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1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.02/******************************************************************************3 *4 * Module Name: exprep - ACPI AML field prep utilities5 *6 * Copyright (C) 2000 - 2023, Intel Corp.7 *8 *****************************************************************************/9 10#include <acpi/acpi.h>11#include "accommon.h"12#include "acinterp.h"13#include "amlcode.h"14#include "acnamesp.h"15#include "acdispat.h"16 17#define _COMPONENT ACPI_EXECUTER18ACPI_MODULE_NAME("exprep")19 20/* Local prototypes */21static u3222acpi_ex_decode_field_access(union acpi_operand_object *obj_desc,23 u8 field_flags, u32 * return_byte_alignment);24 25#ifdef ACPI_UNDER_DEVELOPMENT26 27static u3228acpi_ex_generate_access(u32 field_bit_offset,29 u32 field_bit_length, u32 region_length);30 31/*******************************************************************************32 *33 * FUNCTION: acpi_ex_generate_access34 *35 * PARAMETERS: field_bit_offset - Start of field within parent region/buffer36 * field_bit_length - Length of field in bits37 * region_length - Length of parent in bytes38 *39 * RETURN: Field granularity (8, 16, 32 or 64) and40 * byte_alignment (1, 2, 3, or 4)41 *42 * DESCRIPTION: Generate an optimal access width for fields defined with the43 * any_acc keyword.44 *45 * NOTE: Need to have the region_length in order to check for boundary46 * conditions (end-of-region). However, the region_length is a deferred47 * operation. Therefore, to complete this implementation, the generation48 * of this access width must be deferred until the region length has49 * been evaluated.50 *51 ******************************************************************************/52 53static u3254acpi_ex_generate_access(u32 field_bit_offset,55 u32 field_bit_length, u32 region_length)56{57 u32 field_byte_length;58 u32 field_byte_offset;59 u32 field_byte_end_offset;60 u32 access_byte_width;61 u32 field_start_offset;62 u32 field_end_offset;63 u32 minimum_access_width = 0xFFFFFFFF;64 u32 minimum_accesses = 0xFFFFFFFF;65 u32 accesses;66 67 ACPI_FUNCTION_TRACE(ex_generate_access);68 69 /* Round Field start offset and length to "minimal" byte boundaries */70 71 field_byte_offset = ACPI_DIV_8(ACPI_ROUND_DOWN(field_bit_offset, 8));72 73 field_byte_end_offset =74 ACPI_DIV_8(ACPI_ROUND_UP(field_bit_length + field_bit_offset, 8));75 76 field_byte_length = field_byte_end_offset - field_byte_offset;77 78 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,79 "Bit length %u, Bit offset %u\n",80 field_bit_length, field_bit_offset));81 82 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,83 "Byte Length %u, Byte Offset %u, End Offset %u\n",84 field_byte_length, field_byte_offset,85 field_byte_end_offset));86 87 /*88 * Iterative search for the maximum access width that is both aligned89 * and does not go beyond the end of the region90 *91 * Start at byte_acc and work upwards to qword_acc max. (1,2,4,8 bytes)92 */93 for (access_byte_width = 1; access_byte_width <= 8;94 access_byte_width <<= 1) {95 /*96 * 1) Round end offset up to next access boundary and make sure that97 * this does not go beyond the end of the parent region.98 * 2) When the Access width is greater than the field_byte_length, we99 * are done. (This does not optimize for the perfectly aligned100 * case yet).101 */102 if (ACPI_ROUND_UP(field_byte_end_offset, access_byte_width) <=103 region_length) {104 field_start_offset =105 ACPI_ROUND_DOWN(field_byte_offset,106 access_byte_width) /107 access_byte_width;108 109 field_end_offset =110 ACPI_ROUND_UP((field_byte_length +111 field_byte_offset),112 access_byte_width) /113 access_byte_width;114 115 accesses = field_end_offset - field_start_offset;116 117 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,118 "AccessWidth %u end is within region\n",119 access_byte_width));120 121 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,122 "Field Start %u, Field End %u -- requires %u accesses\n",123 field_start_offset, field_end_offset,124 accesses));125 126 /* Single access is optimal */127 128 if (accesses <= 1) {129 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,130 "Entire field can be accessed "131 "with one operation of size %u\n",132 access_byte_width));133 return_VALUE(access_byte_width);134 }135 136 /*137 * Fits in the region, but requires more than one read/write.138 * try the next wider access on next iteration139 */140 if (accesses < minimum_accesses) {141 minimum_accesses = accesses;142 minimum_access_width = access_byte_width;143 }144 } else {145 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,146 "AccessWidth %u end is NOT within region\n",147 access_byte_width));148 if (access_byte_width == 1) {149 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,150 "Field goes beyond end-of-region!\n"));151 152 /* Field does not fit in the region at all */153 154 return_VALUE(0);155 }156 157 /*158 * This width goes beyond the end-of-region, back off to159 * previous access160 */161 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,162 "Backing off to previous optimal access width of %u\n",163 minimum_access_width));164 return_VALUE(minimum_access_width);165 }166 }167 168 /*169 * Could not read/write field with one operation,170 * just use max access width171 */172 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,173 "Cannot access field in one operation, using width 8\n"));174 175 return_VALUE(8);176}177#endif /* ACPI_UNDER_DEVELOPMENT */178 179/*******************************************************************************180 *181 * FUNCTION: acpi_ex_decode_field_access182 *183 * PARAMETERS: obj_desc - Field object184 * field_flags - Encoded fieldflags (contains access bits)185 * return_byte_alignment - Where the byte alignment is returned186 *187 * RETURN: Field granularity (8, 16, 32 or 64) and188 * byte_alignment (1, 2, 3, or 4)189 *190 * DESCRIPTION: Decode the access_type bits of a field definition.191 *192 ******************************************************************************/193 194static u32195acpi_ex_decode_field_access(union acpi_operand_object *obj_desc,196 u8 field_flags, u32 * return_byte_alignment)197{198 u32 access;199 u32 byte_alignment;200 u32 bit_length;201 202 ACPI_FUNCTION_TRACE(ex_decode_field_access);203 204 access = (field_flags & AML_FIELD_ACCESS_TYPE_MASK);205 206 switch (access) {207 case AML_FIELD_ACCESS_ANY:208 209#ifdef ACPI_UNDER_DEVELOPMENT210 byte_alignment =211 acpi_ex_generate_access(obj_desc->common_field.212 start_field_bit_offset,213 obj_desc->common_field.bit_length,214 0xFFFFFFFF215 /* Temp until we pass region_length as parameter */216 );217 bit_length = byte_alignment * 8;218#endif219 220 byte_alignment = 1;221 bit_length = 8;222 break;223 224 case AML_FIELD_ACCESS_BYTE:225 case AML_FIELD_ACCESS_BUFFER: /* ACPI 2.0 (SMBus Buffer) */226 227 byte_alignment = 1;228 bit_length = 8;229 break;230 231 case AML_FIELD_ACCESS_WORD:232 233 byte_alignment = 2;234 bit_length = 16;235 break;236 237 case AML_FIELD_ACCESS_DWORD:238 239 byte_alignment = 4;240 bit_length = 32;241 break;242 243 case AML_FIELD_ACCESS_QWORD: /* ACPI 2.0 */244 245 byte_alignment = 8;246 bit_length = 64;247 break;248 249 default:250 251 /* Invalid field access type */252 253 ACPI_ERROR((AE_INFO, "Unknown field access type 0x%X", access));254 255 return_UINT32(0);256 }257 258 if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {259 /*260 * buffer_field access can be on any byte boundary, so the261 * byte_alignment is always 1 byte -- regardless of any byte_alignment262 * implied by the field access type.263 */264 byte_alignment = 1;265 }266 267 *return_byte_alignment = byte_alignment;268 return_UINT32(bit_length);269}270 271/*******************************************************************************272 *273 * FUNCTION: acpi_ex_prep_common_field_object274 *275 * PARAMETERS: obj_desc - The field object276 * field_flags - Access, lock_rule, and update_rule.277 * The format of a field_flag is described278 * in the ACPI specification279 * field_attribute - Special attributes (not used)280 * field_bit_position - Field start position281 * field_bit_length - Field length in number of bits282 *283 * RETURN: Status284 *285 * DESCRIPTION: Initialize the areas of the field object that are common286 * to the various types of fields. Note: This is very "sensitive"287 * code because we are solving the general case for field288 * alignment.289 *290 ******************************************************************************/291 292acpi_status293acpi_ex_prep_common_field_object(union acpi_operand_object *obj_desc,294 u8 field_flags,295 u8 field_attribute,296 u32 field_bit_position, u32 field_bit_length)297{298 u32 access_bit_width;299 u32 byte_alignment;300 u32 nearest_byte_address;301 302 ACPI_FUNCTION_TRACE(ex_prep_common_field_object);303 304 /*305 * Note: the structure being initialized is the306 * ACPI_COMMON_FIELD_INFO; No structure fields outside of the common307 * area are initialized by this procedure.308 */309 obj_desc->common_field.field_flags = field_flags;310 obj_desc->common_field.attribute = field_attribute;311 obj_desc->common_field.bit_length = field_bit_length;312 313 /*314 * Decode the access type so we can compute offsets. The access type gives315 * two pieces of information - the width of each field access and the316 * necessary byte_alignment (address granularity) of the access.317 *318 * For any_acc, the access_bit_width is the largest width that is both319 * necessary and possible in an attempt to access the whole field in one320 * I/O operation. However, for any_acc, the byte_alignment is always one321 * byte.322 *323 * For all Buffer Fields, the byte_alignment is always one byte.324 *325 * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is326 * the same (equivalent) as the byte_alignment.327 */328 access_bit_width =329 acpi_ex_decode_field_access(obj_desc, field_flags, &byte_alignment);330 if (!access_bit_width) {331 return_ACPI_STATUS(AE_AML_OPERAND_VALUE);332 }333 334 /* Setup width (access granularity) fields (values are: 1, 2, 4, 8) */335 336 obj_desc->common_field.access_byte_width = (u8)337 ACPI_DIV_8(access_bit_width);338 339 /*340 * base_byte_offset is the address of the start of the field within the341 * region. It is the byte address of the first *datum* (field-width data342 * unit) of the field. (i.e., the first datum that contains at least the343 * first *bit* of the field.)344 *345 * Note: byte_alignment is always either equal to the access_bit_width or 8346 * (Byte access), and it defines the addressing granularity of the parent347 * region or buffer.348 */349 nearest_byte_address =350 ACPI_ROUND_BITS_DOWN_TO_BYTES(field_bit_position);351 obj_desc->common_field.base_byte_offset = (u32)352 ACPI_ROUND_DOWN(nearest_byte_address, byte_alignment);353 354 /*355 * start_field_bit_offset is the offset of the first bit of the field within356 * a field datum.357 */358 obj_desc->common_field.start_field_bit_offset = (u8)359 (field_bit_position -360 ACPI_MUL_8(obj_desc->common_field.base_byte_offset));361 362 return_ACPI_STATUS(AE_OK);363}364 365/*******************************************************************************366 *367 * FUNCTION: acpi_ex_prep_field_value368 *369 * PARAMETERS: info - Contains all field creation info370 *371 * RETURN: Status372 *373 * DESCRIPTION: Construct an object of type union acpi_operand_object with a374 * subtype of def_field and connect it to the parent Node.375 *376 ******************************************************************************/377 378acpi_status acpi_ex_prep_field_value(struct acpi_create_field_info *info)379{380 union acpi_operand_object *obj_desc;381 union acpi_operand_object *second_desc = NULL;382 acpi_status status;383 u32 access_byte_width;384 u32 type;385 386 ACPI_FUNCTION_TRACE(ex_prep_field_value);387 388 /* Parameter validation */389 390 if (info->field_type != ACPI_TYPE_LOCAL_INDEX_FIELD) {391 if (!info->region_node) {392 ACPI_ERROR((AE_INFO, "Null RegionNode"));393 return_ACPI_STATUS(AE_AML_NO_OPERAND);394 }395 396 type = acpi_ns_get_type(info->region_node);397 if (type != ACPI_TYPE_REGION) {398 ACPI_ERROR((AE_INFO,399 "Needed Region, found type 0x%X (%s)", type,400 acpi_ut_get_type_name(type)));401 402 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);403 }404 }405 406 /* Allocate a new field object */407 408 obj_desc = acpi_ut_create_internal_object(info->field_type);409 if (!obj_desc) {410 return_ACPI_STATUS(AE_NO_MEMORY);411 }412 413 /* Initialize areas of the object that are common to all fields */414 415 obj_desc->common_field.node = info->field_node;416 status = acpi_ex_prep_common_field_object(obj_desc,417 info->field_flags,418 info->attribute,419 info->field_bit_position,420 info->field_bit_length);421 if (ACPI_FAILURE(status)) {422 acpi_ut_delete_object_desc(obj_desc);423 return_ACPI_STATUS(status);424 }425 426 /* Initialize areas of the object that are specific to the field type */427 428 switch (info->field_type) {429 case ACPI_TYPE_LOCAL_REGION_FIELD:430 431 obj_desc->field.region_obj =432 acpi_ns_get_attached_object(info->region_node);433 434 /* Fields specific to generic_serial_bus fields */435 436 obj_desc->field.access_length = info->access_length;437 438 if (info->connection_node) {439 second_desc = info->connection_node->object;440 if (second_desc == NULL) {441 break;442 }443 if (!(second_desc->common.flags & AOPOBJ_DATA_VALID)) {444 status =445 acpi_ds_get_buffer_arguments(second_desc);446 if (ACPI_FAILURE(status)) {447 acpi_ut_delete_object_desc(obj_desc);448 return_ACPI_STATUS(status);449 }450 }451 452 obj_desc->field.resource_buffer =453 second_desc->buffer.pointer;454 obj_desc->field.resource_length =455 (u16)second_desc->buffer.length;456 } else if (info->resource_buffer) {457 obj_desc->field.resource_buffer = info->resource_buffer;458 obj_desc->field.resource_length = info->resource_length;459 }460 461 obj_desc->field.pin_number_index = info->pin_number_index;462 463 /* Allow full data read from EC address space */464 465 if ((obj_desc->field.region_obj->region.space_id ==466 ACPI_ADR_SPACE_EC)467 && (obj_desc->common_field.bit_length > 8)) {468 access_byte_width =469 ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.470 bit_length);471 472 /* Maximum byte width supported is 255 */473 474 if (access_byte_width < 256) {475 obj_desc->common_field.access_byte_width =476 (u8)access_byte_width;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 unit510 * opcode and operands -- since the bank_value511 * 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_obj533 || !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 behavior547 *548 * The value written to the Index register is the byte offset of the549 * target field in units of the granularity of the index_field550 *551 * Previously, the value was calculated as an index in terms of the552 * 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, "569 "Gran %X, Index %p, Data %p\n",570 obj_desc->index_field.start_field_bit_offset,571 obj_desc->index_field.base_byte_offset,572 obj_desc->index_field.value,573 obj_desc->field.access_byte_width,574 obj_desc->index_field.index_obj,575 obj_desc->index_field.data_obj));576 break;577 578 default:579 580 /* No other types should get here */581 582 break;583 }584 585 /*586 * Store the constructed descriptor (obj_desc) into the parent Node,587 * preserving the current type of that named_obj.588 */589 status =590 acpi_ns_attach_object(info->field_node, obj_desc,591 acpi_ns_get_type(info->field_node));592 593 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,594 "Set NamedObj %p [%4.4s], ObjDesc %p\n",595 info->field_node,596 acpi_ut_get_node_name(info->field_node), obj_desc));597 598 /* Remove local reference to the object */599 600 acpi_ut_remove_reference(obj_desc);601 return_ACPI_STATUS(status);602}603