LXR 6.1/​bsps/​shared/​acpi/​acpica/​utilities/​utosi.c	Source navigation Diff markup Identifier search General search
	Version: 6.1 Revert   Change

File indexing completed on 2025-05-11 08:24:03

 /******************************************************************************
  *
  * Module Name: utosi - Support for the _OSI predefined control method
  *
  *****************************************************************************/
 
 /******************************************************************************
  *
  * 1. Copyright Notice
  *
  * Some or all of this work - Copyright (c) 1999 - 2024, Intel Corp.
  * All rights reserved.
  *
  * 2. License
  *
  * 2.1. This is your license from Intel Corp. under its intellectual property
  * rights. You may have additional license terms from the party that provided
  * you this software, covering your right to use that party's intellectual
  * property rights.
  *
  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
  * copy of the source code appearing in this file ("Covered Code") an
  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
  * base code distributed originally by Intel ("Original Intel Code") to copy,
  * make derivatives, distribute, use and display any portion of the Covered
  * Code in any form, with the right to sublicense such rights; and
  *
  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
  * license (with the right to sublicense), under only those claims of Intel
  * patents that are infringed by the Original Intel Code, to make, use, sell,
  * offer to sell, and import the Covered Code and derivative works thereof
  * solely to the minimum extent necessary to exercise the above copyright
  * license, and in no event shall the patent license extend to any additions
  * to or modifications of the Original Intel Code. No other license or right
  * is granted directly or by implication, estoppel or otherwise;
  *
  * The above copyright and patent license is granted only if the following
  * conditions are met:
  *
  * 3. Conditions
  *
  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
  * Redistribution of source code of any substantial portion of the Covered
  * Code or modification with rights to further distribute source must include
  * the above Copyright Notice, the above License, this list of Conditions,
  * and the following Disclaimer and Export Compliance provision. In addition,
  * Licensee must cause all Covered Code to which Licensee contributes to
  * contain a file documenting the changes Licensee made to create that Covered
  * Code and the date of any change. Licensee must include in that file the
  * documentation of any changes made by any predecessor Licensee. Licensee
  * must include a prominent statement that the modification is derived,
  * directly or indirectly, from Original Intel Code.
  *
  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
  * Redistribution of source code of any substantial portion of the Covered
  * Code or modification without rights to further distribute source must
  * include the following Disclaimer and Export Compliance provision in the
  * documentation and/or other materials provided with distribution. In
  * addition, Licensee may not authorize further sublicense of source of any
  * portion of the Covered Code, and must include terms to the effect that the
  * license from Licensee to its licensee is limited to the intellectual
  * property embodied in the software Licensee provides to its licensee, and
  * not to intellectual property embodied in modifications its licensee may
  * make.
  *
  * 3.3. Redistribution of Executable. Redistribution in executable form of any
  * substantial portion of the Covered Code or modification must reproduce the
  * above Copyright Notice, and the following Disclaimer and Export Compliance
  * provision in the documentation and/or other materials provided with the
  * distribution.
  *
  * 3.4. Intel retains all right, title, and interest in and to the Original
  * Intel Code.
  *
  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
  * Intel shall be used in advertising or otherwise to promote the sale, use or
  * other dealings in products derived from or relating to the Covered Code
  * without prior written authorization from Intel.
  *
  * 4. Disclaimer and Export Compliance
  *
  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
  * PARTICULAR PURPOSE.
  *
  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
  * LIMITED REMEDY.
  *
  * 4.3. Licensee shall not export, either directly or indirectly, any of this
  * software or system incorporating such software without first obtaining any
  * required license or other approval from the U. S. Department of Commerce or
  * any other agency or department of the United States Government. In the
  * event Licensee exports any such software from the United States or
  * re-exports any such software from a foreign destination, Licensee shall
  * ensure that the distribution and export/re-export of the software is in
  * compliance with all laws, regulations, orders, or other restrictions of the
  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
  * any of its subsidiaries will export/re-export any technical data, process,
  * software, or service, directly or indirectly, to any country for which the
  * United States government or any agency thereof requires an export license,
  * other governmental approval, or letter of assurance, without first obtaining
  * such license, approval or letter.
  *
  *****************************************************************************
  *
  * Alternatively, you may choose to be licensed under the terms of the
  * following license:
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions, and the following disclaimer,
  *    without modification.
  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  *    substantially similar to the "NO WARRANTY" disclaimer below
  *    ("Disclaimer") and any redistribution must be conditioned upon
  *    including a substantially similar Disclaimer requirement for further
  *    binary redistribution.
  * 3. Neither the names of the above-listed copyright holders nor the names
  *    of any contributors may be used to endorse or promote products derived
  *    from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  * Alternatively, you may choose to be licensed under the terms of the
  * GNU General Public License ("GPL") version 2 as published by the Free
  * Software Foundation.
  *
  *****************************************************************************/
 
