xref: /haiku/src/add-ons/kernel/bus_managers/acpi/acpica/components/namespace/nsxfname.c (revision 04a0e9c7b68cbe3a43d38e2bca8e860fd80936fb)
1 /******************************************************************************
2  *
3  * Module Name: nsxfname - Public interfaces to the ACPI subsystem
4  *                         ACPI Namespace oriented interfaces
5  *
6  *****************************************************************************/
7 
8 /******************************************************************************
9  *
10  * 1. Copyright Notice
11  *
12  * Some or all of this work - Copyright (c) 1999 - 2013, Intel Corp.
13  * All rights reserved.
14  *
15  * 2. License
16  *
17  * 2.1. This is your license from Intel Corp. under its intellectual property
18  * rights. You may have additional license terms from the party that provided
19  * you this software, covering your right to use that party's intellectual
20  * property rights.
21  *
22  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
23  * copy of the source code appearing in this file ("Covered Code") an
24  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
25  * base code distributed originally by Intel ("Original Intel Code") to copy,
26  * make derivatives, distribute, use and display any portion of the Covered
27  * Code in any form, with the right to sublicense such rights; and
28  *
29  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
30  * license (with the right to sublicense), under only those claims of Intel
31  * patents that are infringed by the Original Intel Code, to make, use, sell,
32  * offer to sell, and import the Covered Code and derivative works thereof
33  * solely to the minimum extent necessary to exercise the above copyright
34  * license, and in no event shall the patent license extend to any additions
35  * to or modifications of the Original Intel Code. No other license or right
36  * is granted directly or by implication, estoppel or otherwise;
37  *
38  * The above copyright and patent license is granted only if the following
39  * conditions are met:
40  *
41  * 3. Conditions
42  *
43  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
44  * Redistribution of source code of any substantial portion of the Covered
45  * Code or modification with rights to further distribute source must include
46  * the above Copyright Notice, the above License, this list of Conditions,
47  * and the following Disclaimer and Export Compliance provision. In addition,
48  * Licensee must cause all Covered Code to which Licensee contributes to
49  * contain a file documenting the changes Licensee made to create that Covered
50  * Code and the date of any change. Licensee must include in that file the
51  * documentation of any changes made by any predecessor Licensee. Licensee
52  * must include a prominent statement that the modification is derived,
53  * directly or indirectly, from Original Intel Code.
54  *
55  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
56  * Redistribution of source code of any substantial portion of the Covered
57  * Code or modification without rights to further distribute source must
58  * include the following Disclaimer and Export Compliance provision in the
59  * documentation and/or other materials provided with distribution. In
60  * addition, Licensee may not authorize further sublicense of source of any
61  * portion of the Covered Code, and must include terms to the effect that the
62  * license from Licensee to its licensee is limited to the intellectual
63  * property embodied in the software Licensee provides to its licensee, and
64  * not to intellectual property embodied in modifications its licensee may
65  * make.
66  *
67  * 3.3. Redistribution of Executable. Redistribution in executable form of any
68  * substantial portion of the Covered Code or modification must reproduce the
69  * above Copyright Notice, and the following Disclaimer and Export Compliance
70  * provision in the documentation and/or other materials provided with the
71  * distribution.
72  *
73  * 3.4. Intel retains all right, title, and interest in and to the Original
74  * Intel Code.
75  *
76  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
77  * Intel shall be used in advertising or otherwise to promote the sale, use or
78  * other dealings in products derived from or relating to the Covered Code
79  * without prior written authorization from Intel.
80  *
81  * 4. Disclaimer and Export Compliance
82  *
83  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
84  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
85  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
86  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
87  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
88  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
89  * PARTICULAR PURPOSE.
90  *
91  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
92  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
93  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
94  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
95  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
96  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
97  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
98  * LIMITED REMEDY.
