1 2/****************************************************************************** 3 * 4 * Module Name: exprep - ACPI AML (p-code) execution - field prep utilities 5 * 6 *****************************************************************************/ 7 8/* 9 * Copyright (C) 2000 - 2010, Intel Corp. 10 * All rights reserved. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions, and the following disclaimer, 17 * without modification. 18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 19 * substantially similar to the "NO WARRANTY" disclaimer below 20 * ("Disclaimer") and any redistribution must be conditioned upon 21 * including a substantially similar Disclaimer requirement for further 22 * binary redistribution. 23 * 3. Neither the names of the above-listed copyright holders nor the names 24 * of any contributors may be used to endorse or promote products derived 25 * from this software without specific prior written permission. 26 * 27 * Alternatively, this software may be distributed under the terms of the 28 * GNU General Public License ("GPL") version 2 as published by the Free 29 * Software Foundation. 30 * 31 * NO WARRANTY 32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR 35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 36 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 40 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 41 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 42 * POSSIBILITY OF SUCH DAMAGES. 43 */ 44 45#include <acpi/acpi.h> 46#include "accommon.h" 47#include "acinterp.h" 48#include "amlcode.h" 49#include "acnamesp.h" 50 51#define _COMPONENT ACPI_EXECUTER 52ACPI_MODULE_NAME("exprep") 53 54/* Local prototypes */ 55static u32 56acpi_ex_decode_field_access(union acpi_operand_object *obj_desc, 57 u8 field_flags, u32 * return_byte_alignment); 58 59#ifdef ACPI_UNDER_DEVELOPMENT 60 61static u32 62acpi_ex_generate_access(u32 field_bit_offset, 63 u32 field_bit_length, u32 region_length); 64 65/******************************************************************************* 66 * 67 * FUNCTION: acpi_ex_generate_access 68 * 69 * PARAMETERS: field_bit_offset - Start of field within parent region/buffer 70 * field_bit_length - Length of field in bits 71 * region_length - Length of parent in bytes 72 * 73 * RETURN: Field granularity (8, 16, 32 or 64) and 74 * byte_alignment (1, 2, 3, or 4) 75 * 76 * DESCRIPTION: Generate an optimal access width for fields defined with the 77 * any_acc keyword. 78 * 79 * NOTE: Need to have the region_length in order to check for boundary 80 * conditions (end-of-region). However, the region_length is a deferred 81 * operation. Therefore, to complete this implementation, the generation 82 * of this access width must be deferred until the region length has 83 * been evaluated. 84 * 85 ******************************************************************************/ 86 87static u32 88acpi_ex_generate_access(u32 field_bit_offset, 89 u32 field_bit_length, u32 region_length) 90{ 91 u32 field_byte_length; 92 u32 field_byte_offset; 93 u32 field_byte_end_offset; 94 u32 access_byte_width; 95 u32 field_start_offset; 96 u32 field_end_offset; 97 u32 minimum_access_width = 0xFFFFFFFF; 98 u32 minimum_accesses = 0xFFFFFFFF; 99 u32 accesses; 100 101 ACPI_FUNCTION_TRACE(ex_generate_access); 102 103 /* Round Field start offset and length to "minimal" byte boundaries */ 104 105 field_byte_offset = ACPI_DIV_8(ACPI_ROUND_DOWN(field_bit_offset, 8)); 106 field_byte_end_offset = ACPI_DIV_8(ACPI_ROUND_UP(field_bit_length + 107 field_bit_offset, 8)); 108 field_byte_length = field_byte_end_offset - field_byte_offset; 109 110 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 111 "Bit length %u, Bit offset %u\n", 112 field_bit_length, field_bit_offset)); 113 114 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 115 "Byte Length %u, Byte Offset %u, End Offset %u\n", 116 field_byte_length, field_byte_offset, 117 field_byte_end_offset)); 118 119 /* 120 * Iterative search for the maximum access width that is both aligned 121 * and does not go beyond the end of the region 122 * 123 * Start at byte_acc and work upwards to qword_acc max. (1,2,4,8 bytes) 124 */ 125 for (access_byte_width = 1; access_byte_width <= 8; 126 access_byte_width <<= 1) { 127 /* 128 * 1) Round end offset up to next access boundary and make sure that 129 * this does not go beyond the end of the parent region. 