drivers/acpi/executer/exprep.c

   1
   2 /******************************************************************************
   3  *
   4  * Module Name: exprep - ACPI AML (p-code) execution - field prep utilities
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2004, R. Byron Moore
  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
  46 #include <acpi/acpi.h>
  47 #include <acpi/acinterp.h>
  48 #include <acpi/amlcode.h>
  49 #include <acpi/acnamesp.h>
  50
  51
  52 #define _COMPONENT          ACPI_EXECUTER
  53          ACPI_MODULE_NAME    ("exprep")
  54
  55
  56 #ifdef ACPI_UNDER_DEVELOPMENT
  57 /*******************************************************************************
  58  *
  59  * FUNCTION:    acpi_ex_generate_access
  60  *
  61  * PARAMETERS:  field_bit_offset    - Start of field within parent region/buffer
  62  *              field_bit_length    - Length of field in bits
  63  *              region_length       - Length of parent in bytes
  64  *
  65  * RETURN:      Field granularity (8, 16, 32 or 64) and
  66  *              byte_alignment (1, 2, 3, or 4)
  67  *
  68  * DESCRIPTION: Generate an optimal access width for fields defined with the
  69  *              any_acc keyword.
  70  *
  71  * NOTE: Need to have the region_length in order to check for boundary
  72  *       conditions (end-of-region).  However, the region_length is a deferred
  73  *       operation.  Therefore, to complete this implementation, the generation
  74  *       of this access width must be deferred until the region length has
  75  *       been evaluated.
  76  *
  77  ******************************************************************************/
  78
  79 static u32
  80 acpi_ex_generate_access (
  81         u32                             field_bit_offset,
  82         u32                             field_bit_length,
  83         u32                             region_length)
  84 {
  85         u32                             field_byte_length;
  86         u32                             field_byte_offset;
  87         u32                             field_byte_end_offset;
  88         u32                             access_byte_width;
  89         u32                             field_start_offset;
  90         u32                             field_end_offset;
  91         u32                             minimum_access_width = 0xFFFFFFFF;
  92         u32                             minimum_accesses = 0xFFFFFFFF;
  93         u32                             accesses;
  94
  95
  96         ACPI_FUNCTION_TRACE ("ex_generate_access");
  97
  98
  99         /* Round Field start offset and length to "minimal" byte boundaries */
 100
 101         field_byte_offset  = ACPI_DIV_8 (ACPI_ROUND_DOWN (field_bit_offset, 8));
 102         field_byte_end_offset = ACPI_DIV_8 (ACPI_ROUND_UP (field_bit_length + field_bit_offset, 8));
 103         field_byte_length  = field_byte_end_offset - field_byte_offset;
 104
 105         ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 106                         "Bit length %d, Bit offset %d\n",
 107                         field_bit_length, field_bit_offset));
 108         ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 109                         "Byte Length %d, Byte Offset %d, End Offset %d\n",
 110                         field_byte_length, field_byte_offset, field_byte_end_offset));
 111
 112         /*
 113          * Iterative search for the maximum access width that is both aligned
 114          * and does not go beyond the end of the region
 115          *
 116          * Start at byte_acc and work upwards to qword_acc max. (1,2,4,8 bytes)
 117          */
 118         for (access_byte_width = 1; access_byte_width <= 8; access_byte_width <<= 1) {
 119                 /*
 120                  * 1) Round end offset up to next access boundary and make sure that this
 121                  *    does not go beyond the end of the parent region.
 122                  * 2) When the Access width is greater than the field_byte_length, we are done.
 123                  *    (This does not optimize for the perfectly aligned case yet).
