xref: /freebsd/sys/contrib/dev/acpica/components/utilities/utosi.c (revision acb1f1269c6f4ff89a0d28ba742f6687e9ef779d)
1 /******************************************************************************
2  *
3  * Module Name: utosi - Support for the _OSI predefined control method
4  *
5  *****************************************************************************/
6 
7 /******************************************************************************
8  *
9  * 1. Copyright Notice
10  *
11  * Some or all of this work - Copyright (c) 1999 - 2021, 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 <contrib/dev/acpica/include/acpi.h>
153 #include <contrib/dev/acpica/include/accommon.h>
154 
155 
156 #define _COMPONENT          ACPI_UTILITIES
157         ACPI_MODULE_NAME    ("utosi")
158 
159 
160 /******************************************************************************
161  *
162  * ACPICA policy for new _OSI strings:
163  *
164  * It is the stated policy of ACPICA that new _OSI strings will be integrated
165  * into this module as soon as possible after they are defined. It is strongly
166  * recommended that all ACPICA hosts mirror this policy and integrate any
167  * changes to this module as soon as possible. There are several historical
168  * reasons behind this policy:
169  *
170  * 1) New BIOSs tend to test only the case where the host responds TRUE to
171  *    the latest version of Windows, which would respond to the latest/newest
172  *    _OSI string. Not responding TRUE to the latest version of Windows will
173  *    risk executing untested code paths throughout the DSDT and SSDTs.
174  *
175  * 2) If a new _OSI string is recognized only after a significant delay, this
176  *    has the potential to cause problems on existing working machines because
177  *    of the possibility that a new and different path through the ASL code
178  *    will be executed.
179  *
180  * 3) New _OSI strings are tending to come out about once per year. A delay
181  *    in recognizing a new string for a significant amount of time risks the
182  *    release of another string which only compounds the initial problem.
183  *
184  *****************************************************************************/
185 
186 
187 /*
188  * Strings supported by the _OSI predefined control method (which is
189  * implemented internally within this module.)
190  *
191  * March 2009: Removed "Linux" as this host no longer wants to respond true
192  * for this string. Basically, the only safe OS strings are windows-related
193  * and in many or most cases represent the only test path within the
194  * BIOS-provided ASL code.
195  *
196  * The last element of each entry is used to track the newest version of
197  * Windows that the BIOS has requested.
198  */
199 static ACPI_INTERFACE_INFO    AcpiDefaultSupportedInterfaces[] =
200 {
201     /* Operating System Vendor Strings */
202 
203     {"Windows 2000",        NULL, 0, ACPI_OSI_WIN_2000},         /* Windows 2000 */
204     {"Windows 2001",        NULL, 0, ACPI_OSI_WIN_XP},           /* Windows XP */
205     {"Windows 2001 SP1",    NULL, 0, ACPI_OSI_WIN_XP_SP1},       /* Windows XP SP1 */
206     {"Windows 2001.1",      NULL, 0, ACPI_OSI_WINSRV_2003},      /* Windows Server 2003 */
207     {"Windows 2001 SP2",    NULL, 0, ACPI_OSI_WIN_XP_SP2},       /* Windows XP SP2 */
208     {"Windows 2001.1 SP1",  NULL, 0, ACPI_OSI_WINSRV_2003_SP1},  /* Windows Server 2003 SP1 - Added 03/2006 */
209     {"Windows 2006",        NULL, 0, ACPI_OSI_WIN_VISTA},        /* Windows Vista - Added 03/2006 */
210     {"Windows 2006.1",      NULL, 0, ACPI_OSI_WINSRV_2008},      /* Windows Server 2008 - Added 09/2009 */
211     {"Windows 2006 SP1",    NULL, 0, ACPI_OSI_WIN_VISTA_SP1},    /* Windows Vista SP1 - Added 09/2009 */
