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7#include "libfdt_env.h"
8
9#include <fdt.h>
10#include <libfdt.h>
11
12#include "libfdt_internal.h"
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27
28static uint32_t overlay_get_target_phandle(const void *fdto, int fragment)
29{
30 const fdt32_t *val;
31 int len;
32
33 val = fdt_getprop(fdto, fragment, "target", &len);
34 if (!val)
35 return 0;
36
37 if ((len != sizeof(*val)) || (fdt32_to_cpu(*val) == (uint32_t)-1))
38 return (uint32_t)-1;
39
40 return fdt32_to_cpu(*val);
41}
42
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56
57
58static int overlay_get_target(const void *fdt, const void *fdto,
59 int fragment, char const **pathp)
60{
61 uint32_t phandle;
62 const char *path = NULL;
63 int path_len = 0, ret;
64
65
66 phandle = overlay_get_target_phandle(fdto, fragment);
67 if (phandle == (uint32_t)-1)
68 return -FDT_ERR_BADPHANDLE;
69
70
71 if (!phandle) {
72
73 path = fdt_getprop(fdto, fragment, "target-path", &path_len);
74 if (path)
75 ret = fdt_path_offset(fdt, path);
76 else
77 ret = path_len;
78 } else
79 ret = fdt_node_offset_by_phandle(fdt, phandle);
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81
82
83
84
85
86
87
88 if (ret < 0 && path_len == -FDT_ERR_NOTFOUND)
89 ret = -FDT_ERR_BADOVERLAY;
90
91
92 if (ret < 0)
93 return ret;
94
95
96 if (pathp)
97 *pathp = path ? path : NULL;
98
99 return ret;
100}
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115
116static int overlay_phandle_add_offset(void *fdt, int node,
117 const char *name, uint32_t delta)
118{
119 const fdt32_t *val;
120 uint32_t adj_val;
121 int len;
122
123 val = fdt_getprop(fdt, node, name, &len);
124 if (!val)
125 return len;
126
127 if (len != sizeof(*val))
128 return -FDT_ERR_BADPHANDLE;
129
130 adj_val = fdt32_to_cpu(*val);
131 if ((adj_val + delta) < adj_val)
132 return -FDT_ERR_NOPHANDLES;
133
134 adj_val += delta;
135 if (adj_val == (uint32_t)-1)
136 return -FDT_ERR_NOPHANDLES;
137
138 return fdt_setprop_inplace_u32(fdt, node, name, adj_val);
139}
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155
156static int overlay_adjust_node_phandles(void *fdto, int node,
157 uint32_t delta)
158{
159 int child;
160 int ret;
161
162 ret = overlay_phandle_add_offset(fdto, node, "phandle", delta);
163 if (ret && ret != -FDT_ERR_NOTFOUND)
164 return ret;
165
166 ret = overlay_phandle_add_offset(fdto, node, "linux,phandle", delta);
167 if (ret && ret != -FDT_ERR_NOTFOUND)
168 return ret;
169
170 fdt_for_each_subnode(child, fdto, node) {
171 ret = overlay_adjust_node_phandles(fdto, child, delta);
172 if (ret)
173 return ret;
174 }
175
176 return 0;
177}
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192
193static int overlay_adjust_local_phandles(void *fdto, uint32_t delta)
194{
195
196
197
198 return overlay_adjust_node_phandles(fdto, 0, delta);
199}
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219
220static int overlay_update_local_node_references(void *fdto,
221 int tree_node,
222 int fixup_node,
223 uint32_t delta)
224{
225 int fixup_prop;
226 int fixup_child;
227 int ret;
228
229 fdt_for_each_property_offset(fixup_prop, fdto, fixup_node) {
230 const fdt32_t *fixup_val;
231 const char *tree_val;
232 const char *name;
233 int fixup_len;
234 int tree_len;
235 int i;
236
237 fixup_val = fdt_getprop_by_offset(fdto, fixup_prop,
238 &name, &fixup_len);
239 if (!fixup_val)
240 return fixup_len;
241
242 if (fixup_len % sizeof(uint32_t))
243 return -FDT_ERR_BADOVERLAY;
244 fixup_len /= sizeof(uint32_t);
245
246 tree_val = fdt_getprop(fdto, tree_node, name, &tree_len);
247 if (!tree_val) {
248 if (tree_len == -FDT_ERR_NOTFOUND)
