dscontrol.c revision 229989
1254225Speter/****************************************************************************** 2254225Speter * 3254225Speter * Module Name: dscontrol - Support for execution control opcodes - 4254225Speter * if/else/while/return 5254225Speter * 6254225Speter *****************************************************************************/ 7254225Speter 8254225Speter/* 9254225Speter * Copyright (C) 2000 - 2012, Intel Corp. 10254225Speter * All rights reserved. 11254225Speter * 12254225Speter * Redistribution and use in source and binary forms, with or without 13254225Speter * modification, are permitted provided that the following conditions 14254225Speter * are met: 15254225Speter * 1. Redistributions of source code must retain the above copyright 16254225Speter * notice, this list of conditions, and the following disclaimer, 17254225Speter * without modification. 18254225Speter * 2. Redistributions in binary form must reproduce at minimum a disclaimer 19254225Speter * substantially similar to the "NO WARRANTY" disclaimer below 20254225Speter * ("Disclaimer") and any redistribution must be conditioned upon 21254225Speter * including a substantially similar Disclaimer requirement for further 22254225Speter * binary redistribution. 23254225Speter * 3. Neither the names of the above-listed copyright holders nor the names 24254225Speter * of any contributors may be used to endorse or promote products derived 25254225Speter * from this software without specific prior written permission. 26254225Speter * 27254225Speter * Alternatively, this software may be distributed under the terms of the 28254225Speter * GNU General Public License ("GPL") version 2 as published by the Free 29254225Speter * Software Foundation. 30254225Speter * 31254225Speter * NO WARRANTY 32254225Speter * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 33254225Speter * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 34254225Speter * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR 35254225Speter * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 36254225Speter * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 37254225Speter * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 38254225Speter * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 39254225Speter * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 40254225Speter * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 41254225Speter * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 42254225Speter * POSSIBILITY OF SUCH DAMAGES. 43254225Speter */ 44254225Speter 45254225Speter#define __DSCONTROL_C__ 46254225Speter 47254225Speter#include <contrib/dev/acpica/include/acpi.h> 48254225Speter#include <contrib/dev/acpica/include/accommon.h> 49254225Speter#include <contrib/dev/acpica/include/amlcode.h> 50254225Speter#include <contrib/dev/acpica/include/acdispat.h> 51254225Speter#include <contrib/dev/acpica/include/acinterp.h> 52254225Speter 53254225Speter#define _COMPONENT ACPI_DISPATCHER 54254225Speter ACPI_MODULE_NAME ("dscontrol") 55254225Speter 56254225Speter 57254225Speter/******************************************************************************* 58254225Speter * 59254225Speter * FUNCTION: AcpiDsExecBeginControlOp 60254225Speter * 61254225Speter * PARAMETERS: WalkList - The list that owns the walk stack 62254225Speter * Op - The control Op 63254225Speter * 64254225Speter * RETURN: Status 65254225Speter * 66254225Speter * DESCRIPTION: Handles all control ops encountered during control method 67254225Speter * execution. 68254225Speter * 69254225Speter ******************************************************************************/ 70254225Speter 71254225SpeterACPI_STATUS 72254225SpeterAcpiDsExecBeginControlOp ( 73254225Speter ACPI_WALK_STATE *WalkState, 74254225Speter ACPI_PARSE_OBJECT *Op) 75254225Speter{ 76254225Speter ACPI_STATUS Status = AE_OK; 77254225Speter ACPI_GENERIC_STATE *ControlState; 78254225Speter 79254225Speter 80254225Speter ACPI_FUNCTION_NAME (DsExecBeginControlOp); 81254225Speter 82254225Speter 83254225Speter ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Op=%p Opcode=%2.2X State=%p\n", 84254225Speter Op, Op->Common.AmlOpcode, WalkState)); 85254225Speter 86254225Speter switch (Op->Common.AmlOpcode) 87254225Speter { 88254225Speter case AML_WHILE_OP: 89254225Speter 90254225Speter /* 91254225Speter * If this is an additional iteration of a while loop, continue. 92254225Speter * There is no need to allocate a new control state. 