BPicture: Fix archive constructor.
[haiku.git] / src / add-ons / kernel / bus_managers / acpi / acpica / components / executer / exprep.c
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1 /******************************************************************************
3 * Module Name: exprep - ACPI AML (p-code) execution - field prep utilities
5 *****************************************************************************/
7 /******************************************************************************
9 * 1. Copyright Notice
11 * Some or all of this work - Copyright (c) 1999 - 2014, Intel Corp.
12 * All rights reserved.
14 * 2. License
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.
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
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;
37 * The above copyright and patent license is granted only if the following
38 * conditions are met:
40 * 3. Conditions
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.
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.
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.
72 * 3.4. Intel retains all right, title, and interest in and to the Original
73 * Intel Code.
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.
80 * 4. Disclaimer and Export Compliance
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.
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.
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.
114 *****************************************************************************/
116 #define __EXPREP_C__
118 #include "acpi.h"
119 #include "accommon.h"
120 #include "acinterp.h"
121 #include "amlcode.h"
122 #include "acnamesp.h"
123 #include "acdispat.h"
126 #define _COMPONENT ACPI_EXECUTER
127 ACPI_MODULE_NAME ("exprep")
129 /* Local prototypes */
131 static UINT32
132 AcpiExDecodeFieldAccess (
133 ACPI_OPERAND_OBJECT *ObjDesc,
134 UINT8 FieldFlags,
135 UINT32 *ReturnByteAlignment);
138 #ifdef ACPI_UNDER_DEVELOPMENT
140 static UINT32
141 AcpiExGenerateAccess (
142 UINT32 FieldBitOffset,
143 UINT32 FieldBitLength,
144 UINT32 RegionLength);
146 /*******************************************************************************
148 * FUNCTION: AcpiExGenerateAccess
150 * PARAMETERS: FieldBitOffset - Start of field within parent region/buffer
151 * FieldBitLength - Length of field in bits
152 * RegionLength - Length of parent in bytes
154 * RETURN: Field granularity (8, 16, 32 or 64) and
155 * ByteAlignment (1, 2, 3, or 4)
157 * DESCRIPTION: Generate an optimal access width for fields defined with the
158 * AnyAcc keyword.
160 * NOTE: Need to have the RegionLength in order to check for boundary
161 * conditions (end-of-region). However, the RegionLength is a deferred
162 * operation. Therefore, to complete this implementation, the generation
163 * of this access width must be deferred until the region length has
164 * been evaluated.
166 ******************************************************************************/
168 static UINT32
169 AcpiExGenerateAccess (
170 UINT32 FieldBitOffset,
171 UINT32 FieldBitLength,
172 UINT32 RegionLength)
174 UINT32 FieldByteLength;
175 UINT32 FieldByteOffset;
176 UINT32 FieldByteEndOffset;
177 UINT32 AccessByteWidth;
178 UINT32 FieldStartOffset;
179 UINT32 FieldEndOffset;
180 UINT32 MinimumAccessWidth = 0xFFFFFFFF;
181 UINT32 MinimumAccesses = 0xFFFFFFFF;
182 UINT32 Accesses;
185 ACPI_FUNCTION_TRACE (ExGenerateAccess);
188 /* Round Field start offset and length to "minimal" byte boundaries */
190 FieldByteOffset = ACPI_DIV_8 (ACPI_ROUND_DOWN (FieldBitOffset, 8));
191 FieldByteEndOffset = ACPI_DIV_8 (ACPI_ROUND_UP (FieldBitLength +
192 FieldBitOffset, 8));
193 FieldByteLength = FieldByteEndOffset - FieldByteOffset;
195 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
196 "Bit length %u, Bit offset %u\n",
197 FieldBitLength, FieldBitOffset));
199 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
200 "Byte Length %u, Byte Offset %u, End Offset %u\n",
201 FieldByteLength, FieldByteOffset, FieldByteEndOffset));
204 * Iterative search for the maximum access width that is both aligned
205 * and does not go beyond the end of the region
207 * Start at ByteAcc and work upwards to QwordAcc max. (1,2,4,8 bytes)
209 for (AccessByteWidth = 1; AccessByteWidth <= 8; AccessByteWidth <<= 1)
212 * 1) Round end offset up to next access boundary and make sure that
213 * this does not go beyond the end of the parent region.
