| // SPDX-License-Identifier: GPL-2.0-or-later OR BSD-2-Clause |
| /* |
| * libfdt - Flat Device Tree manipulation |
| * Copyright (C) 2016 Free Electrons |
| * Copyright (C) 2016 NextThing Co. |
| */ |
| #include "libfdt_env.h" |
| |
| #include <fdt.h> |
| #include <libfdt.h> |
| |
| #include "libfdt_internal.h" |
| |
| /** |
| * overlay_get_target_phandle - retrieves the target phandle of a fragment |
| * @fdto: pointer to the device tree overlay blob |
| * @fragment: node offset of the fragment in the overlay |
| * |
| * overlay_get_target_phandle() retrieves the target phandle of an |
| * overlay fragment when that fragment uses a phandle (target |
| * property) instead of a path (target-path property). |
| * |
| * returns: |
| * the phandle pointed by the target property |
| * 0, if the phandle was not found |
| * -1, if the phandle was malformed |
| */ |
| static uint32_t overlay_get_target_phandle(const void *fdto, int fragment) |
| { |
| const fdt32_t *val; |
| int len; |
| |
| val = fdt_getprop(fdto, fragment, "target", &len); |
| if (!val) |
| return 0; |
| |
| if ((len != sizeof(*val)) || (fdt32_to_cpu(*val) == (uint32_t)-1)) |
| return (uint32_t)-1; |
| |
| return fdt32_to_cpu(*val); |
| } |
| |
| /** |
| * overlay_get_target - retrieves the offset of a fragment's target |
| * @fdt: Base device tree blob |
| * @fdto: Device tree overlay blob |
| * @fragment: node offset of the fragment in the overlay |
| * @pathp: pointer which receives the path of the target (or NULL) |
| * |
| * overlay_get_target() retrieves the target offset in the base |
| * device tree of a fragment, no matter how the actual targeting is |
| * done (through a phandle or a path) |
| * |
| * returns: |
| * the targeted node offset in the base device tree |
| * Negative error code on error |
| */ |
| static int overlay_get_target(const void *fdt, const void *fdto, |
| int fragment, char const **pathp) |
| { |
| uint32_t phandle; |
| const char *path = NULL; |
| int path_len = 0, ret; |
| |
| /* Try first to do a phandle based lookup */ |
| phandle = overlay_get_target_phandle(fdto, fragment); |
| if (phandle == (uint32_t)-1) |
| return -FDT_ERR_BADPHANDLE; |
| |
| /* no phandle, try path */ |
| if (!phandle) { |
| /* And then a path based lookup */ |
| path = fdt_getprop(fdto, fragment, "target-path", &path_len); |
| if (path) |
| ret = fdt_path_offset(fdt, path); |
| else |
| ret = path_len; |
| } else |
| ret = fdt_node_offset_by_phandle(fdt, phandle); |
| |
| /* |
| * If we haven't found either a target or a |
| * target-path property in a node that contains a |
| * __overlay__ subnode (we wouldn't be called |
| * otherwise), consider it a improperly written |
| * overlay |
| */ |
| if (ret < 0 && path_len == -FDT_ERR_NOTFOUND) |
| ret = -FDT_ERR_BADOVERLAY; |
| |
| /* return on error */ |
| if (ret < 0) |
| return ret; |
| |
| /* return pointer to path (if available) */ |
| if (pathp) |
| *pathp = path ? path : NULL; |
| |
| return ret; |
| } |
| |
| /** |
| * overlay_phandle_add_offset - Increases a phandle by an offset |
| * @fdt: Base device tree blob |
| * @node: Device tree overlay blob |
| * @name: Name of the property to modify (phandle or linux,phandle) |
| * @delta: offset to apply |
| * |
| * overlay_phandle_add_offset() increments a node phandle by a given |
| * offset. |
| * |
| * returns: |
| * 0 on success. |
| * Negative error code on error |
| */ |