 124                  */
 125                 if (ACPI_ROUND_UP (field_byte_end_offset, access_byte_width) <= region_length) {
 126                         field_start_offset = ACPI_ROUND_DOWN (field_byte_offset, access_byte_width) /
 127                                           access_byte_width;
 128                         field_end_offset = ACPI_ROUND_UP   ((field_byte_length + field_byte_offset),
 129                                           access_byte_width) / access_byte_width;
 130                         accesses         = field_end_offset - field_start_offset;
 131
 132                         ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 133                                         "access_width %d end is within region\n", access_byte_width));
 134                         ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 135                                         "Field Start %d, Field End %d -- requires %d accesses\n",
 136                                         field_start_offset, field_end_offset, accesses));
 137
 138                         /* Single access is optimal */
 139
 140                         if (accesses <= 1) {
 141                                 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 142                                                 "Entire field can be accessed with one operation of size %d\n",
 143                                                 access_byte_width));
 144                                 return_VALUE (access_byte_width);
 145                         }
 146
 147                         /*
 148                          * Fits in the region, but requires more than one read/write.
 149                          * try the next wider access on next iteration
 150                          */
 151                         if (accesses < minimum_accesses) {
 152                                 minimum_accesses   = accesses;
 153                                 minimum_access_width = access_byte_width;
 154                         }
 155                 }
 156                 else {
 157                         ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 158                                         "access_width %d end is NOT within region\n", access_byte_width));
 159                         if (access_byte_width == 1) {
 160                                 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 161                                                 "Field goes beyond end-of-region!\n"));
 162                                 return_VALUE (0);     /* Field does not fit in the region at all */
 163                         }
 164
 165                         /* This width goes beyond the end-of-region, back off to previous access */
 166
 167                         ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 168                                         "Backing off to previous optimal access width of %d\n",
 169                                         minimum_access_width));
 170                         return_VALUE (minimum_access_width);
 171                 }
 172         }
 173
 174         /* Could not read/write field with one operation, just use max access width */
 175
 176         ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 177                         "Cannot access field in one operation, using width 8\n"));
 178         return_VALUE (8);
 179 }
 180 #endif /* ACPI_UNDER_DEVELOPMENT */
 181
 182
 183 /*******************************************************************************
 184  *
 185  * FUNCTION:    acpi_ex_decode_field_access
 186  *
 187  * PARAMETERS:  Access          - Encoded field access bits
 188  *              Length          - Field length.
 189  *
 190  * RETURN:      Field granularity (8, 16, 32 or 64) and
 191  *              byte_alignment (1, 2, 3, or 4)
 192  *
 193  * DESCRIPTION: Decode the access_type bits of a field definition.
 194  *
 195  ******************************************************************************/
 196
 197 static u32
 198 acpi_ex_decode_field_access (
 199         union acpi_operand_object       *obj_desc,
 200         u8                              field_flags,
 201         u32                             *return_byte_alignment)
 202 {
 203         u32                             access;
 204         u32                             byte_alignment;
 205         u32                             bit_length;
 206
 207
 208         ACPI_FUNCTION_TRACE ("ex_decode_field_access");
 209
 210
 211         access = (field_flags & AML_FIELD_ACCESS_TYPE_MASK);
 212
 213         switch (access) {
 214         case AML_FIELD_ACCESS_ANY:
 215
 216 #ifdef ACPI_UNDER_DEVELOPMENT
 217                 byte_alignment = acpi_ex_generate_access (obj_desc->common_field.start_field_bit_offset,
 218                                  obj_desc->common_field.bit_length,
 219                                  0xFFFFFFFF /* Temp until we pass region_length as param */);
 220                 bit_length = byte_alignment * 8;
 221 #endif
 222
 223                 byte_alignment = 1;
 224                 bit_length = 8;
 225                 break;
 226
 227         case AML_FIELD_ACCESS_BYTE:
 228         case AML_FIELD_ACCESS_BUFFER:   /* ACPI 2.0 (SMBus Buffer) */
 229                 byte_alignment = 1;
 230                 bit_length    = 8;
 231                 break;
 232
 233         case AML_FIELD_ACCESS_WORD:
 234                 byte_alignment = 2;
 235                 bit_length    = 16;
 236                 break;
 237
 238         case AML_FIELD_ACCESS_DWORD:
 239                 byte_alignment = 4;
 240                 bit_length    = 32;
 241                 break;
 242
 243         case AML_FIELD_ACCESS_QWORD:    /* ACPI 2.0 */
 244                 byte_alignment = 8;
 245                 bit_length    = 64;
 246                 break;
 247
 248         default:
 249                 /* Invalid field access type */
 250
 251                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 252                         "Unknown field access type %X\n",
 253                         access));
 254                 return_VALUE (0);
 255         }
 256
 257         if (ACPI_GET_OBJECT_TYPE (obj_desc) == ACPI_TYPE_BUFFER_FIELD) {
 258                 /*
 259                  * buffer_field access can be on any byte boundary, so the
 260                  * byte_alignment is always 1 byte -- regardless of any byte_alignment
 261                  * implied by the field access type.
