xref: /freebsd/sys/contrib/dev/acpica/components/utilities/utosi.c (revision 105fd928b0b5b35ab529e5f6914788dc49582901)
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     {"Windows 2020",        NULL, 0, ACPI_OSI_WIN_10_20H1},      /* Windows 10 version 2004 - Added 08/2021 */
224 
225     /* Feature Group Strings */
226 
227     {"Extended Address Space Descriptor", NULL, ACPI_OSI_FEATURE, 0},
228 
229     /*
230      * All "optional" feature group strings (features that are implemented
231      * by the host) should be dynamically modified to VALID by the host via
232      * AcpiInstallInterface or AcpiUpdateInterfaces. Such optional feature
233      * group strings are set as INVALID by default here.
234      */
235 
236     {"Module Device",               NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
237     {"Processor Device",            NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
238     {"3.0 Thermal Model",           NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
239     {"3.0 _SCP Extensions",         NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
240     {"Processor Aggregator Device", NULL, ACPI_OSI_OPTIONAL_FEATURE, 0}
241 };
242 
243 
244 /*******************************************************************************
245  *
246  * FUNCTION:    AcpiUtInitializeInterfaces
247  *
248  * PARAMETERS:  None
249  *
250  * RETURN:      Status
251  *
252  * DESCRIPTION: Initialize the global _OSI supported interfaces list
253  *
254  ******************************************************************************/
255 
256 ACPI_STATUS
257 AcpiUtInitializeInterfaces (
258     void)
259 {
260     ACPI_STATUS             Status;
261     UINT32                  i;
262 
263 
264     Status = AcpiOsAcquireMutex (AcpiGbl_OsiMutex, ACPI_WAIT_FOREVER);
265     if (ACPI_FAILURE (Status))
266     {
267         return (Status);
268     }
269 
270     AcpiGbl_SupportedInterfaces = AcpiDefaultSupportedInterfaces;
271 
272     /* Link the static list of supported interfaces */
273 
274     for (i = 0;
275         i < (ACPI_ARRAY_LENGTH (AcpiDefaultSupportedInterfaces) - 1);
276         i++)
277     {
278         AcpiDefaultSupportedInterfaces[i].Next =
279             &AcpiDefaultSupportedInterfaces[(ACPI_SIZE) i + 1];
280     }
281 
282     AcpiOsReleaseMutex (AcpiGbl_OsiMutex);
283     return (AE_OK);
284 }
285 
286 
287 /*******************************************************************************
288  *
289  * FUNCTION:    AcpiUtInterfaceTerminate
290  *
291  * PARAMETERS:  None
292  *
293  * RETURN:      Status
294  *
295  * DESCRIPTION: Delete all interfaces in the global list. Sets
296  *              AcpiGbl_SupportedInterfaces to NULL.
297  *
298  ******************************************************************************/
299 
300 ACPI_STATUS
301 AcpiUtInterfaceTerminate (
302     void)
303 {
304     ACPI_STATUS             Status;
305     ACPI_INTERFACE_INFO     *NextInterface;
306 
307 
308     Status = AcpiOsAcquireMutex (AcpiGbl_OsiMutex, ACPI_WAIT_FOREVER);
309     if (ACPI_FAILURE (Status))
310     {
311         return (Status);
312     }
313 
314     NextInterface = AcpiGbl_SupportedInterfaces;
315     while (NextInterface)
316     {
317         AcpiGbl_SupportedInterfaces = NextInterface->Next;
318 
319         if (NextInterface->Flags & ACPI_OSI_DYNAMIC)
320         {
321             /* Only interfaces added at runtime can be freed */
322 
323             ACPI_FREE (NextInterface->Name);
324             ACPI_FREE (NextInterface);
325         }
326         else
327         {
328             /* Interface is in static list. Reset it to invalid or valid. */
329 
330             if (NextInterface->Flags & ACPI_OSI_DEFAULT_INVALID)
331             {
332                 NextInterface->Flags |= ACPI_OSI_INVALID;
333             }
334             else
335             {
336                 NextInterface->Flags &= ~ACPI_OSI_INVALID;
337             }
338         }
339 
340         NextInterface = AcpiGbl_SupportedInterfaces;
341     }
342 
343     AcpiOsReleaseMutex (AcpiGbl_OsiMutex);
344     return (AE_OK);
345 }
346 
347 
348 /*******************************************************************************
349  *
350  * FUNCTION:    AcpiUtInstallInterface
351  *
352  * PARAMETERS:  InterfaceName       - The interface to install
353  *
354  * RETURN:      Status
355  *
356  * DESCRIPTION: Install the interface into the global interface list.
