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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /scripts/dtc/libfdt/fdt_ro.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'scripts/dtc/libfdt/fdt_ro.c')
-rw-r--r--scripts/dtc/libfdt/fdt_ro.c859
1 files changed, 859 insertions, 0 deletions
diff --git a/scripts/dtc/libfdt/fdt_ro.c b/scripts/dtc/libfdt/fdt_ro.c
new file mode 100644
index 000000000..91cc6fefe
--- /dev/null
+++ b/scripts/dtc/libfdt/fdt_ro.c
@@ -0,0 +1,859 @@
+// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
+/*
+ * libfdt - Flat Device Tree manipulation
+ * Copyright (C) 2006 David Gibson, IBM Corporation.
+ */
+#include "libfdt_env.h"
+
+#include <fdt.h>
+#include <libfdt.h>
+
+#include "libfdt_internal.h"
+
+static int fdt_nodename_eq_(const void *fdt, int offset,
+ const char *s, int len)
+{
+ int olen;
+ const char *p = fdt_get_name(fdt, offset, &olen);
+
+ if (!p || olen < len)
+ /* short match */
+ return 0;
+
+ if (memcmp(p, s, len) != 0)
+ return 0;
+
+ if (p[len] == '\0')
+ return 1;
+ else if (!memchr(s, '@', len) && (p[len] == '@'))
+ return 1;
+ else
+ return 0;
+}
+
+const char *fdt_get_string(const void *fdt, int stroffset, int *lenp)
+{
+ int32_t totalsize;
+ uint32_t absoffset;
+ size_t len;
+ int err;
+ const char *s, *n;
+
+ if (can_assume(VALID_INPUT)) {
+ s = (const char *)fdt + fdt_off_dt_strings(fdt) + stroffset;
+
+ if (lenp)
+ *lenp = strlen(s);
+ return s;
+ }
+ totalsize = fdt_ro_probe_(fdt);
+ err = totalsize;
+ if (totalsize < 0)
+ goto fail;
+
+ err = -FDT_ERR_BADOFFSET;
+ absoffset = stroffset + fdt_off_dt_strings(fdt);
+ if (absoffset >= (unsigned)totalsize)
+ goto fail;
+ len = totalsize - absoffset;
+
+ if (fdt_magic(fdt) == FDT_MAGIC) {
+ if (stroffset < 0)
+ goto fail;
+ if (can_assume(LATEST) || fdt_version(fdt) >= 17) {
+ if ((unsigned)stroffset >= fdt_size_dt_strings(fdt))
+ goto fail;
+ if ((fdt_size_dt_strings(fdt) - stroffset) < len)
+ len = fdt_size_dt_strings(fdt) - stroffset;
+ }
+ } else if (fdt_magic(fdt) == FDT_SW_MAGIC) {
+ unsigned int sw_stroffset = -stroffset;
+
+ if ((stroffset >= 0) ||
+ (sw_stroffset > fdt_size_dt_strings(fdt)))
+ goto fail;
+ if (sw_stroffset < len)
+ len = sw_stroffset;
+ } else {
+ err = -FDT_ERR_INTERNAL;
+ goto fail;
+ }
+
+ s = (const char *)fdt + absoffset;
+ n = memchr(s, '\0', len);
+ if (!n) {
+ /* missing terminating NULL */
+ err = -FDT_ERR_TRUNCATED;
+ goto fail;
+ }
+
+ if (lenp)
+ *lenp = n - s;
+ return s;
+
+fail:
+ if (lenp)
+ *lenp = err;
+ return NULL;
+}
+
+const char *fdt_string(const void *fdt, int stroffset)
+{
+ return fdt_get_string(fdt, stroffset, NULL);
+}
+
+static int fdt_string_eq_(const void *fdt, int stroffset,
+ const char *s, int len)
+{
+ int slen;
+ const char *p = fdt_get_string(fdt, stroffset, &slen);
+
+ return p && (slen == len) && (memcmp(p, s, len) == 0);
+}
+
+int fdt_find_max_phandle(const void *fdt, uint32_t *phandle)
+{
+ uint32_t max = 0;
+ int offset = -1;
+
+ while (true) {
+ uint32_t value;
+
+ offset = fdt_next_node(fdt, offset, NULL);
+ if (offset < 0) {
+ if (offset == -FDT_ERR_NOTFOUND)
+ break;
+
+ return offset;
+ }
+
+ value = fdt_get_phandle(fdt, offset);
+
+ if (value > max)
+ max = value;
+ }
+
+ if (phandle)
+ *phandle = max;
+
+ return 0;
+}
+
+int fdt_generate_phandle(const void *fdt, uint32_t *phandle)
+{
+ uint32_t max;
+ int err;
+
+ err = fdt_find_max_phandle(fdt, &max);
+ if (err < 0)
