reactos/drivers/bus/acpi/acpica/dispatcher/dscontrol.c

   1 /******************************************************************************
   2  *
   3  * Module Name: dscontrol - Support for execution control opcodes -
   4  *                          if/else/while/return
   5  *
   6  *****************************************************************************/
   7
   8 /******************************************************************************
   9  *
  10  * 1. Copyright Notice
  11  *
  12  * Some or all of this work - Copyright (c) 1999 - 2011, Intel Corp.
  13  * All rights reserved.
  14  *
  15  * 2. License
  16  *
  17  * 2.1. This is your license from Intel Corp. under its intellectual property
  18  * rights.  You may have additional license terms from the party that provided
  19  * you this software, covering your right to use that party's intellectual
  20  * property rights.
  21  *
  22  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
  23  * copy of the source code appearing in this file ("Covered Code") an
  24  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
  25  * base code distributed originally by Intel ("Original Intel Code") to copy,
  26  * make derivatives, distribute, use and display any portion of the Covered
  27  * Code in any form, with the right to sublicense such rights; and
  28  *
  29  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
  30  * license (with the right to sublicense), under only those claims of Intel
  31  * patents that are infringed by the Original Intel Code, to make, use, sell,
  32  * offer to sell, and import the Covered Code and derivative works thereof
  33  * solely to the minimum extent necessary to exercise the above copyright
  34  * license, and in no event shall the patent license extend to any additions
  35  * to or modifications of the Original Intel Code.  No other license or right
  36  * is granted directly or by implication, estoppel or otherwise;
  37  *
  38  * The above copyright and patent license is granted only if the following
  39  * conditions are met:
  40  *
  41  * 3. Conditions
  42  *
  43  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
  44  * Redistribution of source code of any substantial portion of the Covered
  45  * Code or modification with rights to further distribute source must include
  46  * the above Copyright Notice, the above License, this list of Conditions,
  47  * and the following Disclaimer and Export Compliance provision.  In addition,
  48  * Licensee must cause all Covered Code to which Licensee contributes to
  49  * contain a file documenting the changes Licensee made to create that Covered
  50  * Code and the date of any change.  Licensee must include in that file the
  51  * documentation of any changes made by any predecessor Licensee.  Licensee
  52  * must include a prominent statement that the modification is derived,
  53  * directly or indirectly, from Original Intel Code.
  54  *
  55  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
  56  * Redistribution of source code of any substantial portion of the Covered
  57  * Code or modification without rights to further distribute source must
  58  * include the following Disclaimer and Export Compliance provision in the
  59  * documentation and/or other materials provided with distribution.  In
  60  * addition, Licensee may not authorize further sublicense of source of any
  61  * portion of the Covered Code, and must include terms to the effect that the
  62  * license from Licensee to its licensee is limited to the intellectual
  63  * property embodied in the software Licensee provides to its licensee, and
  64  * not to intellectual property embodied in modifications its licensee may
  65  * make.
  66  *
  67  * 3.3. Redistribution of Executable. Redistribution in executable form of any
  68  * substantial portion of the Covered Code or modification must reproduce the
  69  * above Copyright Notice, and the following Disclaimer and Export Compliance
  70  * provision in the documentation and/or other materials provided with the
  71  * distribution.
  72  *
  73  * 3.4. Intel retains all right, title, and interest in and to the Original
  74  * Intel Code.
  75  *
  76  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
  77  * Intel shall be used in advertising or otherwise to promote the sale, use or
  78  * other dealings in products derived from or relating to the Covered Code
  79  * without prior written authorization from Intel.
  80  *
  81  * 4. Disclaimer and Export Compliance
  82  *
  83  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
  84  * HERE.  ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
  85  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT,  ASSISTANCE,
  86  * INSTALLATION, TRAINING OR OTHER SERVICES.  INTEL WILL NOT PROVIDE ANY
  87  * UPDATES, ENHANCEMENTS OR EXTENSIONS.  INTEL SPECIFICALLY DISCLAIMS ANY
  88  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
  89  * PARTICULAR PURPOSE.
  90  *
  91  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
  92  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
  93  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
  94  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
  95  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
  96  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES.  THESE LIMITATIONS
  97  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
  98  * LIMITED REMEDY.
