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v3.5.6
 
   1/******************************************************************************
   2 *
   3 * Module Name: exfldio - Aml Field I/O
   4 *
 
 
   5 *****************************************************************************/
   6
   7/*
   8 * Copyright (C) 2000 - 2012, Intel Corp.
   9 * All rights reserved.
  10 *
  11 * Redistribution and use in source and binary forms, with or without
  12 * modification, are permitted provided that the following conditions
  13 * are met:
  14 * 1. Redistributions of source code must retain the above copyright
  15 *    notice, this list of conditions, and the following disclaimer,
  16 *    without modification.
  17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18 *    substantially similar to the "NO WARRANTY" disclaimer below
  19 *    ("Disclaimer") and any redistribution must be conditioned upon
  20 *    including a substantially similar Disclaimer requirement for further
  21 *    binary redistribution.
  22 * 3. Neither the names of the above-listed copyright holders nor the names
  23 *    of any contributors may be used to endorse or promote products derived
  24 *    from this software without specific prior written permission.
  25 *
  26 * Alternatively, this software may be distributed under the terms of the
  27 * GNU General Public License ("GPL") version 2 as published by the Free
  28 * Software Foundation.
  29 *
  30 * NO WARRANTY
  31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41 * POSSIBILITY OF SUCH DAMAGES.
  42 */
  43
  44#include <acpi/acpi.h>
  45#include "accommon.h"
  46#include "acinterp.h"
  47#include "amlcode.h"
  48#include "acevents.h"
  49#include "acdispat.h"
  50
  51#define _COMPONENT          ACPI_EXECUTER
  52ACPI_MODULE_NAME("exfldio")
  53
  54/* Local prototypes */
  55static acpi_status
  56acpi_ex_field_datum_io(union acpi_operand_object *obj_desc,
  57		       u32 field_datum_byte_offset,
  58		       u64 *value, u32 read_write);
  59
  60static u8
  61acpi_ex_register_overflow(union acpi_operand_object *obj_desc, u64 value);
  62
  63static acpi_status
  64acpi_ex_setup_region(union acpi_operand_object *obj_desc,
  65		     u32 field_datum_byte_offset);
  66
  67/*******************************************************************************
  68 *
  69 * FUNCTION:    acpi_ex_setup_region
  70 *
  71 * PARAMETERS:  obj_desc                - Field to be read or written
  72 *              field_datum_byte_offset - Byte offset of this datum within the
  73 *                                        parent field
  74 *
  75 * RETURN:      Status
  76 *
  77 * DESCRIPTION: Common processing for acpi_ex_extract_from_field and
  78 *              acpi_ex_insert_into_field. Initialize the Region if necessary and
  79 *              validate the request.
  80 *
  81 ******************************************************************************/
  82
  83static acpi_status
  84acpi_ex_setup_region(union acpi_operand_object *obj_desc,
  85		     u32 field_datum_byte_offset)
  86{
  87	acpi_status status = AE_OK;
  88	union acpi_operand_object *rgn_desc;
  89	u8 space_id;
  90
  91	ACPI_FUNCTION_TRACE_U32(ex_setup_region, field_datum_byte_offset);
  92
  93	rgn_desc = obj_desc->common_field.region_obj;
  94
  95	/* We must have a valid region */
  96
  97	if (rgn_desc->common.type != ACPI_TYPE_REGION) {
  98		ACPI_ERROR((AE_INFO, "Needed Region, found type 0x%X (%s)",
  99			    rgn_desc->common.type,
 100			    acpi_ut_get_object_type_name(rgn_desc)));
 101
 102		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 103	}
 104
 105	space_id = rgn_desc->region.space_id;
 106
 107	/* Validate the Space ID */
 108
 109	if (!acpi_is_valid_space_id(space_id)) {
 110		ACPI_ERROR((AE_INFO,
 111			    "Invalid/unknown Address Space ID: 0x%2.2X",
 112			    space_id));
 113		return_ACPI_STATUS(AE_AML_INVALID_SPACE_ID);
 114	}
 115
 116	/*
 117	 * If the Region Address and Length have not been previously evaluated,
 118	 * evaluate them now and save the results.
 119	 */
 120	if (!(rgn_desc->common.flags & AOPOBJ_DATA_VALID)) {
 121		status = acpi_ds_get_region_arguments(rgn_desc);
 122		if (ACPI_FAILURE(status)) {
 123			return_ACPI_STATUS(status);
 124		}
 125	}
 126
 127	/* Exit if Address/Length have been disallowed by the host OS */
 128
 129	if (rgn_desc->common.flags & AOPOBJ_INVALID) {
 130		return_ACPI_STATUS(AE_AML_ILLEGAL_ADDRESS);
 131	}
 132
 133	/*
 134	 * Exit now for SMBus, GSBus or IPMI address space, it has a non-linear
 135	 * address space and the request cannot be directly validated
 136	 */
 137	if (space_id == ACPI_ADR_SPACE_SMBUS ||
 138	    space_id == ACPI_ADR_SPACE_GSBUS ||
 139	    space_id == ACPI_ADR_SPACE_IPMI) {
 140
 141		/* SMBus or IPMI has a non-linear address space */
 142
 143		return_ACPI_STATUS(AE_OK);
 144	}
 145#ifdef ACPI_UNDER_DEVELOPMENT
 146	/*
 147	 * If the Field access is any_acc, we can now compute the optimal
 148	 * access (because we know know the length of the parent region)
 149	 */
 150	if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
 151		if (ACPI_FAILURE(status)) {
 152			return_ACPI_STATUS(status);
 153		}
 154	}
 155#endif
 156
 157	/*
 158	 * Validate the request.  The entire request from the byte offset for a
 159	 * length of one field datum (access width) must fit within the region.
 160	 * (Region length is specified in bytes)
 161	 */
 162	if (rgn_desc->region.length <
 163	    (obj_desc->common_field.base_byte_offset + field_datum_byte_offset +
 164	     obj_desc->common_field.access_byte_width)) {
 165		if (acpi_gbl_enable_interpreter_slack) {
 166			/*
 167			 * Slack mode only:  We will go ahead and allow access to this
 168			 * field if it is within the region length rounded up to the next
 169			 * access width boundary. acpi_size cast for 64-bit compile.
 170			 */
 171			if (ACPI_ROUND_UP(rgn_desc->region.length,
 172					  obj_desc->common_field.
 173					  access_byte_width) >=
 174			    ((acpi_size) obj_desc->common_field.
 175			     base_byte_offset +
 176			     obj_desc->common_field.access_byte_width +
 177			     field_datum_byte_offset)) {
 178				return_ACPI_STATUS(AE_OK);
 179			}
 180		}
 181
 182		if (rgn_desc->region.length <
 183		    obj_desc->common_field.access_byte_width) {
 184			/*
 185			 * This is the case where the access_type (acc_word, etc.) is wider
 186			 * than the region itself.  For example, a region of length one
 187			 * byte, and a field with Dword access specified.
 188			 */
 189			ACPI_ERROR((AE_INFO,
 190				    "Field [%4.4s] access width (%u bytes) too large for region [%4.4s] (length %u)",
 
 191				    acpi_ut_get_node_name(obj_desc->
 192							  common_field.node),
 193				    obj_desc->common_field.access_byte_width,
 194				    acpi_ut_get_node_name(rgn_desc->region.
 195							  node),
 196				    rgn_desc->region.length));
 197		}
 198
 199		/*
 200		 * Offset rounded up to next multiple of field width
 201		 * exceeds region length, indicate an error
 202		 */
 203		ACPI_ERROR((AE_INFO,
 204			    "Field [%4.4s] Base+Offset+Width %u+%u+%u is beyond end of region [%4.4s] (length %u)",
 
