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1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.02/******************************************************************************3 *4 * Module Name: psloop - Main AML parse loop5 *6 * Copyright (C) 2000 - 2023, Intel Corp.7 *8 *****************************************************************************/9 10/*11 * Parse the AML and build an operation tree as most interpreters, (such as12 * Perl) do. Parsing is done by hand rather than with a YACC generated parser13 * to tightly constrain stack and dynamic memory usage. Parsing is kept14 * flexible and the code fairly compact by parsing based on a list of AML15 * opcode templates in aml_op_info[].16 */17 18#include <acpi/acpi.h>19#include "accommon.h"20#include "acinterp.h"21#include "acparser.h"22#include "acdispat.h"23#include "amlcode.h"24#include "acconvert.h"25#include "acnamesp.h"26 27#define _COMPONENT ACPI_PARSER28ACPI_MODULE_NAME("psloop")29 30/* Local prototypes */31static acpi_status32acpi_ps_get_arguments(struct acpi_walk_state *walk_state,33 u8 * aml_op_start, union acpi_parse_object *op);34 35/*******************************************************************************36 *37 * FUNCTION: acpi_ps_get_arguments38 *39 * PARAMETERS: walk_state - Current state40 * aml_op_start - Op start in AML41 * op - Current Op42 *43 * RETURN: Status44 *45 * DESCRIPTION: Get arguments for passed Op.46 *47 ******************************************************************************/48 49static acpi_status50acpi_ps_get_arguments(struct acpi_walk_state *walk_state,51 u8 * aml_op_start, union acpi_parse_object *op)52{53 acpi_status status = AE_OK;54 union acpi_parse_object *arg = NULL;55 56 ACPI_FUNCTION_TRACE_PTR(ps_get_arguments, walk_state);57 58 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,59 "Get arguments for opcode [%s]\n",60 op->common.aml_op_name));61 62 switch (op->common.aml_opcode) {63 case AML_BYTE_OP: /* AML_BYTEDATA_ARG */64 case AML_WORD_OP: /* AML_WORDDATA_ARG */65 case AML_DWORD_OP: /* AML_DWORDATA_ARG */66 case AML_QWORD_OP: /* AML_QWORDATA_ARG */67 case AML_STRING_OP: /* AML_ASCIICHARLIST_ARG */68 69 /* Fill in constant or string argument directly */70 71 acpi_ps_get_next_simple_arg(&(walk_state->parser_state),72 GET_CURRENT_ARG_TYPE(walk_state->73 arg_types),74 op);75 break;76 77 case AML_INT_NAMEPATH_OP: /* AML_NAMESTRING_ARG */78 79 status = acpi_ps_get_next_namepath(walk_state,80 &(walk_state->parser_state),81 op,82 ACPI_POSSIBLE_METHOD_CALL);83 if (ACPI_FAILURE(status)) {84 return_ACPI_STATUS(status);85 }86 87 walk_state->arg_types = 0;88 break;89 90 default:91 /*92 * Op is not a constant or string, append each argument to the Op93 */94 while (GET_CURRENT_ARG_TYPE(walk_state->arg_types) &&95 !walk_state->arg_count) {96 walk_state->aml = walk_state->parser_state.aml;97 98 switch (op->common.aml_opcode) {99 case AML_METHOD_OP:100 case AML_BUFFER_OP:101 case AML_PACKAGE_OP:102 case AML_VARIABLE_PACKAGE_OP:103 case AML_WHILE_OP:104 105 break;106 107 default:108 109 ASL_CV_CAPTURE_COMMENTS(walk_state);110 break;111 }112 113 status =114 acpi_ps_get_next_arg(walk_state,115 &(walk_state->parser_state),116 GET_CURRENT_ARG_TYPE117 (walk_state->arg_types), &arg);118 if (ACPI_FAILURE(status)) {119 return_ACPI_STATUS(status);120 }121 122 if (arg) {123 acpi_ps_append_arg(op, arg);124 }125 126 INCREMENT_ARG_LIST(walk_state->arg_types);127 }128 129 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,130 "Final argument count: %8.8X pass %u\n",131 walk_state->arg_count,132 walk_state->pass_number));133 134 /* Special processing for certain opcodes */135 136 switch (op->common.aml_opcode) {137 case AML_METHOD_OP:138 /*139 * Skip parsing of control method because we don't have enough140 * info in the first pass to parse it correctly.141 *142 * Save the length and address of the body143 */144 op->named.data = walk_state->parser_state.aml;145 op->named.length = (u32)146 (walk_state->parser_state.pkg_end -147 walk_state->parser_state.aml);148 149 /* Skip body of method */150 151 walk_state->parser_state.aml =152 walk_state->parser_state.pkg_end;153 walk_state->arg_count = 0;154 break;155 156 case AML_BUFFER_OP:157 case AML_PACKAGE_OP:158 case AML_VARIABLE_PACKAGE_OP:159 160 if ((op->common.parent) &&161 (op->common.parent->common.aml_opcode ==162 AML_NAME_OP)163 && (walk_state->pass_number <=164 ACPI_IMODE_LOAD_PASS2)) {165 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,166 "Setup Package/Buffer: Pass %u, AML Ptr: %p\n",167 walk_state->pass_number,168 aml_op_start));169 170 /*171 * Skip parsing of Buffers and Packages because we don't have172 * enough info in the first pass to parse them correctly.173 */174 op->named.data = aml_op_start;175 op->named.length = (u32)176 (walk_state->parser_state.pkg_end -177 aml_op_start);178 179 /* Skip body */180 181 walk_state->parser_state.aml =182 walk_state->parser_state.pkg_end;183 walk_state->arg_count = 0;184 }185 break;186 187 case AML_WHILE_OP:188 189 if (walk_state->control_state) {190 walk_state->control_state->control.package_end =191 walk_state->parser_state.pkg_end;192 }193 break;194 195 default:196 197 /* No action for all other opcodes */198 199 break;200 }201 202 break;203 }204 205 return_ACPI_STATUS(AE_OK);206}207 208/*******************************************************************************209 *210 * FUNCTION: acpi_ps_parse_loop211 *212 * PARAMETERS: walk_state - Current state213 *214 * RETURN: Status215 *216 * DESCRIPTION: Parse AML (pointed to by the current parser state) and return217 * a tree of ops.218 *219 ******************************************************************************/220 221acpi_status acpi_ps_parse_loop(struct acpi_walk_state *walk_state)222{223 acpi_status status = AE_OK;224 union acpi_parse_object *op = NULL; /* current op */225 struct acpi_parse_state *parser_state;226 u8 *aml_op_start = NULL;227 u8 opcode_length;228 229 ACPI_FUNCTION_TRACE_PTR(ps_parse_loop, walk_state);230 231 if (walk_state->descending_callback == NULL) {232 return_ACPI_STATUS(AE_BAD_PARAMETER);233 }234 235 parser_state = &walk_state->parser_state;236 walk_state->arg_types = 0;237 238#ifndef ACPI_CONSTANT_EVAL_ONLY239 240 if (walk_state->walk_type & ACPI_WALK_METHOD_RESTART) {241 242 /* We are restarting a preempted control method */243 244 if (acpi_ps_has_completed_scope(parser_state)) {245 /*246 * We must check if a predicate to an IF or WHILE statement247 * was just completed248 */249 if ((parser_state->scope->parse_scope.op) &&250 ((parser_state->scope->parse_scope.op->common.251 aml_opcode == AML_IF_OP)252 || (parser_state->scope->parse_scope.op->common.253 aml_opcode == AML_WHILE_OP))254 && (walk_state->control_state)255 && (walk_state->control_state->common.state ==256 ACPI_CONTROL_PREDICATE_EXECUTING)) {257 /*258 * A predicate was just completed, get the value of the259 * predicate and branch based on that value260 */261 walk_state->op = NULL;262 status =263 acpi_ds_get_predicate_value(walk_state,264 ACPI_TO_POINTER265 (TRUE));266 if (ACPI_FAILURE(status)267 && !ACPI_CNTL_EXCEPTION(status)) {268 if (status == AE_AML_NO_RETURN_VALUE) {269 ACPI_EXCEPTION((AE_INFO, status,270 "Invoked method did not return a value"));271 }272 273 ACPI_EXCEPTION((AE_INFO, status,274 "GetPredicate Failed"));275 