93254225Speter */ 94254225Speter if (WalkState->ControlState) 95254225Speter { 96254225Speter if (WalkState->ControlState->Control.AmlPredicateStart == 97254225Speter (WalkState->ParserState.Aml - 1)) 98254225Speter { 99254225Speter /* Reset the state to start-of-loop */ 100254225Speter 101254225Speter WalkState->ControlState->Common.State = 102254225Speter ACPI_CONTROL_CONDITIONAL_EXECUTING; 103254225Speter break; 104254225Speter } 105254225Speter } 106254225Speter 107254225Speter /*lint -fallthrough */ 108254225Speter 109254225Speter case AML_IF_OP: 110254225Speter 111254225Speter /* 112254225Speter * IF/WHILE: Create a new control state to manage these 113254225Speter * constructs. We need to manage these as a stack, in order 114254225Speter * to handle nesting. 115254225Speter */ 116254225Speter ControlState = AcpiUtCreateControlState (); 117254225Speter if (!ControlState) 118254225Speter { 119254225Speter Status = AE_NO_MEMORY; 120254225Speter break; 121254225Speter } 122254225Speter /* 123254225Speter * Save a pointer to the predicate for multiple executions 124254225Speter * of a loop 125254225Speter */ 126254225Speter ControlState->Control.AmlPredicateStart = WalkState->ParserState.Aml - 1; 127254225Speter ControlState->Control.PackageEnd = WalkState->ParserState.PkgEnd; 128254225Speter ControlState->Control.Opcode = Op->Common.AmlOpcode; 129254225Speter 130254225Speter 131254225Speter /* Push the control state on this walk's control stack */ 132254225Speter 133254225Speter AcpiUtPushGenericState (&WalkState->ControlState, ControlState); 134254225Speter break; 135254225Speter 136254225Speter case AML_ELSE_OP: 137254225Speter 138254225Speter /* Predicate is in the state object */ 139254225Speter /* If predicate is true, the IF was executed, ignore ELSE part */ 140254225Speter 141254225Speter if (WalkState->LastPredicate) 142254225Speter { 143254225Speter Status = AE_CTRL_TRUE; 144254225Speter } 145254225Speter 146254225Speter break; 147254225Speter 148254225Speter case AML_RETURN_OP: 149254225Speter 150254225Speter break; 151254225Speter 152254225Speter default: 153254225Speter break; 154254225Speter } 155254225Speter 156254225Speter return (Status); 157254225Speter} 158254225Speter 159254225Speter 160254225Speter/******************************************************************************* 161254225Speter * 162254225Speter * FUNCTION: AcpiDsExecEndControlOp 163254225Speter * 164254225Speter * PARAMETERS: WalkList - The list that owns the walk stack 165254225Speter * Op - The control Op 166254225Speter * 167254225Speter * RETURN: Status 168254225Speter * 169254225Speter * DESCRIPTION: Handles all control ops encountered during control method 170254225Speter * execution. 171254225Speter * 172254225Speter ******************************************************************************/ 173254225Speter 174254225SpeterACPI_STATUS 175254225SpeterAcpiDsExecEndControlOp ( 176254225Speter ACPI_WALK_STATE *WalkState, 177 ACPI_PARSE_OBJECT *Op) 178{ 179 ACPI_STATUS Status = AE_OK; 180 ACPI_GENERIC_STATE *ControlState; 181 182 183 ACPI_FUNCTION_NAME (DsExecEndControlOp); 184 185 186 switch (Op->Common.AmlOpcode) 187 { 188 case AML_IF_OP: 189 190 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "[IF_OP] Op=%p\n", Op)); 191 192 /* 193 * Save the result of the predicate in case there is an 194 * ELSE to come 195 */ 196 WalkState->LastPredicate = 197 (BOOLEAN) WalkState->ControlState->Common.Value; 198 199 /* 200 * Pop the control state that was created at the start 201 * of the IF and free it 202 */ 203 ControlState = AcpiUtPopGenericState (&WalkState->ControlState); 204 AcpiUtDeleteGenericState (ControlState); 205 break; 206 207 208 case AML_ELSE_OP: 209 210 break; 211 212 213 case AML_WHILE_OP: 214 215 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "[WHILE_OP] Op=%p\n", Op)); 216 217 ControlState = WalkState->ControlState; 218 if (ControlState->Common.Value) 219 { 220 /* Predicate was true, the body of the loop was just executed */ 221 222 /* 223 * This loop counter mechanism allows the interpreter to escape 224 * possibly infinite loops. This can occur in poorly written AML 225 * when the hardware does not respond within a while loop and the 226 * loop does not implement a timeout. 