| static int overlay_phandle_add_offset(void *fdt, int node, |
| const char *name, uint32_t delta) |
| { |
| const fdt32_t *val; |
| uint32_t adj_val; |
| int len; |
| |
| val = fdt_getprop(fdt, node, name, &len); |
| if (!val) |
| return len; |
| |
| if (len != sizeof(*val)) |
| return -FDT_ERR_BADPHANDLE; |
| |
| adj_val = fdt32_to_cpu(*val); |
| if ((adj_val + delta) < adj_val) |
| return -FDT_ERR_NOPHANDLES; |
| |
| adj_val += delta; |
| if (adj_val == (uint32_t)-1) |
| return -FDT_ERR_NOPHANDLES; |
| |
| return fdt_setprop_inplace_u32(fdt, node, name, adj_val); |
| } |
| |
| /** |
| * overlay_adjust_node_phandles - Offsets the phandles of a node |
| * @fdto: Device tree overlay blob |
| * @node: Offset of the node we want to adjust |
| * @delta: Offset to shift the phandles of |
| * |
| * overlay_adjust_node_phandles() adds a constant to all the phandles |
| * of a given node. This is mainly use as part of the overlay |
| * application process, when we want to update all the overlay |
| * phandles to not conflict with the overlays of the base device tree. |
| * |
| * returns: |
| * 0 on success |
| * Negative error code on failure |
| */ |
| static int overlay_adjust_node_phandles(void *fdto, int node, |
| uint32_t delta) |
| { |
| int child; |
| int ret; |
| |
| ret = overlay_phandle_add_offset(fdto, node, "phandle", delta); |
| if (ret && ret != -FDT_ERR_NOTFOUND) |
| return ret; |
| |
| ret = overlay_phandle_add_offset(fdto, node, "linux,phandle", delta); |
| if (ret && ret != -FDT_ERR_NOTFOUND) |
| return ret; |
| |
| fdt_for_each_subnode(child, fdto, node) { |
| ret = overlay_adjust_node_phandles(fdto, child, delta); |
| if (ret) |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * overlay_adjust_local_phandles - Adjust the phandles of a whole overlay |
| * @fdto: Device tree overlay blob |
| * @delta: Offset to shift the phandles of |
| * |
| * overlay_adjust_local_phandles() adds a constant to all the |
| * phandles of an overlay. This is mainly use as part of the overlay |
| * application process, when we want to update all the overlay |
| * phandles to not conflict with the overlays of the base device tree. |
| * |
| * returns: |
| * 0 on success |
| * Negative error code on failure |
| */ |
| static int overlay_adjust_local_phandles(void *fdto, uint32_t delta) |
| { |
| /* |
| * Start adjusting the phandles from the overlay root |
| */ |
| return overlay_adjust_node_phandles(fdto, 0, delta); |
| } |
| |
| /** |
| * overlay_update_local_node_references - Adjust the overlay references |
| * @fdto: Device tree overlay blob |
| * @tree_node: Node offset of the node to operate on |
| * @fixup_node: Node offset of the matching local fixups node |
| * @delta: Offset to shift the phandles of |
| * |
| * overlay_update_local_nodes_references() update the phandles |
| * pointing to a node within the device tree overlay by adding a |
| * constant delta. |
| * |
| * This is mainly used as part of a device tree application process, |
| * where you want the device tree overlays phandles to not conflict |
| * with the ones from the base device tree before merging them. |
| * |
| * returns: |
| * 0 on success |
| * Negative error code on failure |
| */ |
| static int overlay_update_local_node_references(void *fdto, |
| int tree_node, |
| int fixup_node, |
| uint32_t delta) |
| { |
| int fixup_prop; |
| int fixup_child; |
| int ret; |
| |
| fdt_for_each_property_offset(fixup_prop, fdto, fixup_node) { |
