xref: /openbmc/linux/drivers/acpi/acpica/rscalc.c (revision 4f6cce39)
1 /*******************************************************************************
2  *
3  * Module Name: rscalc - Calculate stream and list lengths
4  *
5  ******************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2017, 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 "acresrc.h"
47 #include "acnamesp.h"
48 
49 #define _COMPONENT          ACPI_RESOURCES
50 ACPI_MODULE_NAME("rscalc")
51 
52 /* Local prototypes */
53 static u8 acpi_rs_count_set_bits(u16 bit_field);
54 
55 static acpi_rs_length
56 acpi_rs_struct_option_length(struct acpi_resource_source *resource_source);
57 
58 static u32
59 acpi_rs_stream_option_length(u32 resource_length, u32 minimum_total_length);
60 
61 /*******************************************************************************
62  *
63  * FUNCTION:    acpi_rs_count_set_bits
64  *
65  * PARAMETERS:  bit_field       - Field in which to count bits
66  *
67  * RETURN:      Number of bits set within the field
68  *
69  * DESCRIPTION: Count the number of bits set in a resource field. Used for
70  *              (Short descriptor) interrupt and DMA lists.
71  *
72  ******************************************************************************/
73 
74 static u8 acpi_rs_count_set_bits(u16 bit_field)
75 {
76 	u8 bits_set;
77 
78 	ACPI_FUNCTION_ENTRY();
79 
80 	for (bits_set = 0; bit_field; bits_set++) {
81 
82 		/* Zero the least significant bit that is set */
83 
84 		bit_field &= (u16) (bit_field - 1);
85 	}
86 
87 	return (bits_set);
88 }
89 
90 /*******************************************************************************
91  *
92  * FUNCTION:    acpi_rs_struct_option_length
93  *
94  * PARAMETERS:  resource_source     - Pointer to optional descriptor field
95  *
96  * RETURN:      Status
97  *
98  * DESCRIPTION: Common code to handle optional resource_source_index and
99  *              resource_source fields in some Large descriptors. Used during
100  *              list-to-stream conversion
101  *
102  ******************************************************************************/
103 
104 static acpi_rs_length
105 acpi_rs_struct_option_length(struct acpi_resource_source *resource_source)
106 {
107 	ACPI_FUNCTION_ENTRY();
108 
109 	/*
110 	 * If the resource_source string is valid, return the size of the string
111 	 * (string_length includes the NULL terminator) plus the size of the
112 	 * resource_source_index (1).
113 	 */
114 	if (resource_source->string_ptr) {
115 		return ((acpi_rs_length)(resource_source->string_length + 1));
116 	}
117 
118 	return (0);
119 }
120 
121 /*******************************************************************************
122  *
123  * FUNCTION:    acpi_rs_stream_option_length
124  *
125  * PARAMETERS:  resource_length     - Length from the resource header
126  *              minimum_total_length - Minimum length of this resource, before
127  *                                    any optional fields. Includes header size
128  *
129  * RETURN:      Length of optional string (0 if no string present)
130  *
131  * DESCRIPTION: Common code to handle optional resource_source_index and
132  *              resource_source fields in some Large descriptors. Used during
133  *              stream-to-list conversion
134  *
135  ******************************************************************************/
136 
137 static u32
138 acpi_rs_stream_option_length(u32 resource_length,
139 			     u32 minimum_aml_resource_length)
140 {
141 	u32 string_length = 0;
142 
143 	ACPI_FUNCTION_ENTRY();
144 
145 	/*
146 	 * The resource_source_index and resource_source are optional elements of
147 	 * some Large-type resource descriptors.
148 	 */
149 
150 	/*
151 	 * If the length of the actual resource descriptor is greater than the
152 	 * ACPI spec-defined minimum length, it means that a resource_source_index
153 	 * exists and is followed by a (required) null terminated string. The
154 	 * string length (including the null terminator) is the resource length
155 	 * minus the minimum length, minus one byte for the resource_source_index
156 	 * itself.