  99  *
 100  * 4.3. Licensee shall not export, either directly or indirectly, any of this
 101  * software or system incorporating such software without first obtaining any
 102  * required license or other approval from the U. S. Department of Commerce or
 103  * any other agency or department of the United States Government.  In the
 104  * event Licensee exports any such software from the United States or
 105  * re-exports any such software from a foreign destination, Licensee shall
 106  * ensure that the distribution and export/re-export of the software is in
 107  * compliance with all laws, regulations, orders, or other restrictions of the
 108  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
 109  * any of its subsidiaries will export/re-export any technical data, process,
 110  * software, or service, directly or indirectly, to any country for which the
 111  * United States government or any agency thereof requires an export license,
 112  * other governmental approval, or letter of assurance, without first obtaining
 113  * such license, approval or letter.
 114  *
 115  *****************************************************************************/
 116
 117 #define __DSCONTROL_C__
 118
 119 #include "acpi.h"
 120 #include "accommon.h"
 121 #include "amlcode.h"
 122 #include "acdispat.h"
 123 #include "acinterp.h"
 124
 125 #define _COMPONENT          ACPI_DISPATCHER
 126         ACPI_MODULE_NAME    ("dscontrol")
 127
 128
 129 /*******************************************************************************
 130  *
 131  * FUNCTION:    AcpiDsExecBeginControlOp
 132  *
 133  * PARAMETERS:  WalkList        - The list that owns the walk stack
 134  *              Op              - The control Op
 135  *
 136  * RETURN:      Status
 137  *
 138  * DESCRIPTION: Handles all control ops encountered during control method
 139  *              execution.
 140  *
 141  ******************************************************************************/
 142
 143 ACPI_STATUS
 144 AcpiDsExecBeginControlOp (
 145     ACPI_WALK_STATE         *WalkState,
 146     ACPI_PARSE_OBJECT       *Op)
 147 {
 148     ACPI_STATUS             Status = AE_OK;
 149     ACPI_GENERIC_STATE      *ControlState;
 150
 151
 152     ACPI_FUNCTION_NAME (DsExecBeginControlOp);
 153
 154
 155     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Op=%p Opcode=%2.2X State=%p\n",
 156         Op, Op->Common.AmlOpcode, WalkState));
 157
 158     switch (Op->Common.AmlOpcode)
 159     {
 160     case AML_WHILE_OP:
 161
 162         /*
 163          * If this is an additional iteration of a while loop, continue.
 164          * There is no need to allocate a new control state.
 165          */
 166         if (WalkState->ControlState)
 167         {
 168             if (WalkState->ControlState->Control.AmlPredicateStart ==
 169                 (WalkState->ParserState.Aml - 1))
 170             {
 171                 /* Reset the state to start-of-loop */
 172
 173                 WalkState->ControlState->Common.State =
 174                     ACPI_CONTROL_CONDITIONAL_EXECUTING;
 175                 break;
 176             }
 177         }
 178
 179         /*lint -fallthrough */
 180
 181     case AML_IF_OP:
 182
 183         /*
 184          * IF/WHILE: Create a new control state to manage these
 185          * constructs. We need to manage these as a stack, in order
 186          * to handle nesting.
 187          */
 188         ControlState = AcpiUtCreateControlState ();
 189         if (!ControlState)
 190         {
 191             Status = AE_NO_MEMORY;
 192             break;
 193         }
 194         /*
 195          * Save a pointer to the predicate for multiple executions
 196          * of a loop
 197          */
 198         ControlState->Control.AmlPredicateStart = WalkState->ParserState.Aml - 1;
 199         ControlState->Control.PackageEnd = WalkState->ParserState.PkgEnd;
 200         ControlState->Control.Opcode = Op->Common.AmlOpcode;
 201
 202
 203         /* Push the control state on this walk's control stack */
 204
 205         AcpiUtPushGenericState (&WalkState->ControlState, ControlState);
 206         break;
 207
 208     case AML_ELSE_OP:
 209
 210         /* Predicate is in the state object */
 211         /* If predicate is true, the IF was executed, ignore ELSE part */
 212
 213         if (WalkState->LastPredicate)
 214         {
 215             Status = AE_CTRL_TRUE;
 216         }
 217
 218         break;
 219
 220     case AML_RETURN_OP:
 221
 222         break;
 223
 224     default:
 225         break;
 226     }
 227
 228     return (Status);
 229 }
 230
 231
 232 /*******************************************************************************
 233  *
 234  * FUNCTION:    AcpiDsExecEndControlOp
 235  *
 236  * PARAMETERS:  WalkList        - The list that owns the walk stack
 237  *              Op              - The control Op
 238  *
 239  * RETURN:      Status
 240  *
 241  * DESCRIPTION: Handles all control ops encountered during control method
 242  *              execution.
