xref: /linux/drivers/acpi/acpica/exprep.c (revision c0c914eca7f251c70facc37dfebeaf176601918d)
1 /******************************************************************************
2  *
3  * Module Name: exprep - ACPI AML field prep utilities
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2016, 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 "acinterp.h"
47 #include "amlcode.h"
48 #include "acnamesp.h"
49 #include "acdispat.h"
50 
51 #define _COMPONENT          ACPI_EXECUTER
52 ACPI_MODULE_NAME("exprep")
53 
54 /* Local prototypes */
55 static u32
56 acpi_ex_decode_field_access(union acpi_operand_object *obj_desc,
57 			    u8 field_flags, u32 * return_byte_alignment);
58 
59 #ifdef ACPI_UNDER_DEVELOPMENT
60 
61 static u32
62 acpi_ex_generate_access(u32 field_bit_offset,
63 			u32 field_bit_length, u32 region_length);
64 
65 /*******************************************************************************
66  *
67  * FUNCTION:    acpi_ex_generate_access
68  *
69  * PARAMETERS:  field_bit_offset    - Start of field within parent region/buffer
70  *              field_bit_length    - Length of field in bits
71  *              region_length       - Length of parent in bytes
72  *
73  * RETURN:      Field granularity (8, 16, 32 or 64) and
74  *              byte_alignment (1, 2, 3, or 4)
75  *
76  * DESCRIPTION: Generate an optimal access width for fields defined with the
77  *              any_acc keyword.
78  *
79  * NOTE: Need to have the region_length in order to check for boundary
80  *       conditions (end-of-region). However, the region_length is a deferred
81  *       operation. Therefore, to complete this implementation, the generation
82  *       of this access width must be deferred until the region length has
83  *       been evaluated.
84  *
85  ******************************************************************************/
86 
87 static u32
88 acpi_ex_generate_access(u32 field_bit_offset,
89 			u32 field_bit_length, u32 region_length)
90 {
91 	u32 field_byte_length;
92 	u32 field_byte_offset;
93 	u32 field_byte_end_offset;
94 	u32 access_byte_width;
95 	u32 field_start_offset;
96 	u32 field_end_offset;
97 	u32 minimum_access_width = 0xFFFFFFFF;
98 	u32 minimum_accesses = 0xFFFFFFFF;
99 	u32 accesses;
100 
101 	ACPI_FUNCTION_TRACE(ex_generate_access);
102 
103 	/* Round Field start offset and length to "minimal" byte boundaries */
104 
105 	field_byte_offset = ACPI_DIV_8(ACPI_ROUND_DOWN(field_bit_offset, 8));
106 
107 	field_byte_end_offset =
108 	    ACPI_DIV_8(ACPI_ROUND_UP(field_bit_length + field_bit_offset, 8));
109 
110 	field_byte_length = field_byte_end_offset - field_byte_offset;
111 
112 	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
113 			  "Bit length %u, Bit offset %u\n",
114 			  field_bit_length, field_bit_offset));
115 
116 	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
117 			  "Byte Length %u, Byte Offset %u, End Offset %u\n",
118 			  field_byte_length, field_byte_offset,
119 			  field_byte_end_offset));
120 
121 	/*
122 	 * Iterative search for the maximum access width that is both aligned
123 	 * and does not go beyond the end of the region
124 	 *
125 	 * Start at byte_acc and work upwards to qword_acc max. (1,2,4,8 bytes)
126 	 */
127 	for (access_byte_width = 1; access_byte_width <= 8;
128 	     access_byte_width <<= 1) {
129 		/*
130 		 * 1) Round end offset up to next access boundary and make sure that
131 		 *    this does not go beyond the end of the parent region.
132 		 * 2) When the Access width is greater than the field_byte_length, we
133 		 *    are done. (This does not optimize for the perfectly aligned
134 		 *    case yet).
135 		 */
136 		if (ACPI_ROUND_UP(field_byte_end_offset, access_byte_width) <=
137 		    region_length) {
138 			field_start_offset =
139 			    ACPI_ROUND_DOWN(field_byte_offset,
140 					    access_byte_width) /
141 			    access_byte_width;
142 
143 			field_end_offset =
144 			    ACPI_ROUND_UP((field_byte_length +
145 					   field_byte_offset),
146 					  access_byte_width) /
147 			    access_byte_width;
148 
149 			accesses = field_end_offset - field_start_offset;
150 
151 			ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
152 					  "AccessWidth %u end is within region\n",
153 					  access_byte_width));
154 
155 			ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
156 					  "Field Start %u, Field End %u -- requires %u accesses\n",
157 					  field_start_offset, field_end_offset,
158 					  accesses));
159 
160 			/* Single access is optimal */
161 
162 			if (accesses <= 1) {
163 				ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
164 						  "Entire field can be accessed "
165 						  "with one operation of size %u\n",
166 						  access_byte_width));
167 				return_VALUE(access_byte_width);
168 			}
169 
170 			/*
171 			 * Fits in the region, but requires more than one read/write.