| const fdt32_t *fixup_val; |
| const char *tree_val; |
| const char *name; |
| int fixup_len; |
| int tree_len; |
| int i; |
| |
| fixup_val = fdt_getprop_by_offset(fdto, fixup_prop, |
| &name, &fixup_len); |
| if (!fixup_val) |
| return fixup_len; |
| |
| if (fixup_len % sizeof(uint32_t)) |
| return -FDT_ERR_BADOVERLAY; |
| fixup_len /= sizeof(uint32_t); |
| |
| tree_val = fdt_getprop(fdto, tree_node, name, &tree_len); |
| if (!tree_val) { |
| if (tree_len == -FDT_ERR_NOTFOUND) |
| return -FDT_ERR_BADOVERLAY; |
| |
| return tree_len; |
| } |
| |
| for (i = 0; i < fixup_len; i++) { |
| fdt32_t adj_val; |
| uint32_t poffset; |
| |
| poffset = fdt32_to_cpu(fixup_val[i]); |
| |
| /* |
| * phandles to fixup can be unaligned. |
| * |
| * Use a memcpy for the architectures that do |
| * not support unaligned accesses. |
| */ |
| memcpy(&adj_val, tree_val + poffset, sizeof(adj_val)); |
| |
| adj_val = cpu_to_fdt32(fdt32_to_cpu(adj_val) + delta); |
| |
| ret = fdt_setprop_inplace_namelen_partial(fdto, |
| tree_node, |
| name, |
| strlen(name), |
| poffset, |
| &adj_val, |
| sizeof(adj_val)); |
| if (ret == -FDT_ERR_NOSPACE) |
| return -FDT_ERR_BADOVERLAY; |
| |
| if (ret) |
| return ret; |
| } |
| } |
| |
| fdt_for_each_subnode(fixup_child, fdto, fixup_node) { |
| const char *fixup_child_name = fdt_get_name(fdto, fixup_child, |
| NULL); |
| int tree_child; |
| |
| tree_child = fdt_subnode_offset(fdto, tree_node, |
| fixup_child_name); |
| if (tree_child == -FDT_ERR_NOTFOUND) |
| return -FDT_ERR_BADOVERLAY; |
| if (tree_child < 0) |
| return tree_child; |
| |
| ret = overlay_update_local_node_references(fdto, |
| tree_child, |
| fixup_child, |
| delta); |
| if (ret) |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * overlay_update_local_references - Adjust the overlay references |
| * @fdto: Device tree overlay blob |
| * @delta: Offset to shift the phandles of |
| * |
| * overlay_update_local_references() update all the phandles pointing |
| * to a node within the device tree overlay by adding a constant |
| * delta to not conflict with the base overlay. |
| * |
| * This is mainly used as part of a device tree application process, |
| * where you want the device tree overlays phandles to not conflict |
| * with the ones from the base device tree before merging them. |
| * |
| * returns: |
| * 0 on success |
| * Negative error code on failure |
| */ |
| static int overlay_update_local_references(void *fdto, uint32_t delta) |
| { |
| int fixups; |
| |
| fixups = fdt_path_offset(fdto, "/__local_fixups__"); |
| if (fixups < 0) { |
| /* There's no local phandles to adjust, bail out */ |
| if (fixups == -FDT_ERR_NOTFOUND) |
| return 0; |
| |
| return fixups; |
| } |
| |
| /* |
| * Update our local references from the root of the tree |
| */ |
| return overlay_update_local_node_references(fdto, 0, fixups, |
| delta); |
| } |
| |
| /** |
| * overlay_fixup_one_phandle - Set an overlay phandle to the base one |
| * @fdt: Base Device Tree blob |
| * @fdto: Device tree overlay blob |
| * @symbols_off: Node offset of the symbols node in the base device tree |
| * @path: Path to a node holding a phandle in the overlay |
| * @path_len: number of path characters to consider |
| * @name: Name of the property holding the phandle reference in the overlay |
| * @name_len: number of name characters to consider |
| * @poffset: Offset within the overlay property where the phandle is stored |
