scripts/dtc/libfdt/fdt_sw.c

   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_sw_check_header(void *fdt)
  59 {
  60         if (fdt_magic(fdt) != FDT_SW_MAGIC)
  61                 return -FDT_ERR_BADMAGIC;
  62         /* FIXME: should check more details about the header state */
  63         return 0;
  64 }
  65
  66 #define FDT_SW_CHECK_HEADER(fdt) \
  67         { \
  68                 int err; \
  69                 if ((err = _fdt_sw_check_header(fdt)) != 0) \
  70                         return err; \
  71         }
  72
  73 static void *_fdt_grab_space(void *fdt, size_t len)
  74 {
  75         int offset = fdt_size_dt_struct(fdt);
  76         int spaceleft;
  77
  78         spaceleft = fdt_totalsize(fdt) - fdt_off_dt_struct(fdt)
  79                 - fdt_size_dt_strings(fdt);
  80
  81         if ((offset + len < offset) || (offset + len > spaceleft))
  82                 return NULL;
  83
  84         fdt_set_size_dt_struct(fdt, offset + len);
  85         return _fdt_offset_ptr_w(fdt, offset);
  86 }
  87
  88 int fdt_create(void *buf, int bufsize)
  89 {
  90         void *fdt = buf;
  91
  92         if (bufsize < sizeof(struct fdt_header))
  93                 return -FDT_ERR_NOSPACE;
  94
  95         memset(buf, 0, bufsize);
  96
  97         fdt_set_magic(fdt, FDT_SW_MAGIC);
  98         fdt_set_version(fdt, FDT_LAST_SUPPORTED_VERSION);
  99         fdt_set_last_comp_version(fdt, FDT_FIRST_SUPPORTED_VERSION);
 100         fdt_set_totalsize(fdt,  bufsize);
 101
 102         fdt_set_off_mem_rsvmap(fdt, FDT_ALIGN(sizeof(struct fdt_header),
 103                                               sizeof(struct fdt_reserve_entry)));
 104         fdt_set_off_dt_struct(fdt, fdt_off_mem_rsvmap(fdt));
 105         fdt_set_off_dt_strings(fdt, bufsize);
 106
 107         return 0;
 108 }
 109
 110 int fdt_resize(void *fdt, void *buf, int bufsize)
 111 {
 112         size_t headsize, tailsize;
 113         char *oldtail, *newtail;
 114
 115         FDT_SW_CHECK_HEADER(fdt);
 116
 117         headsize = fdt_off_dt_struct(fdt);
 118         tailsize = fdt_size_dt_strings(fdt);
 119
 120         if ((headsize + tailsize) > bufsize)
 121                 return -FDT_ERR_NOSPACE;
 122
 123         oldtail = (char *)fdt + fdt_totalsize(fdt) - tailsize;
 124         newtail = (char *)buf + bufsize - tailsize;
 125
 126         /* Two cases to avoid clobbering data if the old and new
 127          * buffers partially overlap */
 128         if (buf <= fdt) {
 129                 memmove(buf, fdt, headsize);
 130                 memmove(newtail, oldtail, tailsize);
 131         } else {
 132                 memmove(newtail, oldtail, tailsize);
 133                 memmove(buf, fdt, headsize);
 134         }
 135
 136         fdt_set_off_dt_strings(buf, bufsize);
 137         fdt_set_totalsize(buf, bufsize);
 138
 139         return 0;
 140 }
 141
 142 int fdt_add_reservemap_entry(void *fdt, uint64_t addr, uint64_t size)
 143 {
 144         struct fdt_reserve_entry *re;
 145         int offset;
 146
 147         FDT_SW_CHECK_HEADER(fdt);
 148
 149         if (fdt_size_dt_struct(fdt))
 150                 return -FDT_ERR_BADSTATE;
 151
 152         offset = fdt_off_dt_struct(fdt);
 153         if ((offset + sizeof(*re)) > fdt_totalsize(fdt))
 154                 return -FDT_ERR_NOSPACE;
 155
 156         re = (struct fdt_reserve_entry *)((char *)fdt + offset);
 157         re->address = cpu_to_fdt64(addr);
 158         re->size = cpu_to_fdt64(size);
 159
 160         fdt_set_off_dt_struct(fdt, offset + sizeof(*re));
 161
 162         return 0;
 163 }
 164
 165 int fdt_finish_reservemap(void *fdt)
 166 {
 167         return fdt_add_reservemap_entry(fdt, 0, 0);
 168 }
 169
 170 int fdt_begin_node(void *fdt, const char *name)
 171 {
 172         struct fdt_node_header *nh;
 173         int namelen = strlen(name) + 1;
 174
 175         FDT_SW_CHECK_HEADER(fdt);
 176
 177         nh = _fdt_grab_space(fdt, sizeof(*nh) + FDT_TAGALIGN(namelen));
 178         if (! nh)
 179                 return -FDT_ERR_NOSPACE;
 180