 205			    acpi_ut_get_node_name(obj_desc->common_field.node),
 206			    obj_desc->common_field.base_byte_offset,
 207			    field_datum_byte_offset,
 208			    obj_desc->common_field.access_byte_width,
 209			    acpi_ut_get_node_name(rgn_desc->region.node),
 210			    rgn_desc->region.length));
 211
 212		return_ACPI_STATUS(AE_AML_REGION_LIMIT);
 213	}
 214
 215	return_ACPI_STATUS(AE_OK);
 216}
 217
 218/*******************************************************************************
 219 *
 220 * FUNCTION:    acpi_ex_access_region
 221 *
 222 * PARAMETERS:  obj_desc                - Field to be read
 223 *              field_datum_byte_offset - Byte offset of this datum within the
 224 *                                        parent field
 225 *              Value                   - Where to store value (must at least
 226 *                                        64 bits)
 227 *              Function                - Read or Write flag plus other region-
 228 *                                        dependent flags
 229 *
 230 * RETURN:      Status
 231 *
 232 * DESCRIPTION: Read or Write a single field datum to an Operation Region.
 233 *
 234 ******************************************************************************/
 235
 236acpi_status
 237acpi_ex_access_region(union acpi_operand_object *obj_desc,
 238		      u32 field_datum_byte_offset, u64 *value, u32 function)
 239{
 240	acpi_status status;
 241	union acpi_operand_object *rgn_desc;
 242	u32 region_offset;
 243
 244	ACPI_FUNCTION_TRACE(ex_access_region);
 245
 246	/*
 247	 * Ensure that the region operands are fully evaluated and verify
 248	 * the validity of the request
 249	 */
 250	status = acpi_ex_setup_region(obj_desc, field_datum_byte_offset);
 251	if (ACPI_FAILURE(status)) {
 252		return_ACPI_STATUS(status);
 253	}
 254
 255	/*
 256	 * The physical address of this field datum is:
 257	 *
 258	 * 1) The base of the region, plus
 259	 * 2) The base offset of the field, plus
 260	 * 3) The current offset into the field
 261	 */
 262	rgn_desc = obj_desc->common_field.region_obj;
 263	region_offset =
 264	    obj_desc->common_field.base_byte_offset + field_datum_byte_offset;
 265
 266	if ((function & ACPI_IO_MASK) == ACPI_READ) {
 267		ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, "[READ]"));
 268	} else {
 269		ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, "[WRITE]"));
 270	}
 271
 272	ACPI_DEBUG_PRINT_RAW((ACPI_DB_BFIELD,
 273			      " Region [%s:%X], Width %X, ByteBase %X, Offset %X at %p\n",
 274			      acpi_ut_get_region_name(rgn_desc->region.
 275						      space_id),
 276			      rgn_desc->region.space_id,
 277			      obj_desc->common_field.access_byte_width,
 278			      obj_desc->common_field.base_byte_offset,
 279			      field_datum_byte_offset, ACPI_CAST_PTR(void,
 280								     (rgn_desc->
 281								      region.
 282								      address +
 283								      region_offset))));
 284
 285	/* Invoke the appropriate address_space/op_region handler */
 286
 287	status = acpi_ev_address_space_dispatch(rgn_desc, obj_desc,
 288						function, region_offset,
 289						ACPI_MUL_8(obj_desc->
 290							   common_field.
 291							   access_byte_width),
 292						value);
 293
 294	if (ACPI_FAILURE(status)) {
 295		if (status == AE_NOT_IMPLEMENTED) {
 296			ACPI_ERROR((AE_INFO,
 297				    "Region %s (ID=%u) not implemented",
 298				    acpi_ut_get_region_name(rgn_desc->region.
 299							    space_id),
 300				    rgn_desc->region.space_id));
 301		} else if (status == AE_NOT_EXIST) {
 302			ACPI_ERROR((AE_INFO,
 303				    "Region %s (ID=%u) has no handler",
 304				    acpi_ut_get_region_name(rgn_desc->region.
 305							    space_id),
 306				    rgn_desc->region.space_id));
 307		}
 308	}
 309
 310	return_ACPI_STATUS(status);
 311}
 312
 313/*******************************************************************************
 314 *
 315 * FUNCTION:    acpi_ex_register_overflow
 316 *
 317 * PARAMETERS:  obj_desc                - Register(Field) to be written
 318 *              Value                   - Value to be stored
 319 *
 320 * RETURN:      TRUE if value overflows the field, FALSE otherwise
 321 *
 322 * DESCRIPTION: Check if a value is out of range of the field being written.
 323 *              Used to check if the values written to Index and Bank registers
 324 *              are out of range.  Normally, the value is simply truncated
 325 *              to fit the field, but this case is most likely a serious
 326 *              coding error in the ASL.
 327 *
 328 ******************************************************************************/
 329
 330static u8
 331acpi_ex_register_overflow(union acpi_operand_object *obj_desc, u64 value)
 332{
 333	ACPI_FUNCTION_NAME(ex_register_overflow);
 334
 335	if (obj_desc->common_field.bit_length >= ACPI_INTEGER_BIT_SIZE) {
 336		/*
 337		 * The field is large enough to hold the maximum integer, so we can
 338		 * never overflow it.
 339		 */
 340		return (FALSE);
 341	}
 342
 343	if (value >= ((u64) 1 << obj_desc->common_field.bit_length)) {
 344		/*
 345		 * The Value is larger than the maximum value that can fit into
 346		 * the register.
 347		 */
 348		ACPI_ERROR((AE_INFO,
 349			    "Index value 0x%8.8X%8.8X overflows field width 0x%X",
 350			    ACPI_FORMAT_UINT64(value),
 351			    obj_desc->common_field.bit_length));
 352
 353		return (TRUE);
 354	}
 355
 356	/* The Value will fit into the field with no truncation */
 357
 358	return (FALSE);
 359}
 360
 361/*******************************************************************************
 362 *
 363 * FUNCTION:    acpi_ex_field_datum_io
 364 *
 365 * PARAMETERS:  obj_desc                - Field to be read
 366 *              field_datum_byte_offset - Byte offset of this datum within the
 367 *                                        parent field
 368 *              Value                   - Where to store value (must be 64 bits)
 369 *              read_write              - Read or Write flag
 370 *
 371 * RETURN:      Status
 372 *
 373 * DESCRIPTION: Read or Write a single datum of a field.  The field_type is
 374 *              demultiplexed here to handle the different types of fields
 375 *              (buffer_field, region_field, index_field, bank_field)
 376 *
 377 ******************************************************************************/
 378
 379static acpi_status
 380acpi_ex_field_datum_io(union acpi_operand_object *obj_desc,
 381		       u32 field_datum_byte_offset, u64 *value, u32 read_write)
 382{
 383	acpi_status status;
 384	u64 local_value;
 385
 386	ACPI_FUNCTION_TRACE_U32(ex_field_datum_io, field_datum_byte_offset);
 387
 388	if (read_write == ACPI_READ) {
 389		if (!value) {
 390			local_value = 0;
 391
 392			/* To support reads without saving return value */
 393			value = &local_value;
 394		}
 395
 396		/* Clear the entire return buffer first, [Very Important!] */
 397
 398		*value = 0;
 399	}
 400
 401	/*
 402	 * The four types of fields are:
 403	 *
 404	 * buffer_field - Read/write from/to a Buffer
 405	 * region_field - Read/write from/to a Operation Region.
 406	 * bank_field  - Write to a Bank Register, then read/write from/to an
 407	 *               operation_region
 408	 * index_field - Write to an Index Register, then read/write from/to a
 409	 *               Data Register
 410	 */
 411	switch (obj_desc->common.type) {
 412	case ACPI_TYPE_BUFFER_FIELD:
 413		/*
 414		 * If the buffer_field arguments have not been previously evaluated,
 415		 * evaluate them now and save the results.
 416		 */
 417		if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
 418			status = acpi_ds_get_buffer_field_arguments(obj_desc);
 419			if (ACPI_FAILURE(status)) {
 420				return_ACPI_STATUS(status);
 421			}
 422		}
 423
 424		if (read_write == ACPI_READ) {
 425			/*
 426			 * Copy the data from the source buffer.
 427			 * Length is the field width in bytes.
 428			 */
 429			ACPI_MEMCPY(value,
 430				    (obj_desc->buffer_field.buffer_obj)->buffer.
 431				    pointer +
 432				    obj_desc->buffer_field.base_byte_offset +
 433				    field_datum_byte_offset,
 434				    obj_desc->common_field.access_byte_width);
 435		} else {
 436			/*
 437			 * Copy the data to the target buffer.
 438			 * Length is the field width in bytes.
 439			 */
 440			ACPI_MEMCPY((obj_desc->buffer_field.buffer_obj)->buffer.
 441				    pointer +
 442				    obj_desc->buffer_field.base_byte_offset +
 443				    field_datum_byte_offset, value,
 444				    obj_desc->common_field.access_byte_width);
 445		}
 446
 447		status = AE_OK;
 448		break;
 449
 450	case ACPI_TYPE_LOCAL_BANK_FIELD:
 451
 452		/*
 453		 * Ensure that the bank_value is not beyond the capacity of
 454		 * the register
 455		 */
 456		if (acpi_ex_register_overflow(obj_desc->bank_field.bank_obj,
 457					      (u64) obj_desc->bank_field.
 458					      value)) {
 459			return_ACPI_STATUS(AE_AML_REGISTER_LIMIT);
 460		}
 461
 462		/*
 463		 * For bank_fields, we must write the bank_value to the bank_register
 464		 * (itself a region_field) before we can access the data.
 465		 */
 466		status =
 467		    acpi_ex_insert_into_field(obj_desc->bank_field.bank_obj,
 468					      &obj_desc->bank_field.value,
 469					      sizeof(obj_desc->bank_field.
 470						     value));
 471		if (ACPI_FAILURE(status)) {
 472			return_ACPI_STATUS(status);
 473		}
 474
 475		/*
 476		 * Now that the Bank has been selected, fall through to the
 477		 * region_field case and write the datum to the Operation Region
 478		 */
 479
 480		/*lint -fallthrough */
 481
 482	case ACPI_TYPE_LOCAL_REGION_FIELD:
 483		/*
 484		 * For simple region_fields, we just directly access the owning
 485		 * Operation Region.
 486		 */
 487		status =
 488		    acpi_ex_access_region(obj_desc, field_datum_byte_offset,
 489					  value, read_write);
 490		break;
 491
 492	case ACPI_TYPE_LOCAL_INDEX_FIELD:
 493
 494		/*
 495		 * Ensure that the index_value is not beyond the capacity of
 496		 * the register
 497		 */
 498		if (acpi_ex_register_overflow(obj_desc->index_field.index_obj,
 499					      (u64) obj_desc->index_field.
 500					      value)) {
 501			return_ACPI_STATUS(AE_AML_REGISTER_LIMIT);
 502		}
 503
 504		/* Write the index value to the index_register (itself a region_field) */
 505
 506		field_datum_byte_offset += obj_desc->index_field.value;
 507
 508		ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 509				  "Write to Index Register: Value %8.8X\n",
 510				  field_datum_byte_offset));
 511
 512		status =
 513		    acpi_ex_insert_into_field(obj_desc->index_field.index_obj,
 514					      &field_datum_byte_offset,
 515					      sizeof(field_datum_byte_offset));
 516		if (ACPI_FAILURE(status)) {
 517			return_ACPI_STATUS(status);
 518		}
 519
 520		if (read_write == ACPI_READ) {
 521
 522			/* Read the datum from the data_register */
 523
 524			ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 525					  "Read from Data Register\n"));
 526
 527			status =
 528			    acpi_ex_extract_from_field(obj_desc->index_field.
 529						       data_obj, value,
 530						       sizeof(u64));
 531		} else {
 532			/* Write the datum to the data_register */
 533
 534			ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 535					  "Write to Data Register: Value %8.8X%8.8X\n",
 536					  ACPI_FORMAT_UINT64(*value)));
 537
 538			status =
 539			    acpi_ex_insert_into_field(obj_desc->index_field.
 540						      data_obj, value,
 541						      sizeof(u64));
 542		}
 543		break;
 544
 545	default:
 546
 547		ACPI_ERROR((AE_INFO, "Wrong object type in field I/O %u",
 548			    obj_desc->common.type));
 549		status = AE_AML_INTERNAL;
 550		break;
 551	}
 552
 553	if (ACPI_SUCCESS(status)) {
 554		if (read_write == ACPI_READ) {
 555			ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 556					  "Value Read %8.8X%8.8X, Width %u\n",
 557					  ACPI_FORMAT_UINT64(*value),
 558					  obj_desc->common_field.
 559					  access_byte_width));
 560		} else {
 561			ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 562					  "Value Written %8.8X%8.8X, Width %u\n",
 563					  ACPI_FORMAT_UINT64(*value),
 564					  obj_desc->common_field.
 565					  access_byte_width));
 566		}
 567	}
 568
 569	return_ACPI_STATUS(status);
 570}
 571
 572/*******************************************************************************
 573 *
 574 * FUNCTION:    acpi_ex_write_with_update_rule
 575 *
 576 * PARAMETERS:  obj_desc                - Field to be written
 577 *              Mask                    - bitmask within field datum
 578 *              field_value             - Value to write
 579 *              field_datum_byte_offset - Offset of datum within field
 580 *
 581 * RETURN:      Status
 582 *
 583 * DESCRIPTION: Apply the field update rule to a field write
 584 *
 585 ******************************************************************************/
 586
 587acpi_status
 588acpi_ex_write_with_update_rule(union acpi_operand_object *obj_desc,
 589			       u64 mask,
 590			       u64 field_value, u32 field_datum_byte_offset)
 591{
 592	acpi_status status = AE_OK;
 593	u64 merged_value;
 594	u64 current_value;
 595
 596	ACPI_FUNCTION_TRACE_U32(ex_write_with_update_rule, mask);
 597
 598	/* Start with the new bits  */
 599
 600	merged_value = field_value;
 601
 602	/* If the mask is all ones, we don't need to worry about the update rule */
 603
 604	if (mask != ACPI_UINT64_MAX) {
 605
 606		/* Decode the update rule */
 607
 608		switch (obj_desc->common_field.
 609			field_flags & AML_FIELD_UPDATE_RULE_MASK) {
 610		case AML_FIELD_UPDATE_PRESERVE:
 611			/*
 612			 * Check if update rule needs to be applied (not if mask is all
 613			 * ones)  The left shift drops the bits we want to ignore.
 614			 */
 615			if ((~mask << (ACPI_MUL_8(sizeof(mask)) -
 616				       ACPI_MUL_8(obj_desc->common_field.
 617						  access_byte_width))) != 0) {
 618				/*
 619				 * Read the current contents of the byte/word/dword containing
 620				 * the field, and merge with the new field value.
 621				 */
 622				status =
 623				    acpi_ex_field_datum_io(obj_desc,
 624							   field_datum_byte_offset,
 625							   &current_value,
 626							   ACPI_READ);
 627				if (ACPI_FAILURE(status)) {
 628					return_ACPI_STATUS(status);
 629				}
 630
 631				merged_value |= (current_value & ~mask);
 632			}
 633			break;
 634
 635		case AML_FIELD_UPDATE_WRITE_AS_ONES:
 636
 637			/* Set positions outside the field to all ones */
 638
 639			merged_value |= ~mask;
 640			break;
 641
 642		case AML_FIELD_UPDATE_WRITE_AS_ZEROS:
 643
 644			/* Set positions outside the field to all zeros */
 645
 646			merged_value &= mask;
 647			break;
 648
 649		default:
 650
 651			ACPI_ERROR((AE_INFO,
 652				    "Unknown UpdateRule value: 0x%X",
 653				    (obj_desc->common_field.
 654				     field_flags &
 655				     AML_FIELD_UPDATE_RULE_MASK)));
 656			return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
 657		}
 658	}
 659
 660	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
 661			  "Mask %8.8X%8.8X, DatumOffset %X, Width %X, Value %8.8X%8.8X, MergedValue %8.8X%8.8X\n",
 