357  *              Caller MUST hold AcpiGbl_OsiMutex
358  *
359  ******************************************************************************/
360 
361 ACPI_STATUS
362 AcpiUtInstallInterface (
363     ACPI_STRING             InterfaceName)
364 {
365     ACPI_INTERFACE_INFO     *InterfaceInfo;
366 
367 
368     /* Allocate info block and space for the name string */
369 
370     InterfaceInfo = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_INTERFACE_INFO));
371     if (!InterfaceInfo)
372     {
373         return (AE_NO_MEMORY);
374     }
375 
376     InterfaceInfo->Name = ACPI_ALLOCATE_ZEROED (strlen (InterfaceName) + 1);
377     if (!InterfaceInfo->Name)
378     {
379         ACPI_FREE (InterfaceInfo);
380         return (AE_NO_MEMORY);
381     }
382 
383     /* Initialize new info and insert at the head of the global list */
384 
385     strcpy (InterfaceInfo->Name, InterfaceName);
386     InterfaceInfo->Flags = ACPI_OSI_DYNAMIC;
387     InterfaceInfo->Next = AcpiGbl_SupportedInterfaces;
388 
389     AcpiGbl_SupportedInterfaces = InterfaceInfo;
390     return (AE_OK);
391 }
392 
393 
394 /*******************************************************************************
395  *
396  * FUNCTION:    AcpiUtRemoveInterface
397  *
398  * PARAMETERS:  InterfaceName       - The interface to remove
399  *
400  * RETURN:      Status
401  *
402  * DESCRIPTION: Remove the interface from the global interface list.
403  *              Caller MUST hold AcpiGbl_OsiMutex
404  *
405  ******************************************************************************/
406 
407 ACPI_STATUS
408 AcpiUtRemoveInterface (
409     ACPI_STRING             InterfaceName)
410 {
411     ACPI_INTERFACE_INFO     *PreviousInterface;
412     ACPI_INTERFACE_INFO     *NextInterface;
413 
414 
415     PreviousInterface = NextInterface = AcpiGbl_SupportedInterfaces;
416     while (NextInterface)
417     {
418         if (!strcmp (InterfaceName, NextInterface->Name))
419         {
420             /*
421              * Found: name is in either the static list
422              * or was added at runtime
423              */
424             if (NextInterface->Flags & ACPI_OSI_DYNAMIC)
425             {
426                 /* Interface was added dynamically, remove and free it */
427 
428                 if (PreviousInterface == NextInterface)
429                 {
430                     AcpiGbl_SupportedInterfaces = NextInterface->Next;
431                 }
432                 else
433                 {
434                     PreviousInterface->Next = NextInterface->Next;
435                 }
436 
437                 ACPI_FREE (NextInterface->Name);
438                 ACPI_FREE (NextInterface);
439             }
440             else
441             {
442                 /*
443                  * Interface is in static list. If marked invalid, then
444                  * it does not actually exist. Else, mark it invalid.
445                  */
446                 if (NextInterface->Flags & ACPI_OSI_INVALID)
447                 {
448                     return (AE_NOT_EXIST);
449                 }
450 
451                 NextInterface->Flags |= ACPI_OSI_INVALID;
452             }
453 
454             return (AE_OK);
455         }
456 
457         PreviousInterface = NextInterface;
458         NextInterface = NextInterface->Next;
459     }
460 
461     /* Interface was not found */
462 
463     return (AE_NOT_EXIST);
464 }
465 
466 
467 /*******************************************************************************
468  *
469  * FUNCTION:    AcpiUtUpdateInterfaces
470  *
471  * PARAMETERS:  Action              - Actions to be performed during the
472  *                                    update
473  *
474  * RETURN:      Status
475  *
476  * DESCRIPTION: Update _OSI interface strings, disabling or enabling OS vendor
477  *              strings or/and feature group strings.
478  *              Caller MUST hold AcpiGbl_OsiMutex
479  *
480  ******************************************************************************/
481 
482 ACPI_STATUS
483 AcpiUtUpdateInterfaces (
484     UINT8                   Action)
485 {
486     ACPI_INTERFACE_INFO     *NextInterface;
487 
488 
489     NextInterface = AcpiGbl_SupportedInterfaces;
490     while (NextInterface)
491     {
492         if (((NextInterface->Flags & ACPI_OSI_FEATURE) &&
493              (Action & ACPI_FEATURE_STRINGS)) ||
494             (!(NextInterface->Flags & ACPI_OSI_FEATURE) &&
495              (Action & ACPI_VENDOR_STRINGS)))
496         {
497             if (Action & ACPI_DISABLE_INTERFACES)
498             {
499                 /* Mark the interfaces as invalid */
500 
501                 NextInterface->Flags |= ACPI_OSI_INVALID;
502             }
503             else
504             {
505                 /* Mark the interfaces as valid */
506 
507                 NextInterface->Flags &= ~ACPI_OSI_INVALID;
508             }
509         }
510 
511         NextInterface = NextInterface->Next;
512     }
513 
514     return (AE_OK);
515 }
516 
517 
518 /*******************************************************************************
519  *
520  * FUNCTION:    AcpiUtGetInterface
521  *
522  * PARAMETERS:  InterfaceName       - The interface to find
523  *
524  * RETURN:      ACPI_INTERFACE_INFO if found. NULL if not found.
525  *
526  * DESCRIPTION: Search for the specified interface name in the global list.