return_ACPI_STATUS(status);276 }277 278 status =279 acpi_ps_next_parse_state(walk_state, op,280 status);281 }282 283 acpi_ps_pop_scope(parser_state, &op,284 &walk_state->arg_types,285 &walk_state->arg_count);286 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,287 "Popped scope, Op=%p\n", op));288 } else if (walk_state->prev_op) {289 290 /* We were in the middle of an op */291 292 op = walk_state->prev_op;293 walk_state->arg_types = walk_state->prev_arg_types;294 }295 }296#endif297 298 /* Iterative parsing loop, while there is more AML to process: */299 300 while ((parser_state->aml < parser_state->aml_end) || (op)) {301 ASL_CV_CAPTURE_COMMENTS(walk_state);302 303 aml_op_start = parser_state->aml;304 if (!op) {305 status =306 acpi_ps_create_op(walk_state, aml_op_start, &op);307 if (ACPI_FAILURE(status)) {308 /*309 * ACPI_PARSE_MODULE_LEVEL means that we are loading a table by310 * executing it as a control method. However, if we encounter311 * an error while loading the table, we need to keep trying to312 * load the table rather than aborting the table load. Set the313 * status to AE_OK to proceed with the table load.314 */315 if ((walk_state->316 parse_flags & ACPI_PARSE_MODULE_LEVEL)317 && ((status == AE_ALREADY_EXISTS)318 || (status == AE_NOT_FOUND))) {319 status = AE_OK;320 }321 if (status == AE_CTRL_PARSE_CONTINUE) {322 continue;323 }324 325 if (status == AE_CTRL_PARSE_PENDING) {326 status = AE_OK;327 }328 329 if (status == AE_CTRL_TERMINATE) {330 return_ACPI_STATUS(status);331 }332 333 status =334 acpi_ps_complete_op(walk_state, &op,335 status);336 if (ACPI_FAILURE(status)) {337 return_ACPI_STATUS(status);338 }339 if (acpi_ns_opens_scope340 (acpi_ps_get_opcode_info341 (walk_state->opcode)->object_type)) {342 /*343 * If the scope/device op fails to parse, skip the body of344 * the scope op because the parse failure indicates that345 * the device may not exist.346 */347 ACPI_INFO(("Skipping parse of AML opcode: %s (0x%4.4X)", acpi_ps_get_opcode_name(walk_state->opcode), walk_state->opcode));348 349 /*350 * Determine the opcode length before skipping the opcode.351 * An opcode can be 1 byte or 2 bytes in length.352 */353 opcode_length = 1;354 if ((walk_state->opcode & 0xFF00) ==355 AML_EXTENDED_OPCODE) {356 opcode_length = 2;357 }358 walk_state->parser_state.aml =359 walk_state->aml + opcode_length;360 361 walk_state->parser_state.aml =362 acpi_ps_get_next_package_end363 (&walk_state->parser_state);364 walk_state->aml =365 walk_state->parser_state.aml;366 }367 368 continue;369 }370 371 acpi_ex_start_trace_opcode(op, walk_state);372 }373 374 /*375 * Start arg_count at zero because we don't know if there are376 * any args yet377 */378 walk_state->arg_count = 0;379 380 switch (op->common.aml_opcode) {381 case AML_BYTE_OP:382 case AML_WORD_OP:383 case AML_DWORD_OP:384 case AML_QWORD_OP:385 386 break;387 388 default:389 390 ASL_CV_CAPTURE_COMMENTS(walk_state);391 break;392 }393 394 /* Are there any arguments that must be processed? */395 396 if (walk_state->arg_types) {397 398 /* Get arguments */399 400 status =401 acpi_ps_get_arguments(walk_state, aml_op_start, op);402 if (ACPI_FAILURE(status)) {403 status =404 acpi_ps_complete_op(walk_state, &op,405 status);406 if (ACPI_FAILURE(status)) {407 return_ACPI_STATUS(status);408 }409 if ((walk_state->control_state) &&410 ((walk_state->control_state->control.411 opcode == AML_IF_OP)412 || (walk_state->control_state->control.413 opcode == AML_WHILE_OP))) {414 /*415 * If the if/while op fails to parse, we will skip parsing416 * the body of the op.417 */418 parser_state->aml =419 walk_state->control_state->control.420 aml_predicate_start + 