1 2 /****************************************************************************** 3 * 4 * Module Name: exprep - ACPI AML (p-code) execution - field prep utilities 5 * $Revision: 1.144 $ 6 * 7 *****************************************************************************/ 8 9 /****************************************************************************** 10 * 11 * 1. Copyright Notice 12 * 13 * Some or all of this work - Copyright (c) 1999 - 2008, Intel Corp. 14 * All rights reserved. 15 * 16 * 2. License 17 * 18 * 2.1. This is your license from Intel Corp. under its intellectual property 19 * rights. You may have additional license terms from the party that provided 20 * you this software, covering your right to use that party's intellectual 21 * property rights. 22 * 23 * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a 24 * copy of the source code appearing in this file ("Covered Code") an 25 * irrevocable, perpetual, worldwide license under Intel's copyrights in the 26 * base code distributed originally by Intel ("Original Intel Code") to copy, 27 * make derivatives, distribute, use and display any portion of the Covered 28 * Code in any form, with the right to sublicense such rights; and 29 * 30 * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent 31 * license (with the right to sublicense), under only those claims of Intel 32 * patents that are infringed by the Original Intel Code, to make, use, sell, 33 * offer to sell, and import the Covered Code and derivative works thereof 34 * solely to the minimum extent necessary to exercise the above copyright 35 * license, and in no event shall the patent license extend to any additions 36 * to or modifications of the Original Intel Code. No other license or right 37 * is granted directly or by implication, estoppel or otherwise; 38 * 39 * The above copyright and patent license is granted only if the following 40 * conditions are met: 41 * 42 * 3. Conditions 43 * 44 * 3.1. Redistribution of Source with Rights to Further Distribute Source. 45 * Redistribution of source code of any substantial portion of the Covered 46 * Code or modification with rights to further distribute source must include 47 * the above Copyright Notice, the above License, this list of Conditions, 48 * and the following Disclaimer and Export Compliance provision. In addition, 49 * Licensee must cause all Covered Code to which Licensee contributes to 50 * contain a file documenting the changes Licensee made to create that Covered 51 * Code and the date of any change. Licensee must include in that file the 52 * documentation of any changes made by any predecessor Licensee. Licensee 53 * must include a prominent statement that the modification is derived, 54 * directly or indirectly, from Original Intel Code. 55 * 56 * 3.2. Redistribution of Source with no Rights to Further Distribute Source. 57 * Redistribution of source code of any substantial portion of the Covered 58 * Code or modification without rights to further distribute source must 59 * include the following Disclaimer and Export Compliance provision in the 60 * documentation and/or other materials provided with distribution. In 61 * addition, Licensee may not authorize further sublicense of source of any 62 * portion of the Covered Code, and must include terms to the effect that the 63 * license from Licensee to its licensee is limited to the intellectual 64 * property embodied in the software Licensee provides to its licensee, and 65 * not to intellectual property embodied in modifications its licensee may 66 * make. 67 * 68 * 3.3. Redistribution of Executable. Redistribution in executable form of any 69 * substantial portion of the Covered Code or modification must reproduce the 70 * above Copyright Notice, and the following Disclaimer and Export Compliance 71 * provision in the documentation and/or other materials provided with the 72 * distribution. 