xref: /openbmc/u-boot/lib/libfdt/fdt_rw.c (revision 4e3349b6)
1 /*
2  * libfdt - Flat Device Tree manipulation
3  * Copyright (C) 2006 David Gibson, IBM Corporation.
4  *
5  * libfdt is dual licensed: you can use it either under the terms of
6  * the GPL, or the BSD license, at your option.
7  *
8  *  a) This library is free software; you can redistribute it and/or
9  *     modify it under the terms of the GNU General Public License as
10  *     published by the Free Software Foundation; either version 2 of the
11  *     License, or (at your option) any later version.
12  *
13  *     This library is distributed in the hope that it will be useful,
14  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *     GNU General Public License for more details.
17  *
18  *     You should have received a copy of the GNU General Public
19  *     License along with this library; if not, write to the Free
20  *     Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
21  *     MA 02110-1301 USA
22  *
23  * Alternatively,
24  *
25  *  b) Redistribution and use in source and binary forms, with or
26  *     without modification, are permitted provided that the following
27  *     conditions are met:
28  *
29  *     1. Redistributions of source code must retain the above
30  *        copyright notice, this list of conditions and the following
31  *        disclaimer.
32  *     2. Redistributions in binary form must reproduce the above
33  *        copyright notice, this list of conditions and the following
34  *        disclaimer in the documentation and/or other materials
35  *        provided with the distribution.
36  *
37  *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
38  *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
39  *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
40  *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
41  *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
42  *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
43  *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
44  *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
45  *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
46  *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
47  *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
48  *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
49  *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
50  */
51 #include "libfdt_env.h"
52 
53 #ifndef USE_HOSTCC
54 #include <fdt.h>
55 #include <libfdt.h>
56 #else
57 #include "fdt_host.h"
58 #endif
59 
60 #include "libfdt_internal.h"
61 
62 static int _fdt_blocks_misordered(const void *fdt,
63 			      int mem_rsv_size, int struct_size)
64 {
65 	return (fdt_off_mem_rsvmap(fdt) < FDT_ALIGN(sizeof(struct fdt_header), 8))
66 		|| (fdt_off_dt_struct(fdt) <
67 		    (fdt_off_mem_rsvmap(fdt) + mem_rsv_size))
68 		|| (fdt_off_dt_strings(fdt) <
69 		    (fdt_off_dt_struct(fdt) + struct_size))
70 		|| (fdt_totalsize(fdt) <
71 		    (fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt)));
72 }
73 
74 static int _fdt_rw_check_header(void *fdt)
75 {
76 	FDT_CHECK_HEADER(fdt);
77 
78 	if (fdt_version(fdt) < 17)
79 		return -FDT_ERR_BADVERSION;
80 	if (_fdt_blocks_misordered(fdt, sizeof(struct fdt_reserve_entry),
81 				   fdt_size_dt_struct(fdt)))
82 		return -FDT_ERR_BADLAYOUT;
83 	if (fdt_version(fdt) > 17)
84 		fdt_set_version(fdt, 17);
85 
86 	return 0;
87 }
88 
89 #define FDT_RW_CHECK_HEADER(fdt) \
90 	{ \
91 		int err; \
92 		if ((err = _fdt_rw_check_header(fdt)) != 0) \
