acpica/dispatcher/dscontrol.c

0001 /******************************************************************************
0002  *
0003  * Module Name: dscontrol - Support for execution control opcodes -
0004  *                          if/else/while/return
0005  *
0006  *****************************************************************************/
0007
0008 /******************************************************************************
0009  *
0010  * 1. Copyright Notice
0011  *
0012  * Some or all of this work - Copyright (c) 1999 - 2024, Intel Corp.
0013  * All rights reserved.
0014  *
0015  * 2. License
0016  *
0017  * 2.1. This is your license from Intel Corp. under its intellectual property
0018  * rights. You may have additional license terms from the party that provided
0019  * you this software, covering your right to use that party's intellectual
0020  * property rights.
0021  *
0022  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
0023  * copy of the source code appearing in this file ("Covered Code") an
0024  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
0025  * base code distributed originally by Intel ("Original Intel Code") to copy,
0026  * make derivatives, distribute, use and display any portion of the Covered
0027  * Code in any form, with the right to sublicense such rights; and
0028  *
0029  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
0030  * license (with the right to sublicense), under only those claims of Intel
0031  * patents that are infringed by the Original Intel Code, to make, use, sell,
0032  * offer to sell, and import the Covered Code and derivative works thereof
0033  * solely to the minimum extent necessary to exercise the above copyright
0034  * license, and in no event shall the patent license extend to any additions
0035  * to or modifications of the Original Intel Code. No other license or right
0036  * is granted directly or by implication, estoppel or otherwise;
0037  *
0038  * The above copyright and patent license is granted only if the following
0039  * conditions are met:
0040  *
0041  * 3. Conditions
0042  *
0043  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
0044  * Redistribution of source code of any substantial portion of the Covered
0045  * Code or modification with rights to further distribute source must include
0046  * the above Copyright Notice, the above License, this list of Conditions,
0047  * and the following Disclaimer and Export Compliance provision. In addition,
0048  * Licensee must cause all Covered Code to which Licensee contributes to
0049  * contain a file documenting the changes Licensee made to create that Covered
0050  * Code and the date of any change. Licensee must include in that file the
0051  * documentation of any changes made by any predecessor Licensee. Licensee
0052  * must include a prominent statement that the modification is derived,
0053  * directly or indirectly, from Original Intel Code.
0054  *
0055  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
0056  * Redistribution of source code of any substantial portion of the Covered
0057  * Code or modification without rights to further distribute source must
0058  * include the following Disclaimer and Export Compliance provision in the
0059  * documentation and/or other materials provided with distribution. In
0060  * addition, Licensee may not authorize further sublicense of source of any
0061  * portion of the Covered Code, and must include terms to the effect that the
0062  * license from Licensee to its licensee is limited to the intellectual
0063  * property embodied in the software Licensee provides to its licensee, and
0064  * not to intellectual property embodied in modifications its licensee may
0065  * make.
0066  *
0067  * 3.3. Redistribution of Executable. Redistribution in executable form of any
0068  * substantial portion of the Covered Code or modification must reproduce the
0069  * above Copyright Notice, and the following Disclaimer and Export Compliance
0070  * provision in the documentation and/or other materials provided with the
0071  * distribution.
0072  *
0073  * 3.4. Intel retains all right, title, and interest in and to the Original
0074  * Intel Code.
0075  *
0076  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
0077  * Intel shall be used in advertising or otherwise to promote the sale, use or
0078  * other dealings in products derived from or relating to the Covered Code
0079  * without prior written authorization from Intel.
0080  *
0081  * 4. Disclaimer and Export Compliance
0082  *
0083  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
0084  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
0085  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
0086  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
0087  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
0088  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
0089  * PARTICULAR PURPOSE.
0090  *
0091  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
0092  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
0093  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
0094  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
0095  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
0096  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
0097  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
0098  * LIMITED REMEDY.
0099  *
0100  * 4.3. Licensee shall not export, either directly or indirectly, any of this
0101  * software or system incorporating such software without first obtaining any
0102  * required license or other approval from the U. S. Department of Commerce or
0103  * any other agency or department of the United States Government. In the
0104  * event Licensee exports any such software from the United States or
0105  * re-exports any such software from a foreign destination, Licensee shall
0106  * ensure that the distribution and export/re-export of the software is in
0107  * compliance with all laws, regulations, orders, or other restrictions of the
0108  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
0109  * any of its subsidiaries will export/re-export any technical data, process,
0110  * software, or service, directly or indirectly, to any country for which the
0111  * United States government or any agency thereof requires an export license,
0112  * other governmental approval, or letter of assurance, without first obtaining
0113  * such license, approval or letter.