73 * 74 * 3.4. Intel retains all right, title, and interest in and to the Original 75 * Intel Code. 76 * 77 * 3.5. Neither the name Intel nor any other trademark owned or controlled by 78 * Intel shall be used in advertising or otherwise to promote the sale, use or 79 * other dealings in products derived from or relating to the Covered Code 80 * without prior written authorization from Intel. 81 * 82 * 4. Disclaimer and Export Compliance 83 * 84 * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED 85 * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE 86 * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE, 87 * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY 88 * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY 89 * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A 90 * PARTICULAR PURPOSE. 91 * 92 * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES 93 * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR 94 * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT, 95 * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY 96 * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL 97 * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS 98 * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY 99 * LIMITED REMEDY. 100 * 101 * 4.3. Licensee shall not export, either directly or indirectly, any of this 102 * software or system incorporating such software without first obtaining any 103 * required license or other approval from the U. S. Department of Commerce or 104 * any other agency or department of the United States Government. In the 105 * event Licensee exports any such software from the United States or 106 * re-exports any such software from a foreign destination, Licensee shall 107 * ensure that the distribution and export/re-export of the software is in 108 * compliance with all laws, regulations, orders, or other restrictions of the 109 * U.S. Export Administration Regulations. Licensee agrees that neither it nor 110 * any of its subsidiaries will export/re-export any technical data, process, 111 * software, or service, directly or indirectly, to any country for which the 112 * United States government or any agency thereof requires an export license, 113 * other governmental approval, or letter of assurance, without first obtaining 114 * such license, approval or letter. 115 * 116 *****************************************************************************/ 117 118 #define __EXPREP_C__ 119 120 #include "acpi.h" 121 #include "acinterp.h" 122 #include "amlcode.h" 123 #include "acnamesp.h" 124 125 126 #define _COMPONENT ACPI_EXECUTER 127 ACPI_MODULE_NAME ("exprep") 128 129 /* Local prototypes */ 130 131 static UINT32 132 AcpiExDecodeFieldAccess ( 133 ACPI_OPERAND_OBJECT *ObjDesc, 134 UINT8 FieldFlags, 135 UINT32 *ReturnByteAlignment); 136 137 138 #ifdef ACPI_UNDER_DEVELOPMENT 139 140 static UINT32 141 AcpiExGenerateAccess ( 142 UINT32 FieldBitOffset, 143 UINT32 FieldBitLength, 144 UINT32 RegionLength); 145 146 /******************************************************************************* 147 * 148 * FUNCTION: AcpiExGenerateAccess 149 * 150 * PARAMETERS: FieldBitOffset - Start of field within parent region/buffer 151 * FieldBitLength - Length of field in bits 152 * RegionLength - Length of parent in bytes 153 * 154 * RETURN: Field granularity (8, 16, 32 or 64) and 155 * ByteAlignment (1, 2, 3, or 4) 156 * 157 * DESCRIPTION: Generate an optimal access width for fields defined with the 158 * AnyAcc keyword. 159 * 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. 