172 			 * try the next wider access on next iteration
173 			 */
174 			if (accesses < minimum_accesses) {
175 				minimum_accesses = accesses;
176 				minimum_access_width = access_byte_width;
177 			}
178 		} else {
179 			ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
180 					  "AccessWidth %u end is NOT within region\n",
181 					  access_byte_width));
182 			if (access_byte_width == 1) {
183 				ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
184 						  "Field goes beyond end-of-region!\n"));
185 
186 				/* Field does not fit in the region at all */
187 
188 				return_VALUE(0);
189 			}
190 
191 			/*
192 			 * This width goes beyond the end-of-region, back off to
193 			 * previous access
194 			 */
195 			ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
196 					  "Backing off to previous optimal access width of %u\n",
197 					  minimum_access_width));
198 			return_VALUE(minimum_access_width);
199 		}
200 	}
201 
202 	/*
203 	 * Could not read/write field with one operation,
204 	 * just use max access width
205 	 */
206 	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
207 			  "Cannot access field in one operation, using width 8\n"));
208 
209 	return_VALUE(8);
210 }
211 #endif				/* ACPI_UNDER_DEVELOPMENT */
212 
213 /*******************************************************************************
214  *
215  * FUNCTION:    acpi_ex_decode_field_access
216  *
217  * PARAMETERS:  obj_desc            - Field object
218  *              field_flags         - Encoded fieldflags (contains access bits)
219  *              return_byte_alignment - Where the byte alignment is returned
220  *
221  * RETURN:      Field granularity (8, 16, 32 or 64) and
222  *              byte_alignment (1, 2, 3, or 4)
223  *
224  * DESCRIPTION: Decode the access_type bits of a field definition.
225  *
226  ******************************************************************************/
227 
228 static u32
229 acpi_ex_decode_field_access(union acpi_operand_object *obj_desc,
230 			    u8 field_flags, u32 * return_byte_alignment)
231 {
232 	u32 access;
233 	u32 byte_alignment;
234 	u32 bit_length;
235 
236 	ACPI_FUNCTION_TRACE(ex_decode_field_access);
237 
238 	access = (field_flags & AML_FIELD_ACCESS_TYPE_MASK);
239 
240 	switch (access) {
241 	case AML_FIELD_ACCESS_ANY:
242 
243 #ifdef ACPI_UNDER_DEVELOPMENT
244 		byte_alignment =
245 		    acpi_ex_generate_access(obj_desc->common_field.
246 					    start_field_bit_offset,
247 					    obj_desc->common_field.bit_length,
248 					    0xFFFFFFFF
249 					    /* Temp until we pass region_length as parameter */
250 		    );
251 		bit_length = byte_alignment * 8;
252 #endif
253 
254 		byte_alignment = 1;
255 		bit_length = 8;
256 		break;
257 
258 	case AML_FIELD_ACCESS_BYTE:
259 	case AML_FIELD_ACCESS_BUFFER:	/* ACPI 2.0 (SMBus Buffer) */
260 
261 		byte_alignment = 1;
262 		bit_length = 8;
263 		break;
264 
265 	case AML_FIELD_ACCESS_WORD:
266 
267 		byte_alignment = 2;
268 		bit_length = 16;
269 		break;
270 
271 	case AML_FIELD_ACCESS_DWORD:
272 
273 		byte_alignment = 4;
274 		bit_length = 32;
275 		break;
276 
277 	case AML_FIELD_ACCESS_QWORD:	/* ACPI 2.0 */
278 
279 		byte_alignment = 8;
280 		bit_length = 64;
281 		break;
282 
283 	default:
284 
285 		/* Invalid field access type */
286 
287 		ACPI_ERROR((AE_INFO, "Unknown field access type 0x%X", access));
288 
289 		return_UINT32(0);
290 	}
291 
292 	if (obj_desc->common.type == ACPI_TYPE_BUFFER_FIELD) {
293 		/*
294 		 * buffer_field access can be on any byte boundary, so the
295 		 * byte_alignment is always 1 byte -- regardless of any byte_alignment
296 		 * implied by the field access type.
