drivers/acpi/executer/exoparg1.c

   1
   2 /******************************************************************************
   3  *
   4  * Module Name: exoparg1 - AML execution - opcodes with 1 argument
   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/acparser.h>
  48 #include <acpi/acdispat.h>
  49 #include <acpi/acinterp.h>
  50 #include <acpi/amlcode.h>
  51 #include <acpi/acnamesp.h>
  52
  53
  54 #define _COMPONENT          ACPI_EXECUTER
  55          ACPI_MODULE_NAME    ("exoparg1")
  56
  57
  58 /*!
  59  * Naming convention for AML interpreter execution routines.
  60  *
  61  * The routines that begin execution of AML opcodes are named with a common
  62  * convention based upon the number of arguments, the number of target operands,
  63  * and whether or not a value is returned:
  64  *
  65  *      AcpiExOpcode_xA_yT_zR
  66  *
  67  * Where:
  68  *
  69  * xA - ARGUMENTS:    The number of arguments (input operands) that are
  70  *                    required for this opcode type (1 through 6 args).
  71  * yT - TARGETS:      The number of targets (output operands) that are required
  72  *                    for this opcode type (0, 1, or 2 targets).
  73  * zR - RETURN VALUE: Indicates whether this opcode type returns a value
  74  *                    as the function return (0 or 1).
  75  *
  76  * The AcpiExOpcode* functions are called via the Dispatcher component with
  77  * fully resolved operands.
  78 !*/
  79
  80 /*******************************************************************************
  81  *
  82  * FUNCTION:    acpi_ex_opcode_1A_0T_0R
  83  *
  84  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
  85  *
  86  * RETURN:      Status
  87  *
  88  * DESCRIPTION: Execute Type 1 monadic operator with numeric operand on
  89  *              object stack
  90  *
  91  ******************************************************************************/
  92
  93 acpi_status
  94 acpi_ex_opcode_1A_0T_0R (
  95         struct acpi_walk_state          *walk_state)
  96 {
  97         union acpi_operand_object       **operand = &walk_state->operands[0];
  98         acpi_status                     status = AE_OK;
  99
 100
 101         ACPI_FUNCTION_TRACE_STR ("ex_opcode_1A_0T_0R", acpi_ps_get_opcode_name (walk_state->opcode));
 102
 103
 104         /* Examine the AML opcode */
 105
 106         switch (walk_state->opcode) {
 107         case AML_RELEASE_OP:    /*  Release (mutex_object) */
 108
 109                 status = acpi_ex_release_mutex (operand[0], walk_state);
 110                 break;
 111
 112
 113         case AML_RESET_OP:      /*  Reset (event_object) */
 114
 115                 status = acpi_ex_system_reset_event (operand[0]);
 116                 break;
 117
 118
 119         case AML_SIGNAL_OP:     /*  Signal (event_object) */
 120
 121                 status = acpi_ex_system_signal_event (operand[0]);
 122                 break;
 123
 124
 125         case AML_SLEEP_OP:      /*  Sleep (msec_time) */
 126
 127                 status = acpi_ex_system_do_suspend ((u32) operand[0]->integer.value);
 128                 break;
 129
 130
 131         case AML_STALL_OP:      /*  Stall (usec_time) */
 132
 133                 status = acpi_ex_system_do_stall ((u32) operand[0]->integer.value);
 134                 break;
 135
 136
 137         case AML_UNLOAD_OP:     /*  Unload (Handle) */
 138
 139                 status = acpi_ex_unload_table (operand[0]);
 140                 break;
 141
 142
 143         default:                /*  Unknown opcode  */
 144
 145                 ACPI_REPORT_ERROR (("acpi_ex_opcode_1A_0T_0R: Unknown opcode %X\n",
 146                         walk_state->opcode));
 147                 status = AE_AML_BAD_OPCODE;
 148                 break;
 149         }
 150
 151         return_ACPI_STATUS (status);
 152 }
 153
 154
 155 /*******************************************************************************
 156  *
 157  * FUNCTION:    acpi_ex_opcode_1A_1T_0R
 158  *
 159  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
 160  *
 161  * RETURN:      Status
 162  *
 163  * DESCRIPTION: Execute opcode with one argument, one target, and no
 164  *              return value.