 662			  ACPI_FORMAT_UINT64(mask),
 663			  field_datum_byte_offset,
 664			  obj_desc->common_field.access_byte_width,
 665			  ACPI_FORMAT_UINT64(field_value),
 666			  ACPI_FORMAT_UINT64(merged_value)));
 667
 668	/* Write the merged value */
 669
 670	status = acpi_ex_field_datum_io(obj_desc, field_datum_byte_offset,
 671					&merged_value, ACPI_WRITE);
 
 672
 673	return_ACPI_STATUS(status);
 674}
 675
 676/*******************************************************************************
 677 *
 678 * FUNCTION:    acpi_ex_extract_from_field
 679 *
 680 * PARAMETERS:  obj_desc            - Field to be read
 681 *              Buffer              - Where to store the field data
 682 *              buffer_length       - Length of Buffer
 683 *
 684 * RETURN:      Status
 685 *
 686 * DESCRIPTION: Retrieve the current value of the given field
 687 *
 688 ******************************************************************************/
 689
 690acpi_status
 691acpi_ex_extract_from_field(union acpi_operand_object *obj_desc,
 692			   void *buffer, u32 buffer_length)
 693{
 694	acpi_status status;
 695	u64 raw_datum;
 696	u64 merged_datum;
 697	u32 field_offset = 0;
 698	u32 buffer_offset = 0;
 699	u32 buffer_tail_bits;
 700	u32 datum_count;
 701	u32 field_datum_count;
 702	u32 access_bit_width;
 703	u32 i;
 704
 705	ACPI_FUNCTION_TRACE(ex_extract_from_field);
 706
 707	/* Validate target buffer and clear it */
 708
 709	if (buffer_length <
 710	    ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.bit_length)) {
 711		ACPI_ERROR((AE_INFO,
 712			    "Field size %u (bits) is too large for buffer (%u)",
 713			    obj_desc->common_field.bit_length, buffer_length));
 714
 715		return_ACPI_STATUS(AE_BUFFER_OVERFLOW);
 716	}
 717
 718	ACPI_MEMSET(buffer, 0, buffer_length);
 719	access_bit_width = ACPI_MUL_8(obj_desc->common_field.access_byte_width);
 720
 721	/* Handle the simple case here */
 722
 723	if ((obj_desc->common_field.start_field_bit_offset == 0) &&
 724	    (obj_desc->common_field.bit_length == access_bit_width)) {
 725		status = acpi_ex_field_datum_io(obj_desc, 0, buffer, ACPI_READ);
 
