1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Originally from Linux v4.9
4 * Paul Mackerras August 1996.
5 * Copyright (C) 1996-2005 Paul Mackerras.
6 *
7 * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
8 * {engebret|bergner}@us.ibm.com
9 *
10 * Adapted for sparc and sparc64 by David S. Miller davem@davemloft.net
11 *
12 * Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell and
13 * Grant Likely.
14 *
15 * Modified for U-Boot
16 * Copyright (c) 2017 Google, Inc
17 *
18 * This file follows drivers/of/base.c with functions in the same order as the
19 * Linux version.
20 */
21
22 #include <common.h>
23 #include <log.h>
24 #include <malloc.h>
25 #include <asm/global_data.h>
26 #include <linux/bug.h>
27 #include <linux/libfdt.h>
28 #include <dm/of_access.h>
29 #include <linux/ctype.h>
30 #include <linux/err.h>
31 #include <linux/ioport.h>
32
33 DECLARE_GLOBAL_DATA_PTR;
34
35 /* list of struct alias_prop aliases */
36 static LIST_HEAD(aliases_lookup);
37
38 /* "/aliaes" node */
39 static struct device_node *of_aliases;
40
41 /* "/chosen" node */
42 static struct device_node *of_chosen;
43
44 /* node pointed to by the stdout-path alias */
45 static struct device_node *of_stdout;
46
47 /* pointer to options given after the alias (separated by :) or NULL if none */
48 static const char *of_stdout_options;
49
50 /**
51 * struct alias_prop - Alias property in 'aliases' node
52 *
53 * The structure represents one alias property of 'aliases' node as
54 * an entry in aliases_lookup list.
55 *
56 * @link: List node to link the structure in aliases_lookup list
57 * @alias: Alias property name
58 * @np: Pointer to device_node that the alias stands for
59 * @id: Index value from end of alias name
60 * @stem: Alias string without the index
61 */
62 struct alias_prop {
63 struct list_head link;
64 const char *alias;
65 struct device_node *np;
66 int id;
67 char stem[0];
68 };
69
of_n_addr_cells(const struct device_node * np)70 int of_n_addr_cells(const struct device_node *np)
71 {
72 const __be32 *ip;
73
74 do {
75 if (np->parent)
76 np = np->parent;
77 ip = of_get_property(np, "#address-cells", NULL);
78 if (ip)
79 return be32_to_cpup(ip);
80 } while (np->parent);
81
82 /* No #address-cells property for the root node */
83 return OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
84 }
85
of_n_size_cells(const struct device_node * np)86 int of_n_size_cells(const struct device_node *np)
87 {
88 const __be32 *ip;
89
90 do {
91 if (np->parent)
92 np = np->parent;
93 ip = of_get_property(np, "#size-cells", NULL);
94 if (ip)
95 return be32_to_cpup(ip);
96 } while (np->parent);
97
98 /* No #size-cells property for the root node */
99 return OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
100 }
101
of_simple_addr_cells(const struct device_node * np)102 int of_simple_addr_cells(const struct device_node *np)
103 {
104 const __be32 *ip;
105
106 ip = of_get_property(np, "#address-cells", NULL);
107 if (ip)
108 return be32_to_cpup(ip);
109
110 /* Return a default of 2 to match fdt_address_cells()*/
111 return 2;
112 }
113
of_simple_size_cells(const struct device_node * np)114 int of_simple_size_cells(const struct device_node *np)
115 {
116 const __be32 *ip;
117
118 ip = of_get_property(np, "#size-cells", NULL);
119 if (ip)
120 return be32_to_cpup(ip);
121
122 /* Return a default of 2 to match fdt_size_cells()*/
123 return 2;
124 }
125
of_find_property(const struct device_node * np,const char * name,int * lenp)126 struct property *of_find_property(const struct device_node *np,
127 const char *name, int *lenp)
128 {
129 struct property *pp;
130
131 if (!np)
132 return NULL;
133
134 for (pp = np->properties; pp; pp = pp->next) {
135 if (strcmp(pp->name, name) == 0) {
136 if (lenp)
137 *lenp = pp->length;
138 break;
139 }
140 }
141 if (!pp && lenp)
142 *lenp = -FDT_ERR_NOTFOUND;
143
144 return pp;
145 }
146
of_find_all_nodes(struct device_node * prev)147 struct device_node *of_find_all_nodes(struct device_node *prev)
148 {
149 struct device_node *np;
150
151 if (!prev) {
152 np = gd->of_root;
153 } else if (prev->child) {
154 np = prev->child;
155 } else {
156 /*
157 * Walk back up looking for a sibling, or the end of the