 243  *
 244  ******************************************************************************/
 245
 246 ACPI_STATUS
 247 AcpiDsExecEndControlOp (
 248     ACPI_WALK_STATE         *WalkState,
 249     ACPI_PARSE_OBJECT       *Op)
 250 {
 251     ACPI_STATUS             Status = AE_OK;
 252     ACPI_GENERIC_STATE      *ControlState;
 253
 254
 255     ACPI_FUNCTION_NAME (DsExecEndControlOp);
 256
 257
 258     switch (Op->Common.AmlOpcode)
 259     {
 260     case AML_IF_OP:
 261
 262         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "[IF_OP] Op=%p\n", Op));
 263
 264         /*
 265          * Save the result of the predicate in case there is an
 266          * ELSE to come
 267          */
 268         WalkState->LastPredicate =
 269             (BOOLEAN) WalkState->ControlState->Common.Value;
 270
 271         /*
 272          * Pop the control state that was created at the start
 273          * of the IF and free it
 274          */
 275         ControlState = AcpiUtPopGenericState (&WalkState->ControlState);
 276         AcpiUtDeleteGenericState (ControlState);
 277         break;
 278
 279
 280     case AML_ELSE_OP:
 281
 282         break;
 283
 284
 285     case AML_WHILE_OP:
 286
 287         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "[WHILE_OP] Op=%p\n", Op));
 288
 289         ControlState = WalkState->ControlState;
 290         if (ControlState->Common.Value)
 291         {
 292             /* Predicate was true, the body of the loop was just executed */
 293
 294             /*
 295              * This loop counter mechanism allows the interpreter to escape
 296              * possibly infinite loops. This can occur in poorly written AML
 297              * when the hardware does not respond within a while loop and the
 298              * loop does not implement a timeout.
 299              */
 300             ControlState->Control.LoopCount++;
 301             if (ControlState->Control.LoopCount > ACPI_MAX_LOOP_ITERATIONS)
 302             {
 303                 Status = AE_AML_INFINITE_LOOP;
 304                 break;
 305             }
 306
 307             /*
 308              * Go back and evaluate the predicate and maybe execute the loop
 309              * another time
 310              */
 311             Status = AE_CTRL_PENDING;
 312             WalkState->AmlLastWhile = ControlState->Control.AmlPredicateStart;
 313             break;
 314         }
 315
 316         /* Predicate was false, terminate this while loop */
 317
 318         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
 319             "[WHILE_OP] termination! Op=%p\n",Op));
 320
 321         /* Pop this control state and free it */
 322
 323         ControlState = AcpiUtPopGenericState (&WalkState->ControlState);
 324         AcpiUtDeleteGenericState (ControlState);
 325         break;
 326
 327
 328     case AML_RETURN_OP:
 329
 330         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
 331             "[RETURN_OP] Op=%p Arg=%p\n",Op, Op->Common.Value.Arg));
 332
 333         /*
 334          * One optional operand -- the return value
 335          * It can be either an immediate operand or a result that
 336          * has been bubbled up the tree
 337          */
 338         if (Op->Common.Value.Arg)
 339         {
 340             /* Since we have a real Return(), delete any implicit return */
 341
 342             AcpiDsClearImplicitReturn (WalkState);
 343
 344             /* Return statement has an immediate operand */
 345
 346             Status = AcpiDsCreateOperands (WalkState, Op->Common.Value.Arg);
 347             if (ACPI_FAILURE (Status))
 348             {
 349                 return (Status);
 350             }
 351
 352             /*
 353              * If value being returned is a Reference (such as
 354              * an arg or local), resolve it now because it may
 355              * cease to exist at the end of the method.
 356              */
 357             Status = AcpiExResolveToValue (&WalkState->Operands [0], WalkState);
 358             if (ACPI_FAILURE (Status))
 359             {
 360                 return (Status);
 361             }
 362
 363             /*
 364              * Get the return value and save as the last result
 365              * value.  This is the only place where WalkState->ReturnDesc
 366              * is set to anything other than zero!
