1/****************************************************************************** 2 * 3 * Module Name: psargs - Parse AML opcode arguments 4 * 5 *****************************************************************************/ 6 7/* 8 * Copyright (C) 2000 - 2007, R. Byron Moore 9 * All rights reserved. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions, and the following disclaimer, 16 * without modification. 17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 18 * substantially similar to the "NO WARRANTY" disclaimer below 19 * ("Disclaimer") and any redistribution must be conditioned upon 20 * including a substantially similar Disclaimer requirement for further 21 * binary redistribution. 22 * 3. Neither the names of the above-listed copyright holders nor the names 23 * of any contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * Alternatively, this software may be distributed under the terms of the 27 * GNU General Public License ("GPL") version 2 as published by the Free 28 * Software Foundation. 29 * 30 * NO WARRANTY 31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR 34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 41 * POSSIBILITY OF SUCH DAMAGES. 42 */ 43 44#include <acpi/acpi.h> 45#include <acpi/acparser.h> 46#include <acpi/amlcode.h> 47#include <acpi/acnamesp.h> 48#include <acpi/acdispat.h> 49 50#define _COMPONENT ACPI_PARSER 51ACPI_MODULE_NAME("psargs") 52 53/* Local prototypes */ 54static u32 55acpi_ps_get_next_package_length(struct acpi_parse_state *parser_state); 56 57static union acpi_parse_object *acpi_ps_get_next_field(struct acpi_parse_state 58 *parser_state); 59 60/******************************************************************************* 61 * 62 * FUNCTION: acpi_ps_get_next_package_length 63 * 64 * PARAMETERS: parser_state - Current parser state object 65 * 66 * RETURN: Decoded package length. On completion, the AML pointer points 67 * past the length byte or bytes. 68 * 69 * DESCRIPTION: Decode and return a package length field. 70 * Note: Largest package length is 28 bits, from ACPI specification 71 * 72 ******************************************************************************/ 73 74static u32 75acpi_ps_get_next_package_length(struct acpi_parse_state *parser_state) 76{ 77 u8 *aml = parser_state->aml; 78 u32 package_length = 0; 79 acpi_native_uint byte_count; 80 u8 byte_zero_mask = 0x3F; /* Default [0:5] */ 81 82 ACPI_FUNCTION_TRACE(ps_get_next_package_length); 83 84 /* 85 * Byte 0 bits [6:7] contain the number of additional bytes 86 * used to encode the package length, either 0,1,2, or 3 87 */ 88 byte_count = (aml[0] >> 6); 89 parser_state->aml += (byte_count + 1); 90 91 /* Get bytes 3, 2, 1 as needed */ 92 93 while (byte_count) { 94 /* 95 * Final bit positions for the package length bytes: 96 * Byte3->[20:27] 97 * Byte2->[12:19] 98 * Byte1->[04:11] 99 * Byte0->[00:03] 100 */ 101 package_length |= (aml[byte_count] << ((byte_count << 3) - 4)); 102 103 byte_zero_mask = 0x0F; /* Use bits [0:3] of byte 0 */ 104 byte_count--; 105 } 106 107 /* Byte 0 is a special case, either bits [0:3] or [0:5] are used */ 108 109 package_length |= (aml[0] & byte_zero_mask); 110 return_UINT32(package_length); 111} 112 113/******************************************************************************* 114 * 115 * FUNCTION: acpi_ps_get_next_package_end 116 * 117 * PARAMETERS: parser_state - Current parser state object 118 * 119 * RETURN: Pointer to end-of-package +1 120 * 121 * DESCRIPTION: Get next package length and return a pointer past the end of 122 * the package. Consumes the package length field 123 * 124 ******************************************************************************/ 125 126u8 *acpi_ps_get_next_package_end(struct acpi_parse_state *parser_state) 127{ 128 u8 *start = parser_state->aml; 129 u32 package_length; 