157 	 */
158 	if (resource_length > minimum_aml_resource_length) {
159 
160 		/* Compute the length of the optional string */
161 
162 		string_length =
163 		    resource_length - minimum_aml_resource_length - 1;
164 	}
165 
166 	/*
167 	 * Round the length up to a multiple of the native word in order to
168 	 * guarantee that the entire resource descriptor is native word aligned
169 	 */
170 	return ((u32) ACPI_ROUND_UP_TO_NATIVE_WORD(string_length));
171 }
172 
173 /*******************************************************************************
174  *
175  * FUNCTION:    acpi_rs_get_aml_length
176  *
177  * PARAMETERS:  resource            - Pointer to the resource linked list
178  *              resource_list_size  - Size of the resource linked list
179  *              size_needed         - Where the required size is returned
180  *
181  * RETURN:      Status
182  *
183  * DESCRIPTION: Takes a linked list of internal resource descriptors and
184  *              calculates the size buffer needed to hold the corresponding
185  *              external resource byte stream.
186  *
187  ******************************************************************************/
188 
189 acpi_status
190 acpi_rs_get_aml_length(struct acpi_resource *resource,
191 		       acpi_size resource_list_size, acpi_size *size_needed)
192 {
193 	acpi_size aml_size_needed = 0;
194 	struct acpi_resource *resource_end;
195 	acpi_rs_length total_size;
196 
197 	ACPI_FUNCTION_TRACE(rs_get_aml_length);
198 
199 	/* Traverse entire list of internal resource descriptors */
200 
201 	resource_end =
202 	    ACPI_ADD_PTR(struct acpi_resource, resource, resource_list_size);
203 	while (resource < resource_end) {
204 
205 		/* Validate the descriptor type */
206 
207 		if (resource->type > ACPI_RESOURCE_TYPE_MAX) {
208 			return_ACPI_STATUS(AE_AML_INVALID_RESOURCE_TYPE);
209 		}
210 
211 		/* Sanity check the length. It must not be zero, or we loop forever */
212 
213 		if (!resource->length) {
214 			return_ACPI_STATUS(AE_AML_BAD_RESOURCE_LENGTH);
215 		}
216 
217 		/* Get the base size of the (external stream) resource descriptor */
218 
219 		total_size = acpi_gbl_aml_resource_sizes[resource->type];
220 
221 		/*
222 		 * Augment the base size for descriptors with optional and/or
223 		 * variable-length fields
224 		 */
225 		switch (resource->type) {
226 		case ACPI_RESOURCE_TYPE_IRQ:
227 
228 			/* Length can be 3 or 2 */
229 
230 			if (resource->data.irq.descriptor_length == 2) {
231 				total_size--;
232 			}
233 			break;
234 
235 		case ACPI_RESOURCE_TYPE_START_DEPENDENT:
236 
237 			/* Length can be 1 or 0 */
238 
239 			if (resource->data.irq.descriptor_length == 0) {
240 				total_size--;
241 			}
242 			break;
243 
244 		case ACPI_RESOURCE_TYPE_VENDOR:
245 			/*
246 			 * Vendor Defined Resource:
247 			 * For a Vendor Specific resource, if the Length is between 1 and 7
248 			 * it will be created as a Small Resource data type, otherwise it
249 			 * is a Large Resource data type.
250 			 */
251 			if (resource->data.vendor.byte_length > 7) {
252 
253 				/* Base size of a Large resource descriptor */
254 
255 				total_size =
256 				    sizeof(struct aml_resource_large_header);
257 			}
258 
259 			/* Add the size of the vendor-specific data */
260 
261 			total_size = (acpi_rs_length)
262 			    (total_size + resource->data.vendor.byte_length);
263 			break;
264 
265 		case ACPI_RESOURCE_TYPE_END_TAG:
266 			/*
267 			 * End Tag:
268 			 * We are done -- return the accumulated total size.