93 			return err; \
94 	}
95 
96 static inline int _fdt_data_size(void *fdt)
97 {
98 	return fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt);
99 }
100 
101 static int _fdt_splice(void *fdt, void *splicepoint, int oldlen, int newlen)
102 {
103 	char *p = splicepoint;
104 	char *end = (char *)fdt + _fdt_data_size(fdt);
105 
106 	if (((p + oldlen) < p) || ((p + oldlen) > end))
107 		return -FDT_ERR_BADOFFSET;
108 	if ((end - oldlen + newlen) > ((char *)fdt + fdt_totalsize(fdt)))
109 		return -FDT_ERR_NOSPACE;
110 	memmove(p + newlen, p + oldlen, end - p - oldlen);
111 	return 0;
112 }
113 
114 static int _fdt_splice_mem_rsv(void *fdt, struct fdt_reserve_entry *p,
115 			       int oldn, int newn)
116 {
117 	int delta = (newn - oldn) * sizeof(*p);
118 	int err;
119 	err = _fdt_splice(fdt, p, oldn * sizeof(*p), newn * sizeof(*p));
120 	if (err)
121 		return err;
122 	fdt_set_off_dt_struct(fdt, fdt_off_dt_struct(fdt) + delta);
123 	fdt_set_off_dt_strings(fdt, fdt_off_dt_strings(fdt) + delta);
124 	return 0;
125 }
126 
127 static int _fdt_splice_struct(void *fdt, void *p,
128 			      int oldlen, int newlen)
129 {
130 	int delta = newlen - oldlen;
131 	int err;
132 
133 	if ((err = _fdt_splice(fdt, p, oldlen, newlen)))
134 		return err;
135 
136 	fdt_set_size_dt_struct(fdt, fdt_size_dt_struct(fdt) + delta);
137 	fdt_set_off_dt_strings(fdt, fdt_off_dt_strings(fdt) + delta);
138 	return 0;
139 }
140 
141 static int _fdt_splice_string(void *fdt, int newlen)
142 {
143 	void *p = (char *)fdt
144 		+ fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt);
145 	int err;
146 
147 	if ((err = _fdt_splice(fdt, p, 0, newlen)))
148 		return err;
149 
150 	fdt_set_size_dt_strings(fdt, fdt_size_dt_strings(fdt) + newlen);
151 	return 0;
152 }
153 
154 static int _fdt_find_add_string(void *fdt, const char *s)
155 {
156 	char *strtab = (char *)fdt + fdt_off_dt_strings(fdt);
157 	const char *p;
158 	char *new;
159 	int len = strlen(s) + 1;
160 	int err;
161 
162 	p = _fdt_find_string(strtab, fdt_size_dt_strings(fdt), s);
163 	if (p)
164 		/* found it */
165 		return (p - strtab);
166 
167 	new = strtab + fdt_size_dt_strings(fdt);
168 	err = _fdt_splice_string(fdt, len);
169 	if (err)
170 		return err;
171 
172 	memcpy(new, s, len);
173 	return (new - strtab);
174 }
175 
176 int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size)
177 {
178 	struct fdt_reserve_entry *re;
179 	int err;
180 
181 	FDT_RW_CHECK_HEADER(fdt);
182 
183 	re = _fdt_mem_rsv_w(fdt, fdt_num_mem_rsv(fdt));
184 	err = _fdt_splice_mem_rsv(fdt, re, 0, 1);
185 	if (err)
186 		return err;
187 
188 	re->address = cpu_to_fdt64(address);
189 	re->size = cpu_to_fdt64(size);
190 	return 0;
191 }
192 
193 int fdt_del_mem_rsv(void *fdt, int n)
194 {
195 	struct fdt_reserve_entry *re = _fdt_mem_rsv_w(fdt, n);
196 	int err;
197 
198 	FDT_RW_CHECK_HEADER(fdt);
199 
200 	if (n >= fdt_num_mem_rsv(fdt))
201 		return -FDT_ERR_NOTFOUND;
202 
203 	err = _fdt_splice_mem_rsv(fdt, re, 1, 0);
204 	if (err)
205 		return err;
206 	return 0;
207 }
208 
209 static int _fdt_resize_property(void *fdt, int nodeoffset, const char *name,
210 				int len, struct fdt_property **prop)
211 {
212 	int oldlen;
213 	int err;
214 
215 	*prop = fdt_get_property_w(fdt, nodeoffset, name, &oldlen);
216 	if (! (*prop))
217 		return oldlen;
218 
219 	if ((err = _fdt_splice_struct(fdt, (*prop)->data, FDT_TAGALIGN(oldlen),
220 				      FDT_TAGALIGN(len))))
221 		return err;
222 
223 	(*prop)->len = cpu_to_fdt32(len);
