xref: /openbmc/linux/drivers/acpi/acpica/rsutils.c (revision b627b4ed)
1 /*******************************************************************************
2  *
3  * Module Name: rsutils - Utilities for the resource manager
4  *
5  ******************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2008, 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 "acnamesp.h"
47 #include "acresrc.h"
48 
49 #define _COMPONENT          ACPI_RESOURCES
50 ACPI_MODULE_NAME("rsutils")
51 
52 /*******************************************************************************
53  *
54  * FUNCTION:    acpi_rs_decode_bitmask
55  *
56  * PARAMETERS:  Mask            - Bitmask to decode
57  *              List            - Where the converted list is returned
58  *
59  * RETURN:      Count of bits set (length of list)
60  *
61  * DESCRIPTION: Convert a bit mask into a list of values
62  *
63  ******************************************************************************/
64 u8 acpi_rs_decode_bitmask(u16 mask, u8 * list)
65 {
66 	u8 i;
67 	u8 bit_count;
68 
69 	ACPI_FUNCTION_ENTRY();
70 
71 	/* Decode the mask bits */
72 
73 	for (i = 0, bit_count = 0; mask; i++) {
74 		if (mask & 0x0001) {
75 			list[bit_count] = i;
76 			bit_count++;
77 		}
78 
79 		mask >>= 1;
80 	}
81 
82 	return (bit_count);
83 }
84 
85 /*******************************************************************************
86  *
87  * FUNCTION:    acpi_rs_encode_bitmask
88  *
89  * PARAMETERS:  List            - List of values to encode
90  *              Count           - Length of list
91  *
92  * RETURN:      Encoded bitmask
93  *
94  * DESCRIPTION: Convert a list of values to an encoded bitmask
95  *
96  ******************************************************************************/
97 
98 u16 acpi_rs_encode_bitmask(u8 * list, u8 count)
99 {
100 	u32 i;
101 	u16 mask;
102 
103 	ACPI_FUNCTION_ENTRY();
104 
105 	/* Encode the list into a single bitmask */
106 
107 	for (i = 0, mask = 0; i < count; i++) {
108 		mask |= (0x1 << list[i]);
109 	}
110 
111 	return mask;
112 }
113 
114 /*******************************************************************************
115  *
116  * FUNCTION:    acpi_rs_move_data
117  *
118  * PARAMETERS:  Destination         - Pointer to the destination descriptor
119  *              Source              - Pointer to the source descriptor
120  *              item_count          - How many items to move
121  *              move_type           - Byte width
122  *
123  * RETURN:      None
124  *
125  * DESCRIPTION: Move multiple data items from one descriptor to another. Handles
126  *              alignment issues and endian issues if necessary, as configured
127  *              via the ACPI_MOVE_* macros. (This is why a memcpy is not used)
128  *
129  ******************************************************************************/
130 
131 void
132 acpi_rs_move_data(void *destination, void *source, u16 item_count, u8 move_type)
133 {
134 	u32 i;
135 
136 	ACPI_FUNCTION_ENTRY();
137 
138 	/* One move per item */
139 
140 	for (i = 0; i < item_count; i++) {
141 		switch (move_type) {
142 			/*
143 			 * For the 8-bit case, we can perform the move all at once
144 			 * since there are no alignment or endian issues
145 			 */
146 		case ACPI_RSC_MOVE8:
147 			ACPI_MEMCPY(destination, source, item_count);
148 			return;
149 
150 			/*
151 			 * 16-, 32-, and 64-bit cases must use the move macros that perform
152 			 * endian conversion and/or accomodate hardware that cannot perform
153 			 * misaligned memory transfers
154 			 */
155 		case ACPI_RSC_MOVE16:
156 			ACPI_MOVE_16_TO_16(&ACPI_CAST_PTR(u16, destination)[i],
157 					   &ACPI_CAST_PTR(u16, source)[i]);
158 			break;
159 
160 		case ACPI_RSC_MOVE32:
161 			ACPI_MOVE_32_TO_32(&ACPI_CAST_PTR(u32, destination)[i],
162 					   &ACPI_CAST_PTR(u32, source)[i]);
163 			break;
164 
165 		case ACPI_RSC_MOVE64:
166 			ACPI_MOVE_64_TO_64(&ACPI_CAST_PTR(u64, destination)[i],
167 					   &ACPI_CAST_PTR(u64, source)[i]);
168 			break;
169 
170 		default:
171 			return;
172 		}
173 	}
174 }
175 
176 /*******************************************************************************
177  *
178  * FUNCTION:    acpi_rs_set_resource_length
179  *
180  * PARAMETERS:  total_length        - Length of the AML descriptor, including
181  *                                    the header and length fields.