+ return err;
+
+ if (max == FDT_MAX_PHANDLE)
+ return -FDT_ERR_NOPHANDLES;
+
+ if (phandle)
+ *phandle = max + 1;
+
+ return 0;
+}
+
+static const struct fdt_reserve_entry *fdt_mem_rsv(const void *fdt, int n)
+{
+ unsigned int offset = n * sizeof(struct fdt_reserve_entry);
+ unsigned int absoffset = fdt_off_mem_rsvmap(fdt) + offset;
+
+ if (!can_assume(VALID_INPUT)) {
+ if (absoffset < fdt_off_mem_rsvmap(fdt))
+ return NULL;
+ if (absoffset > fdt_totalsize(fdt) -
+ sizeof(struct fdt_reserve_entry))
+ return NULL;
+ }
+ return fdt_mem_rsv_(fdt, n);
+}
+
+int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size)
+{
+ const struct fdt_reserve_entry *re;
+
+ FDT_RO_PROBE(fdt);
+ re = fdt_mem_rsv(fdt, n);
+ if (!can_assume(VALID_INPUT) && !re)
+ return -FDT_ERR_BADOFFSET;
+
+ *address = fdt64_ld(&re->address);
+ *size = fdt64_ld(&re->size);
+ return 0;
+}
+
+int fdt_num_mem_rsv(const void *fdt)
+{
+ int i;
+ const struct fdt_reserve_entry *re;
+
+ for (i = 0; (re = fdt_mem_rsv(fdt, i)) != NULL; i++) {
+ if (fdt64_ld(&re->size) == 0)
+ return i;
+ }
+ return -FDT_ERR_TRUNCATED;
+}
+
+static int nextprop_(const void *fdt, int offset)
+{
+ uint32_t tag;
+ int nextoffset;
+
+ do {
+ tag = fdt_next_tag(fdt, offset, &nextoffset);
+
+ switch (tag) {
+ case FDT_END:
+ if (nextoffset >= 0)
+ return -FDT_ERR_BADSTRUCTURE;
+ else
+ return nextoffset;
+
+ case FDT_PROP:
+ return offset;
+ }
+ offset = nextoffset;
+ } while (tag == FDT_NOP);
+
+ return -FDT_ERR_NOTFOUND;
+}
+
+int fdt_subnode_offset_namelen(const void *fdt, int offset,
+ const char *name, int namelen)
+{
+ int depth;
+
+ FDT_RO_PROBE(fdt);
+
+ for (depth = 0;
+ (offset >= 0) && (depth >= 0);
+ offset = fdt_next_node(fdt, offset, &depth))
+ if ((depth == 1)
+ && fdt_nodename_eq_(fdt, offset, name, namelen))
+ return offset;
+
+ if (depth < 0)
+ return -FDT_ERR_NOTFOUND;
+ return offset; /* error */
+}
+
+int fdt_subnode_offset(const void *fdt, int parentoffset,
+ const char *name)
+{
+ return fdt_subnode_offset_namelen(fdt, parentoffset, name, strlen(name));
+}
+
+int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen)
+{
+ const char *end = path + namelen;
+ const char *p = path;
+ int offset = 0;
+
+ FDT_RO_PROBE(fdt);
+
+ /* see if we have an alias */
+ if (*path != '/') {
+ const char *q = memchr(path, '/', end - p);
+
+ if (!q)
+ q = end;
+
+ p = fdt_get_alias_namelen(fdt, p, q - p);
+ if (!p)
+ return -FDT_ERR_BADPATH;
+ offset = fdt_path_offset(fdt, p);
+
+ p = q;
+ }
+
+ while (p < end) {
+ const char *q;
+
+ while (*p == '/') {
+ p++;
+ if (p == end)
+ return offset;
+ }
+ q = memchr(p, '/', end - p);
+ if (! q)
+ q = end;
+
+ offset = fdt_subnode_offset_namelen(fdt, offset, p, q-p);
+ if (offset < 0)
+ return offset;
+
+ p = q;
+ }
+
+ return offset;
+}
+
+int fdt_path_offset(const void *fdt, const char *path)
+{
+ return fdt_path_offset_namelen(fdt, path, strlen(path));
+}
+
+const char *fdt_get_name(const void *fdt, int nodeoffset, int *len)
+{
+ const struct fdt_node_header *nh = fdt_offset_ptr_(fdt, nodeoffset);
+ const char *nameptr;
+ int err;
+
+ if (((err = fdt_ro_probe_(fdt)) < 0)
+ || ((err = fdt_check_node_offset_(fdt, nodeoffset)) < 0))
+ goto fail;
+
+ nameptr = nh->name;
+
+ if (!can_assume(LATEST) && fdt_version(fdt) < 0x10) {
+ /*
+ * For old FDT versions, match the naming conventions of V16:
+ * give only the leaf name (after all /). The actual tree
+ * contents are loosely checked.