297 		 */
298 		byte_alignment = 1;
299 	}
300 
301 	*return_byte_alignment = byte_alignment;
302 	return_UINT32(bit_length);
303 }
304 
305 /*******************************************************************************
306  *
307  * FUNCTION:    acpi_ex_prep_common_field_object
308  *
309  * PARAMETERS:  obj_desc            - The field object
310  *              field_flags         - Access, lock_rule, and update_rule.
311  *                                    The format of a field_flag is described
312  *                                    in the ACPI specification
313  *              field_attribute     - Special attributes (not used)
314  *              field_bit_position  - Field start position
315  *              field_bit_length    - Field length in number of bits
316  *
317  * RETURN:      Status
318  *
319  * DESCRIPTION: Initialize the areas of the field object that are common
320  *              to the various types of fields. Note: This is very "sensitive"
321  *              code because we are solving the general case for field
322  *              alignment.
323  *
324  ******************************************************************************/
325 
326 acpi_status
327 acpi_ex_prep_common_field_object(union acpi_operand_object *obj_desc,
328 				 u8 field_flags,
329 				 u8 field_attribute,
330 				 u32 field_bit_position, u32 field_bit_length)
331 {
332 	u32 access_bit_width;
333 	u32 byte_alignment;
334 	u32 nearest_byte_address;
335 
336 	ACPI_FUNCTION_TRACE(ex_prep_common_field_object);
337 
338 	/*
339 	 * Note: the structure being initialized is the
340 	 * ACPI_COMMON_FIELD_INFO;  No structure fields outside of the common
341 	 * area are initialized by this procedure.
342 	 */
343 	obj_desc->common_field.field_flags = field_flags;
344 	obj_desc->common_field.attribute = field_attribute;
345 	obj_desc->common_field.bit_length = field_bit_length;
346 
347 	/*
348 	 * Decode the access type so we can compute offsets. The access type gives
349 	 * two pieces of information - the width of each field access and the
350 	 * necessary byte_alignment (address granularity) of the access.
351 	 *
352 	 * For any_acc, the access_bit_width is the largest width that is both
353 	 * necessary and possible in an attempt to access the whole field in one
354 	 * I/O operation. However, for any_acc, the byte_alignment is always one
355 	 * byte.
356 	 *
357 	 * For all Buffer Fields, the byte_alignment is always one byte.
358 	 *
359 	 * For all other access types (Byte, Word, Dword, Qword), the Bitwidth is
360 	 * the same (equivalent) as the byte_alignment.
361 	 */
362 	access_bit_width =
363 	    acpi_ex_decode_field_access(obj_desc, field_flags, &byte_alignment);
364 	if (!access_bit_width) {
365 		return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
366 	}
367 
368 	/* Setup width (access granularity) fields (values are: 1, 2, 4, 8) */
369 
370 	obj_desc->common_field.access_byte_width = (u8)
371 	    ACPI_DIV_8(access_bit_width);
372 
373 	/*
374 	 * base_byte_offset is the address of the start of the field within the
375 	 * region. It is the byte address of the first *datum* (field-width data
376 	 * unit) of the field. (i.e., the first datum that contains at least the
377 	 * first *bit* of the field.)
378 	 *
379 	 * Note: byte_alignment is always either equal to the access_bit_width or 8
380 	 * (Byte access), and it defines the addressing granularity of the parent
381 	 * region or buffer.
382 	 */
383 	nearest_byte_address =
384 	    ACPI_ROUND_BITS_DOWN_TO_BYTES(field_bit_position);
385 	obj_desc->common_field.base_byte_offset = (u32)
386 	    ACPI_ROUND_DOWN(nearest_byte_address, byte_alignment);
387 
388 	/*
389 	 * start_field_bit_offset is the offset of the first bit of the field within
390 	 * a field datum.
391 	 */
392 	obj_desc->common_field.start_field_bit_offset = (u8)
393 	    (field_bit_position -
394 	     ACPI_MUL_8(obj_desc->common_field.base_byte_offset));
395 
396 	return_ACPI_STATUS(AE_OK);
397 }
398 
399 /*******************************************************************************
400  *
401  * FUNCTION:    acpi_ex_prep_field_value
402  *
403  * PARAMETERS:  info    - Contains all field creation info
404  *
405  * RETURN:      Status
406  *
407  * DESCRIPTION: Construct an object of type union acpi_operand_object with a
408  *              subtype of def_field and connect it to the parent Node.
