ofw_fdt.c revision 208615
1/*- 2 * Copyright (c) 2009-2010 The FreeBSD Foundation 3 * All rights reserved. 4 * 5 * This software was developed by Semihalf under sponsorship from 6 * the FreeBSD Foundation. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30#include <sys/cdefs.h> 31__FBSDID("$FreeBSD: head/sys/dev/ofw/ofw_fdt.c 208615 2010-05-28 10:51:44Z raj $"); 32 33#include <sys/param.h> 34#include <sys/kernel.h> 35#include <sys/malloc.h> 36#include <sys/systm.h> 37 38#include <contrib/libfdt/libfdt.h> 39 40#include <machine/stdarg.h> 41 42#include <dev/fdt/fdt_common.h> 43#include <dev/ofw/ofwvar.h> 44#include <dev/ofw/openfirm.h> 45 46#include "ofw_if.h" 47 48#ifdef DEBUG 49#define debugf(fmt, args...) do { printf("%s(): ", __func__); \ 50 printf(fmt,##args); } while (0) 51#else 52#define debugf(fmt, args...) 53#endif 54 55static int ofw_fdt_init(ofw_t, void *); 56static phandle_t ofw_fdt_peer(ofw_t, phandle_t); 57static phandle_t ofw_fdt_child(ofw_t, phandle_t); 58static phandle_t ofw_fdt_parent(ofw_t, phandle_t); 59static phandle_t ofw_fdt_instance_to_package(ofw_t, ihandle_t); 60static ssize_t ofw_fdt_getproplen(ofw_t, phandle_t, const char *); 61static ssize_t ofw_fdt_getprop(ofw_t, phandle_t, const char *, void *, size_t); 62static int ofw_fdt_nextprop(ofw_t, phandle_t, const char *, char *, size_t); 63static int ofw_fdt_setprop(ofw_t, phandle_t, const char *, const void *, 64 size_t); 65static ssize_t ofw_fdt_canon(ofw_t, const char *, char *, size_t); 66static phandle_t ofw_fdt_finddevice(ofw_t, const char *); 67static ssize_t ofw_fdt_instance_to_path(ofw_t, ihandle_t, char *, size_t); 68static ssize_t ofw_fdt_package_to_path(ofw_t, phandle_t, char *, size_t); 69static int ofw_fdt_interpret(ofw_t, const char *, int, unsigned long *); 70 71static ofw_method_t ofw_fdt_methods[] = { 72 OFWMETHOD(ofw_init, ofw_fdt_init), 73 OFWMETHOD(ofw_peer, ofw_fdt_peer), 74 OFWMETHOD(ofw_child, ofw_fdt_child), 75 OFWMETHOD(ofw_parent, ofw_fdt_parent), 76 OFWMETHOD(ofw_instance_to_package, ofw_fdt_instance_to_package), 77 OFWMETHOD(ofw_getproplen, ofw_fdt_getproplen), 78 OFWMETHOD(ofw_getprop, ofw_fdt_getprop), 79 OFWMETHOD(ofw_nextprop, ofw_fdt_nextprop), 80 OFWMETHOD(ofw_setprop, ofw_fdt_setprop), 81 OFWMETHOD(ofw_canon, ofw_fdt_canon), 82 OFWMETHOD(ofw_finddevice, ofw_fdt_finddevice), 83 OFWMETHOD(ofw_instance_to_path, ofw_fdt_instance_to_path), 84 OFWMETHOD(ofw_package_to_path, ofw_fdt_package_to_path), 85 OFWMETHOD(ofw_interpret, ofw_fdt_interpret), 86 { 0, 0 } 87}; 88 89static ofw_def_t ofw_fdt = { 90 OFW_FDT, 91 ofw_fdt_methods, 92 0 93}; 94OFW_DEF(ofw_fdt); 95 96static void *fdtp = NULL; 97 98static int 99ofw_fdt_init(ofw_t ofw, void *data) 100{ 101 int err; 102 103 /* Check FDT blob integrity */ 104 if ((err = fdt_check_header(data)) != 0) 105 return (err); 106 107 fdtp = data; 108 return (0); 109} 110 111/* 112 * Device tree functions 113 */ 114 115static int 116fdt_phandle_offset(phandle_t p) 117{ 118 const char *dt_struct; 119 int offset; 120 121 dt_struct = (const char *)fdtp + fdt_off_dt_struct(fdtp); 122 123 if (((const char *)p < dt_struct) || 124 (const char *)p > (dt_struct + fdt_size_dt_struct(fdtp))) 125 return (-1); 126 127 offset = (const char *)p - dt_struct; 128 if (offset < 0) 129 return (-1); 130 131 return (offset); 132} 133 134/* Return the next sibling of this node or 0. */ 135static phandle_t 136ofw_fdt_peer(ofw_t ofw, phandle_t node) 137{ 138 phandle_t p; 139 int depth, offset; 140 141 if (node == 0) { 142 /* Find root node */ 143 offset = fdt_path_offset(fdtp, "/"); 144 p = (phandle_t)fdt_offset_ptr(fdtp, offset, sizeof(p)); 145 146 return (p); 147 } 148 149 offset = fdt_phandle_offset(node); 150 if (offset < 0) 151 return (0); 152 153 for (depth = 1, offset = fdt_next_node(fdtp, offset, &depth); 154 offset >= 0; 155 offset = fdt_next_node(fdtp, offset, &depth)) { 156 if (depth < 0) 157 return (0); 158 if (depth == 1) { 159 p = (phandle_t)fdt_offset_ptr(fdtp, offset, sizeof(p)); 160 return (p); 161 } 162 } 163 164 return (0); 165} 166 167/* Return the first child of this node or 0. */ 168static phandle_t 169ofw_fdt_child(ofw_t ofw, phandle_t node) 170{ 171 phandle_t p; 172 int depth, offset; 173 174 offset = fdt_phandle_offset(node); 175 if (offset < 0) 176 return (0); 177 178 for (depth = 0, offset = fdt_next_node(fdtp, offset, &depth); 179 (offset >= 0) && (depth > 0); 180 offset = fdt_next_node(fdtp, offset, &depth)) { 181 if (depth < 0) 182 return (0); 183 if (depth == 1) { 184 p = (phandle_t)fdt_offset_ptr(fdtp, offset, sizeof(p)); 185 return (p); 186 } 187 } 188 189 return (0); 190} 191 192/* Return the parent of this node or 0. */ 193static phandle_t 194ofw_fdt_parent(ofw_t ofw, phandle_t node) 195{ 196 phandle_t p; 197 int offset, paroffset; 198 199 offset = fdt_phandle_offset(node); 200 if (offset < 0) 201 return (0); 202 203 paroffset = fdt_parent_offset(fdtp, offset); 204 p = (phandle_t)fdt_offset_ptr(fdtp, paroffset, sizeof(phandle_t)); 205 return (p); 206} 207 208/* Return the package handle that corresponds to an instance handle. */ 209static phandle_t 210ofw_fdt_instance_to_package(ofw_t ofw, ihandle_t instance) 211{ 212 phandle_t p; 213 int offset; 214 215 /* 216 * Note: FDT does not have the notion of instances, but we somewhat 217 * abuse the semantics and let treat as 'instance' the internal 218 * 'phandle' prop, so that ofw I/F consumers have a uniform way of 219 * translation between internal representation (which appear in some 220 * contexts as property values) and effective phandles. 221 */ 222 offset = fdt_node_offset_by_phandle(fdtp, instance); 223 if (offset < 0) 224 return (0); 225 226 p = (phandle_t)fdt_offset_ptr(fdtp, offset, sizeof(phandle_t)); 227 return (p); 228} 229 230/* Get the length of a property of a package. */ 231static ssize_t 232ofw_fdt_getproplen(ofw_t ofw, phandle_t package, const char *propname) 233{ 234 const struct fdt_property *prop; 235 int offset, len; 236 237 offset = fdt_phandle_offset(package); 238 if (offset < 0) 239 return (0); 240 241 if (strcmp(propname, "name") == 0) { 242 /* Emulate the 'name' property */ 243 fdt_get_name(fdtp, offset, &len); 244 return (len + 1); 245 } 246 247 len = 0; 248 prop = fdt_get_property(fdtp, offset, propname, &len); 249 250 return (len); 251} 252 253/* Get the value of a property of a package. */ 254static ssize_t 255ofw_fdt_getprop(ofw_t ofw, phandle_t package, const char *propname, void *buf, 256 size_t buflen) 257{ 258 const void *prop; 259 const char *name; 260 int len, offset; 261 262 offset = fdt_phandle_offset(package); 263 if (offset < 0) 264 return (0); 265 266 if (strcmp(propname, "name") == 0) { 267 /* Emulate the 'name' property */ 268 name = fdt_get_name(fdtp, offset, &len); 269 strncpy(buf, name, buflen); 270 if (len + 1 > buflen) 271 len = buflen; 272 return (len + 1); 273 } 274 275 prop = fdt_getprop(fdtp, offset, propname, &len); 276 if (prop == NULL) 277 return (0); 278 279 if (len > buflen) 280 len = buflen; 281 bcopy(prop, buf, len); 282 return (len); 283} 284 285static int 286fdt_nextprop(int offset, char *buf, size_t size) 287{ 288 const struct fdt_property *prop; 289 const char *name; 290 uint32_t tag; 291 int nextoffset, depth; 292 293 depth = 0; 294 tag = fdt_next_tag(fdtp, offset, &nextoffset); 295 296 /* Find the next prop */ 297 do { 298 offset = nextoffset; 299 tag = fdt_next_tag(fdtp, offset, &nextoffset); 300 301 if (tag == FDT_BEGIN_NODE) 302 depth++; 303 else if (tag == FDT_END_NODE) 