99  *
100  * 4.3. Licensee shall not export, either directly or indirectly, any of this
101  * software or system incorporating such software without first obtaining any
102  * required license or other approval from the U. S. Department of Commerce or
103  * any other agency or department of the United States Government. In the
104  * event Licensee exports any such software from the United States or
105  * re-exports any such software from a foreign destination, Licensee shall
106  * ensure that the distribution and export/re-export of the software is in
107  * compliance with all laws, regulations, orders, or other restrictions of the
108  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
109  * any of its subsidiaries will export/re-export any technical data, process,
110  * software, or service, directly or indirectly, to any country for which the
111  * United States government or any agency thereof requires an export license,
112  * other governmental approval, or letter of assurance, without first obtaining
113  * such license, approval or letter.
114  *
115  *****************************************************************************/
116 
117 #define __NSXFNAME_C__
118 
119 #include "acpi.h"
120 #include "accommon.h"
121 #include "acnamesp.h"
122 #include "acparser.h"
123 #include "amlcode.h"
124 
125 
126 #define _COMPONENT          ACPI_NAMESPACE
127         ACPI_MODULE_NAME    ("nsxfname")
128 
129 /* Local prototypes */
130 
131 static char *
132 AcpiNsCopyDeviceId (
133     ACPI_PNP_DEVICE_ID      *Dest,
134     ACPI_PNP_DEVICE_ID      *Source,
135     char                    *StringArea);
136 
137 
138 /******************************************************************************
139  *
140  * FUNCTION:    AcpiGetHandle
141  *
142  * PARAMETERS:  Parent          - Object to search under (search scope).
143  *              Pathname        - Pointer to an asciiz string containing the
144  *                                name
145  *              RetHandle       - Where the return handle is returned
146  *
147  * RETURN:      Status
148  *
149  * DESCRIPTION: This routine will search for a caller specified name in the
150  *              name space. The caller can restrict the search region by
151  *              specifying a non NULL parent. The parent value is itself a
152  *              namespace handle.
153  *
154  ******************************************************************************/
155 
156 ACPI_STATUS
157 AcpiGetHandle (
158     ACPI_HANDLE             Parent,
159     ACPI_STRING             Pathname,
160     ACPI_HANDLE             *RetHandle)
161 {
162     ACPI_STATUS             Status;
163     ACPI_NAMESPACE_NODE     *Node = NULL;
164     ACPI_NAMESPACE_NODE     *PrefixNode = NULL;
165 
166 
167     ACPI_FUNCTION_ENTRY ();
168 
169 
170     /* Parameter Validation */
171 
172     if (!RetHandle || !Pathname)
173     {
174         return (AE_BAD_PARAMETER);
175     }
176 
177     /* Convert a parent handle to a prefix node */
178 
179     if (Parent)
180     {
181         PrefixNode = AcpiNsValidateHandle (Parent);
182         if (!PrefixNode)
183         {
184             return (AE_BAD_PARAMETER);
185         }
186     }
187 
188     /*
189      * Valid cases are:
190      * 1) Fully qualified pathname
191      * 2) Parent + Relative pathname
192      *
193      * Error for <null Parent + relative path>
194      */
195     if (ACPI_IS_ROOT_PREFIX (Pathname[0]))
196     {
197         /* Pathname is fully qualified (starts with '\') */
198 
199         /* Special case for root-only, since we can't search for it */
200 
201         if (!ACPI_STRCMP (Pathname, ACPI_NS_ROOT_PATH))
202         {
203             *RetHandle = ACPI_CAST_PTR (ACPI_HANDLE, AcpiGbl_RootNode);
204             return (AE_OK);
205         }
206     }
207     else if (!PrefixNode)
208     {
209         /* Relative path with null prefix is disallowed */
210 
211         return (AE_BAD_PARAMETER);
212     }
213 
214     /* Find the Node and convert to a handle */
215 
216     Status = AcpiNsGetNode (PrefixNode, Pathname, ACPI_NS_NO_UPSEARCH, &Node);
217     if (ACPI_SUCCESS (Status))
218     {
219         *RetHandle = ACPI_CAST_PTR (ACPI_HANDLE, Node);
220     }
221 
222     return (Status);
223 }
224 
225 ACPI_EXPORT_SYMBOL (AcpiGetHandle)
226 
227 
228 /******************************************************************************
229  *
230  * FUNCTION:    AcpiGetName
231  *
232  * PARAMETERS:  Handle          - Handle to be converted to a pathname
233  *              NameType        - Full pathname or single segment
234  *              Buffer          - Buffer for returned path
235  *
236  * RETURN:      Pointer to a string containing the fully qualified Name.
