cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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exoparg1.c (27556B)


      1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
      2/******************************************************************************
      3 *
      4 * Module Name: exoparg1 - AML execution - opcodes with 1 argument
      5 *
      6 * Copyright (C) 2000 - 2022, Intel Corp.
      7 *
      8 *****************************************************************************/
      9
     10#include <acpi/acpi.h>
     11#include "accommon.h"
     12#include "acparser.h"
     13#include "acdispat.h"
     14#include "acinterp.h"
     15#include "amlcode.h"
     16#include "acnamesp.h"
     17
     18#define _COMPONENT          ACPI_EXECUTER
     19ACPI_MODULE_NAME("exoparg1")
     20
     21/*!
     22 * Naming convention for AML interpreter execution routines.
     23 *
     24 * The routines that begin execution of AML opcodes are named with a common
     25 * convention based upon the number of arguments, the number of target operands,
     26 * and whether or not a value is returned:
     27 *
     28 *      AcpiExOpcode_xA_yT_zR
     29 *
     30 * Where:
     31 *
     32 * xA - ARGUMENTS:    The number of arguments (input operands) that are
     33 *                    required for this opcode type (0 through 6 args).
     34 * yT - TARGETS:      The number of targets (output operands) that are required
     35 *                    for this opcode type (0, 1, or 2 targets).
     36 * zR - RETURN VALUE: Indicates whether this opcode type returns a value
     37 *                    as the function return (0 or 1).
     38 *
     39 * The AcpiExOpcode* functions are called via the Dispatcher component with
     40 * fully resolved operands.
     41!*/
     42/*******************************************************************************
     43 *
     44 * FUNCTION:    acpi_ex_opcode_0A_0T_1R
     45 *
     46 * PARAMETERS:  walk_state          - Current state (contains AML opcode)
     47 *
     48 * RETURN:      Status
     49 *
     50 * DESCRIPTION: Execute operator with no operands, one return value
     51 *
     52 ******************************************************************************/
     53acpi_status acpi_ex_opcode_0A_0T_1R(struct acpi_walk_state *walk_state)
     54{
     55	acpi_status status = AE_OK;
     56	union acpi_operand_object *return_desc = NULL;
     57
     58	ACPI_FUNCTION_TRACE_STR(ex_opcode_0A_0T_1R,
     59				acpi_ps_get_opcode_name(walk_state->opcode));
     60
     61	/* Examine the AML opcode */
     62
     63	switch (walk_state->opcode) {
     64	case AML_TIMER_OP:	/*  Timer () */
     65
     66		/* Create a return object of type Integer */
     67
     68		return_desc =
     69		    acpi_ut_create_integer_object(acpi_os_get_timer());
     70		if (!return_desc) {
     71			status = AE_NO_MEMORY;
     72			goto cleanup;
     73		}
     74		break;
     75
     76	default:		/*  Unknown opcode  */
     77
     78		ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
     79			    walk_state->opcode));
     80		status = AE_AML_BAD_OPCODE;
     81		break;
     82	}
     83
     84cleanup:
     85
     86	/* Delete return object on error */
     87
     88	if ((ACPI_FAILURE(status)) || walk_state->result_obj) {
     89		acpi_ut_remove_reference(return_desc);
     90		walk_state->result_obj = NULL;
     91	} else {
     92		/* Save the return value */
     93
     94		walk_state->result_obj = return_desc;
     95	}
     96
     97	return_ACPI_STATUS(status);
     98}
     99
    100/*******************************************************************************
    101 *
    102 * FUNCTION:    acpi_ex_opcode_1A_0T_0R
    103 *
    104 * PARAMETERS:  walk_state          - Current state (contains AML opcode)
    105 *
    106 * RETURN:      Status
    107 *
    108 * DESCRIPTION: Execute Type 1 monadic operator with numeric operand on
    109 *              object stack
    110 *
    111 ******************************************************************************/
    112
    113acpi_status acpi_ex_opcode_1A_0T_0R(struct acpi_walk_state *walk_state)
    114{
    115	union acpi_operand_object **operand = &walk_state->operands[0];
    116	acpi_status status = AE_OK;
    117
    118	ACPI_FUNCTION_TRACE_STR(ex_opcode_1A_0T_0R,
    119				acpi_ps_get_opcode_name(walk_state->opcode));
    120
    121	/* Examine the AML opcode */
    122
    123	switch (walk_state->opcode) {
    124	case AML_RELEASE_OP:	/*  Release (mutex_object) */
    125
    126		status = acpi_ex_release_mutex(operand[0], walk_state);
    127		break;
    128