182  *              Aml                 - Pointer to the raw AML descriptor
183  *
184  * RETURN:      None
185  *
186  * DESCRIPTION: Set the resource_length field of an AML
187  *              resource descriptor, both Large and Small descriptors are
188  *              supported automatically. Note: Descriptor Type field must
189  *              be valid.
190  *
191  ******************************************************************************/
192 
193 void
194 acpi_rs_set_resource_length(acpi_rsdesc_size total_length,
195 			    union aml_resource *aml)
196 {
197 	acpi_rs_length resource_length;
198 
199 	ACPI_FUNCTION_ENTRY();
200 
201 	/* Length is the total descriptor length minus the header length */
202 
203 	resource_length = (acpi_rs_length)
204 	    (total_length - acpi_ut_get_resource_header_length(aml));
205 
206 	/* Length is stored differently for large and small descriptors */
207 
208 	if (aml->small_header.descriptor_type & ACPI_RESOURCE_NAME_LARGE) {
209 
210 		/* Large descriptor -- bytes 1-2 contain the 16-bit length */
211 
212 		ACPI_MOVE_16_TO_16(&aml->large_header.resource_length,
213 				   &resource_length);
214 	} else {
215 		/* Small descriptor -- bits 2:0 of byte 0 contain the length */
216 
217 		aml->small_header.descriptor_type = (u8)
218 
219 		    /* Clear any existing length, preserving descriptor type bits */
220 		    ((aml->small_header.
221 		      descriptor_type & ~ACPI_RESOURCE_NAME_SMALL_LENGTH_MASK)
222 
223 		     | resource_length);
224 	}
225 }
226 
227 /*******************************************************************************
228  *
229  * FUNCTION:    acpi_rs_set_resource_header
230  *
231  * PARAMETERS:  descriptor_type     - Byte to be inserted as the type
232  *              total_length        - Length of the AML descriptor, including
233  *                                    the header and length fields.
234  *              Aml                 - Pointer to the raw AML descriptor
235  *
236  * RETURN:      None
237  *
238  * DESCRIPTION: Set the descriptor_type and resource_length fields of an AML
239  *              resource descriptor, both Large and Small descriptors are
240  *              supported automatically
241  *
242  ******************************************************************************/
243 
244 void
245 acpi_rs_set_resource_header(u8 descriptor_type,
246 			    acpi_rsdesc_size total_length,
247 			    union aml_resource *aml)
248 {
249 	ACPI_FUNCTION_ENTRY();
250 
251 	/* Set the Resource Type */
252 
253 	aml->small_header.descriptor_type = descriptor_type;
254 
255 	/* Set the Resource Length */
256 
257 	acpi_rs_set_resource_length(total_length, aml);
258 }
259 
260 /*******************************************************************************
261  *
262  * FUNCTION:    acpi_rs_strcpy
263  *
264  * PARAMETERS:  Destination         - Pointer to the destination string
265  *              Source              - Pointer to the source string
266  *
267  * RETURN:      String length, including NULL terminator
268  *
269  * DESCRIPTION: Local string copy that returns the string length, saving a
270  *              strcpy followed by a strlen.