224 	return 0;
225 }
226 
227 static int _fdt_add_property(void *fdt, int nodeoffset, const char *name,
228 			     int len, struct fdt_property **prop)
229 {
230 	int proplen;
231 	int nextoffset;
232 	int namestroff;
233 	int err;
234 
235 	if ((nextoffset = _fdt_check_node_offset(fdt, nodeoffset)) < 0)
236 		return nextoffset;
237 
238 	namestroff = _fdt_find_add_string(fdt, name);
239 	if (namestroff < 0)
240 		return namestroff;
241 
242 	*prop = _fdt_offset_ptr_w(fdt, nextoffset);
243 	proplen = sizeof(**prop) + FDT_TAGALIGN(len);
244 
245 	err = _fdt_splice_struct(fdt, *prop, 0, proplen);
246 	if (err)
247 		return err;
248 
249 	(*prop)->tag = cpu_to_fdt32(FDT_PROP);
250 	(*prop)->nameoff = cpu_to_fdt32(namestroff);
251 	(*prop)->len = cpu_to_fdt32(len);
252 	return 0;
253 }
254 
255 int fdt_set_name(void *fdt, int nodeoffset, const char *name)
256 {
257 	char *namep;
258 	int oldlen, newlen;
259 	int err;
260 
261 	FDT_RW_CHECK_HEADER(fdt);
262 
263 	namep = (char *)(uintptr_t)fdt_get_name(fdt, nodeoffset, &oldlen);
264 	if (!namep)
265 		return oldlen;
266 
267 	newlen = strlen(name);
268 
269 	err = _fdt_splice_struct(fdt, namep, FDT_TAGALIGN(oldlen+1),
270 				 FDT_TAGALIGN(newlen+1));
271 	if (err)
272 		return err;
273 
274 	memcpy(namep, name, newlen+1);
275 	return 0;
276 }
277 
278 int fdt_setprop(void *fdt, int nodeoffset, const char *name,
279 		const void *val, int len)
280 {
281 	struct fdt_property *prop;
282 	int err;
283 
284 	FDT_RW_CHECK_HEADER(fdt);
285 
286 	err = _fdt_resize_property(fdt, nodeoffset, name, len, &prop);
287 	if (err == -FDT_ERR_NOTFOUND)
288 		err = _fdt_add_property(fdt, nodeoffset, name, len, &prop);
289 	if (err)
290 		return err;
291 
292 	memcpy(prop->data, val, len);
293 	return 0;
294 }
295 
296 int fdt_delprop(void *fdt, int nodeoffset, const char *name)
297 {
298 	struct fdt_property *prop;
299 	int len, proplen;
300 
301 	FDT_RW_CHECK_HEADER(fdt);
302 
303 	prop = fdt_get_property_w(fdt, nodeoffset, name, &len);
304 	if (! prop)
305 		return len;
306 
307 	proplen = sizeof(*prop) + FDT_TAGALIGN(len);
308 	return _fdt_splice_struct(fdt, prop, proplen, 0);
309 }
310 
311 int fdt_add_subnode_namelen(void *fdt, int parentoffset,
312 			    const char *name, int namelen)
313 {
314 	struct fdt_node_header *nh;
315 	int offset, nextoffset;
316 	int nodelen;
317 	int err;
318 	uint32_t tag;
319 	uint32_t *endtag;
320 
321 	FDT_RW_CHECK_HEADER(fdt);
322 
323 	offset = fdt_subnode_offset_namelen(fdt, parentoffset, name, namelen);
324 	if (offset >= 0)
325 		return -FDT_ERR_EXISTS;
326 	else if (offset != -FDT_ERR_NOTFOUND)
327 		return offset;
328 
329 	/* Try to place the new node after the parent's properties */
330 	fdt_next_tag(fdt, parentoffset, &nextoffset); /* skip the BEGIN_NODE */
331 	do {
332 		offset = nextoffset;
333 		tag = fdt_next_tag(fdt, offset, &nextoffset);
334 	} while ((tag == FDT_PROP) || (tag == FDT_NOP));
335 
336 	nh = _fdt_offset_ptr_w(fdt, offset);
337 	nodelen = sizeof(*nh) + FDT_TAGALIGN(namelen+1) + FDT_TAGSIZE;
338 
339 	err = _fdt_splice_struct(fdt, nh, 0, nodelen);
340 	if (err)
341 		return err;
342 
343 	nh->tag = cpu_to_fdt32(FDT_BEGIN_NODE);
344 	memset(nh->name, 0, FDT_TAGALIGN(namelen+1));
345 	memcpy(nh->name, name, namelen);
346 	endtag = (uint32_t *)((char *)nh + nodelen - FDT_TAGSIZE);
347 	*endtag = cpu_to_fdt32(FDT_END_NODE);
348 
349 	return offset;
350 }
351 
352 int fdt_add_subnode(void *fdt, int parentoffset, const char *name)
353 {