237  *
238  * DESCRIPTION: This routine returns the fully qualified name associated with
239  *              the Handle parameter. This and the AcpiPathnameToHandle are
240  *              complementary functions.
241  *
242  ******************************************************************************/
243 
244 ACPI_STATUS
245 AcpiGetName (
246     ACPI_HANDLE             Handle,
247     UINT32                  NameType,
248     ACPI_BUFFER             *Buffer)
249 {
250     ACPI_STATUS             Status;
251     ACPI_NAMESPACE_NODE     *Node;
252     char                    *NodeName;
253 
254 
255     /* Parameter validation */
256 
257     if (NameType > ACPI_NAME_TYPE_MAX)
258     {
259         return (AE_BAD_PARAMETER);
260     }
261 
262     Status = AcpiUtValidateBuffer (Buffer);
263     if (ACPI_FAILURE (Status))
264     {
265         return (Status);
266     }
267 
268     if (NameType == ACPI_FULL_PATHNAME)
269     {
270         /* Get the full pathname (From the namespace root) */
271 
272         Status = AcpiNsHandleToPathname (Handle, Buffer);
273         return (Status);
274     }
275 
276     /*
277      * Wants the single segment ACPI name.
278      * Validate handle and convert to a namespace Node
279      */
280     Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
281     if (ACPI_FAILURE (Status))
282     {
283         return (Status);
284     }
285 
286     Node = AcpiNsValidateHandle (Handle);
287     if (!Node)
288     {
289         Status = AE_BAD_PARAMETER;
290         goto UnlockAndExit;
291     }
292 
293     /* Validate/Allocate/Clear caller buffer */
294 
295     Status = AcpiUtInitializeBuffer (Buffer, ACPI_PATH_SEGMENT_LENGTH);
296     if (ACPI_FAILURE (Status))
297     {
298         goto UnlockAndExit;
299     }
300 
301     /* Just copy the ACPI name from the Node and zero terminate it */
302 
303     NodeName = AcpiUtGetNodeName (Node);
304     ACPI_MOVE_NAME (Buffer->Pointer, NodeName);
305     ((char *) Buffer->Pointer) [ACPI_NAME_SIZE] = 0;
306     Status = AE_OK;
307 
308 
309 UnlockAndExit:
310 
311     (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
312     return (Status);
313 }
314 
315 ACPI_EXPORT_SYMBOL (AcpiGetName)
316 
317 
318 /******************************************************************************
319  *
320  * FUNCTION:    AcpiNsCopyDeviceId
321  *
322  * PARAMETERS:  Dest                - Pointer to the destination PNP_DEVICE_ID
323  *              Source              - Pointer to the source PNP_DEVICE_ID
324  *              StringArea          - Pointer to where to copy the dest string
325  *
326  * RETURN:      Pointer to the next string area
327  *
328  * DESCRIPTION: Copy a single PNP_DEVICE_ID, including the string data.