212     {"Windows 2006 SP2",    NULL, 0, ACPI_OSI_WIN_VISTA_SP2},    /* Windows Vista SP2 - Added 09/2010 */
213     {"Windows 2009",        NULL, 0, ACPI_OSI_WIN_7},            /* Windows 7 and Server 2008 R2 - Added 09/2009 */
214     {"Windows 2012",        NULL, 0, ACPI_OSI_WIN_8},            /* Windows 8 and Server 2012 - Added 08/2012 */
215     {"Windows 2013",        NULL, 0, ACPI_OSI_WIN_8_1},          /* Windows 8.1 and Server 2012 R2 - Added 01/2014 */
216     {"Windows 2015",        NULL, 0, ACPI_OSI_WIN_10},           /* Windows 10 - Added 03/2015 */
217     {"Windows 2016",        NULL, 0, ACPI_OSI_WIN_10_RS1},       /* Windows 10 version 1607 - Added 12/2017 */
218     {"Windows 2017",        NULL, 0, ACPI_OSI_WIN_10_RS2},       /* Windows 10 version 1703 - Added 12/2017 */
219     {"Windows 2017.2",      NULL, 0, ACPI_OSI_WIN_10_RS3},       /* Windows 10 version 1709 - Added 02/2018 */
220     {"Windows 2018",        NULL, 0, ACPI_OSI_WIN_10_RS4},       /* Windows 10 version 1803 - Added 11/2018 */
221     {"Windows 2018.2",      NULL, 0, ACPI_OSI_WIN_10_RS5},       /* Windows 10 version 1809 - Added 11/2018 */
222     {"Windows 2019",        NULL, 0, ACPI_OSI_WIN_10_19H1},      /* Windows 10 version 1903 - Added 08/2019 */
223 
224     /* Feature Group Strings */
225 
226     {"Extended Address Space Descriptor", NULL, ACPI_OSI_FEATURE, 0},
227 
228     /*
229      * All "optional" feature group strings (features that are implemented
230      * by the host) should be dynamically modified to VALID by the host via
231      * AcpiInstallInterface or AcpiUpdateInterfaces. Such optional feature
232      * group strings are set as INVALID by default here.
233      */
234 
235     {"Module Device",               NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
236     {"Processor Device",            NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
237     {"3.0 Thermal Model",           NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
238     {"3.0 _SCP Extensions",         NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
239     {"Processor Aggregator Device", NULL, ACPI_OSI_OPTIONAL_FEATURE, 0}
240 };
241 
242 
243 /*******************************************************************************
244  *
245  * FUNCTION:    AcpiUtInitializeInterfaces
246  *
247  * PARAMETERS:  None
248  *
249  * RETURN:      Status
250  *
251  * DESCRIPTION: Initialize the global _OSI supported interfaces list
252  *
253  ******************************************************************************/
254 
255 ACPI_STATUS
256 AcpiUtInitializeInterfaces (
257     void)
258 {
259     ACPI_STATUS             Status;
260     UINT32                  i;
261 
262 
263     Status = AcpiOsAcquireMutex (AcpiGbl_OsiMutex, ACPI_WAIT_FOREVER);
264     if (ACPI_FAILURE (Status))
265     {
266         return (Status);
267     }
268 
269     AcpiGbl_SupportedInterfaces = AcpiDefaultSupportedInterfaces;
270 
271     /* Link the static list of supported interfaces */
272 
273     for (i = 0;
274         i < (ACPI_ARRAY_LENGTH (AcpiDefaultSupportedInterfaces) - 1);
275         i++)
276     {
277         AcpiDefaultSupportedInterfaces[i].Next =
278             &AcpiDefaultSupportedInterfaces[(ACPI_SIZE) i + 1];
279     }
280 
281     AcpiOsReleaseMutex (AcpiGbl_OsiMutex);
282     return (AE_OK);
283 }
284 
285 
286 /*******************************************************************************
287  *
288  * FUNCTION:    AcpiUtInterfaceTerminate
289  *
290  * PARAMETERS:  None
291  *
292  * RETURN:      Status
293  *
294  * DESCRIPTION: Delete all interfaces in the global list. Sets
295  *              AcpiGbl_SupportedInterfaces to NULL.