130 * 2) When the Access width is greater than the field_byte_length, we 131 * are done. (This does not optimize for the perfectly aligned 132 * case yet). 133 */ 134 if (ACPI_ROUND_UP(field_byte_end_offset, access_byte_width) <= 135 region_length) { 136 field_start_offset = 137 ACPI_ROUND_DOWN(field_byte_offset, 138 access_byte_width) / 139 access_byte_width; 140 141 field_end_offset = 142 ACPI_ROUND_UP((field_byte_length + 143 field_byte_offset), 144 access_byte_width) / 145 access_byte_width; 146 147 accesses = field_end_offset - field_start_offset; 148 149 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 150 "AccessWidth %u end is within region\n", 151 access_byte_width)); 152 153 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 154 "Field Start %u, Field End %u -- requires %u accesses\n", 155 field_start_offset, field_end_offset, 156 accesses)); 157 158 /* Single access is optimal */ 159 160 if (accesses <= 1) { 161 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 162 "Entire field can be accessed with one operation of size %u\n", 163 access_byte_width)); 164 return_VALUE(access_byte_width); 165 } 166 167 /* 168 * Fits in the region, but requires more than one read/write. 169 * try the next wider access on next iteration 170 */ 171 if (accesses < minimum_accesses) { 172 minimum_accesses = accesses; 173 minimum_access_width = access_byte_width; 174 } 175 } else { 176 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 177 "AccessWidth %u end is NOT within region\n", 178 access_byte_width)); 179 if (access_byte_width == 1) { 180 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 181 "Field goes beyond end-of-region!\n")); 182 183 /* Field does not fit in the region at all */ 184 185 return_VALUE(0); 186 } 187 188 /* 189 * This width goes beyond the end-of-region, back off to 190 * previous access 191 */ 192 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 193 "Backing off to previous optimal access width of %u\n", 194 minimum_access_width)); 195 return_VALUE(minimum_access_width); 196 } 197 } 198 199 /* 200 * Could not read/write field with one operation, 201 * just use max access width 202 */ 203 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 204 "Cannot access field in one operation, using width 8\n")); 205 return_VALUE(8); 206} 207#endif /* ACPI_UNDER_DEVELOPMENT */ 208 209/******************************************************************************* 210 * 211 * FUNCTION: acpi_ex_decode_field_access 212 * 213 * PARAMETERS: obj_desc - Field object 214 * field_flags - Encoded fieldflags (contains access bits) 215 * return_byte_alignment - Where the byte alignment is returned 216 * 217 * RETURN: Field granularity (8, 16, 32 or 64) and 218 * byte_alignment (1, 2, 3, or 4) 219 * 220 * DESCRIPTION: Decode the access_type bits of a field definition. 221 * 222 ******************************************************************************/ 223 224static u32 225acpi_ex_decode_field_access(union acpi_operand_object *obj_desc, 226 u8 field_flags, u32 * return_byte_alignment) 227{ 228 u32 access; 229 u32 byte_alignment; 230 u32 bit_length; 231 232 ACPI_FUNCTION_TRACE(ex_decode_field_access); 233 234 access = (field_flags & AML_FIELD_ACCESS_TYPE_MASK); 235 236 switch (access) { 237 case AML_FIELD_ACCESS_ANY: 238 239#ifdef ACPI_UNDER_DEVELOPMENT 240 byte_alignment = 241 acpi_ex_generate_access(obj_desc->common_field. 