ofw_fdt.c revision 258805
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 258805 2013-12-01 19:03:20Z nwhitehorn $"); 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, cell_t *); 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 * We use the offset from fdtp to the node as the 'phandle' in OF interface. 115 * 116 * phandle is a u32 value, therefore we cannot use the pointer to node as 117 * phandle in 64 bit. We also do not use the usual fdt offset as phandle, 118 * as it can be 0, and the OF interface has special meaning for phandle 0. 119 */ 120 121static phandle_t 122fdt_offset_phandle(int offset) 123{ 124 if (offset < 0) 125 return (0); 126 return ((phandle_t)offset + fdt_off_dt_struct(fdtp)); 127} 128 129static int 130fdt_phandle_offset(phandle_t p) 131{ 132 int pint = (int)p; 133 int dtoff = fdt_off_dt_struct(fdtp); 134 135 if (pint < dtoff) 136 return (-1); 137 return (pint - dtoff); 138} 139 140/* Return the next sibling of this node or 0. */ 141static phandle_t 142ofw_fdt_peer(ofw_t ofw, phandle_t node) 143{ 144 int depth, offset; 145 146 if (node == 0) { 147 /* Find root node */ 148 offset = fdt_path_offset(fdtp, "/"); 149 150 return (fdt_offset_phandle(offset)); 151 } 152 153 offset = fdt_phandle_offset(node); 154 if (offset < 0) 155 return (0); 156 157 for (depth = 1, offset = fdt_next_node(fdtp, offset, &depth); 158 offset >= 0; 159 offset = fdt_next_node(fdtp, offset, &depth)) { 160 if (depth < 0) 161 return (0); 162 if (depth == 1) 163 return (fdt_offset_phandle(offset)); 164 } 165 166 return (0); 167} 168 169/* Return the first child of this node or 0. */ 170static phandle_t 171ofw_fdt_child(ofw_t ofw, phandle_t node) 172{ 173 int depth, offset; 174 175 offset = fdt_phandle_offset(node); 176 if (offset < 0) 177 return (0); 178 179 for (depth = 0, offset = fdt_next_node(fdtp, offset, &depth); 180 (offset >= 0) && (depth > 0); 181 offset = fdt_next_node(fdtp, offset, &depth)) { 182 if (depth < 0) 183 return (0); 184 if (depth == 1) 185 return (fdt_offset_phandle(offset)); 186 } 187 188 return (0); 189} 190 191/* Return the parent of this node or 0. */ 192static phandle_t 193ofw_fdt_parent(ofw_t ofw, phandle_t node) 194{ 195 int offset, paroffset; 196 197 offset = fdt_phandle_offset(node); 198 if (offset < 0) 199 return (0); 200 201 paroffset = fdt_parent_offset(fdtp, offset); 202 return (fdt_offset_phandle(paroffset)); 203} 204 205/* Return the package handle that corresponds to an instance handle. */ 206static phandle_t 207ofw_fdt_instance_to_package(ofw_t ofw, ihandle_t instance) 208{ 209 210 /* Where real OF uses ihandles in the tree, FDT uses xref phandles */ 211 return (OF_xref_phandle(instance)); 212} 213 214/* Get the length of a property of a package. */ 215static ssize_t 216ofw_fdt_getproplen(ofw_t ofw, phandle_t package, const char *propname) 217{ 218 const struct fdt_property *prop; 219 int offset, len; 220 221 offset = fdt_phandle_offset(package); 222 if (offset < 0) 223 return (-1); 224 225 if (strcmp(propname, "name") == 0) { 226 /* Emulate the 'name' property */ 227 fdt_get_name(fdtp, offset, &len); 228 return (len + 1); 229 } 230 231 len = -1; 232 prop = fdt_get_property(fdtp, offset, propname, &len); 233 234 return (len); 235} 236 237/* Get the value of a property of a package. */ 238static ssize_t 239ofw_fdt_getprop(ofw_t ofw, phandle_t package, const char *propname, void *buf, 240 size_t buflen) 241{ 242 const void *prop; 243 const char *name; 244 int len, offset; 245 246 offset = fdt_phandle_offset(package); 247 if (offset < 0) 248 return (-1); 249 250 if (strcmp(propname, "name") == 0) { 251 /* Emulate the 'name' property */ 252 name = fdt_get_name(fdtp, offset, &len); 253 strncpy(buf, name, buflen); 254 if (len + 1 > buflen) 255 len = buflen; 256 return (len + 1); 257 } 258 259 prop = fdt_getprop(fdtp, offset, propname, &len); 260 if (prop == NULL) 261 return (-1); 262 263 if (len > buflen) 264 len = buflen; 265 bcopy(prop, buf, len); 266 return (len); 267} 268 269/* 