409  *
410  ******************************************************************************/
411 
412 acpi_status acpi_ex_prep_field_value(struct acpi_create_field_info *info)
413 {
414 	union acpi_operand_object *obj_desc;
415 	union acpi_operand_object *second_desc = NULL;
416 	acpi_status status;
417 	u32 access_byte_width;
418 	u32 type;
419 
420 	ACPI_FUNCTION_TRACE(ex_prep_field_value);
421 
422 	/* Parameter validation */
423 
424 	if (info->field_type != ACPI_TYPE_LOCAL_INDEX_FIELD) {
425 		if (!info->region_node) {
426 			ACPI_ERROR((AE_INFO, "Null RegionNode"));
427 			return_ACPI_STATUS(AE_AML_NO_OPERAND);
428 		}
429 
430 		type = acpi_ns_get_type(info->region_node);
431 		if (type != ACPI_TYPE_REGION) {
432 			ACPI_ERROR((AE_INFO,
433 				    "Needed Region, found type 0x%X (%s)", type,
434 				    acpi_ut_get_type_name(type)));
435 
436 			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
437 		}
438 	}
439 
440 	/* Allocate a new field object */
441 
442 	obj_desc = acpi_ut_create_internal_object(info->field_type);
443 	if (!obj_desc) {
444 		return_ACPI_STATUS(AE_NO_MEMORY);
445 	}
446 
447 	/* Initialize areas of the object that are common to all fields */
448 
449 	obj_desc->common_field.node = info->field_node;
450 	status = acpi_ex_prep_common_field_object(obj_desc,
451 						  info->field_flags,
452 						  info->attribute,
453 						  info->field_bit_position,
454 						  info->field_bit_length);
455 	if (ACPI_FAILURE(status)) {
456 		acpi_ut_delete_object_desc(obj_desc);
457 		return_ACPI_STATUS(status);
458 	}
459 
460 	/* Initialize areas of the object that are specific to the field type */
461 
462 	switch (info->field_type) {
463 	case ACPI_TYPE_LOCAL_REGION_FIELD:
464 
465 		obj_desc->field.region_obj =
466 		    acpi_ns_get_attached_object(info->region_node);
467 
468 		/* Fields specific to generic_serial_bus fields */
469 
470 		obj_desc->field.access_length = info->access_length;
471 
472 		if (info->connection_node) {
473 			second_desc = info->connection_node->object;
474 			if (!(second_desc->common.flags & AOPOBJ_DATA_VALID)) {
475 				status =
476 				    acpi_ds_get_buffer_arguments(second_desc);
477 				if (ACPI_FAILURE(status)) {
478 					acpi_ut_delete_object_desc(obj_desc);
479 					return_ACPI_STATUS(status);
480 				}
481 			}
482 
483 			obj_desc->field.resource_buffer =
484 			    second_desc->buffer.pointer;
485 			obj_desc->field.resource_length =
486 			    (u16)second_desc->buffer.length;
487 		} else if (info->resource_buffer) {
488 			obj_desc->field.resource_buffer = info->resource_buffer;
489 			obj_desc->field.resource_length = info->resource_length;
490 		}
491 
492 		obj_desc->field.pin_number_index = info->pin_number_index;
493 
494 		/* Allow full data read from EC address space */
495 
496 		if ((obj_desc->field.region_obj->region.space_id ==
497 		     ACPI_ADR_SPACE_EC)
498 		    && (obj_desc->common_field.bit_length > 8)) {
499 			access_byte_width =
500 			    ACPI_ROUND_BITS_UP_TO_BYTES(obj_desc->common_field.
501 							bit_length);
502 
503 			/* Maximum byte width supported is 255 */
504 
505 			if (access_byte_width < 256) {
506 				obj_desc->common_field.access_byte_width =
507 				    (u8)access_byte_width;
508 			}
509 		}
510 		/* An additional reference for the container */
511 
512 		acpi_ut_add_reference(obj_desc->field.region_obj);
513 
514 		ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
515 				  "RegionField: BitOff %X, Off %X, Gran %X, Region %p\n",
516 				  obj_desc->field.start_field_bit_offset,
517 				  obj_desc->field.base_byte_offset,
518 				  obj_desc->field.access_byte_width,
519 				  obj_desc->field.region_obj));
520 		break;
521 
522 	case ACPI_TYPE_LOCAL_BANK_FIELD:
523 
524 		obj_desc->bank_field.value = info->bank_value;
525 		obj_desc->bank_field.region_obj =
526 		    acpi_ns_get_attached_object(info->region_node);
527 		obj_desc->bank_field.bank_obj =
528 		    acpi_ns_get_attached_object(info->register_node);
529 
530 		/* An additional reference for the attached objects */
531 
532 		acpi_ut_add_reference(obj_desc->bank_field.region_obj);
533 		acpi_ut_add_reference(obj_desc->bank_field.bank_obj);
534 
535 		ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
536 				  "Bank Field: BitOff %X, Off %X, Gran %X, Region %p, BankReg %p\n",
537 				  obj_desc->bank_field.start_field_bit_offset,
538 				  obj_desc->bank_field.base_byte_offset,
539 				  obj_desc->field.access_byte_width,
540 				  obj_desc->bank_field.region_obj,
541 				  obj_desc->bank_field.bank_obj));
542 
543 		/*
544 		 * Remember location in AML stream of the field unit
545 		 * opcode and operands -- since the bank_value
546 		 * operands must be evaluated.
