xref: /openbmc/linux/drivers/acpi/acpica/exoparg1.c (revision cfbb9be8)
1 /******************************************************************************
2  *
3  * Module Name: exoparg1 - AML execution - opcodes with 1 argument
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2018, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43 
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acparser.h"
47 #include "acdispat.h"
48 #include "acinterp.h"
49 #include "amlcode.h"
50 #include "acnamesp.h"
51 
52 #define _COMPONENT          ACPI_EXECUTER
53 ACPI_MODULE_NAME("exoparg1")
54 
55 /*!
56  * Naming convention for AML interpreter execution routines.
57  *
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:
61  *
62  *      AcpiExOpcode_xA_yT_zR
63  *
64  * Where:
65  *
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).
72  *
73  * The AcpiExOpcode* functions are called via the Dispatcher component with
74  * fully resolved operands.
75 !*/
76 /*******************************************************************************
77  *
78  * FUNCTION:    acpi_ex_opcode_0A_0T_1R
79  *
80  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
81  *
82  * RETURN:      Status
83  *
84  * DESCRIPTION: Execute operator with no operands, one return value
85  *
86  ******************************************************************************/
87 acpi_status acpi_ex_opcode_0A_0T_1R(struct acpi_walk_state *walk_state)
88 {
89 	acpi_status status = AE_OK;
90 	union acpi_operand_object *return_desc = NULL;
91 
92 	ACPI_FUNCTION_TRACE_STR(ex_opcode_0A_0T_1R,
93 				acpi_ps_get_opcode_name(walk_state->opcode));
94 
95 	/* Examine the AML opcode */
96 
97 	switch (walk_state->opcode) {
98 	case AML_TIMER_OP:	/*  Timer () */
99 
100 		/* Create a return object of type Integer */
101 
102 		return_desc =
103 		    acpi_ut_create_integer_object(acpi_os_get_timer());
104 		if (!return_desc) {
105 			status = AE_NO_MEMORY;
106 			goto cleanup;
107 		}
108 		break;
109 
110 	default:		/*  Unknown opcode  */
111 
112 		ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
113 			    walk_state->opcode));
114 		status = AE_AML_BAD_OPCODE;
115 		break;
116 	}
117 
118 cleanup:
119 
120 	/* Delete return object on error */
121 
122 	if ((ACPI_FAILURE(status)) || walk_state->result_obj) {
123 		acpi_ut_remove_reference(return_desc);
124 		walk_state->result_obj = NULL;
125 	} else {
126 		/* Save the return value */
127 
128 		walk_state->result_obj = return_desc;
129 	}
130 
131 	return_ACPI_STATUS(status);
132 }
133 
134 /*******************************************************************************
135  *
136  * FUNCTION:    acpi_ex_opcode_1A_0T_0R
137  *
138  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
139  *
140  * RETURN:      Status
141  *
142  * DESCRIPTION: Execute Type 1 monadic operator with numeric operand on
143  *              object stack
144  *
145  ******************************************************************************/
146 
147 acpi_status acpi_ex_opcode_1A_0T_0R(struct acpi_walk_state *walk_state)
148 {
149 	union acpi_operand_object **operand = &walk_state->operands[0];
150 	acpi_status status = AE_OK;
151 
152 	ACPI_FUNCTION_TRACE_STR(ex_opcode_1A_0T_0R,
153 				acpi_ps_get_opcode_name(walk_state->opcode));
154 
155 	/* Examine the AML opcode */
156 
157 	switch (walk_state->opcode) {
158 	case AML_RELEASE_OP:	/*  Release (mutex_object) */
159 
160 		status = acpi_ex_release_mutex(operand[0], walk_state);
161 		break;
162 
163 	case AML_RESET_OP:	/*  Reset (event_object) */
164 
165 		status = acpi_ex_system_reset_event(operand[0]);
166 		break;
167 
168 	case AML_SIGNAL_OP:	/*  Signal (event_object) */
169 
170 		status = acpi_ex_system_signal_event(operand[0]);
171 		break;
172 
173 	case AML_SLEEP_OP:	/*  Sleep (msec_time) */
174 
175 		status = acpi_ex_system_do_sleep(operand[0]->integer.value);
176 		break;
177 
178 	case AML_STALL_OP:	/*  Stall (usec_time) */
179 
180 		status =
181 		    acpi_ex_system_do_stall((u32) operand[0]->integer.value);
182 		break;
183 
184 	case AML_UNLOAD_OP:	/*  Unload (Handle) */
185 
186 		status = acpi_ex_unload_table(operand[0]);
187 		break;
188 
189 	default:		/*  Unknown opcode  */
190 
191 		ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
192 			    walk_state->opcode));
193 		status = AE_AML_BAD_OPCODE;
194 		break;
195 	}
196 
197 	return_ACPI_STATUS(status);
198 }
199 
200 /*******************************************************************************
201  *
202  * FUNCTION:    acpi_ex_opcode_1A_1T_0R
203  *
204  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
205  *
206  * RETURN:      Status
207  *
208  * DESCRIPTION: Execute opcode with one argument, one target, and no
209  *              return value.