 262                  */
 263                 byte_alignment = 1;
 264         }
 265
 266         *return_byte_alignment = byte_alignment;
 267         return_VALUE (bit_length);
 268 }
 269
 270
 271 /*******************************************************************************
 272  *
 273  * FUNCTION:    acpi_ex_prep_common_field_object
 274  *
 275  * PARAMETERS:  obj_desc            - The field object
 276  *              field_flags         - Access, lock_rule, and update_rule.
 277  *                                    The format of a field_flag is described
 278  *                                    in the ACPI specification
 279  *              field_bit_position  - Field start position
 280  *              field_bit_length    - Field length in number of bits
 281  *
 282  * RETURN:      Status
 283  *
 284  * DESCRIPTION: Initialize the areas of the field object that are common
 285  *              to the various types of fields.  Note: This is very "sensitive"
 286  *              code because we are solving the general case for field
 287  *              alignment.
 288  *
 289  ******************************************************************************/
 290
 291 acpi_status
 292 acpi_ex_prep_common_field_object (
 293         union acpi_operand_object       *obj_desc,
 294         u8                              field_flags,
 295         u8                              field_attribute,
 296         u32                             field_bit_position,
 297         u32                             field_bit_length)
 298 {
 299         u32                             access_bit_width;
 300         u32                             byte_alignment;
 301         u32                             nearest_byte_address;
 302
 303
 304         ACPI_FUNCTION_TRACE ("ex_prep_common_field_object");
 305
 306
 307         /*
 308          * Note: the structure being initialized is the
 309          * ACPI_COMMON_FIELD_INFO;  No structure fields outside of the common
 310          * area are initialized by this procedure.
 311          */
 312         obj_desc->common_field.field_flags = field_flags;
 313         obj_desc->common_field.attribute = field_attribute;
 314         obj_desc->common_field.bit_length = field_bit_length;
 315
 316         /*
 317          * Decode the access type so we can compute offsets.  The access type gives
 318          * two pieces of information - the width of each field access and the
 319          * necessary byte_alignment (address granularity) of the access.
 320          *
 321          * For any_acc, the access_bit_width is the largest width that is both
 322          * necessary and possible in an attempt to access the whole field in one
 323          * I/O operation.  However, for any_acc, the byte_alignment is always one
 324          * byte.
 325          *
 326          * For all Buffer Fields, the byte_alignment is always one byte.
 327          *
 328          * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is
 329          * the same (equivalent) as the byte_alignment.
 330          */
 331         access_bit_width = acpi_ex_decode_field_access (obj_desc, field_flags,
 332                           &byte_alignment);
 333         if (!access_bit_width) {
 334                 return_ACPI_STATUS (AE_AML_OPERAND_VALUE);
 335         }
 336
 337         /* Setup width (access granularity) fields */
 338
 339         obj_desc->common_field.access_byte_width = (u8)
 340                         ACPI_DIV_8 (access_bit_width); /* 1, 2, 4,  8 */
 341
 342         /*
 343          * base_byte_offset is the address of the start of the field within the
 344          * region.  It is the byte address of the first *datum* (field-width data
 345          * unit) of the field. (i.e., the first datum that contains at least the
 346          * first *bit* of the field.)
 347          *
 348          * Note: byte_alignment is always either equal to the access_bit_width or 8
 349          * (Byte access), and it defines the addressing granularity of the parent
 350          * region or buffer.