    129	case AML_RESET_OP:	/*  Reset (event_object) */
    130
    131		status = acpi_ex_system_reset_event(operand[0]);
    132		break;
    133
    134	case AML_SIGNAL_OP:	/*  Signal (event_object) */
    135
    136		status = acpi_ex_system_signal_event(operand[0]);
    137		break;
    138
    139	case AML_SLEEP_OP:	/*  Sleep (msec_time) */
    140
    141		status = acpi_ex_system_do_sleep(operand[0]->integer.value);
    142		break;
    143
    144	case AML_STALL_OP:	/*  Stall (usec_time) */
    145
    146		status =
    147		    acpi_ex_system_do_stall((u32) operand[0]->integer.value);
    148		break;
    149
    150	case AML_UNLOAD_OP:	/*  Unload (Handle) */
    151
    152		status = acpi_ex_unload_table(operand[0]);
    153		break;
    154
    155	default:		/*  Unknown opcode  */
    156
    157		ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
    158			    walk_state->opcode));
    159		status = AE_AML_BAD_OPCODE;
    160		break;
    161	}
    162
    163	return_ACPI_STATUS(status);
    164}
    165
    166#ifdef _OBSOLETE_CODE		/* Was originally used for Load() operator */
    167/*******************************************************************************
    168 *
    169 * FUNCTION:    acpi_ex_opcode_1A_1T_0R
    170 *
    171 * PARAMETERS:  walk_state          - Current state (contains AML opcode)
    172 *
    173 * RETURN:      Status
    174 *
    175 * DESCRIPTION: Execute opcode with one argument, one target, and no
    176 *              return value.
    177 *
    178 ******************************************************************************/
    179
    180acpi_status acpi_ex_opcode_1A_1T_0R(struct acpi_walk_state *walk_state)
    181{
    182	acpi_status status = AE_OK;
    183	union acpi_operand_object **operand = &walk_state->operands[0];
    184
    185	ACPI_FUNCTION_TRACE_STR(ex_opcode_1A_1T_0R,
    186				acpi_ps_get_opcode_name(walk_state->opcode));
    187
    188	/* Examine the AML opcode */
    189
    190	switch (walk_state->opcode) {
    191#ifdef _OBSOLETE_CODE
    192	case AML_LOAD_OP:
    193
    194		status = acpi_ex_load_op(operand[0], operand[1], walk_state);
    195		break;
    196#endif
    197
    198	default:		/* Unknown opcode */
    199
    200		ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
    201			    walk_state->opcode));
    202		status = AE_AML_BAD_OPCODE;
    203		goto cleanup;
    204	}
    205
    206cleanup:
    207
    208	return_ACPI_STATUS(status);
    209}
    210#endif
    211
    212/*******************************************************************************
    213 *
    214 * FUNCTION:    acpi_ex_opcode_1A_1T_1R
    215 *
    216 * PARAMETERS:  walk_state          - Current state (contains AML opcode)
    217 *
    218 * RETURN:      Status
    219 *
    220 * DESCRIPTION: Execute opcode with one argument, one target, and a
    221 *              return value.
    222 *              January 2022: Added Load operator, with new ACPI 6.4
    223 *              semantics.
    224 *
    225 ******************************************************************************/
    226
    227acpi_status acpi_ex_opcode_1A_1T_1R(struct acpi_walk_state *walk_state)
    228{
    229	acpi_status status = AE_OK;
    230	union acpi_operand_object **operand = &walk_state->operands[0];
    231	union acpi_operand_object *return_desc = NULL;
    232	union acpi_operand_object *return_desc2 = NULL;
    233	u32 temp32;
    234	u32 i;
    235	u64 power_of_ten;
    236	u64 digit;
    237
    238	ACPI_FUNCTION_TRACE_STR(ex_opcode_1A_1T_1R,
    239				acpi_ps_get_opcode_name(walk_state->opcode));
    240
    241	/* Examine the AML opcode */
    242
    243	switch (walk_state->opcode) {
    244	case AML_BIT_NOT_OP:
    245	case AML_FIND_SET_LEFT_BIT_OP:
    246	case AML_FIND_SET_RIGHT_BIT_OP:
    247	case AML_FROM_BCD_OP:
    248	case AML_LOAD_OP:
    249	case AML_TO_BCD_OP:
    250	case AML_CONDITIONAL_REF_OF_OP:
    251
    252		/* Create a return object of type Integer for these opcodes */
    253
    254		return_desc = acpi_ut_create_internal_object(ACPI_TYPE_INTEGER);
    255		if (!return_desc) {
    256			status = AE_NO_MEMORY;
    257			goto cleanup;
    258		}
    259
    260		switch (walk_state->opcode) {
    261		case AML_BIT_NOT_OP:	/* Not (Operand, Result)  */
    262
    263			return_desc->integer.value = ~operand[0]->integer.value;
    264			break;
    265
    266		case AML_FIND_SET_LEFT_BIT_OP:	/* find_set_left_bit (Operand, Result) */
    267
    268			return_desc->integer.value = operand[0]->integer.value;
    269
    270			/*
    271			 * Acpi specification describes Integer type as a little
    272			 * endian unsigned value, so this boundary condition is valid.
