1 // SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
3 * libfdt - Flat Device Tree manipulation
4 * Copyright (C) 2006 David Gibson, IBM Corporation.
6 #include "libfdt_env.h"
11 #include "libfdt_internal.h"
13 static int fdt_blocks_misordered_(const void *fdt,
14 int mem_rsv_size, int struct_size)
16 return (fdt_off_mem_rsvmap(fdt) < FDT_ALIGN(sizeof(struct fdt_header), 8))
17 || (fdt_off_dt_struct(fdt) <
18 (fdt_off_mem_rsvmap(fdt) + mem_rsv_size))
19 || (fdt_off_dt_strings(fdt) <
20 (fdt_off_dt_struct(fdt) + struct_size))
21 || (fdt_totalsize(fdt) <
22 (fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt)));
25 static int fdt_rw_probe_(void *fdt)
27 if (can_assume(VALID_DTB))
31 if (!can_assume(LATEST) && fdt_version(fdt) < 17)
32 return -FDT_ERR_BADVERSION;
33 if (fdt_blocks_misordered_(fdt, sizeof(struct fdt_reserve_entry),
34 fdt_size_dt_struct(fdt)))
35 return -FDT_ERR_BADLAYOUT;
36 if (!can_assume(LATEST) && fdt_version(fdt) > 17)
37 fdt_set_version(fdt, 17);
42 #define FDT_RW_PROBE(fdt) \
45 if ((err_ = fdt_rw_probe_(fdt)) != 0) \
49 static inline unsigned int fdt_data_size_(void *fdt)
51 return fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt);
54 static int fdt_splice_(void *fdt, void *splicepoint, int oldlen, int newlen)
56 char *p = splicepoint;
57 unsigned int dsize = fdt_data_size_(fdt);
58 size_t soff = p - (char *)fdt;
60 if ((oldlen < 0) || (soff + oldlen < soff) || (soff + oldlen > dsize))
61 return -FDT_ERR_BADOFFSET;
62 if ((p < (char *)fdt) || (dsize + newlen < (unsigned)oldlen))
63 return -FDT_ERR_BADOFFSET;
64 if (dsize - oldlen + newlen > fdt_totalsize(fdt))
65 return -FDT_ERR_NOSPACE;
66 memmove(p + newlen, p + oldlen, ((char *)fdt + dsize) - (p + oldlen));
70 static int fdt_splice_mem_rsv_(void *fdt, struct fdt_reserve_entry *p,
73 int delta = (newn - oldn) * sizeof(*p);
75 err = fdt_splice_(fdt, p, oldn * sizeof(*p), newn * sizeof(*p));
78 fdt_set_off_dt_struct(fdt, fdt_off_dt_struct(fdt) + delta);
79 fdt_set_off_dt_strings(fdt, fdt_off_dt_strings(fdt) + delta);
83 static int fdt_splice_struct_(void *fdt, void *p,
84 int oldlen, int newlen)
86 int delta = newlen - oldlen;
89 if ((err = fdt_splice_(fdt, p, oldlen, newlen)))
92 fdt_set_size_dt_struct(fdt, fdt_size_dt_struct(fdt) + delta);
93 fdt_set_off_dt_strings(fdt, fdt_off_dt_strings(fdt) + delta);
97 /* Must only be used to roll back in case of error */
98 static void fdt_del_last_string_(void *fdt, const char *s)
100 int newlen = strlen(s) + 1;
102 fdt_set_size_dt_strings(fdt, fdt_size_dt_strings(fdt) - newlen);
105 static int fdt_splice_string_(void *fdt, int newlen)
107 void *p = (char *)fdt
108 + fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt);
111 if ((err = fdt_splice_(fdt, p, 0, newlen)))
114 fdt_set_size_dt_strings(fdt, fdt_size_dt_strings(fdt) + newlen);
119 * fdt_find_add_string_() - Find or allocate a string
121 * @fdt: pointer to the device tree to check/adjust
122 * @s: string to find/add
123 * @allocated: Set to 0 if the string was found, 1 if not found and so
124 * allocated. Ignored if can_assume(NO_ROLLBACK)
125 * @return offset of string in the string table (whether found or added)
127 static int fdt_find_add_string_(void *fdt, const char *s, int *allocated)
129 char *strtab = (char *)fdt + fdt_off_dt_strings(fdt);
132 int len = strlen(s) + 1;
135 if (!can_assume(NO_ROLLBACK))
138 p = fdt_find_string_(strtab, fdt_size_dt_strings(fdt), s);
143 new = strtab + fdt_size_dt_strings(fdt);
144 err = fdt_splice_string_(fdt, len);
148 if (!can_assume(NO_ROLLBACK))