269 			 */
270 			*size_needed = aml_size_needed + total_size;
271 
272 			/* Normal exit */
273 
274 			return_ACPI_STATUS(AE_OK);
275 
276 		case ACPI_RESOURCE_TYPE_ADDRESS16:
277 			/*
278 			 * 16-Bit Address Resource:
279 			 * Add the size of the optional resource_source info
280 			 */
281 			total_size = (acpi_rs_length)(total_size +
282 						      acpi_rs_struct_option_length
283 						      (&resource->data.
284 						       address16.
285 						       resource_source));
286 			break;
287 
288 		case ACPI_RESOURCE_TYPE_ADDRESS32:
289 			/*
290 			 * 32-Bit Address Resource:
291 			 * Add the size of the optional resource_source info
292 			 */
293 			total_size = (acpi_rs_length)(total_size +
294 						      acpi_rs_struct_option_length
295 						      (&resource->data.
296 						       address32.
297 						       resource_source));
298 			break;
299 
300 		case ACPI_RESOURCE_TYPE_ADDRESS64:
301 			/*
302 			 * 64-Bit Address Resource:
303 			 * Add the size of the optional resource_source info
304 			 */
305 			total_size = (acpi_rs_length)(total_size +
306 						      acpi_rs_struct_option_length
307 						      (&resource->data.
308 						       address64.
309 						       resource_source));
310 			break;
311 
312 		case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
313 			/*
314 			 * Extended IRQ Resource:
315 			 * Add the size of each additional optional interrupt beyond the
316 			 * required 1 (4 bytes for each u32 interrupt number)
317 			 */
318 			total_size = (acpi_rs_length)(total_size +
319 						      ((resource->data.
320 							extended_irq.
321 							interrupt_count -
322 							1) * 4) +
323 						      /* Add the size of the optional resource_source info */
324 						      acpi_rs_struct_option_length
325 						      (&resource->data.
326 						       extended_irq.
327 						       resource_source));
328 			break;
329 
330 		case ACPI_RESOURCE_TYPE_GPIO:
331 
332 			total_size = (acpi_rs_length)(total_size +
333 						      (resource->data.gpio.
334 						       pin_table_length * 2) +
335 						      resource->data.gpio.
336 						      resource_source.
337 						      string_length +
338 						      resource->data.gpio.
339 						      vendor_length);
340 
341 			break;
342 
343 		case ACPI_RESOURCE_TYPE_SERIAL_BUS:
344 
345 			total_size =
346 			    acpi_gbl_aml_resource_serial_bus_sizes[resource->
347 								   data.
348 								   common_serial_bus.
349 								   type];
350 
351 			total_size = (acpi_rs_length)(total_size +
352 						      resource->data.
353 						      i2c_serial_bus.
354 						      resource_source.
355 						      string_length +
356 						      resource->data.
357 						      i2c_serial_bus.
358 						      vendor_length);
359 
360 			break;
361 
362 		default:
363 
364 			break;
365 		}
366 
367 		/* Update the total */
368 
369 		aml_size_needed += total_size;
370 
371 		/* Point to the next object */
372 
373 		resource =
374 		    ACPI_ADD_PTR(struct acpi_resource, resource,
375 				 resource->length);
376 	}
377 
378 	/* Did not find an end_tag resource descriptor */
379 
380 	return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
381 }
382 
383 /*******************************************************************************
384  *
385  * FUNCTION:    acpi_rs_get_list_length
386  *
387  * PARAMETERS:  aml_buffer          - Pointer to the resource byte stream
388  *              aml_buffer_length   - Size of aml_buffer
389  *              size_needed         - Where the size needed is returned
390  *
391  * RETURN:      Status
392  *
393  * DESCRIPTION: Takes an external resource byte stream and calculates the size
394  *              buffer needed to hold the corresponding internal resource
395  *              descriptor linked list.
