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 #include <fdt.h>

    54 #include <libfdt.h>

    55 

    56 #include "libfdt_internal.h"

    57 

    58 static int _fdt_blocks_misordered(const void *fdt,

    59 			      int mem_rsv_size, int struct_size)

    60 {

    61 	return (fdt_off_mem_rsvmap(fdt) < FDT_ALIGN(sizeof(struct fdt_header), 8))

    62 		|| (fdt_off_dt_struct(fdt) <

    63 		    (fdt_off_mem_rsvmap(fdt) + mem_rsv_size))

    64 		|| (fdt_off_dt_strings(fdt) <

    65 		    (fdt_off_dt_struct(fdt) + struct_size))

    66 		|| (fdt_totalsize(fdt) <

    67 		    (fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt)));

    68 }

    69 

    70 static int _fdt_rw_check_header(void *fdt)

    71 {

    72 	FDT_CHECK_HEADER(fdt);

    73 

    74 	if (fdt_version(fdt) < 17)

    75 		return -FDT_ERR_BADVERSION;

    76 	if (_fdt_blocks_misordered(fdt, sizeof(struct fdt_reserve_entry),

    77 				   fdt_size_dt_struct(fdt)))

    78 		return -FDT_ERR_BADLAYOUT;

    79 	if (fdt_version(fdt) > 17)

    80 		fdt_set_version(fdt, 17);

    81 

    82 	return 0;

    83 }

    84 

    85 #define FDT_RW_CHECK_HEADER(fdt) \

    86 	{ \

    87 		int err; \

    88 		if ((err = _fdt_rw_check_header(fdt)) != 0) \

    89 			return err; \

    90 	}

    91 

    92 static inline int _fdt_data_size(void *fdt)

    93 {

    94 	return fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt);

    95 }

    96 

    97 static int _fdt_splice(void *fdt, void *splicepoint, int oldlen, int newlen)

    98 {

    99 	char *p = splicepoint;

   100 	char *end = (char *)fdt + _fdt_data_size(fdt);

   101 

   102 	if (((p + oldlen) < p) || ((p + oldlen) > end))

   103 		return -FDT_ERR_BADOFFSET;

   104 	if ((end - oldlen + newlen) > ((char *)fdt + fdt_totalsize(fdt)))

   105 		return -FDT_ERR_NOSPACE;

   106 	memmove(p + newlen, p + oldlen, end - p - oldlen);

   107 	return 0;

   108 }

   109 

   110 static int _fdt_splice_mem_rsv(void *fdt, struct fdt_reserve_entry *p,

   111 			       int oldn, int newn)

   112 {

   113 	int delta = (newn - oldn) * sizeof(*p);

   114 	int err;

   115 	err = _fdt_splice(fdt, p, oldn * sizeof(*p), newn * sizeof(*p));

   116 	if (err)

   117 		return err;

   118 	fdt_set_off_dt_struct(fdt, fdt_off_dt_struct(fdt) + delta);

   119 	fdt_set_off_dt_strings(fdt, fdt_off_dt_strings(fdt) + delta);

   120 	return 0;

   121 }

   122 

   123 static int _fdt_splice_struct(void *fdt, void *p,

   124 			      int oldlen, int newlen)

   125 {

   126 	int delta = newlen - oldlen;

   127 	int err;

   128 

   129 	if ((err = _fdt_splice(fdt, p, oldlen, newlen)))

   130 		return err;

   131 

   132 	fdt_set_size_dt_struct(fdt, fdt_size_dt_struct(fdt) + delta);

   133 	fdt_set_off_dt_strings(fdt, fdt_off_dt_strings(fdt) + delta);

   134 	return 0;

   135 }

   136 

   137 static int _fdt_splice_string(void *fdt, int newlen)

   138 {

   139 	void *p = (char *)fdt

   140 		+ fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt);

   141 	int err;

   142 

   143 	if ((err = _fdt_splice(fdt, p, 0, newlen)))

   144 		return err;

   145 

   146 	fdt_set_size_dt_strings(fdt, fdt_size_dt_strings(fdt) + newlen);

   147 	return 0;

   148 }

   149 

   150 static int _fdt_find_add_string(void *fdt, const char *s)

   151 {

   152 	char *strtab = (char *)fdt + fdt_off_dt_strings(fdt);