 
 
 
 
 
 
 
 
 
 
 
 726		return_ACPI_STATUS(status);
 727	}
 728
 729/* TBD: Move to common setup code */
 730
 731	/* Field algorithm is limited to sizeof(u64), truncate if needed */
 732
 733	if (obj_desc->common_field.access_byte_width > sizeof(u64)) {
 734		obj_desc->common_field.access_byte_width = sizeof(u64);
 735		access_bit_width = sizeof(u64) * 8;
 736	}
 737
 738	/* Compute the number of datums (access width data items) */
 739
 740	datum_count =
 741	    ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length,
 742			     access_bit_width);
 743
 744	field_datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length +
 745					     obj_desc->common_field.
 746					     start_field_bit_offset,
 747					     access_bit_width);
 748
 749	/* Priming read from the field */
 750
 751	status =
 752	    acpi_ex_field_datum_io(obj_desc, field_offset, &raw_datum,
 753				   ACPI_READ);
 754	if (ACPI_FAILURE(status)) {
 755		return_ACPI_STATUS(status);
 756	}
 757	merged_datum =
 758	    raw_datum >> obj_desc->common_field.start_field_bit_offset;
 759
 760	/* Read the rest of the field */
 761
 762	for (i = 1; i < field_datum_count; i++) {
 763
 764		/* Get next input datum from the field */
 765
 766		field_offset += obj_desc->common_field.access_byte_width;
 767		status = acpi_ex_field_datum_io(obj_desc, field_offset,
 768						&raw_datum, ACPI_READ);
 
 769		if (ACPI_FAILURE(status)) {
 770			return_ACPI_STATUS(status);
 771		}
 772
 773		/*
 774		 * Merge with previous datum if necessary.
 775		 *
 776		 * Note: Before the shift, check if the shift value will be larger than
 777		 * the integer size. If so, there is no need to perform the operation.
 778		 * This avoids the differences in behavior between different compilers
 779		 * concerning shift values larger than the target data width.
 780		 */
 781		if (access_bit_width -
 782		    obj_desc->common_field.start_field_bit_offset <
 783		    ACPI_INTEGER_BIT_SIZE) {
 784			merged_datum |=
 785			    raw_datum << (access_bit_width -
 786					  obj_desc->common_field.
 787					  start_field_bit_offset);
 788		}
 789
 790		if (i == datum_count) {
 791			break;
 792		}
 793
 794		/* Write merged datum to target buffer */
 795
 796		ACPI_MEMCPY(((char *)buffer) + buffer_offset, &merged_datum,
 797			    ACPI_MIN(obj_desc->common_field.access_byte_width,
 798				     buffer_length - buffer_offset));
 799
 800		buffer_offset += obj_desc->common_field.access_byte_width;
 801		merged_datum =
 802		    raw_datum >> obj_desc->common_field.start_field_bit_offset;
 803	}
 804
 805	/* Mask off any extra bits in the last datum */
 806
 807	buffer_tail_bits = obj_desc->common_field.bit_length % access_bit_width;
 808	if (buffer_tail_bits) {
 809		merged_datum &= ACPI_MASK_BITS_ABOVE(buffer_tail_bits);
 810	}
 811
 812	/* Write the last datum to the buffer */
 813
 814	ACPI_MEMCPY(((char *)buffer) + buffer_offset, &merged_datum,
 815		    ACPI_MIN(obj_desc->common_field.access_byte_width,
 816			     buffer_length - buffer_offset));
 817
 818	return_ACPI_STATUS(AE_OK);
 819}
 820
 821/*******************************************************************************
 822 *
 823 * FUNCTION:    acpi_ex_insert_into_field
 824 *
 825 * PARAMETERS:  obj_desc            - Field to be written
 826 *              Buffer              - Data to be written
 827 *              buffer_length       - Length of Buffer
 828 *
 829 * RETURN:      Status
 830 *
 831 * DESCRIPTION: Store the Buffer contents into the given field
 832 *
 833 ******************************************************************************/
 834
 835acpi_status
 836acpi_ex_insert_into_field(union acpi_operand_object *obj_desc,
 837			  void *buffer, u32 buffer_length)
 838{
 839	void *new_buffer;
 840	acpi_status status;
 841	u64 mask;
 842	u64 width_mask;
 843	u64 merged_datum;
 844	u64 raw_datum = 0;
 845	u32 field_offset = 0;
 846	u32 buffer_offset = 0;
 847	u32 buffer_tail_bits;
 848	u32 datum_count;
 849	u32 field_datum_count;
 850	u32 access_bit_width;
 851	u32 required_length;
 852	u32 i;
 853
 854	ACPI_FUNCTION_TRACE(ex_insert_into_field);
 855
 856	/* Validate input buffer */
 857
 858	new_buffer = NULL;
 859	required_length =
 860	    ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.bit_length);
 
 861	/*
 862	 * We must have a buffer that is at least as long as the field
 863	 * we are writing to.  This is because individual fields are
 864	 * indivisible and partial writes are not supported -- as per
 865	 * the ACPI specification.
 866	 */
 867	if (buffer_length < required_length) {
 868
 869		/* We need to create a new buffer */
 870
 871		new_buffer = ACPI_ALLOCATE_ZEROED(required_length);
 872		if (!new_buffer) {
 873			return_ACPI_STATUS(AE_NO_MEMORY);
 874		}
 875
 876		/*
 877		 * Copy the original data to the new buffer, starting
 878		 * at Byte zero.  All unused (upper) bytes of the
 879		 * buffer will be 0.
 880		 */
 881		ACPI_MEMCPY((char *)new_buffer, (char *)buffer, buffer_length);
 882		buffer = new_buffer;
 883		buffer_length = required_length;
 884	}
 885
 886/* TBD: Move to common setup code */
 887
 888	/* Algo is limited to sizeof(u64), so cut the access_byte_width */
 889	if (obj_desc->common_field.access_byte_width > sizeof(u64)) {
 890		obj_desc->common_field.access_byte_width = sizeof(u64);
 891	}
 892
 893	access_bit_width = ACPI_MUL_8(obj_desc->common_field.access_byte_width);
 894
 895	/*
 896	 * Create the bitmasks used for bit insertion.
 897	 * Note: This if/else is used to bypass compiler differences with the
 898	 * shift operator
 899	 */
 900	if (access_bit_width == ACPI_INTEGER_BIT_SIZE) {
 901		width_mask = ACPI_UINT64_MAX;
 902	} else {
 903		width_mask = ACPI_MASK_BITS_ABOVE(access_bit_width);
 904	}
 905
 