 165  *
 166  ******************************************************************************/
 167
 168 acpi_status
 169 acpi_ex_opcode_1A_1T_0R (
 170         struct acpi_walk_state          *walk_state)
 171 {
 172         acpi_status                     status = AE_OK;
 173         union acpi_operand_object       **operand = &walk_state->operands[0];
 174
 175
 176         ACPI_FUNCTION_TRACE_STR ("ex_opcode_1A_1T_0R", acpi_ps_get_opcode_name (walk_state->opcode));
 177
 178
 179         /* Examine the AML opcode */
 180
 181         switch (walk_state->opcode) {
 182         case AML_LOAD_OP:
 183
 184                 status = acpi_ex_load_op (operand[0], operand[1], walk_state);
 185                 break;
 186
 187         default:                        /* Unknown opcode */
 188
 189                 ACPI_REPORT_ERROR (("acpi_ex_opcode_1A_1T_0R: Unknown opcode %X\n",
 190                         walk_state->opcode));
 191                 status = AE_AML_BAD_OPCODE;
 192                 goto cleanup;
 193         }
 194
 195
 196 cleanup:
 197
 198         return_ACPI_STATUS (status);
 199 }
 200
 201
 202 /*******************************************************************************
 203  *
 204  * FUNCTION:    acpi_ex_opcode_1A_1T_1R
 205  *
 206  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
 207  *
 208  * RETURN:      Status
 209  *
 210  * DESCRIPTION: Execute opcode with one argument, one target, and a
 211  *              return value.
 212  *
 213  ******************************************************************************/
 214
 215 acpi_status
 216 acpi_ex_opcode_1A_1T_1R (
 217         struct acpi_walk_state          *walk_state)
 218 {
 219         acpi_status                     status = AE_OK;
 220         union acpi_operand_object       **operand = &walk_state->operands[0];
 221         union acpi_operand_object       *return_desc = NULL;
 222         union acpi_operand_object       *return_desc2 = NULL;
 223         u32                             temp32;
 224         u32                             i;
 225         u32                             power_of_ten;
 226         acpi_integer                    digit;
 227
 228
 229         ACPI_FUNCTION_TRACE_STR ("ex_opcode_1A_1T_1R", acpi_ps_get_opcode_name (walk_state->opcode));
 230
 231
 232         /* Examine the AML opcode */
 233
 234         switch (walk_state->opcode) {
 235         case AML_BIT_NOT_OP:
 236         case AML_FIND_SET_LEFT_BIT_OP:
 237         case AML_FIND_SET_RIGHT_BIT_OP:
 238         case AML_FROM_BCD_OP:
 239         case AML_TO_BCD_OP:
 240         case AML_COND_REF_OF_OP:
 241
 242                 /* Create a return object of type Integer for these opcodes */
 243
 244                 return_desc = acpi_ut_create_internal_object (ACPI_TYPE_INTEGER);
 245                 if (!return_desc) {
 246                         status = AE_NO_MEMORY;
 247                         goto cleanup;
 248                 }
 249
 250                 switch (walk_state->opcode) {
 251                 case AML_BIT_NOT_OP:            /* Not (Operand, Result)  */
 252
 253                         return_desc->integer.value = ~operand[0]->integer.value;
 254                         break;
 255
 256
 257                 case AML_FIND_SET_LEFT_BIT_OP:  /* find_set_left_bit (Operand, Result) */
 258
 259                         return_desc->integer.value = operand[0]->integer.value;
 260
 261                         /*
 262                          * Acpi specification describes Integer type as a little
 263                          * endian unsigned value, so this boundary condition is valid.
 264                          */
 265                         for (temp32 = 0; return_desc->integer.value && temp32 < ACPI_INTEGER_BIT_SIZE; ++temp32) {
 266                                 return_desc->integer.value >>= 1;
 267                         }
 268
 269                         return_desc->integer.value = temp32;
 270                         break;
 271
 272
 273                 case AML_FIND_SET_RIGHT_BIT_OP: /* find_set_right_bit (Operand, Result) */
 274
 275                         return_desc->integer.value = operand[0]->integer.value;
 276
 277                         /*
 278                          * The Acpi specification describes Integer type as a little
 279                          * endian unsigned value, so this boundary condition is valid.