396  *
397  ******************************************************************************/
398 
399 acpi_status
400 acpi_rs_get_list_length(u8 *aml_buffer,
401 			u32 aml_buffer_length, acpi_size *size_needed)
402 {
403 	acpi_status status;
404 	u8 *end_aml;
405 	u8 *buffer;
406 	u32 buffer_size;
407 	u16 temp16;
408 	u16 resource_length;
409 	u32 extra_struct_bytes;
410 	u8 resource_index;
411 	u8 minimum_aml_resource_length;
412 	union aml_resource *aml_resource;
413 
414 	ACPI_FUNCTION_TRACE(rs_get_list_length);
415 
416 	*size_needed = ACPI_RS_SIZE_MIN;	/* Minimum size is one end_tag */
417 	end_aml = aml_buffer + aml_buffer_length;
418 
419 	/* Walk the list of AML resource descriptors */
420 
421 	while (aml_buffer < end_aml) {
422 
423 		/* Validate the Resource Type and Resource Length */
424 
425 		status =
426 		    acpi_ut_validate_resource(NULL, aml_buffer,
427 					      &resource_index);
428 		if (ACPI_FAILURE(status)) {
429 			/*
430 			 * Exit on failure. Cannot continue because the descriptor length
431 			 * may be bogus also.
432 			 */
433 			return_ACPI_STATUS(status);
434 		}
435 
436 		aml_resource = (void *)aml_buffer;
437 
438 		/* Get the resource length and base (minimum) AML size */
439 
440 		resource_length = acpi_ut_get_resource_length(aml_buffer);
441 		minimum_aml_resource_length =
442 		    acpi_gbl_resource_aml_sizes[resource_index];
443 
444 		/*
445 		 * Augment the size for descriptors with optional
446 		 * and/or variable length fields
447 		 */
448 		extra_struct_bytes = 0;
449 		buffer =
450 		    aml_buffer + acpi_ut_get_resource_header_length(aml_buffer);
451 
452 		switch (acpi_ut_get_resource_type(aml_buffer)) {
453 		case ACPI_RESOURCE_NAME_IRQ:
454 			/*
455 			 * IRQ Resource:
456 			 * Get the number of bits set in the 16-bit IRQ mask
457 			 */
458 			ACPI_MOVE_16_TO_16(&temp16, buffer);
459 			extra_struct_bytes = acpi_rs_count_set_bits(temp16);
460 			break;
461 
462 		case ACPI_RESOURCE_NAME_DMA:
463 			/*
464 			 * DMA Resource:
465 			 * Get the number of bits set in the 8-bit DMA mask
466 			 */
467 			extra_struct_bytes = acpi_rs_count_set_bits(*buffer);
468 			break;
469 
470 		case ACPI_RESOURCE_NAME_VENDOR_SMALL:
471 		case ACPI_RESOURCE_NAME_VENDOR_LARGE:
472 			/*
473 			 * Vendor Resource:
474 			 * Get the number of vendor data bytes
475 			 */
476 			extra_struct_bytes = resource_length;
477 
478 			/*
479 			 * There is already one byte included in the minimum
480 			 * descriptor size. If there are extra struct bytes,
481 			 * subtract one from the count.
