2 /******************************************************************************
4 * Module Name: exoparg1 - AML execution - opcodes with 1 argument
6 *****************************************************************************/
9 * Copyright (C) 2000 - 2006, R. Byron Moore
10 * All rights reserved.
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
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.
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.
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.
45 #include <acpi/acpi.h>
46 #include <acpi/acparser.h>
47 #include <acpi/acdispat.h>
48 #include <acpi/acinterp.h>
49 #include <acpi/amlcode.h>
50 #include <acpi/acnamesp.h>
52 #define _COMPONENT ACPI_EXECUTER
53 ACPI_MODULE_NAME("exoparg1")
56 * Naming convention for AML interpreter execution routines.
58 * The routines that begin execution of AML opcodes are named with a common
59 * convention based upon the number of arguments, the number of target operands,
60 * and whether or not a value is returned:
62 * AcpiExOpcode_xA_yT_zR
66 * xA - ARGUMENTS: The number of arguments (input operands) that are
67 * required for this opcode type (0 through 6 args).
68 * yT - TARGETS: The number of targets (output operands) that are required
69 * for this opcode type (0, 1, or 2 targets).
70 * zR - RETURN VALUE: Indicates whether this opcode type returns a value
71 * as the function return (0 or 1).
73 * The AcpiExOpcode* functions are called via the Dispatcher component with
74 * fully resolved operands.
76 /*******************************************************************************
78 * FUNCTION: acpi_ex_opcode_0A_0T_1R
80 * PARAMETERS: walk_state - Current state (contains AML opcode)
84 * DESCRIPTION: Execute operator with no operands, one return value
86 ******************************************************************************/
87 acpi_status
acpi_ex_opcode_0A_0T_1R(struct acpi_walk_state
*walk_state
)
89 acpi_status status
= AE_OK
;
90 union acpi_operand_object
*return_desc
= NULL
;
92 ACPI_FUNCTION_TRACE_STR("ex_opcode_0A_0T_1R",
93 acpi_ps_get_opcode_name(walk_state
->opcode
));
95 /* Examine the AML opcode */
97 switch (walk_state
->opcode
) {
98 case AML_TIMER_OP
: /* Timer () */
100 /* Create a return object of type Integer */
102 return_desc
= acpi_ut_create_internal_object(ACPI_TYPE_INTEGER
);
104 status
= AE_NO_MEMORY
;
107 #if ACPI_MACHINE_WIDTH != 16
108 return_desc
->integer
.value
= acpi_os_get_timer();
112 default: /* Unknown opcode */
114 ACPI_ERROR((AE_INFO
, "Unknown AML opcode %X",
115 walk_state
->opcode
));
116 status
= AE_AML_BAD_OPCODE
;
122 /* Delete return object on error */
124 if ((ACPI_FAILURE(status
)) || walk_state
->result_obj
) {
125 acpi_ut_remove_reference(return_desc
);
127 /* Save the return value */
129 walk_state
->result_obj
= return_desc
;
132 return_ACPI_STATUS(status
);
135 /*******************************************************************************
137 * FUNCTION: acpi_ex_opcode_1A_0T_0R
139 * PARAMETERS: walk_state - Current state (contains AML opcode)
143 * DESCRIPTION: Execute Type 1 monadic operator with numeric operand on
146 ******************************************************************************/
148 acpi_status
acpi_ex_opcode_1A_0T_0R(struct acpi_walk_state
*walk_state
)
150 union acpi_operand_object
**operand
= &walk_state
->operands
[0];
151 acpi_status status
= AE_OK
;
153 ACPI_FUNCTION_TRACE_STR("ex_opcode_1A_0T_0R",
154 acpi_ps_get_opcode_name(walk_state
->opcode
));
156 /* Examine the AML opcode */
158 switch (walk_state
->opcode
) {
159 case AML_RELEASE_OP
: /* Release (mutex_object) */
161 status
= acpi_ex_release_mutex(operand
[0], walk_state