242 start_field_bit_offset, 243 obj_desc->common_field.bit_length, 244 0xFFFFFFFF 245 /* Temp until we pass region_length as parameter */ 246 ); 247 bit_length = byte_alignment * 8; 248#endif 249 250 byte_alignment = 1; 251 bit_length = 8; 252 break; 253 254 case AML_FIELD_ACCESS_BYTE: 255 case AML_FIELD_ACCESS_BUFFER: /* ACPI 2.0 (SMBus Buffer) */ 256 byte_alignment = 1; 257 bit_length = 8; 258 break; 259 260 case AML_FIELD_ACCESS_WORD: 261 byte_alignment = 2; 262 bit_length = 16; 263 break; 264 265 case AML_FIELD_ACCESS_DWORD: 266 byte_alignment = 4; 267 bit_length = 32; 268 break; 269 270 case AML_FIELD_ACCESS_QWORD: /* ACPI 2.0 */ 271 byte_alignment = 8; 272 bit_length = 64; 273 break; 274 275 default: 276 /* Invalid field access type */ 277 278 ACPI_ERROR((AE_INFO, "Unknown field access type 0x%X", access)); 279 return_UINT32(0); 280 } 281 282 if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) { 283 /* 284 * buffer_field access can be on any byte boundary, so the 285 * byte_alignment is always 1 byte -- regardless of any byte_alignment 286 * implied by the field access type. 287 */ 288 byte_alignment = 1; 289 } 290 291 *return_byte_alignment = byte_alignment; 292 return_UINT32(bit_length); 293} 294 295/******************************************************************************* 296 * 297 * FUNCTION: acpi_ex_prep_common_field_object 298 * 299 * PARAMETERS: obj_desc - The field object 300 * field_flags - Access, lock_rule, and update_rule. 301 * The format of a field_flag is described 302 * in the ACPI specification 303 * field_attribute - Special attributes (not used) 304 * field_bit_position - Field start position 305 * field_bit_length - Field length in number of bits 306 * 307 * RETURN: Status 308 * 309 * DESCRIPTION: Initialize the areas of the field object that are common 310 * to the various types of fields. Note: This is very "sensitive" 311 * code because we are solving the general case for field 312 * alignment. 313 * 314 ******************************************************************************/ 315 316acpi_status 317acpi_ex_prep_common_field_object(union acpi_operand_object *obj_desc, 318 u8 field_flags, 319 u8 field_attribute, 320 u32 field_bit_position, u32 field_bit_length) 321{ 322 u32 access_bit_width; 323 u32 byte_alignment; 324 u32 nearest_byte_address; 325 326 ACPI_FUNCTION_TRACE(ex_prep_common_field_object); 327 328 /* 329 * Note: the structure being initialized is the 330 * ACPI_COMMON_FIELD_INFO; No structure fields outside of the common 331 * area are initialized by this procedure. 332 */ 333 obj_desc->common_field.field_flags = field_flags; 334 obj_desc->common_field.attribute = field_attribute; 335 obj_desc->common_field.bit_length = field_bit_length; 336 337 /* 338 * Decode the access type so we can compute offsets. The access type gives 339 * two pieces of information - the width of each field access and the 340 * necessary byte_alignment (address granularity) of the access. 341 * 342 * For any_acc, the access_bit_width is the largest width that is both 343 * necessary and possible in an attempt to access the whole field in one 344 * I/O operation. However, for any_acc, the byte_alignment is always one 345 * byte. 346 * 347 * For all Buffer Fields, the byte_alignment is always one byte. 348 * 349 * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is 350 * the same (equivalent) as the byte_alignment. 