130 131 ACPI_FUNCTION_TRACE(ps_get_next_package_end); 132 133 /* Function below updates parser_state->Aml */ 134 135 package_length = acpi_ps_get_next_package_length(parser_state); 136 137 return_PTR(start + package_length); /* end of package */ 138} 139 140/******************************************************************************* 141 * 142 * FUNCTION: acpi_ps_get_next_namestring 143 * 144 * PARAMETERS: parser_state - Current parser state object 145 * 146 * RETURN: Pointer to the start of the name string (pointer points into 147 * the AML. 148 * 149 * DESCRIPTION: Get next raw namestring within the AML stream. Handles all name 150 * prefix characters. Set parser state to point past the string. 151 * (Name is consumed from the AML.) 152 * 153 ******************************************************************************/ 154 155char *acpi_ps_get_next_namestring(struct acpi_parse_state *parser_state) 156{ 157 u8 *start = parser_state->aml; 158 u8 *end = parser_state->aml; 159 160 ACPI_FUNCTION_TRACE(ps_get_next_namestring); 161 162 /* Point past any namestring prefix characters (backslash or carat) */ 163 164 while (acpi_ps_is_prefix_char(*end)) { 165 end++; 166 } 167 168 /* Decode the path prefix character */ 169 170 switch (*end) { 171 case 0: 172 173 /* null_name */ 174 175 if (end == start) { 176 start = NULL; 177 } 178 end++; 179 break; 180 181 case AML_DUAL_NAME_PREFIX: 182 183 /* Two name segments */ 184 185 end += 1 + (2 * ACPI_NAME_SIZE); 186 break; 187 188 case AML_MULTI_NAME_PREFIX_OP: 189 190 /* Multiple name segments, 4 chars each, count in next byte */ 191 192 end += 2 + (*(end + 1) * ACPI_NAME_SIZE); 193 break; 194 195 default: 196 197 /* Single name segment */ 198 199 end += ACPI_NAME_SIZE; 200 break; 201 } 202 203 parser_state->aml = end; 204 return_PTR((char *)start); 205} 206 207/******************************************************************************* 208 * 209 * FUNCTION: acpi_ps_get_next_namepath 210 * 211 * PARAMETERS: parser_state - Current parser state object 212 * Arg - Where the namepath will be stored 213 * arg_count - If the namepath points to a control method 214 * the method's argument is returned here. 215 * possible_method_call - Whether the namepath can possibly be the 216 * start of a method call 217 * 218 * RETURN: Status 219 * 220 * DESCRIPTION: Get next name (if method call, return # of required args). 221 * Names are looked up in the internal namespace to determine 222 * if the name represents a control method. If a method 223 * is found, the number of arguments to the method is returned. 224 * This information is critical for parsing to continue correctly. 225 * 226 ******************************************************************************/ 227 228acpi_status 229acpi_ps_get_next_namepath(struct acpi_walk_state *walk_state, 230 struct acpi_parse_state *parser_state, 231 union acpi_parse_object *arg, u8 possible_method_call) 232{ 233 char *path; 234 union acpi_parse_object *name_op; 235 acpi_status status; 236 union acpi_operand_object *method_desc; 237 struct acpi_namespace_node *node; 238 union acpi_generic_state scope_info; 239 240 ACPI_FUNCTION_TRACE(ps_get_next_namepath); 241 242 path = acpi_ps_get_next_namestring(parser_state); 243 acpi_ps_init_op(arg, AML_INT_NAMEPATH_OP); 244 245 /* Null path case is allowed, just exit */ 246 247 if (!path) { 248 arg->common.value.name = path; 249 return_ACPI_STATUS(AE_OK); 250 } 251 252 /* Setup search scope info */ 253 254 scope_info.scope.node = NULL; 255 node = parser_state->start_node; 256 if (node) { 257 scope_info.scope.node = node; 258 } 259 260 /* 261 * Lookup the name in the internal namespace. We don't want to add 262 * anything new to the namespace here, however, so we use MODE_EXECUTE. 