);
164 case AML_RESET_OP
: /* Reset (event_object) */
166 status
= acpi_ex_system_reset_event(operand
[0]);
169 case AML_SIGNAL_OP
: /* Signal (event_object) */
171 status
= acpi_ex_system_signal_event(operand
[0]);
174 case AML_SLEEP_OP
: /* Sleep (msec_time) */
176 status
= acpi_ex_system_do_suspend(operand
[0]->integer
.value
);
179 case AML_STALL_OP
: /* Stall (usec_time) */
182 acpi_ex_system_do_stall((u32
) operand
[0]->integer
.value
);
185 case AML_UNLOAD_OP
: /* Unload (Handle) */
187 status
= acpi_ex_unload_table(operand
[0]);
190 default: /* Unknown opcode */
192 ACPI_ERROR((AE_INFO
, "Unknown AML opcode %X",
193 walk_state
->opcode
));
194 status
= AE_AML_BAD_OPCODE
;
198 return_ACPI_STATUS(status
);
201 /*******************************************************************************
203 * FUNCTION: acpi_ex_opcode_1A_1T_0R
205 * PARAMETERS: walk_state - Current state (contains AML opcode)
209 * DESCRIPTION: Execute opcode with one argument, one target, and no
212 ******************************************************************************/
214 acpi_status
acpi_ex_opcode_1A_1T_0R(struct acpi_walk_state
*walk_state
)
216 acpi_status status
= AE_OK
;
217 union acpi_operand_object
**operand
= &walk_state
->operands
[0];
219 ACPI_FUNCTION_TRACE_STR("ex_opcode_1A_1T_0R",
220 acpi_ps_get_opcode_name(walk_state
->opcode
));
222 /* Examine the AML opcode */
224 switch (walk_state
->opcode
) {
227 status
= acpi_ex_load_op(operand
[0], operand
[1], walk_state
);
230 default: /* Unknown opcode */
232 ACPI_ERROR((AE_INFO
, "Unknown AML opcode %X",
233 walk_state
->opcode
));
234 status
= AE_AML_BAD_OPCODE
;
240 return_ACPI_STATUS(status
);
243 /*******************************************************************************
245 * FUNCTION: acpi_ex_opcode_1A_1T_1R
247 * PARAMETERS: walk_state - Current state (contains AML opcode)
251 * DESCRIPTION: Execute opcode with one argument, one target, and a
254 ******************************************************************************/
256 acpi_status
acpi_ex_opcode_1A_1T_1R(struct acpi_walk_state
*walk_state
)
258 acpi_status status
= AE_OK
;
259 union acpi_operand_object
**operand
= &walk_state
->operands
[0];
260 union acpi_operand_object
*return_desc
= NULL
;
261 union acpi_operand_object
*return_desc2
= NULL
;
264 acpi_integer power_of_ten
;
267 ACPI_FUNCTION_TRACE_STR("ex_opcode_1A_1T_1R",
268 acpi_ps_get_opcode_name(walk_state
->opcode
));
270 /* Examine the AML opcode */
272 switch (walk_state
->opcode
) {
274 case AML_FIND_SET_LEFT_BIT_OP
:
275 case AML_FIND_SET_RIGHT_BIT_OP
:
276 case AML_FROM_BCD_OP
:
278 case AML_COND_REF_OF_OP
:
280 /* Create a return object of type Integer for these opcodes */
282 return_desc
= acpi_ut_create_internal_object(ACPI_TYPE_INTEGER
);
284 status
= AE_NO_MEMORY
;
288 switch (walk_state
->opcode
) {
289 case AML_BIT_NOT_OP
: /* Not (Operand, Result) */
291 return_desc
->integer
.value
= ~operand
[0]->integer
.value
;
294 case AML_FIND_SET_LEFT_BIT_OP
: /* find_set_left_bit (Operand, Result) */
296 return_desc
->integer
.value
= operand
[0]->integer
.value
;
299 * Acpi specification describes Integer type as a little
300 * endian unsigned value, so this boundary condition is valid.
302 for (temp32
= 0; return_desc
->integer
.value
&&
303 temp32
< ACPI_INTEGER_BIT_SIZE
; ++temp32
) {
304 return_desc
->integer
.value
>>= 1;
307 return_desc
->integer
.value
= temp32
;
310 case AML_FIND_SET_RIGHT_BIT_OP
: /* find_set_right_bit (Operand, Result) */
312 return_desc
->integer
.value
= operand
[0]->integer
.value
;
315 * The Acpi specification describes Integer type as a little
316 * endian unsigned value, so this boundary condition is valid.