351 */ 352 access_bit_width = acpi_ex_decode_field_access(obj_desc, field_flags, 353 &byte_alignment); 354 if (!access_bit_width) { 355 return_ACPI_STATUS(AE_AML_OPERAND_VALUE); 356 } 357 358 /* Setup width (access granularity) fields */ 359 360 obj_desc->common_field.access_byte_width = (u8) 361 ACPI_DIV_8(access_bit_width); /* 1, 2, 4, 8 */ 362 363 obj_desc->common_field.access_bit_width = (u8) access_bit_width; 364 365 /* 366 * base_byte_offset is the address of the start of the field within the 367 * region. It is the byte address of the first *datum* (field-width data 368 * unit) of the field. (i.e., the first datum that contains at least the 369 * first *bit* of the field.) 370 * 371 * Note: byte_alignment is always either equal to the access_bit_width or 8 372 * (Byte access), and it defines the addressing granularity of the parent 373 * region or buffer. 374 */ 375 nearest_byte_address = 376 ACPI_ROUND_BITS_DOWN_TO_BYTES(field_bit_position); 377 obj_desc->common_field.base_byte_offset = (u32) 378 ACPI_ROUND_DOWN(nearest_byte_address, byte_alignment); 379 380 /* 381 * start_field_bit_offset is the offset of the first bit of the field within 382 * a field datum. 383 */ 384 obj_desc->common_field.start_field_bit_offset = (u8) 385 (field_bit_position - 386 ACPI_MUL_8(obj_desc->common_field.base_byte_offset)); 387 388 return_ACPI_STATUS(AE_OK); 389} 390 391/******************************************************************************* 392 * 393 * FUNCTION: acpi_ex_prep_field_value 394 * 395 * PARAMETERS: Info - Contains all field creation info 396 * 397 * RETURN: Status 398 * 399 * DESCRIPTION: Construct a union acpi_operand_object of type def_field and 400 * connect it to the parent Node. 401 * 402 ******************************************************************************/ 403 404acpi_status acpi_ex_prep_field_value(struct acpi_create_field_info *info) 405{ 406 union acpi_operand_object *obj_desc; 407 union acpi_operand_object *second_desc = NULL; 408 u32 type; 409 acpi_status status; 410 411 ACPI_FUNCTION_TRACE(ex_prep_field_value); 412 413 /* Parameter validation */ 414 415 if (info->field_type != ACPI_TYPE_LOCAL_INDEX_FIELD) { 416 if (!info->region_node) { 417 ACPI_ERROR((AE_INFO, "Null RegionNode")); 418 return_ACPI_STATUS(AE_AML_NO_OPERAND); 419 } 420 421 type = acpi_ns_get_type(info->region_node); 422 if (type != ACPI_TYPE_REGION) { 423 ACPI_ERROR((AE_INFO, 424 "Needed Region, found type 0x%X (%s)", 425 type, acpi_ut_get_type_name(type))); 426 427 return_ACPI_STATUS(AE_AML_OPERAND_TYPE); 428 } 429 } 430 431 /* Allocate a new field object */ 432 433 obj_desc = acpi_ut_create_internal_object(info->field_type); 434 if (!obj_desc) { 435 return_ACPI_STATUS(AE_NO_MEMORY); 436 } 437 438 /* Initialize areas of the object that are common to all fields */ 439 440 obj_desc->common_field.node = info->field_node; 441 status = acpi_ex_prep_common_field_object(obj_desc, info->field_flags, 442 info->attribute, 443 info->field_bit_position, 444 info->field_bit_length); 445 if (ACPI_FAILURE(status)) { 446 acpi_ut_delete_object_desc(obj_desc); 447 return_ACPI_STATUS(status); 448 } 449 450 /* Initialize areas of the object that are specific to the field type */ 451 452 switch (info->field_type) { 453 case ACPI_TYPE_LOCAL_REGION_FIELD: 454 455 obj_desc->field.region_obj = 456 acpi_ns_get_attached_object(info->region_node); 457 458 /* An additional reference for the container */ 459 460 acpi_ut_add_reference(obj_desc->field.region_obj); 461 462 /* allow full data read from EC address space */ 463 if (obj_desc->field.region_obj->region.space_id == 464 ACPI_ADR_SPACE_EC) { 465 if (obj_desc->common_field.bit_length > 8) { 466 unsigned width = 467 ACPI_ROUND_BITS_UP_TO_BYTES( 468 obj_desc->common_field.bit_length); 469 // access_bit_width is u8, don't overflow it 470 if (width > 8) 471 width = 8; 472 obj_desc->common_field.access_byte_width = 473 width; 474 obj_desc->common_field.access_bit_width = 475 8 * width; 476 } 477 } 478 479 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 480 "RegionField: BitOff %X, Off %X, Gran %X, Region %p\n", 481 obj_desc->field.start_field_bit_offset, 482 obj_desc->field.base_byte_offset, 483 