165 * 166 ******************************************************************************/ 167 168 static UINT32 169 AcpiExGenerateAccess ( 170 UINT32 FieldBitOffset, 171 UINT32 FieldBitLength, 172 UINT32 RegionLength) 173 { 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; 183 184 185 ACPI_FUNCTION_TRACE (ExGenerateAccess); 186 187 188 /* Round Field start offset and length to "minimal" byte boundaries */ 189 190 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; 194 195 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, 196 "Bit length %d, Bit offset %d\n", 197 FieldBitLength, FieldBitOffset)); 198 199 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, 200 "Byte Length %d, Byte Offset %d, End Offset %d\n", 201 FieldByteLength, FieldByteOffset, FieldByteEndOffset)); 202 203 /* 204 * Iterative search for the maximum access width that is both aligned 205 * and does not go beyond the end of the region 206 * 207 * Start at ByteAcc and work upwards to QwordAcc max. (1,2,4,8 bytes) 208 */ 209 for (AccessByteWidth = 1; AccessByteWidth <= 8; AccessByteWidth <<= 1) 210 { 211 /* 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). 217 */ 218 if (ACPI_ROUND_UP (FieldByteEndOffset, AccessByteWidth) <= RegionLength) 219 { 220 FieldStartOffset = 221 ACPI_ROUND_DOWN (FieldByteOffset, AccessByteWidth) / 222 AccessByteWidth; 223 224 FieldEndOffset = 225 ACPI_ROUND_UP ((FieldByteLength + FieldByteOffset), 226 AccessByteWidth) / AccessByteWidth; 227 228 Accesses = FieldEndOffset - FieldStartOffset; 229 230 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, 231 "AccessWidth %d end is within region\n", AccessByteWidth)); 232 233 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, 234 "Field Start %d, Field End %d -- requires %d accesses\n", 235 FieldStartOffset, FieldEndOffset, Accesses)); 236 237 /* Single access is optimal */ 238 239 if (Accesses <= 1) 240 { 241 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, 242 "Entire field can be accessed with one operation of size %d\n", 243 AccessByteWidth)); 244 return_VALUE (AccessByteWidth); 245 } 246 247 /* 248 * Fits in the region, but requires more than one read/write. 249 * try the next wider access on next iteration 250 */ 251 if (Accesses < MinimumAccesses) 252 { 253 MinimumAccesses = Accesses; 254 MinimumAccessWidth = AccessByteWidth; 255 } 256 } 257 else 258 { 259 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, 260 "AccessWidth %d end is NOT within region\n", AccessByteWidth)); 261 if (AccessByteWidth == 1) 262 { 263 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, 264 "Field goes beyond end-of-region!\n")); 265 266 /* Field does not fit in the region at all */ 267 268 return_VALUE (0); 269 } 270 271 /* 272 * This width goes beyond the end-of-region, back off to 273 * previous access 274 */ 275 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, 276 "Backing off to previous optimal access width of %d\n", 277 MinimumAccessWidth)); 278 return_VALUE (MinimumAccessWidth); 279 } 280 } 281 282 /* 283 * Could not read/write field with one operation, 284 * just use max access width 285 */ 286 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, 287 "Cannot access field in one operation, using width 8\n")); 288 return_VALUE (8); 289 } 290 #endif /* ACPI_UNDER_DEVELOPMENT */ 291 292 293 /******************************************************************************* 294 * 295 * FUNCTION: AcpiExDecodeFieldAccess 296 * 297 * PARAMETERS: ObjDesc - Field object 298 * FieldFlags - Encoded fieldflags (contains access bits) 299 * ReturnByteAlignment - Where the byte alignment is returned 300 * 301 * RETURN: Field granularity (8, 16, 32 or 64) and 302 * ByteAlignment (1, 2, 3, or 4) 303 * 304 * DESCRIPTION: Decode the AccessType bits of a field definition. 