482 			 */
483 			if (extra_struct_bytes) {
484 				extra_struct_bytes--;
485 			}
486 			break;
487 
488 		case ACPI_RESOURCE_NAME_END_TAG:
489 			/*
490 			 * End Tag: This is the normal exit
491 			 */
492 			return_ACPI_STATUS(AE_OK);
493 
494 		case ACPI_RESOURCE_NAME_ADDRESS32:
495 		case ACPI_RESOURCE_NAME_ADDRESS16:
496 		case ACPI_RESOURCE_NAME_ADDRESS64:
497 			/*
498 			 * Address Resource:
499 			 * Add the size of the optional resource_source
500 			 */
501 			extra_struct_bytes =
502 			    acpi_rs_stream_option_length(resource_length,
503 							 minimum_aml_resource_length);
504 			break;
505 
506 		case ACPI_RESOURCE_NAME_EXTENDED_IRQ:
507 			/*
508 			 * Extended IRQ Resource:
509 			 * Using the interrupt_table_length, add 4 bytes for each additional
510 			 * interrupt. Note: at least one interrupt is required and is
511 			 * included in the minimum descriptor size (reason for the -1)
512 			 */
513 			extra_struct_bytes = (buffer[1] - 1) * sizeof(u32);
514 
515 			/* Add the size of the optional resource_source */
516 
517 			extra_struct_bytes +=
518 			    acpi_rs_stream_option_length(resource_length -
519 							 extra_struct_bytes,
520 							 minimum_aml_resource_length);
521 			break;
522 
523 		case ACPI_RESOURCE_NAME_GPIO:
524 
525 			/* Vendor data is optional */
526 
527 			if (aml_resource->gpio.vendor_length) {
528 				extra_struct_bytes +=
529 				    aml_resource->gpio.vendor_offset -
530 				    aml_resource->gpio.pin_table_offset +
531 				    aml_resource->gpio.vendor_length;
532 			} else {
533 				extra_struct_bytes +=
534 				    aml_resource->large_header.resource_length +
535 				    sizeof(struct aml_resource_large_header) -
536 				    aml_resource->gpio.pin_table_offset;
537 			}
538 			break;
539 
540 		case ACPI_RESOURCE_NAME_SERIAL_BUS:
541 
542 			minimum_aml_resource_length =
543 			    acpi_gbl_resource_aml_serial_bus_sizes
544 			    [aml_resource->common_serial_bus.type];
545 			extra_struct_bytes +=
546 			    aml_resource->common_serial_bus.resource_length -
547 			    minimum_aml_resource_length;
548 			break;
549 
550 		default:
551 
552 			break;
553 		}
554 
555 		/*
556 		 * Update the required buffer size for the internal descriptor structs
557 		 *
558 		 * Important: Round the size up for the appropriate alignment. This
559 		 * is a requirement on IA64.
560 		 */
561 		if (acpi_ut_get_resource_type(aml_buffer) ==
562 		    ACPI_RESOURCE_NAME_SERIAL_BUS) {
563 			buffer_size =
564 			    acpi_gbl_resource_struct_serial_bus_sizes
565 			    [aml_resource->common_serial_bus.type] +
566 			    extra_struct_bytes;
567 		} else {
568 			buffer_size =
569 			    acpi_gbl_resource_struct_sizes[resource_index] +
570 			    extra_struct_bytes;
571 		}
572 
573 		buffer_size = (u32)ACPI_ROUND_UP_TO_NATIVE_WORD(buffer_size);
574 		*size_needed += buffer_size;
575 
576 		ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES,
577 				  "Type %.2X, AmlLength %.2X InternalLength %.2X\n",
578 				  acpi_ut_get_resource_type(aml_buffer),
579 				  acpi_ut_get_descriptor_length(aml_buffer),
580 				  buffer_size));
581 
582 		/*
583 		 * Point to the next resource within the AML stream using the length
584 		 * contained in the resource descriptor header
585 		 */
586 		aml_buffer += acpi_ut_get_descriptor_length(aml_buffer);
587 	}
588 
589 	/* Did not find an end_tag resource descriptor */
590 
591 	return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
592 }
593 
594 /*******************************************************************************
595  *
596  * FUNCTION:    acpi_rs_get_pci_routing_table_length
597  *
598  * PARAMETERS:  package_object          - Pointer to the package object
599  *              buffer_size_needed      - u32 pointer of the size buffer
600  *                                        needed to properly return the
601  *                                        parsed data
602  *
603  * RETURN:      Status
604  *
605  * DESCRIPTION: Given a package representing a PCI routing table, this
606  *              calculates the size of the corresponding linked list of
607  *              descriptions.
