contains a list
1473 * @cells_name: property name that specifies phandles' arguments count
1474 * @index: index of a phandle to parse out
1475 * @out_args: optional pointer to output arguments structure (will be filled)
1476 *
1477 * This function is useful to parse lists of phandles and their arguments.
1478 * Returns 0 on success and fills out_args, on error returns appropriate
1479 * errno value.
1480 *
1481 * Caller is responsible to call of_node_put() on the returned out_args->np
1482 * pointer.
1483 *
1484 * Example:
1485 *
1486 * phandle1: node1 {
1487 * #list-cells = <2>;
1488 * }
1489 *
1490 * phandle2: node2 {
1491 * #list-cells = <1>;
1492 * }
1493 *
1494 * node3 {
1495 * list = <&phandle1 1 2 &phandle2 3>;
1496 * }
1497 *
1498 * To get a device_node of the `node2' node you may call this:
1499 * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
1500 */
1501int of_parse_phandle_with_args(const struct device_node *np, const char *list_name,
1502 const char *cells_name, int index,
1503 struct of_phandle_args *out_args)
1504{
1505 if (index < 0)
1506 return -EINVAL;
1507 return __of_parse_phandle_with_args(np, list_name, cells_name, 0,
1508 index, out_args);
1509}
1510EXPORT_SYMBOL(of_parse_phandle_with_args);
1511
1512/**
1513 * of_parse_phandle_with_args_map() - Find a node pointed by phandle in a list and remap it
1514 * @np: pointer to a device tree node containing a list
1515 * @list_name: property name that contains a list
1516 * @stem_name: stem of property names that specify phandles' arguments count
1517 * @index: index of a phandle to parse out
1518 * @out_args: optional pointer to output arguments structure (will be filled)
1519 *
1520 * This function is useful to parse lists of phandles and their arguments.
1521 * Returns 0 on success and fills out_args, on error returns appropriate errno
1522 * value. The difference between this function and of_parse_phandle_with_args()
1523 * is that this API remaps a phandle if the node the phandle points to has
1524 * a <@stem_name>-map property.
1525 *
1526 * Caller is responsible to call of_node_put() on the returned out_args->np
1527 * pointer.
1528 *
1529 * Example:
1530 *
1531 * phandle1: node1 {
1532 * #list-cells = <2>;
1533 * }
1534 *
1535 * phandle2: node2 {
1536 * #list-cells = <1>;
1537 * }
1538 *
1539 * phandle3: node3 {
1540 * #list-cells = <1>;
1541 * list-map = <0 &phandle2 3>,
1542 * <1 &phandle2 2>,
1543 * <2 &phandle1 5 1>;
1544 * list-map-mask = <0x3>;
1545 * };
1546 *
1547 * node4 {
1548 * list = <&phandle1 1 2 &phandle3 0>;
1549 * }
1550 *
1551 * To get a device_node of the `node2' node you may call this:
1552 * of_parse_phandle_with_args(node4, "list", "list", 1, &args);
1553 */
1554int of_parse_phandle_with_args_map(const struct device_node *np,
1555 const char *list_name,
1556 const char *stem_name,
1557 int index, struct of_phandle_args *out_args)
1558{
1559 char *cells_name, *map_name = NULL, *mask_name = NULL;
1560 char *pass_name = NULL;
1561 struct device_node *cur, *new = NULL;
1562 const __be32 *map, *mask, *pass;
1563 static const __be32 dummy_mask[] = { [0 ... MAX_PHANDLE_ARGS] = ~0 };
1564 static const __be32 dummy_pass[] = { [0 ... MAX_PHANDLE_ARGS] = 0 };
1565 __be32 initial_match_array[MAX_PHANDLE_ARGS];
1566 const __be32 *match_array = initial_match_array;
1567 int i, ret, map_len, match;
1568 u32 list_size, new_size;
1569
1570 if (index < 0)
1571 return -EINVAL;
1572
1573 cells_name = kasprintf(GFP_KERNEL, "#%s-cells", stem_name);
1574 if (!cells_name)
1575 return -ENOMEM;
1576
1577 ret = -ENOMEM;