263 * Allow searching of the parent tree, but don't open a new scope - 264 * we just want to lookup the object (must be mode EXECUTE to perform 265 * the upsearch) 266 */ 267 status = 268 acpi_ns_lookup(&scope_info, path, ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE, 269 ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE, 270 NULL, &node); 271 272 /* 273 * If this name is a control method invocation, we must 274 * setup the method call 275 */ 276 if (ACPI_SUCCESS(status) && 277 possible_method_call && (node->type == ACPI_TYPE_METHOD)) { 278 279 /* This name is actually a control method invocation */ 280 281 method_desc = acpi_ns_get_attached_object(node); 282 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 283 "Control Method - %p Desc %p Path=%p\n", node, 284 method_desc, path)); 285 286 name_op = acpi_ps_alloc_op(AML_INT_NAMEPATH_OP); 287 if (!name_op) { 288 return_ACPI_STATUS(AE_NO_MEMORY); 289 } 290 291 /* Change Arg into a METHOD CALL and attach name to it */ 292 293 acpi_ps_init_op(arg, AML_INT_METHODCALL_OP); 294 name_op->common.value.name = path; 295 296 /* Point METHODCALL/NAME to the METHOD Node */ 297 298 name_op->common.node = node; 299 acpi_ps_append_arg(arg, name_op); 300 301 if (!method_desc) { 302 ACPI_ERROR((AE_INFO, 303 "Control Method %p has no attached object", 304 node)); 305 return_ACPI_STATUS(AE_AML_INTERNAL); 306 } 307 308 ACPI_DEBUG_PRINT((ACPI_DB_PARSE, 309 "Control Method - %p Args %X\n", 310 node, method_desc->method.param_count)); 311 312 /* Get the number of arguments to expect */ 313 314 walk_state->arg_count = method_desc->method.param_count; 315 return_ACPI_STATUS(AE_OK); 316 } 317 318 /* 319 * Special handling if the name was not found during the lookup - 320 * some not_found cases are allowed 321 */ 322 if (status == AE_NOT_FOUND) { 323 324 /* 1) not_found is ok during load pass 1/2 (allow forward references) */ 325 326 if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) != 327 ACPI_PARSE_EXECUTE) { 328 status = AE_OK; 329 } 330 331 /* 2) not_found during a cond_ref_of(x) is ok by definition */ 332 333 else if (walk_state->op->common.aml_opcode == 334 AML_COND_REF_OF_OP) { 335 status = AE_OK; 336 } 337 338 /* 339 * 3) not_found while building a Package is ok at this point, we 340 * may flag as an error later if slack mode is not enabled. 341 * (Some ASL code depends on allowing this behavior) 342 */ 343 else if ((arg->common.parent) && 344 ((arg->common.parent->common.aml_opcode == 345 AML_PACKAGE_OP) 346 || (arg->common.parent->common.aml_opcode == 347 AML_VAR_PACKAGE_OP))) { 348 status = AE_OK; 349 } 350 } 351 352 /* Final exception check (may have been changed from code above) */ 353 354 if (ACPI_FAILURE(status)) { 355 ACPI_ERROR_NAMESPACE(path, status); 356 357 if ((walk_state->parse_flags & ACPI_PARSE_MODE_MASK) == 358 ACPI_PARSE_EXECUTE) { 359 360 /* Report a control method execution error */ 361 362 status = acpi_ds_method_error(status, walk_state); 363 } 364 } 365 366 /* Save the namepath */ 367 368 arg->common.value.name = path; 369 return_ACPI_STATUS(status); 370} 371 372/******************************************************************************* 373 * 374 * FUNCTION: acpi_ps_get_next_simple_arg 375 * 376 * PARAMETERS: parser_state - Current parser state object 377 * arg_type - The argument type (AML_*_ARG) 378 * Arg - Where the argument is returned 379 * 380 * RETURN: None 381 * 382 * DESCRIPTION: Get the next simple argument (constant, string, or namestring) 383 * 384 ******************************************************************************/ 385 386void 387acpi_ps_get_next_simple_arg(struct acpi_parse_state *parser_state, 388 u32 arg_type, union acpi_parse_object *arg) 389{ 390 u32 length; 391 u16 opcode; 392 u8 *aml = parser_state->aml; 393 394 ACPI_FUNCTION_TRACE_U32(ps_get_next_simple_arg, arg_type); 395 396 switch (arg_type) { 397 case ARGP_BYTEDATA: 