210  *
211  ******************************************************************************/
212 
213 acpi_status acpi_ex_opcode_1A_1T_0R(struct acpi_walk_state *walk_state)
214 {
215 	acpi_status status = AE_OK;
216 	union acpi_operand_object **operand = &walk_state->operands[0];
217 
218 	ACPI_FUNCTION_TRACE_STR(ex_opcode_1A_1T_0R,
219 				acpi_ps_get_opcode_name(walk_state->opcode));
220 
221 	/* Examine the AML opcode */
222 
223 	switch (walk_state->opcode) {
224 	case AML_LOAD_OP:
225 
226 		status = acpi_ex_load_op(operand[0], operand[1], walk_state);
227 		break;
228 
229 	default:		/* Unknown opcode */
230 
231 		ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
232 			    walk_state->opcode));
233 		status = AE_AML_BAD_OPCODE;
234 		goto cleanup;
235 	}
236 
237 cleanup:
238 
239 	return_ACPI_STATUS(status);
240 }
241 
242 /*******************************************************************************
243  *
244  * FUNCTION:    acpi_ex_opcode_1A_1T_1R
245  *
246  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
247  *
248  * RETURN:      Status
249  *
250  * DESCRIPTION: Execute opcode with one argument, one target, and a
251  *              return value.
252  *
253  ******************************************************************************/
254 
255 acpi_status acpi_ex_opcode_1A_1T_1R(struct acpi_walk_state *walk_state)
256 {
257 	acpi_status status = AE_OK;
258 	union acpi_operand_object **operand = &walk_state->operands[0];
259 	union acpi_operand_object *return_desc = NULL;
260 	union acpi_operand_object *return_desc2 = NULL;
261 	u32 temp32;
262 	u32 i;
263 	u64 power_of_ten;
264 	u64 digit;
265 
266 	ACPI_FUNCTION_TRACE_STR(ex_opcode_1A_1T_1R,
267 				acpi_ps_get_opcode_name(walk_state->opcode));
268 
269 	/* Examine the AML opcode */
270 
271 	switch (walk_state->opcode) {
272 	case AML_BIT_NOT_OP:
273 	case AML_FIND_SET_LEFT_BIT_OP:
274 	case AML_FIND_SET_RIGHT_BIT_OP:
275 	case AML_FROM_BCD_OP:
276 	case AML_TO_BCD_OP:
277 	case AML_CONDITIONAL_REF_OF_OP:
278 
279 		/* Create a return object of type Integer for these opcodes */
280 
281 		return_desc = acpi_ut_create_internal_object(ACPI_TYPE_INTEGER);
282 		if (!return_desc) {
283 			status = AE_NO_MEMORY;
284 			goto cleanup;
285 		}
286 
287 		switch (walk_state->opcode) {
288 		case AML_BIT_NOT_OP:	/* Not (Operand, Result)  */
289 
290 			return_desc->integer.value = ~operand[0]->integer.value;
291 			break;
292 
293 		case AML_FIND_SET_LEFT_BIT_OP:	/* find_set_left_bit (Operand, Result) */
294 
295 			return_desc->integer.value = operand[0]->integer.value;
296 
297 			/*
298 			 * Acpi specification describes Integer type as a little
299 			 * endian unsigned value, so this boundary condition is valid.
300 			 */
301 			for (temp32 = 0; return_desc->integer.value &&
302 			     temp32 < ACPI_INTEGER_BIT_SIZE; ++temp32) {
303 				return_desc->integer.value >>= 1;
304 			}
305 
306 			return_desc->integer.value = temp32;
307 			break;
308 
309 		case AML_FIND_SET_RIGHT_BIT_OP:	/* find_set_right_bit (Operand, Result) */
310 
311 			return_desc->integer.value = operand[0]->integer.value;
312 
313 			/*
314 			 * The Acpi specification describes Integer type as a little
315 			 * endian unsigned value, so this boundary condition is valid.