1578 map_name = kasprintf(GFP_KERNEL, "%s-map", stem_name);
1579 if (!map_name)
1580 goto free;
1581
1582 mask_name = kasprintf(GFP_KERNEL, "%s-map-mask", stem_name);
1583 if (!mask_name)
1584 goto free;
1585
1586 pass_name = kasprintf(GFP_KERNEL, "%s-map-pass-thru", stem_name);
1587 if (!pass_name)
1588 goto free;
1589
1590 ret = __of_parse_phandle_with_args(np, list_name, cells_name, 0, index,
1591 out_args);
1592 if (ret)
1593 goto free;
1594
1595 /* Get the #<list>-cells property */
1596 cur = out_args->np;
1597 ret = of_property_read_u32(cur, cells_name, &list_size);
1598 if (ret < 0)
1599 goto put;
1600
1601 /* Precalculate the match array - this simplifies match loop */
1602 for (i = 0; i < list_size; i++)
1603 initial_match_array[i] = cpu_to_be32(out_args->args[i]);
1604
1605 ret = -EINVAL;
1606 while (cur) {
1607 /* Get the <list>-map property */
1608 map = of_get_property(cur, map_name, &map_len);
1609 if (!map) {
1610 ret = 0;
1611 goto free;
1612 }
1613 map_len /= sizeof(u32);
1614
1615 /* Get the <list>-map-mask property (optional) */
1616 mask = of_get_property(cur, mask_name, NULL);
1617 if (!mask)
1618 mask = dummy_mask;
1619 /* Iterate through <list>-map property */
1620 match = 0;
1621 while (map_len > (list_size + 1) && !match) {
1622 /* Compare specifiers */
1623 match = 1;
1624 for (i = 0; i < list_size; i++, map_len--)
1625 match &= !((match_array[i] ^ *map++) & mask[i]);
1626
1627 of_node_put(new);
1628 new = of_find_node_by_phandle(be32_to_cpup(map));
1629 map++;
1630 map_len--;
1631
1632 /* Check if not found */
1633 if (!new)
1634 goto put;
1635
1636 if (!of_device_is_available(new))
1637 match = 0;
1638
1639 ret = of_property_read_u32(new, cells_name, &new_size);
1640 if (ret)
1641 goto put;
1642
1643 /* Check for malformed properties */
1644 if (WARN_ON(new_size > MAX_PHANDLE_ARGS))
1645 goto put;
1646 if (map_len < new_size)
1647 goto put;
1648
1649 /* Move forward by new node's #<list>-cells amount */
1650 map += new_size;
1651 map_len -= new_size;
1652 }
1653 if (!match)
1654 goto put;
1655
1656 /* Get the <list>-map-pass-thru property (optional) */
1657 pass = of_get_property(cur, pass_name, NULL);
1658 if (!pass)
1659 pass = dummy_pass;
1660
1661 /*
1662 * Successfully parsed a <list>-map translation; copy new
1663 * specifier into the out_args structure, keeping the
1664 * bits specified in <list>-map-pass-thru.
1665 */
1666 match_array = map - new_size;
1667 for (i = 0; i < new_size; i++) {
1668 __be32 val = *(map - new_size + i);
1669
1670 if (i < list_size) {
1671 val &= ~pass[i];
1672 val |= cpu_to_be32(out_args->args[i]) & pass[i];
1673 }
1674
1675 out_args->args[i] = be32_to_cpu(val);
1676 }
1677 out_args->args_count = list_size = new_size;
1678 /* Iterate again with new provider */
1679 out_args->np = new;
1680 of_node_put(cur);
1681 cur = new;
1682 }
1683put:
1684 of_node_put(cur);
1685 of_node_put(new);
1686free:
1687 kfree(mask_name);
1688 kfree(map_name);
1689 kfree(cells_name);
1690 kfree(pass_name);
1691
1692 return ret;
1693}
1694EXPORT_SYMBOL(of_parse_phandle_with_args_map);
1695
1696/**
1697 * of_parse_phandle_with_fixed_args() - Find a node pointed by phandle in a list
1698 * @np: pointer to a device tree node containing a list
1699 * @list_name: property name that contains a list
1700 * @cell_count: number of argument cells following the phandle
1701 * @index: index of a phandle to parse out
1702 * @out_args: optional pointer to output arguments structure (will be filled)
1703 *
1704 * This function is useful to parse lists of phandles and their arguments.
