xref: /freebsd/sys/contrib/dev/acpica/components/utilities/utosi.c (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
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 - 2023, 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     {"Windows 2021",        NULL, 0, ACPI_OSI_WIN_11},           /* Windows 11 - Added 01/2022 */
225 
226     /* Feature Group Strings */
227 
228     {"Extended Address Space Descriptor", NULL, ACPI_OSI_FEATURE, 0},
229 
230     /*
231      * All "optional" feature group strings (features that are implemented
232      * by the host) should be dynamically modified to VALID by the host via
233      * AcpiInstallInterface or AcpiUpdateInterfaces. Such optional feature
234      * group strings are set as INVALID by default here.
235      */
236 
237     {"Module Device",               NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
238     {"Processor Device",            NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
239     {"3.0 Thermal Model",           NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
240     {"3.0 _SCP Extensions",         NULL, ACPI_OSI_OPTIONAL_FEATURE, 0},
241     {"Processor Aggregator Device", NULL, ACPI_OSI_OPTIONAL_FEATURE, 0}
242 };
243 
244 
245 /*******************************************************************************
246  *
247  * FUNCTION:    AcpiUtInitializeInterfaces
248  *
249  * PARAMETERS:  None
250  *
251  * RETURN:      Status
252  *
253  * DESCRIPTION: Initialize the global _OSI supported interfaces list
254  *
255  ******************************************************************************/
256 
257 ACPI_STATUS
258 AcpiUtInitializeInterfaces (
259     void)
260 {
261     ACPI_STATUS             Status;
262     UINT32                  i;
263 
264 
265     Status = AcpiOsAcquireMutex (AcpiGbl_OsiMutex, ACPI_WAIT_FOREVER);
266     if (ACPI_FAILURE (Status))
267     {
268         return (Status);
269     }
270 
271     AcpiGbl_SupportedInterfaces = AcpiDefaultSupportedInterfaces;
272 
273     /* Link the static list of supported interfaces */
274 
275     for (i = 0;
276         i < (ACPI_ARRAY_LENGTH (AcpiDefaultSupportedInterfaces) - 1);
277         i++)
278     {
279         AcpiDefaultSupportedInterfaces[i].Next =
280             &AcpiDefaultSupportedInterfaces[(ACPI_SIZE) i + 1];
281     }
282 
283     AcpiOsReleaseMutex (AcpiGbl_OsiMutex);
284     return (AE_OK);
285 }
286 
287 
288 /*******************************************************************************
289  *
290  * FUNCTION:    AcpiUtInterfaceTerminate
291  *
292  * PARAMETERS:  None
293  *
294  * RETURN:      Status
295  *
296  * DESCRIPTION: Delete all interfaces in the global list. Sets
297  *              AcpiGbl_SupportedInterfaces to NULL.
298  *
299  ******************************************************************************/
300 
301 ACPI_STATUS
302 AcpiUtInterfaceTerminate (
303     void)
304 {
305     ACPI_STATUS             Status;
306     ACPI_INTERFACE_INFO     *NextInterface;
307 
308 
309     Status = AcpiOsAcquireMutex (AcpiGbl_OsiMutex, ACPI_WAIT_FOREVER);
310     if (ACPI_FAILURE (Status))
311     {
312         return (Status);
313     }
314 
315     NextInterface = AcpiGbl_SupportedInterfaces;
316     while (NextInterface)
317     {
318         AcpiGbl_SupportedInterfaces = NextInterface->Next;
319 
320         if (NextInterface->Flags & ACPI_OSI_DYNAMIC)
321         {
322             /* Only interfaces added at runtime can be freed */
323 
324             ACPI_FREE (NextInterface->Name);
325             ACPI_FREE (NextInterface);
326         }
327         else
328         {
329             /* Interface is in static list. Reset it to invalid or valid. */
330 
331             if (NextInterface->Flags & ACPI_OSI_DEFAULT_INVALID)
332             {
333                 NextInterface->Flags |= ACPI_OSI_INVALID;
334             }
335             else
336             {
337                 NextInterface->Flags &= ~ACPI_OSI_INVALID;
338             }
339         }
340 
341         NextInterface = AcpiGbl_SupportedInterfaces;
342     }
343 
344     AcpiOsReleaseMutex (AcpiGbl_OsiMutex);
345     return (AE_OK);
346 }
347 
348 
349 /*******************************************************************************
350  *
351  * FUNCTION:    AcpiUtInstallInterface
352  *
353  * PARAMETERS:  InterfaceName       - The interface to install
354  *
355  * RETURN:      Status
356  *
357  * DESCRIPTION: Install the interface into the global interface list.
