1 // SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
3  * libfdt - Flat Device Tree manipulation
15  * overlay_get_target_phandle - retrieves the target phandle of a fragment
17  * @fragment: node offset of the fragment in the overlay
20  * overlay fragment when that fragment uses a phandle (target
21  * property) instead of a path (target-path property).
24  *      the phandle pointed by the target property
26  *	-1, if the phandle was malformed
37 	if ((len != sizeof(*val)) || (fdt32_to_cpu(*val) == (uint32_t)-1))  in overlay_get_target_phandle()
38 		return (uint32_t)-1;  in overlay_get_target_phandle()
44  * overlay_get_target - retrieves the offset of a fragment's target
47  * @fragment: node offset of the fragment in the overlay
51  * device tree of a fragment, no matter how the actual targeting is
52  * done (through a phandle or a path)
55  *      the targeted node offset in the base device tree
65 	/* Try first to do a phandle based lookup */  in overlay_get_target()
67 	if (phandle == (uint32_t)-1)  in overlay_get_target()
68 		return -FDT_ERR_BADPHANDLE;  in overlay_get_target()
72 		/* And then a path based lookup */  in overlay_get_target()
73 		path = fdt_getprop(fdto, fragment, "target-path", &path_len);  in overlay_get_target()
82 	* If we haven't found either a target or a  in overlay_get_target()
83 	* target-path property in a node that contains a  in overlay_get_target()
85 	* otherwise), consider it a improperly written  in overlay_get_target()
88 	if (ret < 0 && path_len == -FDT_ERR_NOTFOUND)  in overlay_get_target()
89 		ret = -FDT_ERR_BADOVERLAY;  in overlay_get_target()
103  * overlay_phandle_add_offset - Increases a phandle by an offset
105  * @node: Device tree overlay blob
106  * @name: Name of the property to modify (phandle or linux,phandle)
109  * overlay_phandle_add_offset() increments a node phandle by a given
116 static int overlay_phandle_add_offset(void *fdt, int node,  in overlay_phandle_add_offset()  argument
123 	val = fdt_getprop(fdt, node, name, &len);  in overlay_phandle_add_offset()
128 		return -FDT_ERR_BADPHANDLE;  in overlay_phandle_add_offset()
132 		return -FDT_ERR_NOPHANDLES;  in overlay_phandle_add_offset()
135 	if (adj_val == (uint32_t)-1)  in overlay_phandle_add_offset()
136 		return -FDT_ERR_NOPHANDLES;  in overlay_phandle_add_offset()
138 	return fdt_setprop_inplace_u32(fdt, node, name, adj_val);  in overlay_phandle_add_offset()
142  * overlay_adjust_node_phandles - Offsets the phandles of a node
144  * @node: Offset of the node we want to adjust
147  * overlay_adjust_node_phandles() adds a constant to all the phandles
148  * of a given node. This is mainly use as part of the overlay
156 static int overlay_adjust_node_phandles(void *fdto, int node,  in overlay_adjust_node_phandles()  argument
159 	int child;  in overlay_adjust_node_phandles()  local
162 	ret = overlay_phandle_add_offset(fdto, node, "phandle", delta);  in overlay_adjust_node_phandles()
163 	if (ret && ret != -FDT_ERR_NOTFOUND)  in overlay_adjust_node_phandles()
166 	ret = overlay_phandle_add_offset(fdto, node, "linux,phandle", delta);  in overlay_adjust_node_phandles()
167 	if (ret && ret != -FDT_ERR_NOTFOUND)  in overlay_adjust_node_phandles()
170 	fdt_for_each_subnode(child, fdto, node) {  in overlay_adjust_node_phandles()
171 		ret = overlay_adjust_node_phandles(fdto, child, delta);  in overlay_adjust_node_phandles()
180  * overlay_adjust_local_phandles - Adjust the phandles of a whole overlay
184  * overlay_adjust_local_phandles() adds a constant to all the
202  * overlay_update_local_node_references - Adjust the overlay references
204  * @tree_node: Node offset of the node to operate on
205  * @fixup_node: Node offset of the matching local fixups node
209  * pointing to a node within the device tree overlay by adding a
212  * This is mainly used as part of a device tree application process,
243 			return -FDT_ERR_BADOVERLAY;  in overlay_update_local_node_references()
248 			if (tree_len == -FDT_ERR_NOTFOUND)  in overlay_update_local_node_references()
249 				return -FDT_ERR_BADOVERLAY;  in overlay_update_local_node_references()
263 			 * Use a memcpy for the architectures that do  in overlay_update_local_node_references()
277 			if (ret == -FDT_ERR_NOSPACE)  in overlay_update_local_node_references()
278 				return -FDT_ERR_BADOVERLAY;  in overlay_update_local_node_references()
292 		if (tree_child == -FDT_ERR_NOTFOUND)  in overlay_update_local_node_references()
293 			return -FDT_ERR_BADOVERLAY;  in overlay_update_local_node_references()
309  * overlay_update_local_references - Adjust the overlay references
314  * to a node within the device tree overlay by adding a constant
317  * This is mainly used as part of a device tree application process,
332 		if (fixups == -FDT_ERR_NOTFOUND)  in overlay_update_local_references()
346  * overlay_fixup_one_phandle - Set an overlay phandle to the base one
349  * @symbols_off: Node offset of the symbols node in the base device tree
350  * @path: Path to a node holding a phandle in the overlay
352  * @name: Name of the property holding the phandle reference in the overlay
354  * @poffset: Offset within the overlay property where the phandle is stored
355  * @label: Label of the node referenced by the phandle
358  * a node in the base device tree.