1705 * Returns 0 on success and fills out_args, on error returns appropriate
1706 * errno value.
1707 *
1708 * Caller is responsible to call of_node_put() on the returned out_args->np
1709 * pointer.
1710 *
1711 * Example:
1712 *
1713 * phandle1: node1 {
1714 * }
1715 *
1716 * phandle2: node2 {
1717 * }
1718 *
1719 * node3 {
1720 * list = <&phandle1 0 2 &phandle2 2 3>;
1721 * }
1722 *
1723 * To get a device_node of the `node2' node you may call this:
1724 * of_parse_phandle_with_fixed_args(node3, "list", 2, 1, &args);
1725 */
1726int of_parse_phandle_with_fixed_args(const struct device_node *np,
1727 const char *list_name, int cell_count,
1728 int index, struct of_phandle_args *out_args)
1729{
1730 if (index < 0)
1731 return -EINVAL;
1732 return __of_parse_phandle_with_args(np, list_name, NULL, cell_count,
1733 index, out_args);
1734}
1735EXPORT_SYMBOL(of_parse_phandle_with_fixed_args);
1736
1737/**
1738 * of_count_phandle_with_args() - Find the number of phandles references in a property
1739 * @np: pointer to a device tree node containing a list
1740 * @list_name: property name that contains a list
1741 * @cells_name: property name that specifies phandles' arguments count
1742 *
1743 * Returns the number of phandle + argument tuples within a property. It
1744 * is a typical pattern to encode a list of phandle and variable
1745 * arguments into a single property. The number of arguments is encoded
1746 * by a property in the phandle-target node. For example, a gpios
1747 * property would contain a list of GPIO specifies consisting of a
1748 * phandle and 1 or more arguments. The number of arguments are
1749 * determined by the #gpio-cells property in the node pointed to by the
1750 * phandle.
1751 */
1752int of_count_phandle_with_args(const struct device_node *np, const char *list_name,
1753 const char *cells_name)
1754{
1755 struct of_phandle_iterator it;
1756 int rc, cur_index = 0;
1757
1758 rc = of_phandle_iterator_init(&it, np, list_name, cells_name, 0);
1759 if (rc)
1760 return rc;
1761
1762 while ((rc = of_phandle_iterator_next(&it)) == 0)
1763 cur_index += 1;
1764
1765 if (rc != -ENOENT)
1766 return rc;
1767
1768 return cur_index;
1769}
1770EXPORT_SYMBOL(of_count_phandle_with_args);
1771
1772/**
1773 * __of_add_property - Add a property to a node without lock operations
1774 */
1775int __of_add_property(struct device_node *np, struct property *prop)
1776{
1777 struct property **next;
1778
1779 prop->next = NULL;
1780 next = &np->properties;
1781 while (*next) {
1782 if (strcmp(prop->name, (*next)->name) == 0)
1783 /* duplicate ! don't insert it */
1784 return -EEXIST;
1785
1786 next = &(*next)->next;
1787 }
1788 *next = prop;
1789
1790 return 0;
1791}
1792
1793/**
1794 * of_add_property - Add a property to a node
1795 */
1796int of_add_property(struct device_node *np, struct property *prop)
1797{
1798 unsigned long flags;
1799 int rc;
1800
1801 mutex_lock(&of_mutex);
1802
1803 raw_spin_lock_irqsave(&devtree_lock, flags);
1804 rc = __of_add_property(np, prop);
1805 raw_spin_unlock_irqrestore(&devtree_lock, flags);
1806
1807 if (!rc)
1808 __of_add_property_sysfs(np, prop);
1809
1810 mutex_unlock(&of_mutex);
1811
1812 if (!rc)
1813 of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop, NULL);
1814
1815 return rc;
1816}
1817
1818int __of_remove_property(struct device_node *np, struct property *prop)
1819{
1820 struct property **next;
1821
1822 for (next = &np->properties; *next; next = &(*next)->next) {
1823 if (*next == prop)
1824 break;
1825 }
1826 if (*next == NULL)
1827 return -ENODEV;
1828
1829 /* found the node */
1830 *next = prop->next;
1831 prop->next = np->deadprops;
1832 np->deadprops = prop;
1833
1834 return 0;
1835}
1836
1837/**
1838 * of_remove_property - Remove a property from a node.
