// SPDX-License-Identifier: GPL-2.0+ /* * Originally from Linux v4.9 * Paul Mackerras August 1996. * Copyright (C) 1996-2005 Paul Mackerras. * * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner. * {engebret|bergner}@us.ibm.com * * Adapted for sparc and sparc64 by David S. Miller davem@davemloft.net * * Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell and * Grant Likely. * * Modified for U-Boot * Copyright (c) 2017 Google, Inc * * This file follows drivers/of/base.c with functions in the same order as the * Linux version. */ #include #include #include #include #include #include #include #include #include #include DECLARE_GLOBAL_DATA_PTR; /* list of struct alias_prop aliases */ static LIST_HEAD(aliases_lookup); /* "/aliaes" node */ static struct device_node *of_aliases; /* "/chosen" node */ static struct device_node *of_chosen; /* node pointed to by the stdout-path alias */ static struct device_node *of_stdout; /* pointer to options given after the alias (separated by :) or NULL if none */ static const char *of_stdout_options; /** * struct alias_prop - Alias property in 'aliases' node * * The structure represents one alias property of 'aliases' node as * an entry in aliases_lookup list. * * @link: List node to link the structure in aliases_lookup list * @alias: Alias property name * @np: Pointer to device_node that the alias stands for * @id: Index value from end of alias name * @stem: Alias string without the index */ struct alias_prop { struct list_head link; const char *alias; struct device_node *np; int id; char stem[0]; }; int of_n_addr_cells(const struct device_node *np) { const __be32 *ip; do { if (np->parent) np = np->parent; ip = of_get_property(np, "#address-cells", NULL); if (ip) return be32_to_cpup(ip); } while (np->parent); /* No #address-cells property for the root node */ return OF_ROOT_NODE_ADDR_CELLS_DEFAULT; } int of_n_size_cells(const struct device_node *np) { const __be32 *ip; do { if (np->parent) np = np->parent; ip = of_get_property(np, "#size-cells", NULL); if (ip) return be32_to_cpup(ip); } while (np->parent); /* No #size-cells property for the root node */ return OF_ROOT_NODE_SIZE_CELLS_DEFAULT; } int of_simple_addr_cells(const struct device_node *np) { const __be32 *ip; ip = of_get_property(np, "#address-cells", NULL); if (ip) return be32_to_cpup(ip); /* Return a default of 2 to match fdt_address_cells()*/ return 2; } int of_simple_size_cells(const struct device_node *np) { const __be32 *ip; ip = of_get_property(np, "#size-cells", NULL); if (ip) return be32_to_cpup(ip); /* Return a default of 2 to match fdt_size_cells()*/ return 2; } struct property *of_find_property(const struct device_node *np, const char *name, int *lenp) { struct property *pp; if (!np) return NULL; for (pp = np->properties; pp; pp = pp->next) { if (strcmp(pp->name, name) == 0) { if (lenp) *lenp = pp->length; break; } } if (!pp && lenp) *lenp = -FDT_ERR_NOTFOUND; return pp; } struct device_node *of_find_all_nodes(struct device_node *prev) { struct device_node *np; if (!prev) { np = gd->of_root; } else if (prev->child) { np = prev->child; } else { /* * Walk back up looking for a sibling, or the end of the * structure */ np = prev; while (np->parent && !np->sibling) np = np->parent; np = np->sibling; /* Might be null at the end of the tree */ } return np; } const void *of_get_property(const struct device_node *np, const char *name, int *lenp) { struct property *pp = of_find_property(np, name, lenp); return pp ? pp->value : NULL; } const struct property *of_get_first_property(const struct device_node *np) { if (!np) return NULL; return np->properties; } const struct property *of_get_next_property(const struct device_node *np, const struct property *property) { if (!np) return NULL; return property->next; } const void *of_get_property_by_prop(const struct device_node *np, const struct property *property, const char **name, int *lenp) { if (!np || !property) return NULL; if (name) *name = property->name; if (lenp) *lenp = property->length; return property->value; } static const char *of_prop_next_string(struct property *prop, const char *cur) { const void *curv = cur; if (!prop) return NULL; if (!cur) return prop->value; curv += strlen(cur) + 1; if (curv >= prop->value + prop->length) return NULL; return curv; } int of_device_is_compatible(const struct device_node *device, const char *compat, const char *type, const char *name) { struct property *prop; const char *cp; int index = 0, score = 0; /* Compatible match has highest priority */ if (compat && compat[0]) { prop = of_find_property(device, "compatible", NULL); for (cp = of_prop_next_string(prop, NULL); cp; cp = of_prop_next_string(prop, cp), index++) { if (of_compat_cmp(cp, compat, strlen(compat)) == 0) { score = INT_MAX/2 - (index << 2); break; } } if (!score) return 0; } /* Matching type is better than matching name */ if (type && type[0]) { if (!device->type || of_node_cmp(type, device->type)) return 0; score += 2; } /* Matching name is a bit better than not */ if (name && name[0]) { if (!device->name || of_node_cmp(name, device->name)) return 0; score++; } return score; } bool of_device_is_available(const struct device_node *device) { const char *status; int statlen; if (!device) return false; status = of_get_property(device, "status", &statlen); if (status == NULL) return true; if (statlen > 0) { if (!strcmp(status, "okay")) return true; } return false; } struct device_node *of_get_parent(const struct device_node *node) { const struct device_node *np; if (!node) return NULL; np = of_node_get(node->parent); return (struct device_node *)np; } static struct device_node *__of_get_next_child(const struct device_node *node, struct device_node *prev) { struct device_node *next; if (!node) return NULL; next = prev ? prev->sibling : node->child; /* * coverity[dead_error_line : FALSE] * Dead code here since our current implementation of of_node_get() * always returns NULL (Coverity CID 163245). But we leave it as is * since we may want to implement get/put later. */ for (; next; next = next->sibling) if (of_node_get(next)) break; of_node_put(prev); return next; } #define __for_each_child_of_node(parent, child) \ for (child = __of_get_next_child(parent, NULL); child != NULL; \ child = __of_get_next_child(parent, child)) static struct device_node *__of_find_node_by_path(struct device_node *parent, const char *path) { struct device_node *child; int len; len = strcspn(path, "/:"); if (!len) return NULL; __for_each_child_of_node(parent, child) { const char *name = strrchr(child->full_name, '/'); name++; if (strncmp(path, name, len) == 0 && (strlen(name) == len)) return child; } return NULL; } #define for_each_property_of_node(dn, pp) \ for (pp = dn->properties; pp != NULL; pp = pp->next) struct device_node *of_find_node_opts_by_path(struct device_node *root, const char *path, const char **opts) { struct device_node *np = NULL; struct property *pp; const char *separator = strchr(path, ':'); if (!root) root = gd->of_root; if (opts) *opts = separator ? separator + 1 : NULL; if (strcmp(path, "/") == 0) return of_node_get(root); /* The path could begin with an alias */ if (*path != '/') { int len; const char *p = separator; /* Only allow alias processing on the control FDT */ if (root != gd->of_root) return NULL; if (!p) p = strchrnul(path, '/'); len = p - path; /* of_aliases must not be NULL */ if (!of_aliases) return NULL; for_each_property_of_node(of_aliases, pp) { if (strlen(pp->name) == len && !strncmp(pp->name, path, len)) { np = of_find_node_by_path(pp->value); break; } } if (!np) return NULL; path = p; } /* Step down the tree matching path components */ if (!np) np = of_node_get(root); while (np && *path == '/') { struct device_node *tmp = np; path++; /* Increment past '/' delimiter */ np = __of_find_node_by_path(np, path); of_node_put(tmp); path = strchrnul(path, '/'); if (separator && separator < path) break; } return np; } struct device_node *of_find_compatible_node(struct device_node *from, const char *type, const char *compatible) { struct device_node *np; for_each_of_allnodes_from(from, np) if (of_device_is_compatible(np, compatible, type, NULL) && of_node_get(np)) break; of_node_put(from); return np; } static int of_device_has_prop_value(const struct device_node *device, const char *propname, const void *propval, int proplen) { struct property *prop = of_find_property(device, propname, NULL); if (!prop || !prop->value || prop->length != proplen) return 0; return !memcmp(prop->value, propval, proplen); } struct device_node *of_find_node_by_prop_value(struct device_node *from, const char *propname, const void *propval, int proplen) { struct device_node *np; for_each_of_allnodes_from(from, np) { if (of_device_has_prop_value(np, propname, propval, proplen) && of_node_get(np)) break; } of_node_put(from); return np; } struct device_node *of_find_node_by_phandle(struct device_node *root, phandle handle) { struct device_node *np; if (!handle) return NULL; for_each_of_allnodes_from(root, np) if (np->phandle == handle) break; (void)of_node_get(np); return np; } /** * of_find_property_value_of_size() - find property of given size * * Search for a property in a device node and validate the requested size. * * @np: device node from which the property value is to be read. * @propname: name of the property to be searched. * @len: requested length of property value * * Return: the property value on success, -EINVAL if the property does not * exist and -EOVERFLOW if the property data isn't large enough. */ static void *of_find_property_value_of_size(const struct device_node *np, const char *propname, u32 len) { struct property *prop = of_find_property(np, propname, NULL); if (!prop) return ERR_PTR(-EINVAL); if (len > prop->length) return ERR_PTR(-EOVERFLOW); return prop->value; } int of_read_u8(const struct device_node *np, const char *propname, u8 *outp) { const u8 *val; debug("%s: %s: ", __func__, propname); if (!np) return -EINVAL; val = of_find_property_value_of_size(np, propname, sizeof(*outp)); if (IS_ERR(val)) { debug("(not found)\n"); return PTR_ERR(val); } *outp = *val; debug("%#x (%d)\n", *outp, *outp); return 0; } int of_read_u16(const struct device_node *np, const char *propname, u16 *outp) { const __be16 *val; debug("%s: %s: ", __func__, propname); if (!np) return -EINVAL; val = of_find_property_value_of_size(np, propname, sizeof(*outp)); if (IS_ERR(val)) { debug("(not found)\n"); return PTR_ERR(val); } *outp = be16_to_cpup(val); debug("%#x (%d)\n", *outp, *outp); return 0; } int of_read_u32(const struct device_node *np, const char *propname, u32 *outp) { return of_read_u32_index(np, propname, 0, outp); } int of_read_u32_array(const struct device_node *np, const char *propname, u32 *out_values, size_t sz) { const __be32 *val; debug("%s: %s: ", __func__, propname); val = of_find_property_value_of_size(np, propname, sz * sizeof(*out_values)); if (IS_ERR(val)) return PTR_ERR(val); debug("size %zd\n", sz); while (sz--) *out_values++ = be32_to_cpup(val++); return 0; } int of_read_u32_index(const struct device_node *np, const char *propname, int index, u32 *outp) { const __be32 *val; debug("%s: %s: ", __func__, propname); if (!np) return -EINVAL; val = of_find_property_value_of_size(np, propname, sizeof(*outp) * (index + 1)); if (IS_ERR(val)) { debug("(not found)\n"); return PTR_ERR(val); } *outp = be32_to_cpup(val + index); debug("%#x (%d)\n", *outp, *outp); return 0; } int of_read_u64_index(const struct device_node *np, const char *propname, int index, u64 *outp) { const __be64 *val; debug("%s: %s: ", __func__, propname); if (!np) return -EINVAL; val = of_find_property_value_of_size(np, propname, sizeof(*outp) * (index + 1)); if (IS_ERR(val)) { debug("(not found)\n"); return PTR_ERR(val); } *outp = be64_to_cpup(val + index); debug("%#llx (%lld)\n", (unsigned long long)*outp, (unsigned long long)*outp); return 0; } int of_read_u64(const struct device_node *np, const char *propname, u64 *outp) { return of_read_u64_index(np, propname, 0, outp); } int of_property_match_string(const struct device_node *np, const char *propname, const char *string) { int len = 0; const struct property *prop = of_find_property(np, propname, &len); size_t l; int i; const char *p, *end; if (!prop && len == -FDT_ERR_NOTFOUND) return -ENOENT; if (!prop) return -EINVAL; if (!prop->value) return -ENODATA; p = prop->value; end = p + prop->length; for (i = 0; p < end; i++, p += l) { l = strnlen(p, end - p) + 1; if (p + l > end) return -EILSEQ; debug("comparing %s with %s\n", string, p); if (strcmp(string, p) == 0) return i; /* Found it; return index */ } return -ENODATA; } /** * of_property_read_string_helper() - Utility helper for parsing string properties * @np: device node from which the property value is to be read. * @propname: name of the property to be searched. * @out_strs: output array of string pointers. * @sz: number of array elements to read. * @skip: Number of strings to skip over at beginning of list (cannot be * negative) * * Don't call this function directly. It is a utility helper for the * of_property_read_string*() family of functions. */ int of_property_read_string_helper(const struct device_node *np, const char *propname, const char **out_strs, size_t sz, int skip) { const struct property *prop = of_find_property(np, propname, NULL); int l = 0, i = 0; const char *p, *end; if (!prop) return -EINVAL; if (!prop->value) return -ENODATA; p = prop->value; end = p + prop->length; for (i = 0; p < end && (!out_strs || i < skip + sz); i++, p += l) { l = strnlen(p, end - p) + 1; if (p + l > end) return -EILSEQ; if (out_strs && i >= skip) *out_strs++ = p; } i -= skip; return i <= 0 ? -ENODATA : i; } static int __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) { const __be32 *list, *list_end; int rc = 0, cur_index = 0; uint32_t count; struct device_node *node = NULL; phandle phandle; int size; /* Retrieve the phandle list property */ list = of_get_property(np, list_name, &size); if (!list) return -ENOENT; list_end = list + size / sizeof(*list); /* Loop over the phandles until all the requested entry is found */ while (list < list_end) { rc = -EINVAL; count = 0; /* * If phandle is 0, then it is an empty entry with no * arguments. Skip forward to the next entry. */ phandle = be32_to_cpup(list++); if (phandle) { /* * Find the provider node and parse the #*-cells * property to determine the argument length. * * This is not needed if the cell count is hard-coded * (i.e. cells_name not set, but cell_count is set), * except when we're going to return the found node * below. */ if (cells_name || cur_index == index) { node = of_find_node_by_phandle(NULL, phandle); if (!node) { debug("%s: could not find phandle\n", np->full_name); goto err; } } if (cells_name) { if (of_read_u32(node, cells_name, &count)) { debug("%s: could not get %s for %s\n", np->full_name, cells_name, node->full_name); goto err; } } else { count = cell_count; } /* * Make sure that the arguments actually fit in the * remaining property data length */ if (list + count > list_end) { debug("%s: arguments longer than property\n", np->full_name); goto err; } } /* * All of the error cases above bail out of the loop, so at * this point, the parsing is successful. If the requested * index matches, then fill the out_args structure and return, * or return -ENOENT for an empty entry. */ rc = -ENOENT; if (cur_index == index) { if (!phandle) goto err; if (out_args) { int i; if (WARN_ON(count > OF_MAX_PHANDLE_ARGS)) count = OF_MAX_PHANDLE_ARGS; out_args->np = node; out_args->args_count = count; for (i = 0; i < count; i++) out_args->args[i] = be32_to_cpup(list++); } else { of_node_put(node); } /* Found it! return success */ return 0; } of_node_put(node); node = NULL; list += count; cur_index++; } /* * Unlock node before returning result; will be one of: * -ENOENT : index is for empty phandle * -EINVAL : parsing error on data * [1..n] : Number of phandle (count mode; when index = -1) */ rc = index < 0 ? cur_index : -ENOENT; err: if (node) of_node_put(node); return rc; } struct device_node *of_parse_phandle(const struct device_node *np, const char *phandle_name, int index) { struct of_phandle_args args; if (index < 0) return NULL; if (__of_parse_phandle_with_args(np, phandle_name, NULL, 0, index, &args)) return NULL; return args.np; } int 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) { if (index < 0) return -EINVAL; return __of_parse_phandle_with_args(np, list_name, cells_name, cell_count, index, out_args); } int of_count_phandle_with_args(const struct device_node *np, const char *list_name, const char *cells_name, int cell_count) { return __of_parse_phandle_with_args(np, list_name, cells_name, cell_count, -1, NULL); } static void of_alias_add(struct alias_prop *ap, struct device_node *np, int id, const char *stem, int stem_len) { ap->np = np; ap->id = id; strncpy(ap->stem, stem, stem_len); ap->stem[stem_len] = 0; list_add_tail(&ap->link, &aliases_lookup); debug("adding DT alias:%s: stem=%s id=%i node=%s\n", ap->alias, ap->stem, ap->id, of_node_full_name(np)); } int of_alias_scan(void) { struct property *pp; of_aliases = of_find_node_by_path("/aliases"); of_chosen = of_find_node_by_path("/chosen"); if (of_chosen == NULL) of_chosen = of_find_node_by_path("/chosen@0"); if (of_chosen) { const char *name; name = of_get_property(of_chosen, "stdout-path", NULL); if (name) of_stdout = of_find_node_opts_by_path(NULL, name, &of_stdout_options); } if (!of_aliases) return 0; for_each_property_of_node(of_aliases, pp) { const char *start = pp->name; const char *end = start + strlen(start); struct device_node *np; struct alias_prop *ap; ulong id; int len; /* Skip those we do not want to proceed */ if (!strcmp(pp->name, "name") || !strcmp(pp->name, "phandle") || !strcmp(pp->name, "linux,phandle")) continue; np = of_find_node_by_path(pp->value); if (!np) continue; /* * walk the alias backwards to extract the id and work out * the 'stem' string */ while (isdigit(*(end-1)) && end > start) end--; len = end - start; if (strict_strtoul(end, 10, &id) < 0) continue; /* Allocate an alias_prop with enough space for the stem */ ap = malloc(sizeof(*ap) + len + 1); if (!ap) return -ENOMEM; memset(ap, 0, sizeof(*ap) + len + 1); ap->alias = start; of_alias_add(ap, np, id, start, len); } return 0; } int of_alias_get_id(const struct device_node *np, const char *stem) { struct alias_prop *app; int id = -ENODEV; mutex_lock(&of_mutex); list_for_each_entry(app, &aliases_lookup, link) { if (strcmp(app->stem, stem) != 0) continue; if (np == app->np) { id = app->id; break; } } mutex_unlock(&of_mutex); return id; } int of_alias_get_highest_id(const char *stem) { struct alias_prop *app; int id = -1; mutex_lock(&of_mutex); list_for_each_entry(app, &aliases_lookup, link) { if (strcmp(app->stem, stem) != 0) continue; if (app->id > id) id = app->id; } mutex_unlock(&of_mutex); return id; } struct device_node *of_get_stdout(void) { return of_stdout; } int of_write_prop(struct device_node *np, const char *propname, int len, const void *value) { struct property *pp; struct property *pp_last = NULL; struct property *new; if (!np) return -EINVAL; for (pp = np->properties; pp; pp = pp->next) { if (strcmp(pp->name, propname) == 0) { /* Property exists -> change value */ pp->value = (void *)value; pp->length = len; return 0; } pp_last = pp; } /* Property does not exist -> append new property */ new = malloc(sizeof(struct property)); if (!new) return -ENOMEM; new->name = strdup(propname); if (!new->name) { free(new); return -ENOMEM; } new->value = (void *)value; new->length = len; new->next = NULL; if (pp_last) pp_last->next = new; else np->properties = new; return 0; } int of_add_subnode(struct device_node *parent, const char *name, int len, struct device_node **childp) { struct device_node *child, *new, *last_sibling = NULL; char *new_name, *full_name; int parent_fnl; if (len == -1) len = strlen(name); __for_each_child_of_node(parent, child) { /* * make sure we don't use a child called "trevor" when we are * searching for "trev". */ if (!strncmp(child->name, name, len) && strlen(name) == len) { *childp = child; return -EEXIST; } last_sibling = child; } /* Subnode does not exist -> append new subnode */ new = calloc(1, sizeof(struct device_node)); if (!new) return -ENOMEM; new_name = memdup(name, len + 1); if (!new_name) { free(new); return -ENOMEM; } new_name[len] = '\0'; /* * if the parent is the root node (named "") we don't need to prepend * its full path */ parent_fnl = *parent->name ? strlen(parent->full_name) : 0; full_name = calloc(1, parent_fnl + 1 + len + 1); if (!full_name) { free(new_name); free(new); return -ENOMEM; } new->name = new_name; /* assign to constant pointer */ strcpy(full_name, parent->full_name); /* "" for root node */ full_name[parent_fnl] = '/'; strlcpy(&full_name[parent_fnl + 1], name, len + 1); new->full_name = full_name; /* Add as last sibling of the parent */ if (last_sibling) last_sibling->sibling = new; if (!parent->child) parent->child = new; new->parent = parent; *childp = new; return 0; } int __of_remove_property(struct device_node *np, struct property *prop) { struct property **next; for (next = &np->properties; *next; next = &(*next)->next) { if (*next == prop) break; } if (!*next) return -ENODEV; /* found the node */ *next = prop->next; return 0; } int of_remove_property(struct device_node *np, struct property *prop) { int rc; mutex_lock(&of_mutex); rc = __of_remove_property(np, prop); mutex_unlock(&of_mutex); return rc; } int of_remove_node(struct device_node *to_remove) { struct device_node *parent = to_remove->parent; struct device_node *np, *prev; if (!parent) return -EPERM; prev = NULL; __for_each_child_of_node(parent, np) { if (np == to_remove) break; prev = np; } if (!np) return -EFAULT; /* if there is a previous node, link it to this one's sibling */ if (prev) prev->sibling = np->sibling; else parent->child = np->sibling; /* * don't free it, since if this is an unflattened tree, all the memory * was alloced in one block; this pointer will be somewhere in the * middle of that * * TODO(sjg@chromium.org): Consider marking nodes as 'allocated'? * * free(np); */ return 0; }