| * @label: Label of the node referenced by the phandle |
| * |
| * overlay_fixup_one_phandle() resolves an overlay phandle pointing to |
| * a node in the base device tree. |
| * |
| * This is part of the device tree overlay application process, when |
| * you want all the phandles in the overlay to point to the actual |
| * base dt nodes. |
| * |
| * returns: |
| * 0 on success |
| * Negative error code on failure |
| */ |
| static int overlay_fixup_one_phandle(void *fdt, void *fdto, |
| int symbols_off, |
| const char *path, uint32_t path_len, |
| const char *name, uint32_t name_len, |
| int poffset, const char *label) |
| { |
| const char *symbol_path; |
| uint32_t phandle; |
| fdt32_t phandle_prop; |
| int symbol_off, fixup_off; |
| int prop_len; |
| |
| if (symbols_off < 0) |
| return symbols_off; |
| |
| symbol_path = fdt_getprop(fdt, symbols_off, label, |
| &prop_len); |
| if (!symbol_path) |
| return prop_len; |
| |
| symbol_off = fdt_path_offset(fdt, symbol_path); |
| if (symbol_off < 0) |
| return symbol_off; |
| |
| phandle = fdt_get_phandle(fdt, symbol_off); |
| if (!phandle) |
| return -FDT_ERR_NOTFOUND; |
| |
| fixup_off = fdt_path_offset_namelen(fdto, path, path_len); |
| if (fixup_off == -FDT_ERR_NOTFOUND) |
| return -FDT_ERR_BADOVERLAY; |
| if (fixup_off < 0) |
| return fixup_off; |
| |
| phandle_prop = cpu_to_fdt32(phandle); |
| return fdt_setprop_inplace_namelen_partial(fdto, fixup_off, |
| name, name_len, poffset, |
| &phandle_prop, |
| sizeof(phandle_prop)); |
| } |
| |
| /** |
| * overlay_fixup_phandle - Set an overlay phandle to the base one |
| * @fdt: Base Device Tree blob |
| * @fdto: Device tree overlay blob |
| * @symbols_off: Node offset of the symbols node in the base device tree |
| * @property: Property offset in the overlay holding the list of fixups |
| * |
| * overlay_fixup_phandle() resolves all the overlay phandles pointed |
| * to in a __fixups__ property, and updates them to match the phandles |
| * in use in the base device tree. |
| * |
| * This is part of the device tree overlay application process, when |
| * you want all the phandles in the overlay to point to the actual |
| * base dt nodes. |
| * |
| * returns: |
| * 0 on success |
| * Negative error code on failure |
| */ |
| static int overlay_fixup_phandle(void *fdt, void *fdto, int symbols_off, |
| int property) |
| { |
| const char *value; |
| const char *label; |
| int len; |
| |
| value = fdt_getprop_by_offset(fdto, property, |
| &label, &len); |
| if (!value) { |
| if (len == -FDT_ERR_NOTFOUND) |
| return -FDT_ERR_INTERNAL; |
| |
| return len; |
| } |
| |
| do { |
| const char *path, *name, *fixup_end; |
| const char *fixup_str = value; |
| uint32_t path_len, name_len; |
| uint32_t fixup_len; |
| char *sep, *endptr; |
| int poffset, ret; |
| |
| fixup_end = memchr(value, '\0', len); |
| if (!fixup_end) |
| return -FDT_ERR_BADOVERLAY; |
| fixup_len = fixup_end - fixup_str; |
| |
| len -= fixup_len + 1; |
| value += fixup_len + 1; |
| |
| path = fixup_str; |
| sep = memchr(fixup_str, ':', fixup_len); |
| if (!sep || *sep != ':') |
| return -FDT_ERR_BADOVERLAY; |
| |
| path_len = sep - path; |
| if (path_len == (fixup_len - 1)) |
| return -FDT_ERR_BADOVERLAY; |
| |
| fixup_len -= path_len + 1; |
| name = sep + 1; |
| sep = memchr(name, ':', fixup_len); |
| if (!sep || *sep != ':') |
| return -FDT_ERR_BADOVERLAY; |
| |
| name_len = sep - name; |
| if (!name_len) |