1839 *
1840 * Note that we don't actually remove it, since we have given out
1841 * who-knows-how-many pointers to the data using get-property.
1842 * Instead we just move the property to the "dead properties"
1843 * list, so it won't be found any more.
1844 */
1845int of_remove_property(struct device_node *np, struct property *prop)
1846{
1847 unsigned long flags;
1848 int rc;
1849
1850 if (!prop)
1851 return -ENODEV;
1852
1853 mutex_lock(&of_mutex);
1854
1855 raw_spin_lock_irqsave(&devtree_lock, flags);
1856 rc = __of_remove_property(np, prop);
1857 raw_spin_unlock_irqrestore(&devtree_lock, flags);
1858
1859 if (!rc)
1860 __of_remove_property_sysfs(np, prop);
1861
1862 mutex_unlock(&of_mutex);
1863
1864 if (!rc)
1865 of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop, NULL);
1866
1867 return rc;
1868}
1869
1870int __of_update_property(struct device_node *np, struct property *newprop,
1871 struct property **oldpropp)
1872{
1873 struct property **next, *oldprop;
1874
1875 for (next = &np->properties; *next; next = &(*next)->next) {
1876 if (of_prop_cmp((*next)->name, newprop->name) == 0)
1877 break;
1878 }
1879 *oldpropp = oldprop = *next;
1880
1881 if (oldprop) {
1882 /* replace the node */
1883 newprop->next = oldprop->next;
1884 *next = newprop;
1885 oldprop->next = np->deadprops;
1886 np->deadprops = oldprop;
1887 } else {
1888 /* new node */
1889 newprop->next = NULL;
1890 *next = newprop;
1891 }
1892
1893 return 0;
1894}
1895
1896/*
1897 * of_update_property - Update a property in a node, if the property does
1898 * not exist, add it.
1899 *
1900 * Note that we don't actually remove it, since we have given out
1901 * who-knows-how-many pointers to the data using get-property.
1902 * Instead we just move the property to the "dead properties" list,
1903 * and add the new property to the property list
1904 */
1905int of_update_property(struct device_node *np, struct property *newprop)
1906{
1907 struct property *oldprop;
1908 unsigned long flags;
1909 int rc;
1910
1911 if (!newprop->name)
1912 return -EINVAL;
1913
1914 mutex_lock(&of_mutex);
1915
1916 raw_spin_lock_irqsave(&devtree_lock, flags);
1917 rc = __of_update_property(np, newprop, &oldprop);
1918 raw_spin_unlock_irqrestore(&devtree_lock, flags);
1919
1920 if (!rc)
1921 __of_update_property_sysfs(np, newprop, oldprop);
1922
1923 mutex_unlock(&of_mutex);
1924
1925 if (!rc)
1926 of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop, oldprop);
1927
1928 return rc;
1929}
1930
1931static void of_alias_add(struct alias_prop *ap, struct device_node *np,
1932 int id, const char *stem, int stem_len)
1933{
1934 ap->np = np;
1935 ap->id = id;
1936 strncpy(ap->stem, stem, stem_len);
1937 ap->stem[stem_len] = 0;
1938 list_add_tail(&ap->link, &aliases_lookup);
1939 pr_debug("adding DT alias:%s: stem=%s id=%i node=%pOF\n",
1940 ap->alias, ap->stem, ap->id, np);
1941}
1942
1943/**
1944 * of_alias_scan - Scan all properties of the 'aliases' node
1945 *
1946 * The function scans all the properties of the 'aliases' node and populates
1947 * the global lookup table with the properties. It returns the
1948 * number of alias properties found, or an error code in case of failure.