 280                          */
 281                         for (temp32 = 0; return_desc->integer.value && temp32 < ACPI_INTEGER_BIT_SIZE; ++temp32) {
 282                                 return_desc->integer.value <<= 1;
 283                         }
 284
 285                         /* Since the bit position is one-based, subtract from 33 (65) */
 286
 287                         return_desc->integer.value = temp32 == 0 ? 0 : (ACPI_INTEGER_BIT_SIZE + 1) - temp32;
 288                         break;
 289
 290
 291                 case AML_FROM_BCD_OP:           /* from_bcd (BCDValue, Result) */
 292
 293                         /*
 294                          * The 64-bit ACPI integer can hold 16 4-bit BCD characters
 295                          * (if table is 32-bit, integer can hold 8 BCD characters)
 296                          * Convert each 4-bit BCD value
 297                          */
 298                         power_of_ten = 1;
 299                         return_desc->integer.value = 0;
 300                         digit = operand[0]->integer.value;
 301
 302                         /* Convert each BCD digit (each is one nybble wide) */
 303
 304                         for (i = 0; (i < acpi_gbl_integer_nybble_width) && (digit > 0); i++) {
 305                                 /* Get the least significant 4-bit BCD digit */
 306
 307                                 temp32 = ((u32) digit) & 0xF;
 308
 309                                 /* Check the range of the digit */
 310
 311                                 if (temp32 > 9) {
 312                                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 313                                                 "BCD digit too large (not decimal): 0x%X\n",
 314                                                 temp32));
 315
 316                                         status = AE_AML_NUMERIC_OVERFLOW;
 317                                         goto cleanup;
 318                                 }
 319
 320                                 /* Sum the digit into the result with the current power of 10 */
 321
 322                                 return_desc->integer.value += (((acpi_integer) temp32) * power_of_ten);
 323
 324                                 /* Shift to next BCD digit */
 325
 326                                 digit >>= 4;
 327
 328                                 /* Next power of 10 */
 329
 330                                 power_of_ten *= 10;
 331                         }
 332                         break;
 333
 334
 335                 case AML_TO_BCD_OP:             /* to_bcd (Operand, Result) */
 336
 337                         return_desc->integer.value = 0;
 338                         digit = operand[0]->integer.value;
 339
 340                         /* Each BCD digit is one nybble wide */
 341
 342                         for (i = 0; (i < acpi_gbl_integer_nybble_width) && (digit > 0); i++) {
 343                                 (void) acpi_ut_short_divide (&digit, 10, &digit, &temp32);
 344
 345                                 /* Insert the BCD digit that resides in the remainder from above */
 346
 347                                 return_desc->integer.value |= (((acpi_integer) temp32) << (i * 4));
 348                         }
 349
 350                         /* Overflow if there is any data left in Digit */
 351
 352                         if (digit > 0) {
 353                                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Integer too large to convert to BCD: %8.8X%8.8X\n",
 354                                                 ACPI_FORMAT_UINT64 (operand[0]->integer.value)));
 355                                 status = AE_AML_NUMERIC_OVERFLOW;
 356                                 goto cleanup;
 357                         }
 358                         break;
 359
 360
 361                 case AML_COND_REF_OF_OP:        /* cond_ref_of (source_object, Result) */
 362
 363                         /*
 364                          * This op is a little strange because the internal return value is
 365                          * different than the return value stored in the result descriptor
 366                          * (There are really two return values)
 367                          */
 368                         if ((struct acpi_namespace_node *) operand[0] == acpi_gbl_root_node) {
 369                                 /*
 370                                  * This means that the object does not exist in the namespace,
 371                                  * return FALSE
 372                                  */
 373                                 return_desc->integer.value = 0;
 374                                 goto cleanup;
 375                         }
 376
 377                         /* Get the object reference, store it, and remove our reference */
 378
 379                         status = acpi_ex_get_object_reference (operand[0], &return_desc2, walk_state);
 380                         if (ACPI_FAILURE (status)) {
 381                                 goto cleanup;
 382                         }
 383
 384                         status = acpi_ex_store (return_desc2, operand[1], walk_state);
 385                         acpi_ut_remove_reference (return_desc2);
 386
 387                         /* The object exists in the namespace, return TRUE */
 388
 389                         return_desc->integer.value = ACPI_INTEGER_MAX;
 390                         goto cleanup;
 391
 392
 393                 default:
 394                         /* No other opcodes get here */
 395                         break;
 396                 }
 397                 break;
 398
 399
 400         case AML_STORE_OP:              /* Store (Source, Target) */
 401
 402                 /*
 403                  * A store operand is typically a number, string, buffer or lvalue
 404                  * Be careful about deleting the source object,
 405                  * since the object itself may have been stored.