316 			 */
317 			for (temp32 = 0; return_desc->integer.value &&
318 			     temp32 < ACPI_INTEGER_BIT_SIZE; ++temp32) {
319 				return_desc->integer.value <<= 1;
320 			}
321 
322 			/* Since the bit position is one-based, subtract from 33 (65) */
323 
324 			return_desc->integer.value =
325 			    temp32 ==
326 			    0 ? 0 : (ACPI_INTEGER_BIT_SIZE + 1) - temp32;
327 			break;
328 
329 		case AML_FROM_BCD_OP:	/* from_bcd (BCDValue, Result) */
330 			/*
331 			 * The 64-bit ACPI integer can hold 16 4-bit BCD characters
332 			 * (if table is 32-bit, integer can hold 8 BCD characters)
333 			 * Convert each 4-bit BCD value
334 			 */
335 			power_of_ten = 1;
336 			return_desc->integer.value = 0;
337 			digit = operand[0]->integer.value;
338 
339 			/* Convert each BCD digit (each is one nybble wide) */
340 
341 			for (i = 0;
342 			     (i < acpi_gbl_integer_nybble_width) && (digit > 0);
343 			     i++) {
344 
345 				/* Get the least significant 4-bit BCD digit */
346 
347 				temp32 = ((u32) digit) & 0xF;
348 
349 				/* Check the range of the digit */
350 
351 				if (temp32 > 9) {
352 					ACPI_ERROR((AE_INFO,
353 						    "BCD digit too large (not decimal): 0x%X",
354 						    temp32));
355 
356 					status = AE_AML_NUMERIC_OVERFLOW;
357 					goto cleanup;
358 				}
359 
360 				/* Sum the digit into the result with the current power of 10 */
361 
362 				return_desc->integer.value +=
363 				    (((u64) temp32) * power_of_ten);
364 
365 				/* Shift to next BCD digit */
366 
367 				digit >>= 4;
368 
369 				/* Next power of 10 */
370 
371 				power_of_ten *= 10;
372 			}
373 			break;
374 
375 		case AML_TO_BCD_OP:	/* to_bcd (Operand, Result) */
376 
377 			return_desc->integer.value = 0;
378 			digit = operand[0]->integer.value;
379 
380 			/* Each BCD digit is one nybble wide */
381 
382 			for (i = 0;
383 			     (i < acpi_gbl_integer_nybble_width) && (digit > 0);
384 			     i++) {
385 				(void)acpi_ut_short_divide(digit, 10, &digit,
386 							   &temp32);
387 
388 				/*
389 				 * Insert the BCD digit that resides in the
390 				 * remainder from above
391 				 */
392 				return_desc->integer.value |=
393 				    (((u64) temp32) << ACPI_MUL_4(i));
394 			}
395 
396 			/* Overflow if there is any data left in Digit */
397 
398 			if (digit > 0) {
399 				ACPI_ERROR((AE_INFO,
400 					    "Integer too large to convert to BCD: 0x%8.8X%8.8X",
401 					    ACPI_FORMAT_UINT64(operand[0]->
402 							       integer.value)));
403 				status = AE_AML_NUMERIC_OVERFLOW;
404 				goto cleanup;
405 			}
406 			break;
407 
408 		case AML_CONDITIONAL_REF_OF_OP:	/* cond_ref_of (source_object, Result) */
409 			/*
410 			 * This op is a little strange because the internal return value is
411 			 * different than the return value stored in the result descriptor
412 			 * (There are really two return values)
413 			 */
414 			if ((struct acpi_namespace_node *)operand[0] ==
415 			    acpi_gbl_root_node) {
416 				/*
417 				 * This means that the object does not exist in the namespace,
418 				 * return FALSE
419 				 */
420 				return_desc->integer.value = 0;
421 				goto cleanup;
422 			}
423 
424 			/* Get the object reference, store it, and remove our reference */
425 
426 			status = acpi_ex_get_object_reference(operand[0],
427 							      &return_desc2,
428 							      walk_state);
429 			if (ACPI_FAILURE(status)) {
430 				goto cleanup;
431 			}
432 
433 			status =
434 			    acpi_ex_store(return_desc2, operand[1], walk_state);
435 			acpi_ut_remove_reference(return_desc2);
436 
437 			/* The object exists in the namespace, return TRUE */
438 
439 			return_desc->integer.value = ACPI_UINT64_MAX;
440 			goto cleanup;
441 
442 		default:
443 
444 			/* No other opcodes get here */
445 
446 			break;
447 		}
448 		break;
449 
450 	case AML_STORE_OP:	/* Store (Source, Target) */
451 		/*
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.