 367              */
 368             WalkState->ReturnDesc = WalkState->Operands[0];
 369         }
 370         else if (WalkState->ResultCount)
 371         {
 372             /* Since we have a real Return(), delete any implicit return */
 373
 374             AcpiDsClearImplicitReturn (WalkState);
 375
 376             /*
 377              * The return value has come from a previous calculation.
 378              *
 379              * If value being returned is a Reference (such as
 380              * an arg or local), resolve it now because it may
 381              * cease to exist at the end of the method.
 382              *
 383              * Allow references created by the Index operator to return
 384              * unchanged.
 385              */
 386             if ((ACPI_GET_DESCRIPTOR_TYPE (WalkState->Results->Results.ObjDesc[0]) == ACPI_DESC_TYPE_OPERAND) &&
 387                 ((WalkState->Results->Results.ObjDesc [0])->Common.Type == ACPI_TYPE_LOCAL_REFERENCE) &&
 388                 ((WalkState->Results->Results.ObjDesc [0])->Reference.Class != ACPI_REFCLASS_INDEX))
 389             {
 390                 Status = AcpiExResolveToValue (&WalkState->Results->Results.ObjDesc [0], WalkState);
 391                 if (ACPI_FAILURE (Status))
 392                 {
 393                     return (Status);
 394                 }
 395             }
 396
 397             WalkState->ReturnDesc = WalkState->Results->Results.ObjDesc [0];
 398         }
 399         else
 400         {
 401             /* No return operand */
 402
 403             if (WalkState->NumOperands)
 404             {
 405                 AcpiUtRemoveReference (WalkState->Operands [0]);
 406             }
 407
 408             WalkState->Operands [0]     = NULL;
 409             WalkState->NumOperands      = 0;
 410             WalkState->ReturnDesc       = NULL;
 411         }
 412
 413
 414         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
 415             "Completed RETURN_OP State=%p, RetVal=%p\n",
 416             WalkState, WalkState->ReturnDesc));
 417
 418         /* End the control method execution right now */
 419
 420         Status = AE_CTRL_TERMINATE;
 421         break;
 422
 423
 424     case AML_NOOP_OP:
 425
 426         /* Just do nothing! */
 427         break;
 428
 429
 430     case AML_BREAK_POINT_OP:
 431
 432         /*
 433          * Set the single-step flag. This will cause the debugger (if present)
 434          * to break to the console within the AML debugger at the start of the
 435          * next AML instruction.
 436          */
 437         ACPI_DEBUGGER_EXEC (
 438             AcpiGbl_CmSingleStep = TRUE);
 439         ACPI_DEBUGGER_EXEC (
 440             AcpiOsPrintf ("**break** Executed AML BreakPoint opcode\n"));
 441
 442         /* Call to the OSL in case OS wants a piece of the action */
 443
 444         Status = AcpiOsSignal (ACPI_SIGNAL_BREAKPOINT,
 445                     "Executed AML Breakpoint opcode");
 446         break;
 447
 448
 449     case AML_BREAK_OP:
 450     case AML_CONTINUE_OP: /* ACPI 2.0 */
 451
 452
 453         /* Pop and delete control states until we find a while */
 454
 455         while (WalkState->ControlState &&
 456                 (WalkState->ControlState->Control.Opcode != AML_WHILE_OP))
 457         {
 458             ControlState = AcpiUtPopGenericState (&WalkState->ControlState);
 459             AcpiUtDeleteGenericState (ControlState);
 460         }
 461
 462         /* No while found? */
 463
 464         if (!WalkState->ControlState)
 465         {
 466             return (AE_AML_NO_WHILE);
 467         }
 468
 469         /* Was: WalkState->AmlLastWhile = WalkState->ControlState->Control.AmlPredicateStart; */
 470
 471         WalkState->AmlLastWhile = WalkState->ControlState->Control.PackageEnd;
 472
 473         /* Return status depending on opcode */
 474
 475         if (Op->Common.AmlOpcode == AML_BREAK_OP)
 476         {
 477             Status = AE_CTRL_BREAK;
 478         }
 479         else
 480         {
 481             Status = AE_CTRL_CONTINUE;
 482         }
 483         break;
 484
 485
 486     default:
 487
 488         ACPI_ERROR ((AE_INFO, "Unknown control opcode=0x%X Op=%p",
 489             Op->Common.AmlOpcode, Op));
 490
 491         Status = AE_AML_BAD_OPCODE;
 492         break;
 493     }
 494
 495     return (Status);
 496 }