1949 *
1950 * @dt_alloc: An allocator that provides a virtual address to memory
1951 * for storing the resulting tree
1952 */
1953void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align))
1954{
1955 struct property *pp;
1956
1957 of_aliases = of_find_node_by_path("/aliases");
1958 of_chosen = of_find_node_by_path("/chosen");
1959 if (of_chosen == NULL)
1960 of_chosen = of_find_node_by_path("/chosen@0");
1961
1962 if (of_chosen) {
1963 /* linux,stdout-path and /aliases/stdout are for legacy compatibility */
1964 const char *name = NULL;
1965
1966 if (of_property_read_string(of_chosen, "stdout-path", &name))
1967 of_property_read_string(of_chosen, "linux,stdout-path",
1968 &name);
1969 if (IS_ENABLED(CONFIG_PPC) && !name)
1970 of_property_read_string(of_aliases, "stdout", &name);
1971 if (name)
1972 of_stdout = of_find_node_opts_by_path(name, &of_stdout_options);
1973 }
1974
1975 if (!of_aliases)
1976 return;
1977
1978 for_each_property_of_node(of_aliases, pp) {
1979 const char *start = pp->name;
1980 const char *end = start + strlen(start);
1981 struct device_node *np;
1982 struct alias_prop *ap;
1983 int id, len;
1984
1985 /* Skip those we do not want to proceed */
1986 if (!strcmp(pp->name, "name") ||
1987 !strcmp(pp->name, "phandle") ||
1988 !strcmp(pp->name, "linux,phandle"))
1989 continue;
1990
1991 np = of_find_node_by_path(pp->value);
1992 if (!np)
1993 continue;
1994
1995 /* walk the alias backwards to extract the id and work out
1996 * the 'stem' string */
1997 while (isdigit(*(end-1)) && end > start)
1998 end--;
1999 len = end - start;
2000
2001 if (kstrtoint(end, 10, &id) < 0)
2002 continue;
2003
2004 /* Allocate an alias_prop with enough space for the stem */
2005 ap = dt_alloc(sizeof(*ap) + len + 1, __alignof__(*ap));
2006 if (!ap)
2007 continue;
2008 memset(ap, 0, sizeof(*ap) + len + 1);
2009 ap->alias = start;
2010 of_alias_add(ap, np, id, start, len);
2011 }
2012}
2013
2014/**
2015 * of_alias_get_id - Get alias id for the given device_node
2016 * @np: Pointer to the given device_node
2017 * @stem: Alias stem of the given device_node
2018 *
2019 * The function travels the lookup table to get the alias id for the given
2020 * device_node and alias stem. It returns the alias id if found.
2021 */
2022int of_alias_get_id(struct device_node *np, const char *stem)
2023{
2024 struct alias_prop *app;
2025 int id = -ENODEV;
2026
2027 mutex_lock(&of_mutex);
2028 list_for_each_entry(app, &aliases_lookup, link) {
2029 if (strcmp(app->stem, stem) != 0)
2030 continue;
2031
2032 if (np == app->np) {
2033 id = app->id;
2034 break;
2035 }
2036 }
2037 mutex_unlock(&of_mutex);
2038
2039 return id;
2040}
2041EXPORT_SYMBOL_GPL(of_alias_get_id);
2042
2043/**
2044 * of_alias_get_alias_list - Get alias list for the given device driver
2045 * @matches: Array of OF device match structures to search in
2046 * @stem: Alias stem of the given device_node
2047 * @bitmap: Bitmap field pointer
2048 * @nbits: Maximum number of alias IDs which can be recorded in bitmap
2049 *
2050 * The function travels the lookup table to record alias ids for the given
2051 * device match structures and alias stem.
2052 *
2053 * Return: 0 or -ENOSYS when !CONFIG_OF or
2054 * -EOVERFLOW if alias ID is greater then allocated nbits
2055 */
2056int of_alias_get_alias_list(const struct of_device_id *matches,
2057 const char *stem, unsigned long *bitmap,
2058 unsigned int nbits)
2059{
2060 struct alias_prop *app;
2061 int ret = 0;
2062
2063 /* Zero bitmap field to make sure that all the time it is clean */
2064 bitmap_zero(bitmap, nbits);
2065
2066 mutex_lock(&of_mutex);
2067 pr_debug("%s: Looking for stem: %s\n", __func__, stem);
2068 list_for_each_entry(app, &aliases_lookup, link) {
2069 pr_debug("%s: stem: %s, id: %d\n",
2070 __func__, app->stem, app->id);
2071
2072 if (strcmp(app->stem, stem) != 0) {
2073 pr_debug("%s: stem comparison didn't pass %s\n",
2074 __func__, app->stem);
2075 continue;
2076 }
2077
2078 if (of_match_node(matches, app->np)) {
2079 pr_debug("%s: Allocated ID %d\n", __func__, app->id);
2080
2081 if (app->id >= nbits) {
2082 pr_warn("%s: ID %d >= than bitmap field %d\n",
2083 __func__, app->id, nbits);
2084 ret = -EOVERFLOW;
2085 } else {
2086 set_bit(app->id, bitmap);
2087 }
2088 }
2089 }
2090 mutex_unlock(&of_mutex);
2091
2092 return ret;
2093}
2094EXPORT_SYMBOL_GPL(of_alias_get_alias_list);
2095
2096/**
2097 * of_alias_get_highest_id - Get highest alias id for the given stem
2098 * @stem: Alias stem to be examined
2099 *
2100 * The function travels the lookup table to get the highest alias id for the
2101 * given alias stem. It returns the alias id if found.