+ */
+ const char *leaf;
+ leaf = strrchr(nameptr, '/');
+ if (leaf == NULL) {
+ err = -FDT_ERR_BADSTRUCTURE;
+ goto fail;
+ }
+ nameptr = leaf+1;
+ }
+
+ if (len)
+ *len = strlen(nameptr);
+
+ return nameptr;
+
+ fail:
+ if (len)
+ *len = err;
+ return NULL;
+}
+
+int fdt_first_property_offset(const void *fdt, int nodeoffset)
+{
+ int offset;
+
+ if ((offset = fdt_check_node_offset_(fdt, nodeoffset)) < 0)
+ return offset;
+
+ return nextprop_(fdt, offset);
+}
+
+int fdt_next_property_offset(const void *fdt, int offset)
+{
+ if ((offset = fdt_check_prop_offset_(fdt, offset)) < 0)
+ return offset;
+
+ return nextprop_(fdt, offset);
+}
+
+static const struct fdt_property *fdt_get_property_by_offset_(const void *fdt,
+ int offset,
+ int *lenp)
+{
+ int err;
+ const struct fdt_property *prop;
+
+ if (!can_assume(VALID_INPUT) &&
+ (err = fdt_check_prop_offset_(fdt, offset)) < 0) {
+ if (lenp)
+ *lenp = err;
+ return NULL;
+ }
+
+ prop = fdt_offset_ptr_(fdt, offset);
+
+ if (lenp)
+ *lenp = fdt32_ld(&prop->len);
+
+ return prop;
+}
+
+const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
+ int offset,
+ int *lenp)
+{
+ /* Prior to version 16, properties may need realignment
+ * and this API does not work. fdt_getprop_*() will, however. */
+
+ if (!can_assume(LATEST) && fdt_version(fdt) < 0x10) {
+ if (lenp)
+ *lenp = -FDT_ERR_BADVERSION;
+ return NULL;
+ }
+
+ return fdt_get_property_by_offset_(fdt, offset, lenp);
+}
+
+static const struct fdt_property *fdt_get_property_namelen_(const void *fdt,
+ int offset,
+ const char *name,
+ int namelen,
+ int *lenp,
+ int *poffset)
+{
+ for (offset = fdt_first_property_offset(fdt, offset);
+ (offset >= 0);
+ (offset = fdt_next_property_offset(fdt, offset))) {
+ const struct fdt_property *prop;
+
+ prop = fdt_get_property_by_offset_(fdt, offset, lenp);
+ if (!can_assume(LIBFDT_FLAWLESS) && !prop) {
+ offset = -FDT_ERR_INTERNAL;
+ break;
+ }
+ if (fdt_string_eq_(fdt, fdt32_ld(&prop->nameoff),
+ name, namelen)) {
+ if (poffset)
+ *poffset = offset;
+ return prop;
+ }
+ }
+
+ if (lenp)
+ *lenp = offset;
+ return NULL;
+}
+
+
+const struct fdt_property *fdt_get_property_namelen(const void *fdt,
+ int offset,
+ const char *name,
+ int namelen, int *lenp)
+{
+ /* Prior to version 16, properties may need realignment
+ * and this API does not work. fdt_getprop_*() will, however. */
+ if (!can_assume(LATEST) && fdt_version(fdt) < 0x10) {
+ if (lenp)
+ *lenp = -FDT_ERR_BADVERSION;
+ return NULL;
+ }
+
+ return fdt_get_property_namelen_(fdt, offset, name, namelen, lenp,
+ NULL);
+}
+
+
+const struct fdt_property *fdt_get_property(const void *fdt,
+ int nodeoffset,
+ const char *name, int *lenp)
+{
+ return fdt_get_property_namelen(fdt, nodeoffset, name,
+ strlen(name), lenp);
+}
+
+const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
+ const char *name, int namelen, int *lenp)
+{
+ int poffset;
+ const struct fdt_property *prop;
+
+ prop = fdt_get_property_namelen_(fdt, nodeoffset, name, namelen, lenp,
+ &poffset);
+ if (!prop)
+ return NULL;
