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      1 /******************************************************************************
      2  *
      3  * Module Name: evgpeinit - System GPE initialization and update
      4  *
      5  *****************************************************************************/
      6 
      7 /******************************************************************************
      8  *
      9  * 1. Copyright Notice
     10  *
     11  * Some or all of this work - Copyright (c) 1999 - 2025, Intel Corp.
     12  * All rights reserved.
     13  *
     14  * 2. License
     15  *
     16  * 2.1. This is your license from Intel Corp. under its intellectual property
     17  * rights. You may have additional license terms from the party that provided
     18  * you this software, covering your right to use that party's intellectual
     19  * property rights.
     20  *
     21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
     22  * copy of the source code appearing in this file ("Covered Code") an
     23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
     24  * base code distributed originally by Intel ("Original Intel Code") to copy,
     25  * make derivatives, distribute, use and display any portion of the Covered
     26  * Code in any form, with the right to sublicense such rights; and
     27  *
     28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
     29  * license (with the right to sublicense), under only those claims of Intel
     30  * patents that are infringed by the Original Intel Code, to make, use, sell,
     31  * offer to sell, and import the Covered Code and derivative works thereof
     32  * solely to the minimum extent necessary to exercise the above copyright
     33  * license, and in no event shall the patent license extend to any additions
     34  * to or modifications of the Original Intel Code. No other license or right
     35  * is granted directly or by implication, estoppel or otherwise;
     36  *
     37  * The above copyright and patent license is granted only if the following
     38  * conditions are met:
     39  *
     40  * 3. Conditions
     41  *
     42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
     43  * Redistribution of source code of any substantial portion of the Covered
     44  * Code or modification with rights to further distribute source must include
     45  * the above Copyright Notice, the above License, this list of Conditions,
     46  * and the following Disclaimer and Export Compliance provision. In addition,
     47  * Licensee must cause all Covered Code to which Licensee contributes to
     48  * contain a file documenting the changes Licensee made to create that Covered
     49  * Code and the date of any change. Licensee must include in that file the
     50  * documentation of any changes made by any predecessor Licensee. Licensee
     51  * must include a prominent statement that the modification is derived,
     52  * directly or indirectly, from Original Intel Code.
     53  *
     54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
     55  * Redistribution of source code of any substantial portion of the Covered
     56  * Code or modification without rights to further distribute source must
     57  * include the following Disclaimer and Export Compliance provision in the
     58  * documentation and/or other materials provided with distribution. In
     59  * addition, Licensee may not authorize further sublicense of source of any
     60  * portion of the Covered Code, and must include terms to the effect that the
     61  * license from Licensee to its licensee is limited to the intellectual
     62  * property embodied in the software Licensee provides to its licensee, and
     63  * not to intellectual property embodied in modifications its licensee may
     64  * make.
     65  *
     66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
     67  * substantial portion of the Covered Code or modification must reproduce the
     68  * above Copyright Notice, and the following Disclaimer and Export Compliance
     69  * provision in the documentation and/or other materials provided with the
     70  * distribution.
     71  *
     72  * 3.4. Intel retains all right, title, and interest in and to the Original
     73  * Intel Code.
     74  *
     75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
     76  * Intel shall be used in advertising or otherwise to promote the sale, use or
     77  * other dealings in products derived from or relating to the Covered Code
     78  * without prior written authorization from Intel.
     79  *
     80  * 4. Disclaimer and Export Compliance
     81  *
     82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
     83  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
     84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
     85  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
     86  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
     87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
     88  * PARTICULAR PURPOSE.
     89  *
     90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
     91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
     92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
     93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
     94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
     95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
     96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
     97  * LIMITED REMEDY.