158 * structure
159 */
160 np = prev;
161 while (np->parent && !np->sibling)
162 np = np->parent;
163 np = np->sibling; /* Might be null at the end of the tree */
164 }
165
166 return np;
167 }
168
of_get_property(const struct device_node * np,const char * name,int * lenp)169 const void *of_get_property(const struct device_node *np, const char *name,
170 int *lenp)
171 {
172 struct property *pp = of_find_property(np, name, lenp);
173
174 return pp ? pp->value : NULL;
175 }
176
of_get_first_property(const struct device_node * np)177 const struct property *of_get_first_property(const struct device_node *np)
178 {
179 if (!np)
180 return NULL;
181
182 return np->properties;
183 }
184
of_get_next_property(const struct device_node * np,const struct property * property)185 const struct property *of_get_next_property(const struct device_node *np,
186 const struct property *property)
187 {
188 if (!np)
189 return NULL;
190
191 return property->next;
192 }
193
of_get_property_by_prop(const struct device_node * np,const struct property * property,const char ** name,int * lenp)194 const void *of_get_property_by_prop(const struct device_node *np,
195 const struct property *property,
196 const char **name,
197 int *lenp)
198 {
199 if (!np || !property)
200 return NULL;
201 if (name)
202 *name = property->name;
203 if (lenp)
204 *lenp = property->length;
205
206 return property->value;
207 }
208
of_prop_next_string(struct property * prop,const char * cur)209 static const char *of_prop_next_string(struct property *prop, const char *cur)
210 {
211 const void *curv = cur;
212
213 if (!prop)
214 return NULL;
215
216 if (!cur)
217 return prop->value;
218
219 curv += strlen(cur) + 1;
220 if (curv >= prop->value + prop->length)
221 return NULL;
222
223 return curv;
224 }
225
of_device_is_compatible(const struct device_node * device,const char * compat,const char * type,const char * name)226 int of_device_is_compatible(const struct device_node *device,
227 const char *compat, const char *type,
228 const char *name)
229 {
230 struct property *prop;
231 const char *cp;
232 int index = 0, score = 0;
233
234 /* Compatible match has highest priority */
235 if (compat && compat[0]) {
236 prop = of_find_property(device, "compatible", NULL);
237 for (cp = of_prop_next_string(prop, NULL); cp;
238 cp = of_prop_next_string(prop, cp), index++) {
239 if (of_compat_cmp(cp, compat, strlen(compat)) == 0) {
240 score = INT_MAX/2 - (index << 2);
241 break;
242 }
243 }
244 if (!score)
245 return 0;
246 }
247
248 /* Matching type is better than matching name */
249 if (type && type[0]) {
250 if (!device->type || of_node_cmp(type, device->type))
251 return 0;
252 score += 2;
253 }
254
255 /* Matching name is a bit better than not */
256 if (name && name[0]) {
257 if (!device->name || of_node_cmp(name, device->name))
258 return 0;
259 score++;
260 }
261
262 return score;
263 }
264
of_device_is_available(const struct device_node * device)265 bool of_device_is_available(const struct device_node *device)
266 {
267 const char *status;
268 int statlen;
269
270 if (!device)
271 return false;
272
273 status = of_get_property(device, "status", &statlen);
274 if (status == NULL)
275 return true;
276
277 if (statlen > 0) {
278 if (!strcmp(status, "okay"))
279 return true;
280 }
281
282 return false;
283 }
284
of_get_parent(const struct device_node * node)285 struct device_node *of_get_parent(const struct device_node *node)
286 {
287 const struct device_node *np;
288
289 if (!node)
290 return NULL;
291
292 np = of_node_get(node->parent);
293
294 return (struct device_node *)np;
295 }
296
__of_get_next_child(const struct device_node * node,struct device_node * prev)297 static struct device_node *__of_get_next_child(const struct device_node *node,
298 struct device_node *prev)
299 {
300 struct device_node *next;
301
302 if (!node)
303 return NULL;
304
305 next = prev ? prev->sibling : node->child;
306 /*
307 * coverity[dead_error_line : FALSE]
308 * Dead code here since our current implementation of of_node_get()
309 * always returns NULL (Coverity CID 163245). But we leave it as is
310 * since we may want to implement get/put later.