    273			 */
    274			for (temp32 = 0; return_desc->integer.value &&
    275			     temp32 < ACPI_INTEGER_BIT_SIZE; ++temp32) {
    276				return_desc->integer.value >>= 1;
    277			}
    278
    279			return_desc->integer.value = temp32;
    280			break;
    281
    282		case AML_FIND_SET_RIGHT_BIT_OP:	/* find_set_right_bit (Operand, Result) */
    283
    284			return_desc->integer.value = operand[0]->integer.value;
    285
    286			/*
    287			 * The Acpi specification describes Integer type as a little
    288			 * endian unsigned value, so this boundary condition is valid.
    289			 */
    290			for (temp32 = 0; return_desc->integer.value &&
    291			     temp32 < ACPI_INTEGER_BIT_SIZE; ++temp32) {
    292				return_desc->integer.value <<= 1;
    293			}
    294
    295			/* Since the bit position is one-based, subtract from 33 (65) */
    296
    297			return_desc->integer.value =
    298			    temp32 ==
    299			    0 ? 0 : (ACPI_INTEGER_BIT_SIZE + 1) - temp32;
    300			break;
    301
    302		case AML_FROM_BCD_OP:	/* from_bcd (BCDValue, Result) */
    303			/*
    304			 * The 64-bit ACPI integer can hold 16 4-bit BCD characters
    305			 * (if table is 32-bit, integer can hold 8 BCD characters)
    306			 * Convert each 4-bit BCD value
    307			 */
    308			power_of_ten = 1;
    309			return_desc->integer.value = 0;
    310			digit = operand[0]->integer.value;
    311
    312			/* Convert each BCD digit (each is one nybble wide) */
    313
    314			for (i = 0;
    315			     (i < acpi_gbl_integer_nybble_width) && (digit > 0);
    316			     i++) {
    317
    318				/* Get the least significant 4-bit BCD digit */
    319
    320				temp32 = ((u32) digit) & 0xF;
    321
    322				/* Check the range of the digit */
    323
    324				if (temp32 > 9) {
    325					ACPI_ERROR((AE_INFO,
    326						    "BCD digit too large (not decimal): 0x%X",
    327						    temp32));
    328
    329					status = AE_AML_NUMERIC_OVERFLOW;
    330					goto cleanup;
    331				}
    332
    333				/* Sum the digit into the result with the current power of 10 */
    334
    335				return_desc->integer.value +=
    336				    (((u64) temp32) * power_of_ten);
    337
    338				/* Shift to next BCD digit */
    339
    340				digit >>= 4;
    341
    342				/* Next power of 10 */
    343
    344				power_of_ten *= 10;
    345			}
    346			break;
    347
    348		case AML_LOAD_OP:	/* Result1 = Load (Operand[0], Result1) */
    349
    350			return_desc->integer.value = 0;
    351			status =
    352			    acpi_ex_load_op(operand[0], return_desc,
    353					    walk_state);
    354			if (ACPI_SUCCESS(status)) {
    355
    356				/* Return -1 (non-zero) indicates success */
    357
    358				return_desc->integer.value = 0xFFFFFFFFFFFFFFFF;
    359			}
    360			break;
    361
    362		case AML_TO_BCD_OP:	/* to_bcd (Operand, Result) */
    363
    364			return_desc->integer.value = 0;
    365			digit = operand[0]->integer.value;
    366
    367			/* Each BCD digit is one nybble wide */
    368
    369			for (i = 0;
    370			     (i < acpi_gbl_integer_nybble_width) && (digit > 0);
    371			     i++) {
    372				(void)acpi_ut_short_divide(digit, 10, &digit,
    373							   &temp32);
    374
    375				/*
    376				 * Insert the BCD digit that resides in the
    377				 * remainder from above
    378				 */
    379				return_desc->integer.value |=
    380				    (((u64) temp32) << ACPI_MUL_4(i));
    381			}
    382
    383			/* Overflow if there is any data left in Digit */
    384
    385			if (digit > 0) {
    386				ACPI_ERROR((AE_INFO,
    387					    "Integer too large to convert to BCD: 0x%8.8X%8.8X",
    388					    ACPI_FORMAT_UINT64(operand[0]->
    389							       integer.value)));
    390				status = AE_AML_NUMERIC_OVERFLOW;
    391				goto cleanup;
    392			}
    393			break;
    394
    395		case AML_CONDITIONAL_REF_OF_OP:	/* cond_ref_of (source_object, Result) */
    396			/*
    397			 * This op is a little strange because the internal return value is