271  *
272  ******************************************************************************/
273 
274 static u16 acpi_rs_strcpy(char *destination, char *source)
275 {
276 	u16 i;
277 
278 	ACPI_FUNCTION_ENTRY();
279 
280 	for (i = 0; source[i]; i++) {
281 		destination[i] = source[i];
282 	}
283 
284 	destination[i] = 0;
285 
286 	/* Return string length including the NULL terminator */
287 
288 	return ((u16) (i + 1));
289 }
290 
291 /*******************************************************************************
292  *
293  * FUNCTION:    acpi_rs_get_resource_source
294  *
295  * PARAMETERS:  resource_length     - Length field of the descriptor
296  *              minimum_length      - Minimum length of the descriptor (minus
297  *                                    any optional fields)
298  *              resource_source     - Where the resource_source is returned
299  *              Aml                 - Pointer to the raw AML descriptor
300  *              string_ptr          - (optional) where to store the actual
301  *                                    resource_source string
302  *
303  * RETURN:      Length of the string plus NULL terminator, rounded up to native
304  *              word boundary
305  *
306  * DESCRIPTION: Copy the optional resource_source data from a raw AML descriptor
307  *              to an internal resource descriptor
308  *
309  ******************************************************************************/
310 
311 acpi_rs_length
312 acpi_rs_get_resource_source(acpi_rs_length resource_length,
313 			    acpi_rs_length minimum_length,
314 			    struct acpi_resource_source * resource_source,
315 			    union aml_resource * aml, char *string_ptr)
316 {
317 	acpi_rsdesc_size total_length;
318 	u8 *aml_resource_source;
319 
320 	ACPI_FUNCTION_ENTRY();
321 
322 	total_length =
323 	    resource_length + sizeof(struct aml_resource_large_header);
324 	aml_resource_source = ACPI_ADD_PTR(u8, aml, minimum_length);
325 
326 	/*
327 	 * resource_source is present if the length of the descriptor is longer than
328 	 * the minimum length.
329 	 *
330 	 * Note: Some resource descriptors will have an additional null, so
331 	 * we add 1 to the minimum length.
332 	 */
333 	if (total_length > (acpi_rsdesc_size) (minimum_length + 1)) {
334 
335 		/* Get the resource_source_index */
336 
337 		resource_source->index = aml_resource_source[0];
338 
339 		resource_source->string_ptr = string_ptr;
340 		if (!string_ptr) {
341 			/*
342 			 * String destination pointer is not specified; Set the String
343 			 * pointer to the end of the current resource_source structure.
344 			 */
345 			resource_source->string_ptr =
346 			    ACPI_ADD_PTR(char, resource_source,
347 					 sizeof(struct acpi_resource_source));
348 		}
349 
350 		/*
351 		 * In order for the Resource length to be a multiple of the native
352 		 * word, calculate the length of the string (+1 for NULL terminator)
353 		 * and expand to the next word multiple.
354 		 *
355 		 * Zero the entire area of the buffer.