0114  *
0115  *****************************************************************************
0116  *
0117  * Alternatively, you may choose to be licensed under the terms of the
0118  * following license:
0119  *
0120  * Redistribution and use in source and binary forms, with or without
0121  * modification, are permitted provided that the following conditions
0122  * are met:
0123  * 1. Redistributions of source code must retain the above copyright
0124  *    notice, this list of conditions, and the following disclaimer,
0125  *    without modification.
0126  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
0127  *    substantially similar to the "NO WARRANTY" disclaimer below
0128  *    ("Disclaimer") and any redistribution must be conditioned upon
0129  *    including a substantially similar Disclaimer requirement for further
0130  *    binary redistribution.
0131  * 3. Neither the names of the above-listed copyright holders nor the names
0132  *    of any contributors may be used to endorse or promote products derived
0133  *    from this software without specific prior written permission.
0134  *
0135  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
0136  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
0137  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
0138  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
0139  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
0140  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
0141  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
0142  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
0143  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
0144  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
0145  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
0146  *
0147  * Alternatively, you may choose to be licensed under the terms of the
0148  * GNU General Public License ("GPL") version 2 as published by the Free
0149  * Software Foundation.
0150  *
0151  *****************************************************************************/
0152
0153 #include "acpi.h"
0154 #include "accommon.h"
0155 #include "amlcode.h"
0156 #include "acdispat.h"
0157 #include "acinterp.h"
0158 #include "acdebug.h"
0159
0160 #define _COMPONENT          ACPI_DISPATCHER
0161         ACPI_MODULE_NAME    ("dscontrol")
0162
0163
0164 /*******************************************************************************
0165  *
0166  * FUNCTION:    AcpiDsExecBeginControlOp
0167  *
0168  * PARAMETERS:  WalkList        - The list that owns the walk stack
0169  *              Op              - The control Op
0170  *
0171  * RETURN:      Status
0172  *
0173  * DESCRIPTION: Handles all control ops encountered during control method
0174  *              execution.
0175  *
0176  ******************************************************************************/
0177
0178 ACPI_STATUS
0179 AcpiDsExecBeginControlOp (
0180     ACPI_WALK_STATE         *WalkState,
0181     ACPI_PARSE_OBJECT       *Op)
0182 {
0183     ACPI_STATUS             Status = AE_OK;
0184     ACPI_GENERIC_STATE      *ControlState;
0185
0186
0187     ACPI_FUNCTION_NAME (DsExecBeginControlOp);
0188
0189
0190     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Op=%p Opcode=%2.2X State=%p\n",
0191         Op, Op->Common.AmlOpcode, WalkState));
0192
0193     switch (Op->Common.AmlOpcode)
0194     {
0195     case AML_WHILE_OP:
0196         /*
0197          * If this is an additional iteration of a while loop, continue.
0198          * There is no need to allocate a new control state.
0199          */
0200         if (WalkState->ControlState)
0201         {
0202             if (WalkState->ControlState->Control.AmlPredicateStart ==
0203                 (WalkState->ParserState.Aml - 1))
0204             {
0205                 /* Reset the state to start-of-loop */
0206
0207                 WalkState->ControlState->Common.State =
0208                     ACPI_CONTROL_CONDITIONAL_EXECUTING;
0209                 break;
0210             }
0211         }
0212
0213         ACPI_FALLTHROUGH;
0214
0215     case AML_IF_OP:
0216         /*
0217          * IF/WHILE: Create a new control state to manage these
0218          * constructs. We need to manage these as a stack, in order
0219          * to handle nesting.