358  *              Caller MUST hold AcpiGbl_OsiMutex
359  *
360  ******************************************************************************/
361 
362 ACPI_STATUS
363 AcpiUtInstallInterface (
364     ACPI_STRING             InterfaceName)
365 {
366     ACPI_INTERFACE_INFO     *InterfaceInfo;
367 
368 
369     /* Allocate info block and space for the name string */
370 
371     InterfaceInfo = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_INTERFACE_INFO));
372     if (!InterfaceInfo)
373     {
374         return (AE_NO_MEMORY);
375     }
376 
377     InterfaceInfo->Name = ACPI_ALLOCATE_ZEROED (strlen (InterfaceName) + 1);
378     if (!InterfaceInfo->Name)
379     {
380         ACPI_FREE (InterfaceInfo);
381         return (AE_NO_MEMORY);
382     }
383 
384     /* Initialize new info and insert at the head of the global list */
385 
386     strcpy (InterfaceInfo->Name, InterfaceName);
387     InterfaceInfo->Flags = ACPI_OSI_DYNAMIC;
388     InterfaceInfo->Next = AcpiGbl_SupportedInterfaces;
389 
390     AcpiGbl_SupportedInterfaces = InterfaceInfo;
391     return (AE_OK);
392 }
393 
394 
395 /*******************************************************************************
396  *
397  * FUNCTION:    AcpiUtRemoveInterface
398  *
399  * PARAMETERS:  InterfaceName       - The interface to remove
400  *
401  * RETURN:      Status
402  *
403  * DESCRIPTION: Remove the interface from the global interface list.
404  *              Caller MUST hold AcpiGbl_OsiMutex
405  *
406  ******************************************************************************/
407 
408 ACPI_STATUS
409 AcpiUtRemoveInterface (
410     ACPI_STRING             InterfaceName)
411 {
412     ACPI_INTERFACE_INFO     *PreviousInterface;
413     ACPI_INTERFACE_INFO     *NextInterface;
414 
415 
416     PreviousInterface = NextInterface = AcpiGbl_SupportedInterfaces;
417     while (NextInterface)
418     {
419         if (!strcmp (InterfaceName, NextInterface->Name))
420         {
421             /*
422              * Found: name is in either the static list
423              * or was added at runtime
424              */
425             if (NextInterface->Flags & ACPI_OSI_DYNAMIC)
426             {
427                 /* Interface was added dynamically, remove and free it */
428 
429                 if (PreviousInterface == NextInterface)
430                 {
431                     AcpiGbl_SupportedInterfaces = NextInterface->Next;
432                 }
433                 else
434                 {
435                     PreviousInterface->Next = NextInterface->Next;
436                 }
437 
438                 ACPI_FREE (NextInterface->Name);
439                 ACPI_FREE (NextInterface);
440             }
441             else
442             {
443                 /*
444                  * Interface is in static list. If marked invalid, then
445                  * it does not actually exist. Else, mark it invalid.
446                  */
447                 if (NextInterface->Flags & ACPI_OSI_INVALID)
448                 {
449                     return (AE_NOT_EXIST);
450                 }
451 
452                 NextInterface->Flags |= ACPI_OSI_INVALID;
453             }
454 
455             return (AE_OK);
456         }
457 
458         PreviousInterface = NextInterface;
459         NextInterface = NextInterface->Next;
460     }
461 
462     /* Interface was not found */
463 
464     return (AE_NOT_EXIST);
465 }
466 
467 
468 /*******************************************************************************
469  *
470  * FUNCTION:    AcpiUtUpdateInterfaces
471  *
472  * PARAMETERS:  Action              - Actions to be performed during the
473  *                                    update
474  *
475  * RETURN:      Status
476  *
477  * DESCRIPTION: Update _OSI interface strings, disabling or enabling OS vendor
478  *              strings or/and feature group strings.
479  *              Caller MUST hold AcpiGbl_OsiMutex
480  *
481  ******************************************************************************/
482 
483 ACPI_STATUS
484 AcpiUtUpdateInterfaces (
485     UINT8                   Action)
486 {
487     ACPI_INTERFACE_INFO     *NextInterface;
488 
489 
490     NextInterface = AcpiGbl_SupportedInterfaces;
491     while (NextInterface)
492     {
493         if (((NextInterface->Flags & ACPI_OSI_FEATURE) &&
494              (Action & ACPI_FEATURE_STRINGS)) ||
495             (!(NextInterface->Flags & ACPI_OSI_FEATURE) &&
496              (Action & ACPI_VENDOR_STRINGS)))
497         {
498             if (Action & ACPI_DISABLE_INTERFACES)
499             {
500                 /* Mark the interfaces as invalid */
501 
502                 NextInterface->Flags |= ACPI_OSI_INVALID;
503             }
504             else
505             {
506                 /* Mark the interfaces as valid */
507 
508                 NextInterface->Flags &= ~ACPI_OSI_INVALID;
509             }
510         }
511 
512         NextInterface = NextInterface->Next;
513     }
514 
515     return (AE_OK);
516 }
517 
518 
519 /*******************************************************************************
520  *
521  * FUNCTION:    AcpiUtGetInterface
522  *
523  * PARAMETERS:  InterfaceName       - The interface to find
524  *
525  * RETURN:      ACPI_INTERFACE_INFO if found. NULL if not found.
526  *
527  * DESCRIPTION: Search for the specified interface name in the global list.