| return -FDT_ERR_BADOVERLAY; |
| |
| poffset = strtoul(sep + 1, &endptr, 10); |
| if ((*endptr != '\0') || (endptr <= (sep + 1))) |
| return -FDT_ERR_BADOVERLAY; |
| |
| ret = overlay_fixup_one_phandle(fdt, fdto, symbols_off, |
| path, path_len, name, name_len, |
| poffset, label); |
| if (ret) |
| return ret; |
| } while (len > 0); |
| |
| return 0; |
| } |
| |
| /** |
| * overlay_fixup_phandles - Resolve the overlay phandles to the base |
| * device tree |
| * @fdt: Base Device Tree blob |
| * @fdto: Device tree overlay blob |
| * |
| * overlay_fixup_phandles() resolves all the overlay phandles pointing |
| * to nodes in the base device tree. |
| * |
| * This is one of the steps of the device tree overlay application |
| * process, when you want all the phandles in the overlay to point to |
| * the actual base dt nodes. |
| * |
| * returns: |
| * 0 on success |
| * Negative error code on failure |
| */ |
| static int overlay_fixup_phandles(void *fdt, void *fdto) |
| { |
| int fixups_off, symbols_off; |
| int property; |
| |
| /* We can have overlays without any fixups */ |
| fixups_off = fdt_path_offset(fdto, "/__fixups__"); |
| if (fixups_off == -FDT_ERR_NOTFOUND) |
| return 0; /* nothing to do */ |
| if (fixups_off < 0) |
| return fixups_off; |
| |
| /* And base DTs without symbols */ |
| symbols_off = fdt_path_offset(fdt, "/__symbols__"); |
| if ((symbols_off < 0 && (symbols_off != -FDT_ERR_NOTFOUND))) |
| return symbols_off; |
| |
| fdt_for_each_property_offset(property, fdto, fixups_off) { |
| int ret; |
| |
| ret = overlay_fixup_phandle(fdt, fdto, symbols_off, property); |
| if (ret) |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * overlay_apply_node - Merges a node into the base device tree |
| * @fdt: Base Device Tree blob |
| * @target: Node offset in the base device tree to apply the fragment to |
| * @fdto: Device tree overlay blob |
| * @node: Node offset in the overlay holding the changes to merge |
| * |
| * overlay_apply_node() merges a node into a target base device tree |
| * node pointed. |
| * |
| * This is part of the final step in the device tree overlay |
| * application process, when all the phandles have been adjusted and |
| * resolved and you just have to merge overlay into the base device |
| * tree. |
| * |
| * returns: |
| * 0 on success |
| * Negative error code on failure |
| */ |
| static int overlay_apply_node(void *fdt, int target, |
| void *fdto, int node) |
| { |
| int property; |
| int subnode; |
| |
| fdt_for_each_property_offset(property, fdto, node) { |
| const char *name; |
| const void *prop; |
| int prop_len; |
| int ret; |
| |
| prop = fdt_getprop_by_offset(fdto, property, &name, |
| &prop_len); |
| if (prop_len == -FDT_ERR_NOTFOUND) |
| return -FDT_ERR_INTERNAL; |
| if (prop_len < 0) |
| return prop_len; |
| |
| ret = fdt_setprop(fdt, target, name, prop, prop_len); |
| if (ret) |
| return ret; |
| } |
| |
| fdt_for_each_subnode(subnode, fdto, node) { |
| const char *name = fdt_get_name(fdto, subnode, NULL); |
| int nnode; |
| int ret; |
| |
| nnode = fdt_add_subnode(fdt, target, name); |
| if (nnode == -FDT_ERR_EXISTS) { |
| nnode = fdt_subnode_offset(fdt, target, name); |
| if (nnode == -FDT_ERR_NOTFOUND) |
| return -FDT_ERR_INTERNAL; |
| } |
| |
| if (nnode < 0) |
| return nnode; |
| |
| ret = overlay_apply_node(fdt, nnode, fdto, subnode); |
| if (ret) |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * overlay_merge - Merge an overlay into its base device tree |
