fdtget.c revision 318102
111695Sache/* 211695Sache * Copyright (c) 2011 The Chromium OS Authors. All rights reserved. 311695Sache * 411695Sache * Portions from U-Boot cmd_fdt.c (C) Copyright 2007 511695Sache * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com 611695Sache * Based on code written by: 711695Sache * Pantelis Antoniou <pantelis.antoniou@gmail.com> and 8227753Stheraven * Matthew McClintock <msm@freescale.com> 9227753Stheraven * 10227753Stheraven * This program is free software; you can redistribute it and/or 11227753Stheraven * modify it under the terms of the GNU General Public License as 12227753Stheraven * published by the Free Software Foundation; either version 2 of 1311695Sache * the License, or (at your option) any later version. 1411695Sache * 1511695Sache * This program is distributed in the hope that it will be useful, 1611695Sache * but WITHOUT ANY WARRANTY; without even the implied warranty of 1711695Sache * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 1811695Sache * GNU General Public License for more details. 1911695Sache * 2011695Sache * You should have received a copy of the GNU General Public License 2111695Sache * along with this program; if not, write to the Free Software 2211695Sache * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 2311695Sache * MA 02111-1307 USA 2411695Sache */ 2511695Sache 2611695Sache#include <assert.h> 2711695Sache#include <ctype.h> 2811695Sache#include <getopt.h> 2911695Sache#include <stdio.h> 3011695Sache#include <stdlib.h> 3111695Sache#include <string.h> 3211695Sache 3311695Sache#include <libfdt.h> 3411695Sache 3511695Sache#include "util.h" 3611695Sache 3711695Sacheenum display_mode { 3892986Sobrien MODE_SHOW_VALUE, /* show values for node properties */ 3992986Sobrien MODE_LIST_PROPS, /* list the properties for a node */ 4092986Sobrien MODE_LIST_SUBNODES, /* list the subnodes of a node */ 41232498Stheraven}; 42232498Stheraven 43136609Stjr/* Holds information which controls our output and options */ 4411695Sachestruct display_info { 4511695Sache int type; /* data type (s/i/u/x or 0 for default) */ 4611695Sache int size; /* data size (1/2/4) */ 4711695Sache enum display_mode mode; /* display mode that we are using */ 4811695Sache const char *default_val; /* default value if node/property not found */ 4924694Sache}; 50121845Stjr 51117270Sachestatic void report_error(const char *where, int err) 52129153Stjr{ 5322330Sache fprintf(stderr, "Error at '%s': %s\n", where, fdt_strerror(err)); 5411695Sache} 55232498Stheraven 56232498Stheraven/** 57232498Stheraven * Displays data of a given length according to selected options 58232498Stheraven * 59232498Stheraven * If a specific data type is provided in disp, then this is used. Otherwise 60232498Stheraven * we try to guess the data type / size from the contents. 61232498Stheraven * 62232498Stheraven * @param disp Display information / options 63232498Stheraven * @param data Data to display 64172619Sache * @param len Maximum length of buffer 65172619Sache * @return 0 if ok, -1 if data does not match format 66115626Sache */ 6711695Sachestatic int show_data(struct display_info *disp, const char *data, int len) 68227753Stheraven{ 69117270Sache int i, size; 70227753Stheraven const uint8_t *p = (const uint8_t *)data; 71227753Stheraven const char *s; 72227753Stheraven int value; 73227753Stheraven int is_string; 74227753Stheraven char fmt[3]; 75227753Stheraven 76227753Stheraven /* no data, don't print */ 77227753Stheraven if (len == 0) 78227753Stheraven return 0; 79227753Stheraven 80227753Stheraven is_string = (disp->type) == 's' || 81227753Stheraven (!disp->type && util_is_printable_string(data, len)); 82227753Stheraven if (is_string) { 83227753Stheraven if (data[len - 1] != '\0') { 84227753Stheraven fprintf(stderr, "Unterminated string\n"); 85227753Stheraven return -1; 86232498Stheraven } 87232498Stheraven for (s = data; s - data < len; s += strlen(s) + 1) { 88227753Stheraven if (s != data) 89227753Stheraven printf(" "); 90227753Stheraven printf("%s", (const char *)s); 91227753Stheraven } 92236889Stheraven return 0; 93236889Stheraven } 94236889Stheraven size = disp->size; 95236889Stheraven if (size == -1) { 96236889Stheraven size = (len % 4) == 0 ? 