318 for (temp32
= 0; return_desc
->integer
.value
&&
319 temp32
< ACPI_INTEGER_BIT_SIZE
; ++temp32
) {
320 return_desc
->integer
.value
<<= 1;
323 /* Since the bit position is one-based, subtract from 33 (65) */
325 return_desc
->integer
.value
= temp32
== 0 ? 0 :
326 (ACPI_INTEGER_BIT_SIZE
+ 1) - temp32
;
329 case AML_FROM_BCD_OP
: /* from_bcd (BCDValue, Result) */
332 * The 64-bit ACPI integer can hold 16 4-bit BCD characters
333 * (if table is 32-bit, integer can hold 8 BCD characters)
334 * Convert each 4-bit BCD value
337 return_desc
->integer
.value
= 0;
338 digit
= operand
[0]->integer
.value
;
340 /* Convert each BCD digit (each is one nybble wide) */
343 (i
< acpi_gbl_integer_nybble_width
) && (digit
> 0);
345 /* Get the least significant 4-bit BCD digit */
347 temp32
= ((u32
) digit
) & 0xF;
349 /* Check the range of the digit */
353 "BCD digit too large (not decimal): 0x%X",
356 status
= AE_AML_NUMERIC_OVERFLOW
;
360 /* Sum the digit into the result with the current power of 10 */
362 return_desc
->integer
.value
+=
363 (((acpi_integer
) temp32
) * power_of_ten
);
365 /* Shift to next BCD digit */
369 /* Next power of 10 */
375 case AML_TO_BCD_OP
: /* to_bcd (Operand, Result) */
377 return_desc
->integer
.value
= 0;
378 digit
= operand
[0]->integer
.value
;
380 /* Each BCD digit is one nybble wide */
383 (i
< acpi_gbl_integer_nybble_width
) && (digit
> 0);
385 (void)acpi_ut_short_divide(digit
, 10, &digit
,
389 * Insert the BCD digit that resides in the
390 * remainder from above
392 return_desc
->integer
.value
|=
393 (((acpi_integer
) temp32
) << ACPI_MUL_4(i
));
396 /* Overflow if there is any data left in Digit */
400 "Integer too large to convert to BCD: %8.8X%8.8X",
401 ACPI_FORMAT_UINT64(operand
[0]->
403 status
= AE_AML_NUMERIC_OVERFLOW
;
408 case AML_COND_REF_OF_OP
: /* cond_ref_of (source_object, Result) */
411 * This op is a little strange because the internal return value is
412 * different than the return value stored in the result descriptor
413 * (There are really two return values)
415 if ((struct acpi_namespace_node
*)operand
[0] ==
416 acpi_gbl_root_node
) {
418 * This means that the object does not exist in the namespace,
421 return_desc
->integer
.value
= 0;
425 /* Get the object reference, store it, and remove our reference */
427 status
= acpi_ex_get_object_reference(operand
[0],
430 if (ACPI_FAILURE(status
)) {
435 acpi_ex_store(return_desc2
, operand
[1], walk_state
);
436 acpi_ut_remove_reference(return_desc2
);
438 /* The object exists in the namespace, return TRUE */
440 return_desc
->integer
.value
= ACPI_INTEGER_MAX
;
444 /* No other opcodes get here */
449 case AML_STORE_OP
: /* Store (Source, Target) */
452 * A store operand is typically a number, string, buffer or lvalue
453 * Be careful about deleting the source object,
454 * since the object itself may have been stored.
456 status
= acpi_ex_store(operand
[0], operand
[1], walk_state
);
457 if (ACPI_FAILURE(status
)) {
458 return_ACPI_STATUS(status
);
461 /* It is possible that the Store already produced a return object */
463 if (!walk_state
->result_obj
) {
465 * Normally, we would remove a reference on the Operand[0]
466 * parameter; But since it is being used as the internal return
467 * object (meaning we would normally increment it), the two
468 * cancel out, and we simply don't do anything.