    398			 * different than the return value stored in the result descriptor
    399			 * (There are really two return values)
    400			 */
    401			if ((struct acpi_namespace_node *)operand[0] ==
    402			    acpi_gbl_root_node) {
    403				/*
    404				 * This means that the object does not exist in the namespace,
    405				 * return FALSE
    406				 */
    407				return_desc->integer.value = 0;
    408				goto cleanup;
    409			}
    410
    411			/* Get the object reference, store it, and remove our reference */
    412
    413			status = acpi_ex_get_object_reference(operand[0],
    414							      &return_desc2,
    415							      walk_state);
    416			if (ACPI_FAILURE(status)) {
    417				goto cleanup;
    418			}
    419
    420			status =
    421			    acpi_ex_store(return_desc2, operand[1], walk_state);
    422			acpi_ut_remove_reference(return_desc2);
    423
    424			/* The object exists in the namespace, return TRUE */
    425
    426			return_desc->integer.value = ACPI_UINT64_MAX;
    427			goto cleanup;
    428
    429		default:
    430
    431			/* No other opcodes get here */
    432
    433			break;
    434		}
    435		break;
    436
    437	case AML_STORE_OP:	/* Store (Source, Target) */
    438		/*
    439		 * A store operand is typically a number, string, buffer or lvalue
    440		 * Be careful about deleting the source object,
    441		 * since the object itself may have been stored.
    442		 */
    443		status = acpi_ex_store(operand[0], operand[1], walk_state);
    444		if (ACPI_FAILURE(status)) {
    445			return_ACPI_STATUS(status);
    446		}
    447
    448		/* It is possible that the Store already produced a return object */
    449
    450		if (!walk_state->result_obj) {
    451			/*
    452			 * Normally, we would remove a reference on the Operand[0]
    453			 * parameter; But since it is being used as the internal return
    454			 * object (meaning we would normally increment it), the two
    455			 * cancel out, and we simply don't do anything.
    456			 */
    457			walk_state->result_obj = operand[0];
    458			walk_state->operands[0] = NULL;	/* Prevent deletion */
    459		}
    460		return_ACPI_STATUS(status);
    461
    462		/*
    463		 * ACPI 2.0 Opcodes
    464		 */
    465	case AML_COPY_OBJECT_OP:	/* copy_object (Source, Target) */
    466
    467		status =
    468		    acpi_ut_copy_iobject_to_iobject(operand[0], &return_desc,
    469						    walk_state);
    470		break;
    471
    472	case AML_TO_DECIMAL_STRING_OP:	/* to_decimal_string (Data, Result) */
    473
    474		status =
    475		    acpi_ex_convert_to_string(operand[0], &return_desc,
    476					      ACPI_EXPLICIT_CONVERT_DECIMAL);
    477		if (return_desc == operand[0]) {
    478
    479			/* No conversion performed, add ref to handle return value */
    480
    481			acpi_ut_add_reference(return_desc);
    482		}
    483		break;
    484
    485	case AML_TO_HEX_STRING_OP:	/* to_hex_string (Data, Result) */
    486
    487		status =
    488		    acpi_ex_convert_to_string(operand[0], &return_desc,
    489					      ACPI_EXPLICIT_CONVERT_HEX);
    490		if (return_desc == operand[0]) {
    491
    492			/* No conversion performed, add ref to handle return value */
    493
    494			acpi_ut_add_reference(return_desc);
    495		}
    496		break;
    497
    498	case AML_TO_BUFFER_OP:	/* to_buffer (Data, Result) */
    499
    500		status = acpi_ex_convert_to_buffer(operand[0], &return_desc);
    501		if (return_desc == operand[0]) {
    502
    503			/* No conversion performed, add ref to handle return value */
    504
    505			acpi_ut_add_reference(return_desc);
    506		}
    507		break;
    508
    509	case AML_TO_INTEGER_OP:	/* to_integer (Data, Result) */
    510
    511		/* Perform "explicit" conversion */
    512
    513		status =
    514		    acpi_ex_convert_to_integer(operand[0], &return_desc, 0);
    515		if (return_desc == operand[0]) {
    516
    517			/* No conversion performed, add ref to handle return value */