 406                  */
 407                 status = acpi_ex_store (operand[0], operand[1], walk_state);
 408                 if (ACPI_FAILURE (status)) {
 409                         return_ACPI_STATUS (status);
 410                 }
 411
 412                 /* It is possible that the Store already produced a return object */
 413
 414                 if (!walk_state->result_obj) {
 415                         /*
 416                          * Normally, we would remove a reference on the Operand[0] parameter;
 417                          * But since it is being used as the internal return object
 418                          * (meaning we would normally increment it), the two cancel out,
 419                          * and we simply don't do anything.
 420                          */
 421                         walk_state->result_obj = operand[0];
 422                         walk_state->operands[0] = NULL; /* Prevent deletion */
 423                 }
 424                 return_ACPI_STATUS (status);
 425
 426
 427         /*
 428          * ACPI 2.0 Opcodes
 429          */
 430         case AML_COPY_OP:               /* Copy (Source, Target) */
 431
 432                 status = acpi_ut_copy_iobject_to_iobject (operand[0], &return_desc, walk_state);
 433                 break;
 434
 435
 436         case AML_TO_DECSTRING_OP:       /* to_decimal_string (Data, Result) */
 437
 438                 status = acpi_ex_convert_to_string (operand[0], &return_desc, 10, ACPI_UINT32_MAX, walk_state);
 439                 break;
 440
 441
 442         case AML_TO_HEXSTRING_OP:       /* to_hex_string (Data, Result) */
 443
 444                 status = acpi_ex_convert_to_string (operand[0], &return_desc, 16, ACPI_UINT32_MAX, walk_state);
 445                 break;
 446
 447
 448         case AML_TO_BUFFER_OP:          /* to_buffer (Data, Result) */
 449
 450                 status = acpi_ex_convert_to_buffer (operand[0], &return_desc, walk_state);
 451                 break;
 452
 453
 454         case AML_TO_INTEGER_OP:         /* to_integer (Data, Result) */
 455
 456                 status = acpi_ex_convert_to_integer (operand[0], &return_desc, walk_state);
 457                 break;
 458
 459
 460         case AML_SHIFT_LEFT_BIT_OP:     /*  shift_left_bit (Source, bit_num) */
 461         case AML_SHIFT_RIGHT_BIT_OP:    /*  shift_right_bit (Source, bit_num) */
 462
 463                 /*
 464                  * These are two obsolete opcodes
 465                  */
 466                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "%s is obsolete and not implemented\n",
 467                                   acpi_ps_get_opcode_name (walk_state->opcode)));
 468                 status = AE_SUPPORT;
 469                 goto cleanup;
 470
 471
 472         default:                        /* Unknown opcode */
 473
 474                 ACPI_REPORT_ERROR (("acpi_ex_opcode_1A_1T_1R: Unknown opcode %X\n",
 475                         walk_state->opcode));
 476                 status = AE_AML_BAD_OPCODE;
 477                 goto cleanup;
 478         }
 479
 480         /*
 481          * Store the return value computed above into the target object
 482          */
 483         status = acpi_ex_store (return_desc, operand[1], walk_state);
 484
 485
 486 cleanup:
 487
 488         if (!walk_state->result_obj) {
 489                 walk_state->result_obj = return_desc;
 490         }
 491
 492         /* Delete return object on error */
 493
 494         if (ACPI_FAILURE (status)) {
 495                 acpi_ut_remove_reference (return_desc);
 496         }
 497
 498         return_ACPI_STATUS (status);
 499 }
 500
 501
 502 /*******************************************************************************
 503  *
 504  * FUNCTION:    acpi_ex_opcode_1A_0T_1R
 505  *
 506  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
 507  *
 508  * RETURN:      Status
 509  *
 510  * DESCRIPTION: Execute opcode with one argument, no target, and a return value
 511  *
 512  ******************************************************************************/
 513
 514 acpi_status
 515 acpi_ex_opcode_1A_0T_1R (
 516         struct acpi_walk_state          *walk_state)
 517 {
 518         union acpi_operand_object       **operand = &walk_state->operands[0];
 519         union acpi_operand_object       *temp_desc;
 520         union acpi_operand_object       *return_desc = NULL;
 521         acpi_status                     status = AE_OK;
 522         u32                             type;
 523         acpi_integer                    value;
 524
 525
 526         ACPI_FUNCTION_TRACE_STR ("ex_opcode_1A_0T_1R", acpi_ps_get_opcode_name (walk_state->opcode));
 527
 528
 529         /* Examine the AML opcode */
 530
 531         switch (walk_state->opcode) {
 532         case AML_LNOT_OP:               /* LNot (Operand) */
 533
 534                 return_desc = acpi_ut_create_internal_object (ACPI_TYPE_INTEGER);
 535                 if (!return_desc) {
 536                         status = AE_NO_MEMORY;
 537                         goto cleanup;
 538                 }
 539
 540                 return_desc->integer.value = !operand[0]->integer.value;
 541                 break;
 542
 543
 544         case AML_DECREMENT_OP:          /* Decrement (Operand)  */
 545         case AML_INCREMENT_OP:          /* Increment (Operand)  */
 546
 547                 /*
 548                  * Since we are expecting a Reference operand, it
 549                  * can be either a NS Node or an internal object.