356 		 */
357 		total_length = (u32)
358 		ACPI_STRLEN(ACPI_CAST_PTR(char, &aml_resource_source[1])) + 1;
359 		total_length = (u32) ACPI_ROUND_UP_TO_NATIVE_WORD(total_length);
360 
361 		ACPI_MEMSET(resource_source->string_ptr, 0, total_length);
362 
363 		/* Copy the resource_source string to the destination */
364 
365 		resource_source->string_length =
366 		    acpi_rs_strcpy(resource_source->string_ptr,
367 				   ACPI_CAST_PTR(char,
368 						 &aml_resource_source[1]));
369 
370 		return ((acpi_rs_length) total_length);
371 	}
372 
373 	/* resource_source is not present */
374 
375 	resource_source->index = 0;
376 	resource_source->string_length = 0;
377 	resource_source->string_ptr = NULL;
378 	return (0);
379 }
380 
381 /*******************************************************************************
382  *
383  * FUNCTION:    acpi_rs_set_resource_source
384  *
385  * PARAMETERS:  Aml                 - Pointer to the raw AML descriptor
386  *              minimum_length      - Minimum length of the descriptor (minus
387  *                                    any optional fields)
388  *              resource_source     - Internal resource_source
389 
390  *
391  * RETURN:      Total length of the AML descriptor
392  *
393  * DESCRIPTION: Convert an optional resource_source from internal format to a
394  *              raw AML resource descriptor
395  *
396  ******************************************************************************/
397 
398 acpi_rsdesc_size
399 acpi_rs_set_resource_source(union aml_resource * aml,
400 			    acpi_rs_length minimum_length,
401 			    struct acpi_resource_source * resource_source)
402 {
403 	u8 *aml_resource_source;
404 	acpi_rsdesc_size descriptor_length;
405 
406 	ACPI_FUNCTION_ENTRY();
407 
408 	descriptor_length = minimum_length;
409 
410 	/* Non-zero string length indicates presence of a resource_source */
411 
412 	if (resource_source->string_length) {
413 
414 		/* Point to the end of the AML descriptor */
415 
416 		aml_resource_source = ACPI_ADD_PTR(u8, aml, minimum_length);
417 
418 		/* Copy the resource_source_index */
419 
420 		aml_resource_source[0] = (u8) resource_source->index;
421 
422 		/* Copy the resource_source string */
423 
424 		ACPI_STRCPY(ACPI_CAST_PTR(char, &aml_resource_source[1]),
425 			    resource_source->string_ptr);
426 
427 		/*
428 		 * Add the length of the string (+ 1 for null terminator) to the
429 		 * final descriptor length
430 		 */
431 		descriptor_length +=
432 		    ((acpi_rsdesc_size) resource_source->string_length + 1);
433 	}
434 
435 	/* Return the new total length of the AML descriptor */
436 
437 	return (descriptor_length);
438 }
439 
440 /*******************************************************************************
441  *
442  * FUNCTION:    acpi_rs_get_prt_method_data
443  *
444  * PARAMETERS:  Node            - Device node
445  *              ret_buffer      - Pointer to a buffer structure for the
446  *                                results
447  *
448  * RETURN:      Status
449  *
450  * DESCRIPTION: This function is called to get the _PRT value of an object
451  *              contained in an object specified by the handle passed in
452  *
453  *              If the function fails an appropriate status will be returned
454  *              and the contents of the callers buffer is undefined.
455  *
456  ******************************************************************************/
457 
458 acpi_status
459 acpi_rs_get_prt_method_data(struct acpi_namespace_node * node,
460 			    struct acpi_buffer * ret_buffer)
461 {
462 	union acpi_operand_object *obj_desc;
463 	acpi_status status;
464 
465 	ACPI_FUNCTION_TRACE(rs_get_prt_method_data);
466 
467 	/* Parameters guaranteed valid by caller */
468 
469 	/* Execute the method, no parameters */
470 
471 	status = acpi_ut_evaluate_object(node, METHOD_NAME__PRT,
472 					 ACPI_BTYPE_PACKAGE, &obj_desc);
473 	if (ACPI_FAILURE(status)) {
474 		return_ACPI_STATUS(status);
475 	}
476 
477 	/*
478 	 * Create a resource linked list from the byte stream buffer that comes
479 	 * back from the _CRS method execution.
480 	 */
481 	status = acpi_rs_create_pci_routing_table(obj_desc, ret_buffer);
482 
483 	/* On exit, we must delete the object returned by evaluate_object */
484 
485 	acpi_ut_remove_reference(obj_desc);
486 	return_ACPI_STATUS(status);
487 }
488 
489 /*******************************************************************************
490  *
491  * FUNCTION:    acpi_rs_get_crs_method_data
492  *
493  * PARAMETERS:  Node            - Device node
494  *              ret_buffer      - Pointer to a buffer structure for the
495  *                                results
496  *
497  * RETURN:      Status
498  *
499  * DESCRIPTION: This function is called to get the _CRS value of an object
500  *              contained in an object specified by the handle passed in
501  *
502  *              If the function fails an appropriate status will be returned
503  *              and the contents of the callers buffer is undefined.