     98  *
     99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
    100  * software or system incorporating such software without first obtaining any
    101  * required license or other approval from the U. S. Department of Commerce or
    102  * any other agency or department of the United States Government. In the
    103  * event Licensee exports any such software from the United States or
    104  * re-exports any such software from a foreign destination, Licensee shall
    105  * ensure that the distribution and export/re-export of the software is in
    106  * compliance with all laws, regulations, orders, or other restrictions of the
    107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
    108  * any of its subsidiaries will export/re-export any technical data, process,
    109  * software, or service, directly or indirectly, to any country for which the
    110  * United States government or any agency thereof requires an export license,
    111  * other governmental approval, or letter of assurance, without first obtaining
    112  * such license, approval or letter.
    113  *
    114  *****************************************************************************
    115  *
    116  * Alternatively, you may choose to be licensed under the terms of the
    117  * following license:
    118  *
    119  * Redistribution and use in source and binary forms, with or without
    120  * modification, are permitted provided that the following conditions
    121  * are met:
    122  * 1. Redistributions of source code must retain the above copyright
    123  *    notice, this list of conditions, and the following disclaimer,
    124  *    without modification.
    125  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
    126  *    substantially similar to the "NO WARRANTY" disclaimer below
    127  *    ("Disclaimer") and any redistribution must be conditioned upon
    128  *    including a substantially similar Disclaimer requirement for further
    129  *    binary redistribution.
    130  * 3. Neither the names of the above-listed copyright holders nor the names
    131  *    of any contributors may be used to endorse or promote products derived
    132  *    from this software without specific prior written permission.
    133  *
    134  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    135  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    136  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
    137  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
    138  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
    139  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
    140  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
    141  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
    142  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
    143  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
    144  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    145  *
    146  * Alternatively, you may choose to be licensed under the terms of the
    147  * GNU General Public License ("GPL") version 2 as published by the Free
    148  * Software Foundation.
    149  *
    150  *****************************************************************************/
    151 
    152 #include "acpi.h"
    153 #include "accommon.h"
    154 #include "acevents.h"
    155 #include "acnamesp.h"
    156 
    157 #define _COMPONENT          ACPI_EVENTS
    158         ACPI_MODULE_NAME    ("evgpeinit")
    159 
    160 #if (!ACPI_REDUCED_HARDWARE) /* Entire module */
    161 
    162 /*
    163  * Note: History of _PRW support in ACPICA
    164  *
    165  * Originally (2000 - 2010), the GPE initialization code performed a walk of
    166  * the entire namespace to execute the _PRW methods and detect all GPEs
    167  * capable of waking the system.
    168  *
    169  * As of 10/2010, the _PRW method execution has been removed since it is
    170  * actually unnecessary. The host OS must in fact execute all _PRW methods
    171  * in order to identify the device/power-resource dependencies. We now put
    172  * the onus on the host OS to identify the wake GPEs as part of this process
    173  * and to inform ACPICA of these GPEs via the AcpiSetupGpeForWake interface. This
    174  * not only reduces the complexity of the ACPICA initialization code, but in
    175  * some cases (on systems with very large namespaces) it should reduce the
    176  * kernel boot time as well.
    177  */
    178 
    179 /*******************************************************************************
    180  *
    181  * FUNCTION:    AcpiEvGpeInitialize
    182  *
    183  * PARAMETERS:  None
    184  *
    185  * RETURN:      Status
    186  *
    187  * DESCRIPTION: Initialize the GPE data structures and the FADT GPE 0/1 blocks
    188  *
    189  ******************************************************************************/
    190 
    191 ACPI_STATUS
    192 AcpiEvGpeInitialize (
    193     void)
    194 {
    195     UINT32                  RegisterCount0 = 0;
    196     UINT32                  RegisterCount1 = 0;
    197     UINT32                  GpeNumberMax = 0;
    198     ACPI_STATUS             Status;
    199 
    200 
    201     ACPI_FUNCTION_TRACE (EvGpeInitialize);
    202 
    203 
    204     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT,
    205         "Initializing General Purpose Events (GPEs):\n"));
    206 
    207     Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
    208     if (ACPI_FAILURE (Status))
    209     {
    210         return_ACPI_STATUS (Status);
    211     }
    212 
    213     /*
    214      * Initialize the GPE Block(s) defined in the FADT
    215      *
    216      * Why the GPE register block lengths are divided by 2:  From the ACPI
    217      * Spec, section "General-Purpose Event Registers", we have:
    218      *
    219      * "Each register block contains two registers of equal length
    220      *  GPEx_STS and GPEx_EN (where x is 0 or 1). The length of the
    221      *  GPE0_STS and GPE0_EN registers is equal to half the GPE0_LEN
    222      *  The length of the GPE1_STS and GPE1_EN registers is equal to
    223      *  half the GPE1_LEN. If a generic register block is not supported
    224      *  then its respective block pointer and block length values in the
    225      *  FADT table contain zeros. The GPE0_LEN and GPE1_LEN do not need
    226      *  to be the same size."