2102 */
2103int of_alias_get_highest_id(const char *stem)
2104{
2105 struct alias_prop *app;
2106 int id = -ENODEV;
2107
2108 mutex_lock(&of_mutex);
2109 list_for_each_entry(app, &aliases_lookup, link) {
2110 if (strcmp(app->stem, stem) != 0)
2111 continue;
2112
2113 if (app->id > id)
2114 id = app->id;
2115 }
2116 mutex_unlock(&of_mutex);
2117
2118 return id;
2119}
2120EXPORT_SYMBOL_GPL(of_alias_get_highest_id);
2121
2122/**
2123 * of_console_check() - Test and setup console for DT setup
2124 * @dn - Pointer to device node
2125 * @name - Name to use for preferred console without index. ex. "ttyS"
2126 * @index - Index to use for preferred console.
2127 *
2128 * Check if the given device node matches the stdout-path property in the
2129 * /chosen node. If it does then register it as the preferred console and return
2130 * TRUE. Otherwise return FALSE.
2131 */
2132bool of_console_check(struct device_node *dn, char *name, int index)
2133{
2134 if (!dn || dn != of_stdout || console_set_on_cmdline)
2135 return false;
2136
2137 /*
2138 * XXX: cast `options' to char pointer to suppress complication
2139 * warnings: printk, UART and console drivers expect char pointer.
2140 */
2141 return !add_preferred_console(name, index, (char *)of_stdout_options);
2142}
2143EXPORT_SYMBOL_GPL(of_console_check);
2144
2145/**
2146 * of_find_next_cache_node - Find a node's subsidiary cache
2147 * @np: node of type "cpu" or "cache"
2148 *
2149 * Returns a node pointer with refcount incremented, use
2150 * of_node_put() on it when done. Caller should hold a reference
2151 * to np.
2152 */
2153struct device_node *of_find_next_cache_node(const struct device_node *np)
2154{
2155 struct device_node *child, *cache_node;
2156
2157 cache_node = of_parse_phandle(np, "l2-cache", 0);
2158 if (!cache_node)
2159 cache_node = of_parse_phandle(np, "next-level-cache", 0);
2160
2161 if (cache_node)
2162 return cache_node;
2163
2164 /* OF on pmac has nodes instead of properties named "l2-cache"
2165 * beneath CPU nodes.
2166 */
2167 if (IS_ENABLED(CONFIG_PPC_PMAC) && of_node_is_type(np, "cpu"))
2168 for_each_child_of_node(np, child)
2169 if (of_node_is_type(child, "cache"))
2170 return child;
2171
2172 return NULL;
2173}
2174
2175/**
2176 * of_find_last_cache_level - Find the level at which the last cache is
2177 * present for the given logical cpu
2178 *
2179 * @cpu: cpu number(logical index) for which the last cache level is needed
2180 *
2181 * Returns the the level at which the last cache is present. It is exactly
2182 * same as the total number of cache levels for the given logical cpu.
2183 */
2184int of_find_last_cache_level(unsigned int cpu)
2185{
2186 u32 cache_level = 0;
2187 struct device_node *prev = NULL, *np = of_cpu_device_node_get(cpu);
2188
2189 while (np) {
2190 prev = np;
2191 of_node_put(np);
2192 np = of_find_next_cache_node(np);
2193 }
2194
2195 of_property_read_u32(prev, "cache-level", &cache_level);
2196
2197 return cache_level;
2198}
2199
2200/**
2201 * of_map_rid - Translate a requester ID through a downstream mapping.