305 * 306 ******************************************************************************/ 307 308 static UINT32 309 AcpiExDecodeFieldAccess ( 310 ACPI_OPERAND_OBJECT *ObjDesc, 311 UINT8 FieldFlags, 312 UINT32 *ReturnByteAlignment) 313 { 314 UINT32 Access; 315 UINT32 ByteAlignment; 316 UINT32 BitLength; 317 318 319 ACPI_FUNCTION_TRACE (ExDecodeFieldAccess); 320 321 322 Access = (FieldFlags & AML_FIELD_ACCESS_TYPE_MASK); 323 324 switch (Access) 325 { 326 case AML_FIELD_ACCESS_ANY: 327 328 #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 335 336 ByteAlignment = 1; 337 BitLength = 8; 338 break; 339 340 case AML_FIELD_ACCESS_BYTE: 341 case AML_FIELD_ACCESS_BUFFER: /* ACPI 2.0 (SMBus Buffer) */ 342 ByteAlignment = 1; 343 BitLength = 8; 344 break; 345 346 case AML_FIELD_ACCESS_WORD: 347 ByteAlignment = 2; 348 BitLength = 16; 349 break; 350 351 case AML_FIELD_ACCESS_DWORD: 352 ByteAlignment = 4; 353 BitLength = 32; 354 break; 355 356 case AML_FIELD_ACCESS_QWORD: /* ACPI 2.0 */ 357 ByteAlignment = 8; 358 BitLength = 64; 359 break; 360 361 default: 362 /* Invalid field access type */ 363 364 ACPI_ERROR ((AE_INFO, 365 "Unknown field access type %X", 366 Access)); 367 return_UINT32 (0); 368 } 369 370 if (ACPI_GET_OBJECT_TYPE (ObjDesc) == ACPI_TYPE_BUFFER_FIELD) 371 { 372 /* 373 * BufferField access can be on any byte boundary, so the 374 * ByteAlignment is always 1 byte -- regardless of any ByteAlignment 375 * implied by the field access type. 376 */ 377 ByteAlignment = 1; 378 } 379 380 *ReturnByteAlignment = ByteAlignment; 381 return_UINT32 (BitLength); 382 } 383 384 385 /******************************************************************************* 386 * 387 * FUNCTION: AcpiExPrepCommonFieldObject 388 * 389 * PARAMETERS: ObjDesc - The field object 390 * FieldFlags - Access, LockRule, and UpdateRule. 391 * The format of a FieldFlag is described 392 * in the ACPI specification 393 * FieldAttribute - Special attributes (not used) 394 * FieldBitPosition - Field start position 395 * FieldBitLength - Field length in number of bits 396 * 397 * RETURN: Status 398 * 399 * DESCRIPTION: Initialize the areas of the field object that are common 400 * to the various types of fields. Note: This is very "sensitive" 401 * code because we are solving the general case for field 402 * alignment. 403 * 404 ******************************************************************************/ 405 406 ACPI_STATUS 407 AcpiExPrepCommonFieldObject ( 408 ACPI_OPERAND_OBJECT *ObjDesc, 409 UINT8 FieldFlags, 410 UINT8 FieldAttribute, 411 UINT32 FieldBitPosition, 412 UINT32 FieldBitLength) 413 { 414 UINT32 AccessBitWidth; 415 UINT32 ByteAlignment; 416 UINT32 NearestByteAddress; 417 418 419 ACPI_FUNCTION_TRACE (ExPrepCommonFieldObject); 420 421 422 /* 423 * Note: the structure being initialized is the 424 * ACPI_COMMON_FIELD_INFO; No structure fields outside of the common 425 * area are initialized by this procedure. 426 */ 427 ObjDesc->CommonField.FieldFlags = FieldFlags; 428 ObjDesc->CommonField.Attribute = FieldAttribute; 429 ObjDesc->CommonField.BitLength = FieldBitLength; 430 431 /* 432 * Decode the access type so we can compute offsets. The access type gives 433 * two pieces of information - the width of each field access and the 434 * necessary ByteAlignment (address granularity) of the access. 435 * 436 * For AnyAcc, the AccessBitWidth is the largest width that is both 437 * necessary and possible in an attempt to access the whole field in one 438 * I/O operation. However, for AnyAcc, the ByteAlignment is always one 439 * byte. 440 * 441 * For all Buffer Fields, the ByteAlignment is always one byte. 442 * 443 * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is 444 * the same (equivalent) as the ByteAlignment. 