455 		 */
456 		status = acpi_ex_store(operand[0], operand[1], walk_state);
457 		if (ACPI_FAILURE(status)) {
458 			return_ACPI_STATUS(status);
459 		}
460 
461 		/* It is possible that the Store already produced a return object */
462 
463 		if (!walk_state->result_obj) {
464 			/*
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.
469 			 */
470 			walk_state->result_obj = operand[0];
471 			walk_state->operands[0] = NULL;	/* Prevent deletion */
472 		}
473 		return_ACPI_STATUS(status);
474 
475 		/*
476 		 * ACPI 2.0 Opcodes
477 		 */
478 	case AML_COPY_OBJECT_OP:	/* copy_object (Source, Target) */
479 
480 		status =
481 		    acpi_ut_copy_iobject_to_iobject(operand[0], &return_desc,
482 						    walk_state);
483 		break;
484 
485 	case AML_TO_DECIMAL_STRING_OP:	/* to_decimal_string (Data, Result) */
486 
487 		status =
488 		    acpi_ex_convert_to_string(operand[0], &return_desc,
489 					      ACPI_EXPLICIT_CONVERT_DECIMAL);
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_HEX_STRING_OP:	/* to_hex_string (Data, Result) */
499 
500 		status =
501 		    acpi_ex_convert_to_string(operand[0], &return_desc,
502 					      ACPI_EXPLICIT_CONVERT_HEX);
503 		if (return_desc == operand[0]) {
504 
505 			/* No conversion performed, add ref to handle return value */
506 
507 			acpi_ut_add_reference(return_desc);
508 		}
509 		break;
510 
511 	case AML_TO_BUFFER_OP:	/* to_buffer (Data, Result) */
512 
513 		status = acpi_ex_convert_to_buffer(operand[0], &return_desc);
514 		if (return_desc == operand[0]) {
515 
516 			/* No conversion performed, add ref to handle return value */
517 
518 			acpi_ut_add_reference(return_desc);
519 		}
520 		break;
521 
522 	case AML_TO_INTEGER_OP:	/* to_integer (Data, Result) */
523 
524 		/* Perform "explicit" conversion */
525 
526 		status =
527 		    acpi_ex_convert_to_integer(operand[0], &return_desc, 0);
528 		if (return_desc == operand[0]) {
529 
530 			/* No conversion performed, add ref to handle return value */
531 
532 			acpi_ut_add_reference(return_desc);
533 		}
534 		break;
535 
536 	case AML_SHIFT_LEFT_BIT_OP:	/* shift_left_bit (Source, bit_num) */
537 	case AML_SHIFT_RIGHT_BIT_OP:	/* shift_right_bit (Source, bit_num) */
538 
539 		/* These are two obsolete opcodes */
540 
541 		ACPI_ERROR((AE_INFO,
542 			    "%s is obsolete and not implemented",
543 			    acpi_ps_get_opcode_name(walk_state->opcode)));
544 		status = AE_SUPPORT;
545 		goto cleanup;
546 
547 	default:		/* Unknown opcode */
548 
549 		ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
550 			    walk_state->opcode));
551 		status = AE_AML_BAD_OPCODE;
552 		goto cleanup;
553 	}
554 
555 	if (ACPI_SUCCESS(status)) {
556 
557 		/* Store the return value computed above into the target object */
558 
559 		status = acpi_ex_store(return_desc, operand[1], walk_state);
560 	}
561 
562 cleanup:
563 
564 	/* Delete return object on error */
565 
566 	if (ACPI_FAILURE(status)) {
567 		acpi_ut_remove_reference(return_desc);
568 	}
569 
570 	/* Save return object on success */
571 
572 	else if (!walk_state->result_obj) {
573 		walk_state->result_obj = return_desc;
574 	}
575 
576 	return_ACPI_STATUS(status);
577 }
578 
579 /*******************************************************************************
580  *
581  * FUNCTION:    acpi_ex_opcode_1A_0T_1R
582  *
583  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
584  *
585  * RETURN:      Status
586  *