249 return -FDT_ERR_BADOVERLAY;
250
251 return tree_len;
252 }
253
254 for (i = 0; i < fixup_len; i++) {
255 fdt32_t adj_val;
256 uint32_t poffset;
257
258 poffset = fdt32_to_cpu(fixup_val[i]);
259
260
261
262
263
264
265
266 memcpy(&adj_val, tree_val + poffset, sizeof(adj_val));
267
268 adj_val = cpu_to_fdt32(fdt32_to_cpu(adj_val) + delta);
269
270 ret = fdt_setprop_inplace_namelen_partial(fdto,
271 tree_node,
272 name,
273 strlen(name),
274 poffset,
275 &adj_val,
276 sizeof(adj_val));
277 if (ret == -FDT_ERR_NOSPACE)
278 return -FDT_ERR_BADOVERLAY;
279
280 if (ret)
281 return ret;
282 }
283 }
284
285 fdt_for_each_subnode(fixup_child, fdto, fixup_node) {
286 const char *fixup_child_name = fdt_get_name(fdto, fixup_child,
287 NULL);
288 int tree_child;
289
290 tree_child = fdt_subnode_offset(fdto, tree_node,
291 fixup_child_name);
292 if (tree_child == -FDT_ERR_NOTFOUND)
293 return -FDT_ERR_BADOVERLAY;
294 if (tree_child < 0)
295 return tree_child;
296
297 ret = overlay_update_local_node_references(fdto,
298 tree_child,
299 fixup_child,
300 delta);
301 if (ret)
302 return ret;
303 }
304
305 return 0;
306}
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324
325static int overlay_update_local_references(void *fdto, uint32_t delta)
326{
327 int fixups;
328
329 fixups = fdt_path_offset(fdto, "/__local_fixups__");
330 if (fixups < 0) {
331
332 if (fixups == -FDT_ERR_NOTFOUND)
333 return 0;
334
335 return fixups;
336 }
337
338
339
340
341 return overlay_update_local_node_references(fdto, 0, fixups,
342 delta);
343}
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368static int overlay_fixup_one_phandle(void *fdt, void *fdto,
369 int symbols_off,
370 const char *path, uint32_t path_len,
371 const char *name, uint32_t name_len,
372 int poffset, const char *label)
373{
374 const char *symbol_path;
375 uint32_t phandle;
376 fdt32_t phandle_prop;
377 int symbol_off, fixup_off;
378 int prop_len;
379
380 if (symbols_off < 0)
381 return symbols_off;
382
383 symbol_path = fdt_getprop(fdt, symbols_off, label,
384 &prop_len);
385 if (!symbol_path)
386 return prop_len;
387
388 symbol_off = fdt_path_offset(fdt, symbol_path);
389 if (symbol_off < 0)
390 return symbol_off;
391
392 phandle = fdt_get_phandle(fdt, symbol_off);
393 if (!phandle)
394 return -FDT_ERR_NOTFOUND;
395
396 fixup_off = fdt_path_offset_namelen(fdto, path, path_len);
397 if (fixup_off == -FDT_ERR_NOTFOUND)
398 return -FDT_ERR_BADOVERLAY;
399 if (fixup_off < 0)
400 return fixup_off;
401
402 phandle_prop = cpu_to_fdt32(phandle);
403 return fdt_setprop_inplace_namelen_partial(fdto, fixup_off,
404 name, name_len, poffset,
405 &phandle_prop,
406 sizeof(phandle_prop));
407};
408
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427
428static int overlay_fixup_phandle(void *fdt, void *fdto, int symbols_off,
429 int property)
430{
431 const char *value;
432 const char *label;
433 int len;
434
435 value = fdt_getprop_by_offset(fdto, property,
436 &label, &len);
437 if (!value) {
438 if (len == -FDT_ERR_NOTFOUND)
439 return -FDT_ERR_INTERNAL;
440
441 return len;
442 }
443
444 do {
445 const char *path, *name, *fixup_end;
446 const char *fixup_str = value;
447 uint32_t path_len, name_len;
448 uint32_t fixup_len;
449 char *sep, *endptr;
450 int poffset, ret;
451
452 fixup_end = memchr(value, '\0', len);
453 if (!fixup_end)
454 return -FDT_ERR_BADOVERLAY;
455 fixup_len = fixup_end - fixup_str;
456
457 len -= fixup_len + 1;
458 value += fixup_len + 1;
459
460 path = fixup_str;
461 sep = memchr(fixup_str, ':', fixup_len);
462 if (!sep || *sep != ':')
463 return -FDT_ERR_BADOVERLAY;
464
465 path_len = sep - path;