+
+ /* Handle realignment */
+ if (!can_assume(LATEST) && fdt_version(fdt) < 0x10 &&
+ (poffset + sizeof(*prop)) % 8 && fdt32_ld(&prop->len) >= 8)
+ return prop->data + 4;
+ return prop->data;
+}
+
+const void *fdt_getprop_by_offset(const void *fdt, int offset,
+ const char **namep, int *lenp)
+{
+ const struct fdt_property *prop;
+
+ prop = fdt_get_property_by_offset_(fdt, offset, lenp);
+ if (!prop)
+ return NULL;
+ if (namep) {
+ const char *name;
+ int namelen;
+
+ if (!can_assume(VALID_INPUT)) {
+ name = fdt_get_string(fdt, fdt32_ld(&prop->nameoff),
+ &namelen);
+ if (!name) {
+ if (lenp)
+ *lenp = namelen;
+ return NULL;
+ }
+ *namep = name;
+ } else {
+ *namep = fdt_string(fdt, fdt32_ld(&prop->nameoff));
+ }
+ }
+
+ /* Handle realignment */
+ if (!can_assume(LATEST) && fdt_version(fdt) < 0x10 &&
+ (offset + sizeof(*prop)) % 8 && fdt32_ld(&prop->len) >= 8)
+ return prop->data + 4;
+ return prop->data;
+}
+
+const void *fdt_getprop(const void *fdt, int nodeoffset,
+ const char *name, int *lenp)
+{
+ return fdt_getprop_namelen(fdt, nodeoffset, name, strlen(name), lenp);
+}
+
+uint32_t fdt_get_phandle(const void *fdt, int nodeoffset)
+{
+ const fdt32_t *php;
+ int len;
+
+ /* FIXME: This is a bit sub-optimal, since we potentially scan
+ * over all the properties twice. */
+ php = fdt_getprop(fdt, nodeoffset, "phandle", &len);
+ if (!php || (len != sizeof(*php))) {
+ php = fdt_getprop(fdt, nodeoffset, "linux,phandle", &len);
+ if (!php || (len != sizeof(*php)))
+ return 0;
+ }
+
+ return fdt32_ld(php);
+}
+
+const char *fdt_get_alias_namelen(const void *fdt,
+ const char *name, int namelen)
+{
+ int aliasoffset;
+
+ aliasoffset = fdt_path_offset(fdt, "/aliases");
+ if (aliasoffset < 0)
+ return NULL;
+
+ return fdt_getprop_namelen(fdt, aliasoffset, name, namelen, NULL);
+}
+
+const char *fdt_get_alias(const void *fdt, const char *name)
+{
+ return fdt_get_alias_namelen(fdt, name, strlen(name));
+}
+
+int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen)
+{
+ int pdepth = 0, p = 0;
+ int offset, depth, namelen;
+ const char *name;
+
+ FDT_RO_PROBE(fdt);
+
+ if (buflen < 2)
+ return -FDT_ERR_NOSPACE;
+
+ for (offset = 0, depth = 0;
+ (offset >= 0) && (offset <= nodeoffset);
+ offset = fdt_next_node(fdt, offset, &depth)) {
+ while (pdepth > depth) {
+ do {
+ p--;
+ } while (buf[p-1] != '/');
+ pdepth--;
+ }
+
+ if (pdepth >= depth) {
+ name = fdt_get_name(fdt, offset, &namelen);
+ if (!name)
+ return namelen;
+ if ((p + namelen + 1) <= buflen) {
+ memcpy(buf + p, name, namelen);
+ p += namelen;
+ buf[p++] = '/';
+ pdepth++;
+ }
+ }
+
+ if (offset == nodeoffset) {
+ if (pdepth < (depth + 1))
+ return -FDT_ERR_NOSPACE;
+
+ if (p > 1) /* special case so that root path is "/", not "" */
+ p--;
+ buf[p] = '\0';
+ return 0;
+ }
+ }
+
+ if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
+ return -FDT_ERR_BADOFFSET;
+ else if (offset == -FDT_ERR_BADOFFSET)
+ return -FDT_ERR_BADSTRUCTURE;
+
+ return offset; /* error from fdt_next_node() */
+}
+