 #include "acpi.h"
 #include "accommon.h"
 
 
 #define _COMPONENT          ACPI_UTILITIES
         ACPI_MODULE_NAME    ("utosi")
 
 
 /******************************************************************************
  *
  * ACPICA policy for new _OSI strings:
  *
  * It is the stated policy of ACPICA that new _OSI strings will be integrated
  * into this module as soon as possible after they are defined. It is strongly
  * recommended that all ACPICA hosts mirror this policy and integrate any
  * changes to this module as soon as possible. There are several historical
  * reasons behind this policy:
  *
  * 1) New BIOSs tend to test only the case where the host responds TRUE to
  *    the latest version of Windows, which would respond to the latest/newest
  *    _OSI string. Not responding TRUE to the latest version of Windows will
  *    risk executing untested code paths throughout the DSDT and SSDTs.
  *
  * 2) If a new _OSI string is recognized only after a significant delay, this
  *    has the potential to cause problems on existing working machines because
  *    of the possibility that a new and different path through the ASL code
  *    will be executed.
  *
  * 3) New _OSI strings are tending to come out about once per year. A delay
  *    in recognizing a new string for a significant amount of time risks the
  *    release of another string which only compounds the initial problem.
  *
  *****************************************************************************/
 
 
 /*
  * Strings supported by the _OSI predefined control method (which is
  * implemented internally within this module.)
  *
  * March 2009: Removed "Linux" as this host no longer wants to respond true
  * for this string. Basically, the only safe OS strings are windows-related
  * and in many or most cases represent the only test path within the
  * BIOS-provided ASL code.
  *
  * The last element of each entry is used to track the newest version of
  * Windows that the BIOS has requested.
  */
 static ACPI_INTERFACE_INFO    AcpiDefaultSupportedInterfaces[] =
 {
     /* Operating System Vendor Strings */
 
     {"Windows 2000",        NULL, 0, ACPI_OSI_WIN_2000},         /* Windows 2000 */
     {"Windows 2001",        NULL, 0, ACPI_OSI_WIN_XP},           /* Windows XP */
     {"Windows 2001 SP1",    NULL, 0, ACPI_OSI_WIN_XP_SP1},       /* Windows XP SP1 */
     {"Windows 2001.1",      NULL, 0, ACPI_OSI_WINSRV_2003},      /* Windows Server 2003 */
     {"Windows 2001 SP2",    NULL, 0, ACPI_OSI_WIN_XP_SP2},       /* Windows XP SP2 */
     {"Windows 2001.1 SP1",  NULL, 0, ACPI_OSI_WINSRV_2003_SP1},  /* Windows Server 2003 SP1 - Added 03/2006 */
     {"Windows 2006",        NULL, 0, ACPI_OSI_WIN_VISTA},        /* Windows Vista - Added 03/2006 */
     {"Windows 2006.1",      NULL, 0, ACPI_OSI_WINSRV_2008},      /* Windows Server 2008 - Added 09/2009 */
     {"Windows 2006 SP1",    NULL, 0, ACPI_OSI_WIN_VISTA_SP1},    /* Windows Vista SP1 - Added 09/2009 */
     {"Windows 2006 SP2",    NULL, 0, ACPI_OSI_WIN_VISTA_SP2},    /* Windows Vista SP2 - Added 09/2010 */
     {"Windows 2009",        NULL, 0, ACPI_OSI_WIN_7},            /* Windows 7 and Server 2008 R2 - Added 09/2009 */
     {"Windows 2012",        NULL, 0, ACPI_OSI_WIN_8},            /* Windows 8 and Server 2012 - Added 08/2012 */
     {"Windows 2013",        NULL, 0, ACPI_OSI_WIN_8_1},          /* Windows 8.1 and Server 2012 R2 - Added 01/2014 */
     {"Windows 2015",        NULL, 0, ACPI_OSI_WIN_10},           /* Windows 10 - Added 03/2015 */
     {"Windows 2016",        NULL, 0, ACPI_OSI_WIN_10_RS1},       /* Windows 10 version 1607 - Added 12/2017 */
     {"Windows 2017",        NULL, 0, ACPI_OSI_WIN_10_RS2},       /* Windows 10 version 1703 - Added 12/2017 */
     {"Windows 2017.2",      NULL, 0, ACPI_OSI_WIN_10_RS3},       /* Windows 10 version 1709 - Added 02/2018 */
     {"Windows 2018",        NULL, 0, ACPI_OSI_WIN_10_RS4},       /* Windows 10 version 1803 - Added 11/2018 */
     {"Windows 2018.2",      NULL, 0, ACPI_OSI_WIN_10_RS5},       /* Windows 10 version 1809 - Added 11/2018 */
     {"Windows 2019",        NULL, 0, ACPI_OSI_WIN_10_19H1},      /* Windows 10 version 1903 - Added 08/2019 */
     {"Windows 2020",        NULL, 0, ACPI_OSI_WIN_10_20H1},      /* Windows 10 version 2004 - Added 08/2021 */
     {"Windows 2021",        NULL, 0, ACPI_OSI_WIN_11},           /* Windows 11 - Added 01/2022 */
     {"Windows 2022",        NULL, 0, ACPI_OSI_WIN_11_22H2},      /* Windows 11 version 22H2 - Added 04/2024 */
 