214 * 2) When the Access width is greater than the FieldByteLength, we
215 * are done. (This does not optimize for the perfectly aligned
216 * case yet).
218 if (ACPI_ROUND_UP (FieldByteEndOffset, AccessByteWidth) <= RegionLength)
220 FieldStartOffset =
221 ACPI_ROUND_DOWN (FieldByteOffset, AccessByteWidth) /
222 AccessByteWidth;
224 FieldEndOffset =
225 ACPI_ROUND_UP ((FieldByteLength + FieldByteOffset),
226 AccessByteWidth) / AccessByteWidth;
228 Accesses = FieldEndOffset - FieldStartOffset;
230 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
231 "AccessWidth %u end is within region\n", AccessByteWidth));
233 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
234 "Field Start %u, Field End %u -- requires %u accesses\n",
235 FieldStartOffset, FieldEndOffset, Accesses));
237 /* Single access is optimal */
239 if (Accesses <= 1)
241 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
242 "Entire field can be accessed with one operation of size %u\n",
243 AccessByteWidth));
244 return_VALUE (AccessByteWidth);
248 * Fits in the region, but requires more than one read/write.
249 * try the next wider access on next iteration
251 if (Accesses < MinimumAccesses)
253 MinimumAccesses = Accesses;
254 MinimumAccessWidth = AccessByteWidth;
257 else
259 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
260 "AccessWidth %u end is NOT within region\n", AccessByteWidth));
261 if (AccessByteWidth == 1)
263 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
264 "Field goes beyond end-of-region!\n"));
266 /* Field does not fit in the region at all */
268 return_VALUE (0);
272 * This width goes beyond the end-of-region, back off to
273 * previous access
275 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
276 "Backing off to previous optimal access width of %u\n",
277 MinimumAccessWidth));
278 return_VALUE (MinimumAccessWidth);
283 * Could not read/write field with one operation,
284 * just use max access width
286 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
287 "Cannot access field in one operation, using width 8\n"));
288 return_VALUE (8);
290 #endif /* ACPI_UNDER_DEVELOPMENT */
293 /*******************************************************************************
295 * FUNCTION: AcpiExDecodeFieldAccess
297 * PARAMETERS: ObjDesc - Field object
298 * FieldFlags - Encoded fieldflags (contains access bits)
299 * ReturnByteAlignment - Where the byte alignment is returned
301 * RETURN: Field granularity (8, 16, 32 or 64) and
302 * ByteAlignment (1, 2, 3, or 4)
304 * DESCRIPTION: Decode the AccessType bits of a field definition.
306 ******************************************************************************/
308 static UINT32
309 AcpiExDecodeFieldAccess (
310 ACPI_OPERAND_OBJECT *ObjDesc,
311 UINT8 FieldFlags,
312 UINT32 *ReturnByteAlignment)
314 UINT32 Access;
315 UINT32 ByteAlignment;
316 UINT32 BitLength;
319 ACPI_FUNCTION_TRACE (ExDecodeFieldAccess);
322 Access = (FieldFlags & AML_FIELD_ACCESS_TYPE_MASK);
324 switch (Access)
326 case AML_FIELD_ACCESS_ANY:
328 #ifdef ACPI_UNDER_DEVELOPMENT
329 ByteAlignment =
330 AcpiExGenerateAccess (ObjDesc->CommonField.StartFieldBitOffset,
331 ObjDesc->CommonField.BitLength,
332 0xFFFFFFFF /* Temp until we pass RegionLength as parameter */);
333 BitLength = ByteAlignment * 8;
334 #endif
336 ByteAlignment = 1;
337 BitLength = 8;
338 break;
340 case AML_FIELD_ACCESS_BYTE:
341 case AML_FIELD_ACCESS_BUFFER: /* ACPI 2.0 (SMBus Buffer) */
343 ByteAlignment = 1;
344 BitLength = 8;
345 break;
347 case AML_FIELD_ACCESS_WORD:
349 ByteAlignment = 2;
350 BitLength = 16;
351 break;
353 case AML_FIELD_ACCESS_DWORD:
355 ByteAlignment = 4;
356 BitLength = 32;
357 break;
359 case AML_FIELD_ACCESS_QWORD: /* ACPI 2.0 */
361 ByteAlignment = 8;
362 BitLength = 64;
363 break;
365 default:
367 /* Invalid field access type */
369 ACPI_ERROR ((AE_INFO,
370 "Unknown field access type 0x%X",
371 Access));
372 return_UINT32 (0);
375 if (ObjDesc->Common.Type == ACPI_TYPE_BUFFER_FIELD)
378 * BufferField access can be on any byte boundary, so the
379 * ByteAlignment is always 1 byte -- regardless of any ByteAlignment
380 * implied by the field access type.