   153 	const char *p;

   154 	char *new;

   155 	int len = strlen(s) + 1;

   156 	int err;

   157 

   158 	p = _fdt_find_string(strtab, fdt_size_dt_strings(fdt), s);

   159 	if (p)

   160 		/* found it */

   161 		return (p - strtab);

   162 

   163 	new = strtab + fdt_size_dt_strings(fdt);

   164 	err = _fdt_splice_string(fdt, len);

   165 	if (err)

   166 		return err;

   167 

   168 	memcpy(new, s, len);

   169 	return (new - strtab);

   170 }

   171 

   172 int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size)

   173 {

   174 	struct fdt_reserve_entry *re;

   175 	int err;

   176 

   177 	FDT_RW_CHECK_HEADER(fdt);

   178 

   179 	re = _fdt_mem_rsv_w(fdt, fdt_num_mem_rsv(fdt));

   180 	err = _fdt_splice_mem_rsv(fdt, re, 0, 1);

   181 	if (err)

   182 		return err;

   183 

   184 	re->address = cpu_to_fdt64(address);

   185 	re->size = cpu_to_fdt64(size);

   186 	return 0;

   187 }

   188 

   189 int fdt_del_mem_rsv(void *fdt, int n)

   190 {

   191 	struct fdt_reserve_entry *re = _fdt_mem_rsv_w(fdt, n);

   192 	int err;

   193 

   194 	FDT_RW_CHECK_HEADER(fdt);

   195 

   196 	if (n >= fdt_num_mem_rsv(fdt))

   197 		return -FDT_ERR_NOTFOUND;

   198 

   199 	err = _fdt_splice_mem_rsv(fdt, re, 1, 0);

   200 	if (err)

   201 		return err;

   202 	return 0;

   203 }

   204 

   205 static int _fdt_resize_property(void *fdt, int nodeoffset, const char *name,

   206 				int len, struct fdt_property **prop)

   207 {

   208 	int oldlen;

   209 	int err;

   210 

   211 	*prop = fdt_get_property_w(fdt, nodeoffset, name, &oldlen);

   212 	if (! (*prop))

   213 		return oldlen;

   214 

   215 	if ((err = _fdt_splice_struct(fdt, (*prop)->data, FDT_TAGALIGN(oldlen),

   216 				      FDT_TAGALIGN(len))))

   217 		return err;

   218 

   219 	(*prop)->len = cpu_to_fdt32(len);

   220 	return 0;

   221 }

   222 

   223 static int _fdt_add_property(void *fdt, int nodeoffset, const char *name,

   224 			     int len, struct fdt_property **prop)

   225 {

   226 	int proplen;

   227 	int nextoffset;

   228 	int namestroff;

   229 	int err;

   230 

   231 	if ((nextoffset = _fdt_check_node_offset(fdt, nodeoffset)) < 0)

   232 		return nextoffset;

   233 

   234 	namestroff = _fdt_find_add_string(fdt, name);

   235 	if (namestroff < 0)

   236 		return namestroff;

   237 

   238 	*prop = _fdt_offset_ptr_w(fdt, nextoffset);

   239 	proplen = sizeof(**prop) + FDT_TAGALIGN(len);

   240 

   241 	err = _fdt_splice_struct(fdt, *prop, 0, proplen);

   242 	if (err)

   243 		return err;

   244 

   245 	(*prop)->tag = cpu_to_fdt32(FDT_PROP);

   246 	(*prop)->nameoff = cpu_to_fdt32(namestroff);

   247 	(*prop)->len = cpu_to_fdt32(len);

   248 	return 0;

   249 }

   250 

   251 int fdt_set_name(void *fdt, int nodeoffset, const char *name)

   252 {

   253 	char *namep;

   254 	int oldlen, newlen;

   255 	int err;

   256 

   257 	FDT_RW_CHECK_HEADER(fdt);

   258 

   259 	namep = (char *)(uintptr_t)fdt_get_name(fdt, nodeoffset, &oldlen);

   260 	if (!namep)

   261 		return oldlen;

   262 

   263 	newlen = strlen(name);

   264 

   265 	err = _fdt_splice_struct(fdt, namep, FDT_TAGALIGN(oldlen+1),

   266 				 FDT_TAGALIGN(newlen+1));

   267 	if (err)

