/* * Copyright (c) 2006-2023, RT-Thread Development Team * * SPDX-License-Identifier: Apache-2.0 */ #include "libfdt.h" #include "dtb_node.h" /* "/aliaes" node */ static struct dtb_node *fdt_aliases; /** * 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, -ENODATA if property does not have a value, and -EOVERFLOW if the * property data isn't large enough. */ static void *dtb_node_find_property_value_of_size(const struct dtb_node *dn, const char *propname, uint32_t len) { struct dtb_property *prop = dtb_node_get_dtb_node_property(dn, propname, NULL); if (!prop) return DTB_ERR_PTR(-EINVAL); if (!prop->value) return DTB_ERR_PTR(-ENODATA); if (len > prop->size) return DTB_ERR_PTR(-EOVERFLOW); return prop->value; } int dtb_node_read_u32(const struct dtb_node *dn, const char *propname, uint32_t *outp) { const uint32_t *val; debug("%s: %s: \n", __func__, propname); if (!dn) return -EINVAL; val = dtb_node_find_property_value_of_size(dn, propname, sizeof(*outp)); if (DTB_IS_ERR(val)) { debug("(not found)\n"); return DTB_PTR_ERR(val); } *outp = fdt32_to_cpu(*val); debug("%#x (%d)\n", *outp, *outp); return 0; } uint32_t dtb_node_read_u32_default(const struct dtb_node *node, const char *propname, uint32_t def) { dtb_node_read_u32(node, propname, &def); return def; } int dtb_node_read_u32_array(const struct dtb_node *dn, const char *propname, uint32_t *out_values, size_t sz) { const uint32_t *val; debug("%s: %s: ", __func__, propname); val = dtb_node_find_property_value_of_size(dn, propname, sz * sizeof(*out_values)); if (DTB_IS_ERR(val)) return DTB_PTR_ERR(val); debug("size %zd, val:%d\n", sz, *val); while (sz--) *out_values++ = fdt32_to_cpu(*val++); return 0; } uint32_t dtb_node_read_u32_index_default(const struct dtb_node *node, const char *propname, int index, uint32_t def) { RT_ASSERT(dtb_node_valid(node)); dtb_node_read_u32_index(node, propname, index, &def); return def; } int dtb_node_read_s32_default(const struct dtb_node *node, const char *propname, int32_t def) { RT_ASSERT(dtb_node_valid(node)); dtb_node_read_u32(node, propname, (uint32_t *)&def); return def; } int dtb_node_read_u32_index(const struct dtb_node *dn, const char *propname, int index, uint32_t *outp) { const uint32_t *val; debug("%s: %s: ", __func__, propname); if (!dn) return -EINVAL; val = dtb_node_find_property_value_of_size(dn, propname, sizeof(*outp) * (index + 1)); if (DTB_IS_ERR(val)) { debug("(not found)\n"); return DTB_PTR_ERR(val); } *outp = fdt32_to_cpu(val[index]); debug("%#x (%d)\n", *outp, *outp); return 0; } int dtb_node_read_u64(const struct dtb_node *dn, const char *propname, uint64_t *outp) { const uint64_t *val; debug("%s: %s: ", __func__, propname); if (!dn) return -EINVAL; val = dtb_node_find_property_value_of_size(dn, propname, sizeof(*outp)); if (DTB_IS_ERR(val)) { debug("(not found)\n"); return DTB_PTR_ERR(val); } *outp = fdt64_to_cpu(*val); debug("%#llx (%lld)\n", (unsigned long long)*outp, (unsigned long long)*outp); return 0; } uint64_t dtb_node_read_u64_default(const struct dtb_node *node, const char *propname, uint64_t def) { RT_ASSERT(dtb_node_valid(node)); dtb_node_read_u64(node, propname, &def); return def; } int dtb_node_n_addr_cells(const struct dtb_node *dn) { const uint32_t *ip; do { if (dn->parent) dn = dn->parent; ip = dtb_node_get_dtb_node_property_value(dn, "#address-cells", NULL); if (ip) return fdt32_to_cpu(*ip); } while (dn->parent); /* No #address-cells property for the root node */ return DEV_ROOT_NODE_ADDR_CELLS_DEFAULT; } int dtb_node_n_size_cells(const struct dtb_node *dn) { const uint32_t *ip; do { if (dn->parent) dn = dn->parent; ip = dtb_node_get_dtb_node_property_value(dn, "#size-cells", NULL); if (ip) return fdt32_to_cpu(*ip); } while (dn->parent); /* No #size-cells property for the root node */ return DEV_ROOT_NODE_SIZE_CELLS_DEFAULT; } int dtb_node_simple_addr_cells(const struct dtb_node *dn) { const uint32_t *ip; ip = dtb_node_get_dtb_node_property_value(dn, "#address-cells", NULL); if (ip) return fdt32_to_cpu(*ip); /* Return a default of 2 to match fdt_address_cells()*/ return 2; } int dtb_node_simple_size_cells(const struct dtb_node *dn) { const uint32_t *ip; ip = dtb_node_get_dtb_node_property_value(dn, "#size-cells", NULL); if (ip) return fdt32_to_cpu(*ip); /* Return a default of 2 to match fdt_size_cells()*/ return 2; } struct dtb_property *dtb_node_get_dtb_node_property(const struct dtb_node *dtb_node, const char *property_name, int *property_size) { struct dtb_property *dtb_property = NULL; if (dtb_node != NULL && property_name != NULL) { dtb_property = dtb_node->properties; while (dtb_property != NULL) { if (!strcmp(dtb_property->name, property_name)) { if (property_size != NULL) { *property_size = dtb_property->size; } return dtb_property; } dtb_property = dtb_property->next; } } return dtb_property; } #define for_each_property_of_node(dn, pp) \ for (pp = dn->properties; pp != NULL; pp = pp->next) struct dtb_node *dtb_node_find_node_opts_by_path(const char *path, const char **opts) { struct dtb_node *np = NULL; struct dtb_property *pp; const char *separator = strchr(path, ':'); if (opts) *opts = separator ? separator + 1 : NULL; if (strcmp(path, "/") == 0) return dtb_node_get(get_dtb_node_head()); /* The path could begin with an alias */ if (*path != '/') { int len; const char *p = separator; if (!p) p = strchrnul(path, '/'); len = p - path; /* of_aliases must not be NULL */ if (!fdt_aliases) return NULL; for_each_property_of_node(fdt_aliases, pp) { if (strlen(pp->name) == len && !strncmp(pp->name, path, len)) { np = dtb_node_find_node_by_path(pp->value); break; } } if (!np) return NULL; path = p; } /* Step down the tree matching path components */ if (!np) np = dtb_node_get(get_dtb_node_head()); while (np && *path == '/') { struct dtb_node *tmp = np; path++; /* Increment past '/' delimiter */ np = dtb_node_get_dtb_node_by_path(np, path); dtb_node_put(tmp); path = strchrnul(path, '/'); if (separator && separator < path) break; } return np; } struct dtb_node *dtb_node_find_compatible_node(struct dtb_node *from, const char *compatible) { struct dtb_node *dn; for_each_of_allnodes_from(from, dn) { if (dtb_node_get_dtb_node_compatible_match(dn, compatible) && dtb_node_get(dn)) break; } dtb_node_put(from); return dn; } void *dtb_node_get_dtb_node_property_value(const struct dtb_node *dtb_node, const char *property_name, int *property_size) { struct dtb_property *dtb_property = dtb_node_get_dtb_node_property(dtb_node, property_name, NULL); if (!dtb_property || !dtb_property->value || !dtb_property->size) { return NULL; } if (property_size != NULL) { *property_size = dtb_property->size; } return dtb_property->value; } const struct dtb_node *dtb_node_find_node_by_prop_value(struct dtb_node *from, const char *propname, const void *propval, int proplen) { struct dtb_node *np; void *value; for_each_of_allnodes_from(from, np) { value = dtb_node_get_dtb_node_property_value(np, propname, &proplen); if (!memcmp(value, propval, proplen) && dtb_node_get(np)) break; } dtb_node_put(from); return np; } struct dtb_node *dtb_node_find_all_nodes(const struct dtb_node *prev) { const struct dtb_node *dn; if (!prev) { dn = get_dtb_node_head(); } else if (prev->child) { dn = prev->child; } else { /* * Walk back up looking for a sibling, or the end of the * structure */ dn = prev; while (dn->parent && !dn->sibling) dn = dn->parent; dn = dn->sibling; /* Might be null at the end of the tree */ } return (struct dtb_node *)dn; } rt_bool_t dtb_node_device_is_available(const struct dtb_node *device) { const char *status; int statlen; if (!device) return RT_FALSE; status = dtb_node_get_dtb_node_property_value(device, "status", &statlen); if (status == NULL) return RT_TRUE; if (statlen > 0) { if (!strcmp(status, "okay")) return RT_TRUE; } return RT_FALSE; } struct dtb_node *dtb_node_get_parent(const struct dtb_node *node) { const struct dtb_node *dn; if (!node) return NULL; dn = dtb_node_get(node->parent); return (struct dtb_node *)dn; } struct dtb_node *dtb_node_find_node_by_phandle(phandle handle) { struct dtb_node *dn; if (!handle) return NULL; for_each_of_allnodes(dn) if (dn->handle == handle) break; (void)dtb_node_get(dn); return dn; } int dtb_node_property_match_string(const struct dtb_node *dn, const char *propname, const char *string) { const struct dtb_property *prop = dtb_node_get_dtb_node_property(dn, propname, NULL); size_t l; int i; const char *p, *end; if (!prop) return -EINVAL; if (!prop->value) return -ENODATA; p = prop->value; end = p + prop->size; 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. * * Don't call this function directly. It is a utility helper for the * of_property_read_string*() family of functions. */ int dtb_node_property_read_string_helper(const struct dtb_node *dn, const char *propname, const char **out_strs, size_t sz, int skip) { const struct dtb_property *prop = dtb_node_get_dtb_node_property(dn, 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->size; 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 __dtb_node_parse_phandle_with_args(const struct dtb_node *dn, const char *list_name, const char *cells_name, int cell_count, int index, struct fdt_phandle_args *out_args) { const uint32_t *list, *list_end; int rc = 0, cur_index = 0; uint32_t count = 0; struct dtb_node *node = NULL; phandle phandle; int size; /* Retrieve the phandle list property */ list = dtb_node_get_dtb_node_property_value(dn, 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 = fdt32_to_cpu(*(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 = dtb_node_find_node_by_phandle(phandle); if (!node) { debug("%s: could not find phandle\n", dn->path); goto err; } } if (cells_name) { if (dtb_node_read_u32(node, cells_name, &count)) { debug("%s: could not get %s for %s\n", dn->path, cells_name, node->path); 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", dn->path); 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 (count > FDT_MAX_PHANDLE_ARGS) count = FDT_MAX_PHANDLE_ARGS; out_args->np = node; out_args->args_count = count; for (i = 0; i < count; i++) out_args->args[i] = fdt32_to_cpu(*(list++)); } else { dtb_node_put(node); } /* Found it! return success */ return 0; } dtb_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) dtb_node_put(node); return rc; } struct dtb_node *dtb_node_parse_phandle(const struct dtb_node *dn, const char *phandle_name, int index) { struct fdt_phandle_args args; if (index < 0) return NULL; if (__dtb_node_parse_phandle_with_args(dn, phandle_name, NULL, 0, index, &args)) return NULL; return args.np; } int dtb_node_parse_phandle_with_args(const struct dtb_node *dn, const char *list_name, const char *cells_name, int index, struct fdt_phandle_args *out_args) { if (index < 0) return -EINVAL; return __dtb_node_parse_phandle_with_args(dn, list_name, cells_name, 0, index, out_args); } int dtb_node_count_phandle_with_args(const struct dtb_node *dn, const char *list_name, const char *cells_name) { return __dtb_node_parse_phandle_with_args(dn, list_name, cells_name, 0, -1, NULL); }