329  *
330  ******************************************************************************/
331 
332 static char *
333 AcpiNsCopyDeviceId (
334     ACPI_PNP_DEVICE_ID      *Dest,
335     ACPI_PNP_DEVICE_ID      *Source,
336     char                    *StringArea)
337 {
338 
339     /* Create the destination PNP_DEVICE_ID */
340 
341     Dest->String = StringArea;
342     Dest->Length = Source->Length;
343 
344     /* Copy actual string and return a pointer to the next string area */
345 
346     ACPI_MEMCPY (StringArea, Source->String, Source->Length);
347     return (StringArea + Source->Length);
348 }
349 
350 
351 /******************************************************************************
352  *
353  * FUNCTION:    AcpiGetObjectInfo
354  *
355  * PARAMETERS:  Handle              - Object Handle
356  *              ReturnBuffer        - Where the info is returned
357  *
358  * RETURN:      Status
359  *
360  * DESCRIPTION: Returns information about an object as gleaned from the
361  *              namespace node and possibly by running several standard
362  *              control methods (Such as in the case of a device.)
363  *
364  * For Device and Processor objects, run the Device _HID, _UID, _CID, _SUB,
365  * _STA, _ADR, _SxW, and _SxD methods.
366  *
367  * Note: Allocates the return buffer, must be freed by the caller.
368  *
369  ******************************************************************************/
370 
371 ACPI_STATUS
372 AcpiGetObjectInfo (
373     ACPI_HANDLE             Handle,
374     ACPI_DEVICE_INFO        **ReturnBuffer)
375 {
376     ACPI_NAMESPACE_NODE     *Node;
377     ACPI_DEVICE_INFO        *Info;
378     ACPI_PNP_DEVICE_ID_LIST *CidList = NULL;
379     ACPI_PNP_DEVICE_ID      *Hid = NULL;
380     ACPI_PNP_DEVICE_ID      *Uid = NULL;
381     ACPI_PNP_DEVICE_ID      *Sub = NULL;
382     char                    *NextIdString;
383     ACPI_OBJECT_TYPE        Type;
384     ACPI_NAME               Name;
385     UINT8                   ParamCount= 0;
386     UINT8                   Valid = 0;
387     UINT32                  InfoSize;
388     UINT32                  i;
389     ACPI_STATUS             Status;
390 
391 
392     /* Parameter validation */
393 
394     if (!Handle || !ReturnBuffer)
395     {
396         return (AE_BAD_PARAMETER);
397     }
398 
399     Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
400     if (ACPI_FAILURE (Status))
401     {
402         return (Status);
403     }
404 
405     Node = AcpiNsValidateHandle (Handle);
406     if (!Node)
407     {
408         (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
409         return (AE_BAD_PARAMETER);
410     }
411 
412     /* Get the namespace node data while the namespace is locked */
413 
414     InfoSize = sizeof (ACPI_DEVICE_INFO);
415     Type = Node->Type;
416     Name = Node->Name.Integer;
417 
418     if (Node->Type == ACPI_TYPE_METHOD)
419     {
420         ParamCount = Node->Object->Method.ParamCount;
421     }
422 
423     Status = AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
424     if (ACPI_FAILURE (Status))
425     {
426         return (Status);
427     }
428 
429     if ((Type == ACPI_TYPE_DEVICE) ||
430         (Type == ACPI_TYPE_PROCESSOR))
431     {
432         /*
433          * Get extra info for ACPI Device/Processor objects only:
434          * Run the Device _HID, _UID, _SUB, and _CID methods.
435          *
436          * Note: none of these methods are required, so they may or may
437          * not be present for this device. The Info->Valid bitfield is used
438          * to indicate which methods were found and run successfully.