152 return (new - strtab);
155 int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size)
157 struct fdt_reserve_entry *re;
162 re = fdt_mem_rsv_w_(fdt, fdt_num_mem_rsv(fdt));
163 err = fdt_splice_mem_rsv_(fdt, re, 0, 1);
167 re->address = cpu_to_fdt64(address);
168 re->size = cpu_to_fdt64(size);
172 int fdt_del_mem_rsv(void *fdt, int n)
174 struct fdt_reserve_entry *re = fdt_mem_rsv_w_(fdt, n);
178 if (n >= fdt_num_mem_rsv(fdt))
179 return -FDT_ERR_NOTFOUND;
181 return fdt_splice_mem_rsv_(fdt, re, 1, 0);
184 static int fdt_resize_property_(void *fdt, int nodeoffset, const char *name,
185 int len, struct fdt_property **prop)
190 *prop = fdt_get_property_w(fdt, nodeoffset, name, &oldlen);
194 if ((err = fdt_splice_struct_(fdt, (*prop)->data, FDT_TAGALIGN(oldlen),
198 (*prop)->len = cpu_to_fdt32(len);
202 static int fdt_add_property_(void *fdt, int nodeoffset, const char *name,
203 int len, struct fdt_property **prop)
211 if ((nextoffset = fdt_check_node_offset_(fdt, nodeoffset)) < 0)
214 namestroff = fdt_find_add_string_(fdt, name, &allocated);
218 *prop = fdt_offset_ptr_w_(fdt, nextoffset);
219 proplen = sizeof(**prop) + FDT_TAGALIGN(len);
221 err = fdt_splice_struct_(fdt, *prop, 0, proplen);
223 /* Delete the string if we failed to add it */
224 if (!can_assume(NO_ROLLBACK) && allocated)
225 fdt_del_last_string_(fdt, name);
229 (*prop)->tag = cpu_to_fdt32(FDT_PROP);
230 (*prop)->nameoff = cpu_to_fdt32(namestroff);
231 (*prop)->len = cpu_to_fdt32(len);
235 int fdt_set_name(void *fdt, int nodeoffset, const char *name)
243 namep = (char *)(uintptr_t)fdt_get_name(fdt, nodeoffset, &oldlen);
247 newlen = strlen(name);
249 err = fdt_splice_struct_(fdt, namep, FDT_TAGALIGN(oldlen+1),
250 FDT_TAGALIGN(newlen+1));
254 memcpy(namep, name, newlen+1);
258 int fdt_setprop_placeholder(void *fdt, int nodeoffset, const char *name,
259 int len, void **prop_data)
261 struct fdt_property *prop;
266 err = fdt_resize_property_(fdt, nodeoffset, name, len, &prop);
267 if (err == -FDT_ERR_NOTFOUND)
268 err = fdt_add_property_(fdt, nodeoffset, name, len, &prop);
272 *prop_data = prop->data;
276 int fdt_setprop(void *fdt, int nodeoffset, const char *name,
277 const void *val, int len)
282 err = fdt_setprop_placeholder(fdt, nodeoffset, name, len, &prop_data);
287 memcpy(prop_data, val, len);
291 int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
292 const void *val, int len)
294 struct fdt_property *prop;
295 int err, oldlen, newlen;
299 prop = fdt_get_property_w(fdt, nodeoffset, name, &oldlen);
301 newlen = len + oldlen;
302 err = fdt_splice_struct_(fdt, prop->data,
303 FDT_TAGALIGN(oldlen),
304 FDT_TAGALIGN(newlen));
307 prop->len = cpu_to_fdt32(newlen);
308 memcpy(prop->data + oldlen, val, len);
310 err = fdt_add_property_(fdt, nodeoffset, name, len, &prop);
313 memcpy(prop->data, val, len);
318 int fdt_delprop(void *fdt, int nodeoffset, const char *name)
320 struct fdt_property *prop;
325 prop = fdt_get_property_w(fdt, nodeoffset, name, &len);
329 proplen = sizeof(*prop) + FDT_TAGALIGN(len);
330 return fdt_splice_struct_(fdt, prop, proplen, 0);
333 int fdt_add_subnode_namelen(void *fdt, int parentoffset,
334 const char *name, int namelen)
336 struct fdt_node_header *nh;
337 int offset, nextoffset;
345 offset = fdt_subnode_offset_namelen(fdt, parentoffset, name, namelen);
347 return -FDT_ERR_EXISTS;
348 else if (offset != -FDT_ERR_NOTFOUND)
351 /* Try to place the new node after the parent's properties */
352 fdt_next_tag(fdt, parentoffset, &nextoffset); /* skip the BEGIN_NODE */