504  *
505  ******************************************************************************/
506 
507 acpi_status
508 acpi_rs_get_crs_method_data(struct acpi_namespace_node *node,
509 			    struct acpi_buffer *ret_buffer)
510 {
511 	union acpi_operand_object *obj_desc;
512 	acpi_status status;
513 
514 	ACPI_FUNCTION_TRACE(rs_get_crs_method_data);
515 
516 	/* Parameters guaranteed valid by caller */
517 
518 	/* Execute the method, no parameters */
519 
520 	status = acpi_ut_evaluate_object(node, METHOD_NAME__CRS,
521 					 ACPI_BTYPE_BUFFER, &obj_desc);
522 	if (ACPI_FAILURE(status)) {
523 		return_ACPI_STATUS(status);
524 	}
525 
526 	/*
527 	 * Make the call to create a resource linked list from the
528 	 * byte stream buffer that comes back from the _CRS method
529 	 * execution.
530 	 */
531 	status = acpi_rs_create_resource_list(obj_desc, ret_buffer);
532 
533 	/* On exit, we must delete the object returned by evaluate_object */
534 
535 	acpi_ut_remove_reference(obj_desc);
536 	return_ACPI_STATUS(status);
537 }
538 
539 /*******************************************************************************
540  *
541  * FUNCTION:    acpi_rs_get_prs_method_data
542  *
543  * PARAMETERS:  Node            - Device node
544  *              ret_buffer      - Pointer to a buffer structure for the
545  *                                results
546  *
547  * RETURN:      Status
548  *
549  * DESCRIPTION: This function is called to get the _PRS value of an object
550  *              contained in an object specified by the handle passed in
551  *
552  *              If the function fails an appropriate status will be returned
553  *              and the contents of the callers buffer is undefined.
554  *
555  ******************************************************************************/
556 
557 #ifdef ACPI_FUTURE_USAGE
558 acpi_status
559 acpi_rs_get_prs_method_data(struct acpi_namespace_node *node,
560 			    struct acpi_buffer *ret_buffer)
561 {
562 	union acpi_operand_object *obj_desc;
563 	acpi_status status;
564 
565 	ACPI_FUNCTION_TRACE(rs_get_prs_method_data);
566 
567 	/* Parameters guaranteed valid by caller */
568 
569 	/* Execute the method, no parameters */
570 
571 	status = acpi_ut_evaluate_object(node, METHOD_NAME__PRS,
572 					 ACPI_BTYPE_BUFFER, &obj_desc);
573 	if (ACPI_FAILURE(status)) {
574 		return_ACPI_STATUS(status);
575 	}
576 
577 	/*
578 	 * Make the call to create a resource linked list from the
579 	 * byte stream buffer that comes back from the _CRS method
580 	 * execution.
581 	 */
582 	status = acpi_rs_create_resource_list(obj_desc, ret_buffer);
583 
584 	/* On exit, we must delete the object returned by evaluate_object */
585 
586 	acpi_ut_remove_reference(obj_desc);
587 	return_ACPI_STATUS(status);
588 }
589 #endif				/*  ACPI_FUTURE_USAGE  */
590 
591 /*******************************************************************************
592  *
593  * FUNCTION:    acpi_rs_get_method_data
594  *
595  * PARAMETERS:  Handle          - Handle to the containing object
596  *              Path            - Path to method, relative to Handle
597  *              ret_buffer      - Pointer to a buffer structure for the
598  *                                results
599  *
600  * RETURN:      Status
601  *
602  * DESCRIPTION: This function is called to get the _CRS or _PRS value of an
603  *              object contained in an object specified by the handle passed in
604  *
605  *              If the function fails an appropriate status will be returned
606  *              and the contents of the callers buffer is undefined.