296  *
297  ******************************************************************************/
298 
299 ACPI_STATUS
300 AcpiUtInterfaceTerminate (
301     void)
302 {
303     ACPI_STATUS             Status;
304     ACPI_INTERFACE_INFO     *NextInterface;
305 
306 
307     Status = AcpiOsAcquireMutex (AcpiGbl_OsiMutex, ACPI_WAIT_FOREVER);
308     if (ACPI_FAILURE (Status))
309     {
310         return (Status);
311     }
312 
313     NextInterface = AcpiGbl_SupportedInterfaces;
314     while (NextInterface)
315     {
316         AcpiGbl_SupportedInterfaces = NextInterface->Next;
317 
318         if (NextInterface->Flags & ACPI_OSI_DYNAMIC)
319         {
320             /* Only interfaces added at runtime can be freed */
321 
322             ACPI_FREE (NextInterface->Name);
323             ACPI_FREE (NextInterface);
324         }
325         else
326         {
327             /* Interface is in static list. Reset it to invalid or valid. */
328 
329             if (NextInterface->Flags & ACPI_OSI_DEFAULT_INVALID)
330             {
331                 NextInterface->Flags |= ACPI_OSI_INVALID;
332             }
333             else
334             {
335                 NextInterface->Flags &= ~ACPI_OSI_INVALID;
336             }
337         }
338 
339         NextInterface = AcpiGbl_SupportedInterfaces;
340     }
341 
342     AcpiOsReleaseMutex (AcpiGbl_OsiMutex);
343     return (AE_OK);
344 }
345 
346 
347 /*******************************************************************************
348  *
349  * FUNCTION:    AcpiUtInstallInterface
350  *
351  * PARAMETERS:  InterfaceName       - The interface to install
352  *
353  * RETURN:      Status
354  *
355  * DESCRIPTION: Install the interface into the global interface list.
356  *              Caller MUST hold AcpiGbl_OsiMutex
357  *
358  ******************************************************************************/
359 
360 ACPI_STATUS
361 AcpiUtInstallInterface (
362     ACPI_STRING             InterfaceName)
363 {
364     ACPI_INTERFACE_INFO     *InterfaceInfo;
365 
366 
367     /* Allocate info block and space for the name string */
368 
369     InterfaceInfo = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_INTERFACE_INFO));
370     if (!InterfaceInfo)
371     {
372         return (AE_NO_MEMORY);
373     }
374 
375     InterfaceInfo->Name = ACPI_ALLOCATE_ZEROED (strlen (InterfaceName) + 1);
376     if (!InterfaceInfo->Name)
377     {
378         ACPI_FREE (InterfaceInfo);
379         return (AE_NO_MEMORY);
380     }
381 
382     /* Initialize new info and insert at the head of the global list */
383 
384     strcpy (InterfaceInfo->Name, InterfaceName);
385     InterfaceInfo->Flags = ACPI_OSI_DYNAMIC;
386     InterfaceInfo->Next = AcpiGbl_SupportedInterfaces;
387 
388     AcpiGbl_SupportedInterfaces = InterfaceInfo;
389     return (AE_OK);
390 }
391 
392 
393 /*******************************************************************************
394  *
395  * FUNCTION:    AcpiUtRemoveInterface
396  *
397  * PARAMETERS:  InterfaceName       - The interface to remove
398  *
399  * RETURN:      Status
400  *
401  * DESCRIPTION: Remove the interface from the global interface list.
402  *              Caller MUST hold AcpiGbl_OsiMutex
403  *
404  ******************************************************************************/
405 
406 ACPI_STATUS
407 AcpiUtRemoveInterface (
408     ACPI_STRING             InterfaceName)
409 {
410     ACPI_INTERFACE_INFO     *PreviousInterface;
411     ACPI_INTERFACE_INFO     *NextInterface;
412 
413 
414     PreviousInterface = NextInterface = AcpiGbl_SupportedInterfaces;
415     while (NextInterface)
416     {
417         if (!strcmp (InterfaceName, NextInterface->Name))
418         {
419             /*
420              * Found: name is in either the static list
421              * or was added at runtime
422              */
423             if (NextInterface->Flags & ACPI_OSI_DYNAMIC)
424             {
425                 /* Interface was added dynamically, remove and free it */
426 
427                 if (PreviousInterface == NextInterface)
428                 {
429                     AcpiGbl_SupportedInterfaces = NextInterface->Next;
430                 }
431                 else
432                 {
433                     PreviousInterface->Next = NextInterface->Next;
434                 }
435 
436                 ACPI_FREE (NextInterface->Name);
437                 ACPI_FREE (NextInterface);
438             }
439             else
440             {
441                 /*
442                  * Interface is in static list. If marked invalid, then
443                  * it does not actually exist. Else, mark it invalid.