470 walk_state
->result_obj
= operand
[0];
471 walk_state
->operands
[0] = NULL
; /* Prevent deletion */
473 return_ACPI_STATUS(status
);
478 case AML_COPY_OP
: /* Copy (Source, Target) */
481 acpi_ut_copy_iobject_to_iobject(operand
[0], &return_desc
,
485 case AML_TO_DECSTRING_OP
: /* to_decimal_string (Data, Result) */
487 status
= acpi_ex_convert_to_string(operand
[0], &return_desc
,
488 ACPI_EXPLICIT_CONVERT_DECIMAL
);
489 if (return_desc
== operand
[0]) {
490 /* No conversion performed, add ref to handle return value */
491 acpi_ut_add_reference(return_desc
);
495 case AML_TO_HEXSTRING_OP
: /* to_hex_string (Data, Result) */
497 status
= acpi_ex_convert_to_string(operand
[0], &return_desc
,
498 ACPI_EXPLICIT_CONVERT_HEX
);
499 if (return_desc
== operand
[0]) {
500 /* No conversion performed, add ref to handle return value */
501 acpi_ut_add_reference(return_desc
);
505 case AML_TO_BUFFER_OP
: /* to_buffer (Data, Result) */
507 status
= acpi_ex_convert_to_buffer(operand
[0], &return_desc
);
508 if (return_desc
== operand
[0]) {
509 /* No conversion performed, add ref to handle return value */
510 acpi_ut_add_reference(return_desc
);
514 case AML_TO_INTEGER_OP
: /* to_integer (Data, Result) */
516 status
= acpi_ex_convert_to_integer(operand
[0], &return_desc
,
518 if (return_desc
== operand
[0]) {
519 /* No conversion performed, add ref to handle return value */
520 acpi_ut_add_reference(return_desc
);
524 case AML_SHIFT_LEFT_BIT_OP
: /* shift_left_bit (Source, bit_num) */
525 case AML_SHIFT_RIGHT_BIT_OP
: /* shift_right_bit (Source, bit_num) */
527 /* These are two obsolete opcodes */
530 "%s is obsolete and not implemented",
531 acpi_ps_get_opcode_name(walk_state
->opcode
)));
535 default: /* Unknown opcode */
537 ACPI_ERROR((AE_INFO
, "Unknown AML opcode %X",
538 walk_state
->opcode
));
539 status
= AE_AML_BAD_OPCODE
;
543 if (ACPI_SUCCESS(status
)) {
544 /* Store the return value computed above into the target object */
546 status
= acpi_ex_store(return_desc
, operand
[1], walk_state
);
551 if (!walk_state
->result_obj
) {
552 walk_state
->result_obj
= return_desc
;
555 /* Delete return object on error */
557 if (ACPI_FAILURE(status
)) {
558 acpi_ut_remove_reference(return_desc
);
561 return_ACPI_STATUS(status
);
564 /*******************************************************************************
566 * FUNCTION: acpi_ex_opcode_1A_0T_1R
568 * PARAMETERS: walk_state - Current state (contains AML opcode)
572 * DESCRIPTION: Execute opcode with one argument, no target, and a return value
574 ******************************************************************************/
576 acpi_status
acpi_ex_opcode_1A_0T_1R(struct acpi_walk_state
*walk_state
)
578 union acpi_operand_object
**operand
= &walk_state
->operands
[0];
579 union acpi_operand_object
*temp_desc
;
580 union acpi_operand_object
*return_desc
= NULL
;
581 acpi_status status
= AE_OK
;
585 ACPI_FUNCTION_TRACE_STR("ex_opcode_1A_0T_1R",
586 acpi_ps_get_opcode_name(walk_state
->opcode
));
588 /* Examine the AML opcode */
590 switch (walk_state
->opcode
) {
591 case AML_LNOT_OP
: /* LNot (Operand) */
593 return_desc
= acpi_ut_create_internal_object(ACPI_TYPE_INTEGER
);
595 status
= AE_NO_MEMORY
;
600 * Set result to ONES (TRUE) if Value == 0. Note:
601 * return_desc->Integer.Value is initially == 0 (FALSE) from above.
603 if (!operand
[0]->integer
.value
) {
604 return_desc
->integer
.value
= ACPI_INTEGER_MAX
;
608 case AML_DECREMENT_OP
: /* Decrement (Operand) */
609 case AML_INCREMENT_OP
: /* Increment (Operand) */
612 * Create a new integer. Can't just get the base integer and
613 * increment it because it may be an Arg or Field.