398 399 /* Get 1 byte from the AML stream */ 400 401 opcode = AML_BYTE_OP; 402 arg->common.value.integer = (acpi_integer) * aml; 403 length = 1; 404 break; 405 406 case ARGP_WORDDATA: 407 408 /* Get 2 bytes from the AML stream */ 409 410 opcode = AML_WORD_OP; 411 ACPI_MOVE_16_TO_64(&arg->common.value.integer, aml); 412 length = 2; 413 break; 414 415 case ARGP_DWORDDATA: 416 417 /* Get 4 bytes from the AML stream */ 418 419 opcode = AML_DWORD_OP; 420 ACPI_MOVE_32_TO_64(&arg->common.value.integer, aml); 421 length = 4; 422 break; 423 424 case ARGP_QWORDDATA: 425 426 /* Get 8 bytes from the AML stream */ 427 428 opcode = AML_QWORD_OP; 429 ACPI_MOVE_64_TO_64(&arg->common.value.integer, aml); 430 length = 8; 431 break; 432 433 case ARGP_CHARLIST: 434 435 /* Get a pointer to the string, point past the string */ 436 437 opcode = AML_STRING_OP; 438 arg->common.value.string = ACPI_CAST_PTR(char, aml); 439 440 /* Find the null terminator */ 441 442 length = 0; 443 while (aml[length]) { 444 length++; 445 } 446 length++; 447 break; 448 449 case ARGP_NAME: 450 case ARGP_NAMESTRING: 451 452 acpi_ps_init_op(arg, AML_INT_NAMEPATH_OP); 453 arg->common.value.name = 454 acpi_ps_get_next_namestring(parser_state); 455 return_VOID; 456 457 default: 458 459 ACPI_ERROR((AE_INFO, "Invalid ArgType %X", arg_type)); 460 return_VOID; 461 } 462 463 acpi_ps_init_op(arg, opcode); 464 parser_state->aml += length; 465 return_VOID; 466} 467 468/******************************************************************************* 469 * 470 * FUNCTION: acpi_ps_get_next_field 471 * 472 * PARAMETERS: parser_state - Current parser state object 473 * 474 * RETURN: A newly allocated FIELD op 475 * 476 * DESCRIPTION: Get next field (named_field, reserved_field, or access_field) 477 * 478 ******************************************************************************/ 479 480static union acpi_parse_object *acpi_ps_get_next_field(struct acpi_parse_state 481 *parser_state) 482{ 483 u32 aml_offset = (u32) 484 ACPI_PTR_DIFF(parser_state->aml, 485 parser_state->aml_start); 486 union acpi_parse_object *field; 487 u16 opcode; 488 u32 name; 489 490 ACPI_FUNCTION_TRACE(ps_get_next_field); 491 492 /* Determine field type */ 493 494 switch (ACPI_GET8(parser_state->aml)) { 495 default: 496 497 opcode = AML_INT_NAMEDFIELD_OP; 498 break; 499 500 case 0x00: 501 502 opcode = AML_INT_RESERVEDFIELD_OP; 503 parser_state->aml++; 504 break; 505 506 case 0x01: 507 508 opcode = AML_INT_ACCESSFIELD_OP; 509 parser_state->aml++; 510 break; 511 } 512 513 /* Allocate a new field op */ 514 515 field = acpi_ps_alloc_op(opcode); 516 if (!field) { 517 return_PTR(NULL); 518 } 519 520 field->common.aml_offset = aml_offset; 521 522 /* Decode the field type */ 523 524 switch (opcode) { 525 case AML_INT_NAMEDFIELD_OP: 526 527 /* Get the 4-character name */ 528 529 ACPI_MOVE_32_TO_32(&name, parser_state->aml); 530 acpi_ps_set_name(field, name); 531 parser_state->aml += ACPI_NAME_SIZE; 532 533 /* Get the length which is encoded as a package length */ 534 535 field->common.value.size = 536 acpi_ps_get_next_package_length(parser_state); 537 break; 538 539 case AML_INT_RESERVEDFIELD_OP: 540 541 /* Get the length which is encoded as a package length */ 542 543 field->common.value.size = 544 acpi_ps_get_next_package_length(parser_state); 545 break; 546 547 case AML_INT_ACCESSFIELD_OP: 548 549 /* 550 * Get access_type and access_attrib and merge into the field Op 551 * access_type is first operand, access_attribute is second 552 */ 553 field->common.value.integer = 554 (((u32) ACPI_GET8(parser_state->aml) << 8)); 555 parser_state->aml++; 556 field->common.value.integer |= ACPI_GET8(parser_state->aml); 557 parser_state->aml++; 558 break; 559 560 default: 561 562 /* Opcode was set in previous switch */ 563 break; 564 } 565 566 return_PTR(field); 567} 568 569/******************************************************************************* 570 * 571 * FUNCTION: acpi_ps_get_next_arg 572 * 573 * PARAMETERS: walk_state - Current state 574 * parser_state - Current parser state object 575 * arg_type - The argument type (AML_*_ARG) 576 * return_arg - Where the next arg is returned 577 * 578 * RETURN: Status, and an op object containing the next argument. 