0220          */
0221         ControlState = AcpiUtCreateControlState ();
0222         if (!ControlState)
0223         {
0224             Status = AE_NO_MEMORY;
0225             break;
0226         }
0227         /*
0228          * Save a pointer to the predicate for multiple executions
0229          * of a loop
0230          */
0231         ControlState->Control.AmlPredicateStart =
0232             WalkState->ParserState.Aml - 1;
0233         ControlState->Control.PackageEnd =
0234             WalkState->ParserState.PkgEnd;
0235         ControlState->Control.Opcode =
0236             Op->Common.AmlOpcode;
0237         ControlState->Control.LoopTimeout = AcpiOsGetTimer () +
0238            ((UINT64) AcpiGbl_MaxLoopIterations * ACPI_100NSEC_PER_SEC);
0239
0240         /* Push the control state on this walk's control stack */
0241
0242         AcpiUtPushGenericState (&WalkState->ControlState, ControlState);
0243         break;
0244
0245     case AML_ELSE_OP:
0246
0247         /* Predicate is in the state object */
0248         /* If predicate is true, the IF was executed, ignore ELSE part */
0249
0250         if (WalkState->LastPredicate)
0251         {
0252             Status = AE_CTRL_TRUE;
0253         }
0254
0255         break;
0256
0257     case AML_RETURN_OP:
0258
0259         break;
0260
0261     default:
0262
0263         break;
0264     }
0265
0266     return (Status);
0267 }
0268
0269
0270 /*******************************************************************************
0271  *
0272  * FUNCTION:    AcpiDsExecEndControlOp
0273  *
0274  * PARAMETERS:  WalkList        - The list that owns the walk stack
0275  *              Op              - The control Op
0276  *
0277  * RETURN:      Status
0278  *
0279  * DESCRIPTION: Handles all control ops encountered during control method
0280  *              execution.
0281  *
0282  ******************************************************************************/
0283
0284 ACPI_STATUS
0285 AcpiDsExecEndControlOp (
0286     ACPI_WALK_STATE         *WalkState,
0287     ACPI_PARSE_OBJECT       *Op)
0288 {
0289     ACPI_STATUS             Status = AE_OK;
0290     ACPI_GENERIC_STATE      *ControlState;
0291
0292
0293     ACPI_FUNCTION_NAME (DsExecEndControlOp);
0294
0295
0296     switch (Op->Common.AmlOpcode)
0297     {
0298     case AML_IF_OP:
0299
0300         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "[IF_OP] Op=%p\n", Op));
0301
0302         /*
0303          * Save the result of the predicate in case there is an
0304          * ELSE to come
0305          */
0306         WalkState->LastPredicate =
0307             (BOOLEAN) WalkState->ControlState->Common.Value;
0308
0309         /*
0310          * Pop the control state that was created at the start
0311          * of the IF and free it
0312          */
0313         ControlState = AcpiUtPopGenericState (&WalkState->ControlState);
0314         AcpiUtDeleteGenericState (ControlState);
0315         break;
0316
0317     case AML_ELSE_OP:
0318
0319         break;
0320
0321     case AML_WHILE_OP:
0322
0323         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "[WHILE_OP] Op=%p\n", Op));
0324
0325         ControlState = WalkState->ControlState;
0326         if (ControlState->Common.Value)
0327         {
0328             /* Predicate was true, the body of the loop was just executed */
0329
0330             /*
0331              * This infinite loop detection mechanism allows the interpreter
0332              * to escape possibly infinite loops. This can occur in poorly
0333              * written AML when the hardware does not respond within a while
0334              * loop and the loop does not implement a timeout.
0335              */
0336             if (ACPI_TIME_AFTER (AcpiOsGetTimer (),
0337                     ControlState->Control.LoopTimeout))
0338             {
0339                 Status = AE_AML_LOOP_TIMEOUT;
0340                 break;
0341             }
0342
0343             /*
0344              * Go back and evaluate the predicate and maybe execute the loop
0345              * another time
0346              */
0347             Status = AE_CTRL_PENDING;
0348             WalkState->AmlLastWhile =
0349                 ControlState->Control.AmlPredicateStart;
0350             break;
0351         }
0352
0353         /* Predicate was false, terminate this while loop */
0354
0355         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
0356             "[WHILE_OP] termination! Op=%p\n",Op));
0357
0358         /* Pop this control state and free it */
0359
0360         ControlState = AcpiUtPopGenericState (&WalkState->ControlState);
0361         AcpiUtDeleteGenericState (ControlState);
0362         break;
0363
0364     case AML_RETURN_OP:
0365
0366         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
0367             "[RETURN_OP] Op=%p Arg=%p\n",Op, Op->Common.Value.Arg));
0368
0369         /*
0370          * One optional operand -- the return value
0371          * It can be either an immediate operand or a result that
0372          * has been bubbled up the tree
0373          */
0374         if (Op->Common.Value.Arg)
0375         {
0376             /* Since we have a real Return(), delete any implicit return */
0377
0378             AcpiDsClearImplicitReturn (WalkState);
0379
0380             /* Return statement has an immediate operand */
0381
0382             Status = AcpiDsCreateOperands (WalkState, Op->Common.Value.Arg);
0383             if (ACPI_FAILURE (Status))
0384             {
0385                 return (Status);
0386             }
0387
0388             /*
0389              * If value being returned is a Reference (such as
0390              * an arg or local), resolve it now because it may
0391              * cease to exist at the end of the method.