 906	mask = width_mask &
 907	    ACPI_MASK_BITS_BELOW(obj_desc->common_field.start_field_bit_offset);
 908
 909	/* Compute the number of datums (access width data items) */
 910
 911	datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length,
 912				       access_bit_width);
 913
 914	field_datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length +
 915					     obj_desc->common_field.
 916					     start_field_bit_offset,
 917					     access_bit_width);
 918
 919	/* Get initial Datum from the input buffer */
 920
 921	ACPI_MEMCPY(&raw_datum, buffer,
 922		    ACPI_MIN(obj_desc->common_field.access_byte_width,
 923			     buffer_length - buffer_offset));
 924
 925	merged_datum =
 926	    raw_datum << obj_desc->common_field.start_field_bit_offset;
 927
 928	/* Write the entire field */
 929
 930	for (i = 1; i < field_datum_count; i++) {
 931
 932		/* Write merged datum to the target field */
 933
 934		merged_datum &= mask;
 935		status = acpi_ex_write_with_update_rule(obj_desc, mask,
 936							merged_datum,
 937							field_offset);
 938		if (ACPI_FAILURE(status)) {
 939			goto exit;
 940		}
 941
 942		field_offset += obj_desc->common_field.access_byte_width;
 943
 944		/*
 945		 * Start new output datum by merging with previous input datum
 946		 * if necessary.
 947		 *
 948		 * Note: Before the shift, check if the shift value will be larger than
 949		 * the integer size. If so, there is no need to perform the operation.
 950		 * This avoids the differences in behavior between different compilers
 951		 * concerning shift values larger than the target data width.
 952		 */
 953		if ((access_bit_width -
 954		     obj_desc->common_field.start_field_bit_offset) <
 955		    ACPI_INTEGER_BIT_SIZE) {
 956			merged_datum =
 957			    raw_datum >> (access_bit_width -
 958					  obj_desc->common_field.
 959					  start_field_bit_offset);
 960		} else {
 961			merged_datum = 0;
 962		}
 963
 964		mask = width_mask;
 965
 966		if (i == datum_count) {
 967			break;
 968		}
 969
 970		/* Get the next input datum from the buffer */
 971
 972		buffer_offset += obj_desc->common_field.access_byte_width;
 973		ACPI_MEMCPY(&raw_datum, ((char *)buffer) + buffer_offset,
 974			    ACPI_MIN(obj_desc->common_field.access_byte_width,
 975				     buffer_length - buffer_offset));
 976
 977		merged_datum |=
 978		    raw_datum << obj_desc->common_field.start_field_bit_offset;
 979	}
 980
 981	/* Mask off any extra bits in the last datum */
 982
 983	buffer_tail_bits = (obj_desc->common_field.bit_length +
 984			    obj_desc->common_field.start_field_bit_offset) %
 985	    access_bit_width;
 986	if (buffer_tail_bits) {
 987		mask &= ACPI_MASK_BITS_ABOVE(buffer_tail_bits);
 988	}
 989
 990	/* Write the last datum to the field */
 991
 992	merged_datum &= mask;
 993	status = acpi_ex_write_with_update_rule(obj_desc,
 994						mask, merged_datum,
 995						field_offset);
 996
 997      exit:
 998	/* Free temporary buffer if we used one */
 999
1000	if (new_buffer) {
1001		ACPI_FREE(new_buffer);
1002	}
1003	return_ACPI_STATUS(status);
1004}
v6.9.4
  1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
  2/******************************************************************************
  3 *
  4 * Module Name: exfldio - Aml Field I/O
  5 *
  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 "acevents.h"
 15#include "acdispat.h"
 16
 17#define _COMPONENT          ACPI_EXECUTER
 18ACPI_MODULE_NAME("exfldio")
 19
 20/* Local prototypes */
 21static acpi_status
 22acpi_ex_field_datum_io(union acpi_operand_object *obj_desc,
 23		       u32 field_datum_byte_offset, u64 *value, u32 read_write);
 
 24
 25static u8
 26acpi_ex_register_overflow(union acpi_operand_object *obj_desc, u64 value);
 27
 28static acpi_status
 29acpi_ex_setup_region(union acpi_operand_object *obj_desc,
 30		     u32 field_datum_byte_offset);
 31
 32/*******************************************************************************
 33 *
 34 * FUNCTION:    acpi_ex_setup_region
 35 *
 36 * PARAMETERS:  obj_desc                - Field to be read or written
 37 *              field_datum_byte_offset - Byte offset of this datum within the
 38 *                                        parent field
 39 *
 40 * RETURN:      Status
 41 *
 42 * DESCRIPTION: Common processing for acpi_ex_extract_from_field and
 43 *              acpi_ex_insert_into_field. Initialize the Region if necessary and
 44 *              validate the request.
 45 *
 46 ******************************************************************************/
 47
 48static acpi_status
 49acpi_ex_setup_region(union acpi_operand_object *obj_desc,
 50		     u32 field_datum_byte_offset)
 51{
 52	acpi_status status = AE_OK;
 53	union acpi_operand_object *rgn_desc;
 54	u8 space_id;
 55
 56	ACPI_FUNCTION_TRACE_U32(ex_setup_region, field_datum_byte_offset);
 57
 58	rgn_desc = obj_desc->common_field.region_obj;
 59
 60	/* We must have a valid region */
 61
 62	if (rgn_desc->common.type != ACPI_TYPE_REGION) {
 63		ACPI_ERROR((AE_INFO, "Needed Region, found type 0x%X (%s)",
 64			    rgn_desc->common.type,
 65			    acpi_ut_get_object_type_name(rgn_desc)));
 66
 67		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
 68	}
 69
 70	space_id = rgn_desc->region.space_id;
 71
 72	/* Validate the Space ID */
 73
 74	if (!acpi_is_valid_space_id(space_id)) {
 75		ACPI_ERROR((AE_INFO,
 76			    "Invalid/unknown Address Space ID: 0x%2.2X",
 77			    space_id));
 78		return_ACPI_STATUS(AE_AML_INVALID_SPACE_ID);
 79	}
 80
 81	/*
 82	 * If the Region Address and Length have not been previously evaluated,
 83	 * evaluate them now and save the results.
 84	 */
 85	if (!(rgn_desc->common.flags & AOPOBJ_DATA_VALID)) {
 86		status = acpi_ds_get_region_arguments(rgn_desc);
 87		if (ACPI_FAILURE(status)) {
 88			return_ACPI_STATUS(status);
 89		}
 90	}
 91
 
 
 
 
 
 
 92	/*
 93	 * Exit now for SMBus, GSBus or IPMI address space, it has a non-linear
 94	 * address space and the request cannot be directly validated
 95	 */
 96	if (space_id == ACPI_ADR_SPACE_SMBUS ||
 97	    space_id == ACPI_ADR_SPACE_GSBUS ||
 98	    space_id == ACPI_ADR_SPACE_IPMI) {
 99
100		/* SMBus or IPMI has a non-linear address space */
101
102		return_ACPI_STATUS(AE_OK);
103	}
104#ifdef ACPI_UNDER_DEVELOPMENT
105	/*
106	 * If the Field access is any_acc, we can now compute the optimal
107	 * access (because we know the length of the parent region)
108	 */
109	if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
110		if (ACPI_FAILURE(status)) {
111			return_ACPI_STATUS(status);
112		}
113	}
114#endif
115
116	/*
117	 * Validate the request. The entire request from the byte offset for a
118	 * length of one field datum (access width) must fit within the region.
119	 * (Region length is specified in bytes)
120	 */
121	if (rgn_desc->region.length <
122	    (obj_desc->common_field.base_byte_offset + field_datum_byte_offset +
123	     obj_desc->common_field.access_byte_width)) {
124		if (acpi_gbl_enable_interpreter_slack) {
125			/*
126			 * Slack mode only:  We will go ahead and allow access to this
127			 * field if it is within the region length rounded up to the next
128			 * access width boundary. acpi_size cast for 64-bit compile.
129			 */
130			if (ACPI_ROUND_UP(rgn_desc->region.length,
131					  obj_desc->common_field.
132					  access_byte_width) >=
133			    ((acpi_size)obj_desc->common_field.
134			     base_byte_offset +
135			     obj_desc->common_field.access_byte_width +
136			     field_datum_byte_offset)) {
137				return_ACPI_STATUS(AE_OK);
138			}
139		}
140
141		if (rgn_desc->region.length <
142		    obj_desc->common_field.access_byte_width) {
143			/*
144			 * This is the case where the access_type (acc_word, etc.) is wider
145			 * than the region itself. For example, a region of length one
146			 * byte, and a field with Dword access specified.
147			 */
148			ACPI_ERROR((AE_INFO,
149				    "Field [%4.4s] access width (%u bytes) "
150				    "too large for region [%4.4s] (length %u)",
151				    acpi_ut_get_node_name(obj_desc->
152							  common_field.node),
153				    obj_desc->common_field.access_byte_width,
154				    acpi_ut_get_node_name(rgn_desc->region.
155							  node),
156				    rgn_desc->region.length));
157		}
158
159		/*
160		 * Offset rounded up to next multiple of field width
161		 * exceeds region length, indicate an error
162		 */
163		ACPI_ERROR((AE_INFO,
164			    "Field [%4.4s] Base+Offset+Width %u+%u+%u "
165			    "is beyond end of region [%4.4s] (length %u)",
166			    acpi_ut_get_node_name(obj_desc->common_field.node),
167			    obj_desc->common_field.base_byte_offset,
168			    field_datum_byte_offset,
169			    obj_desc->common_field.access_byte_width,
170			    acpi_ut_get_node_name(rgn_desc->region.node),
171			    rgn_desc->region.length));
172
173		return_ACPI_STATUS(AE_AML_REGION_LIMIT);
174	}
175
176	return_ACPI_STATUS(AE_OK);
177}
178
179/*******************************************************************************
180 *
181 * FUNCTION:    acpi_ex_access_region
182 *
183 * PARAMETERS:  obj_desc                - Field to be read
184 *              field_datum_byte_offset - Byte offset of this datum within the
185 *                                        parent field
186 *              value                   - Where to store value (must at least
187 *                                        64 bits)
188 *              function                - Read or Write flag plus other region-
189 *                                        dependent flags
190 *
191 * RETURN:      Status
192 *
193 * DESCRIPTION: Read or Write a single field datum to an Operation Region.
194 *
195 ******************************************************************************/
196
197acpi_status
198acpi_ex_access_region(union acpi_operand_object *obj_desc,
199		      u32 field_datum_byte_offset, u64 *value, u32 function)
200{
201	acpi_status status;
202	union acpi_operand_object *rgn_desc;
203	u32 region_offset;
204
205	ACPI_FUNCTION_TRACE(ex_access_region);
206
207	/*
208	 * Ensure that the region operands are fully evaluated and verify
209	 * the validity of the request
210	 */
211	status = acpi_ex_setup_region(obj_desc, field_datum_byte_offset);
212	if (ACPI_FAILURE(status)) {
213		return_ACPI_STATUS(status);
214	}
215
216	/*
217	 * The physical address of this field datum is:
218	 *
219	 * 1) The base of the region, plus
220	 * 2) The base offset of the field, plus
221	 * 3) The current offset into the field
222	 */
223	rgn_desc = obj_desc->common_field.region_obj;
224	region_offset =
225	    obj_desc->common_field.base_byte_offset + field_datum_byte_offset;
226
227	if ((function & ACPI_IO_MASK) == ACPI_READ) {
228		ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, "[READ]"));
229	} else {
230		ACPI_DEBUG_PRINT((ACPI_DB_BFIELD, "[WRITE]"));
231	}
232
233	ACPI_DEBUG_PRINT_RAW((ACPI_DB_BFIELD,
234			      " Region [%s:%X], Width %X, ByteBase %X, Offset %X at %8.8X%8.8X\n",
235			      acpi_ut_get_region_name(rgn_desc->region.
236						      space_id),
237			      rgn_desc->region.space_id,
238			      obj_desc->common_field.access_byte_width,
239			      obj_desc->common_field.base_byte_offset,
240			      field_datum_byte_offset,
241			      ACPI_FORMAT_UINT64(rgn_desc->region.address +
242						 region_offset)));
 