354 	return fdt_add_subnode_namelen(fdt, parentoffset, name, strlen(name));
355 }
356 
357 int fdt_del_node(void *fdt, int nodeoffset)
358 {
359 	int endoffset;
360 
361 	FDT_RW_CHECK_HEADER(fdt);
362 
363 	endoffset = _fdt_node_end_offset(fdt, nodeoffset);
364 	if (endoffset < 0)
365 		return endoffset;
366 
367 	return _fdt_splice_struct(fdt, _fdt_offset_ptr_w(fdt, nodeoffset),
368 				  endoffset - nodeoffset, 0);
369 }
370 
371 static void _fdt_packblocks(const char *old, char *new,
372 			    int mem_rsv_size, int struct_size)
373 {
374 	int mem_rsv_off, struct_off, strings_off;
375 
376 	mem_rsv_off = FDT_ALIGN(sizeof(struct fdt_header), 8);
377 	struct_off = mem_rsv_off + mem_rsv_size;
378 	strings_off = struct_off + struct_size;
379 
380 	memmove(new + mem_rsv_off, old + fdt_off_mem_rsvmap(old), mem_rsv_size);
381 	fdt_set_off_mem_rsvmap(new, mem_rsv_off);
382 
383 	memmove(new + struct_off, old + fdt_off_dt_struct(old), struct_size);
384 	fdt_set_off_dt_struct(new, struct_off);
385 	fdt_set_size_dt_struct(new, struct_size);
386 
387 	memmove(new + strings_off, old + fdt_off_dt_strings(old),
388 		fdt_size_dt_strings(old));
389 	fdt_set_off_dt_strings(new, strings_off);
390 	fdt_set_size_dt_strings(new, fdt_size_dt_strings(old));
391 }
392 
393 int fdt_open_into(const void *fdt, void *buf, int bufsize)
394 {
395 	int err;
396 	int mem_rsv_size, struct_size;
397 	int newsize;
398 	const char *fdtstart = fdt;
399 	const char *fdtend = fdtstart + fdt_totalsize(fdt);
400 	char *tmp;
401 
402 	FDT_CHECK_HEADER(fdt);
403 
404 	mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)
405 		* sizeof(struct fdt_reserve_entry);
406 
407 	if (fdt_version(fdt) >= 17) {
408 		struct_size = fdt_size_dt_struct(fdt);
409 	} else {
410 		struct_size = 0;
411 		while (fdt_next_tag(fdt, struct_size, &struct_size) != FDT_END)
412 			;
413 		if (struct_size < 0)
414 			return struct_size;
415 	}
416 
417 	if (!_fdt_blocks_misordered(fdt, mem_rsv_size, struct_size)) {
418 		/* no further work necessary */
419 		err = fdt_move(fdt, buf, bufsize);
420 		if (err)
421 			return err;
422 		fdt_set_version(buf, 17);
423 		fdt_set_size_dt_struct(buf, struct_size);
424 		fdt_set_totalsize(buf, bufsize);
425 		return 0;
426 	}
427 
428 	/* Need to reorder */
429 	newsize = FDT_ALIGN(sizeof(struct fdt_header), 8) + mem_rsv_size
430 		+ struct_size + fdt_size_dt_strings(fdt);
431 
432 	if (bufsize < newsize)
433 		return -FDT_ERR_NOSPACE;
434 
435 	/* First attempt to build converted tree at beginning of buffer */
436 	tmp = buf;
437 	/* But if that overlaps with the old tree... */
438 	if (((tmp + newsize) > fdtstart) && (tmp < fdtend)) {
439 		/* Try right after the old tree instead */
440 		tmp = (char *)(uintptr_t)fdtend;
441 		if ((tmp + newsize) > ((char *)buf + bufsize))
442 			return -FDT_ERR_NOSPACE;
443 	}
444 
445 	_fdt_packblocks(fdt, tmp, mem_rsv_size, struct_size);
446 	memmove(buf, tmp, newsize);
447 
448 	fdt_set_magic(buf, FDT_MAGIC);
449 	fdt_set_totalsize(buf, bufsize);
450 	fdt_set_version(buf, 17);
451 	fdt_set_last_comp_version(buf, 16);
452 	fdt_set_boot_cpuid_phys(buf, fdt_boot_cpuid_phys(fdt));
453 
454 	return 0;
455 }
456 
457 int fdt_pack(void *fdt)
458 {
459 	int mem_rsv_size;
460 
461 	FDT_RW_CHECK_HEADER(fdt);
462 
463 	mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)
464 		* sizeof(struct fdt_reserve_entry);
465 	_fdt_packblocks(fdt, fdt, mem_rsv_size, fdt_size_dt_struct(fdt));
466 	fdt_set_totalsize(fdt, _fdt_data_size(fdt));
467 
468 	return 0;
469 }
470