    518
    519			acpi_ut_add_reference(return_desc);
    520		}
    521		break;
    522
    523	case AML_SHIFT_LEFT_BIT_OP:	/* shift_left_bit (Source, bit_num) */
    524	case AML_SHIFT_RIGHT_BIT_OP:	/* shift_right_bit (Source, bit_num) */
    525
    526		/* These are two obsolete opcodes */
    527
    528		ACPI_ERROR((AE_INFO,
    529			    "%s is obsolete and not implemented",
    530			    acpi_ps_get_opcode_name(walk_state->opcode)));
    531		status = AE_SUPPORT;
    532		goto cleanup;
    533
    534	default:		/* Unknown opcode */
    535
    536		ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
    537			    walk_state->opcode));
    538		status = AE_AML_BAD_OPCODE;
    539		goto cleanup;
    540	}
    541
    542	if (ACPI_SUCCESS(status)) {
    543
    544		/* Store the return value computed above into the target object */
    545
    546		status = acpi_ex_store(return_desc, operand[1], walk_state);
    547	}
    548
    549cleanup:
    550
    551	/* Delete return object on error */
    552
    553	if (ACPI_FAILURE(status)) {
    554		acpi_ut_remove_reference(return_desc);
    555	}
    556
    557	/* Save return object on success */
    558
    559	else if (!walk_state->result_obj) {
    560		walk_state->result_obj = return_desc;
    561	}
    562
    563	return_ACPI_STATUS(status);
    564}
    565
    566/*******************************************************************************
    567 *
    568 * FUNCTION:    acpi_ex_opcode_1A_0T_1R
    569 *
    570 * PARAMETERS:  walk_state          - Current state (contains AML opcode)
    571 *
    572 * RETURN:      Status
    573 *
    574 * DESCRIPTION: Execute opcode with one argument, no target, and a return value
    575 *
    576 ******************************************************************************/
    577
    578acpi_status acpi_ex_opcode_1A_0T_1R(struct acpi_walk_state *walk_state)
    579{
    580	union acpi_operand_object **operand = &walk_state->operands[0];
    581	union acpi_operand_object *temp_desc;
    582	union acpi_operand_object *return_desc = NULL;
    583	acpi_status status = AE_OK;
    584	u32 type;
    585	u64 value;
    586
    587	ACPI_FUNCTION_TRACE_STR(ex_opcode_1A_0T_1R,
    588				acpi_ps_get_opcode_name(walk_state->opcode));
    589
    590	/* Examine the AML opcode */
    591
    592	switch (walk_state->opcode) {
    593	case AML_LOGICAL_NOT_OP:	/* LNot (Operand) */
    594
    595		return_desc = acpi_ut_create_integer_object((u64) 0);
    596		if (!return_desc) {
    597			status = AE_NO_MEMORY;
    598			goto cleanup;
    599		}
    600
    601		/*
    602		 * Set result to ONES (TRUE) if Value == 0. Note:
    603		 * return_desc->Integer.Value is initially == 0 (FALSE) from above.
    604		 */
    605		if (!operand[0]->integer.value) {
    606			return_desc->integer.value = ACPI_UINT64_MAX;
    607		}
    608		break;
    609
    610	case AML_DECREMENT_OP:	/* Decrement (Operand)  */
    611	case AML_INCREMENT_OP:	/* Increment (Operand)  */
    612		/*
    613		 * Create a new integer. Can't just get the base integer and
    614		 * increment it because it may be an Arg or Field.
    615		 */
    616		return_desc = acpi_ut_create_internal_object(ACPI_TYPE_INTEGER);
    617		if (!return_desc) {
    618			status = AE_NO_MEMORY;
    619			goto cleanup;
    620		}
    621
    622		/*
    623		 * Since we are expecting a Reference operand, it can be either a
    624		 * NS Node or an internal object.
    625		 */
    626		temp_desc = operand[0];
    627		if (ACPI_GET_DESCRIPTOR_TYPE(temp_desc) ==
    628		    ACPI_DESC_TYPE_OPERAND) {
    629
    630			/* Internal reference object - prevent deletion */
    631
    632			acpi_ut_add_reference(temp_desc);
    633		}
    634
    635		/*
    636		 * Convert the Reference operand to an Integer (This removes a
    637		 * reference on the Operand[0] object)
    638		 *
    639		 * NOTE:  We use LNOT_OP here in order to force resolution of the
    640		 * reference operand to an actual integer.
