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      1 /******************************************************************************
      2  *
      3  * Module Name: tbxface - ACPI table-oriented external interfaces
      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 #define EXPORT_ACPI_INTERFACES
    153 
    154 #include "acpi.h"
    155 #include "accommon.h"
    156 #include "actables.h"
    157 
    158 #define _COMPONENT          ACPI_TABLES
    159         ACPI_MODULE_NAME    ("tbxface")
    160 
    161 
    162 /*******************************************************************************
    163  *
    164  * FUNCTION:    AcpiAllocateRootTable
    165  *
    166  * PARAMETERS:  InitialTableCount   - Size of InitialTableArray, in number of
    167  *                                    ACPI_TABLE_DESC structures
    168  *
    169  * RETURN:      Status
    170  *
    171  * DESCRIPTION: Allocate a root table array. Used by iASL compiler and
    172  *              AcpiInitializeTables.
    173  *
    174  ******************************************************************************/
    175 
    176 ACPI_STATUS
    177 AcpiAllocateRootTable (
    178     UINT32                  InitialTableCount)
    179 {
    180 
    181     AcpiGbl_RootTableList.MaxTableCount = InitialTableCount;
    182     AcpiGbl_RootTableList.Flags = ACPI_ROOT_ALLOW_RESIZE;
    183 
    184     return (AcpiTbResizeRootTableList ());
    185 }
    186 
    187 
    188 /*******************************************************************************
    189  *
    190  * FUNCTION:    AcpiInitializeTables
    191  *
    192  * PARAMETERS:  InitialTableArray   - Pointer to an array of pre-allocated
    193  *                                    ACPI_TABLE_DESC structures. If NULL, the
    194  *                                    array is dynamically allocated.
    195  *              InitialTableCount   - Size of InitialTableArray, in number of
    196  *                                    ACPI_TABLE_DESC structures
    197  *              AllowResize         - Flag to tell Table Manager if resize of
    198  *                                    pre-allocated array is allowed. Ignored
    199  *                                    if InitialTableArray is NULL.
    200  *
    201  * RETURN:      Status
    202  *
    203  * DESCRIPTION: Initialize the table manager, get the RSDP and RSDT/XSDT.
    204  *
    205  * NOTE:        Allows static allocation of the initial table array in order
    206  *              to avoid the use of dynamic memory in confined environments
    207  *              such as the kernel boot sequence where it may not be available.
    208  *
    209  *              If the host OS memory managers are initialized, use NULL for
    210  *              InitialTableArray, and the table will be dynamically allocated.
    211  *
    212  ******************************************************************************/
    213 
    214 ACPI_STATUS ACPI_INIT_FUNCTION
    215 AcpiInitializeTables (
    216     ACPI_TABLE_DESC         *InitialTableArray,
    217     UINT32                  InitialTableCount,
    218     BOOLEAN                 AllowResize)
    219 {
    220     ACPI_PHYSICAL_ADDRESS   RsdpAddress;
    221     ACPI_STATUS             Status;
    222 
    223 
    224     ACPI_FUNCTION_TRACE (AcpiInitializeTables);
    225 
    226 
    227     /*
    228      * Setup the Root Table Array and allocate the table array
    229      * if requested
    230      */
    231     if (!InitialTableArray)
    232     {
    233         Status = AcpiAllocateRootTable (InitialTableCount);
    234         if (ACPI_FAILURE (Status))
    235         {
    236             return_ACPI_STATUS (Status);
    237         }
    238     }
    239     else
    240     {
    241         /* Root Table Array has been statically allocated by the host */
    242 
    243         memset (InitialTableArray, 0,
    244             (ACPI_SIZE) InitialTableCount * sizeof (ACPI_TABLE_DESC));
    245 
    246         AcpiGbl_RootTableList.Tables = InitialTableArray;
    247         AcpiGbl_RootTableList.MaxTableCount = InitialTableCount;
    248         AcpiGbl_RootTableList.Flags = ACPI_ROOT_ORIGIN_UNKNOWN;
    249         if (AllowResize)
    250         {
    251             AcpiGbl_RootTableList.Flags |= ACPI_ROOT_ALLOW_RESIZE;
    252         }
    253     }
    254 
    255     /* Get the address of the RSDP */
    256 
    257     RsdpAddress = AcpiOsGetRootPointer ();
    258     if (!RsdpAddress)
    259     {
    260         return_ACPI_STATUS (AE_NOT_FOUND);
    261     }
    262 
    263     /*
    264      * Get the root table (RSDT or XSDT) and extract all entries to the local
    265      * Root Table Array. This array contains the information of the RSDT/XSDT
    266      * in a common, more usable format.