607  *
608  ******************************************************************************/
609 
610 acpi_status
611 acpi_rs_get_method_data(acpi_handle handle,
612 			char *path, struct acpi_buffer *ret_buffer)
613 {
614 	union acpi_operand_object *obj_desc;
615 	acpi_status status;
616 
617 	ACPI_FUNCTION_TRACE(rs_get_method_data);
618 
619 	/* Parameters guaranteed valid by caller */
620 
621 	/* Execute the method, no parameters */
622 
623 	status =
624 	    acpi_ut_evaluate_object(handle, path, ACPI_BTYPE_BUFFER, &obj_desc);
625 	if (ACPI_FAILURE(status)) {
626 		return_ACPI_STATUS(status);
627 	}
628 
629 	/*
630 	 * Make the call to create a resource linked list from the
631 	 * byte stream buffer that comes back from the method
632 	 * execution.
633 	 */
634 	status = acpi_rs_create_resource_list(obj_desc, ret_buffer);
635 
636 	/* On exit, we must delete the object returned by evaluate_object */
637 
638 	acpi_ut_remove_reference(obj_desc);
639 	return_ACPI_STATUS(status);
640 }
641 
642 /*******************************************************************************
643  *
644  * FUNCTION:    acpi_rs_set_srs_method_data
645  *
646  * PARAMETERS:  Node            - Device node
647  *              in_buffer       - Pointer to a buffer structure of the
648  *                                parameter
649  *
650  * RETURN:      Status
651  *
652  * DESCRIPTION: This function is called to set the _SRS of an object contained
653  *              in an object specified by the handle passed in
654  *
655  *              If the function fails an appropriate status will be returned
656  *              and the contents of the callers buffer is undefined.
657  *
658  * Note: Parameters guaranteed valid by caller
659  *
660  ******************************************************************************/
661 
662 acpi_status
663 acpi_rs_set_srs_method_data(struct acpi_namespace_node *node,
664 			    struct acpi_buffer *in_buffer)
665 {
666 	struct acpi_evaluate_info *info;
667 	union acpi_operand_object *args[2];
668 	acpi_status status;
669 	struct acpi_buffer buffer;
670 
671 	ACPI_FUNCTION_TRACE(rs_set_srs_method_data);
672 
673 	/* Allocate and initialize the evaluation information block */
674 
675 	info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
676 	if (!info) {
677 		return_ACPI_STATUS(AE_NO_MEMORY);
678 	}
679 
680 	info->prefix_node = node;
681 	info->pathname = METHOD_NAME__SRS;
682 	info->parameters = args;
683 	info->flags = ACPI_IGNORE_RETURN_VALUE;
684 
685 	/*
686 	 * The in_buffer parameter will point to a linked list of
687 	 * resource parameters. It needs to be formatted into a
688 	 * byte stream to be sent in as an input parameter to _SRS
689 	 *
690 	 * Convert the linked list into a byte stream
691 	 */
692 	buffer.length = ACPI_ALLOCATE_LOCAL_BUFFER;
693 	status = acpi_rs_create_aml_resources(in_buffer->pointer, &buffer);
694 	if (ACPI_FAILURE(status)) {
695 		goto cleanup;
696 	}
697 
698 	/* Create and initialize the method parameter object */
699 
700 	args[0] = acpi_ut_create_internal_object(ACPI_TYPE_BUFFER);
701 	if (!args[0]) {
702 		/*
703 		 * Must free the buffer allocated above (otherwise it is freed
704 		 * later)
705 		 */
706 		ACPI_FREE(buffer.pointer);
707 		status = AE_NO_MEMORY;
708 		goto cleanup;
709 	}
710 
711 	args[0]->buffer.length = (u32) buffer.length;
712 	args[0]->buffer.pointer = buffer.pointer;
713 	args[0]->common.flags = AOPOBJ_DATA_VALID;
714 	args[1] = NULL;
715 
716 	/* Execute the method, no return value is expected */
717 
718 	status = acpi_ns_evaluate(info);
719 
720 	/* Clean up and return the status from acpi_ns_evaluate */
721 
722 	acpi_ut_remove_reference(args[0]);
723 
724       cleanup:
725 	ACPI_FREE(info);
726 	return_ACPI_STATUS(status);
727 }
728