311 */
312 for (; next; next = next->sibling)
313 if (of_node_get(next))
314 break;
315 of_node_put(prev);
316 return next;
317 }
318
319 #define __for_each_child_of_node(parent, child) \
320 for (child = __of_get_next_child(parent, NULL); child != NULL; \
321 child = __of_get_next_child(parent, child))
322
__of_find_node_by_path(struct device_node * parent,const char * path)323 static struct device_node *__of_find_node_by_path(struct device_node *parent,
324 const char *path)
325 {
326 struct device_node *child;
327 int len;
328
329 len = strcspn(path, "/:");
330 if (!len)
331 return NULL;
332
333 __for_each_child_of_node(parent, child) {
334 const char *name = strrchr(child->full_name, '/');
335
336 name++;
337 if (strncmp(path, name, len) == 0 && (strlen(name) == len))
338 return child;
339 }
340 return NULL;
341 }
342
343 #define for_each_property_of_node(dn, pp) \
344 for (pp = dn->properties; pp != NULL; pp = pp->next)
345
of_find_node_opts_by_path(struct device_node * root,const char * path,const char ** opts)346 struct device_node *of_find_node_opts_by_path(struct device_node *root,
347 const char *path,
348 const char **opts)
349 {
350 struct device_node *np = NULL;
351 struct property *pp;
352 const char *separator = strchr(path, ':');
353
354 if (!root)
355 root = gd->of_root;
356 if (opts)
357 *opts = separator ? separator + 1 : NULL;
358
359 if (strcmp(path, "/") == 0)
360 return of_node_get(root);
361
362 /* The path could begin with an alias */
363 if (*path != '/') {
364 int len;
365 const char *p = separator;
366
367 /* Only allow alias processing on the control FDT */
368 if (root != gd->of_root)
369 return NULL;
370 if (!p)
371 p = strchrnul(path, '/');
372 len = p - path;
373
374 /* of_aliases must not be NULL */
375 if (!of_aliases)
376 return NULL;
377
378 for_each_property_of_node(of_aliases, pp) {
379 if (strlen(pp->name) == len && !strncmp(pp->name, path,
380 len)) {
381 np = of_find_node_by_path(pp->value);
382 break;
383 }
384 }
385 if (!np)
386 return NULL;
387 path = p;
388 }
389
390 /* Step down the tree matching path components */
391 if (!np)
392 np = of_node_get(root);
393 while (np && *path == '/') {
394 struct device_node *tmp = np;
395
396 path++; /* Increment past '/' delimiter */
397 np = __of_find_node_by_path(np, path);
398 of_node_put(tmp);
399 path = strchrnul(path, '/');
400 if (separator && separator < path)
401 break;
402 }
403
404 return np;
405 }
406
of_find_compatible_node(struct device_node * from,const char * type,const char * compatible)407 struct device_node *of_find_compatible_node(struct device_node *from,
408 const char *type, const char *compatible)
409 {
410 struct device_node *np;
411
412 for_each_of_allnodes_from(from, np)
413 if (of_device_is_compatible(np, compatible, type, NULL) &&
414 of_node_get(np))
415 break;
416 of_node_put(from);
417
418 return np;
419 }
420
of_device_has_prop_value(const struct device_node * device,const char * propname,const void * propval,int proplen)421 static int of_device_has_prop_value(const struct device_node *device,
422 const char *propname, const void *propval,