615 return_desc
= acpi_ut_create_internal_object(ACPI_TYPE_INTEGER
);
617 status
= AE_NO_MEMORY
;
622 * Since we are expecting a Reference operand, it can be either a
623 * NS Node or an internal object.
625 temp_desc
= operand
[0];
626 if (ACPI_GET_DESCRIPTOR_TYPE(temp_desc
) ==
627 ACPI_DESC_TYPE_OPERAND
) {
628 /* Internal reference object - prevent deletion */
630 acpi_ut_add_reference(temp_desc
);
634 * Convert the Reference operand to an Integer (This removes a
635 * reference on the Operand[0] object)
637 * NOTE: We use LNOT_OP here in order to force resolution of the
638 * reference operand to an actual integer.
641 acpi_ex_resolve_operands(AML_LNOT_OP
, &temp_desc
,
643 if (ACPI_FAILURE(status
)) {
644 ACPI_EXCEPTION((AE_INFO
, status
,
645 "While resolving operands for [%s]",
646 acpi_ps_get_opcode_name(walk_state
->
653 * temp_desc is now guaranteed to be an Integer object --
654 * Perform the actual increment or decrement
656 if (walk_state
->opcode
== AML_INCREMENT_OP
) {
657 return_desc
->integer
.value
=
658 temp_desc
->integer
.value
+ 1;
660 return_desc
->integer
.value
=
661 temp_desc
->integer
.value
- 1;
664 /* Finished with this Integer object */
666 acpi_ut_remove_reference(temp_desc
);
669 * Store the result back (indirectly) through the original
672 status
= acpi_ex_store(return_desc
, operand
[0], walk_state
);
675 case AML_TYPE_OP
: /* object_type (source_object) */
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
684 /* Get the type of the base object */
687 acpi_ex_resolve_multiple(walk_state
, operand
[0], &type
,
689 if (ACPI_FAILURE(status
)) {
692 /* Allocate a descriptor to hold the type. */
694 return_desc
= acpi_ut_create_internal_object(ACPI_TYPE_INTEGER
);
696 status
= AE_NO_MEMORY
;
700 return_desc
->integer
.value
= type
;
703 case AML_SIZE_OF_OP
: /* size_of (source_object) */
706 * Note: The operand is not resolved at this point because we want to
707 * get the associated object, not its value.
710 /* Get the base object */
712 status
= acpi_ex_resolve_multiple(walk_state
,
715 if (ACPI_FAILURE(status
)) {
720 * The type of the base object must be integer, buffer, string, or
721 * package. All others are not supported.
723 * NOTE: Integer is not specifically supported by the ACPI spec,
724 * but is supported implicitly via implicit operand conversion.
725 * rather than bother with conversion, we just use the byte width
726 * global (4 or 8 bytes).
729 case ACPI_TYPE_INTEGER
:
730 value
= acpi_gbl_integer_byte_width
;
733 case ACPI_TYPE_BUFFER
:
734 value
= temp_desc
->buffer
.length
;
737 case ACPI_TYPE_STRING
:
738 value
= temp_desc
->string
.length
;
741 case ACPI_TYPE_PACKAGE
:
742 value
= temp_desc
->package
.count
;
747 "Operand is not Buf/Int/Str/Pkg - found type %s",
748 acpi_ut_get_type_name(type
)));
749 status
= AE_AML_OPERAND_TYPE
;
754 * Now that we have the size of the object, create a result
755 * object to hold the value
757 return_desc
= acpi_ut_create_internal_object(ACPI_TYPE_INTEGER
);
759 status
= AE_NO_MEMORY
;
763 return_desc
->integer
.value
= value
;
766 case AML_REF_OF_OP
: /* ref_of (source_object) */
769 acpi_ex_get_object_reference(operand
[0], &return_desc
,
771 if (ACPI_FAILURE(status
)) {
776 case AML_DEREF_OF_OP
: /* deref_of (obj_reference | String) */
778 /* Check for a method local or argument, or standalone String */
780 if (ACPI_GET_DESCRIPTOR_TYPE(operand
[0]) !=
781 ACPI_DESC_TYPE_NAMED
) {
782 switch (ACPI_GET_OBJECT_TYPE(operand
[0])) {
783 case ACPI_TYPE_LOCAL_REFERENCE
:
785 * This is a deref_of (local_x | arg_x)
787 * Must resolve/dereference the local/arg reference first
789 switch (operand
[0]->reference
.opcode
) {
793 /* Set Operand[0] to the value of the local/arg */
796 acpi_ds_method_data_get_value
797 (operand
[0]->reference
.opcode
,
798 operand
[0]->reference
.offset
,
799 walk_state
, &temp_desc
);
800 if (ACPI_FAILURE(status
)) {
805 * Delete our reference to the input object and
806 * point to the object just retrieved
808 acpi_ut_remove_reference(operand
[0]);
809 operand
[0] = temp_desc
;
814 /* Get the object to which the reference refers */
817 operand
[0]->reference
.object
;
818 acpi_ut_remove_reference(operand
[0]);
819 operand
[0] = temp_desc
;
824 /* Must be an Index op - handled below */
829 case ACPI_TYPE_STRING
:
832 * This is a deref_of (String). The string is a reference
833 * to a named ACPI object.