444                  */
445                 if (NextInterface->Flags & ACPI_OSI_INVALID)
446                 {
447                     return (AE_NOT_EXIST);
448                 }
449 
450                 NextInterface->Flags |= ACPI_OSI_INVALID;
451             }
452 
453             return (AE_OK);
454         }
455 
456         PreviousInterface = NextInterface;
457         NextInterface = NextInterface->Next;
458     }
459 
460     /* Interface was not found */
461 
462     return (AE_NOT_EXIST);
463 }
464 
465 
466 /*******************************************************************************
467  *
468  * FUNCTION:    AcpiUtUpdateInterfaces
469  *
470  * PARAMETERS:  Action              - Actions to be performed during the
471  *                                    update
472  *
473  * RETURN:      Status
474  *
475  * DESCRIPTION: Update _OSI interface strings, disabling or enabling OS vendor
476  *              strings or/and feature group strings.
477  *              Caller MUST hold AcpiGbl_OsiMutex
478  *
479  ******************************************************************************/
480 
481 ACPI_STATUS
482 AcpiUtUpdateInterfaces (
483     UINT8                   Action)
484 {
485     ACPI_INTERFACE_INFO     *NextInterface;
486 
487 
488     NextInterface = AcpiGbl_SupportedInterfaces;
489     while (NextInterface)
490     {
491         if (((NextInterface->Flags & ACPI_OSI_FEATURE) &&
492              (Action & ACPI_FEATURE_STRINGS)) ||
493             (!(NextInterface->Flags & ACPI_OSI_FEATURE) &&
494              (Action & ACPI_VENDOR_STRINGS)))
495         {
496             if (Action & ACPI_DISABLE_INTERFACES)
497             {
498                 /* Mark the interfaces as invalid */
499 
500                 NextInterface->Flags |= ACPI_OSI_INVALID;
501             }
502             else
503             {
504                 /* Mark the interfaces as valid */
505 
506                 NextInterface->Flags &= ~ACPI_OSI_INVALID;
507             }
508         }
509 
510         NextInterface = NextInterface->Next;
511     }
512 
513     return (AE_OK);
514 }
515 
516 
517 /*******************************************************************************
518  *
519  * FUNCTION:    AcpiUtGetInterface
520  *
521  * PARAMETERS:  InterfaceName       - The interface to find
522  *
523  * RETURN:      ACPI_INTERFACE_INFO if found. NULL if not found.
524  *
525  * DESCRIPTION: Search for the specified interface name in the global list.
526  *              Caller MUST hold AcpiGbl_OsiMutex
527  *
528  ******************************************************************************/
529 
530 ACPI_INTERFACE_INFO *
531 AcpiUtGetInterface (
532     ACPI_STRING             InterfaceName)
533 {
534     ACPI_INTERFACE_INFO     *NextInterface;
535 
536 
537     NextInterface = AcpiGbl_SupportedInterfaces;
538     while (NextInterface)
539     {
540         if (!strcmp (InterfaceName, NextInterface->Name))
541         {
542             return (NextInterface);
543         }
544 
545         NextInterface = NextInterface->Next;
546     }
547 
548     return (NULL);
549 }
550 
551 
552 /*******************************************************************************
553  *
554  * FUNCTION:    AcpiUtOsiImplementation
555  *
556  * PARAMETERS:  WalkState           - Current walk state
557  *
558  * RETURN:      Status
559  *              Integer: TRUE (0) if input string is matched
560  *                       FALSE (-1) if string is not matched
561  *
562  * DESCRIPTION: Implementation of the _OSI predefined control method. When
563  *              an invocation of _OSI is encountered in the system AML,
564  *              control is transferred to this function.