466 if (path_len == (fixup_len - 1))
467 return -FDT_ERR_BADOVERLAY;
468
469 fixup_len -= path_len + 1;
470 name = sep + 1;
471 sep = memchr(name, ':', fixup_len);
472 if (!sep || *sep != ':')
473 return -FDT_ERR_BADOVERLAY;
474
475 name_len = sep - name;
476 if (!name_len)
477 return -FDT_ERR_BADOVERLAY;
478
479 poffset = strtoul(sep + 1, &endptr, 10);
480 if ((*endptr != '\0') || (endptr <= (sep + 1)))
481 return -FDT_ERR_BADOVERLAY;
482
483 ret = overlay_fixup_one_phandle(fdt, fdto, symbols_off,
484 path, path_len, name, name_len,
485 poffset, label);
486 if (ret)
487 return ret;
488 } while (len > 0);
489
490 return 0;
491}
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509
510static int overlay_fixup_phandles(void *fdt, void *fdto)
511{
512 int fixups_off, symbols_off;
513 int property;
514
515
516 fixups_off = fdt_path_offset(fdto, "/__fixups__");
517 if (fixups_off == -FDT_ERR_NOTFOUND)
518 return 0;
519 if (fixups_off < 0)
520 return fixups_off;
521
522
523 symbols_off = fdt_path_offset(fdt, "/__symbols__");
524 if ((symbols_off < 0 && (symbols_off != -FDT_ERR_NOTFOUND)))
525 return symbols_off;
526
527 fdt_for_each_property_offset(property, fdto, fixups_off) {
528 int ret;
529
530 ret = overlay_fixup_phandle(fdt, fdto, symbols_off, property);
531 if (ret)
532 return ret;
533 }
534
535 return 0;
536}
537
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556
557static int overlay_apply_node(void *fdt, int target,
558 void *fdto, int node)
559{
560 int property;
561 int subnode;
562
563 fdt_for_each_property_offset(property, fdto, node) {
564 const char *name;
565 const void *prop;
566 int prop_len;
567 int ret;
568
569 prop = fdt_getprop_by_offset(fdto, property, &name,
570 &prop_len);
571 if (prop_len == -FDT_ERR_NOTFOUND)
572 return -FDT_ERR_INTERNAL;
573 if (prop_len < 0)
574 return prop_len;
575
576 ret = fdt_setprop(fdt, target, name, prop, prop_len);
577 if (ret)
578 return ret;
579 }
580
581 fdt_for_each_subnode(subnode, fdto, node) {
582 const char *name = fdt_get_name(fdto, subnode, NULL);
583 int nnode;
584 int ret;
585
586 nnode = fdt_add_subnode(fdt, target, name);
587 if (nnode == -FDT_ERR_EXISTS) {
588 nnode = fdt_subnode_offset(fdt, target, name);
589 if (nnode == -FDT_ERR_NOTFOUND)
590 return -FDT_ERR_INTERNAL;
591 }
592
593 if (nnode < 0)
594 return nnode;
595
596 ret = overlay_apply_node(fdt, nnode, fdto, subnode);
597 if (ret)
598 return ret;
599 }
600
601 return 0;
602}
603
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618
619static int overlay_merge(void *fdt, void *fdto)
620{
621 int fragment;
622
623 fdt_for_each_subnode(fragment, fdto, 0) {
624 int overlay;
625 int target;
626 int ret;
627
628
629
630
631
632 overlay = fdt_subnode_offset(fdto, fragment, "__overlay__");
633 if (overlay == -FDT_ERR_NOTFOUND)
634 continue;
635
636 if (overlay < 0)
637 return overlay;
638
639 target = overlay_get_target(fdt, fdto, fragment, NULL);
640 if (target < 0)
641 return target;
642
643 ret = overlay_apply_node(fdt, target, fdto, overlay);
644 if (ret)
645 return ret;
646 }
647
648 return 0;
649}
650
651static int get_path_len(const void *fdt, int nodeoffset)
652{
653 int len = 0, namelen;
654 const char *name;
655
656 FDT_RO_PROBE(fdt);
657
658 for (;;) {
659 name = fdt_get_name(fdt, nodeoffset, &namelen);
660 if (!name)
661 return namelen;
662
663
664 if (namelen == 0)
665 break;
666
667 nodeoffset = fdt_parent_offset(fdt, nodeoffset);
668 if (nodeoffset < 0)
669 return nodeoffset;
670 len += namelen + 1;
671 }
672
673
674 if (len == 0)
675 len++;
676 return len;
677}
678
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694