    267      */
    268     Status = AcpiTbParseRootTable (RsdpAddress);
    269     return_ACPI_STATUS (Status);
    270 }
    271 
    272 ACPI_EXPORT_SYMBOL_INIT (AcpiInitializeTables)
    273 
    274 
    275 /*******************************************************************************
    276  *
    277  * FUNCTION:    AcpiReallocateRootTable
    278  *
    279  * PARAMETERS:  None
    280  *
    281  * RETURN:      Status
    282  *
    283  * DESCRIPTION: Reallocate Root Table List into dynamic memory. Copies the
    284  *              root list from the previously provided scratch area. Should
    285  *              be called once dynamic memory allocation is available in the
    286  *              kernel.
    287  *
    288  ******************************************************************************/
    289 
    290 ACPI_STATUS ACPI_INIT_FUNCTION
    291 AcpiReallocateRootTable (
    292     void)
    293 {
    294     ACPI_STATUS             Status;
    295     ACPI_TABLE_DESC         *TableDesc;
    296     UINT32                  i, j;
    297 
    298 
    299     ACPI_FUNCTION_TRACE (AcpiReallocateRootTable);
    300 
    301 
    302     /*
    303      * If there are tables unverified, it is required to reallocate the
    304      * root table list to clean up invalid table entries. Otherwise only
    305      * reallocate the root table list if the host provided a static buffer
    306      * for the table array in the call to AcpiInitializeTables().
    307      */
    308     if ((AcpiGbl_RootTableList.Flags & ACPI_ROOT_ORIGIN_ALLOCATED) &&
    309         AcpiGbl_EnableTableValidation)
    310     {
    311         return_ACPI_STATUS (AE_SUPPORT);
    312     }
    313 
    314     (void) AcpiUtAcquireMutex (ACPI_MTX_TABLES);
    315 
    316     /*
    317      * Ensure OS early boot logic, which is required by some hosts. If the
    318      * table state is reported to be wrong, developers should fix the
    319      * issue by invoking AcpiPutTable() for the reported table during the
    320      * early stage.
    321      */
    322     for (i = 0; i < AcpiGbl_RootTableList.CurrentTableCount; ++i)
    323     {
    324         TableDesc = &AcpiGbl_RootTableList.Tables[i];
    325         if (TableDesc->Pointer)
    326         {
    327             ACPI_ERROR ((AE_INFO,
    328                 "Table [%4.4s] is not invalidated during early boot stage",
    329                 TableDesc->Signature.Ascii));
    330         }
    331     }
    332 
    333     if (!AcpiGbl_EnableTableValidation)
    334     {
    335         /*
    336          * Now it's safe to do full table validation. We can do deferred
    337          * table initialization here once the flag is set.
    338          */
    339         AcpiGbl_EnableTableValidation = TRUE;
    340         for (i = 0; i < AcpiGbl_RootTableList.CurrentTableCount; ++i)
    341         {
    342             TableDesc = &AcpiGbl_RootTableList.Tables[i];
    343             if (!(TableDesc->Flags & ACPI_TABLE_IS_VERIFIED))
    344             {
    345                 Status = AcpiTbVerifyTempTable (TableDesc, NULL, &j);
    346                 if (ACPI_FAILURE (Status))
    347                 {
    348                     AcpiTbUninstallTable (TableDesc);
    349                 }
    350             }
    351         }
    352     }
    353 
    354     AcpiGbl_RootTableList.Flags |= ACPI_ROOT_ALLOW_RESIZE;
    355     Status = AcpiTbResizeRootTableList ();
    356     AcpiGbl_RootTableList.Flags |= ACPI_ROOT_ORIGIN_ALLOCATED;
    357 
    358     (void) AcpiUtReleaseMutex (ACPI_MTX_TABLES);
    359     return_ACPI_STATUS (Status);
    360 }
    361 
    362 ACPI_EXPORT_SYMBOL_INIT (AcpiReallocateRootTable)
    363 
    364 
    365 /*******************************************************************************
    366  *
    367  * FUNCTION:    AcpiGetTableHeader
    368  *
    369  * PARAMETERS:  Signature           - ACPI signature of needed table
    370  *              Instance            - Which instance (for SSDTs)
    371  *              OutTableHeader      - The pointer to the where the table header
    372  *                                    is returned
    373  *
    374  * RETURN:      Status and a copy of the table header
    375  *
    376  * DESCRIPTION: Finds and returns an ACPI table header. Caller provides the
    377  *              memory where a copy of the header is to be returned
    378  *              (fixed length).