    227      */
    228 
    229     /*
    230      * Determine the maximum GPE number for this machine.
    231      *
    232      * Note: both GPE0 and GPE1 are optional, and either can exist without
    233      * the other.
    234      *
    235      * If EITHER the register length OR the block address are zero, then that
    236      * particular block is not supported.
    237      */
    238     if (AcpiGbl_FADT.Gpe0BlockLength &&
    239         AcpiGbl_FADT.XGpe0Block.Address)
    240     {
    241         /* GPE block 0 exists (has both length and address > 0) */
    242 
    243         RegisterCount0 = (UINT16) (AcpiGbl_FADT.Gpe0BlockLength / 2);
    244         GpeNumberMax = (RegisterCount0 * ACPI_GPE_REGISTER_WIDTH) - 1;
    245 
    246         /* Install GPE Block 0 */
    247 
    248         Status = AcpiEvCreateGpeBlock (AcpiGbl_FadtGpeDevice,
    249             AcpiGbl_FADT.XGpe0Block.Address,
    250             AcpiGbl_FADT.XGpe0Block.SpaceId,
    251             RegisterCount0, 0,
    252             AcpiGbl_FADT.SciInterrupt, &AcpiGbl_GpeFadtBlocks[0]);
    253 
    254         if (ACPI_FAILURE (Status))
    255         {
    256             ACPI_EXCEPTION ((AE_INFO, Status,
    257                 "Could not create GPE Block 0"));
    258         }
    259     }
    260 
    261     if (AcpiGbl_FADT.Gpe1BlockLength &&
    262         AcpiGbl_FADT.XGpe1Block.Address)
    263     {
    264         /* GPE block 1 exists (has both length and address > 0) */
    265 
    266         RegisterCount1 = (UINT16) (AcpiGbl_FADT.Gpe1BlockLength / 2);
    267 
    268         /* Check for GPE0/GPE1 overlap (if both banks exist) */
    269 
    270         if ((RegisterCount0) &&
    271             (GpeNumberMax >= AcpiGbl_FADT.Gpe1Base))
    272         {
    273             ACPI_ERROR ((AE_INFO,
    274                 "GPE0 block (GPE 0 to %u) overlaps the GPE1 block "
    275                 "(GPE %u to %u) - Ignoring GPE1",
    276                 GpeNumberMax, AcpiGbl_FADT.Gpe1Base,
    277                 AcpiGbl_FADT.Gpe1Base +
    278                 ((RegisterCount1 * ACPI_GPE_REGISTER_WIDTH) - 1)));
    279 
    280             /* Ignore GPE1 block by setting the register count to zero */
    281 
    282             RegisterCount1 = 0;
    283         }
    284         else
    285         {
    286             /* Install GPE Block 1 */
    287 
    288             Status = AcpiEvCreateGpeBlock (AcpiGbl_FadtGpeDevice,
    289                 AcpiGbl_FADT.XGpe1Block.Address,
    290                 AcpiGbl_FADT.XGpe1Block.SpaceId,
    291                 RegisterCount1,
    292                 AcpiGbl_FADT.Gpe1Base,
    293                 AcpiGbl_FADT.SciInterrupt, &AcpiGbl_GpeFadtBlocks[1]);
    294 
    295             if (ACPI_FAILURE (Status))
    296             {
    297                 ACPI_EXCEPTION ((AE_INFO, Status,
    298                     "Could not create GPE Block 1"));
    299             }
    300 
    301             /*
    302              * GPE0 and GPE1 do not have to be contiguous in the GPE number
    303              * space. However, GPE0 always starts at GPE number zero.