    641		 */
    642		status = acpi_ex_resolve_operands(AML_LOGICAL_NOT_OP,
    643						  &temp_desc, walk_state);
    644		if (ACPI_FAILURE(status)) {
    645			ACPI_EXCEPTION((AE_INFO, status,
    646					"While resolving operands for [%s]",
    647					acpi_ps_get_opcode_name(walk_state->
    648								opcode)));
    649
    650			goto cleanup;
    651		}
    652
    653		/*
    654		 * temp_desc is now guaranteed to be an Integer object --
    655		 * Perform the actual increment or decrement
    656		 */
    657		if (walk_state->opcode == AML_INCREMENT_OP) {
    658			return_desc->integer.value =
    659			    temp_desc->integer.value + 1;
    660		} else {
    661			return_desc->integer.value =
    662			    temp_desc->integer.value - 1;
    663		}
    664
    665		/* Finished with this Integer object */
    666
    667		acpi_ut_remove_reference(temp_desc);
    668
    669		/*
    670		 * Store the result back (indirectly) through the original
    671		 * Reference object
    672		 */
    673		status = acpi_ex_store(return_desc, operand[0], walk_state);
    674		break;
    675
    676	case AML_OBJECT_TYPE_OP:	/* object_type (source_object) */
    677		/*
    678		 * Note: The operand is not resolved at this point because we want to
    679		 * get the associated object, not its value. For example, we don't
    680		 * want to resolve a field_unit to its value, we want the actual
    681		 * field_unit object.
    682		 */
    683
    684		/* Get the type of the base object */
    685
    686		status =
    687		    acpi_ex_resolve_multiple(walk_state, operand[0], &type,
    688					     NULL);
    689		if (ACPI_FAILURE(status)) {
    690			goto cleanup;
    691		}
    692
    693		/* Allocate a descriptor to hold the type. */
    694
    695		return_desc = acpi_ut_create_integer_object((u64) type);
    696		if (!return_desc) {
    697			status = AE_NO_MEMORY;
    698			goto cleanup;
    699		}
    700		break;
    701
    702	case AML_SIZE_OF_OP:	/* size_of (source_object) */
    703		/*
    704		 * Note: The operand is not resolved at this point because we want to
    705		 * get the associated object, not its value.
    706		 */
    707
    708		/* Get the base object */
    709
    710		status =
    711		    acpi_ex_resolve_multiple(walk_state, operand[0], &type,
    712					     &temp_desc);
    713		if (ACPI_FAILURE(status)) {
    714			goto cleanup;
    715		}
    716
    717		/*
    718		 * The type of the base object must be integer, buffer, string, or
    719		 * package. All others are not supported.
    720		 *
    721		 * NOTE: Integer is not specifically supported by the ACPI spec,
    722		 * but is supported implicitly via implicit operand conversion.
    723		 * rather than bother with conversion, we just use the byte width
    724		 * global (4 or 8 bytes).
    725		 */
    726		switch (type) {
    727		case ACPI_TYPE_INTEGER:
    728
    729			value = acpi_gbl_integer_byte_width;
    730			break;
    731
    732		case ACPI_TYPE_STRING:
    733
    734			value = temp_desc->string.length;
    735			break;
    736
    737		case ACPI_TYPE_BUFFER:
    738
    739			/* Buffer arguments may not be evaluated at this point */
    740
    741			status = acpi_ds_get_buffer_arguments(temp_desc);
    742			value = temp_desc->buffer.length;
    743			break;
    744
    745		case ACPI_TYPE_PACKAGE:
    746
    747			/* Package arguments may not be evaluated at this point */
    748
    749			status = acpi_ds_get_package_arguments(temp_desc);
    750			value = temp_desc->package.count;
    751			break;
    752
    753		default:
    754
    755			ACPI_ERROR((AE_INFO,
    756				    "Operand must be Buffer/Integer/String/Package"
    757				    " - found type %s",
    758				    acpi_ut_get_type_name(type)));
    759
    760			status = AE_AML_OPERAND_TYPE;
    761			goto cleanup;
    762		}
    763
    764		if (ACPI_FAILURE(status)) {
    765			goto cleanup;
    766		}
    767
    768		/*
    769		 * Now that we have the size of the object, create a result
    770		 * object to hold the value
    771		 */
    772		return_desc = acpi_ut_create_integer_object(value);
    773		if (!return_desc) {
    774			status = AE_NO_MEMORY;
    775			goto cleanup;
    776		}
    777		break;
    778
    779	case AML_REF_OF_OP:	/* ref_of (source_object) */
    780
    781		status =
    782		    acpi_ex_get_object_reference(operand[0], &return_desc,
    783						 walk_state);
    784		if (ACPI_FAILURE(status)) {
    785			goto cleanup;
    786		}
    787		break;
    788
    789	case AML_DEREF_OF_OP:	/* deref_of (obj_reference | String) */
    790
    791		/* Check for a method local or argument, or standalone String */
    792
    793		if (ACPI_GET_DESCRIPTOR_TYPE(operand[0]) ==
    794		    ACPI_DESC_TYPE_NAMED) {
    795			temp_desc =
    796			    acpi_ns_get_attached_object((struct
    797							 acpi_namespace_node *)
    798							operand[0]);
    799			if (temp_desc