382 ByteAlignment = 1;
385 *ReturnByteAlignment = ByteAlignment;
386 return_UINT32 (BitLength);
390 /*******************************************************************************
392 * FUNCTION: AcpiExPrepCommonFieldObject
394 * PARAMETERS: ObjDesc - The field object
395 * FieldFlags - Access, LockRule, and UpdateRule.
396 * The format of a FieldFlag is described
397 * in the ACPI specification
398 * FieldAttribute - Special attributes (not used)
399 * FieldBitPosition - Field start position
400 * FieldBitLength - Field length in number of bits
402 * RETURN: Status
404 * DESCRIPTION: Initialize the areas of the field object that are common
405 * to the various types of fields. Note: This is very "sensitive"
406 * code because we are solving the general case for field
407 * alignment.
409 ******************************************************************************/
411 ACPI_STATUS
412 AcpiExPrepCommonFieldObject (
413 ACPI_OPERAND_OBJECT *ObjDesc,
414 UINT8 FieldFlags,
415 UINT8 FieldAttribute,
416 UINT32 FieldBitPosition,
417 UINT32 FieldBitLength)
419 UINT32 AccessBitWidth;
420 UINT32 ByteAlignment;
421 UINT32 NearestByteAddress;
424 ACPI_FUNCTION_TRACE (ExPrepCommonFieldObject);
428 * Note: the structure being initialized is the
429 * ACPI_COMMON_FIELD_INFO; No structure fields outside of the common
430 * area are initialized by this procedure.
432 ObjDesc->CommonField.FieldFlags = FieldFlags;
433 ObjDesc->CommonField.Attribute = FieldAttribute;
434 ObjDesc->CommonField.BitLength = FieldBitLength;
437 * Decode the access type so we can compute offsets. The access type gives
438 * two pieces of information - the width of each field access and the
439 * necessary ByteAlignment (address granularity) of the access.
441 * For AnyAcc, the AccessBitWidth is the largest width that is both
442 * necessary and possible in an attempt to access the whole field in one
443 * I/O operation. However, for AnyAcc, the ByteAlignment is always one
444 * byte.
446 * For all Buffer Fields, the ByteAlignment is always one byte.
448 * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is
449 * the same (equivalent) as the ByteAlignment.
451 AccessBitWidth = AcpiExDecodeFieldAccess (ObjDesc, FieldFlags,
452 &ByteAlignment);
453 if (!AccessBitWidth)
455 return_ACPI_STATUS (AE_AML_OPERAND_VALUE);
458 /* Setup width (access granularity) fields (values are: 1, 2, 4, 8) */
460 ObjDesc->CommonField.AccessByteWidth = (UINT8)
461 ACPI_DIV_8 (AccessBitWidth);
464 * BaseByteOffset is the address of the start of the field within the
465 * region. It is the byte address of the first *datum* (field-width data
466 * unit) of the field. (i.e., the first datum that contains at least the
467 * first *bit* of the field.)
469 * Note: ByteAlignment is always either equal to the AccessBitWidth or 8
470 * (Byte access), and it defines the addressing granularity of the parent
471 * region or buffer.
473 NearestByteAddress =
474 ACPI_ROUND_BITS_DOWN_TO_BYTES (FieldBitPosition);
475 ObjDesc->CommonField.BaseByteOffset = (UINT32)
476 ACPI_ROUND_DOWN (NearestByteAddress, ByteAlignment);
479 * StartFieldBitOffset is the offset of the first bit of the field within
480 * a field datum.
482 ObjDesc->CommonField.StartFieldBitOffset = (UINT8)
483 (FieldBitPosition - ACPI_MUL_8 (ObjDesc->CommonField.BaseByteOffset));
485 return_ACPI_STATUS (AE_OK);
489 /*******************************************************************************
491 * FUNCTION: AcpiExPrepFieldValue
493 * PARAMETERS: Info - Contains all field creation info
495 * RETURN: Status
497 * DESCRIPTION: Construct an object of type ACPI_OPERAND_OBJECT with a
498 * subtype of DefField and connect it to the parent Node.