     /* Feature Group Strings */
 
     {"Extended Address Space Descriptor", NULL, ACPI_OSI_FEATURE, 0},
 
     /*
      * All "optional" feature group strings (features that are implemented
      * by the host) should be dynamically modified to VALID by the host via
      * AcpiInstallInterface or AcpiUpdateInterfaces. Such optional feature
      * group strings are set as INVALID by default here.
      */
 
     {"Module Device",               NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
     {"Processor Device",            NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
     {"3.0 Thermal Model",           NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
     {"3.0 _SCP Extensions",         NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
     {"Processor Aggregator Device", NULL, ACPI_OSI_OPTIONAL_FEATURE, 0}
 };
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiUtInitializeInterfaces
  *
  * PARAMETERS:  None
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Initialize the global _OSI supported interfaces list
  *
  ******************************************************************************/
 
 ACPI_STATUS
 AcpiUtInitializeInterfaces (
     void)
 {
     ACPI_STATUS             Status;
     UINT32                  i;
 
 
     Status = AcpiOsAcquireMutex (AcpiGbl_OsiMutex, ACPI_WAIT_FOREVER);
     if (ACPI_FAILURE (Status))
     {
         return (Status);
     }
 
     AcpiGbl_SupportedInterfaces = AcpiDefaultSupportedInterfaces;
 
     /* Link the static list of supported interfaces */
 
     for (i = 0;
         i < (ACPI_ARRAY_LENGTH (AcpiDefaultSupportedInterfaces) - 1);
         i++)
     {
         AcpiDefaultSupportedInterfaces[i].Next =
             &AcpiDefaultSupportedInterfaces[(ACPI_SIZE) i + 1];
     }
 
     AcpiOsReleaseMutex (AcpiGbl_OsiMutex);
     return (AE_OK);
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiUtInterfaceTerminate
  *
  * PARAMETERS:  None
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Delete all interfaces in the global list. Sets
  *              AcpiGbl_SupportedInterfaces to NULL.
  *
  ******************************************************************************/
 
 ACPI_STATUS
 AcpiUtInterfaceTerminate (
     void)
 {
     ACPI_STATUS             Status;
     ACPI_INTERFACE_INFO     *NextInterface;
 
 
     Status = AcpiOsAcquireMutex (AcpiGbl_OsiMutex, ACPI_WAIT_FOREVER);
     if (ACPI_FAILURE (Status))
     {
         return (Status);
     }
 
     NextInterface = AcpiGbl_SupportedInterfaces;
     while (NextInterface)
     {
         AcpiGbl_SupportedInterfaces = NextInterface->Next;
 
         if (NextInterface->Flags & ACPI_OSI_DYNAMIC)
         {
             /* Only interfaces added at runtime can be freed */
 
             ACPI_FREE (NextInterface->Name);
             ACPI_FREE (NextInterface);
         }
         else
         {
             /* Interface is in static list. Reset it to invalid or valid. */
 
             if (NextInterface->Flags & ACPI_OSI_DEFAULT_INVALID)
             {
                 NextInterface->Flags |= ACPI_OSI_INVALID;
             }
             else
             {
                 NextInterface->Flags &= ~ACPI_OSI_INVALID;
             }
         }
 
         NextInterface = AcpiGbl_SupportedInterfaces;
     }
 
     AcpiOsReleaseMutex (AcpiGbl_OsiMutex);
     return (AE_OK);
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiUtInstallInterface
  *
  * PARAMETERS:  InterfaceName       - The interface to install
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Install the interface into the global interface list.
  *              Caller MUST hold AcpiGbl_OsiMutex
  *
  ******************************************************************************/
 