    800			    && ((temp_desc->common.type == ACPI_TYPE_STRING)
    801				|| (temp_desc->common.type ==
    802				    ACPI_TYPE_LOCAL_REFERENCE))) {
    803				operand[0] = temp_desc;
    804				acpi_ut_add_reference(temp_desc);
    805			} else {
    806				status = AE_AML_OPERAND_TYPE;
    807				goto cleanup;
    808			}
    809		} else {
    810			switch ((operand[0])->common.type) {
    811			case ACPI_TYPE_LOCAL_REFERENCE:
    812				/*
    813				 * This is a deref_of (local_x | arg_x)
    814				 *
    815				 * Must resolve/dereference the local/arg reference first
    816				 */
    817				switch (operand[0]->reference.class) {
    818				case ACPI_REFCLASS_LOCAL:
    819				case ACPI_REFCLASS_ARG:
    820
    821					/* Set Operand[0] to the value of the local/arg */
    822
    823					status =
    824					    acpi_ds_method_data_get_value
    825					    (operand[0]->reference.class,
    826					     operand[0]->reference.value,
    827					     walk_state, &temp_desc);
    828					if (ACPI_FAILURE(status)) {
    829						goto cleanup;
    830					}
    831
    832					/*
    833					 * Delete our reference to the input object and
    834					 * point to the object just retrieved
    835					 */
    836					acpi_ut_remove_reference(operand[0]);
    837					operand[0] = temp_desc;
    838					break;
    839
    840				case ACPI_REFCLASS_REFOF:
    841
    842					/* Get the object to which the reference refers */
    843
    844					temp_desc =
    845					    operand[0]->reference.object;
    846					acpi_ut_remove_reference(operand[0]);
    847					operand[0] = temp_desc;
    848					break;
    849
    850				default:
    851
    852					/* Must be an Index op - handled below */
    853					break;
    854				}
    855				break;
    856
    857			case ACPI_TYPE_STRING:
    858
    859				break;
    860
    861			default:
    862
    863				status = AE_AML_OPERAND_TYPE;
    864				goto cleanup;
    865			}
    866		}
    867
    868		if (ACPI_GET_DESCRIPTOR_TYPE(operand[0]) !=
    869		    ACPI_DESC_TYPE_NAMED) {
    870			if ((operand[0])->common.type == ACPI_TYPE_STRING) {
    871				/*
    872				 * This is a deref_of (String). The string is a reference
    873				 * to a named ACPI object.
    874				 *
    875				 * 1) Find the owning Node
    876				 * 2) Dereference the node to an actual object. Could be a
    877				 *    Field, so we need to resolve the node to a value.
    878				 */
    879				status =
    880				    acpi_ns_get_node_unlocked(walk_state->
    881							      scope_info->scope.
    882							      node,
    883							      operand[0]->
    884							      string.pointer,
    885							      ACPI_NS_SEARCH_PARENT,
    886							      ACPI_CAST_INDIRECT_PTR
    887							      (struct
    888							       acpi_namespace_node,
    889							       &return_desc));
    890				if (ACPI_FAILURE(status)) {
    891					goto cleanup;
    892				}
    893
    894				status =
    895				    acpi_ex_resolve_node_to_value
    896				    (ACPI_CAST_INDIRECT_PTR
    897				     (struct acpi_namespace_node, &return_desc),
    898				     walk_state);
    899				goto cleanup;
    900			}
    901		}
    902
    903		/* Operand[0] may have changed from the code above */
    904
    905		if (ACPI_GET_DESCRIPTOR_TYPE(operand[0]) ==
    906		    ACPI_DESC_TYPE_NAMED) {
    907			/*
    908			 * This is a deref_of (object_reference)
    909			 * Get the actual object from the Node (This is the dereference).
    910			 * This case may only happen when a local_x or arg_x is
    911			 * dereferenced above, or for references to device and
    912			 * thermal objects.
    913			 */
    914			switch (((struct acpi_namespace_node *)operand[0])->
    915				type) {
    916			case ACPI_TYPE_DEVICE:
    917			case ACPI_TYPE_THERMAL:
    918
    919				/* These types have no node subobject, return the NS node */
    920
    921				return_desc = operand[0];
    922				break;
    923
    924			default:
    925				/* For most types, get the object attached to the node */
    926
    927				return_desc = acpi_ns_get_attached_object((struct acpi_namespace_node *)operand[0]);
    928				acpi_ut_add_reference(return_desc);
    929				break;
    930			}
    931		} else {
    932			/*
    933			 * This must be a reference object produced by either the
    934			 * Index() or ref_of() operator
    935			 */
    936			switch (operand[0]->reference.class) {
    937			case ACPI_REFCLASS_INDEX:
    938				/*
    939				 * The target type for the Index operator must be
    940				 * either a Buffer or a Package
    941				 */
    942				switch (operand[0]->reference.target_type) {
    943				case ACPI_TYPE_BUFFER_FIELD:
    944
    945					temp_desc =
    946					    operand[0]->reference.object;
    947
    948					/*
    949					 * Create a new object that contains one element of the
    950					 * buffer -- the element pointed to by the index.