 351          */
 352         nearest_byte_address =
 353                         ACPI_ROUND_BITS_DOWN_TO_BYTES (field_bit_position);
 354         obj_desc->common_field.base_byte_offset = (u32)
 355                         ACPI_ROUND_DOWN (nearest_byte_address, byte_alignment);
 356
 357         /*
 358          * start_field_bit_offset is the offset of the first bit of the field within
 359          * a field datum.
 360          */
 361         obj_desc->common_field.start_field_bit_offset = (u8)
 362                 (field_bit_position - ACPI_MUL_8 (obj_desc->common_field.base_byte_offset));
 363
 364         /*
 365          * Valid bits -- the number of bits that compose a partial datum,
 366          * 1) At the end of the field within the region (arbitrary starting bit
 367          *    offset)
 368          * 2) At the end of a buffer used to contain the field (starting offset
 369          *    always zero)
 370          */
 371         obj_desc->common_field.end_field_valid_bits = (u8)
 372                 ((obj_desc->common_field.start_field_bit_offset + field_bit_length) %
 373                                   access_bit_width);
 374         /* start_buffer_bit_offset always = 0 */
 375
 376         obj_desc->common_field.end_buffer_valid_bits = (u8)
 377                 (field_bit_length % access_bit_width);
 378
 379         /*
 380          * datum_valid_bits is the number of valid field bits in the first
 381          * field datum.
 382          */
 383         obj_desc->common_field.datum_valid_bits  = (u8)
 384                 (access_bit_width - obj_desc->common_field.start_field_bit_offset);
 385
 386         /*
 387          * Does the entire field fit within a single field access element? (datum)
 388          * (i.e., without crossing a datum boundary)
 389          */
 390         if ((obj_desc->common_field.start_field_bit_offset + field_bit_length) <=
 391                         (u16) access_bit_width) {
 392                 obj_desc->common.flags |= AOPOBJ_SINGLE_DATUM;
 393         }
 394
 395         return_ACPI_STATUS (AE_OK);
 396 }
 397
 398
 399 /*******************************************************************************
 400  *
 401  * FUNCTION:    acpi_ex_prep_field_value
 402  *
 403  * PARAMETERS:  Node                - Owning Node
 404  *              region_node         - Region in which field is being defined
 405  *              field_flags         - Access, lock_rule, and update_rule.
 406  *              field_bit_position  - Field start position
 407  *              field_bit_length    - Field length in number of bits
 408  *
 409  * RETURN:      Status
 410  *
 411  * DESCRIPTION: Construct an union acpi_operand_object of type def_field and
 412  *              connect it to the parent Node.
 413  *
 414  ******************************************************************************/
 415
 416 acpi_status
 417 acpi_ex_prep_field_value (
 418         struct acpi_create_field_info   *info)
 419 {
 420         union acpi_operand_object       *obj_desc;
 421         u32                             type;
 422         acpi_status                     status;
 423
 424
 425         ACPI_FUNCTION_TRACE ("ex_prep_field_value");
 426
 427
 428         /* Parameter validation */
 429
 430         if (info->field_type != ACPI_TYPE_LOCAL_INDEX_FIELD) {
 431                 if (!info->region_node) {
 432                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Null region_node\n"));
 433                         return_ACPI_STATUS (AE_AML_NO_OPERAND);
 434                 }
 435
 436                 type = acpi_ns_get_type (info->region_node);
 437                 if (type != ACPI_TYPE_REGION) {
 438                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 439                                 "Needed Region, found type %X (%s)\n",
 440                                 type, acpi_ut_get_type_name (type)));
 441
 442                         return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
 443                 }
 444         }
 445
 446         /* Allocate a new field object */
 447
 448         obj_desc = acpi_ut_create_internal_object (info->field_type);
 449         if (!obj_desc) {
 450                 return_ACPI_STATUS (AE_NO_MEMORY);
 451         }
 452
 453         /* Initialize areas of the object that are common to all fields */
 454
 455         obj_desc->common_field.node = info->field_node;
 456         status = acpi_ex_prep_common_field_object (obj_desc, info->field_flags,