423 int proplen)
424 {
425 struct property *prop = of_find_property(device, propname, NULL);
426
427 if (!prop || !prop->value || prop->length != proplen)
428 return 0;
429 return !memcmp(prop->value, propval, proplen);
430 }
431
of_find_node_by_prop_value(struct device_node * from,const char * propname,const void * propval,int proplen)432 struct device_node *of_find_node_by_prop_value(struct device_node *from,
433 const char *propname,
434 const void *propval, int proplen)
435 {
436 struct device_node *np;
437
438 for_each_of_allnodes_from(from, np) {
439 if (of_device_has_prop_value(np, propname, propval, proplen) &&
440 of_node_get(np))
441 break;
442 }
443 of_node_put(from);
444
445 return np;
446 }
447
of_find_node_by_phandle(struct device_node * root,phandle handle)448 struct device_node *of_find_node_by_phandle(struct device_node *root,
449 phandle handle)
450 {
451 struct device_node *np;
452
453 if (!handle)
454 return NULL;
455
456 for_each_of_allnodes_from(root, np)
457 if (np->phandle == handle)
458 break;
459 (void)of_node_get(np);
460
461 return np;
462 }
463
464 /**
465 * of_find_property_value_of_size() - find property of given size
466 *
467 * Search for a property in a device node and validate the requested size.
468 *
469 * @np: device node from which the property value is to be read.
470 * @propname: name of the property to be searched.
471 * @len: requested length of property value
472 *
473 * Return: the property value on success, -EINVAL if the property does not
474 * exist and -EOVERFLOW if the property data isn't large enough.
475 */
of_find_property_value_of_size(const struct device_node * np,const char * propname,u32 len)476 static void *of_find_property_value_of_size(const struct device_node *np,
477 const char *propname, u32 len)
478 {
479 struct property *prop = of_find_property(np, propname, NULL);
480
481 if (!prop)
482 return ERR_PTR(-EINVAL);
483 if (len > prop->length)
484 return ERR_PTR(-EOVERFLOW);
485
486 return prop->value;
487 }
488
of_read_u8(const struct device_node * np,const char * propname,u8 * outp)489 int of_read_u8(const struct device_node *np, const char *propname, u8 *outp)
490 {
491 const u8 *val;
492
493 debug("%s: %s: ", __func__, propname);
494 if (!np)
495 return -EINVAL;
496 val = of_find_property_value_of_size(np, propname, sizeof(*outp));
497 if (IS_ERR(val)) {
498 debug("(not found)\n");
499 return PTR_ERR(val);
500 }
501
502 *outp = *val;
503 debug("%#x (%d)\n", *outp, *outp);
504
505 return 0;
506 }
507
of_read_u16(const struct device_node * np,const char * propname,u16 * outp)508 int of_read_u16(const struct device_node *np, const char *propname, u16 *outp)
509 {
510 const __be16 *val;
511
512 debug("%s: %s: ", __func__, propname);
513 if (!np)
514 return -EINVAL;
515 val = of_find_property_value_of_size(np, propname, sizeof(*outp));
516 if (IS_ERR(val)) {
517 debug("(not found)\n");
518 return PTR_ERR(val);
519 }
520
521 *outp = be16_to_cpup(val);
522 debug("%#x (%d)\n", *outp, *outp);
523
524 return 0;
525 }
526
of_read_u32(const struct device_node * np,const char * propname,u32 * outp)527 int of_read_u32(const struct device_node *np, const char *propname, u32 *outp)