355 tag = fdt_next_tag(fdt, offset, &nextoffset);
356 } while ((tag == FDT_PROP) || (tag == FDT_NOP));
358 nh = fdt_offset_ptr_w_(fdt, offset);
359 nodelen = sizeof(*nh) + FDT_TAGALIGN(namelen+1) + FDT_TAGSIZE;
361 err = fdt_splice_struct_(fdt, nh, 0, nodelen);
365 nh->tag = cpu_to_fdt32(FDT_BEGIN_NODE);
366 memset(nh->name, 0, FDT_TAGALIGN(namelen+1));
367 memcpy(nh->name, name, namelen);
368 endtag = (fdt32_t *)((char *)nh + nodelen - FDT_TAGSIZE);
369 *endtag = cpu_to_fdt32(FDT_END_NODE);
374 int fdt_add_subnode(void *fdt, int parentoffset, const char *name)
376 return fdt_add_subnode_namelen(fdt, parentoffset, name, strlen(name));
379 int fdt_del_node(void *fdt, int nodeoffset)
385 endoffset = fdt_node_end_offset_(fdt, nodeoffset);
389 return fdt_splice_struct_(fdt, fdt_offset_ptr_w_(fdt, nodeoffset),
390 endoffset - nodeoffset, 0);
393 static void fdt_packblocks_(const char *old, char *new,
394 int mem_rsv_size, int struct_size)
396 int mem_rsv_off, struct_off, strings_off;
398 mem_rsv_off = FDT_ALIGN(sizeof(struct fdt_header), 8);
399 struct_off = mem_rsv_off + mem_rsv_size;
400 strings_off = struct_off + struct_size;
402 memmove(new + mem_rsv_off, old + fdt_off_mem_rsvmap(old), mem_rsv_size);
403 fdt_set_off_mem_rsvmap(new, mem_rsv_off);
405 memmove(new + struct_off, old + fdt_off_dt_struct(old), struct_size);
406 fdt_set_off_dt_struct(new, struct_off);
407 fdt_set_size_dt_struct(new, struct_size);
409 memmove(new + strings_off, old + fdt_off_dt_strings(old),
410 fdt_size_dt_strings(old));
411 fdt_set_off_dt_strings(new, strings_off);
412 fdt_set_size_dt_strings(new, fdt_size_dt_strings(old));
415 int fdt_open_into(const void *fdt, void *buf, int bufsize)
418 int mem_rsv_size, struct_size;
420 const char *fdtstart = fdt;
421 const char *fdtend = fdtstart + fdt_totalsize(fdt);
426 mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)
427 * sizeof(struct fdt_reserve_entry);
429 if (can_assume(LATEST) || fdt_version(fdt) >= 17) {
430 struct_size = fdt_size_dt_struct(fdt);
431 } else if (fdt_version(fdt) == 16) {
433 while (fdt_next_tag(fdt, struct_size, &struct_size) != FDT_END)
438 return -FDT_ERR_BADVERSION;
441 if (can_assume(LIBFDT_ORDER) ||
442 !fdt_blocks_misordered_(fdt, mem_rsv_size, struct_size)) {
443 /* no further work necessary */
444 err = fdt_move(fdt, buf, bufsize);
447 fdt_set_version(buf, 17);
448 fdt_set_size_dt_struct(buf, struct_size);
449 fdt_set_totalsize(buf, bufsize);
453 /* Need to reorder */
454 newsize = FDT_ALIGN(sizeof(struct fdt_header), 8) + mem_rsv_size
455 + struct_size + fdt_size_dt_strings(fdt);
457 if (bufsize < newsize)
458 return -FDT_ERR_NOSPACE;
460 /* First attempt to build converted tree at beginning of buffer */
462 /* But if that overlaps with the old tree... */
463 if (((tmp + newsize) > fdtstart) && (tmp < fdtend)) {
464 /* Try right after the old tree instead */
465 tmp = (char *)(uintptr_t)fdtend;
466 if ((tmp + newsize) > ((char *)buf + bufsize))
467 return -FDT_ERR_NOSPACE;
470 fdt_packblocks_(fdt, tmp, mem_rsv_size, struct_size);
471 memmove(buf, tmp, newsize);
473 fdt_set_magic(buf, FDT_MAGIC);
474 fdt_set_totalsize(buf, bufsize);
475 fdt_set_version(buf, 17);
476 fdt_set_last_comp_version(buf, 16);
477 fdt_set_boot_cpuid_phys(buf, fdt_boot_cpuid_phys(fdt));
482 int fdt_pack(void *fdt)
488 mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)
489 * sizeof(struct fdt_reserve_entry);
490 fdt_packblocks_(fdt, fdt, mem_rsv_size, fdt_size_dt_struct(fdt));
491 fdt_set_totalsize(fdt, fdt_data_size_(fdt));