| * @fdt: Base Device Tree blob |
| * @fdto: Device tree overlay blob |
| * |
| * overlay_merge() merges an overlay into its base device tree. |
| * |
| * This is the next to last step in the device tree overlay application |
| * process, when all the phandles have been adjusted and resolved and |
| * you just have to merge overlay into the base device tree. |
| * |
| * returns: |
| * 0 on success |
| * Negative error code on failure |
| */ |
| static int overlay_merge(void *fdt, void *fdto) |
| { |
| int fragment; |
| |
| fdt_for_each_subnode(fragment, fdto, 0) { |
| int overlay; |
| int target; |
| int ret; |
| |
| /* |
| * Each fragments will have an __overlay__ node. If |
| * they don't, it's not supposed to be merged |
| */ |
| overlay = fdt_subnode_offset(fdto, fragment, "__overlay__"); |
| if (overlay == -FDT_ERR_NOTFOUND) |
| continue; |
| |
| if (overlay < 0) |
| return overlay; |
| |
| target = overlay_get_target(fdt, fdto, fragment, NULL); |
| if (target < 0) |
| return target; |
| |
| ret = overlay_apply_node(fdt, target, fdto, overlay); |
| if (ret) |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static int get_path_len(const void *fdt, int nodeoffset) |
| { |
| int len = 0, namelen; |
| const char *name; |
| |
| FDT_RO_PROBE(fdt); |
| |
| for (;;) { |
| name = fdt_get_name(fdt, nodeoffset, &namelen); |
| if (!name) |
| return namelen; |
| |
| /* root? we're done */ |
| if (namelen == 0) |
| break; |
| |
| nodeoffset = fdt_parent_offset(fdt, nodeoffset); |
| if (nodeoffset < 0) |
| return nodeoffset; |
| len += namelen + 1; |
| } |
| |
| /* in case of root pretend it's "/" */ |
| if (len == 0) |
| len++; |
| return len; |
| } |
| |
| /** |
| * overlay_symbol_update - Update the symbols of base tree after a merge |
| * @fdt: Base Device Tree blob |
| * @fdto: Device tree overlay blob |
| * |
| * overlay_symbol_update() updates the symbols of the base tree with the |
| * symbols of the applied overlay |
| * |
| * This is the last step in the device tree overlay application |
| * process, allowing the reference of overlay symbols by subsequent |
| * overlay operations. |
| * |
| * returns: |
| * 0 on success |
| * Negative error code on failure |
| */ |
| static int overlay_symbol_update(void *fdt, void *fdto) |
| { |
| int root_sym, ov_sym, prop, path_len, fragment, target; |
| int len, frag_name_len, ret, rel_path_len; |
| const char *s, *e; |
| const char *path; |
| const char *name; |
| const char *frag_name; |
| const char *rel_path; |
| const char *target_path; |
| char *buf; |
| void *p; |
| |
| ov_sym = fdt_subnode_offset(fdto, 0, "__symbols__"); |
| |
| /* if no overlay symbols exist no problem */ |
| if (ov_sym < 0) |
| return 0; |
| |
| root_sym = fdt_subnode_offset(fdt, 0, "__symbols__"); |
| |
| /* it no root symbols exist we should create them */ |
| if (root_sym == -FDT_ERR_NOTFOUND) |
| root_sym = fdt_add_subnode(fdt, 0, "__symbols__"); |
| |
| /* any error is fatal now */ |
| if (root_sym < 0) |
| return root_sym; |
| |
| /* iterate over each overlay symbol */ |
| fdt_for_each_property_offset(prop, fdto, ov_sym) { |
| path = fdt_getprop_by_offset(fdto, prop, &name, &path_len); |
| if (!path) |
| return path_len; |
| |
| /* verify it's a string property (terminated by a single \0) */ |
| if (path_len < 1 || memchr(path, '\0', path_len) != &path[path_len - 1]) |
| return -FDT_ERR_BADVALUE; |