    304              */
    305         }
    306     }
    307 
    308     /* Exit if there are no GPE registers */
    309 
    310     if ((RegisterCount0 + RegisterCount1) == 0)
    311     {
    312         /* GPEs are not required by ACPI, this is OK */
    313 
    314         ACPI_DEBUG_PRINT ((ACPI_DB_INIT,
    315             "There are no GPE blocks defined in the FADT\n"));
    316         goto Cleanup;
    317     }
    318 
    319 
    320 Cleanup:
    321     (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
    322     return_ACPI_STATUS (AE_OK);
    323 }
    324 
    325 
    326 /*******************************************************************************
    327  *
    328  * FUNCTION:    AcpiEvUpdateGpes
    329  *
    330  * PARAMETERS:  TableOwnerId        - ID of the newly-loaded ACPI table
    331  *
    332  * RETURN:      None
    333  *
    334  * DESCRIPTION: Check for new GPE methods (_Lxx/_Exx) made available as a
    335  *              result of a Load() or LoadTable() operation. If new GPE
    336  *              methods have been installed, register the new methods.
    337  *
    338  ******************************************************************************/
    339 
    340 void
    341 AcpiEvUpdateGpes (
    342     ACPI_OWNER_ID           TableOwnerId)
    343 {
    344     ACPI_GPE_XRUPT_INFO     *GpeXruptInfo;
    345     ACPI_GPE_BLOCK_INFO     *GpeBlock;
    346     ACPI_GPE_WALK_INFO      WalkInfo;
    347     ACPI_STATUS             Status = AE_OK;
    348 
    349 
    350     /*
    351      * Find any _Lxx/_Exx GPE methods that have just been loaded.
    352      *
    353      * Any GPEs that correspond to new _Lxx/_Exx methods are immediately
    354      * enabled.
    355      *
    356      * Examine the namespace underneath each GpeDevice within the
    357      * GpeBlock lists.
    358      */
    359     Status = AcpiUtAcquireMutex (ACPI_MTX_EVENTS);
    360     if (ACPI_FAILURE (Status))
    361     {
    362         return;
    363     }
    364 
    365     WalkInfo.Count = 0;
    366     WalkInfo.OwnerId = TableOwnerId;
    367     WalkInfo.ExecuteByOwnerId = TRUE;
    368 
    369     /* Walk the interrupt level descriptor list */
    370 
    371     GpeXruptInfo = AcpiGbl_GpeXruptListHead;
    372     while (GpeXruptInfo)
    373     {
    374         /* Walk all Gpe Blocks attached to this interrupt level */
    375 
    376         GpeBlock = GpeXruptInfo->GpeBlockListHead;
    377         while (GpeBlock)
    378         {
    379             WalkInfo.GpeBlock = GpeBlock;
    380             WalkInfo.GpeDevice = GpeBlock->Node;
    381 
    382             Status = AcpiNsWalkNamespace (ACPI_TYPE_METHOD,
    383                 WalkInfo.GpeDevice, ACPI_UINT32_MAX,
    384                 ACPI_NS_WALK_NO_UNLOCK, AcpiEvMatchGpeMethod,
    385                 NULL, &WalkInfo, NULL);
    386             if (ACPI_FAILURE (Status))
    387             {
    388                 ACPI_EXCEPTION ((AE_INFO, Status,
    389                     "While decoding _Lxx/_Exx methods"));
    390             }
    391 
    392             GpeBlock = GpeBlock->Next;
    393         }
    394 
    395         GpeXruptInfo = GpeXruptInfo->Next;
    396     }
    397 
    398     if (WalkInfo.Count)
    399     {
    400         ACPI_INFO (("Enabled %u new GPEs", WalkInfo.Count));
    401     }
    402 
    403     (void) AcpiUtReleaseMutex (ACPI_MTX_EVENTS);
    404     return;
    405 }
    406 
    407 
    408 /*******************************************************************************
    409  *
    410  * FUNCTION:    AcpiEvMatchGpeMethod
    411  *
    412  * PARAMETERS:  Callback from WalkNamespace
    413  *
    414  * RETURN:      Status
    415  *
    416  * DESCRIPTION: Called from AcpiWalkNamespace. Expects each object to be a
    417  *              control method under the _GPE portion of the namespace.