    379  *
    380  ******************************************************************************/
    381 
    382 ACPI_STATUS
    383 AcpiGetTableHeader (
    384     ACPI_CONST_STRING       Signature,
    385     UINT32                  Instance,
    386     ACPI_TABLE_HEADER       *OutTableHeader)
    387 {
    388     UINT32                  i;
    389     UINT32                  j;
    390     ACPI_TABLE_HEADER       *Header;
    391 
    392 
    393     /* Parameter validation */
    394 
    395     if (!Signature || !OutTableHeader)
    396     {
    397         return (AE_BAD_PARAMETER);
    398     }
    399 
    400     /* Walk the root table list */
    401 
    402     for (i = 0, j = 0; i < AcpiGbl_RootTableList.CurrentTableCount; i++)
    403     {
    404         if (!ACPI_COMPARE_NAMESEG (
    405                 &(AcpiGbl_RootTableList.Tables[i].Signature), Signature))
    406         {
    407             continue;
    408         }
    409 
    410         if (++j < Instance)
    411         {
    412             continue;
    413         }
    414 
    415         if (!AcpiGbl_RootTableList.Tables[i].Pointer)
    416         {
    417             if ((AcpiGbl_RootTableList.Tables[i].Flags &
    418                     ACPI_TABLE_ORIGIN_MASK) ==
    419                 ACPI_TABLE_ORIGIN_INTERNAL_PHYSICAL)
    420             {
    421                 Header = AcpiOsMapMemory (
    422                     AcpiGbl_RootTableList.Tables[i].Address,
    423                     sizeof (ACPI_TABLE_HEADER));
    424                 if (!Header)
    425                 {
    426                     return (AE_NO_MEMORY);
    427                 }
    428 
    429                 memcpy (OutTableHeader, Header, sizeof (ACPI_TABLE_HEADER));
    430                 AcpiOsUnmapMemory (Header, sizeof (ACPI_TABLE_HEADER));
    431             }
    432             else
    433             {
    434                 return (AE_NOT_FOUND);
    435             }
    436         }
    437         else
    438         {
    439             memcpy (OutTableHeader,
    440                 AcpiGbl_RootTableList.Tables[i].Pointer,
    441                 sizeof (ACPI_TABLE_HEADER));
    442         }
    443 
    444         return (AE_OK);
    445     }
    446 
    447     return (AE_NOT_FOUND);
    448 }
    449 
    450 ACPI_EXPORT_SYMBOL (AcpiGetTableHeader)
    451 
    452 
    453 /*******************************************************************************
    454  *
    455  * FUNCTION:    AcpiGetTable
    456  *
    457  * PARAMETERS:  Signature           - ACPI signature of needed table
    458  *              Instance            - Which instance (for SSDTs)
    459  *              OutTable            - Where the pointer to the table is returned
    460  *
    461  * RETURN:      Status and pointer to the requested table
    462  *
    463  * DESCRIPTION: Finds and verifies an ACPI table. Table must be in the
    464  *              RSDT/XSDT.
    465  *              Note that an early stage AcpiGetTable() call must be paired
    466  *              with an early stage AcpiPutTable() call. otherwise the table
    467  *              pointer mapped by the early stage mapping implementation may be
    468  *              erroneously unmapped by the late stage unmapping implementation
    469  *              in an AcpiPutTable() invoked during the late stage.