608  *
609  ******************************************************************************/
610 
611 acpi_status
612 acpi_rs_get_pci_routing_table_length(union acpi_operand_object *package_object,
613 				     acpi_size *buffer_size_needed)
614 {
615 	u32 number_of_elements;
616 	acpi_size temp_size_needed = 0;
617 	union acpi_operand_object **top_object_list;
618 	u32 index;
619 	union acpi_operand_object *package_element;
620 	union acpi_operand_object **sub_object_list;
621 	u8 name_found;
622 	u32 table_index;
623 
624 	ACPI_FUNCTION_TRACE(rs_get_pci_routing_table_length);
625 
626 	number_of_elements = package_object->package.count;
627 
628 	/*
629 	 * Calculate the size of the return buffer.
630 	 * The base size is the number of elements * the sizes of the
631 	 * structures. Additional space for the strings is added below.
632 	 * The minus one is to subtract the size of the u8 Source[1]
633 	 * member because it is added below.
634 	 *
635 	 * But each PRT_ENTRY structure has a pointer to a string and
636 	 * the size of that string must be found.
637 	 */
638 	top_object_list = package_object->package.elements;
639 
640 	for (index = 0; index < number_of_elements; index++) {
641 
642 		/* Dereference the subpackage */
643 
644 		package_element = *top_object_list;
645 
646 		/* We must have a valid Package object */
647 
648 		if (!package_element ||
649 		    (package_element->common.type != ACPI_TYPE_PACKAGE)) {
650 			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
651 		}
652 
653 		/*
654 		 * The sub_object_list will now point to an array of the
655 		 * four IRQ elements: Address, Pin, Source and source_index
656 		 */
657 		sub_object_list = package_element->package.elements;
658 
659 		/* Scan the irq_table_elements for the Source Name String */
660 
661 		name_found = FALSE;
662 
663 		for (table_index = 0;
664 		     table_index < package_element->package.count
665 		     && !name_found; table_index++) {
666 			if (*sub_object_list &&	/* Null object allowed */
667 			    ((ACPI_TYPE_STRING ==
668 			      (*sub_object_list)->common.type) ||
669 			     ((ACPI_TYPE_LOCAL_REFERENCE ==
670 			       (*sub_object_list)->common.type) &&
671 			      ((*sub_object_list)->reference.class ==
672 			       ACPI_REFCLASS_NAME)))) {
673 				name_found = TRUE;
674 			} else {
675 				/* Look at the next element */
676 
677 				sub_object_list++;
678 			}
679 		}
680 
681 		temp_size_needed += (sizeof(struct acpi_pci_routing_table) - 4);
682 
683 		/* Was a String type found? */
684 
685 		if (name_found) {
686 			if ((*sub_object_list)->common.type == ACPI_TYPE_STRING) {
687 				/*
688 				 * The length String.Length field does not include the
689 				 * terminating NULL, add 1
690 				 */
691 				temp_size_needed += ((acpi_size)
692 						     (*sub_object_list)->string.
693 						     length + 1);
694 			} else {
695 				temp_size_needed += acpi_ns_get_pathname_length((*sub_object_list)->reference.node);
696 			}
697 		} else {
698 			/*
699 			 * If no name was found, then this is a NULL, which is
700 			 * translated as a u32 zero.
701 			 */
702 			temp_size_needed += sizeof(u32);
703 		}
704 
705 		/* Round up the size since each element must be aligned */
706 
707 		temp_size_needed = ACPI_ROUND_UP_TO_64BIT(temp_size_needed);
708 
709 		/* Point to the next union acpi_operand_object */
710 
711 		top_object_list++;
712 	}
713 
714 	/*
715 	 * Add an extra element to the end of the list, essentially a
716 	 * NULL terminator
717 	 */
718 	*buffer_size_needed =
719 	    temp_size_needed + sizeof(struct acpi_pci_routing_table);
720 	return_ACPI_STATUS(AE_OK);
721 }
722