500 ******************************************************************************/
502 ACPI_STATUS
503 AcpiExPrepFieldValue (
504 ACPI_CREATE_FIELD_INFO *Info)
506 ACPI_OPERAND_OBJECT *ObjDesc;
507 ACPI_OPERAND_OBJECT *SecondDesc = NULL;
508 ACPI_STATUS Status;
509 UINT32 AccessByteWidth;
510 UINT32 Type;
513 ACPI_FUNCTION_TRACE (ExPrepFieldValue);
516 /* Parameter validation */
518 if (Info->FieldType != ACPI_TYPE_LOCAL_INDEX_FIELD)
520 if (!Info->RegionNode)
522 ACPI_ERROR ((AE_INFO, "Null RegionNode"));
523 return_ACPI_STATUS (AE_AML_NO_OPERAND);
526 Type = AcpiNsGetType (Info->RegionNode);
527 if (Type != ACPI_TYPE_REGION)
529 ACPI_ERROR ((AE_INFO, "Needed Region, found type 0x%X (%s)",
530 Type, AcpiUtGetTypeName (Type)));
532 return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
536 /* Allocate a new field object */
538 ObjDesc = AcpiUtCreateInternalObject (Info->FieldType);
539 if (!ObjDesc)
541 return_ACPI_STATUS (AE_NO_MEMORY);
544 /* Initialize areas of the object that are common to all fields */
546 ObjDesc->CommonField.Node = Info->FieldNode;
547 Status = AcpiExPrepCommonFieldObject (ObjDesc,
548 Info->FieldFlags, Info->Attribute,
549 Info->FieldBitPosition, Info->FieldBitLength);
550 if (ACPI_FAILURE (Status))
552 AcpiUtDeleteObjectDesc (ObjDesc);
553 return_ACPI_STATUS (Status);
556 /* Initialize areas of the object that are specific to the field type */
558 switch (Info->FieldType)
560 case ACPI_TYPE_LOCAL_REGION_FIELD:
562 ObjDesc->Field.RegionObj = AcpiNsGetAttachedObject (Info->RegionNode);
564 /* Fields specific to GenericSerialBus fields */
566 ObjDesc->Field.AccessLength = Info->AccessLength;
568 if (Info->ConnectionNode)
570 SecondDesc = Info->ConnectionNode->Object;
571 if (!(SecondDesc->Common.Flags & AOPOBJ_DATA_VALID))
573 Status = AcpiDsGetBufferArguments (SecondDesc);
574 if (ACPI_FAILURE (Status))
576 AcpiUtDeleteObjectDesc (ObjDesc);
577 return_ACPI_STATUS (Status);
581 ObjDesc->Field.ResourceBuffer = SecondDesc->Buffer.Pointer;
582 ObjDesc->Field.ResourceLength = (UINT16) SecondDesc->Buffer.Length;
584 else if (Info->ResourceBuffer)
586 ObjDesc->Field.ResourceBuffer = Info->ResourceBuffer;
587 ObjDesc->Field.ResourceLength = Info->ResourceLength;
590 /* Allow full data read from EC address space */
592 if ((ObjDesc->Field.RegionObj->Region.SpaceId == ACPI_ADR_SPACE_EC) &&
593 (ObjDesc->CommonField.BitLength > 8))
595 AccessByteWidth = ACPI_ROUND_BITS_UP_TO_BYTES (
596 ObjDesc->CommonField.BitLength);
598 /* Maximum byte width supported is 255 */
600 if (AccessByteWidth < 256)
602 ObjDesc->CommonField.AccessByteWidth = (UINT8) AccessByteWidth;
606 /* An additional reference for the container */
608 AcpiUtAddReference (ObjDesc->Field.RegionObj);
610 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
611 "RegionField: BitOff %X, Off %X, Gran %X, Region %p\n",
612 ObjDesc->Field.StartFieldBitOffset, ObjDesc->Field.BaseByteOffset,
613 ObjDesc->Field.AccessByteWidth, ObjDesc->Field.RegionObj));
614 break;
616 case ACPI_TYPE_LOCAL_BANK_FIELD:
618 ObjDesc->BankField.Value = Info->BankValue;
619 ObjDesc->BankField.RegionObj =
620 AcpiNsGetAttachedObject (Info->RegionNode);
621 ObjDesc->BankField.BankObj =
622 AcpiNsGetAttachedObject (Info->RegisterNode);
624 /* An additional reference for the attached objects */
626 AcpiUtAddReference (ObjDesc->BankField.RegionObj);
627 AcpiUtAddReference (ObjDesc->BankField.BankObj);
629 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
630 "Bank Field: BitOff %X, Off %X, Gran %X, Region %p, BankReg %p\n",
631 ObjDesc->BankField.StartFieldBitOffset,
632 ObjDesc->BankField.BaseByteOffset,
633 ObjDesc->Field.AccessByteWidth,
634 ObjDesc->BankField.RegionObj,
635 ObjDesc->BankField.BankObj));
638 * Remember location in AML stream of the field unit
639 * opcode and operands -- since the BankValue
640 * operands must be evaluated.