4 : 1; 97236889Stheraven } else if (len % size) { 98236889Stheraven fprintf(stderr, "Property length must be a multiple of " 99236889Stheraven "selected data size\n"); 100236889Stheraven return -1; 101236889Stheraven } 102236889Stheraven fmt[0] = '%'; 103117270Sache fmt[1] = disp->type ? disp->type : 'd'; 104227753Stheraven fmt[2] = '\0'; 105117270Sache for (i = 0; i < len; i += size, p += size) { 10611695Sache if (i) 10711695Sache printf(" "); 10811695Sache value = size == 4 ? fdt32_to_cpu(*(const uint32_t *)p) : 109101498Sache size == 2 ? (*p << 8) | p[1] : *p; 110227753Stheraven printf(fmt, value); 11111695Sache } 11211695Sache return 0; 11311695Sache} 11411695Sache 115101498Sache/** 116236889Stheraven * List all properties in a node, one per line. 117227753Stheraven * 118101263Sache * @param blob FDT blob 11911695Sache * @param node Node to display 12011695Sache * @return 0 if ok, or FDT_ERR... if not. 121117270Sache */ 12220810Sjoergstatic int list_properties(const void *blob, int node) 12320810Sjoerg{ 12420810Sjoerg const struct fdt_property *data; 12520810Sjoerg const char *name; 12611695Sache int prop; 12711695Sache 128101566Sache prop = fdt_first_property_offset(blob, node); 12911695Sache do { 130101498Sache /* Stop silently when there are no more properties */ 131101566Sache if (prop < 0) 132101498Sache return prop == -FDT_ERR_NOTFOUND ? 0 : prop; 133101498Sache data = fdt_get_property_by_offset(blob, prop, NULL); 13411695Sache name = fdt_string(blob, fdt32_to_cpu(data->nameoff)); 135101498Sache if (name) 13611695Sache puts(name); 137227753Stheraven prop = fdt_next_property_offset(blob, prop); 138227753Stheraven } while (1); 139227753Stheraven} 140227753Stheraven 141227753Stheraven#define MAX_LEVEL 32 /* how deeply nested we will go */ 142175586Sache 143136609Stjr/** 144136609Stjr * List all subnodes in a node, one per line 145175586Sache * 146227753Stheraven * @param blob FDT blob 147175586Sache * @param node Node to display 148227753Stheraven * @return 0 if ok, or FDT_ERR... if not. 149175586Sache */ 150227753Stheravenstatic int list_subnodes(const void *blob, int node) 151175586Sache{ 152227753Stheraven int nextoffset; /* next node offset from libfdt */ 153175586Sache uint32_t tag; /* current tag */ 154227753Stheraven int level = 0; /* keep track of nesting level */ 155175586Sache const char *pathp; 156227753Stheraven int depth = 1; /* the assumed depth of this node */ 157175586Sache 158227753Stheraven while (level >= 0) { 159175586Sache tag = fdt_next_tag(blob, node, &nextoffset); 160227753Stheraven switch (tag) { 161175586Sache case FDT_BEGIN_NODE: 162227753Stheraven pathp = fdt_get_name(blob, node, NULL); 163175586Sache if (level <= depth) { 164101498Sache if (pathp == NULL) 165175585Sache pathp = "/* NULL pointer error */"; 166101498Sache if (*pathp == '\0') 167227753Stheraven pathp = "/"; /* root is nameless */ 168236889Stheraven if (level == 1) 169175586Sache puts(pathp); 170227753Stheraven } 171227753Stheraven level++; 172101498Sache if (level >= MAX_LEVEL) { 173175586Sache printf("Nested too deep, aborting.\n"); 174101498Sache return 1; 175101498Sache } 17611695Sache break; 17711695Sache case FDT_END_NODE: 178117270Sache level--; 179117270Sache if (level == 0) 180117270Sache level = -1; /* exit the loop */ 181227753Stheraven break; 182117270Sache case FDT_END: 183117270Sache return 1; 184117270Sache case FDT_PROP: 185117270Sache break; 186117270Sache default: 187227753Stheraven if (level <= depth) 188227753Stheraven printf("Unknown tag 0x%08X\n", tag); 189232498Stheraven return 1; 190117270Sache } 191117270Sache node = nextoffset; 192232498Stheraven } 193232498Stheraven return 0; 194232498Stheraven} 195232498Stheraven 196232498Stheraven/** 197232498Stheraven * Show the data for a given node (and perhaps property) according to the 198232498Stheraven * display option provided. 