528 {
529 return of_read_u32_index(np, propname, 0, outp);
530 }
531
of_read_u32_array(const struct device_node * np,const char * propname,u32 * out_values,size_t sz)532 int of_read_u32_array(const struct device_node *np, const char *propname,
533 u32 *out_values, size_t sz)
534 {
535 const __be32 *val;
536
537 debug("%s: %s: ", __func__, propname);
538 val = of_find_property_value_of_size(np, propname,
539 sz * sizeof(*out_values));
540
541 if (IS_ERR(val))
542 return PTR_ERR(val);
543
544 debug("size %zd\n", sz);
545 while (sz--)
546 *out_values++ = be32_to_cpup(val++);
547
548 return 0;
549 }
550
of_read_u32_index(const struct device_node * np,const char * propname,int index,u32 * outp)551 int of_read_u32_index(const struct device_node *np, const char *propname,
552 int index, u32 *outp)
553 {
554 const __be32 *val;
555
556 debug("%s: %s: ", __func__, propname);
557 if (!np)
558 return -EINVAL;
559
560 val = of_find_property_value_of_size(np, propname,
561 sizeof(*outp) * (index + 1));
562 if (IS_ERR(val)) {
563 debug("(not found)\n");
564 return PTR_ERR(val);
565 }
566
567 *outp = be32_to_cpup(val + index);
568 debug("%#x (%d)\n", *outp, *outp);
569
570 return 0;
571 }
572
of_read_u64(const struct device_node * np,const char * propname,u64 * outp)573 int of_read_u64(const struct device_node *np, const char *propname, u64 *outp)
574 {
575 const __be64 *val;
576
577 debug("%s: %s: ", __func__, propname);
578 if (!np)
579 return -EINVAL;
580 val = of_find_property_value_of_size(np, propname, sizeof(*outp));
581 if (IS_ERR(val)) {
582 debug("(not found)\n");
583 return PTR_ERR(val);
584 }
585
586 *outp = be64_to_cpup(val);
587 debug("%#llx (%lld)\n", (unsigned long long)*outp,
588 (unsigned long long)*outp);
589
590 return 0;
591 }
592
of_property_match_string(const struct device_node * np,const char * propname,const char * string)593 int of_property_match_string(const struct device_node *np, const char *propname,
594 const char *string)
595 {
596 const struct property *prop = of_find_property(np, propname, NULL);
597 size_t l;
598 int i;
599 const char *p, *end;
600
601 if (!prop)
602 return -EINVAL;
603 if (!prop->value)
604 return -ENODATA;
605
606 p = prop->value;
607 end = p + prop->length;
608
609 for (i = 0; p < end; i++, p += l) {
610 l = strnlen(p, end - p) + 1;
611 if (p + l > end)
612 return -EILSEQ;
613 debug("comparing %s with %s\n", string, p);
614 if (strcmp(string, p) == 0)
615 return i; /* Found it; return index */
616 }
617 return -ENODATA;
618 }
619
620 /**
621 * of_property_read_string_helper() - Utility helper for parsing string properties
622 * @np: device node from which the property value is to be read.
623 * @propname: name of the property to be searched.
624 * @out_strs: output array of string pointers.
625 * @sz: number of array elements to read.
626 * @skip: Number of strings to skip over at beginning of list (cannot be
627 * negative)
628 *
629 * Don't call this function directly. It is a utility helper for the
630 * of_property_read_string*() family of functions.