 
243
244	/* Invoke the appropriate address_space/op_region handler */
245
246	status = acpi_ev_address_space_dispatch(rgn_desc, obj_desc,
247						function, region_offset,
248						ACPI_MUL_8(obj_desc->
249							   common_field.
250							   access_byte_width),
251						value);
252
253	if (ACPI_FAILURE(status)) {
254		if (status == AE_NOT_IMPLEMENTED) {
255			ACPI_ERROR((AE_INFO,
256				    "Region %s (ID=%u) not implemented",
257				    acpi_ut_get_region_name(rgn_desc->region.
258							    space_id),
259				    rgn_desc->region.space_id));
260		} else if (status == AE_NOT_EXIST) {
261			ACPI_ERROR((AE_INFO,
262				    "Region %s (ID=%u) has no handler",
263				    acpi_ut_get_region_name(rgn_desc->region.
264							    space_id),
265				    rgn_desc->region.space_id));
266		}
267	}
268
269	return_ACPI_STATUS(status);
270}
271
272/*******************************************************************************
273 *
274 * FUNCTION:    acpi_ex_register_overflow
275 *
276 * PARAMETERS:  obj_desc                - Register(Field) to be written
277 *              value                   - Value to be stored
278 *
279 * RETURN:      TRUE if value overflows the field, FALSE otherwise
280 *
281 * DESCRIPTION: Check if a value is out of range of the field being written.
282 *              Used to check if the values written to Index and Bank registers
283 *              are out of range. Normally, the value is simply truncated
284 *              to fit the field, but this case is most likely a serious
285 *              coding error in the ASL.
286 *
287 ******************************************************************************/
288
289static u8
290acpi_ex_register_overflow(union acpi_operand_object *obj_desc, u64 value)
291{
 
292
293	if (obj_desc->common_field.bit_length >= ACPI_INTEGER_BIT_SIZE) {
294		/*
295		 * The field is large enough to hold the maximum integer, so we can
296		 * never overflow it.
297		 */
298		return (FALSE);
299	}
300
301	if (value >= ((u64) 1 << obj_desc->common_field.bit_length)) {
302		/*
303		 * The Value is larger than the maximum value that can fit into
304		 * the register.
305		 */
306		ACPI_ERROR((AE_INFO,
307			    "Index value 0x%8.8X%8.8X overflows field width 0x%X",
308			    ACPI_FORMAT_UINT64(value),
309			    obj_desc->common_field.bit_length));
310
311		return (TRUE);
312	}
313
314	/* The Value will fit into the field with no truncation */
315
316	return (FALSE);
317}
318
319/*******************************************************************************
320 *
321 * FUNCTION:    acpi_ex_field_datum_io
322 *
323 * PARAMETERS:  obj_desc                - Field to be read
324 *              field_datum_byte_offset - Byte offset of this datum within the
325 *                                        parent field
326 *              value                   - Where to store value (must be 64 bits)
327 *              read_write              - Read or Write flag
328 *
329 * RETURN:      Status
330 *
331 * DESCRIPTION: Read or Write a single datum of a field. The field_type is
332 *              demultiplexed here to handle the different types of fields
333 *              (buffer_field, region_field, index_field, bank_field)
334 *
335 ******************************************************************************/
336
337static acpi_status
338acpi_ex_field_datum_io(union acpi_operand_object *obj_desc,
339		       u32 field_datum_byte_offset, u64 *value, u32 read_write)
340{
341	acpi_status status;
342	u64 local_value;
343
344	ACPI_FUNCTION_TRACE_U32(ex_field_datum_io, field_datum_byte_offset);
345
346	if (read_write == ACPI_READ) {
347		if (!value) {
348			local_value = 0;
349
350			/* To support reads without saving return value */
351			value = &local_value;
352		}
353
354		/* Clear the entire return buffer first, [Very Important!] */
355
356		*value = 0;
357	}
358
359	/*
360	 * The four types of fields are:
361	 *
362	 * buffer_field - Read/write from/to a Buffer
363	 * region_field - Read/write from/to a Operation Region.
364	 * bank_field  - Write to a Bank Register, then read/write from/to an
365	 *               operation_region
366	 * index_field - Write to an Index Register, then read/write from/to a
367	 *               Data Register
368	 */
369	switch (obj_desc->common.type) {
370	case ACPI_TYPE_BUFFER_FIELD:
371		/*
372		 * If the buffer_field arguments have not been previously evaluated,
373		 * evaluate them now and save the results.
374		 */
375		if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
376			status = acpi_ds_get_buffer_field_arguments(obj_desc);
377			if (ACPI_FAILURE(status)) {
378				return_ACPI_STATUS(status);
379			}
380		}
381
382		if (read_write == ACPI_READ) {
383			/*
384			 * Copy the data from the source buffer.
385			 * Length is the field width in bytes.
386			 */
387			memcpy(value,
388			       (obj_desc->buffer_field.buffer_obj)->buffer.
389			       pointer +
390			       obj_desc->buffer_field.base_byte_offset +
391			       field_datum_byte_offset,
392			       obj_desc->common_field.access_byte_width);
393		} else {
394			/*
395			 * Copy the data to the target buffer.
396			 * Length is the field width in bytes.
397			 */
398			memcpy((obj_desc->buffer_field.buffer_obj)->buffer.
399			       pointer +
400			       obj_desc->buffer_field.base_byte_offset +
401			       field_datum_byte_offset, value,
402			       obj_desc->common_field.access_byte_width);
403		}
404
405		status = AE_OK;
406		break;
407
408	case ACPI_TYPE_LOCAL_BANK_FIELD:
 
409		/*
410		 * Ensure that the bank_value is not beyond the capacity of
411		 * the register
412		 */
413		if (acpi_ex_register_overflow(obj_desc->bank_field.bank_obj,
414					      (u64) obj_desc->bank_field.
415					      value)) {
416			return_ACPI_STATUS(AE_AML_REGISTER_LIMIT);
417		}
418
419		/*
420		 * For bank_fields, we must write the bank_value to the bank_register
421		 * (itself a region_field) before we can access the data.
422		 */
423		status =
424		    acpi_ex_insert_into_field(obj_desc->bank_field.bank_obj,
425					      &obj_desc->bank_field.value,
426					      sizeof(obj_desc->bank_field.
427						     value));
428		if (ACPI_FAILURE(status)) {
429			return_ACPI_STATUS(status);
430		}
431
432		/*
433		 * Now that the Bank has been selected, fall through to the
434		 * region_field case and write the datum to the Operation Region
435		 */
436
437		ACPI_FALLTHROUGH;
438
439	case ACPI_TYPE_LOCAL_REGION_FIELD:
440		/*
441		 * For simple region_fields, we just directly access the owning
442		 * Operation Region.
443		 */
444		status =
445		    acpi_ex_access_region(obj_desc, field_datum_byte_offset,
446					  value, read_write);
447		break;
448
449	case ACPI_TYPE_LOCAL_INDEX_FIELD:
 