 ACPI_STATUS
 AcpiUtInstallInterface (
     ACPI_STRING             InterfaceName)
 {
     ACPI_INTERFACE_INFO     *InterfaceInfo;
 
 
     /* Allocate info block and space for the name string */
 
     InterfaceInfo = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_INTERFACE_INFO));
     if (!InterfaceInfo)
     {
         return (AE_NO_MEMORY);
     }
 
     InterfaceInfo->Name = ACPI_ALLOCATE_ZEROED (strlen (InterfaceName) + 1);
     if (!InterfaceInfo->Name)
     {
         ACPI_FREE (InterfaceInfo);
         return (AE_NO_MEMORY);
     }
 
     /* Initialize new info and insert at the head of the global list */
 
     strcpy (InterfaceInfo->Name, InterfaceName);
     InterfaceInfo->Flags = ACPI_OSI_DYNAMIC;
     InterfaceInfo->Next = AcpiGbl_SupportedInterfaces;
 
     AcpiGbl_SupportedInterfaces = InterfaceInfo;
     return (AE_OK);
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiUtRemoveInterface
  *
  * PARAMETERS:  InterfaceName       - The interface to remove
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Remove the interface from the global interface list.
  *              Caller MUST hold AcpiGbl_OsiMutex
  *
  ******************************************************************************/
 
 ACPI_STATUS
 AcpiUtRemoveInterface (
     ACPI_STRING             InterfaceName)
 {
     ACPI_INTERFACE_INFO     *PreviousInterface;
     ACPI_INTERFACE_INFO     *NextInterface;
 
 
     PreviousInterface = NextInterface = AcpiGbl_SupportedInterfaces;
     while (NextInterface)
     {
         if (!strcmp (InterfaceName, NextInterface->Name))
         {
             /*
              * Found: name is in either the static list
              * or was added at runtime
              */
             if (NextInterface->Flags & ACPI_OSI_DYNAMIC)
             {
                 /* Interface was added dynamically, remove and free it */
 
                 if (PreviousInterface == NextInterface)
                 {
                     AcpiGbl_SupportedInterfaces = NextInterface->Next;
                 }
                 else
                 {
                     PreviousInterface->Next = NextInterface->Next;
                 }
 
                 ACPI_FREE (NextInterface->Name);
                 ACPI_FREE (NextInterface);
             }
             else
             {
                 /*
                  * Interface is in static list. If marked invalid, then
                  * it does not actually exist. Else, mark it invalid.
                  */
                 if (NextInterface->Flags & ACPI_OSI_INVALID)
                 {
                     return (AE_NOT_EXIST);
                 }
 
                 NextInterface->Flags |= ACPI_OSI_INVALID;
             }
 
             return (AE_OK);
         }
 
         PreviousInterface = NextInterface;
         NextInterface = NextInterface->Next;
     }
 
     /* Interface was not found */
 
     return (AE_NOT_EXIST);
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiUtUpdateInterfaces
  *
  * PARAMETERS:  Action              - Actions to be performed during the
  *                                    update
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Update _OSI interface strings, disabling or enabling OS vendor
  *              strings or/and feature group strings.
  *              Caller MUST hold AcpiGbl_OsiMutex
  *
  ******************************************************************************/
 
 ACPI_STATUS
 AcpiUtUpdateInterfaces (
     UINT8                   Action)
 {
     ACPI_INTERFACE_INFO     *NextInterface;
 
 
     NextInterface = AcpiGbl_SupportedInterfaces;
     while (NextInterface)
     {
         if (((NextInterface->Flags & ACPI_OSI_FEATURE) &&
              (Action & ACPI_FEATURE_STRINGS)) ||
             (!(NextInterface->Flags & ACPI_OSI_FEATURE) &&
              (Action & ACPI_VENDOR_STRINGS)))
         {
             if (Action & ACPI_DISABLE_INTERFACES)
             {
                 /* Mark the interfaces as invalid */
 
                 NextInterface->Flags |= ACPI_OSI_INVALID;
             }
             else
             {
                 /* Mark the interfaces as valid */
 
                 NextInterface->Flags &= ~ACPI_OSI_INVALID;
             }
         }
 
         NextInterface = NextInterface->Next;
     }
 
     return (AE_OK);
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiUtGetInterface
  *
  * PARAMETERS:  InterfaceName       - The interface to find
  *
  * RETURN:      ACPI_INTERFACE_INFO if found. NULL if not found.
  *
  * DESCRIPTION: Search for the specified interface name in the global list.
  *              Caller MUST hold AcpiGbl_OsiMutex
  *
  ******************************************************************************/
 