631 */
of_property_read_string_helper(const struct device_node * np,const char * propname,const char ** out_strs,size_t sz,int skip)632 int of_property_read_string_helper(const struct device_node *np,
633 const char *propname, const char **out_strs,
634 size_t sz, int skip)
635 {
636 const struct property *prop = of_find_property(np, propname, NULL);
637 int l = 0, i = 0;
638 const char *p, *end;
639
640 if (!prop)
641 return -EINVAL;
642 if (!prop->value)
643 return -ENODATA;
644 p = prop->value;
645 end = p + prop->length;
646
647 for (i = 0; p < end && (!out_strs || i < skip + sz); i++, p += l) {
648 l = strnlen(p, end - p) + 1;
649 if (p + l > end)
650 return -EILSEQ;
651 if (out_strs && i >= skip)
652 *out_strs++ = p;
653 }
654 i -= skip;
655 return i <= 0 ? -ENODATA : i;
656 }
657
__of_parse_phandle_with_args(const struct device_node * np,const char * list_name,const char * cells_name,int cell_count,int index,struct of_phandle_args * out_args)658 static int __of_parse_phandle_with_args(const struct device_node *np,
659 const char *list_name,
660 const char *cells_name,
661 int cell_count, int index,
662 struct of_phandle_args *out_args)
663 {
664 const __be32 *list, *list_end;
665 int rc = 0, cur_index = 0;
666 uint32_t count;
667 struct device_node *node = NULL;
668 phandle phandle;
669 int size;
670
671 /* Retrieve the phandle list property */
672 list = of_get_property(np, list_name, &size);
673 if (!list)
674 return -ENOENT;
675 list_end = list + size / sizeof(*list);
676
677 /* Loop over the phandles until all the requested entry is found */
678 while (list < list_end) {
679 rc = -EINVAL;
680 count = 0;
681
682 /*
683 * If phandle is 0, then it is an empty entry with no
684 * arguments. Skip forward to the next entry.
685 */
686 phandle = be32_to_cpup(list++);
687 if (phandle) {
688 /*
689 * Find the provider node and parse the #*-cells
690 * property to determine the argument length.
691 *
692 * This is not needed if the cell count is hard-coded
693 * (i.e. cells_name not set, but cell_count is set),
694 * except when we're going to return the found node
695 * below.
696 */
697 if (cells_name || cur_index == index) {
698 node = of_find_node_by_phandle(NULL, phandle);
699 if (!node) {
700 debug("%s: could not find phandle\n",
701 np->full_name);
702 goto err;
703 }
704 }
705
706 if (cells_name) {
707 if (of_read_u32(node, cells_name, &count)) {
708 debug("%s: could not get %s for %s\n",
709 np->full_name, cells_name,
710 node->full_name);
711 goto err;
712 }
713 } else {
714 count = cell_count;
715 }
716
717 /*
718 * Make sure that the arguments actually fit in the
719 * remaining property data length
720 */
721 if (list + count > list_end) {
722 debug("%s: arguments longer than property\n",
723 np->full_name);
724 goto err;
725 }
726 }
727
728 /*
729 * All of the error cases above bail out of the loop, so at
730 * this point, the parsing is successful. If the requested
731 * index matches, then fill the out_args structure and return,
732 * or return -ENOENT for an empty entry.
733 */
734 rc = -ENOENT;
735 if (cur_index == index) {
736 if (!phandle)
737 goto err;
738
739 if (out_args) {
740 int i;
741 if (WARN_ON(count > OF_MAX_PHANDLE_ARGS))
742 count = OF_MAX_PHANDLE_ARGS;
743 out_args->np = node;
744 out_args->args_count = count;
745 for (i = 0; i < count; i++)
746 out_args->args[i] =
747 be32_to_cpup(list++);
748 } else {
749 of_node_put(node);
750 }
751
752 /* Found it! return success */
753 return 0;
754 }
755
756 of_node_put(node);
757 node = NULL;
758 list += count;
759 cur_index++;
760 }
761
762 /*
763 * Unlock node before returning result; will be one of:
764 * -ENOENT : index is for empty phandle
765 * -EINVAL : parsing error on data
766 * [1..n] : Number of phandle (count mode; when index = -1)
767 */
768 rc = index < 0 ? cur_index : -ENOENT;
769 err:
770 if (node)
771 of_node_put(node);
772 return rc;
773 }
774
of_parse_phandle(const struct device_node * np,const char * phandle_name,int index)775 struct device_node *of_parse_phandle(const struct device_node *np,
776 const char *phandle_name, int index)
777 {
778 struct of_phandle_args args;
779
780 if (index < 0)
781 return NULL;
782
783 if (__of_parse_phandle_with_args(np, phandle_name, NULL, 0, index,
784 &args))
785 return NULL;
786
787 return args.np;
788 }
789
of_parse_phandle_with_args(const struct device_node * np,const char * list_name,const char * cells_name,int cell_count,int index,struct of_phandle_args * out_args)790 int of_parse_phandle_with_args(const struct device_node *np,
791 const char *list_name, const char *cells_name,
792 int cell_count, int index,
793 struct of_phandle_args *out_args)
794 {
795 if (index < 0)
796 return -EINVAL;
797
798 return __of_parse_phandle_with_args(np, list_name, cells_name,
799 cell_count, index, out_args);
800 }
801
of_count_phandle_with_args(const struct device_node * np,const char * list_name,const char * cells_name,int cell_count)802 int of_count_phandle_with_args(const struct device_node *np,
803 const char *list_name, const char *cells_name,
804 int cell_count)
805 {
806 return __of_parse_phandle_with_args(np, list_name, cells_name,
807 cell_count, -1, NULL);
808 }
809
of_alias_add(struct alias_prop * ap,struct device_node * np,int id,const char * stem,int stem_len)810 static void of_alias_add(struct alias_prop *ap, struct device_node *np,
811 int id, const char *stem, int stem_len)
812 {
813 ap->np = np;
814 ap->id = id;
815 strncpy(ap->stem, stem, stem_len);
816 ap->stem[stem_len] = 0;
817 list_add_tail(&ap->link, &aliases_lookup);
818 debug("adding DT alias:%s: stem=%s id=%i node=%s\n",
819 ap->alias, ap->stem, ap->id, of_node_full_name(np));
820 }
821
of_alias_scan(void)822 int of_alias_scan(void)
823 {
824 struct property *pp;
825
826 of_aliases = of_find_node_by_path("/aliases");
827 of_chosen = of_find_node_by_path("/chosen");
828 if (of_chosen == NULL)
829 of_chosen = of_find_node_by_path("/chosen@0");
830
831 if (of_chosen) {
832 const char *name;
833
834 name = of_get_property(of_chosen, "stdout-path", NULL);
835 if (name)
836 of_stdout = of_find_node_opts_by_path(NULL, name,
837 &of_stdout_options);
838 }
839
840 if (!of_aliases)
841 return 0;
842
843 for_each_property_of_node(of_aliases, pp) {
844 const char *start = pp->name;
845 const char *end = start + strlen(start);
846 struct device_node *np;
847 struct alias_prop *ap;
848 ulong id;
849 int len;
850
851 /* Skip those we do not want to proceed */
852 if (!strcmp(pp->name, "name") ||
853 !strcmp(pp->name, "phandle") ||
854 !strcmp(pp->name, "linux,phandle"))
855 continue;
856
857 np = of_find_node_by_path(pp->value);
858 if (!np)
859 continue;
860
861 /*
862 * walk the alias backwards to extract the id and work out
863 * the 'stem' string
864 */
865 while (isdigit(*(end-1)) && end > start)
866 end--;
867 len = end - start;
868
869 if (strict_strtoul(end, 10, &id) < 0)
870 continue;
871
872 /* Allocate an alias_prop with enough space for the stem */
873 ap = malloc(sizeof(*ap) + len + 1);
874 if (!ap)
875 return -ENOMEM;
876 memset(ap, 0, sizeof(*ap) + len + 1);
877 ap->alias = start;
878 of_alias_add(ap, np, id, start, len);
879 }
880
881 return 0;
882 }
883