439          */
440 
441         /* Execute the Device._HID method */
442 
443         Status = AcpiUtExecute_HID (Node, &Hid);
444         if (ACPI_SUCCESS (Status))
445         {
446             InfoSize += Hid->Length;
447             Valid |= ACPI_VALID_HID;
448         }
449 
450         /* Execute the Device._UID method */
451 
452         Status = AcpiUtExecute_UID (Node, &Uid);
453         if (ACPI_SUCCESS (Status))
454         {
455             InfoSize += Uid->Length;
456             Valid |= ACPI_VALID_UID;
457         }
458 
459         /* Execute the Device._SUB method */
460 
461         Status = AcpiUtExecute_SUB (Node, &Sub);
462         if (ACPI_SUCCESS (Status))
463         {
464             InfoSize += Sub->Length;
465             Valid |= ACPI_VALID_SUB;
466         }
467 
468         /* Execute the Device._CID method */
469 
470         Status = AcpiUtExecute_CID (Node, &CidList);
471         if (ACPI_SUCCESS (Status))
472         {
473             /* Add size of CID strings and CID pointer array */
474 
475             InfoSize += (CidList->ListSize - sizeof (ACPI_PNP_DEVICE_ID_LIST));
476             Valid |= ACPI_VALID_CID;
477         }
478     }
479 
480     /*
481      * Now that we have the variable-length data, we can allocate the
482      * return buffer
483      */
484     Info = ACPI_ALLOCATE_ZEROED (InfoSize);
485     if (!Info)
486     {
487         Status = AE_NO_MEMORY;
488         goto Cleanup;
489     }
490 
491     /* Get the fixed-length data */
492 
493     if ((Type == ACPI_TYPE_DEVICE) ||
494         (Type == ACPI_TYPE_PROCESSOR))
495     {
496         /*
497          * Get extra info for ACPI Device/Processor objects only:
498          * Run the _STA, _ADR and, SxW, and _SxD methods.
499          *
500          * Notes: none of these methods are required, so they may or may
501          * not be present for this device. The Info->Valid bitfield is used
502          * to indicate which methods were found and run successfully.
503          *
504          * For _STA, if the method does not exist, then (as per the ACPI
505          * specification), the returned CurrentStatus flags will indicate
506          * that the device is present/functional/enabled. Otherwise, the
507          * CurrentStatus flags reflect the value returned from _STA.
508          */
509 
510         /* Execute the Device._STA method */
511 
512         Status = AcpiUtExecute_STA (Node, &Info->CurrentStatus);
513         if (ACPI_SUCCESS (Status))
514         {
515             Valid |= ACPI_VALID_STA;
516         }
517 
518         /* Execute the Device._ADR method */
519 
520         Status = AcpiUtEvaluateNumericObject (METHOD_NAME__ADR, Node,
521                     &Info->Address);
522         if (ACPI_SUCCESS (Status))
523         {
524             Valid |= ACPI_VALID_ADR;
525         }
526 
527         /* Execute the Device._SxW methods */
528 
529         Status = AcpiUtExecutePowerMethods (Node,
530                     AcpiGbl_LowestDstateNames, ACPI_NUM_SxW_METHODS,
531                     Info->LowestDstates);
532         if (ACPI_SUCCESS (Status))
533         {
534             Valid |= ACPI_VALID_SXWS;
535         }
536 
537         /* Execute the Device._SxD methods */
538 
539         Status = AcpiUtExecutePowerMethods (Node,
540                     AcpiGbl_HighestDstateNames, ACPI_NUM_SxD_METHODS,
541                     Info->HighestDstates);
542         if (ACPI_SUCCESS (Status))
543         {
544             Valid |= ACPI_VALID_SXDS;
545         }
546     }
547 
548     /*
549      * Create a pointer to the string area of the return buffer.
550      * Point to the end of the base ACPI_DEVICE_INFO structure.
551      */
552     NextIdString = ACPI_CAST_PTR (char, Info->CompatibleIdList.Ids);
553     if (CidList)
554     {
555         /* Point past the CID PNP_DEVICE_ID array */
556 
557         NextIdString += ((ACPI_SIZE) CidList->Count * sizeof (ACPI_PNP_DEVICE_ID));
558     }
559 
560     /*
561      * Copy the HID, UID, SUB, and CIDs to the return buffer.
562      * The variable-length strings are copied to the reserved area
563      * at the end of the buffer.
564      *
565      * For HID and CID, check if the ID is a PCI Root Bridge.