 550                  */
 551                 return_desc = operand[0];
 552                 if (ACPI_GET_DESCRIPTOR_TYPE (operand[0]) == ACPI_DESC_TYPE_OPERAND) {
 553                         /* Internal reference object - prevent deletion */
 554
 555                         acpi_ut_add_reference (return_desc);
 556                 }
 557
 558                 /*
 559                  * Convert the return_desc Reference to a Number
 560                  * (This removes a reference on the return_desc object)
 561                  */
 562                 status = acpi_ex_resolve_operands (AML_LNOT_OP, &return_desc, walk_state);
 563                 if (ACPI_FAILURE (status)) {
 564                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "%s: bad operand(s) %s\n",
 565                                 acpi_ps_get_opcode_name (walk_state->opcode), acpi_format_exception(status)));
 566
 567                         goto cleanup;
 568                 }
 569
 570                 /*
 571                  * return_desc is now guaranteed to be an Integer object
 572                  * Do the actual increment or decrement
 573                  */
 574                 if (AML_INCREMENT_OP == walk_state->opcode) {
 575                         return_desc->integer.value++;
 576                 }
 577                 else {
 578                         return_desc->integer.value--;
 579                 }
 580
 581                 /* Store the result back in the original descriptor */
 582
 583                 status = acpi_ex_store (return_desc, operand[0], walk_state);
 584                 break;
 585
 586
 587         case AML_TYPE_OP:               /* object_type (source_object) */
 588
 589                 /* Get the type of the base object */
 590
 591                 status = acpi_ex_resolve_multiple (walk_state, operand[0], &type, NULL);
 592                 if (ACPI_FAILURE (status)) {
 593                         goto cleanup;
 594                 }
 595
 596                 /* Allocate a descriptor to hold the type. */
 597
 598                 return_desc = acpi_ut_create_internal_object (ACPI_TYPE_INTEGER);
 599                 if (!return_desc) {
 600                         status = AE_NO_MEMORY;
 601                         goto cleanup;
 602                 }
 603
 604                 return_desc->integer.value = type;
 605                 break;
 606
 607
 608         case AML_SIZE_OF_OP:            /* size_of (source_object) */
 609
 610                 /* Get the base object */
 611
 612                 status = acpi_ex_resolve_multiple (walk_state, operand[0], &type, &temp_desc);
 613                 if (ACPI_FAILURE (status)) {
 614                         goto cleanup;
 615                 }
 616
 617                 /*
 618                  * Type is guaranteed to be a buffer, string, or package at this
 619                  * point (even if the original operand was an object reference, it
 620                  * will be resolved and typechecked during operand resolution.)