394 		return -FDT_ERR_NOTFOUND;  in overlay_fixup_one_phandle()
397 	if (fixup_off == -FDT_ERR_NOTFOUND)  in overlay_fixup_one_phandle()
398 		return -FDT_ERR_BADOVERLAY;  in overlay_fixup_one_phandle()
410  * overlay_fixup_phandle - Set an overlay phandle to the base one
413  * @symbols_off: Node offset of the symbols node in the base device tree
414  * @property: Property offset in the overlay holding the list of fixups
417  * to in a __fixups__ property, and updates them to match the phandles
429 				 int property)  in overlay_fixup_phandle()  argument
435 	value = fdt_getprop_by_offset(fdto, property,  in overlay_fixup_phandle()
438 		if (len == -FDT_ERR_NOTFOUND)  in overlay_fixup_phandle()
439 			return -FDT_ERR_INTERNAL;  in overlay_fixup_phandle()
454 			return -FDT_ERR_BADOVERLAY;  in overlay_fixup_phandle()
455 		fixup_len = fixup_end - fixup_str;  in overlay_fixup_phandle()
457 		len -= fixup_len + 1;  in overlay_fixup_phandle()
463 			return -FDT_ERR_BADOVERLAY;  in overlay_fixup_phandle()
465 		path_len = sep - path;  in overlay_fixup_phandle()
466 		if (path_len == (fixup_len - 1))  in overlay_fixup_phandle()
467 			return -FDT_ERR_BADOVERLAY;  in overlay_fixup_phandle()
469 		fixup_len -= path_len + 1;  in overlay_fixup_phandle()
473 			return -FDT_ERR_BADOVERLAY;  in overlay_fixup_phandle()
475 		name_len = sep - name;  in overlay_fixup_phandle()
477 			return -FDT_ERR_BADOVERLAY;  in overlay_fixup_phandle()
481 			return -FDT_ERR_BADOVERLAY;  in overlay_fixup_phandle()
494  * overlay_fixup_phandles - Resolve the overlay phandles to the base
513 	int property;  in overlay_fixup_phandles()  local
517 	if (fixups_off == -FDT_ERR_NOTFOUND)  in overlay_fixup_phandles()
524 	if ((symbols_off < 0 && (symbols_off != -FDT_ERR_NOTFOUND)))  in overlay_fixup_phandles()
527 	fdt_for_each_property_offset(property, fdto, fixups_off) {  in overlay_fixup_phandles()
530 		ret = overlay_fixup_phandle(fdt, fdto, symbols_off, property);  in overlay_fixup_phandles()
539  * overlay_apply_node - Merges a node into the base device tree
541  * @target: Node offset in the base device tree to apply the fragment to
543  * @node: Node offset in the overlay holding the changes to merge
545  * overlay_apply_node() merges a node into a target base device tree
546  * node pointed.
558 			      void *fdto, int node)  in overlay_apply_node()  argument
560 	int property;  in overlay_apply_node()  local
563 	fdt_for_each_property_offset(property, fdto, node) {  in overlay_apply_node()
569 		prop = fdt_getprop_by_offset(fdto, property, &name,  in overlay_apply_node()
571 		if (prop_len == -FDT_ERR_NOTFOUND)  in overlay_apply_node()
572 			return -FDT_ERR_INTERNAL;  in overlay_apply_node()
581 	fdt_for_each_subnode(subnode, fdto, node) {  in overlay_apply_node()
587 		if (nnode == -FDT_ERR_EXISTS) {  in overlay_apply_node()
589 			if (nnode == -FDT_ERR_NOTFOUND)  in overlay_apply_node()
590 				return -FDT_ERR_INTERNAL;  in overlay_apply_node()
605  * overlay_merge - Merge an overlay into its base device tree
629 		 * Each fragments will have an __overlay__ node. If  in overlay_merge()
633 		if (overlay == -FDT_ERR_NOTFOUND)  in overlay_merge()
680  * overlay_symbol_update - Update the symbols of base tree after a merge
717 	if (root_sym == -FDT_ERR_NOTFOUND)  in overlay_symbol_update()
730 		/* verify it's a string property (terminated by a single \0) */  in overlay_symbol_update()
731 		if (path_len < 1 || memchr(path, '\0', path_len) != &path[path_len - 1])  in overlay_symbol_update()
732 			return -FDT_ERR_BADVALUE;  in overlay_symbol_update()
738 			return -FDT_ERR_BADVALUE;  in overlay_symbol_update()
749 		frag_name_len = s - path - 1;  in overlay_symbol_update()
752 		len = sizeof("/__overlay__/") - 1;  in overlay_symbol_update()
753 		if ((e - s) > len && (memcmp(s, "/__overlay__/", len) == 0)) {  in overlay_symbol_update()
754 			/* /<fragment-name>/__overlay__/<relative-subnode-path> */  in overlay_symbol_update()
756 			rel_path_len = e - rel_path - 1;  in overlay_symbol_update()
757 		} else if ((e - s) == len  in overlay_symbol_update()
758 			   && (memcmp(s, "/__overlay__", len - 1) == 0)) {  in overlay_symbol_update()
759 			/* /<fragment-name>/__overlay__ */  in overlay_symbol_update()
773 			return -FDT_ERR_BADOVERLAY;  in overlay_symbol_update()
779 			return -FDT_ERR_BADOVERLAY;  in overlay_symbol_update()
787 		/* if we have a target path use */  in overlay_symbol_update()
820 			len--;  in overlay_symbol_update()