566      */
567     if (Hid)
568     {
569         NextIdString = AcpiNsCopyDeviceId (&Info->HardwareId,
570             Hid, NextIdString);
571 
572         if (AcpiUtIsPciRootBridge (Hid->String))
573         {
574             Info->Flags |= ACPI_PCI_ROOT_BRIDGE;
575         }
576     }
577 
578     if (Uid)
579     {
580         NextIdString = AcpiNsCopyDeviceId (&Info->UniqueId,
581             Uid, NextIdString);
582     }
583 
584     if (Sub)
585     {
586         NextIdString = AcpiNsCopyDeviceId (&Info->SubsystemId,
587             Sub, NextIdString);
588     }
589 
590     if (CidList)
591     {
592         Info->CompatibleIdList.Count = CidList->Count;
593         Info->CompatibleIdList.ListSize = CidList->ListSize;
594 
595         /* Copy each CID */
596 
597         for (i = 0; i < CidList->Count; i++)
598         {
599             NextIdString = AcpiNsCopyDeviceId (&Info->CompatibleIdList.Ids[i],
600                 &CidList->Ids[i], NextIdString);
601 
602             if (AcpiUtIsPciRootBridge (CidList->Ids[i].String))
603             {
604                 Info->Flags |= ACPI_PCI_ROOT_BRIDGE;
605             }
606         }
607     }
608 
609     /* Copy the fixed-length data */
610 
611     Info->InfoSize = InfoSize;
612     Info->Type = Type;
613     Info->Name = Name;
614     Info->ParamCount = ParamCount;
615     Info->Valid = Valid;
616 
617     *ReturnBuffer = Info;
618     Status = AE_OK;
619 
620 
621 Cleanup:
622     if (Hid)
623     {
624         ACPI_FREE (Hid);
625     }
626     if (Uid)
627     {
628         ACPI_FREE (Uid);
629     }
630     if (Sub)
631     {
632         ACPI_FREE (Sub);
633     }
634     if (CidList)
635     {
636         ACPI_FREE (CidList);
637     }
638     return (Status);
639 }
640 
641 ACPI_EXPORT_SYMBOL (AcpiGetObjectInfo)
642 
643 
644 /******************************************************************************
645  *
646  * FUNCTION:    AcpiInstallMethod
647  *
648  * PARAMETERS:  Buffer         - An ACPI table containing one control method
649  *
650  * RETURN:      Status
651  *
652  * DESCRIPTION: Install a control method into the namespace. If the method
653  *              name already exists in the namespace, it is overwritten. The
654  *              input buffer must contain a valid DSDT or SSDT containing a
655  *              single control method.
656  *
657  ******************************************************************************/
658 
659 ACPI_STATUS
660 AcpiInstallMethod (
661     UINT8                   *Buffer)
662 {
663     ACPI_TABLE_HEADER       *Table = ACPI_CAST_PTR (ACPI_TABLE_HEADER, Buffer);
664     UINT8                   *AmlBuffer;
665     UINT8                   *AmlStart;
666     char                    *Path;
667     ACPI_NAMESPACE_NODE     *Node;
668     ACPI_OPERAND_OBJECT     *MethodObj;
669     ACPI_PARSE_STATE        ParserState;
670     UINT32                  AmlLength;
671     UINT16                  Opcode;
672     UINT8                   MethodFlags;
673     ACPI_STATUS             Status;
674 
675 
676     /* Parameter validation */
677 
678     if (!Buffer)
679     {
680         return (AE_BAD_PARAMETER);
681     }
682 
683     /* Table must be a DSDT or SSDT */
684 
685     if (!ACPI_COMPARE_NAME (Table->Signature, ACPI_SIG_DSDT) &&
686         !ACPI_COMPARE_NAME (Table->Signature, ACPI_SIG_SSDT))
687     {
688         return (AE_BAD_HEADER);
689     }
690 
691     /* First AML opcode in the table must be a control method */
692 
693     ParserState.Aml = Buffer + sizeof (ACPI_TABLE_HEADER);
694     Opcode = AcpiPsPeekOpcode (&ParserState);
695     if (Opcode != AML_METHOD_OP)
696     {
697         return (AE_BAD_PARAMETER);
698     }
699 
700     /* Extract method information from the raw AML */
701 
702     ParserState.Aml += AcpiPsGetOpcodeSize (Opcode);
703     ParserState.PkgEnd = AcpiPsGetNextPackageEnd (&ParserState);
704     Path = AcpiPsGetNextNamestring (&ParserState);
705     MethodFlags = *ParserState.Aml++;
706     AmlStart = ParserState.Aml;
707     AmlLength = ACPI_PTR_DIFF (ParserState.PkgEnd, AmlStart);
708 
709     /*
710      * Allocate resources up-front. We don't want to have to delete a new
711      * node from the namespace if we cannot allocate memory.