+int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
+ int supernodedepth, int *nodedepth)
+{
+ int offset, depth;
+ int supernodeoffset = -FDT_ERR_INTERNAL;
+
+ FDT_RO_PROBE(fdt);
+
+ if (supernodedepth < 0)
+ return -FDT_ERR_NOTFOUND;
+
+ for (offset = 0, depth = 0;
+ (offset >= 0) && (offset <= nodeoffset);
+ offset = fdt_next_node(fdt, offset, &depth)) {
+ if (depth == supernodedepth)
+ supernodeoffset = offset;
+
+ if (offset == nodeoffset) {
+ if (nodedepth)
+ *nodedepth = depth;
+
+ if (supernodedepth > depth)
+ return -FDT_ERR_NOTFOUND;
+ else
+ return supernodeoffset;
+ }
+ }
+
+ if (!can_assume(VALID_INPUT)) {
+ if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
+ return -FDT_ERR_BADOFFSET;
+ else if (offset == -FDT_ERR_BADOFFSET)
+ return -FDT_ERR_BADSTRUCTURE;
+ }
+
+ return offset; /* error from fdt_next_node() */
+}
+
+int fdt_node_depth(const void *fdt, int nodeoffset)
+{
+ int nodedepth;
+ int err;
+
+ err = fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, &nodedepth);
+ if (err)
+ return (can_assume(LIBFDT_FLAWLESS) || err < 0) ? err :
+ -FDT_ERR_INTERNAL;
+ return nodedepth;
+}
+
+int fdt_parent_offset(const void *fdt, int nodeoffset)
+{
+ int nodedepth = fdt_node_depth(fdt, nodeoffset);
+
+ if (nodedepth < 0)
+ return nodedepth;
+ return fdt_supernode_atdepth_offset(fdt, nodeoffset,
+ nodedepth - 1, NULL);
+}
+
+int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
+ const char *propname,
+ const void *propval, int proplen)
+{
+ int offset;
+ const void *val;
+ int len;
+
+ FDT_RO_PROBE(fdt);
+
+ /* FIXME: The algorithm here is pretty horrible: we scan each
+ * property of a node in fdt_getprop(), then if that didn't
+ * find what we want, we scan over them again making our way
+ * to the next node. Still it's the easiest to implement
+ * approach; performance can come later. */
+ for (offset = fdt_next_node(fdt, startoffset, NULL);
+ offset >= 0;
+ offset = fdt_next_node(fdt, offset, NULL)) {
+ val = fdt_getprop(fdt, offset, propname, &len);
+ if (val && (len == proplen)
+ && (memcmp(val, propval, len) == 0))
+ return offset;
+ }
+
+ return offset; /* error from fdt_next_node() */
+}
+
+int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle)
+{
+ int offset;
+
+ if ((phandle == 0) || (phandle == ~0U))
+ return -FDT_ERR_BADPHANDLE;
+
+ FDT_RO_PROBE(fdt);
+
+ /* FIXME: The algorithm here is pretty horrible: we
+ * potentially scan each property of a node in
+ * fdt_get_phandle(), then if that didn't find what
+ * we want, we scan over them again making our way to the next
+ * node. Still it's the easiest to implement approach;
+ * performance can come later. */
+ for (offset = fdt_next_node(fdt, -1, NULL);
+ offset >= 0;
+ offset = fdt_next_node(fdt, offset, NULL)) {
+ if (fdt_get_phandle(fdt, offset) == phandle)
+ return offset;
+ }
+
+ return offset; /* error from fdt_next_node() */
+}
+
+int fdt_stringlist_contains(const char *strlist, int listlen, const char *str)
+{
+ int len = strlen(str);
+ const char *p;
+
+ while (listlen >= len) {