565  *
566  * (August 2016)
567  * Note:  _OSI is now defined to return "Ones" to indicate a match, for
568  * compatibility with other ACPI implementations. On a 32-bit DSDT, Ones
569  * is 0xFFFFFFFF. On a 64-bit DSDT, Ones is 0xFFFFFFFFFFFFFFFF
570  * (ACPI_UINT64_MAX).
571  *
572  * This function always returns ACPI_UINT64_MAX for TRUE, and later code
573  * will truncate this to 32 bits if necessary.
574  *
575  ******************************************************************************/
576 
577 ACPI_STATUS
578 AcpiUtOsiImplementation (
579     ACPI_WALK_STATE         *WalkState)
580 {
581     ACPI_OPERAND_OBJECT     *StringDesc;
582     ACPI_OPERAND_OBJECT     *ReturnDesc;
583     ACPI_INTERFACE_INFO     *InterfaceInfo;
584     ACPI_INTERFACE_HANDLER  InterfaceHandler;
585     ACPI_STATUS             Status;
586     UINT64                  ReturnValue;
587 
588 
589     ACPI_FUNCTION_TRACE (UtOsiImplementation);
590 
591 
592     /* Validate the string input argument (from the AML caller) */
593 
594     StringDesc = WalkState->Arguments[0].Object;
595     if (!StringDesc ||
596         (StringDesc->Common.Type != ACPI_TYPE_STRING))
597     {
598         return_ACPI_STATUS (AE_TYPE);
599     }
600 
601     /* Create a return object */
602 
603     ReturnDesc = AcpiUtCreateInternalObject (ACPI_TYPE_INTEGER);
604     if (!ReturnDesc)
605     {
606         return_ACPI_STATUS (AE_NO_MEMORY);
607     }
608 
609     /* Default return value is 0, NOT SUPPORTED */
610 
611     ReturnValue = 0;
612     Status = AcpiOsAcquireMutex (AcpiGbl_OsiMutex, ACPI_WAIT_FOREVER);
613     if (ACPI_FAILURE (Status))
614     {
615         AcpiUtRemoveReference (ReturnDesc);
616         return_ACPI_STATUS (Status);
617     }
618 
619     /* Lookup the interface in the global _OSI list */
620 
621     InterfaceInfo = AcpiUtGetInterface (StringDesc->String.Pointer);
622     if (InterfaceInfo &&
623         !(InterfaceInfo->Flags & ACPI_OSI_INVALID))
624     {
625         /*
626          * The interface is supported.
627          * Update the OsiData if necessary. We keep track of the latest
628          * version of Windows that has been requested by the BIOS.
629          */
630         if (InterfaceInfo->Value > AcpiGbl_OsiData)
631         {
632             AcpiGbl_OsiData = InterfaceInfo->Value;
633         }
634 
635         ReturnValue = ACPI_UINT64_MAX;
636     }
637 
638     AcpiOsReleaseMutex (AcpiGbl_OsiMutex);
639 
640     /*
641      * Invoke an optional _OSI interface handler. The host OS may wish
642      * to do some interface-specific handling. For example, warn about
643      * certain interfaces or override the true/false support value.
644      */
645     InterfaceHandler = AcpiGbl_InterfaceHandler;
646     if (InterfaceHandler)
647     {
648         if (InterfaceHandler (
649             StringDesc->String.Pointer, (UINT32) ReturnValue))
650         {
651             ReturnValue = ACPI_UINT64_MAX;
652         }
653     }
654 
655     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INFO,
656         "ACPI: BIOS _OSI(\"%s\") is %ssupported\n",
657         StringDesc->String.Pointer, ReturnValue == 0 ? "not " : ""));
658 
659     /* Complete the return object */
660 
661     ReturnDesc->Integer.Value = ReturnValue;
662     WalkState->ReturnDesc = ReturnDesc;
663     return_ACPI_STATUS (AE_OK);
664 }
665