835 * 1) Find the owning Node
836 * 2) Dereference the node to an actual object. Could be a
837 * Field, so we need to resolve the node to a value.
840 acpi_ns_get_node_by_path(operand
[0]->string
.
845 ACPI_NS_SEARCH_PARENT
,
846 ACPI_CAST_INDIRECT_PTR
850 if (ACPI_FAILURE(status
)) {
855 acpi_ex_resolve_node_to_value
856 (ACPI_CAST_INDIRECT_PTR
857 (struct acpi_namespace_node
, &return_desc
),
863 status
= AE_AML_OPERAND_TYPE
;
868 /* Operand[0] may have changed from the code above */
870 if (ACPI_GET_DESCRIPTOR_TYPE(operand
[0]) ==
871 ACPI_DESC_TYPE_NAMED
) {
873 * This is a deref_of (object_reference)
874 * Get the actual object from the Node (This is the dereference).
875 * This case may only happen when a local_x or arg_x is
876 * dereferenced above.
878 return_desc
= acpi_ns_get_attached_object((struct
882 acpi_ut_add_reference(return_desc
);
885 * This must be a reference object produced by either the
886 * Index() or ref_of() operator
888 switch (operand
[0]->reference
.opcode
) {
892 * The target type for the Index operator must be
893 * either a Buffer or a Package
895 switch (operand
[0]->reference
.target_type
) {
896 case ACPI_TYPE_BUFFER_FIELD
:
899 operand
[0]->reference
.object
;
902 * Create a new object that contains one element of the
903 * buffer -- the element pointed to by the index.
905 * NOTE: index into a buffer is NOT a pointer to a
906 * sub-buffer of the main buffer, it is only a pointer to a
907 * single element (byte) of the buffer!
910 acpi_ut_create_internal_object
913 status
= AE_NO_MEMORY
;
918 * Since we are returning the value of the buffer at the
919 * indexed location, we don't need to add an additional
920 * reference to the buffer itself.
922 return_desc
->integer
.value
=
924 pointer
[operand
[0]->reference
.
928 case ACPI_TYPE_PACKAGE
:
931 * Return the referenced element of the package. We must
932 * add another reference to the referenced object, however.
935 *(operand
[0]->reference
.where
);
937 acpi_ut_add_reference
946 "Unknown Index target_type %X in obj %p",
947 operand
[0]->reference
.
948 target_type
, operand
[0]));
949 status
= AE_AML_OPERAND_TYPE
;
956 return_desc
= operand
[0]->reference
.object
;
958 if (ACPI_GET_DESCRIPTOR_TYPE(return_desc
) ==
959 ACPI_DESC_TYPE_NAMED
) {
962 acpi_ns_get_attached_object((struct
968 /* Add another reference to the object! */
970 acpi_ut_add_reference(return_desc
);
975 "Unknown opcode in ref(%p) - %X",
977 operand
[0]->reference
.opcode
));
987 ACPI_ERROR((AE_INFO
, "Unknown AML opcode %X",
988 walk_state
->opcode
));
989 status
= AE_AML_BAD_OPCODE
;
995 /* Delete return object on error */
997 if (ACPI_FAILURE(status
)) {
998 acpi_ut_remove_reference(return_desc
);
1001 walk_state
->result_obj
= return_desc
;
1002 return_ACPI_STATUS(status
);