547 		 */
548 		second_desc = obj_desc->common.next_object;
549 		second_desc->extra.aml_start =
550 		    ACPI_CAST_PTR(union acpi_parse_object,
551 				  info->data_register_node)->named.data;
552 		second_desc->extra.aml_length =
553 		    ACPI_CAST_PTR(union acpi_parse_object,
554 				  info->data_register_node)->named.length;
555 
556 		break;
557 
558 	case ACPI_TYPE_LOCAL_INDEX_FIELD:
559 
560 		/* Get the Index and Data registers */
561 
562 		obj_desc->index_field.index_obj =
563 		    acpi_ns_get_attached_object(info->register_node);
564 		obj_desc->index_field.data_obj =
565 		    acpi_ns_get_attached_object(info->data_register_node);
566 
567 		if (!obj_desc->index_field.data_obj
568 		    || !obj_desc->index_field.index_obj) {
569 			ACPI_ERROR((AE_INFO,
570 				    "Null Index Object during field prep"));
571 			acpi_ut_delete_object_desc(obj_desc);
572 			return_ACPI_STATUS(AE_AML_INTERNAL);
573 		}
574 
575 		/* An additional reference for the attached objects */
576 
577 		acpi_ut_add_reference(obj_desc->index_field.data_obj);
578 		acpi_ut_add_reference(obj_desc->index_field.index_obj);
579 
580 		/*
581 		 * April 2006: Changed to match MS behavior
582 		 *
583 		 * The value written to the Index register is the byte offset of the
584 		 * target field in units of the granularity of the index_field
585 		 *
586 		 * Previously, the value was calculated as an index in terms of the
587 		 * width of the Data register, as below:
588 		 *
589 		 *      obj_desc->index_field.Value = (u32)
590 		 *          (Info->field_bit_position / ACPI_MUL_8 (
591 		 *              obj_desc->Field.access_byte_width));
592 		 *
593 		 * February 2006: Tried value as a byte offset:
594 		 *      obj_desc->index_field.Value = (u32)
595 		 *          ACPI_DIV_8 (Info->field_bit_position);
596 		 */
597 		obj_desc->index_field.value =
598 		    (u32) ACPI_ROUND_DOWN(ACPI_DIV_8(info->field_bit_position),
599 					  obj_desc->index_field.
600 					  access_byte_width);
601 
602 		ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
603 				  "IndexField: BitOff %X, Off %X, Value %X, "
604 				  "Gran %X, Index %p, Data %p\n",
605 				  obj_desc->index_field.start_field_bit_offset,
606 				  obj_desc->index_field.base_byte_offset,
607 				  obj_desc->index_field.value,
608 				  obj_desc->field.access_byte_width,
609 				  obj_desc->index_field.index_obj,
610 				  obj_desc->index_field.data_obj));
611 		break;
612 
613 	default:
614 
615 		/* No other types should get here */
616 
617 		break;
618 	}
619 
620 	/*
621 	 * Store the constructed descriptor (obj_desc) into the parent Node,
622 	 * preserving the current type of that named_obj.
623 	 */
624 	status =
625 	    acpi_ns_attach_object(info->field_node, obj_desc,
626 				  acpi_ns_get_type(info->field_node));
627 
628 	ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
629 			  "Set NamedObj %p [%4.4s], ObjDesc %p\n",
630 			  info->field_node,
631 			  acpi_ut_get_node_name(info->field_node), obj_desc));
632 
633 	/* Remove local reference to the object */
634 
635 	acpi_ut_remove_reference(obj_desc);
636 	return_ACPI_STATUS(status);
637 }
638