695static int overlay_symbol_update(void *fdt, void *fdto)
696{
697 int root_sym, ov_sym, prop, path_len, fragment, target;
698 int len, frag_name_len, ret, rel_path_len;
699 const char *s, *e;
700 const char *path;
701 const char *name;
702 const char *frag_name;
703 const char *rel_path;
704 const char *target_path;
705 char *buf;
706 void *p;
707
708 ov_sym = fdt_subnode_offset(fdto, 0, "__symbols__");
709
710
711 if (ov_sym < 0)
712 return 0;
713
714 root_sym = fdt_subnode_offset(fdt, 0, "__symbols__");
715
716
717 if (root_sym == -FDT_ERR_NOTFOUND)
718 root_sym = fdt_add_subnode(fdt, 0, "__symbols__");
719
720
721 if (root_sym < 0)
722 return root_sym;
723
724
725 fdt_for_each_property_offset(prop, fdto, ov_sym) {
726 path = fdt_getprop_by_offset(fdto, prop, &name, &path_len);
727 if (!path)
728 return path_len;
729
730
731 if (path_len < 1 || memchr(path, '\0', path_len) != &path[path_len - 1])
732 return -FDT_ERR_BADVALUE;
733
734
735 e = path + path_len;
736
737 if (*path != '/')
738 return -FDT_ERR_BADVALUE;
739
740
741 s = strchr(path + 1, '/');
742 if (!s) {
743
744
745 continue;
746 }
747
748 frag_name = path + 1;
749 frag_name_len = s - path - 1;
750
751
752 len = sizeof("/__overlay__/") - 1;
753 if ((e - s) > len && (memcmp(s, "/__overlay__/", len) == 0)) {
754
755 rel_path = s + len;
756 rel_path_len = e - rel_path;
757 } else if ((e - s) == len
758 && (memcmp(s, "/__overlay__", len - 1) == 0)) {
759
760 rel_path = "";
761 rel_path_len = 1;
762 } else {
763
764
765 continue;
766 }
767
768
769 ret = fdt_subnode_offset_namelen(fdto, 0, frag_name,
770 frag_name_len);
771
772 if (ret < 0)
773 return -FDT_ERR_BADOVERLAY;
774 fragment = ret;
775
776
777 ret = fdt_subnode_offset(fdto, fragment, "__overlay__");
778 if (ret < 0)
779 return -FDT_ERR_BADOVERLAY;
780
781
782 ret = overlay_get_target(fdt, fdto, fragment, &target_path);
783 if (ret < 0)
784 return ret;
785 target = ret;
786
787
788 if (!target_path) {
789 ret = get_path_len(fdt, target);
790 if (ret < 0)
791 return ret;
792 len = ret;
793 } else {
794 len = strlen(target_path);
795 }
796
797 ret = fdt_setprop_placeholder(fdt, root_sym, name,
798 len + (len > 1) + rel_path_len, &p);
799 if (ret < 0)
800 return ret;
801
802 if (!target_path) {
803
804 ret = overlay_get_target(fdt, fdto, fragment, &target_path);
805 if (ret < 0)
806 return ret;
807 target = ret;
808 }
809
810 buf = p;
811 if (len > 1) {
812 if (!target_path) {
813 ret = fdt_get_path(fdt, target, buf, len + 1);
814 if (ret < 0)
815 return ret;
816 } else
817 memcpy(buf, target_path, len + 1);
818
819 } else
820 len--;
821
822 buf[len] = '/';
823 memcpy(buf + len + 1, rel_path, rel_path_len);
824 }
825
826 return 0;
827}
828
829int fdt_overlay_apply(void *fdt, void *fdto)
830{
831 uint32_t delta;
832 int ret;
833
834 FDT_RO_PROBE(fdt);
835 FDT_RO_PROBE(fdto);
836
837 ret = fdt_find_max_phandle(fdt, &delta);
838 if (ret)
839 goto err;
840
841 ret = overlay_adjust_local_phandles(fdto, delta);
842 if (ret)
843 goto err;
844
845 ret = overlay_update_local_references(fdto, delta);
846 if (ret)
847 goto err;
848
849 ret = overlay_fixup_phandles(fdt, fdto);
850 if (ret)
851 goto err;
852
853 ret = overlay_merge(fdt, fdto);
854 if (ret)
855 goto err;
856
857 ret = overlay_symbol_update(fdt, fdto);
858 if (ret)
859 goto err;
860
861
862
863
864 fdt_set_magic(fdto, ~0);
865
866 return 0;
867
868err:
869
870
871
872 fdt_set_magic(fdto, ~0);
873
874
875
876
877
878 fdt_set_magic(fdt, ~0);
879
880 return ret;
881}
882
883int fdt_overlay_apply_node(void *fdt, int target, void *fdto, int node)
884{
885 return overlay_apply_node(fdt, target, fdto, node);
886}
887