| |
| /* keep end marker to avoid strlen() */ |
| e = path + path_len; |
| |
| if (*path != '/') |
| return -FDT_ERR_BADVALUE; |
| |
| /* get fragment name first */ |
| s = strchr(path + 1, '/'); |
| if (!s) { |
| /* Symbol refers to something that won't end |
| * up in the target tree */ |
| continue; |
| } |
| |
| frag_name = path + 1; |
| frag_name_len = s - path - 1; |
| |
| /* verify format; safe since "s" lies in \0 terminated prop */ |
| len = sizeof("/__overlay__/") - 1; |
| if ((e - s) > len && (memcmp(s, "/__overlay__/", len) == 0)) { |
| /* /<fragment-name>/__overlay__/<relative-subnode-path> */ |
| rel_path = s + len; |
| rel_path_len = e - rel_path - 1; |
| } else if ((e - s) == len |
| && (memcmp(s, "/__overlay__", len - 1) == 0)) { |
| /* /<fragment-name>/__overlay__ */ |
| rel_path = ""; |
| rel_path_len = 0; |
| } else { |
| /* Symbol refers to something that won't end |
| * up in the target tree */ |
| continue; |
| } |
| |
| /* find the fragment index in which the symbol lies */ |
| ret = fdt_subnode_offset_namelen(fdto, 0, frag_name, |
| frag_name_len); |
| /* not found? */ |
| if (ret < 0) |
| return -FDT_ERR_BADOVERLAY; |
| fragment = ret; |
| |
| /* an __overlay__ subnode must exist */ |
| ret = fdt_subnode_offset(fdto, fragment, "__overlay__"); |
| if (ret < 0) |
| return -FDT_ERR_BADOVERLAY; |
| |
| /* get the target of the fragment */ |
| ret = overlay_get_target(fdt, fdto, fragment, &target_path); |
| if (ret < 0) |
| return ret; |
| target = ret; |
| |
| /* if we have a target path use */ |
| if (!target_path) { |
| ret = get_path_len(fdt, target); |
| if (ret < 0) |
| return ret; |
| len = ret; |
| } else { |
| len = strlen(target_path); |
| } |
| |
| ret = fdt_setprop_placeholder(fdt, root_sym, name, |
| len + (len > 1) + rel_path_len + 1, &p); |
| if (ret < 0) |
| return ret; |
| |
| if (!target_path) { |
| /* again in case setprop_placeholder changed it */ |
| ret = overlay_get_target(fdt, fdto, fragment, &target_path); |
| if (ret < 0) |
| return ret; |
| target = ret; |
| } |
| |
| buf = p; |
| if (len > 1) { /* target is not root */ |
| if (!target_path) { |
| ret = fdt_get_path(fdt, target, buf, len + 1); |
| if (ret < 0) |
| return ret; |
| } else |
| memcpy(buf, target_path, len + 1); |
| |
| } else |
| len--; |
| |
| buf[len] = '/'; |
| memcpy(buf + len + 1, rel_path, rel_path_len); |
| buf[len + 1 + rel_path_len] = '\0'; |
| } |
| |
| return 0; |
| } |
| |
| int fdt_overlay_apply(void *fdt, void *fdto) |
| { |
| uint32_t delta; |
| int ret; |
| |
| FDT_RO_PROBE(fdt); |
| FDT_RO_PROBE(fdto); |
| |
| ret = fdt_find_max_phandle(fdt, &delta); |
| if (ret) |
| goto err; |
| |
| ret = overlay_adjust_local_phandles(fdto, delta); |
| if (ret) |
| goto err; |
| |
| ret = overlay_update_local_references(fdto, delta); |
| if (ret) |
| goto err; |
| |
| ret = overlay_fixup_phandles(fdt, fdto); |
| if (ret) |
| goto err; |
| |
| ret = overlay_merge(fdt, fdto); |
| if (ret) |
| goto err; |
| |
| ret = overlay_symbol_update(fdt, fdto); |
| if (ret) |
| goto err; |
| |
| /* |
| * The overlay has been damaged, erase its magic. |
| */ |
| fdt_set_magic(fdto, ~0); |
| |
| return 0; |
| |
| err: |
| /* |
| * The overlay might have been damaged, erase its magic. |
| */ |
| fdt_set_magic(fdto, ~0); |
| |
| /* |
| * The base device tree might have been damaged, erase its |
| * magic. |
| */ |
| fdt_set_magic(fdt, ~0); |
| |
| return ret; |
| } |