227 */ 228 ControlState->Control.LoopCount++; 229 if (ControlState->Control.LoopCount > ACPI_MAX_LOOP_ITERATIONS) 230 { 231 Status = AE_AML_INFINITE_LOOP; 232 break; 233 } 234 235 /* 236 * Go back and evaluate the predicate and maybe execute the loop 237 * another time 238 */ 239 Status = AE_CTRL_PENDING; 240 WalkState->AmlLastWhile = ControlState->Control.AmlPredicateStart; 241 break; 242 } 243 244 /* Predicate was false, terminate this while loop */ 245 246 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, 247 "[WHILE_OP] termination! Op=%p\n",Op)); 248 249 /* Pop this control state and free it */ 250 251 ControlState = AcpiUtPopGenericState (&WalkState->ControlState); 252 AcpiUtDeleteGenericState (ControlState); 253 break; 254 255 256 case AML_RETURN_OP: 257 258 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, 259 "[RETURN_OP] Op=%p Arg=%p\n",Op, Op->Common.Value.Arg)); 260 261 /* 262 * One optional operand -- the return value 263 * It can be either an immediate operand or a result that 264 * has been bubbled up the tree 265 */ 266 if (Op->Common.Value.Arg) 267 { 268 /* Since we have a real Return(), delete any implicit return */ 269 270 AcpiDsClearImplicitReturn (WalkState); 271 272 /* Return statement has an immediate operand */ 273 274 Status = AcpiDsCreateOperands (WalkState, Op->Common.Value.Arg); 275 if (ACPI_FAILURE (Status)) 276 { 277 return (Status); 278 } 279 280 /* 281 * If value being returned is a Reference (such as 282 * an arg or local), resolve it now because it may 283 * cease to exist at the end of the method. 284 */ 285 Status = AcpiExResolveToValue (&WalkState->Operands [0], WalkState); 286 if (ACPI_FAILURE (Status)) 287 { 288 return (Status); 289 } 290 291 /* 292 * Get the return value and save as the last result 293 * value. This is the only place where WalkState->ReturnDesc 294 * is set to anything other than zero! 295 */ 296 WalkState->ReturnDesc = WalkState->Operands[0]; 297 } 298 else if (WalkState->ResultCount) 299 { 300 /* Since we have a real Return(), delete any implicit return */ 301 302 AcpiDsClearImplicitReturn (WalkState); 303 304 /* 305 * The return value has come from a previous calculation. 306 * 307 * If value being returned is a Reference (such as 308 * an arg or local), resolve it now because it may 309 * cease to exist at the end of the method. 310 * 311 * Allow references created by the Index operator to return 312 * unchanged. 313 */ 314 if ((ACPI_GET_DESCRIPTOR_TYPE (WalkState->Results->Results.ObjDesc[0]) == ACPI_DESC_TYPE_OPERAND) && 315 ((WalkState->Results->Results.ObjDesc [0])->Common.Type == ACPI_TYPE_LOCAL_REFERENCE) && 316 ((WalkState->Results->Results.ObjDesc [0])->Reference.Class != ACPI_REFCLASS_INDEX)) 317 { 318 Status = AcpiExResolveToValue (&WalkState->Results->Results.ObjDesc [0], WalkState); 319 if (ACPI_FAILURE (Status)) 320 { 321 return (Status); 322 } 323 } 324 325 WalkState->ReturnDesc = WalkState->Results->Results.ObjDesc [0]; 326 } 327 else 328 { 329 /* No return operand */ 330 331 if (WalkState->NumOperands) 332 { 333 AcpiUtRemoveReference (WalkState->Operands [0]); 334 } 335 336 WalkState->Operands [0] = NULL; 337 WalkState->NumOperands = 0; 338 WalkState->ReturnDesc = NULL; 339 } 340 341 342 ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, 343 "Completed RETURN_OP State=%p, RetVal=%p\n", 344 WalkState, WalkState->ReturnDesc)); 345 346 /* End the control method execution right now */ 347 348 Status = AE_CTRL_TERMINATE; 349 break; 350 351 352 case AML_NOOP_OP: 353 354 /* Just do nothing! */ 355 break; 356 357 358 case AML_BREAK_POINT_OP: 359 360 /* 361 * Set the single-step flag. This will cause the debugger (if present) 362 * to break to the console within the AML debugger at the start of the 363 * next AML instruction. 364 */ 365 ACPI_DEBUGGER_EXEC ( 366 AcpiGbl_CmSingleStep = TRUE); 367 ACPI_DEBUGGER_EXEC ( 368 AcpiOsPrintf ("**break** Executed AML BreakPoint opcode\n")); 369 370 /* Call to the OSL in case OS wants a piece of the action */ 371 372 Status = AcpiOsSignal (ACPI_SIGNAL_BREAKPOINT, 373 "Executed AML Breakpoint opcode"); 374 break; 375 376 377 case AML_BREAK_OP: 378 case AML_CONTINUE_OP: /* ACPI 2.0 */ 379 380 381 /* Pop and delete control states until we find a while */ 382 383 while (WalkState->ControlState && 384 (WalkState->ControlState->Control.Opcode != AML_WHILE_OP)) 385 { 386 ControlState = AcpiUtPopGenericState (&WalkState->ControlState); 387 AcpiUtDeleteGenericState (ControlState); 388 } 389 390 /* No while found? */ 391 392 if (!WalkState->ControlState) 393 { 394 return (AE_AML_NO_WHILE); 395 } 396 397 /* Was: WalkState->AmlLastWhile = WalkState->ControlState->Control.AmlPredicateStart; */ 398 399 WalkState->AmlLastWhile = WalkState->ControlState->Control.PackageEnd; 400 401 /* Return status depending on opcode */ 402 403 if (Op->Common.AmlOpcode == AML_BREAK_OP) 404 { 405 Status = AE_CTRL_BREAK; 406 } 407 else 408 { 409 Status = AE_CTRL_CONTINUE; 410 } 411 break; 412 413 414 default: 415 416 ACPI_ERROR ((AE_INFO, "Unknown control opcode=0x%X Op=%p", 417 Op->Common.AmlOpcode, Op)); 418 419 Status = AE_AML_BAD_OPCODE; 420 break; 421 } 422 423 return (Status); 424} 425