528  *              Caller MUST hold AcpiGbl_OsiMutex
529  *
530  ******************************************************************************/
531 
532 ACPI_INTERFACE_INFO *
533 AcpiUtGetInterface (
534     ACPI_STRING             InterfaceName)
535 {
536     ACPI_INTERFACE_INFO     *NextInterface;
537 
538 
539     NextInterface = AcpiGbl_SupportedInterfaces;
540     while (NextInterface)
541     {
542         if (!strcmp (InterfaceName, NextInterface->Name))
543         {
544             return (NextInterface);
545         }
546 
547         NextInterface = NextInterface->Next;
548     }
549 
550     return (NULL);
551 }
552 
553 
554 /*******************************************************************************
555  *
556  * FUNCTION:    AcpiUtOsiImplementation
557  *
558  * PARAMETERS:  WalkState           - Current walk state
559  *
560  * RETURN:      Status
561  *              Integer: TRUE (0) if input string is matched
562  *                       FALSE (-1) if string is not matched
563  *
564  * DESCRIPTION: Implementation of the _OSI predefined control method. When
565  *              an invocation of _OSI is encountered in the system AML,
566  *              control is transferred to this function.
567  *
568  * (August 2016)
569  * Note:  _OSI is now defined to return "Ones" to indicate a match, for
570  * compatibility with other ACPI implementations. On a 32-bit DSDT, Ones
571  * is 0xFFFFFFFF. On a 64-bit DSDT, Ones is 0xFFFFFFFFFFFFFFFF
572  * (ACPI_UINT64_MAX).
573  *
574  * This function always returns ACPI_UINT64_MAX for TRUE, and later code
575  * will truncate this to 32 bits if necessary.
576  *
577  ******************************************************************************/
578 
579 ACPI_STATUS
580 AcpiUtOsiImplementation (
581     ACPI_WALK_STATE         *WalkState)
582 {
583     ACPI_OPERAND_OBJECT     *StringDesc;
584     ACPI_OPERAND_OBJECT     *ReturnDesc;
585     ACPI_INTERFACE_INFO     *InterfaceInfo;
586     ACPI_INTERFACE_HANDLER  InterfaceHandler;
587     ACPI_STATUS             Status;
588     UINT64                  ReturnValue;
589 
590 
591     ACPI_FUNCTION_TRACE (UtOsiImplementation);
592 
593 
594     /* Validate the string input argument (from the AML caller) */
595 
596     StringDesc = WalkState->Arguments[0].Object;
597     if (!StringDesc ||
598         (StringDesc->Common.Type != ACPI_TYPE_STRING))
599     {
600         return_ACPI_STATUS (AE_TYPE);
601     }
602 
603     /* Create a return object */
604 
605     ReturnDesc = AcpiUtCreateInternalObject (ACPI_TYPE_INTEGER);
606     if (!ReturnDesc)
607     {
608         return_ACPI_STATUS (AE_NO_MEMORY);
609     }
610 
611     /* Default return value is 0, NOT SUPPORTED */
612 
613     ReturnValue = 0;
614     Status = AcpiOsAcquireMutex (AcpiGbl_OsiMutex, ACPI_WAIT_FOREVER);
615     if (ACPI_FAILURE (Status))
616     {
617         AcpiUtRemoveReference (ReturnDesc);
618         return_ACPI_STATUS (Status);
619     }
620 
621     /* Lookup the interface in the global _OSI list */
622 
623     InterfaceInfo = AcpiUtGetInterface (StringDesc->String.Pointer);
624     if (InterfaceInfo &&
625         !(InterfaceInfo->Flags & ACPI_OSI_INVALID))
626     {
627         /*
628          * The interface is supported.
629          * Update the OsiData if necessary. We keep track of the latest
630          * version of Windows that has been requested by the BIOS.
631          */
632         if (InterfaceInfo->Value > AcpiGbl_OsiData)
633         {
634             AcpiGbl_OsiData = InterfaceInfo->Value;
635         }
636 
637         ReturnValue = ACPI_UINT64_MAX;
638     }
639 
640     AcpiOsReleaseMutex (AcpiGbl_OsiMutex);
641 
642     /*
643      * Invoke an optional _OSI interface handler. The host OS may wish
644      * to do some interface-specific handling. For example, warn about
645      * certain interfaces or override the true/false support value.
646      */
647     InterfaceHandler = AcpiGbl_InterfaceHandler;
648     if (InterfaceHandler)
649     {
650         if (InterfaceHandler (
651             StringDesc->String.Pointer, (UINT32) ReturnValue))
652         {
653             ReturnValue = ACPI_UINT64_MAX;
654         }
655     }
656 
657     ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INFO,
658         "ACPI: BIOS _OSI(\"%s\") is %ssupported\n",
659         StringDesc->String.Pointer, ReturnValue == 0 ? "not " : ""));
660 
661     /* Complete the return object */
662 
663     ReturnDesc->Integer.Value = ReturnValue;
664     WalkState->ReturnDesc = ReturnDesc;
665     return_ACPI_STATUS (AE_OK);
666 }
667