of_alias_get_id(const struct device_node * np,const char * stem)884 int of_alias_get_id(const struct device_node *np, const char *stem)
885 {
886 struct alias_prop *app;
887 int id = -ENODEV;
888
889 mutex_lock(&of_mutex);
890 list_for_each_entry(app, &aliases_lookup, link) {
891 if (strcmp(app->stem, stem) != 0)
892 continue;
893
894 if (np == app->np) {
895 id = app->id;
896 break;
897 }
898 }
899 mutex_unlock(&of_mutex);
900
901 return id;
902 }
903
of_alias_get_highest_id(const char * stem)904 int of_alias_get_highest_id(const char *stem)
905 {
906 struct alias_prop *app;
907 int id = -1;
908
909 mutex_lock(&of_mutex);
910 list_for_each_entry(app, &aliases_lookup, link) {
911 if (strcmp(app->stem, stem) != 0)
912 continue;
913
914 if (app->id > id)
915 id = app->id;
916 }
917 mutex_unlock(&of_mutex);
918
919 return id;
920 }
921
of_get_stdout(void)922 struct device_node *of_get_stdout(void)
923 {
924 return of_stdout;
925 }
926
of_write_prop(struct device_node * np,const char * propname,int len,const void * value)927 int of_write_prop(struct device_node *np, const char *propname, int len,
928 const void *value)
929 {
930 struct property *pp;
931 struct property *pp_last = NULL;
932 struct property *new;
933
934 if (!np)
935 return -EINVAL;
936
937 for (pp = np->properties; pp; pp = pp->next) {
938 if (strcmp(pp->name, propname) == 0) {
939 /* Property exists -> change value */
940 pp->value = (void *)value;
941 pp->length = len;
942 return 0;
943 }
944 pp_last = pp;
945 }
946
947 /* Property does not exist -> append new property */
948 new = malloc(sizeof(struct property));
949 if (!new)
950 return -ENOMEM;
951
952 new->name = strdup(propname);
953 if (!new->name) {
954 free(new);
955 return -ENOMEM;
956 }
957
958 new->value = (void *)value;
959 new->length = len;
960 new->next = NULL;
961
962 if (pp_last)
963 pp_last->next = new;
964 else
965 np->properties = new;
966
967 return 0;
968 }
969
of_add_subnode(struct device_node * parent,const char * name,int len,struct device_node ** childp)970 int of_add_subnode(struct device_node *parent, const char *name, int len,
971 struct device_node **childp)
972 {
973 struct device_node *child, *new, *last_sibling = NULL;
974 char *new_name, *full_name;
975 int parent_fnl;
976
977 if (len == -1)
978 len = strlen(name);
979 __for_each_child_of_node(parent, child) {
980 /*
981 * make sure we don't use a child called "trevor" when we are
982 * searching for "trev".
983 */
984 if (!strncmp(child->name, name, len) && strlen(name) == len) {
985 *childp = child;
986 return -EEXIST;
987 }
988 last_sibling = child;
989 }
990
991 /* Subnode does not exist -> append new subnode */
992 new = calloc(1, sizeof(struct device_node));
993 if (!new)
994 return -ENOMEM;
995
996 new_name = memdup(name, len + 1);
997 if (!new_name) {
998 free(new);
999 return -ENOMEM;
1000 }
1001 new_name[len] = '\0';
1002
1003 /*
1004 * if the parent is the root node (named "") we don't need to prepend
1005 * its full path
1006 */
1007 parent_fnl = *parent->name ? strlen(parent->full_name) : 0;
1008 full_name = calloc(1, parent_fnl + 1 + len + 1);
1009 if (!full_name) {
1010 free(new_name);
1011 free(new);
1012 return -ENOMEM;
1013 }
1014 new->name = new_name; /* assign to constant pointer */
1015
1016 strcpy(full_name, parent->full_name); /* "" for root node */
1017 full_name[parent_fnl] = '/';
1018 strlcpy(&full_name[parent_fnl + 1], name, len + 1);
1019 new->full_name = full_name;
1020
1021 /* Add as last sibling of the parent */
1022 if (last_sibling)
1023 last_sibling->sibling = new;
1024 if (!parent->child)
1025 parent->child = new;
1026 new->parent = parent;
1027
1028 *childp = new;
1029
1030 return 0;
1031 }
1032