 621                  */
 622                 switch (type) {
 623                 case ACPI_TYPE_BUFFER:
 624                         value = temp_desc->buffer.length;
 625                         break;
 626
 627                 case ACPI_TYPE_STRING:
 628                         value = temp_desc->string.length;
 629                         break;
 630
 631                 case ACPI_TYPE_PACKAGE:
 632                         value = temp_desc->package.count;
 633                         break;
 634
 635                 default:
 636                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "size_of, Not Buf/Str/Pkg - found type %s\n",
 637                                 acpi_ut_get_type_name (type)));
 638                         status = AE_AML_OPERAND_TYPE;
 639                         goto cleanup;
 640                 }
 641
 642                 /*
 643                  * Now that we have the size of the object, create a result
 644                  * object to hold the value
 645                  */
 646                 return_desc = acpi_ut_create_internal_object (ACPI_TYPE_INTEGER);
 647                 if (!return_desc) {
 648                         status = AE_NO_MEMORY;
 649                         goto cleanup;
 650                 }
 651
 652                 return_desc->integer.value = value;
 653                 break;
 654
 655
 656         case AML_REF_OF_OP:             /* ref_of (source_object) */
 657
 658                 status = acpi_ex_get_object_reference (operand[0], &return_desc, walk_state);
 659                 if (ACPI_FAILURE (status)) {
 660                         goto cleanup;
 661                 }
 662                 break;
 663
 664
 665         case AML_DEREF_OF_OP:           /* deref_of (obj_reference | String) */
 666
 667                 /* Check for a method local or argument, or standalone String */
 668
 669                 if (ACPI_GET_DESCRIPTOR_TYPE (operand[0]) != ACPI_DESC_TYPE_NAMED) {
 670                         switch (ACPI_GET_OBJECT_TYPE (operand[0])) {
 671                         case ACPI_TYPE_LOCAL_REFERENCE:
 672                                 /*
 673                                  * This is a deref_of (local_x | arg_x)
 674                                  *
 675                                  * Must resolve/dereference the local/arg reference first
 676                                  */
 677                                 switch (operand[0]->reference.opcode) {
 678                                 case AML_LOCAL_OP:
 679                                 case AML_ARG_OP:
 680
 681                                         /* Set Operand[0] to the value of the local/arg */
 682
 683                                         status = acpi_ds_method_data_get_value (operand[0]->reference.opcode,
 684                                                          operand[0]->reference.offset, walk_state, &temp_desc);
 685                                         if (ACPI_FAILURE (status)) {
 686                                                 goto cleanup;
 687                                         }
 688
 689                                         /*
 690                                          * Delete our reference to the input object and
 691                                          * point to the object just retrieved
 692                                          */
 693                                         acpi_ut_remove_reference (operand[0]);
 694                                         operand[0] = temp_desc;
 695                                         break;
 696
 697                                 case AML_REF_OF_OP:
 698
 699                                         /* Get the object to which the reference refers */
 700
 701                                         temp_desc = operand[0]->reference.object;
 702                                         acpi_ut_remove_reference (operand[0]);
 703                                         operand[0] = temp_desc;
 704                                         break;
 705
 706                                 default:
 707
 708                                         /* Must be an Index op - handled below */
 709                                         break;
 710                                 }
 711                                 break;
 712
 713
 714                         case ACPI_TYPE_STRING:
 715
 716                                 /*
 717                                  * This is a deref_of (String). The string is a reference to a named ACPI object.
 718                                  *
 719                                  * 1) Find the owning Node
 720                                  * 2) Dereference the node to an actual object.  Could be a Field, so we nee
 721                                  *    to resolve the node to a value.
 722                                  */
 723                                 status = acpi_ns_get_node_by_path (operand[0]->string.pointer,
 724                                                   walk_state->scope_info->scope.node, ACPI_NS_SEARCH_PARENT,
 725                                                   ACPI_CAST_INDIRECT_PTR (struct acpi_namespace_node, &return_desc));
 726                                 if (ACPI_FAILURE (status)) {
 727                                         goto cleanup;
 728                                 }
 729
 730                                 status = acpi_ex_resolve_node_to_value (
 731                                                   ACPI_CAST_INDIRECT_PTR (struct acpi_namespace_node, &return_desc), walk_state);
 732                                 goto cleanup;
 733
 734
 735                         default:
 736
 737                                 status = AE_AML_OPERAND_TYPE;
 738                                 goto cleanup;
 739                         }
 740                 }
 741
 742                 /* Operand[0] may have changed from the code above */
 743
 744                 if (ACPI_GET_DESCRIPTOR_TYPE (operand[0]) == ACPI_DESC_TYPE_NAMED) {
 745                         /*
 746                          * This is a deref_of (object_reference)
 747                          * Get the actual object from the Node (This is the dereference).