   268 		return err;

   269 

   270 	memcpy(namep, name, newlen+1);

   271 	return 0;

   272 }

   273 

   274 int fdt_setprop(void *fdt, int nodeoffset, const char *name,

   275 		const void *val, int len)

   276 {

   277 	struct fdt_property *prop;

   278 	int err;

   279 

   280 	FDT_RW_CHECK_HEADER(fdt);

   281 

   282 	err = _fdt_resize_property(fdt, nodeoffset, name, len, &prop);

   283 	if (err == -FDT_ERR_NOTFOUND)

   284 		err = _fdt_add_property(fdt, nodeoffset, name, len, &prop);

   285 	if (err)

   286 		return err;

   287 

   288 	memcpy(prop->data, val, len);

   289 	return 0;

   290 }

   291 

   292 int fdt_delprop(void *fdt, int nodeoffset, const char *name)

   293 {

   294 	struct fdt_property *prop;

   295 	int len, proplen;

   296 

   297 	FDT_RW_CHECK_HEADER(fdt);

   298 

   299 	prop = fdt_get_property_w(fdt, nodeoffset, name, &len);

   300 	if (! prop)

   301 		return len;

   302 

   303 	proplen = sizeof(*prop) + FDT_TAGALIGN(len);

   304 	return _fdt_splice_struct(fdt, prop, proplen, 0);

   305 }

   306 

   307 int fdt_add_subnode_namelen(void *fdt, int parentoffset,

   308 			    const char *name, int namelen)

   309 {

   310 	struct fdt_node_header *nh;

   311 	int offset, nextoffset;

   312 	int nodelen;

   313 	int err;

   314 	uint32_t tag;

   315 	uint32_t *endtag;

   316 

   317 	FDT_RW_CHECK_HEADER(fdt);

   318 

   319 	offset = fdt_subnode_offset_namelen(fdt, parentoffset, name, namelen);

   320 	if (offset >= 0)

   321 		return -FDT_ERR_EXISTS;

   322 	else if (offset != -FDT_ERR_NOTFOUND)

   323 		return offset;

   324 

   325 	/* Try to place the new node after the parent's properties */

   326 	fdt_next_tag(fdt, parentoffset, &nextoffset); /* skip the BEGIN_NODE */

   327 	do {

   328 		offset = nextoffset;

   329 		tag = fdt_next_tag(fdt, offset, &nextoffset);

   330 	} while ((tag == FDT_PROP) || (tag == FDT_NOP));

   331 

   332 	nh = _fdt_offset_ptr_w(fdt, offset);

   333 	nodelen = sizeof(*nh) + FDT_TAGALIGN(namelen+1) + FDT_TAGSIZE;

   334 

   335 	err = _fdt_splice_struct(fdt, nh, 0, nodelen);

   336 	if (err)

   337 		return err;

   338 

   339 	nh->tag = cpu_to_fdt32(FDT_BEGIN_NODE);

   340 	memset(nh->name, 0, FDT_TAGALIGN(namelen+1));

   341 	memcpy(nh->name, name, namelen);

   342 	endtag = (uint32_t *)((char *)nh + nodelen - FDT_TAGSIZE);

   343 	*endtag = cpu_to_fdt32(FDT_END_NODE);

   344 

   345 	return offset;

   346 }

   347 

   348 int fdt_add_subnode(void *fdt, int parentoffset, const char *name)

   349 {

   350 	return fdt_add_subnode_namelen(fdt, parentoffset, name, strlen(name));

   351 }

   352 

   353 int fdt_del_node(void *fdt, int nodeoffset)

   354 {

   355 	int endoffset;

   356 

   357 	FDT_RW_CHECK_HEADER(fdt);

   358 

   359 	endoffset = _fdt_node_end_offset(fdt, nodeoffset);

   360 	if (endoffset < 0)

   361 		return endoffset;

   362 

   363 	return _fdt_splice_struct(fdt, _fdt_offset_ptr_w(fdt, nodeoffset),

   364 				  endoffset - nodeoffset, 0);

   365 }

   366 

   367 static void _fdt_packblocks(const char *old, char *new,

   368 			    int mem_rsv_size, int struct_size)