 ACPI_INTERFACE_INFO *
 AcpiUtGetInterface (
     ACPI_STRING             InterfaceName)
 {
     ACPI_INTERFACE_INFO     *NextInterface;
 
 
     NextInterface = AcpiGbl_SupportedInterfaces;
     while (NextInterface)
     {
         if (!strcmp (InterfaceName, NextInterface->Name))
         {
             return (NextInterface);
         }
 
         NextInterface = NextInterface->Next;
     }
 
     return (NULL);
 }
 
 
 /*******************************************************************************
  *
  * FUNCTION:    AcpiUtOsiImplementation
  *
  * PARAMETERS:  WalkState           - Current walk state
  *
  * RETURN:      Status
  *              Integer: TRUE (0) if input string is matched
  *                       FALSE (-1) if string is not matched
  *
  * DESCRIPTION: Implementation of the _OSI predefined control method. When
  *              an invocation of _OSI is encountered in the system AML,
  *              control is transferred to this function.
  *
  * (August 2016)
  * Note:  _OSI is now defined to return "Ones" to indicate a match, for
  * compatibility with other ACPI implementations. On a 32-bit DSDT, Ones
  * is 0xFFFFFFFF. On a 64-bit DSDT, Ones is 0xFFFFFFFFFFFFFFFF
  * (ACPI_UINT64_MAX).
  *
  * This function always returns ACPI_UINT64_MAX for TRUE, and later code
  * will truncate this to 32 bits if necessary.
  *
  ******************************************************************************/
 
 ACPI_STATUS
 AcpiUtOsiImplementation (
     ACPI_WALK_STATE         *WalkState)
 {
     ACPI_OPERAND_OBJECT     *StringDesc;
     ACPI_OPERAND_OBJECT     *ReturnDesc;
     ACPI_INTERFACE_INFO     *InterfaceInfo;
     ACPI_INTERFACE_HANDLER  InterfaceHandler;
     ACPI_STATUS             Status;
     UINT64                  ReturnValue;
 
 
     ACPI_FUNCTION_TRACE (UtOsiImplementation);
 
 
     /* Validate the string input argument (from the AML caller) */
 
     StringDesc = WalkState->Arguments[0].Object;
     if (!StringDesc ||
         (StringDesc->Common.Type != ACPI_TYPE_STRING))
     {
         return_ACPI_STATUS (AE_TYPE);
     }
 
     /* Create a return object */
 
     ReturnDesc = AcpiUtCreateInternalObject (ACPI_TYPE_INTEGER);
     if (!ReturnDesc)
     {
         return_ACPI_STATUS (AE_NO_MEMORY);
     }
 
     /* Default return value is 0, NOT SUPPORTED */
 
     ReturnValue = 0;
     Status = AcpiOsAcquireMutex (AcpiGbl_OsiMutex, ACPI_WAIT_FOREVER);
     if (ACPI_FAILURE (Status))
     {
         AcpiUtRemoveReference (ReturnDesc);
         return_ACPI_STATUS (Status);
     }
 
     /* Lookup the interface in the global _OSI list */
 
     InterfaceInfo = AcpiUtGetInterface (StringDesc->String.Pointer);
     if (InterfaceInfo &&
         !(InterfaceInfo->Flags & ACPI_OSI_INVALID))
     {
         /*
          * The interface is supported.
          * Update the OsiData if necessary. We keep track of the latest
          * version of Windows that has been requested by the BIOS.
          */
         if (InterfaceInfo->Value > AcpiGbl_OsiData)
         {
             AcpiGbl_OsiData = InterfaceInfo->Value;
         }
 
         ReturnValue = ACPI_UINT64_MAX;
     }
 
     AcpiOsReleaseMutex (AcpiGbl_OsiMutex);
 
     /*
      * Invoke an optional _OSI interface handler. The host OS may wish
      * to do some interface-specific handling. For example, warn about
      * certain interfaces or override the true/false support value.
      */
     InterfaceHandler = AcpiGbl_InterfaceHandler;
     if (InterfaceHandler)
     {
         if (InterfaceHandler (
             StringDesc->String.Pointer, (UINT32) ReturnValue))
         {
             ReturnValue = ACPI_UINT64_MAX;
         }
     }
 
     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INFO,
         "ACPI: BIOS _OSI(\"%s\") is %ssupported\n",
         StringDesc->String.Pointer, ReturnValue == 0 ? "not " : ""));
 
     /* Complete the return object */
 
     ReturnDesc->Integer.Value = ReturnValue;
     WalkState->ReturnDesc = ReturnDesc;
     return_ACPI_STATUS (AE_OK);
 }

This page was automatically generated by the 2.3.7 LXR engine. The LXR team