199232498Stheraven * 200232498Stheraven * @param blob FDT blob 201232498Stheraven * @param disp Display information / options 202232498Stheraven * @param node Node to display 203232498Stheraven * @param property Name of property to display, or NULL if none 204232498Stheraven * @return 0 if ok, -ve on error 205232498Stheraven */ 206232498Stheravenstatic int show_data_for_item(const void *blob, struct display_info *disp, 207227753Stheraven int node, const char *property) 208227753Stheraven{ 209227753Stheraven const void *value = NULL; 210227753Stheraven int len, err = 0; 211227753Stheraven 212227753Stheraven switch (disp->mode) { 213227753Stheraven case MODE_LIST_PROPS: 214227753Stheraven err = list_properties(blob, node); 215227753Stheraven break; 216227753Stheraven 217 case MODE_LIST_SUBNODES: 218 err = list_subnodes(blob, node); 219 break; 220 221 default: 222 assert(property); 223 value = fdt_getprop(blob, node, property, &len); 224 if (value) { 225 if (show_data(disp, value, len)) 226 err = -1; 227 else 228 printf("\n"); 229 } else if (disp->default_val) { 230 puts(disp->default_val); 231 } else { 232 report_error(property, len); 233 err = -1; 234 } 235 break; 236 } 237 238 return err; 239} 240 241/** 242 * Run the main fdtget operation, given a filename and valid arguments 243 * 244 * @param disp Display information / options 245 * @param filename Filename of blob file 246 * @param arg List of arguments to process 247 * @param arg_count Number of arguments 248 * @param return 0 if ok, -ve on error 249 */ 250static int do_fdtget(struct display_info *disp, const char *filename, 251 char **arg, int arg_count, int args_per_step) 252{ 253 char *blob; 254 const char *prop; 255 int i, node; 256 257 blob = utilfdt_read(filename); 258 if (!blob) 259 return -1; 260 261 for (i = 0; i + args_per_step <= arg_count; i += args_per_step) { 262 node = fdt_path_offset(blob, arg[i]); 263 if (node < 0) { 264 if (disp->default_val) { 265 puts(disp->default_val); 266 continue; 267 } else { 268 report_error(arg[i], node); 269 free(blob); 270 return -1; 271 } 272 } 273 prop = args_per_step == 1 ? NULL : arg[i + 1]; 274 275 if (show_data_for_item(blob, disp, node, prop)) { 276 free(blob); 277 return -1; 278 } 279 } 280 281 free(blob); 282 283 return 0; 284} 285 286/* Usage related data. */ 287static const char usage_synopsis[] = 288 "read values from device tree\n" 289 " fdtget <options> <dt file> [<node> <property>]...\n" 290 " fdtget -p <options> <dt file> [<node> ]...\n" 291 "\n" 292 "Each value is printed on a new line.\n" 293 USAGE_TYPE_MSG; 294static const char usage_short_opts[] = "t:pld:" USAGE_COMMON_SHORT_OPTS; 295static struct option const usage_long_opts[] = { 296 {"type", a_argument, NULL, 't'}, 297 {"properties", no_argument, NULL, 'p'}, 298 {"list", no_argument, NULL, 'l'}, 299 {"default", a_argument, NULL, 'd'}, 300 USAGE_COMMON_LONG_OPTS, 301}; 302static const char * const usage_opts_help[] = { 303 "Type of data", 304 "List properties for each node", 305 "List subnodes for each node", 306 "Default value to display when the property is missing", 307 USAGE_COMMON_OPTS_HELP 308}; 309 310int main(int argc, char *argv[]) 311{ 312 int opt; 313 char *filename = NULL; 314 struct display_info disp; 315 int args_per_step = 2; 316 317 /* set defaults */ 318 memset(&disp, '\0', sizeof(disp)); 319 disp.size = -1; 320 disp.mode = MODE_SHOW_VALUE; 321 while ((opt = util_getopt_long()) != EOF) { 322 switch (opt) { 323 case_USAGE_COMMON_FLAGS 324 325 case 't': 326 if (utilfdt_decode_type(optarg, &disp.type, 327 &disp.size)) 328 usage("invalid type string"); 329 break; 330 331 case 'p': 332 disp.mode = MODE_LIST_PROPS; 333 args_per_step = 1; 334 break; 335 336 case 'l': 337 disp.mode = MODE_LIST_SUBNODES; 338 args_per_step = 1; 339 break; 340 341 case 'd': 342 disp.default_val = optarg; 343 break; 344 } 345 } 346 347 if (optind < argc) 348 filename = argv[optind++]; 349 if (!filename) 350 usage("missing filename"); 351 352 argv += optind; 353 argc -= optind; 354 355 /* Allow no arguments, and silently succeed */ 356 if (!argc) 357 return 0; 358 359 /* Check for node, property arguments */ 360 if (args_per_step == 2 && (argc % 2)) 361 usage("must have an even number of arguments"); 362 363 if (do_fdtget(&disp, filename, argv, argc, args_per_step)) 364 return 1; 365 return 0; 366} 367