0392              */
0393             Status = AcpiExResolveToValue (
0394                 &WalkState->Operands [0], WalkState);
0395             if (ACPI_FAILURE (Status))
0396             {
0397                 return (Status);
0398             }
0399
0400             /*
0401              * Get the return value and save as the last result
0402              * value. This is the only place where WalkState->ReturnDesc
0403              * is set to anything other than zero!
0404              */
0405             WalkState->ReturnDesc = WalkState->Operands[0];
0406         }
0407         else if (WalkState->ResultCount)
0408         {
0409             /* Since we have a real Return(), delete any implicit return */
0410
0411             AcpiDsClearImplicitReturn (WalkState);
0412
0413             /*
0414              * The return value has come from a previous calculation.
0415              *
0416              * If value being returned is a Reference (such as
0417              * an arg or local), resolve it now because it may
0418              * cease to exist at the end of the method.
0419              *
0420              * Allow references created by the Index operator to return
0421              * unchanged.
0422              */
0423             if ((ACPI_GET_DESCRIPTOR_TYPE (WalkState->Results->Results.ObjDesc[0]) ==
0424                     ACPI_DESC_TYPE_OPERAND) &&
0425                 ((WalkState->Results->Results.ObjDesc [0])->Common.Type ==
0426                     ACPI_TYPE_LOCAL_REFERENCE) &&
0427                 ((WalkState->Results->Results.ObjDesc [0])->Reference.Class !=
0428                     ACPI_REFCLASS_INDEX))
0429             {
0430                 Status = AcpiExResolveToValue (
0431                     &WalkState->Results->Results.ObjDesc [0], WalkState);
0432                 if (ACPI_FAILURE (Status))
0433                 {
0434                     return (Status);
0435                 }
0436             }
0437
0438             WalkState->ReturnDesc = WalkState->Results->Results.ObjDesc [0];
0439         }
0440         else
0441         {
0442             /* No return operand */
0443
0444             if (WalkState->NumOperands)
0445             {
0446                 AcpiUtRemoveReference (WalkState->Operands [0]);
0447             }
0448
0449             WalkState->Operands[0] = NULL;
0450             WalkState->NumOperands = 0;
0451             WalkState->ReturnDesc = NULL;
0452         }
0453
0454
0455         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
0456             "Completed RETURN_OP State=%p, RetVal=%p\n",
0457             WalkState, WalkState->ReturnDesc));
0458
0459         /* End the control method execution right now */
0460
0461         Status = AE_CTRL_TERMINATE;
0462         break;
0463
0464     case AML_NOOP_OP:
0465
0466         /* Just do nothing! */
0467
0468         break;
0469
0470     case AML_BREAKPOINT_OP:
0471
0472         AcpiDbSignalBreakPoint (WalkState);
0473
0474         /* Call to the OSL in case OS wants a piece of the action */
0475
0476         Status = AcpiOsSignal (ACPI_SIGNAL_BREAKPOINT,
0477             "Executed AML Breakpoint opcode");
0478         break;
0479
0480     case AML_BREAK_OP:
0481     case AML_CONTINUE_OP: /* ACPI 2.0 */
0482
0483         /* Pop and delete control states until we find a while */
0484
0485         while (WalkState->ControlState &&
0486                 (WalkState->ControlState->Control.Opcode != AML_WHILE_OP))
0487         {
0488             ControlState = AcpiUtPopGenericState (&WalkState->ControlState);
0489             AcpiUtDeleteGenericState (ControlState);
0490         }
0491
0492         /* No while found? */
0493
0494         if (!WalkState->ControlState)
0495         {
0496             return (AE_AML_NO_WHILE);
0497         }
0498
0499         /* Was: WalkState->AmlLastWhile = WalkState->ControlState->Control.AmlPredicateStart; */
0500
0501         WalkState->AmlLastWhile =
0502             WalkState->ControlState->Control.PackageEnd;
0503
0504         /* Return status depending on opcode */
0505
0506         if (Op->Common.AmlOpcode == AML_BREAK_OP)
0507         {
0508             Status = AE_CTRL_BREAK;
0509         }
0510         else
0511         {
0512             Status = AE_CTRL_CONTINUE;
0513         }
0514         break;
0515
0516     default:
0517
0518         ACPI_ERROR ((AE_INFO, "Unknown control opcode=0x%X Op=%p",
0519             Op->Common.AmlOpcode, Op));
0520
0521         Status = AE_AML_BAD_OPCODE;
0522         break;
0523     }
0524
0525     return (Status);
0526 }