642 SecondDesc = ObjDesc->Common.NextObject;
643 SecondDesc->Extra.AmlStart = ACPI_CAST_PTR (ACPI_PARSE_OBJECT,
644 Info->DataRegisterNode)->Named.Data;
645 SecondDesc->Extra.AmlLength = ACPI_CAST_PTR (ACPI_PARSE_OBJECT,
646 Info->DataRegisterNode)->Named.Length;
648 break;
650 case ACPI_TYPE_LOCAL_INDEX_FIELD:
652 /* Get the Index and Data registers */
654 ObjDesc->IndexField.IndexObj =
655 AcpiNsGetAttachedObject (Info->RegisterNode);
656 ObjDesc->IndexField.DataObj =
657 AcpiNsGetAttachedObject (Info->DataRegisterNode);
659 if (!ObjDesc->IndexField.DataObj || !ObjDesc->IndexField.IndexObj)
661 ACPI_ERROR ((AE_INFO, "Null Index Object during field prep"));
662 AcpiUtDeleteObjectDesc (ObjDesc);
663 return_ACPI_STATUS (AE_AML_INTERNAL);
666 /* An additional reference for the attached objects */
668 AcpiUtAddReference (ObjDesc->IndexField.DataObj);
669 AcpiUtAddReference (ObjDesc->IndexField.IndexObj);
672 * April 2006: Changed to match MS behavior
674 * The value written to the Index register is the byte offset of the
675 * target field in units of the granularity of the IndexField
677 * Previously, the value was calculated as an index in terms of the
678 * width of the Data register, as below:
680 * ObjDesc->IndexField.Value = (UINT32)
681 * (Info->FieldBitPosition / ACPI_MUL_8 (
682 * ObjDesc->Field.AccessByteWidth));
684 * February 2006: Tried value as a byte offset:
685 * ObjDesc->IndexField.Value = (UINT32)
686 * ACPI_DIV_8 (Info->FieldBitPosition);
688 ObjDesc->IndexField.Value = (UINT32) ACPI_ROUND_DOWN (
689 ACPI_DIV_8 (Info->FieldBitPosition),
690 ObjDesc->IndexField.AccessByteWidth);
692 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
693 "IndexField: BitOff %X, Off %X, Value %X, Gran %X, Index %p, Data %p\n",
694 ObjDesc->IndexField.StartFieldBitOffset,
695 ObjDesc->IndexField.BaseByteOffset,
696 ObjDesc->IndexField.Value,
697 ObjDesc->Field.AccessByteWidth,
698 ObjDesc->IndexField.IndexObj,
699 ObjDesc->IndexField.DataObj));
700 break;
702 default:
704 /* No other types should get here */
706 break;
710 * Store the constructed descriptor (ObjDesc) into the parent Node,
711 * preserving the current type of that NamedObj.
713 Status = AcpiNsAttachObject (Info->FieldNode, ObjDesc,
714 AcpiNsGetType (Info->FieldNode));
716 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Set NamedObj %p [%4.4s], ObjDesc %p\n",
717 Info->FieldNode, AcpiUtGetNodeName (Info->FieldNode), ObjDesc));
719 /* Remove local reference to the object */
721 AcpiUtRemoveReference (ObjDesc);
722 return_ACPI_STATUS (Status);