    418  *              Extract the name and GPE type from the object, saving this
    419  *              information for quick lookup during GPE dispatch. Allows a
    420  *              per-OwnerId evaluation if ExecuteByOwnerId is TRUE in the
    421  *              WalkInfo parameter block.
    422  *
    423  *              The name of each GPE control method is of the form:
    424  *              "_Lxx" or "_Exx", where:
    425  *                  L      - means that the GPE is level triggered
    426  *                  E      - means that the GPE is edge triggered
    427  *                  xx     - is the GPE number [in HEX]
    428  *
    429  * If WalkInfo->ExecuteByOwnerId is TRUE, we only execute examine GPE methods
    430  * with that owner.
    431  *
    432  ******************************************************************************/
    433 
    434 ACPI_STATUS
    435 AcpiEvMatchGpeMethod (
    436     ACPI_HANDLE             ObjHandle,
    437     UINT32                  Level,
    438     void                    *Context,
    439     void                    **ReturnValue)
    440 {
    441     ACPI_NAMESPACE_NODE     *MethodNode = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, ObjHandle);
    442     ACPI_GPE_WALK_INFO      *WalkInfo = ACPI_CAST_PTR (ACPI_GPE_WALK_INFO, Context);
    443     ACPI_GPE_EVENT_INFO     *GpeEventInfo;
    444     ACPI_STATUS             Status;
    445     UINT32                  GpeNumber;
    446     UINT8                   TempGpeNumber;
    447     char                    Name[ACPI_NAMESEG_SIZE + 1];
    448     UINT8                   Type;
    449 
    450 
    451     ACPI_FUNCTION_TRACE (EvMatchGpeMethod);
    452 
    453 
    454     /* Check if requested OwnerId matches this OwnerId */
    455 
    456     if ((WalkInfo->ExecuteByOwnerId) &&
    457         (MethodNode->OwnerId != WalkInfo->OwnerId))
    458     {
    459         return_ACPI_STATUS (AE_OK);
    460     }
    461 
    462     /*
    463      * Match and decode the _Lxx and _Exx GPE method names
    464      *
    465      * 1) Extract the method name and null terminate it
    466      */
    467     ACPI_MOVE_32_TO_32 (Name, &MethodNode->Name.Integer);
    468     Name[ACPI_NAMESEG_SIZE] = 0;
    469 
    470     /* 2) Name must begin with an underscore */
    471 
    472     if (Name[0] != '_')
    473     {
    474         return_ACPI_STATUS (AE_OK); /* Ignore this method */
    475     }
    476 
    477     /*
    478      * 3) Edge/Level determination is based on the 2nd character
    479      *    of the method name
    480      */
    481     switch (Name[1])
    482     {
    483     case 'L':
    484 
    485         Type = ACPI_GPE_LEVEL_TRIGGERED;
    486         break;
    487 
    488     case 'E':
    489 
    490         Type = ACPI_GPE_EDGE_TRIGGERED;
    491         break;
    492 
    493     default:
    494 
    495         /* Unknown method type, just ignore it */
    496 
    497         ACPI_DEBUG_PRINT ((ACPI_DB_LOAD,
    498             "Ignoring unknown GPE method type: %s "