2202 * @np: root complex device node.
2203 * @rid: device requester ID to map.
2204 * @map_name: property name of the map to use.
2205 * @map_mask_name: optional property name of the mask to use.
2206 * @target: optional pointer to a target device node.
2207 * @id_out: optional pointer to receive the translated ID.
2208 *
2209 * Given a device requester ID, look up the appropriate implementation-defined
2210 * platform ID and/or the target device which receives transactions on that
2211 * ID, as per the "iommu-map" and "msi-map" bindings. Either of @target or
2212 * @id_out may be NULL if only the other is required. If @target points to
2213 * a non-NULL device node pointer, only entries targeting that node will be
2214 * matched; if it points to a NULL value, it will receive the device node of
2215 * the first matching target phandle, with a reference held.
2216 *
2217 * Return: 0 on success or a standard error code on failure.
2218 */
2219int of_map_rid(struct device_node *np, u32 rid,
2220 const char *map_name, const char *map_mask_name,
2221 struct device_node **target, u32 *id_out)
2222{
2223 u32 map_mask, masked_rid;
2224 int map_len;
2225 const __be32 *map = NULL;
2226
2227 if (!np || !map_name || (!target && !id_out))
2228 return -EINVAL;
2229
2230 map = of_get_property(np, map_name, &map_len);
2231 if (!map) {
2232 if (target)
2233 return -ENODEV;
2234 /* Otherwise, no map implies no translation */
2235 *id_out = rid;
2236 return 0;
2237 }
2238
2239 if (!map_len || map_len % (4 * sizeof(*map))) {
2240 pr_err("%pOF: Error: Bad %s length: %d\n", np,
2241 map_name, map_len);
2242 return -EINVAL;
2243 }
2244
2245 /* The default is to select all bits. */
2246 map_mask = 0xffffffff;
2247
2248 /*
2249 * Can be overridden by "{iommu,msi}-map-mask" property.
2250 * If of_property_read_u32() fails, the default is used.
2251 */
2252 if (map_mask_name)
2253 of_property_read_u32(np, map_mask_name, &map_mask);
2254
2255 masked_rid = map_mask & rid;
2256 for ( ; map_len > 0; map_len -= 4 * sizeof(*map), map += 4) {
2257 struct device_node *phandle_node;
2258 u32 rid_base = be32_to_cpup(map + 0);
2259 u32 phandle = be32_to_cpup(map + 1);
2260 u32 out_base = be32_to_cpup(map + 2);
2261 u32 rid_len = be32_to_cpup(map + 3);
2262
2263 if (rid_base & ~map_mask) {
2264 pr_err("%pOF: Invalid %s translation - %s-mask (0x%x) ignores rid-base (0x%x)\n",
2265 np, map_name, map_name,
2266 map_mask, rid_base);
2267 return -EFAULT;
2268 }
2269
2270 if (masked_rid < rid_base || masked_rid >= rid_base + rid_len)
2271 continue;
2272
2273 phandle_node = of_find_node_by_phandle(phandle);
2274 if (!phandle_node)
2275 return -ENODEV;
2276
2277 if (target) {
2278 if (*target)
2279 of_node_put(phandle_node);
2280 else
2281 *target = phandle_node;
2282
2283 if (*target != phandle_node)
2284 continue;
2285 }
2286
2287 if (id_out)
2288 *id_out = masked_rid - rid_base + out_base;
2289
2290 pr_debug("%pOF: %s, using mask %08x, rid-base: %08x, out-base: %08x, length: %08x, rid: %08x -> %08x\n",
2291 np, map_name, map_mask, rid_base, out_base,
2292 rid_len, rid, masked_rid - rid_base + out_base);
2293 return 0;
2294 }
2295
2296 pr_err("%pOF: Invalid %s translation - no match for rid 0x%x on %pOF\n",
2297 np, map_name, rid, target && *target ? *target : NULL);
2298 return -EFAULT;
2299}
2300EXPORT_SYMBOL_GPL(of_map_rid);
2301