450		/*
451		 * Ensure that the index_value is not beyond the capacity of
452		 * the register
453		 */
454		if (acpi_ex_register_overflow(obj_desc->index_field.index_obj,
455					      (u64) obj_desc->index_field.
456					      value)) {
457			return_ACPI_STATUS(AE_AML_REGISTER_LIMIT);
458		}
459
460		/* Write the index value to the index_register (itself a region_field) */
461
462		field_datum_byte_offset += obj_desc->index_field.value;
463
464		ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
465				  "Write to Index Register: Value %8.8X\n",
466				  field_datum_byte_offset));
467
468		status =
469		    acpi_ex_insert_into_field(obj_desc->index_field.index_obj,
470					      &field_datum_byte_offset,
471					      sizeof(field_datum_byte_offset));
472		if (ACPI_FAILURE(status)) {
473			return_ACPI_STATUS(status);
474		}
475
476		if (read_write == ACPI_READ) {
477
478			/* Read the datum from the data_register */
479
480			ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
481					  "Read from Data Register\n"));
482
483			status =
484			    acpi_ex_extract_from_field(obj_desc->index_field.
485						       data_obj, value,
486						       sizeof(u64));
487		} else {
488			/* Write the datum to the data_register */
489
490			ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
491					  "Write to Data Register: Value %8.8X%8.8X\n",
492					  ACPI_FORMAT_UINT64(*value)));
493
494			status =
495			    acpi_ex_insert_into_field(obj_desc->index_field.
496						      data_obj, value,
497						      sizeof(u64));
498		}
499		break;
500
501	default:
502
503		ACPI_ERROR((AE_INFO, "Wrong object type in field I/O %u",
504			    obj_desc->common.type));
505		status = AE_AML_INTERNAL;
506		break;
507	}
508
509	if (ACPI_SUCCESS(status)) {
510		if (read_write == ACPI_READ) {
511			ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
512					  "Value Read %8.8X%8.8X, Width %u\n",
513					  ACPI_FORMAT_UINT64(*value),
514					  obj_desc->common_field.
515					  access_byte_width));
516		} else {
517			ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
518					  "Value Written %8.8X%8.8X, Width %u\n",
519					  ACPI_FORMAT_UINT64(*value),
520					  obj_desc->common_field.
521					  access_byte_width));
522		}
523	}
524
525	return_ACPI_STATUS(status);
526}
527
528/*******************************************************************************
529 *
530 * FUNCTION:    acpi_ex_write_with_update_rule
531 *
532 * PARAMETERS:  obj_desc                - Field to be written
533 *              mask                    - bitmask within field datum
534 *              field_value             - Value to write
535 *              field_datum_byte_offset - Offset of datum within field
536 *
537 * RETURN:      Status
538 *
539 * DESCRIPTION: Apply the field update rule to a field write
540 *
541 ******************************************************************************/
542
543acpi_status
544acpi_ex_write_with_update_rule(union acpi_operand_object *obj_desc,
545			       u64 mask,
546			       u64 field_value, u32 field_datum_byte_offset)
547{
548	acpi_status status = AE_OK;
549	u64 merged_value;
550	u64 current_value;
551
552	ACPI_FUNCTION_TRACE_U32(ex_write_with_update_rule, mask);
553
554	/* Start with the new bits  */
555
556	merged_value = field_value;
557
558	/* If the mask is all ones, we don't need to worry about the update rule */
559
560	if (mask != ACPI_UINT64_MAX) {
561
562		/* Decode the update rule */
563
564		switch (obj_desc->common_field.
565			field_flags & AML_FIELD_UPDATE_RULE_MASK) {
566		case AML_FIELD_UPDATE_PRESERVE:
567			/*
568			 * Check if update rule needs to be applied (not if mask is all
569			 * ones)  The left shift drops the bits we want to ignore.
570			 */
571			if ((~mask << (ACPI_MUL_8(sizeof(mask)) -
572				       ACPI_MUL_8(obj_desc->common_field.
573						  access_byte_width))) != 0) {
574				/*
575				 * Read the current contents of the byte/word/dword containing
576				 * the field, and merge with the new field value.
577				 */
578				status =
579				    acpi_ex_field_datum_io(obj_desc,
580							   field_datum_byte_offset,
581							   &current_value,
582							   ACPI_READ);
583				if (ACPI_FAILURE(status)) {
584					return_ACPI_STATUS(status);
585				}
586
587				merged_value |= (current_value & ~mask);
588			}
589			break;
590
591		case AML_FIELD_UPDATE_WRITE_AS_ONES:
592
593			/* Set positions outside the field to all ones */
594
595			merged_value |= ~mask;
596			break;
597
598		case AML_FIELD_UPDATE_WRITE_AS_ZEROS:
599
600			/* Set positions outside the field to all zeros */
601
602			merged_value &= mask;
603			break;
604
605		default:
606
607			ACPI_ERROR((AE_INFO,
608				    "Unknown UpdateRule value: 0x%X",
609				    (obj_desc->common_field.field_flags &
 