    499             "(name not of form _Lxx or _Exx)", Name));
    500         return_ACPI_STATUS (AE_OK);
    501     }
    502 
    503     /* 4) The last two characters of the name are the hex GPE Number */
    504 
    505     Status = AcpiUtAsciiToHexByte (&Name[2], &TempGpeNumber);
    506     if (ACPI_FAILURE (Status))
    507     {
    508         /* Conversion failed; invalid method, just ignore it */
    509 
    510         ACPI_DEBUG_PRINT ((ACPI_DB_LOAD,
    511             "Could not extract GPE number from name: %s "
    512             "(name is not of form _Lxx or _Exx)", Name));
    513         return_ACPI_STATUS (AE_OK);
    514     }
    515 
    516     /* Ensure that we have a valid GPE number for this GPE block */
    517 
    518     GpeNumber = (UINT32) TempGpeNumber;
    519     GpeEventInfo = AcpiEvLowGetGpeInfo (GpeNumber, WalkInfo->GpeBlock);
    520     if (!GpeEventInfo)
    521     {
    522         /*
    523          * This GpeNumber is not valid for this GPE block, just ignore it.
    524          * However, it may be valid for a different GPE block, since GPE0
    525          * and GPE1 methods both appear under \_GPE.
    526          */
    527         return_ACPI_STATUS (AE_OK);
    528     }
    529 
    530     if ((ACPI_GPE_DISPATCH_TYPE (GpeEventInfo->Flags) ==
    531             ACPI_GPE_DISPATCH_HANDLER) ||
    532         (ACPI_GPE_DISPATCH_TYPE (GpeEventInfo->Flags) ==
    533             ACPI_GPE_DISPATCH_RAW_HANDLER))
    534     {
    535         /* If there is already a handler, ignore this GPE method */
    536 
    537         return_ACPI_STATUS (AE_OK);
    538     }
    539 
    540     if (ACPI_GPE_DISPATCH_TYPE (GpeEventInfo->Flags) ==
    541         ACPI_GPE_DISPATCH_METHOD)
    542     {
    543         /*
    544          * If there is already a method, ignore this method. But check
    545          * for a type mismatch (if both the _Lxx AND _Exx exist)
    546          */
    547         if (Type != (GpeEventInfo->Flags & ACPI_GPE_XRUPT_TYPE_MASK))
    548         {
    549             ACPI_ERROR ((AE_INFO,
    550                 "For GPE 0x%.2X, found both _L%2.2X and _E%2.2X methods",
    551                 GpeNumber, GpeNumber, GpeNumber));
    552         }
    553         return_ACPI_STATUS (AE_OK);
    554     }
    555 
    556     /* Disable the GPE in case it's been enabled already. */
    557 
    558     (void) AcpiHwLowSetGpe (GpeEventInfo, ACPI_GPE_DISABLE);
    559 
    560     /*
    561      * Add the GPE information from above to the GpeEventInfo block for
    562      * use during dispatch of this GPE.
    563      */
    564     GpeEventInfo->Flags &= ~(ACPI_GPE_DISPATCH_MASK);
    565     GpeEventInfo->Flags |= (UINT8) (Type | ACPI_GPE_DISPATCH_METHOD);
    566     GpeEventInfo->Dispatch.MethodNode = MethodNode;
    567     WalkInfo->Count++;
    568 
    569     ACPI_DEBUG_PRINT ((ACPI_DB_LOAD,
    570         "Registered GPE method %s as GPE number 0x%.2X\n",
    571         Name, GpeNumber));
    572     return_ACPI_STATUS (AE_OK);
    573 }
    574 
    575 #endif /* !ACPI_REDUCED_HARDWARE */
    576