270 * Get the next property of a package. Return the actual len of retrieved 271 * prop name. 272 */ 273static int 274ofw_fdt_nextprop(ofw_t ofw, phandle_t package, const char *previous, char *buf, 275 size_t size) 276{ 277 const struct fdt_property *prop; 278 const char *name; 279 int offset; 280 281 offset = fdt_phandle_offset(package); 282 if (offset < 0) 283 return (-1); 284 285 /* Find the first prop in the node */ 286 offset = fdt_first_property_offset(fdtp, offset); 287 if (offset < 0) 288 return (0); /* No properties */ 289 290 if (previous != NULL) { 291 while (offset >= 0) { 292 prop = fdt_get_property_by_offset(fdtp, offset, NULL); 293 if (prop == NULL) 294 return (-1); /* Internal error */ 295 296 offset = fdt_next_property_offset(fdtp, offset); 297 if (offset < 0) 298 return (0); /* No more properties */ 299 300 /* Check if the last one was the one we wanted */ 301 name = fdt_string(fdtp, fdt32_to_cpu(prop->nameoff)); 302 if (strcmp(name, previous) == 0) 303 break; 304 } 305 } 306 307 prop = fdt_get_property_by_offset(fdtp, offset, &offset); 308 if (prop == NULL) 309 return (-1); /* Internal error */ 310 311 strncpy(buf, fdt_string(fdtp, fdt32_to_cpu(prop->nameoff)), size); 312 313 return (strlen(buf)); 314} 315 316/* Set the value of a property of a package. */ 317static int 318ofw_fdt_setprop(ofw_t ofw, phandle_t package, const char *propname, 319 const void *buf, size_t len) 320{ 321 int offset; 322 323 offset = fdt_phandle_offset(package); 324 if (offset < 0) 325 return (-1); 326 327 return (fdt_setprop_inplace(fdtp, offset, propname, buf, len)); 328} 329 330/* Convert a device specifier to a fully qualified pathname. */ 331static ssize_t 332ofw_fdt_canon(ofw_t ofw, const char *device, char *buf, size_t len) 333{ 334 335 return (-1); 336} 337 338/* Return a package handle for the specified device. */ 339static phandle_t 340ofw_fdt_finddevice(ofw_t ofw, const char *device) 341{ 342 int offset; 343 344 offset = fdt_path_offset(fdtp, device); 345 if (offset < 0) 346 return (-1); 347 return (fdt_offset_phandle(offset)); 348} 349 350/* Return the fully qualified pathname corresponding to an instance. */ 351static ssize_t 352ofw_fdt_instance_to_path(ofw_t ofw, ihandle_t instance, char *buf, size_t len) 353{ 354 phandle_t phandle; 355 356 phandle = OF_instance_to_package(instance); 357 if (phandle == -1) 358 return (-1); 359 360 return (OF_package_to_path(phandle, buf, len)); 361} 362 363/* Return the fully qualified pathname corresponding to a package. */ 364static ssize_t 365ofw_fdt_package_to_path(ofw_t ofw, phandle_t package, char *buf, size_t len) 366{ 367 368 return (-1); 369} 370 371static int 372ofw_fdt_fixup(ofw_t ofw) 373{ 374#define FDT_MODEL_LEN 80 375 char model[FDT_MODEL_LEN]; 376 phandle_t root; 377 ssize_t len; 378 int i; 379 380 if ((root = ofw_fdt_finddevice(ofw, "/")) == -1) 381 return (ENODEV); 382 383 if ((len = ofw_fdt_getproplen(ofw, root, "model")) <= 0) 384 return (0); 385 386 bzero(model, FDT_MODEL_LEN); 387 if (ofw_fdt_getprop(ofw, root, "model", model, FDT_MODEL_LEN) <= 0) 388 return (0); 389 390 /* 391 * Search fixup table and call handler if appropriate. 392 */ 393 for (i = 0; fdt_fixup_table[i].model != NULL; i++) { 394 if (strncmp(model, fdt_fixup_table[i].model, 395 FDT_MODEL_LEN) != 0) 396 continue; 397 398 if (fdt_fixup_table[i].handler != NULL) 399 (*fdt_fixup_table[i].handler)(root); 400 } 401 402 return (0); 403} 404 405static int 406ofw_fdt_interpret(ofw_t ofw, const char *cmd, int nret, cell_t *retvals) 407{ 408 int rv; 409 410 /* 411 * Note: FDT does not have the possibility to 'interpret' commands, 412 * but we abuse the interface a bit to use it for doing non-standard 413 * operations on the device tree blob. 414 * 415 * Currently the only supported 'command' is to trigger performing 416 * fixups. 417 */ 418 if (strncmp("perform-fixup", cmd, 13) != 0) 419 return (0); 420 421 rv = ofw_fdt_fixup(ofw); 422 if (nret > 0) 423 retvals[0] = rv; 424 425 return (rv); 426} 427