610				     AML_FIELD_UPDATE_RULE_MASK)));
611			return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
612		}
613	}
614
615	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
616			  "Mask %8.8X%8.8X, DatumOffset %X, Width %X, "
617			  "Value %8.8X%8.8X, MergedValue %8.8X%8.8X\n",
618			  ACPI_FORMAT_UINT64(mask),
619			  field_datum_byte_offset,
620			  obj_desc->common_field.access_byte_width,
621			  ACPI_FORMAT_UINT64(field_value),
622			  ACPI_FORMAT_UINT64(merged_value)));
623
624	/* Write the merged value */
625
626	status =
627	    acpi_ex_field_datum_io(obj_desc, field_datum_byte_offset,
628				   &merged_value, ACPI_WRITE);
629
630	return_ACPI_STATUS(status);
631}
632
633/*******************************************************************************
634 *
635 * FUNCTION:    acpi_ex_extract_from_field
636 *
637 * PARAMETERS:  obj_desc            - Field to be read
638 *              buffer              - Where to store the field data
639 *              buffer_length       - Length of Buffer
640 *
641 * RETURN:      Status
642 *
643 * DESCRIPTION: Retrieve the current value of the given field
644 *
645 ******************************************************************************/
646
647acpi_status
648acpi_ex_extract_from_field(union acpi_operand_object *obj_desc,
649			   void *buffer, u32 buffer_length)
650{
651	acpi_status status;
652	u64 raw_datum;
653	u64 merged_datum;
654	u32 field_offset = 0;
655	u32 buffer_offset = 0;
656	u32 buffer_tail_bits;
657	u32 datum_count;
658	u32 field_datum_count;
659	u32 access_bit_width;
660	u32 i;
661
662	ACPI_FUNCTION_TRACE(ex_extract_from_field);
663
664	/* Validate target buffer and clear it */
665
666	if (buffer_length <
667	    ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.bit_length)) {
668		ACPI_ERROR((AE_INFO,
669			    "Field size %u (bits) is too large for buffer (%u)",
670			    obj_desc->common_field.bit_length, buffer_length));
671
672		return_ACPI_STATUS(AE_BUFFER_OVERFLOW);
673	}
674
675	memset(buffer, 0, buffer_length);
676	access_bit_width = ACPI_MUL_8(obj_desc->common_field.access_byte_width);
677
678	/* Handle the simple case here */
679
680	if ((obj_desc->common_field.start_field_bit_offset == 0) &&
681	    (obj_desc->common_field.bit_length == access_bit_width)) {
682		if (buffer_length >= sizeof(u64)) {
683			status =
684			    acpi_ex_field_datum_io(obj_desc, 0, buffer,
685						   ACPI_READ);
686		} else {
687			/* Use raw_datum (u64) to handle buffers < 64 bits */
688
689			status =
690			    acpi_ex_field_datum_io(obj_desc, 0, &raw_datum,
691						   ACPI_READ);
692			memcpy(buffer, &raw_datum, buffer_length);
693		}
694
695		return_ACPI_STATUS(status);
696	}
697
698/* TBD: Move to common setup code */
699
700	/* Field algorithm is limited to sizeof(u64), truncate if needed */
701
702	if (obj_desc->common_field.access_byte_width > sizeof(u64)) {
703		obj_desc->common_field.access_byte_width = sizeof(u64);
704		access_bit_width = sizeof(u64) * 8;
705	}
706
707	/* Compute the number of datums (access width data items) */
708
709	datum_count =
710	    ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length,
711			     access_bit_width);
712
713	field_datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length +
714					     obj_desc->common_field.
715					     start_field_bit_offset,
716					     access_bit_width);
717
718	/* Priming read from the field */
719
720	status =
721	    acpi_ex_field_datum_io(obj_desc, field_offset, &raw_datum,
722				   ACPI_READ);
723	if (ACPI_FAILURE(status)) {
724		return_ACPI_STATUS(status);
725	}
726	merged_datum =
727	    raw_datum >> obj_desc->common_field.start_field_bit_offset;
728
729	/* Read the rest of the field */
730
731	for (i = 1; i < field_datum_count; i++) {
732
733		/* Get next input datum from the field */
734
735		field_offset += obj_desc->common_field.access_byte_width;
736		status =
737		    acpi_ex_field_datum_io(obj_desc, field_offset, &raw_datum,
738					   ACPI_READ);
739		if (ACPI_FAILURE(status)) {
740			return_ACPI_STATUS(status);
741		}
742
743		/*
744		 * Merge with previous datum if necessary.
745		 *
746		 * Note: Before the shift, check if the shift value will be larger than
747		 * the integer size. If so, there is no need to perform the operation.
748		 * This avoids the differences in behavior between different compilers
749		 * concerning shift values larger than the target data width.
750		 */
751		if (access_bit_width -
752		    obj_desc->common_field.start_field_bit_offset <
753		    ACPI_INTEGER_BIT_SIZE) {
754			merged_datum |=
755			    raw_datum << (access_bit_width -
756					  obj_desc->common_field.
757					  start_field_bit_offset);
758		}
759
760		if (i == datum_count) {
761			break;
762		}
763
764		/* Write merged datum to target buffer */
765
766		memcpy(((char *)buffer) + buffer_offset, &merged_datum,
767		       ACPI_MIN(obj_desc->common_field.access_byte_width,
768				buffer_length - buffer_offset));
769
770		buffer_offset += obj_desc->common_field.access_byte_width;
771		merged_datum =
772		    raw_datum >> obj_desc->common_field.start_field_bit_offset;
773	}
774
775	/* Mask off any extra bits in the last datum */
776
777	buffer_tail_bits = obj_desc->common_field.bit_length % access_bit_width;
778	if (buffer_tail_bits) {
779		merged_datum &= ACPI_MASK_BITS_ABOVE(buffer_tail_bits);
780	}
781
782	/* Write the last datum to the buffer */
783
784	memcpy(((char *)buffer) + buffer_offset, &merged_datum,
785	       ACPI_MIN(obj_desc->common_field.access_byte_width,
786			buffer_length - buffer_offset));
787
788	return_ACPI_STATUS(AE_OK);
789}
790
791/*******************************************************************************
792 *
793 * FUNCTION:    acpi_ex_insert_into_field
794 *
795 * PARAMETERS:  obj_desc            - Field to be written
796 *              buffer              - Data to be written
797 *              buffer_length       - Length of Buffer
798 *
799 * RETURN:      Status
800 *
801 * DESCRIPTION: Store the Buffer contents into the given field
802 *
803 ******************************************************************************/
804
805acpi_status
806acpi_ex_insert_into_field(union acpi_operand_object *obj_desc,
807			  void *buffer, u32 buffer_length)
808{
809	void *new_buffer;
810	acpi_status status;
811	u64 mask;
812	u64 width_mask;
813	u64 merged_datum;
814	u64 raw_datum = 0;
815	u32 field_offset = 0;
816	u32 buffer_offset = 0;
817	u32 buffer_tail_bits;
818	u32 datum_count;
819	u32 field_datum_count;
820	u32 access_bit_width;
821	u32 required_length;
822	u32 i;
823
824	ACPI_FUNCTION_TRACE(ex_insert_into_field);
825
826	/* Validate input buffer */
827
828	new_buffer = NULL;
829	required_length =
830	    ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.bit_length);
831
832	/*
833	 * We must have a buffer that is at least as long as the field
834	 * we are writing to. This is because individual fields are
835	 * indivisible and partial writes are not supported -- as per
836	 * the ACPI specification.
837	 */
838	if (buffer_length < required_length) {
839
840		/* We need to create a new buffer */
841
842		new_buffer = ACPI_ALLOCATE_ZEROED(required_length);
843		if (!new_buffer) {
844			return_ACPI_STATUS(AE_NO_MEMORY);
845		}
846
847		/*
848		 * Copy the original data to the new buffer, starting
849		 * at Byte zero. All unused (upper) bytes of the
850		 * buffer will be 0.
851		 */
852		memcpy((char *)new_buffer, (char *)buffer, buffer_length);
853		buffer = new_buffer;
854		buffer_length = required_length;
855	}
856
857/* TBD: Move to common setup code */
858
859	/* Algo is limited to sizeof(u64), so cut the access_byte_width */
860	if (obj_desc->common_field.access_byte_width > sizeof(u64)) {
861		obj_desc->common_field.access_byte_width = sizeof(u64);
862	}
863
864	access_bit_width = ACPI_MUL_8(obj_desc->common_field.access_byte_width);
865
866	/* Create the bitmasks used for bit insertion */
 
 
 
 
 
 
 
 
 
867
868	width_mask = ACPI_MASK_BITS_ABOVE_64(access_bit_width);
869	mask = width_mask &
870	    ACPI_MASK_BITS_BELOW(obj_desc->common_field.start_field_bit_offset);
871
872	/* Compute the number of datums (access width data items) */
873
874	datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length,
875				       access_bit_width);
876
877	field_datum_count = ACPI_ROUND_UP_TO(obj_desc->common_field.bit_length +
878					     obj_desc->common_field.
879					     start_field_bit_offset,
880					     access_bit_width);
881
882	/* Get initial Datum from the input buffer */
883
884	memcpy(&raw_datum, buffer,
885	       ACPI_MIN(obj_desc->common_field.access_byte_width,
886			buffer_length - buffer_offset));
887
888	merged_datum =
889	    raw_datum << obj_desc->common_field.start_field_bit_offset;
890
891	/* Write the entire field */
892
893	for (i = 1; i < field_datum_count; i++) {
894
895		/* Write merged datum to the target field */
896
897		merged_datum &= mask;
898		status =
899		    acpi_ex_write_with_update_rule(obj_desc, mask, merged_datum,
900						   field_offset);
901		if (ACPI_FAILURE(status)) {
902			goto exit;
903		}
904
905		field_offset += obj_desc->common_field.access_byte_width;
906
907		/*
908		 * Start new output datum by merging with previous input datum
909		 * if necessary.
910		 *
911		 * Note: Before the shift, check if the shift value will be larger than
912		 * the integer size. If so, there is no need to perform the operation.
913		 * This avoids the differences in behavior between different compilers
914		 * concerning shift values larger than the target data width.
915		 */
916		if ((access_bit_width -
917		     obj_desc->common_field.start_field_bit_offset) <
918		    ACPI_INTEGER_BIT_SIZE) {
919			merged_datum =
920			    raw_datum >> (access_bit_width -
921					  obj_desc->common_field.
922					  start_field_bit_offset);
923		} else {
924			merged_datum = 0;
925		}
926
927		mask = width_mask;
928
929		if (i == datum_count) {
930			break;
931		}
932
933		/* Get the next input datum from the buffer */
934
935		buffer_offset += obj_desc->common_field.access_byte_width;
936		memcpy(&raw_datum, ((char *)buffer) + buffer_offset,
937		       ACPI_MIN(obj_desc->common_field.access_byte_width,
938				buffer_length - buffer_offset));
939
940		merged_datum |=
941		    raw_datum << obj_desc->common_field.start_field_bit_offset;
942	}
943
944	/* Mask off any extra bits in the last datum */
945
946	buffer_tail_bits = (obj_desc->common_field.bit_length +
947			    obj_desc->common_field.start_field_bit_offset) %
948	    access_bit_width;
949	if (buffer_tail_bits) {
950		mask &= ACPI_MASK_BITS_ABOVE(buffer_tail_bits);
951	}
952
953	/* Write the last datum to the field */
954
955	merged_datum &= mask;
956	status =
957	    acpi_ex_write_with_update_rule(obj_desc, mask, merged_datum,
958					   field_offset);
959
960exit:
961	/* Free temporary buffer if we used one */
962
963	if (new_buffer) {
964		ACPI_FREE(new_buffer);
965	}
966	return_ACPI_STATUS(status);
967}