    951					 *
    952					 * NOTE: index into a buffer is NOT a pointer to a
    953					 * sub-buffer of the main buffer, it is only a pointer to a
    954					 * single element (byte) of the buffer!
    955					 *
    956					 * Since we are returning the value of the buffer at the
    957					 * indexed location, we don't need to add an additional
    958					 * reference to the buffer itself.
    959					 */
    960					return_desc =
    961					    acpi_ut_create_integer_object((u64)
    962									  temp_desc->buffer.pointer[operand[0]->reference.value]);
    963					if (!return_desc) {
    964						status = AE_NO_MEMORY;
    965						goto cleanup;
    966					}
    967					break;
    968
    969				case ACPI_TYPE_PACKAGE:
    970					/*
    971					 * Return the referenced element of the package. We must
    972					 * add another reference to the referenced object, however.
    973					 */
    974					return_desc =
    975					    *(operand[0]->reference.where);
    976					if (!return_desc) {
    977						/*
    978						 * Element is NULL, do not allow the dereference.
    979						 * This provides compatibility with other ACPI
    980						 * implementations.
    981						 */
    982						return_ACPI_STATUS
    983						    (AE_AML_UNINITIALIZED_ELEMENT);
    984					}
    985
    986					acpi_ut_add_reference(return_desc);
    987					break;
    988
    989				default:
    990
    991					ACPI_ERROR((AE_INFO,
    992						    "Unknown Index TargetType 0x%X in reference object %p",
    993						    operand[0]->reference.
    994						    target_type, operand[0]));
    995
    996					status = AE_AML_OPERAND_TYPE;
    997					goto cleanup;
    998				}
    999				break;
   1000
   1001			case ACPI_REFCLASS_REFOF:
   1002
   1003				return_desc = operand[0]->reference.object;
   1004
   1005				if (ACPI_GET_DESCRIPTOR_TYPE(return_desc) ==
   1006				    ACPI_DESC_TYPE_NAMED) {
   1007					return_desc =
   1008					    acpi_ns_get_attached_object((struct
   1009									 acpi_namespace_node
   1010									 *)
   1011									return_desc);
   1012					if (!return_desc) {
   1013						break;
   1014					}
   1015
   1016					/*
   1017					 * June 2013:
   1018					 * buffer_fields/field_units require additional resolution
   1019					 */
   1020					switch (return_desc->common.type) {
   1021					case ACPI_TYPE_BUFFER_FIELD:
   1022					case ACPI_TYPE_LOCAL_REGION_FIELD:
   1023					case ACPI_TYPE_LOCAL_BANK_FIELD:
   1024					case ACPI_TYPE_LOCAL_INDEX_FIELD:
   1025
   1026						status =
   1027						    acpi_ex_read_data_from_field
   1028						    (walk_state, return_desc,
   1029						     &temp_desc);
   1030						if (ACPI_FAILURE(status)) {
   1031							return_ACPI_STATUS
   1032							    (status);
   1033						}
   1034
   1035						return_desc = temp_desc;
   1036						break;
   1037
   1038					default:
   1039
   1040						/* Add another reference to the object */
   1041
   1042						acpi_ut_add_reference
   1043						    (return_desc);
   1044						break;
   1045					}
   1046				}
   1047				break;
   1048
   1049			default:
   1050
   1051				ACPI_ERROR((AE_INFO,
   1052					    "Unknown class in reference(%p) - 0x%2.2X",
   1053					    operand[0],
   1054					    operand[0]->reference.class));
   1055
   1056				status = AE_TYPE;
   1057				goto cleanup;
   1058			}
   1059		}
   1060		break;
   1061
   1062	default:
   1063
   1064		ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
   1065			    walk_state->opcode));
   1066
   1067		status = AE_AML_BAD_OPCODE;
   1068		goto cleanup;
   1069	}
   1070
   1071cleanup:
   1072
   1073	/* Delete return object on error */
   1074
   1075	if (ACPI_FAILURE(status)) {
   1076		acpi_ut_remove_reference(return_desc);
   1077	}
   1078
   1079	/* Save return object on success */
   1080
   1081	else {
   1082		walk_state->result_obj = return_desc;
   1083	}
   1084
   1085	return_ACPI_STATUS(status);
   1086}