579 * 580 * DESCRIPTION: Get next argument (including complex list arguments that require 581 * pushing the parser stack) 582 * 583 ******************************************************************************/ 584 585acpi_status 586acpi_ps_get_next_arg(struct acpi_walk_state *walk_state, 587 struct acpi_parse_state *parser_state, 588 u32 arg_type, union acpi_parse_object **return_arg) 589{ 590 union acpi_parse_object *arg = NULL; 591 union acpi_parse_object *prev = NULL; 592 union acpi_parse_object *field; 593 u32 subop; 594 acpi_status status = AE_OK; 595 596 ACPI_FUNCTION_TRACE_PTR(ps_get_next_arg, parser_state); 597 598 switch (arg_type) { 599 case ARGP_BYTEDATA: 600 case ARGP_WORDDATA: 601 case ARGP_DWORDDATA: 602 case ARGP_CHARLIST: 603 case ARGP_NAME: 604 case ARGP_NAMESTRING: 605 606 /* Constants, strings, and namestrings are all the same size */ 607 608 arg = acpi_ps_alloc_op(AML_BYTE_OP); 609 if (!arg) { 610 return_ACPI_STATUS(AE_NO_MEMORY); 611 } 612 acpi_ps_get_next_simple_arg(parser_state, arg_type, arg); 613 break; 614 615 case ARGP_PKGLENGTH: 616 617 /* Package length, nothing returned */ 618 619 parser_state->pkg_end = 620 acpi_ps_get_next_package_end(parser_state); 621 break; 622 623 case ARGP_FIELDLIST: 624 625 if (parser_state->aml < parser_state->pkg_end) { 626 627 /* Non-empty list */ 628 629 while (parser_state->aml < parser_state->pkg_end) { 630 field = acpi_ps_get_next_field(parser_state); 631 if (!field) { 632 return_ACPI_STATUS(AE_NO_MEMORY); 633 } 634 635 if (prev) { 636 prev->common.next = field; 637 } else { 638 arg = field; 639 } 640 prev = field; 641 } 642 643 /* Skip to End of byte data */ 644 645 parser_state->aml = parser_state->pkg_end; 646 } 647 break; 648 649 case ARGP_BYTELIST: 650 651 if (parser_state->aml < parser_state->pkg_end) { 652 653 /* Non-empty list */ 654 655 arg = acpi_ps_alloc_op(AML_INT_BYTELIST_OP); 656 if (!arg) { 657 return_ACPI_STATUS(AE_NO_MEMORY); 658 } 659 660 /* Fill in bytelist data */ 661 662 arg->common.value.size = (u32) 663 ACPI_PTR_DIFF(parser_state->pkg_end, 664 parser_state->aml); 665 arg->named.data = parser_state->aml; 666 667 /* Skip to End of byte data */ 668 669 parser_state->aml = parser_state->pkg_end; 670 } 671 break; 672 673 case ARGP_TARGET: 674 case ARGP_SUPERNAME: 675 case ARGP_SIMPLENAME: 676 677 subop = acpi_ps_peek_opcode(parser_state); 678 if (subop == 0 || 679 acpi_ps_is_leading_char(subop) || 680 acpi_ps_is_prefix_char(subop)) { 681 682 /* null_name or name_string */ 683 684 arg = acpi_ps_alloc_op(AML_INT_NAMEPATH_OP); 685 if (!arg) { 686 return_ACPI_STATUS(AE_NO_MEMORY); 687 } 688 689 status = 690 acpi_ps_get_next_namepath(walk_state, parser_state, 691 arg, 0); 692 } else { 693 /* Single complex argument, nothing returned */ 694 695 walk_state->arg_count = 1; 696 } 697 break; 698 699 case ARGP_DATAOBJ: 700 case ARGP_TERMARG: 701 702 /* Single complex argument, nothing returned */ 703 704 walk_state->arg_count = 1; 705 break; 706 707 case ARGP_DATAOBJLIST: 708 case ARGP_TERMLIST: 709 case ARGP_OBJLIST: 710 711 if (parser_state->aml < parser_state->pkg_end) { 712 713 /* Non-empty list of variable arguments, nothing returned */ 714 715 walk_state->arg_count = ACPI_VAR_ARGS; 716 } 717 break; 718 719 default: 720 721 ACPI_ERROR((AE_INFO, "Invalid ArgType: %X", arg_type)); 722 status = AE_AML_OPERAND_TYPE; 723 break; 724 } 725 726 *return_arg = arg; 727 return_ACPI_STATUS(status); 728} 729