 748                          * -- This case may only happen when a local_x or arg_x is dereferenced above.
 749                          */
 750                         return_desc = acpi_ns_get_attached_object ((struct acpi_namespace_node *) operand[0]);
 751                 }
 752                 else {
 753                         /*
 754                          * This must be a reference object produced by either the Index() or
 755                          * ref_of() operator
 756                          */
 757                         switch (operand[0]->reference.opcode) {
 758                         case AML_INDEX_OP:
 759
 760                                 /*
 761                                  * The target type for the Index operator must be
 762                                  * either a Buffer or a Package
 763                                  */
 764                                 switch (operand[0]->reference.target_type) {
 765                                 case ACPI_TYPE_BUFFER_FIELD:
 766
 767                                         temp_desc = operand[0]->reference.object;
 768
 769                                         /*
 770                                          * Create a new object that contains one element of the
 771                                          * buffer -- the element pointed to by the index.
 772                                          *
 773                                          * NOTE: index into a buffer is NOT a pointer to a
 774                                          * sub-buffer of the main buffer, it is only a pointer to a
 775                                          * single element (byte) of the buffer!
 776                                          */
 777                                         return_desc = acpi_ut_create_internal_object (ACPI_TYPE_INTEGER);
 778                                         if (!return_desc) {
 779                                                 status = AE_NO_MEMORY;
 780                                                 goto cleanup;
 781                                         }
 782
 783                                         /*
 784                                          * Since we are returning the value of the buffer at the
 785                                          * indexed location, we don't need to add an additional
 786                                          * reference to the buffer itself.
 787                                          */
 788                                         return_desc->integer.value =
 789                                                 temp_desc->buffer.pointer[operand[0]->reference.offset];
 790                                         break;
 791
 792
 793                                 case ACPI_TYPE_PACKAGE:
 794
 795                                         /*
 796                                          * Return the referenced element of the package.  We must add
 797                                          * another reference to the referenced object, however.
 798                                          */
 799                                         return_desc = *(operand[0]->reference.where);
 800                                         if (!return_desc) {
 801                                                 /*
 802                                                  * We can't return a NULL dereferenced value.  This is
 803                                                  * an uninitialized package element and is thus a
 804                                                  * severe error.
 805                                                  */
 806                                                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "NULL package element obj %p\n",
 807                                                         operand[0]));
 808                                                 status = AE_AML_UNINITIALIZED_ELEMENT;
 809                                                 goto cleanup;
 810                                         }
 811
 812                                         acpi_ut_add_reference (return_desc);
 813                                         break;
 814
 815
 816                                 default:
 817
 818                                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Unknown Index target_type %X in obj %p\n",
 819                                                 operand[0]->reference.target_type, operand[0]));
 820                                         status = AE_AML_OPERAND_TYPE;
 821                                         goto cleanup;
 822                                 }
 823                                 break;
 824
 825
 826                         case AML_REF_OF_OP:
 827
 828                                 return_desc = operand[0]->reference.object;
 829
 830                                 if (ACPI_GET_DESCRIPTOR_TYPE (return_desc) == ACPI_DESC_TYPE_NAMED) {
 831
 832                                         return_desc = acpi_ns_get_attached_object ((struct acpi_namespace_node *) return_desc);
 833                                 }
 834
 835                                 /* Add another reference to the object! */
 836
 837                                 acpi_ut_add_reference (return_desc);
 838                                 break;
 839
 840
 841                         default:
 842                                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Unknown opcode in ref(%p) - %X\n",
 843                                         operand[0], operand[0]->reference.opcode));
 844
 845                                 status = AE_TYPE;
 846                                 goto cleanup;
 847                         }
 848                 }
 849                 break;
 850
 851
 852         default:
 853
 854                 ACPI_REPORT_ERROR (("acpi_ex_opcode_1A_0T_1R: Unknown opcode %X\n",
 855                         walk_state->opcode));
 856                 status = AE_AML_BAD_OPCODE;
 857                 goto cleanup;
 858         }
 859
 860
 861 cleanup:
 862
 863         /* Delete return object on error */
 864
 865         if (ACPI_FAILURE (status)) {
 866                 acpi_ut_remove_reference (return_desc);
 867         }
 868
 869         walk_state->result_obj = return_desc;
 870         return_ACPI_STATUS (status);
 871 }
 872