527  *              Caller MUST hold AcpiGbl_OsiMutex
528  *
529  ******************************************************************************/
530 
531 ACPI_INTERFACE_INFO *
532 AcpiUtGetInterface (
533     ACPI_STRING             InterfaceName)
534 {
535     ACPI_INTERFACE_INFO     *NextInterface;
536 
537 
538     NextInterface = AcpiGbl_SupportedInterfaces;
539     while (NextInterface)
540     {
541         if (!strcmp (InterfaceName, NextInterface->Name))
542         {
543             return (NextInterface);
544         }
545 
546         NextInterface = NextInterface->Next;
547     }
548 
549     return (NULL);
550 }
551 
552 
553 /*******************************************************************************
554  *
555  * FUNCTION:    AcpiUtOsiImplementation
556  *
557  * PARAMETERS:  WalkState           - Current walk state
558  *
559  * RETURN:      Status
560  *              Integer: TRUE (0) if input string is matched
561  *                       FALSE (-1) if string is not matched
562  *
563  * DESCRIPTION: Implementation of the _OSI predefined control method. When
564  *              an invocation of _OSI is encountered in the system AML,
565  *              control is transferred to this function.
566  *
567  * (August 2016)
568  * Note:  _OSI is now defined to return "Ones" to indicate a match, for
569  * compatibility with other ACPI implementations. On a 32-bit DSDT, Ones
570  * is 0xFFFFFFFF. On a 64-bit DSDT, Ones is 0xFFFFFFFFFFFFFFFF
571  * (ACPI_UINT64_MAX).
572  *
573  * This function always returns ACPI_UINT64_MAX for TRUE, and later code
574  * will truncate this to 32 bits if necessary.
575  *
576  ******************************************************************************/
577 
578 ACPI_STATUS
579 AcpiUtOsiImplementation (
580     ACPI_WALK_STATE         *WalkState)
581 {
582     ACPI_OPERAND_OBJECT     *StringDesc;
583     ACPI_OPERAND_OBJECT     *ReturnDesc;
584     ACPI_INTERFACE_INFO     *InterfaceInfo;
585     ACPI_INTERFACE_HANDLER  InterfaceHandler;
586     ACPI_STATUS             Status;
587     UINT64                  ReturnValue;
588 
589 
590     ACPI_FUNCTION_TRACE (UtOsiImplementation);
591 
592 
593     /* Validate the string input argument (from the AML caller) */
594 
595     StringDesc = WalkState->Arguments[0].Object;
596     if (!StringDesc ||
597         (StringDesc->Common.Type != ACPI_TYPE_STRING))
598     {
599         return_ACPI_STATUS (AE_TYPE);
600     }
601 
602     /* Create a return object */
603 
604     ReturnDesc = AcpiUtCreateInternalObject (ACPI_TYPE_INTEGER);
605     if (!ReturnDesc)
606     {
607         return_ACPI_STATUS (AE_NO_MEMORY);
608     }
609 
610     /* Default return value is 0, NOT SUPPORTED */
611 
612     ReturnValue = 0;
613     Status = AcpiOsAcquireMutex (AcpiGbl_OsiMutex, ACPI_WAIT_FOREVER);
614     if (ACPI_FAILURE (Status))
615     {
616         AcpiUtRemoveReference (ReturnDesc);
617         return_ACPI_STATUS (Status);
618     }
619 
620     /* Lookup the interface in the global _OSI list */
621 
622     InterfaceInfo = AcpiUtGetInterface (StringDesc->String.Pointer);
623     if (InterfaceInfo &&
624         !(InterfaceInfo->Flags & ACPI_OSI_INVALID))
625     {
626         /*
627          * The interface is supported.
628          * Update the OsiData if necessary. We keep track of the latest
629          * version of Windows that has been requested by the BIOS.
630          */
631         if (InterfaceInfo->Value > AcpiGbl_OsiData)
632         {
633             AcpiGbl_OsiData = InterfaceInfo->Value;
634         }
635 
636         ReturnValue = ACPI_UINT64_MAX;
637     }
638 
639     AcpiOsReleaseMutex (AcpiGbl_OsiMutex);
640 
641     /*
642      * Invoke an optional _OSI interface handler. The host OS may wish
643      * to do some interface-specific handling. For example, warn about
644      * certain interfaces or override the true/false support value.
645      */
646     InterfaceHandler = AcpiGbl_InterfaceHandler;
647     if (InterfaceHandler)
648     {
649         if (InterfaceHandler (
650             StringDesc->String.Pointer, (UINT32) ReturnValue))
651         {
652             ReturnValue = ACPI_UINT64_MAX;
653         }
654     }
655 
656     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INFO,
657         "ACPI: BIOS _OSI(\"%s\") is %ssupported\n",
658         StringDesc->String.Pointer, ReturnValue == 0 ? "not " : ""));
659 
660     /* Complete the return object */
661 
662     ReturnDesc->Integer.Value = ReturnValue;
663     WalkState->ReturnDesc = ReturnDesc;
664     return_ACPI_STATUS (AE_OK);
665 }
666