obj_desc->field.access_byte_width, 484 obj_desc->field.region_obj)); 485 break; 486 487 case ACPI_TYPE_LOCAL_BANK_FIELD: 488 489 obj_desc->bank_field.value = info->bank_value; 490 obj_desc->bank_field.region_obj = 491 acpi_ns_get_attached_object(info->region_node); 492 obj_desc->bank_field.bank_obj = 493 acpi_ns_get_attached_object(info->register_node); 494 495 /* An additional reference for the attached objects */ 496 497 acpi_ut_add_reference(obj_desc->bank_field.region_obj); 498 acpi_ut_add_reference(obj_desc->bank_field.bank_obj); 499 500 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 501 "Bank Field: BitOff %X, Off %X, Gran %X, Region %p, BankReg %p\n", 502 obj_desc->bank_field.start_field_bit_offset, 503 obj_desc->bank_field.base_byte_offset, 504 obj_desc->field.access_byte_width, 505 obj_desc->bank_field.region_obj, 506 obj_desc->bank_field.bank_obj)); 507 508 /* 509 * Remember location in AML stream of the field unit 510 * opcode and operands -- since the bank_value 511 * operands must be evaluated. 512 */ 513 second_desc = obj_desc->common.next_object; 514 second_desc->extra.aml_start = 515 ACPI_CAST_PTR(union acpi_parse_object, 516 info->data_register_node)->named.data; 517 second_desc->extra.aml_length = 518 ACPI_CAST_PTR(union acpi_parse_object, 519 info->data_register_node)->named.length; 520 521 break; 522 523 case ACPI_TYPE_LOCAL_INDEX_FIELD: 524 525 /* Get the Index and Data registers */ 526 527 obj_desc->index_field.index_obj = 528 acpi_ns_get_attached_object(info->register_node); 529 obj_desc->index_field.data_obj = 530 acpi_ns_get_attached_object(info->data_register_node); 531 532 if (!obj_desc->index_field.data_obj 533 || !obj_desc->index_field.index_obj) { 534 ACPI_ERROR((AE_INFO, 535 "Null Index Object during field prep")); 536 acpi_ut_delete_object_desc(obj_desc); 537 return_ACPI_STATUS(AE_AML_INTERNAL); 538 } 539 540 /* An additional reference for the attached objects */ 541 542 acpi_ut_add_reference(obj_desc->index_field.data_obj); 543 acpi_ut_add_reference(obj_desc->index_field.index_obj); 544 545 /* 546 * April 2006: Changed to match MS behavior 547 * 548 * The value written to the Index register is the byte offset of the 549 * target field in units of the granularity of the index_field 550 * 551 * Previously, the value was calculated as an index in terms of the 552 * width of the Data register, as below: 553 * 554 * obj_desc->index_field.Value = (u32) 555 * (Info->field_bit_position / ACPI_MUL_8 ( 556 * obj_desc->Field.access_byte_width)); 557 * 558 * February 2006: Tried value as a byte offset: 559 * obj_desc->index_field.Value = (u32) 560 * ACPI_DIV_8 (Info->field_bit_position); 561 */ 562 obj_desc->index_field.value = 563 (u32) ACPI_ROUND_DOWN(ACPI_DIV_8(info->field_bit_position), 564 obj_desc->index_field. 565 access_byte_width); 566 567 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 568 "IndexField: BitOff %X, Off %X, Value %X, Gran %X, Index %p, Data %p\n", 569 obj_desc->index_field.start_field_bit_offset, 570 obj_desc->index_field.base_byte_offset, 571 obj_desc->index_field.value, 572 obj_desc->field.access_byte_width, 573 obj_desc->index_field.index_obj, 574 obj_desc->index_field.data_obj)); 575 break; 576 577 default: 578 /* No other types should get here */ 579 break; 580 } 581 582 /* 583 * Store the constructed descriptor (obj_desc) into the parent Node, 584 * preserving the current type of that named_obj. 585 */ 586 status = acpi_ns_attach_object(info->field_node, obj_desc, 587 acpi_ns_get_type(info->field_node)); 588 589 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, 590 "Set NamedObj %p [%4.4s], ObjDesc %p\n", 591 info->field_node, 592 acpi_ut_get_node_name(info->field_node), obj_desc)); 593 594 /* Remove local reference to the object */ 595 596 acpi_ut_remove_reference(obj_desc); 597 return_ACPI_STATUS(status); 598} 599