    470  *
    471  ******************************************************************************/
    472 
    473 ACPI_STATUS
    474 AcpiGetTable (
    475     ACPI_CONST_STRING       Signature,
    476     UINT32                  Instance,
    477     ACPI_TABLE_HEADER       **OutTable)
    478 {
    479     UINT32                  i;
    480     UINT32                  j;
    481     ACPI_STATUS             Status = AE_NOT_FOUND;
    482     ACPI_TABLE_DESC         *TableDesc;
    483 
    484 
    485     /* Parameter validation */
    486 
    487     if (!Signature || !OutTable)
    488     {
    489         return (AE_BAD_PARAMETER);
    490     }
    491 
    492     /*
    493      * Note that the following line is required by some OSPMs, they only
    494      * check if the returned table is NULL instead of the returned status
    495      * to determined if this function is succeeded.
    496      */
    497     *OutTable = NULL;
    498 
    499     (void) AcpiUtAcquireMutex (ACPI_MTX_TABLES);
    500 
    501     /* Walk the root table list */
    502 
    503     for (i = 0, j = 0; i < AcpiGbl_RootTableList.CurrentTableCount; i++)
    504     {
    505         TableDesc = &AcpiGbl_RootTableList.Tables[i];
    506 
    507         if (!ACPI_COMPARE_NAMESEG (&TableDesc->Signature, Signature))
    508         {
    509             continue;
    510         }
    511 
    512         if (++j < Instance)
    513         {
    514             continue;
    515         }
    516 
    517         Status = AcpiTbGetTable (TableDesc, OutTable);
    518         break;
    519     }
    520 
    521     (void) AcpiUtReleaseMutex (ACPI_MTX_TABLES);
    522     return (Status);
    523 }
    524 
    525 ACPI_EXPORT_SYMBOL (AcpiGetTable)
    526 
    527 
    528 /*******************************************************************************
    529  *
    530  * FUNCTION:    AcpiPutTable
    531  *
    532  * PARAMETERS:  Table               - The pointer to the table
    533  *
    534  * RETURN:      None
    535  *
    536  * DESCRIPTION: Release a table returned by AcpiGetTable() and its clones.
    537  *              Note that it is not safe if this function was invoked after an
    538  *              uninstallation happened to the original table descriptor.
    539  *              Currently there is no OSPMs' requirement to handle such
    540  *              situations.
    541  *
    542  ******************************************************************************/
    543 
    544 void
    545 AcpiPutTable (
    546     ACPI_TABLE_HEADER       *Table)
    547 {
    548     UINT32                  i;
    549     ACPI_TABLE_DESC         *TableDesc;
    550 
    551 
    552     ACPI_FUNCTION_TRACE (AcpiPutTable);
    553 
    554 
    555     if (!Table)
    556     {
    557         return_VOID;
    558     }
    559 
    560     (void) AcpiUtAcquireMutex (ACPI_MTX_TABLES);
    561 
    562     /* Walk the root table list */
    563 
    564     for (i = 0; i < AcpiGbl_RootTableList.CurrentTableCount; i++)
    565     {
    566         TableDesc = &AcpiGbl_RootTableList.Tables[i];
    567 
    568         if (TableDesc->Pointer != Table)
    569         {
    570             continue;
    571         }
    572 
    573         AcpiTbPutTable (TableDesc);
    574         break;
    575     }
    576 
    577     (void) AcpiUtReleaseMutex (ACPI_MTX_TABLES);
    578     return_VOID;
    579 }
    580 
    581 ACPI_EXPORT_SYMBOL (AcpiPutTable)
    582 
    583 
    584 /*******************************************************************************
    585  *
    586  * FUNCTION:    AcpiGetTableByIndex
    587  *
    588  * PARAMETERS:  TableIndex          - Table index
    589  *              OutTable            - Where the pointer to the table is returned
    590  *
    591  * RETURN:      Status and pointer to the requested table
    592  *
    593  * DESCRIPTION: Obtain a table by an index into the global table list. Used
    594  *              internally also.
    595  *
    596  ******************************************************************************/
    597 
    598 ACPI_STATUS
    599 AcpiGetTableByIndex (
    600     UINT32                  TableIndex,
    601     ACPI_TABLE_HEADER       **OutTable)
    602 {
    603     ACPI_STATUS             Status;
    604 
    605 
    606     ACPI_FUNCTION_TRACE (AcpiGetTableByIndex);
    607 
    608 
    609     /* Parameter validation */
    610 
    611     if (!OutTable)
    612     {
    613         return_ACPI_STATUS (AE_BAD_PARAMETER);
    614     }
    615 
    616     /*
    617      * Note that the following line is required by some OSPMs, they only
    618      * check if the returned table is NULL instead of the returned status
    619      * to determined if this function is succeeded.