1;421 parser_state->aml =422 acpi_ps_get_next_package_end423 (parser_state);424 walk_state->aml = parser_state->aml;425 426 ACPI_ERROR((AE_INFO,427 "Skipping While/If block"));428 if (*walk_state->aml == AML_ELSE_OP) {429 ACPI_ERROR((AE_INFO,430 "Skipping Else block"));431 walk_state->parser_state.aml =432 walk_state->aml + 1;433 walk_state->parser_state.aml =434 acpi_ps_get_next_package_end435 (parser_state);436 walk_state->aml =437 parser_state->aml;438 }439 ACPI_FREE(acpi_ut_pop_generic_state440 (&walk_state->control_state));441 }442 op = NULL;443 continue;444 }445 }446 447 /* Check for arguments that need to be processed */448 449 ACPI_DEBUG_PRINT((ACPI_DB_PARSE,450 "Parseloop: argument count: %8.8X\n",451 walk_state->arg_count));452 453 if (walk_state->arg_count) {454 /*455 * There are arguments (complex ones), push Op and456 * prepare for argument457 */458 status = acpi_ps_push_scope(parser_state, op,459 walk_state->arg_types,460 walk_state->arg_count);461 if (ACPI_FAILURE(status)) {462 status =463 acpi_ps_complete_op(walk_state, &op,464 status);465 if (ACPI_FAILURE(status)) {466 return_ACPI_STATUS(status);467 }468 469 continue;470 }471 472 op = NULL;473 continue;474 }475 476 /*477 * All arguments have been processed -- Op is complete,478 * prepare for next479 */480 walk_state->op_info =481 acpi_ps_get_opcode_info(op->common.aml_opcode);482 if (walk_state->op_info->flags & AML_NAMED) {483 if (op->common.aml_opcode == AML_REGION_OP ||484 op->common.aml_opcode == AML_DATA_REGION_OP) {485 /*486 * Skip parsing of control method or opregion body,487 * because we don't have enough info in the first pass488 * to parse them correctly.489 *490 * Completed parsing an op_region declaration, we now491 * know the length.492 */493 op->named.length =494 (u32) (parser_state->aml - op->named.data);495 }496 }497 498 if (walk_state->op_info->flags & AML_CREATE) {499 /*500 * Backup to beginning of create_XXXfield declaration (1 for501 * Opcode)502 *503 * body_length is unknown until we parse the body504 */505 op->named.length =506 (u32) (parser_state->aml - op->named.data);507 }508 509 if (op->common.aml_opcode == AML_BANK_FIELD_OP) {510 /*511 * Backup to beginning of bank_field declaration512 *513 * body_length is unknown until we parse the body514 */515 op->named.length =516 (u32) (parser_state->aml - op->named.data);517 }518 519 /* This op complete, notify the dispatcher */520 521 if (walk_state->ascending_callback != NULL) {522 walk_state->op = op;523 walk_state->opcode = op->common.aml_opcode;524 525 status = walk_state->ascending_callback(walk_state);526 status =527 acpi_ps_next_parse_state(walk_state, op, status);528 if (status == AE_CTRL_PENDING) {529 status = AE_OK;530 } else531 if ((walk_state->532 parse_flags & ACPI_PARSE_MODULE_LEVEL)533 && (ACPI_AML_EXCEPTION(status)534 || status == AE_ALREADY_EXISTS535 || status == AE_NOT_FOUND)) {536 /*537 * ACPI_PARSE_MODULE_LEVEL flag means that we538 * are currently loading a table by executing539 * it as a control method. However, if we540 * encounter an error while loading the table,541 * we need to keep trying to load the table542 * rather than aborting the table load (setting543 * the status to AE_OK continues the table544 * load). If we get a failure at this point, it545 * means that the dispatcher got an error while546 * trying to execute the Op.547 */548 status = AE_OK;549 }550 }551 552 status = acpi_ps_complete_op(walk_state, &op, status);553 if (ACPI_FAILURE(status)) {554 return_ACPI_STATUS(status);555 }556 557 } /* while parser_state->Aml */558 559 status = acpi_ps_complete_final_op(walk_state, op, status);560 return_ACPI_STATUS(status);561}562