587  * DESCRIPTION: Execute opcode with one argument, no target, and a return value
588  *
589  ******************************************************************************/
590 
591 acpi_status acpi_ex_opcode_1A_0T_1R(struct acpi_walk_state *walk_state)
592 {
593 	union acpi_operand_object **operand = &walk_state->operands[0];
594 	union acpi_operand_object *temp_desc;
595 	union acpi_operand_object *return_desc = NULL;
596 	acpi_status status = AE_OK;
597 	u32 type;
598 	u64 value;
599 
600 	ACPI_FUNCTION_TRACE_STR(ex_opcode_1A_0T_1R,
601 				acpi_ps_get_opcode_name(walk_state->opcode));
602 
603 	/* Examine the AML opcode */
604 
605 	switch (walk_state->opcode) {
606 	case AML_LOGICAL_NOT_OP:	/* LNot (Operand) */
607 
608 		return_desc = acpi_ut_create_integer_object((u64) 0);
609 		if (!return_desc) {
610 			status = AE_NO_MEMORY;
611 			goto cleanup;
612 		}
613 
614 		/*
615 		 * Set result to ONES (TRUE) if Value == 0. Note:
616 		 * return_desc->Integer.Value is initially == 0 (FALSE) from above.
617 		 */
618 		if (!operand[0]->integer.value) {
619 			return_desc->integer.value = ACPI_UINT64_MAX;
620 		}
621 		break;
622 
623 	case AML_DECREMENT_OP:	/* Decrement (Operand)  */
624 	case AML_INCREMENT_OP:	/* Increment (Operand)  */
625 		/*
626 		 * Create a new integer. Can't just get the base integer and
627 		 * increment it because it may be an Arg or Field.
628 		 */
629 		return_desc = acpi_ut_create_internal_object(ACPI_TYPE_INTEGER);
630 		if (!return_desc) {
631 			status = AE_NO_MEMORY;
632 			goto cleanup;
633 		}
634 
635 		/*
636 		 * Since we are expecting a Reference operand, it can be either a
637 		 * NS Node or an internal object.
638 		 */
639 		temp_desc = operand[0];
640 		if (ACPI_GET_DESCRIPTOR_TYPE(temp_desc) ==
641 		    ACPI_DESC_TYPE_OPERAND) {
642 
643 			/* Internal reference object - prevent deletion */
644 
645 			acpi_ut_add_reference(temp_desc);
646 		}
647 
648 		/*
649 		 * Convert the Reference operand to an Integer (This removes a
650 		 * reference on the Operand[0] object)
651 		 *
652 		 * NOTE:  We use LNOT_OP here in order to force resolution of the
653 		 * reference operand to an actual integer.
654 		 */
655 		status = acpi_ex_resolve_operands(AML_LOGICAL_NOT_OP,
656 						  &temp_desc, walk_state);
657 		if (ACPI_FAILURE(status)) {
658 			ACPI_EXCEPTION((AE_INFO, status,
659 					"While resolving operands for [%s]",
660 					acpi_ps_get_opcode_name(walk_state->
661 								opcode)));
662 
663 			goto cleanup;
664 		}
665 
666 		/*
667 		 * temp_desc is now guaranteed to be an Integer object --
668 		 * Perform the actual increment or decrement
669 		 */
670 		if (walk_state->opcode == AML_INCREMENT_OP) {
671 			return_desc->integer.value =
672 			    temp_desc->integer.value + 1;
673 		} else {
674 			return_desc->integer.value =
675 			    temp_desc->integer.value - 1;
676 		}
677 
678 		/* Finished with this Integer object */
679 
680 		acpi_ut_remove_reference(temp_desc);
681 
682 		/*
683 		 * Store the result back (indirectly) through the original
684 		 * Reference object
685 		 */
686 		status = acpi_ex_store(return_desc, operand[0], walk_state);
687 		break;
688 
689 	case AML_OBJECT_TYPE_OP:	/* object_type (source_object) */
690 		/*
691 		 * Note: The operand is not resolved at this point because we want to
692 		 * get the associated object, not its value. For example, we don't
693 		 * want to resolve a field_unit to its value, we want the actual
694 		 * field_unit object.