712      */
713     AmlBuffer = ACPI_ALLOCATE (AmlLength);
714     if (!AmlBuffer)
715     {
716         return (AE_NO_MEMORY);
717     }
718 
719     MethodObj = AcpiUtCreateInternalObject (ACPI_TYPE_METHOD);
720     if (!MethodObj)
721     {
722         ACPI_FREE (AmlBuffer);
723         return (AE_NO_MEMORY);
724     }
725 
726     /* Lock namespace for AcpiNsLookup, we may be creating a new node */
727 
728     Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
729     if (ACPI_FAILURE (Status))
730     {
731         goto ErrorExit;
732     }
733 
734     /* The lookup either returns an existing node or creates a new one */
735 
736     Status = AcpiNsLookup (NULL, Path, ACPI_TYPE_METHOD, ACPI_IMODE_LOAD_PASS1,
737                 ACPI_NS_DONT_OPEN_SCOPE | ACPI_NS_ERROR_IF_FOUND, NULL, &Node);
738 
739     (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
740 
741     if (ACPI_FAILURE (Status)) /* NsLookup */
742     {
743         if (Status != AE_ALREADY_EXISTS)
744         {
745             goto ErrorExit;
746         }
747 
748         /* Node existed previously, make sure it is a method node */
749 
750         if (Node->Type != ACPI_TYPE_METHOD)
751         {
752             Status = AE_TYPE;
753             goto ErrorExit;
754         }
755     }
756 
757     /* Copy the method AML to the local buffer */
758 
759     ACPI_MEMCPY (AmlBuffer, AmlStart, AmlLength);
760 
761     /* Initialize the method object with the new method's information */
762 
763     MethodObj->Method.AmlStart = AmlBuffer;
764     MethodObj->Method.AmlLength = AmlLength;
765 
766     MethodObj->Method.ParamCount = (UINT8)
767         (MethodFlags & AML_METHOD_ARG_COUNT);
768 
769     if (MethodFlags & AML_METHOD_SERIALIZED)
770     {
771         MethodObj->Method.InfoFlags = ACPI_METHOD_SERIALIZED;
772 
773         MethodObj->Method.SyncLevel = (UINT8)
774             ((MethodFlags & AML_METHOD_SYNC_LEVEL) >> 4);
775     }
776 
777     /*
778      * Now that it is complete, we can attach the new method object to
779      * the method Node (detaches/deletes any existing object)
780      */
781     Status = AcpiNsAttachObject (Node, MethodObj, ACPI_TYPE_METHOD);
782 
783     /*
784      * Flag indicates AML buffer is dynamic, must be deleted later.
785      * Must be set only after attach above.
786      */
787     Node->Flags |= ANOBJ_ALLOCATED_BUFFER;
788 
789     /* Remove local reference to the method object */
790 
791     AcpiUtRemoveReference (MethodObj);
792     return (Status);
793 
794 
795 ErrorExit:
796 
797     ACPI_FREE (AmlBuffer);
798     ACPI_FREE (MethodObj);
799     return (Status);
800 }
801 
802 ACPI_EXPORT_SYMBOL (AcpiInstallMethod)
803