304 depth--; 305 else if ((tag == FDT_PROP) && (depth == 0)) { 306 prop = 307 (const struct fdt_property *)fdt_offset_ptr(fdtp, 308 offset, sizeof(*prop)); 309 name = fdt_string(fdtp, 310 fdt32_to_cpu(prop->nameoff)); 311 strncpy(buf, name, size); 312 return (strlen(name)); 313 } else 314 depth = -1; 315 } while (depth >= 0); 316 317 return (0); 318} 319 320/* 321 * Get the next property of a package. Return the actual len of retrieved 322 * prop name. 323 */ 324static int 325ofw_fdt_nextprop(ofw_t ofw, phandle_t package, const char *previous, char *buf, 326 size_t size) 327{ 328 const struct fdt_property *prop; 329 int offset, rv; 330 331 offset = fdt_phandle_offset(package); 332 if (offset < 0) 333 return (0); 334 335 if (previous == NULL) 336 /* Find the first prop in the node */ 337 return (fdt_nextprop(offset, buf, size)); 338 339 /* 340 * Advance to the previous prop 341 */ 342 prop = fdt_get_property(fdtp, offset, previous, NULL); 343 if (prop == NULL) 344 return (0); 345 346 offset = fdt_phandle_offset((phandle_t)prop); 347 rv = fdt_nextprop(offset, buf, size); 348 return (rv); 349} 350 351/* Set the value of a property of a package. */ 352static int 353ofw_fdt_setprop(ofw_t ofw, phandle_t package, const char *propname, 354 const void *buf, size_t len) 355{ 356 int offset; 357 358 offset = fdt_phandle_offset(package); 359 if (offset < 0) 360 return (-1); 361 362 return (fdt_setprop_inplace(fdtp, offset, propname, buf, len)); 363} 364 365/* Convert a device specifier to a fully qualified pathname. */ 366static ssize_t 367ofw_fdt_canon(ofw_t ofw, const char *device, char *buf, size_t len) 368{ 369 370 return (-1); 371} 372 373/* Return a package handle for the specified device. */ 374static phandle_t 375ofw_fdt_finddevice(ofw_t ofw, const char *device) 376{ 377 phandle_t p; 378 int offset; 379 380 offset = fdt_path_offset(fdtp, device); 381 382 p = (phandle_t)fdt_offset_ptr(fdtp, offset, sizeof(p)); 383 384 return (p); 385} 386 387/* Return the fully qualified pathname corresponding to an instance. */ 388static ssize_t 389ofw_fdt_instance_to_path(ofw_t ofw, ihandle_t instance, char *buf, size_t len) 390{ 391 392 return (-1); 393} 394 395/* Return the fully qualified pathname corresponding to a package. */ 396static ssize_t 397ofw_fdt_package_to_path(ofw_t ofw, phandle_t package, char *buf, size_t len) 398{ 399 400 return (-1); 401} 402 403static int 404ofw_fdt_fixup(ofw_t ofw) 405{ 406#define FDT_MODEL_LEN 80 407 char model[FDT_MODEL_LEN]; 408 phandle_t root; 409 ssize_t len; 410 int i; 411 412 if ((root = ofw_fdt_finddevice(ofw, "/")) == 0) 413 return (ENODEV); 414 415 if ((len = ofw_fdt_getproplen(ofw, root, "model")) <= 0) 416 return (0); 417 418 bzero(model, FDT_MODEL_LEN); 419 if (ofw_fdt_getprop(ofw, root, "model", model, FDT_MODEL_LEN) <= 0) 420 return (0); 421 422 /* 423 * Search fixup table and call handler if appropriate. 424 */ 425 for (i = 0; fdt_fixup_table[i].model != NULL; i++) { 426 if (strncmp(model, fdt_fixup_table[i].model, 427 FDT_MODEL_LEN) != 0) 428 continue; 429 430 if (fdt_fixup_table[i].handler != NULL) 431 (*fdt_fixup_table[i].handler)(root); 432 } 433 434 return (0); 435} 436 437static int 438ofw_fdt_interpret(ofw_t ofw, const char *cmd, int nret, unsigned long *retvals) 439{ 440 int rv; 441 442 /* 443 * Note: FDT does not have the possibility to 'interpret' commands, 444 * but we abuse the interface a bit to use it for doing non-standard 445 * operations on the device tree blob. 446 * 447 * Currently the only supported 'command' is to trigger performing 448 * fixups. 449 */ 450 if (strncmp("perform-fixup", cmd, 13) != 0) 451 return (0); 452 453 rv = ofw_fdt_fixup(ofw); 454 if (nret > 0) 455 retvals[0] = rv; 456 457 return (rv); 458} 459