695 		 */
696 
697 		/* Get the type of the base object */
698 
699 		status =
700 		    acpi_ex_resolve_multiple(walk_state, operand[0], &type,
701 					     NULL);
702 		if (ACPI_FAILURE(status)) {
703 			goto cleanup;
704 		}
705 
706 		/* Allocate a descriptor to hold the type. */
707 
708 		return_desc = acpi_ut_create_integer_object((u64) type);
709 		if (!return_desc) {
710 			status = AE_NO_MEMORY;
711 			goto cleanup;
712 		}
713 		break;
714 
715 	case AML_SIZE_OF_OP:	/* size_of (source_object) */
716 		/*
717 		 * Note: The operand is not resolved at this point because we want to
718 		 * get the associated object, not its value.
719 		 */
720 
721 		/* Get the base object */
722 
723 		status =
724 		    acpi_ex_resolve_multiple(walk_state, operand[0], &type,
725 					     &temp_desc);
726 		if (ACPI_FAILURE(status)) {
727 			goto cleanup;
728 		}
729 
730 		/*
731 		 * The type of the base object must be integer, buffer, string, or
732 		 * package. All others are not supported.
733 		 *
734 		 * NOTE: Integer is not specifically supported by the ACPI spec,
735 		 * but is supported implicitly via implicit operand conversion.
736 		 * rather than bother with conversion, we just use the byte width
737 		 * global (4 or 8 bytes).
738 		 */
739 		switch (type) {
740 		case ACPI_TYPE_INTEGER:
741 
742 			value = acpi_gbl_integer_byte_width;
743 			break;
744 
745 		case ACPI_TYPE_STRING:
746 
747 			value = temp_desc->string.length;
748 			break;
749 
750 		case ACPI_TYPE_BUFFER:
751 
752 			/* Buffer arguments may not be evaluated at this point */
753 
754 			status = acpi_ds_get_buffer_arguments(temp_desc);
755 			value = temp_desc->buffer.length;
756 			break;
757 
758 		case ACPI_TYPE_PACKAGE:
759 
760 			/* Package arguments may not be evaluated at this point */
761 
762 			status = acpi_ds_get_package_arguments(temp_desc);
763 			value = temp_desc->package.count;
764 			break;
765 
766 		default:
767 
768 			ACPI_ERROR((AE_INFO,
769 				    "Operand must be Buffer/Integer/String/Package"
770 				    " - found type %s",
771 				    acpi_ut_get_type_name(type)));
772 
773 			status = AE_AML_OPERAND_TYPE;
774 			goto cleanup;
775 		}
776 
777 		if (ACPI_FAILURE(status)) {
778 			goto cleanup;
779 		}
780 
781 		/*
782 		 * Now that we have the size of the object, create a result
783 		 * object to hold the value
784 		 */
785 		return_desc = acpi_ut_create_integer_object(value);
786 		if (!return_desc) {
787 			status = AE_NO_MEMORY;
788 			goto cleanup;
789 		}
790 		break;
791 
792 	case AML_REF_OF_OP:	/* ref_of (source_object) */
793 
794 		status =
795 		    acpi_ex_get_object_reference(operand[0], &return_desc,
796 						 walk_state);
797 		if (ACPI_FAILURE(status)) {
798 			goto cleanup;
799 		}
800 		break;
801 
802 	case AML_DEREF_OF_OP:	/* deref_of (obj_reference | String) */
803 
804 		/* Check for a method local or argument, or standalone String */
805 
806 		if (ACPI_GET_DESCRIPTOR_TYPE(operand[0]) ==
807 		    ACPI_DESC_TYPE_NAMED) {
808 			temp_desc =
809 			    acpi_ns_get_attached_object((struct
810 							 acpi_namespace_node *)
811 							operand[0]);
812 			if (temp_desc
813 			    && ((temp_desc->common.type == ACPI_TYPE_STRING)
814 				|| (temp_desc->common.type ==
815 				    ACPI_TYPE_LOCAL_REFERENCE))) {
816 				operand[0] = temp_desc;
817 				acpi_ut_add_reference(temp_desc);
818 			} else {
819 				status = AE_AML_OPERAND_TYPE;
820 				goto cleanup;
821 			}
822 		} else {
823 			switch ((operand[0])->common.type) {
824 			case ACPI_TYPE_LOCAL_REFERENCE:
825 				/*
826 				 * This is a deref_of (local_x | arg_x)
827 				 *
828 				 * Must resolve/dereference the local/arg reference first
829 				 */
830 				switch (operand[0]->reference.class) {
831 				case ACPI_REFCLASS_LOCAL:
832 				case ACPI_REFCLASS_ARG:
833 
834 					/* Set Operand[0] to the value of the local/arg */
835 
836 					status =
837 					    acpi_ds_method_data_get_value
838 					    (operand[0]->reference.class,
839 					     operand[0]->reference.value,
840 					     walk_state, &temp_desc);
841 					if (ACPI_FAILURE(status)) {
842 						goto cleanup;
843 					}
844 
845 					/*
846 					 * Delete our reference to the input object and
847 					 * point to the object just retrieved
848 					 */
849 					acpi_ut_remove_reference(operand[0]);
850 					operand[0] = temp_desc;
851 					break;
852 
853 				case ACPI_REFCLASS_REFOF:
854 
855 					/* Get the object to which the reference refers */
856 
857 					temp_desc =
858 					    operand[0]->reference.object;
859 					acpi_ut_remove_reference(operand[0]);
860 					operand[0] = temp_desc;
861 					break;
862 
863 				default:
864 
865 					/* Must be an Index op - handled below */
866 					break;
867 				}
868 				break;
869 
870 			case ACPI_TYPE_STRING:
871 
872 				break;
873 
874 			default:
875 
876 				status = AE_AML_OPERAND_TYPE;
877 				goto cleanup;
878 			}
879 		}
880 
881 		if (ACPI_GET_DESCRIPTOR_TYPE(operand[0]) !=
882 		    ACPI_DESC_TYPE_NAMED) {
883 			if ((operand[0])->common.type == ACPI_TYPE_STRING) {
884 				/*
885 				 * This is a deref_of (String). The string is a reference
886 				 * to a named ACPI object.
887 				 *
888 				 * 1) Find the owning Node
889 				 * 2) Dereference the node to an actual object. Could be a
890 				 *    Field, so we need to resolve the node to a value.
891 				 */
892 				status =
893 				    acpi_ns_get_node_unlocked(walk_state->
894 							      scope_info->scope.
895 							      node,
896 							      operand[0]->
897 							      string.pointer,
898 							      ACPI_NS_SEARCH_PARENT,
899 							      ACPI_CAST_INDIRECT_PTR
900 							      (struct
901 							       acpi_namespace_node,
902 							       &return_desc));
903 				if (ACPI_FAILURE(status)) {
904 					goto cleanup;
905 				}
906 
907 				status =
908 				    acpi_ex_resolve_node_to_value
909 				    (ACPI_CAST_INDIRECT_PTR
910 				     (struct acpi_namespace_node, &return_desc),
911 				     walk_state);
912 				goto cleanup;
913 			}
914 		}
915 
916 		/* Operand[0] may have changed from the code above */
917 
918 		if (ACPI_GET_DESCRIPTOR_TYPE(operand[0]) ==
919 		    ACPI_DESC_TYPE_NAMED) {
920 			/*
921 			 * This is a deref_of (object_reference)
922 			 * Get the actual object from the Node (This is the dereference).
923 			 * This case may only happen when a local_x or arg_x is
924 			 * dereferenced above, or for references to device and
925 			 * thermal objects.
926 			 */
927 			switch (((struct acpi_namespace_node *)operand[0])->
928 				type) {
929 			case ACPI_TYPE_DEVICE:
930 			case ACPI_TYPE_THERMAL:
931 
932 				/* These types have no node subobject, return the NS node */
933 
934 				return_desc = operand[0];
935 				break;
936 
937 			default:
938 				/* For most types, get the object attached to the node */
939 
940 				return_desc = acpi_ns_get_attached_object((struct acpi_namespace_node *)operand[0]);
941 				acpi_ut_add_reference(return_desc);
942 				break;
943 			}
944 		} else {
945 			/*
946 			 * This must be a reference object produced by either the
947 			 * Index() or ref_of() operator
948 			 */
949 			switch (operand[0]->reference.class) {
950 			case ACPI_REFCLASS_INDEX:
951 				/*
952 				 * The target type for the Index operator must be
953 				 * either a Buffer or a Package
954 				 */
955 				switch (operand[0]->reference.target_type) {
956 				case ACPI_TYPE_BUFFER_FIELD:
957 
958 					temp_desc =
959 					    operand[0]->reference.object;
960 
961 					/*
962 					 * Create a new object that contains one element of the
963 					 * buffer -- the element pointed to by the index.