   369 {

   370 	int mem_rsv_off, struct_off, strings_off;

   371 

   372 	mem_rsv_off = FDT_ALIGN(sizeof(struct fdt_header), 8);

   373 	struct_off = mem_rsv_off + mem_rsv_size;

   374 	strings_off = struct_off + struct_size;

   375 

   376 	memmove(new + mem_rsv_off, old + fdt_off_mem_rsvmap(old), mem_rsv_size);

   377 	fdt_set_off_mem_rsvmap(new, mem_rsv_off);

   378 

   379 	memmove(new + struct_off, old + fdt_off_dt_struct(old), struct_size);

   380 	fdt_set_off_dt_struct(new, struct_off);

   381 	fdt_set_size_dt_struct(new, struct_size);

   382 

   383 	memmove(new + strings_off, old + fdt_off_dt_strings(old),

   384 		fdt_size_dt_strings(old));

   385 	fdt_set_off_dt_strings(new, strings_off);

   386 	fdt_set_size_dt_strings(new, fdt_size_dt_strings(old));

   387 }

   388 

   389 int fdt_open_into(const void *fdt, void *buf, int bufsize)

   390 {

   391 	int err;

   392 	int mem_rsv_size, struct_size;

   393 	int newsize;

   394 	const char *fdtstart = fdt;

   395 	const char *fdtend = fdtstart + fdt_totalsize(fdt);

   396 	char *tmp;

   397 

   398 	FDT_CHECK_HEADER(fdt);

   399 

   400 	mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)

   401 		* sizeof(struct fdt_reserve_entry);

   402 

   403 	if (fdt_version(fdt) >= 17) {

   404 		struct_size = fdt_size_dt_struct(fdt);

   405 	} else {

   406 		struct_size = 0;

   407 		while (fdt_next_tag(fdt, struct_size, &struct_size) != FDT_END)

   408 			;

   409 	}

   410 

   411 	if (!_fdt_blocks_misordered(fdt, mem_rsv_size, struct_size)) {

   412 		/* no further work necessary */

   413 		err = fdt_move(fdt, buf, bufsize);

   414 		if (err)

   415 			return err;

   416 		fdt_set_version(buf, 17);

   417 		fdt_set_size_dt_struct(buf, struct_size);

   418 		fdt_set_totalsize(buf, bufsize);

   419 		return 0;

   420 	}

   421 

   422 	/* Need to reorder */

   423 	newsize = FDT_ALIGN(sizeof(struct fdt_header), 8) + mem_rsv_size

   424 		+ struct_size + fdt_size_dt_strings(fdt);

   425 

   426 	if (bufsize < newsize)

   427 		return -FDT_ERR_NOSPACE;

   428 

   429 	/* First attempt to build converted tree at beginning of buffer */

   430 	tmp = buf;

   431 	/* But if that overlaps with the old tree... */

   432 	if (((tmp + newsize) > fdtstart) && (tmp < fdtend)) {

   433 		/* Try right after the old tree instead */

   434 		tmp = (char *)(uintptr_t)fdtend;

   435 		if ((tmp + newsize) > ((char *)buf + bufsize))

   436 			return -FDT_ERR_NOSPACE;

   437 	}

   438 

   439 	_fdt_packblocks(fdt, tmp, mem_rsv_size, struct_size);

   440 	memmove(buf, tmp, newsize);

   441 

   442 	fdt_set_magic(buf, FDT_MAGIC);

   443 	fdt_set_totalsize(buf, bufsize);

   444 	fdt_set_version(buf, 17);

   445 	fdt_set_last_comp_version(buf, 16);

   446 	fdt_set_boot_cpuid_phys(buf, fdt_boot_cpuid_phys(fdt));

   447 

   448 	return 0;

   449 }

   450 

   451 int fdt_pack(void *fdt)

   452 {

   453 	int mem_rsv_size;

   454 

   455 	FDT_RW_CHECK_HEADER(fdt);

   456 

   457 	mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)

   458 		* sizeof(struct fdt_reserve_entry);

   459 	_fdt_packblocks(fdt, fdt, mem_rsv_size, fdt_size_dt_struct(fdt));

   460 	fdt_set_totalsize(fdt, _fdt_data_size(fdt));

   461 

   462 	return 0;

   463 }