 457                          info->attribute, info->field_bit_position, info->field_bit_length);
 458         if (ACPI_FAILURE (status)) {
 459                 acpi_ut_delete_object_desc (obj_desc);
 460                 return_ACPI_STATUS (status);
 461         }
 462
 463         /* Initialize areas of the object that are specific to the field type */
 464
 465         switch (info->field_type) {
 466         case ACPI_TYPE_LOCAL_REGION_FIELD:
 467
 468                 obj_desc->field.region_obj   = acpi_ns_get_attached_object (info->region_node);
 469
 470                 /* An additional reference for the container */
 471
 472                 acpi_ut_add_reference (obj_desc->field.region_obj);
 473
 474                 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 475                         "region_field: bit_off %X, Off %X, Gran %X, Region %p\n",
 476                         obj_desc->field.start_field_bit_offset, obj_desc->field.base_byte_offset,
 477                         obj_desc->field.access_byte_width, obj_desc->field.region_obj));
 478                 break;
 479
 480
 481         case ACPI_TYPE_LOCAL_BANK_FIELD:
 482
 483                 obj_desc->bank_field.value   = info->bank_value;
 484                 obj_desc->bank_field.region_obj = acpi_ns_get_attached_object (info->region_node);
 485                 obj_desc->bank_field.bank_obj = acpi_ns_get_attached_object (info->register_node);
 486
 487                 /* An additional reference for the attached objects */
 488
 489                 acpi_ut_add_reference (obj_desc->bank_field.region_obj);
 490                 acpi_ut_add_reference (obj_desc->bank_field.bank_obj);
 491
 492                 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 493                         "Bank Field: bit_off %X, Off %X, Gran %X, Region %p, bank_reg %p\n",
 494                         obj_desc->bank_field.start_field_bit_offset,
 495                         obj_desc->bank_field.base_byte_offset,
 496                         obj_desc->field.access_byte_width,
 497                         obj_desc->bank_field.region_obj,
 498                         obj_desc->bank_field.bank_obj));
 499                 break;
 500
 501
 502         case ACPI_TYPE_LOCAL_INDEX_FIELD:
 503
 504                 obj_desc->index_field.index_obj = acpi_ns_get_attached_object (info->register_node);
 505                 obj_desc->index_field.data_obj = acpi_ns_get_attached_object (info->data_register_node);
 506                 obj_desc->index_field.value  = (u32)
 507                         (info->field_bit_position / ACPI_MUL_8 (obj_desc->field.access_byte_width));
 508
 509                 if (!obj_desc->index_field.data_obj || !obj_desc->index_field.index_obj) {
 510                         ACPI_REPORT_ERROR (("Null Index Object during field prep\n"));
 511                         return_ACPI_STATUS (AE_AML_INTERNAL);
 512                 }
 513
 514                 /* An additional reference for the attached objects */
 515
 516                 acpi_ut_add_reference (obj_desc->index_field.data_obj);
 517                 acpi_ut_add_reference (obj_desc->index_field.index_obj);
 518
 519                 ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
 520                         "index_field: bit_off %X, Off %X, Value %X, Gran %X, Index %p, Data %p\n",
 521                         obj_desc->index_field.start_field_bit_offset,
 522                         obj_desc->index_field.base_byte_offset,
 523                         obj_desc->index_field.value,
 524                         obj_desc->field.access_byte_width,
 525                         obj_desc->index_field.index_obj,
 526                         obj_desc->index_field.data_obj));
 527                 break;
 528
 529         default:
 530                 /* No other types should get here */
 531                 break;
 532         }
 533
 534         /*
 535          * Store the constructed descriptor (obj_desc) into the parent Node,
 536          * preserving the current type of that named_obj.
 537          */
 538         status = acpi_ns_attach_object (info->field_node, obj_desc,
 539                           acpi_ns_get_type (info->field_node));
 540
 541         ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD, "Set named_obj %p [%4.4s], obj_desc %p\n",
 542                         info->field_node, acpi_ut_get_node_name (info->field_node), obj_desc));
 543
 544         /* Remove local reference to the object */
 545
 546         acpi_ut_remove_reference (obj_desc);
 547         return_ACPI_STATUS (status);
 548 }
 549