964 					 *
965 					 * NOTE: index into a buffer is NOT a pointer to a
966 					 * sub-buffer of the main buffer, it is only a pointer to a
967 					 * single element (byte) of the buffer!
968 					 *
969 					 * Since we are returning the value of the buffer at the
970 					 * indexed location, we don't need to add an additional
971 					 * reference to the buffer itself.
972 					 */
973 					return_desc =
974 					    acpi_ut_create_integer_object((u64)
975 									  temp_desc->buffer.pointer[operand[0]->reference.value]);
976 					if (!return_desc) {
977 						status = AE_NO_MEMORY;
978 						goto cleanup;
979 					}
980 					break;
981 
982 				case ACPI_TYPE_PACKAGE:
983 					/*
984 					 * Return the referenced element of the package. We must
985 					 * add another reference to the referenced object, however.
986 					 */
987 					return_desc =
988 					    *(operand[0]->reference.where);
989 					if (!return_desc) {
990 						/*
991 						 * Element is NULL, do not allow the dereference.
992 						 * This provides compatibility with other ACPI
993 						 * implementations.
994 						 */
995 						return_ACPI_STATUS
996 						    (AE_AML_UNINITIALIZED_ELEMENT);
997 					}
998 
999 					acpi_ut_add_reference(return_desc);
1000 					break;
1001 
1002 				default:
1003 
1004 					ACPI_ERROR((AE_INFO,
1005 						    "Unknown Index TargetType 0x%X in reference object %p",
1006 						    operand[0]->reference.
1007 						    target_type, operand[0]));
1008 
1009 					status = AE_AML_OPERAND_TYPE;
1010 					goto cleanup;
1011 				}
1012 				break;
1013 
1014 			case ACPI_REFCLASS_REFOF:
1015 
1016 				return_desc = operand[0]->reference.object;
1017 
1018 				if (ACPI_GET_DESCRIPTOR_TYPE(return_desc) ==
1019 				    ACPI_DESC_TYPE_NAMED) {
1020 					return_desc =
1021 					    acpi_ns_get_attached_object((struct
1022 									 acpi_namespace_node
1023 									 *)
1024 									return_desc);
1025 					if (!return_desc) {
1026 						break;
1027 					}
1028 
1029 					/*
1030 					 * June 2013:
1031 					 * buffer_fields/field_units require additional resolution
1032 					 */
1033 					switch (return_desc->common.type) {
1034 					case ACPI_TYPE_BUFFER_FIELD:
1035 					case ACPI_TYPE_LOCAL_REGION_FIELD:
1036 					case ACPI_TYPE_LOCAL_BANK_FIELD:
1037 					case ACPI_TYPE_LOCAL_INDEX_FIELD:
1038 
1039 						status =
1040 						    acpi_ex_read_data_from_field
1041 						    (walk_state, return_desc,
1042 						     &temp_desc);
1043 						if (ACPI_FAILURE(status)) {
1044 							goto cleanup;
1045 						}
1046 
1047 						return_desc = temp_desc;
1048 						break;
1049 
1050 					default:
1051 
1052 						/* Add another reference to the object */
1053 
1054 						acpi_ut_add_reference
1055 						    (return_desc);
1056 						break;
1057 					}
1058 				}
1059 				break;
1060 
1061 			default:
1062 
1063 				ACPI_ERROR((AE_INFO,
1064 					    "Unknown class in reference(%p) - 0x%2.2X",
1065 					    operand[0],
1066 					    operand[0]->reference.class));
1067 
1068 				status = AE_TYPE;
1069 				goto cleanup;
1070 			}
1071 		}
1072 		break;
1073 
1074 	default:
1075 
1076 		ACPI_ERROR((AE_INFO, "Unknown AML opcode 0x%X",
1077 			    walk_state->opcode));
1078 
1079 		status = AE_AML_BAD_OPCODE;
1080 		goto cleanup;
1081 	}
1082 
1083 cleanup:
1084 
1085 	/* Delete return object on error */
1086 
1087 	if (ACPI_FAILURE(status)) {
1088 		acpi_ut_remove_reference(return_desc);
1089 	}
1090 
1091 	/* Save return object on success */
1092 
1093 	else {
1094 		walk_state->result_obj = return_desc;
1095 	}
1096 
1097 	return_ACPI_STATUS(status);
1098 }
1099