+ if (memcmp(str, strlist, len+1) == 0)
+ return 1;
+ p = memchr(strlist, '\0', listlen);
+ if (!p)
+ return 0; /* malformed strlist.. */
+ listlen -= (p-strlist) + 1;
+ strlist = p + 1;
+ }
+ return 0;
+}
+
+int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property)
+{
+ const char *list, *end;
+ int length, count = 0;
+
+ list = fdt_getprop(fdt, nodeoffset, property, &length);
+ if (!list)
+ return length;
+
+ end = list + length;
+
+ while (list < end) {
+ length = strnlen(list, end - list) + 1;
+
+ /* Abort if the last string isn't properly NUL-terminated. */
+ if (list + length > end)
+ return -FDT_ERR_BADVALUE;
+
+ list += length;
+ count++;
+ }
+
+ return count;
+}
+
+int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
+ const char *string)
+{
+ int length, len, idx = 0;
+ const char *list, *end;
+
+ list = fdt_getprop(fdt, nodeoffset, property, &length);
+ if (!list)
+ return length;
+
+ len = strlen(string) + 1;
+ end = list + length;
+
+ while (list < end) {
+ length = strnlen(list, end - list) + 1;
+
+ /* Abort if the last string isn't properly NUL-terminated. */
+ if (list + length > end)
+ return -FDT_ERR_BADVALUE;
+
+ if (length == len && memcmp(list, string, length) == 0)
+ return idx;
+
+ list += length;
+ idx++;
+ }
+
+ return -FDT_ERR_NOTFOUND;
+}
+
+const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
+ const char *property, int idx,
+ int *lenp)
+{
+ const char *list, *end;
+ int length;
+
+ list = fdt_getprop(fdt, nodeoffset, property, &length);
+ if (!list) {
+ if (lenp)
+ *lenp = length;
+
+ return NULL;
+ }
+
+ end = list + length;
+
+ while (list < end) {
+ length = strnlen(list, end - list) + 1;
+
+ /* Abort if the last string isn't properly NUL-terminated. */
+ if (list + length > end) {
+ if (lenp)
+ *lenp = -FDT_ERR_BADVALUE;
+
+ return NULL;
+ }
+
+ if (idx == 0) {
+ if (lenp)
+ *lenp = length - 1;
+
+ return list;
+ }
+
+ list += length;
+ idx--;
+ }
+
+ if (lenp)
+ *lenp = -FDT_ERR_NOTFOUND;
+
+ return NULL;
+}
+
+int fdt_node_check_compatible(const void *fdt, int nodeoffset,
+ const char *compatible)
+{
+ const void *prop;
+ int len;
+
+ prop = fdt_getprop(fdt, nodeoffset, "compatible", &len);
+ if (!prop)
+ return len;
+
+ return !fdt_stringlist_contains(prop, len, compatible);
+}
+
+int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
+ const char *compatible)
+{
+ int offset, err;
+
+ FDT_RO_PROBE(fdt);
+
+ /* FIXME: The algorithm here is pretty horrible: we scan each
+ * property of a node in fdt_node_check_compatible(), then if
+ * that didn't find what we want, we scan over them again
+ * making our way to the next node. Still it's the easiest to
+ * implement approach; performance can come later. */
+ for (offset = fdt_next_node(fdt, startoffset, NULL);
+ offset >= 0;
+ offset = fdt_next_node(fdt, offset, NULL)) {
+ err = fdt_node_check_compatible(fdt, offset, compatible);
+ if ((err < 0) && (err != -FDT_ERR_NOTFOUND))
+ return err;
+ else if (err == 0)
+ return offset;
+ }
+
+ return offset; /* error from fdt_next_node() */
+}