445 */ 446 AccessBitWidth = AcpiExDecodeFieldAccess (ObjDesc, FieldFlags, 447 &ByteAlignment); 448 if (!AccessBitWidth) 449 { 450 return_ACPI_STATUS (AE_AML_OPERAND_VALUE); 451 } 452 453 /* Setup width (access granularity) fields */ 454 455 ObjDesc->CommonField.AccessByteWidth = (UINT8) 456 ACPI_DIV_8 (AccessBitWidth); /* 1, 2, 4, 8 */ 457 458 ObjDesc->CommonField.AccessBitWidth = (UINT8) AccessBitWidth; 459 460 /* 461 * BaseByteOffset is the address of the start of the field within the 462 * region. It is the byte address of the first *datum* (field-width data 463 * unit) of the field. (i.e., the first datum that contains at least the 464 * first *bit* of the field.) 465 * 466 * Note: ByteAlignment is always either equal to the AccessBitWidth or 8 467 * (Byte access), and it defines the addressing granularity of the parent 468 * region or buffer. 469 */ 470 NearestByteAddress = 471 ACPI_ROUND_BITS_DOWN_TO_BYTES (FieldBitPosition); 472 ObjDesc->CommonField.BaseByteOffset = (UINT32) 473 ACPI_ROUND_DOWN (NearestByteAddress, ByteAlignment); 474 475 /* 476 * StartFieldBitOffset is the offset of the first bit of the field within 477 * a field datum. 478 */ 479 ObjDesc->CommonField.StartFieldBitOffset = (UINT8) 480 (FieldBitPosition - ACPI_MUL_8 (ObjDesc->CommonField.BaseByteOffset)); 481 482 /* 483 * Does the entire field fit within a single field access element? (datum) 484 * (i.e., without crossing a datum boundary) 485 */ 486 if ((ObjDesc->CommonField.StartFieldBitOffset + FieldBitLength) <= 487 (UINT16) AccessBitWidth) 488 { 489 ObjDesc->Common.Flags |= AOPOBJ_SINGLE_DATUM; 490 } 491 492 return_ACPI_STATUS (AE_OK); 493 } 494 495 496 /******************************************************************************* 497 * 498 * FUNCTION: AcpiExPrepFieldValue 499 * 500 * PARAMETERS: Info - Contains all field creation info 501 * 502 * RETURN: Status 503 * 504 * DESCRIPTION: Construct an ACPI_OPERAND_OBJECT of type DefField and 505 * connect it to the parent Node. 506 * 507 ******************************************************************************/ 508 509 ACPI_STATUS 510 AcpiExPrepFieldValue ( 511 ACPI_CREATE_FIELD_INFO *Info) 512 { 513 ACPI_OPERAND_OBJECT *ObjDesc; 514 ACPI_OPERAND_OBJECT *SecondDesc = NULL; 515 UINT32 Type; 516 ACPI_STATUS Status; 517 518 519 ACPI_FUNCTION_TRACE (ExPrepFieldValue); 520 521 522 /* Parameter validation */ 523 524 if (Info->FieldType != ACPI_TYPE_LOCAL_INDEX_FIELD) 525 { 526 if (!Info->RegionNode) 527 { 528 ACPI_ERROR ((AE_INFO, "Null RegionNode")); 529 return_ACPI_STATUS (AE_AML_NO_OPERAND); 530 } 531 532 Type = AcpiNsGetType (Info->RegionNode); 533 if (Type != ACPI_TYPE_REGION) 534 { 535 ACPI_ERROR ((AE_INFO, 536 "Needed Region, found type %X (%s)", 537 Type, AcpiUtGetTypeName (Type))); 538 539 return_ACPI_STATUS (AE_AML_OPERAND_TYPE); 540 } 541 } 542 543 /* Allocate a new field object */ 544 545 ObjDesc = AcpiUtCreateInternalObject (Info->FieldType); 546 if (!ObjDesc) 547 { 548 return_ACPI_STATUS (AE_NO_MEMORY); 549 } 550 551 /* Initialize areas of the object that are common to all fields */ 552 553 ObjDesc->CommonField.Node = Info->FieldNode; 554 Status = AcpiExPrepCommonFieldObject (ObjDesc, Info->FieldFlags, 555 Info->Attribute, Info->FieldBitPosition, Info->FieldBitLength); 556 if (ACPI_FAILURE (Status)) 557 { 558 AcpiUtDeleteObjectDesc (ObjDesc); 559 return_ACPI_STATUS (Status); 560 } 561 562 /* Initialize areas of the object that are specific to the field type */ 563 564 switch (Info->FieldType) 565 { 566 case ACPI_TYPE_LOCAL_REGION_FIELD: 567 568 ObjDesc->Field.RegionObj = AcpiNsGetAttachedObject (Info->RegionNode); 569 570 /* An additional reference for the container */ 571 572 AcpiUtAddReference (ObjDesc->Field.RegionObj); 573 574 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, 575 "RegionField: BitOff %X, Off %X, Gran %X, Region %p\n", 576 ObjDesc->Field.StartFieldBitOffset, ObjDesc->Field.BaseByteOffset, 577 ObjDesc->Field.AccessByteWidth, ObjDesc->Field.RegionObj)); 578 break; 579 580 581 case ACPI_TYPE_LOCAL_BANK_FIELD: 582 583 ObjDesc->BankField.Value = Info->BankValue; 584 ObjDesc->BankField.RegionObj = AcpiNsGetAttachedObject ( 585 Info->RegionNode); 586 ObjDesc->BankField.BankObj = AcpiNsGetAttachedObject ( 587 Info->RegisterNode); 588 589 /* An additional reference for the attached objects */ 590 591 AcpiUtAddReference (ObjDesc->BankField.RegionObj); 592 AcpiUtAddReference (ObjDesc->BankField.BankObj); 593 594 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, 595 "Bank Field: BitOff %X, Off %X, Gran %X, Region %p, BankReg %p\n", 596 ObjDesc->BankField.StartFieldBitOffset, 597 ObjDesc->BankField.BaseByteOffset, 598 ObjDesc->Field.AccessByteWidth, 599 ObjDesc->BankField.RegionObj, 600 ObjDesc->BankField.BankObj)); 601 602 /* 603 * Remember location in AML stream of the field unit 604 * opcode and operands -- since the BankValue 605 * operands must be evaluated. 606 */ 607 SecondDesc = ObjDesc->Common.NextObject; 608 SecondDesc->Extra.AmlStart = ACPI_CAST_PTR (ACPI_PARSE_OBJECT, Info->DataRegisterNode)->Named.Data; 609 SecondDesc->Extra.AmlLength = ACPI_CAST_PTR (ACPI_PARSE_OBJECT, Info->DataRegisterNode)->Named.Length; 610 611 break; 612 613 614 case ACPI_TYPE_LOCAL_INDEX_FIELD: 615 616 /* Get the Index and Data registers */ 617 618 ObjDesc->IndexField.IndexObj = AcpiNsGetAttachedObject ( 619 Info->RegisterNode); 620 ObjDesc->IndexField.DataObj = AcpiNsGetAttachedObject ( 621 Info->DataRegisterNode); 622 623 if (!ObjDesc->IndexField.DataObj || !ObjDesc->IndexField.IndexObj) 624 { 625 ACPI_ERROR ((AE_INFO, "Null Index Object during field prep")); 626 AcpiUtDeleteObjectDesc (ObjDesc); 627 return_ACPI_STATUS (AE_AML_INTERNAL); 628 } 629 630 /* An additional reference for the attached objects */ 631 632 AcpiUtAddReference (ObjDesc->IndexField.DataObj); 633 AcpiUtAddReference (ObjDesc->IndexField.IndexObj); 634 635 /* 636 * April 2006: Changed to match MS behavior 637 * 638 * The value written to the Index register is the byte offset of the 639 * target field in units of the granularity of the IndexField 640 * 641 * Previously, the value was calculated as an index in terms of the 642 * width of the Data register, as below: 643 * 644 * ObjDesc->IndexField.Value = (UINT32) 645 * (Info->FieldBitPosition / ACPI_MUL_8 ( 646 * ObjDesc->Field.AccessByteWidth)); 647 * 648 * February 2006: Tried value as a byte offset: 649 * ObjDesc->IndexField.Value = (UINT32) 650 * ACPI_DIV_8 (Info->FieldBitPosition); 651 */ 652 ObjDesc->IndexField.Value = (UINT32) ACPI_ROUND_DOWN ( 653 ACPI_DIV_8 (Info->FieldBitPosition), 654 ObjDesc->IndexField.AccessByteWidth); 655 656 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, 657 "IndexField: BitOff %X, Off %X, Value %X, Gran %X, Index %p, Data %p\n", 658 ObjDesc->IndexField.StartFieldBitOffset, 659 ObjDesc->IndexField.BaseByteOffset, 660 ObjDesc->IndexField.Value, 661 ObjDesc->Field.AccessByteWidth, 662 ObjDesc->IndexField.IndexObj, 663 ObjDesc->IndexField.DataObj)); 664 break; 665 666 default: 667 /* No other types should get here */ 668 break; 669 } 670 671 /* 672 * Store the constructed descriptor (ObjDesc) into the parent Node, 673 * preserving the current type of that NamedObj. 674 */ 675 Status = AcpiNsAttachObject (Info->FieldNode, ObjDesc, 676 AcpiNsGetType (Info->FieldNode)); 677 678 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Set NamedObj %p [%4.4s], ObjDesc %p\n", 679 Info->FieldNode, AcpiUtGetNodeName (Info->FieldNode), ObjDesc)); 680 681 /* Remove local reference to the object */ 682 683 AcpiUtRemoveReference (ObjDesc); 684 return_ACPI_STATUS (Status); 685 } 686 687