 181         nh->tag = cpu_to_fdt32(FDT_BEGIN_NODE);
 182         memcpy(nh->name, name, namelen);
 183         return 0;
 184 }
 185
 186 int fdt_end_node(void *fdt)
 187 {
 188         fdt32_t *en;
 189
 190         FDT_SW_CHECK_HEADER(fdt);
 191
 192         en = _fdt_grab_space(fdt, FDT_TAGSIZE);
 193         if (! en)
 194                 return -FDT_ERR_NOSPACE;
 195
 196         *en = cpu_to_fdt32(FDT_END_NODE);
 197         return 0;
 198 }
 199
 200 static int _fdt_find_add_string(void *fdt, const char *s)
 201 {
 202         char *strtab = (char *)fdt + fdt_totalsize(fdt);
 203         const char *p;
 204         int strtabsize = fdt_size_dt_strings(fdt);
 205         int len = strlen(s) + 1;
 206         int struct_top, offset;
 207
 208         p = _fdt_find_string(strtab - strtabsize, strtabsize, s);
 209         if (p)
 210                 return p - strtab;
 211
 212         /* Add it */
 213         offset = -strtabsize - len;
 214         struct_top = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt);
 215         if (fdt_totalsize(fdt) + offset < struct_top)
 216                 return 0; /* no more room :( */
 217
 218         memcpy(strtab + offset, s, len);
 219         fdt_set_size_dt_strings(fdt, strtabsize + len);
 220         return offset;
 221 }
 222
 223 int fdt_property_placeholder(void *fdt, const char *name, int len, void **valp)
 224 {
 225         struct fdt_property *prop;
 226         int nameoff;
 227
 228         FDT_SW_CHECK_HEADER(fdt);
 229
 230         nameoff = _fdt_find_add_string(fdt, name);
 231         if (nameoff == 0)
 232                 return -FDT_ERR_NOSPACE;
 233
 234         prop = _fdt_grab_space(fdt, sizeof(*prop) + FDT_TAGALIGN(len));
 235         if (! prop)
 236                 return -FDT_ERR_NOSPACE;
 237
 238         prop->tag = cpu_to_fdt32(FDT_PROP);
 239         prop->nameoff = cpu_to_fdt32(nameoff);
 240         prop->len = cpu_to_fdt32(len);
 241         *valp = prop->data;
 242         return 0;
 243 }
 244
 245 int fdt_property(void *fdt, const char *name, const void *val, int len)
 246 {
 247         void *ptr;
 248         int ret;
 249
 250         ret = fdt_property_placeholder(fdt, name, len, &ptr);
 251         if (ret)
 252                 return ret;
 253         memcpy(ptr, val, len);
 254         return 0;
 255 }
 256
 257 int fdt_finish(void *fdt)
 258 {
 259         char *p = (char *)fdt;
 260         fdt32_t *end;
 261         int oldstroffset, newstroffset;
 262         uint32_t tag;
 263         int offset, nextoffset;
 264
 265         FDT_SW_CHECK_HEADER(fdt);
 266
 267         /* Add terminator */
 268         end = _fdt_grab_space(fdt, sizeof(*end));
 269         if (! end)
 270                 return -FDT_ERR_NOSPACE;
 271         *end = cpu_to_fdt32(FDT_END);
 272
 273         /* Relocate the string table */
 274         oldstroffset = fdt_totalsize(fdt) - fdt_size_dt_strings(fdt);
 275         newstroffset = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt);
 276         memmove(p + newstroffset, p + oldstroffset, fdt_size_dt_strings(fdt));
 277         fdt_set_off_dt_strings(fdt, newstroffset);
 278
 279         /* Walk the structure, correcting string offsets */
 280         offset = 0;
 281         while ((tag = fdt_next_tag(fdt, offset, &nextoffset)) != FDT_END) {
 282                 if (tag == FDT_PROP) {
 283                         struct fdt_property *prop =
 284                                 _fdt_offset_ptr_w(fdt, offset);
 285                         int nameoff;
 286
 287                         nameoff = fdt32_to_cpu(prop->nameoff);
 288                         nameoff += fdt_size_dt_strings(fdt);
 289                         prop->nameoff = cpu_to_fdt32(nameoff);
 290                 }
 291                 offset = nextoffset;
 292         }
 293         if (nextoffset < 0)
 294                 return nextoffset;
 295
 296         /* Finally, adjust the header */
 297         fdt_set_totalsize(fdt, newstroffset + fdt_size_dt_strings(fdt));
 298         fdt_set_magic(fdt, FDT_MAGIC);
 299         return 0;
 300 }