    620      */
    621     *OutTable = NULL;
    622 
    623     (void) AcpiUtAcquireMutex (ACPI_MTX_TABLES);
    624 
    625     /* Validate index */
    626 
    627     if (TableIndex >= AcpiGbl_RootTableList.CurrentTableCount)
    628     {
    629         Status = AE_BAD_PARAMETER;
    630         goto UnlockAndExit;
    631     }
    632 
    633     Status = AcpiTbGetTable (
    634         &AcpiGbl_RootTableList.Tables[TableIndex], OutTable);
    635 
    636 UnlockAndExit:
    637     (void) AcpiUtReleaseMutex (ACPI_MTX_TABLES);
    638     return_ACPI_STATUS (Status);
    639 }
    640 
    641 ACPI_EXPORT_SYMBOL (AcpiGetTableByIndex)
    642 
    643 
    644 /*******************************************************************************
    645  *
    646  * FUNCTION:    AcpiInstallTableHandler
    647  *
    648  * PARAMETERS:  Handler         - Table event handler
    649  *              Context         - Value passed to the handler on each event
    650  *
    651  * RETURN:      Status
    652  *
    653  * DESCRIPTION: Install a global table event handler.
    654  *
    655  ******************************************************************************/
    656 
    657 ACPI_STATUS
    658 AcpiInstallTableHandler (
    659     ACPI_TABLE_HANDLER      Handler,
    660     void                    *Context)
    661 {
    662     ACPI_STATUS             Status;
    663 
    664 
    665     ACPI_FUNCTION_TRACE (AcpiInstallTableHandler);
    666 
    667 
    668     if (!Handler)
    669     {
    670         return_ACPI_STATUS (AE_BAD_PARAMETER);
    671     }
    672 
    673     Status = AcpiUtAcquireMutex (ACPI_MTX_EVENTS);
    674     if (ACPI_FAILURE (Status))
    675     {
    676         return_ACPI_STATUS (Status);
    677     }
    678 
    679     /* Don't allow more than one handler */
    680 
    681     if (AcpiGbl_TableHandler)
    682     {
    683         Status = AE_ALREADY_EXISTS;
    684         goto Cleanup;
    685     }
    686 
    687     /* Install the handler */
    688 
    689     AcpiGbl_TableHandler = Handler;
    690     AcpiGbl_TableHandlerContext = Context;
    691 
    692 Cleanup:
    693     (void) AcpiUtReleaseMutex (ACPI_MTX_EVENTS);
    694     return_ACPI_STATUS (Status);
    695 }
    696 
    697 ACPI_EXPORT_SYMBOL (AcpiInstallTableHandler)
    698 
    699 
    700 /*******************************************************************************
    701  *
    702  * FUNCTION:    AcpiRemoveTableHandler
    703  *
    704  * PARAMETERS:  Handler         - Table event handler that was installed
    705  *                                previously.
    706  *
    707  * RETURN:      Status
    708  *
    709  * DESCRIPTION: Remove a table event handler
    710  *
    711  ******************************************************************************/
    712 
    713 ACPI_STATUS
    714 AcpiRemoveTableHandler (
    715     ACPI_TABLE_HANDLER      Handler)
    716 {
    717     ACPI_STATUS             Status;
    718 
    719 
    720     ACPI_FUNCTION_TRACE (AcpiRemoveTableHandler);
    721 
    722 
    723     Status = AcpiUtAcquireMutex (ACPI_MTX_EVENTS);
    724     if (ACPI_FAILURE (Status))
    725     {
    726         return_ACPI_STATUS (Status);
    727     }
    728 
    729     /* Make sure that the installed handler is the same */
    730 
    731     if (!Handler ||
    732         Handler != AcpiGbl_TableHandler)
    733     {
    734         Status = AE_BAD_PARAMETER;
    735         goto Cleanup;
    736     }
    737 
    738     /* Remove the handler */
    739 
    740     AcpiGbl_TableHandler = NULL;
    741 
    742 Cleanup:
    743     (void) AcpiUtReleaseMutex (ACPI_MTX_EVENTS);
    744     return_ACPI_STATUS (Status);
    745 }
    746 
    747 ACPI_EXPORT_SYMBOL (AcpiRemoveTableHandler)
    748