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
acpi_rs_count_set_bits(u16 bit_field)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
acpi_rs_struct_option_length(struct acpi_resource_source * resource_source)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
acpi_rs_stream_option_length(u32 resource_length,u32 minimum_aml_resource_length)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
acpi_rs_get_aml_length(struct acpi_resource * resource,acpi_size resource_list_size,acpi_size * size_needed)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_PIN_FUNCTION:
344
345 total_size = (acpi_rs_length)(total_size +
346 (resource->data.
347 pin_function.
348 pin_table_length * 2) +
349 resource->data.
350 pin_function.
351 resource_source.
352 string_length +
353 resource->data.
354 pin_function.
355 vendor_length);
356
357 break;
358
359 case ACPI_RESOURCE_TYPE_SERIAL_BUS:
360
361 total_size =
362 acpi_gbl_aml_resource_serial_bus_sizes[resource->
363 data.
364 common_serial_bus.
365 type];
366
367 total_size = (acpi_rs_length)(total_size +
368 resource->data.
369 i2c_serial_bus.
370 resource_source.
371 string_length +
372 resource->data.
373 i2c_serial_bus.
374 vendor_length);
375
376 break;
377
378 case ACPI_RESOURCE_TYPE_PIN_CONFIG:
379
380 total_size = (acpi_rs_length)(total_size +
381 (resource->data.
382 pin_config.
383 pin_table_length * 2) +
384 resource->data.pin_config.
385 resource_source.
386 string_length +
387 resource->data.pin_config.
388 vendor_length);
389
390 break;
391
392 case ACPI_RESOURCE_TYPE_PIN_GROUP:
393
394 total_size = (acpi_rs_length)(total_size +
395 (resource->data.pin_group.
396 pin_table_length * 2) +
397 resource->data.pin_group.
398 resource_label.
399 string_length +
400 resource->data.pin_group.
401 vendor_length);
402
403 break;
404
405 case ACPI_RESOURCE_TYPE_PIN_GROUP_FUNCTION:
406
407 total_size = (acpi_rs_length)(total_size +
408 resource->data.
409 pin_group_function.
410 resource_source.
411 string_length +
412 resource->data.
413 pin_group_function.
414 resource_source_label.
415 string_length +
416 resource->data.
417 pin_group_function.
418 vendor_length);
419
420 break;
421
422 case ACPI_RESOURCE_TYPE_PIN_GROUP_CONFIG:
423
424 total_size = (acpi_rs_length)(total_size +
425 resource->data.
426 pin_group_config.
427 resource_source.
428 string_length +
429 resource->data.
430 pin_group_config.
431 resource_source_label.
432 string_length +
433 resource->data.
434 pin_group_config.
435 vendor_length);
436
437 break;
438
439 default:
440
441 break;
442 }
443
444 /* Update the total */
445
446 aml_size_needed += total_size;
447
448 /* Point to the next object */
449
450 resource =
451 ACPI_ADD_PTR(struct acpi_resource, resource,
452 resource->length);
453 }
454
455 /* Did not find an end_tag resource descriptor */
456
457 return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
458 }
459
460 /*******************************************************************************
461 *
462 * FUNCTION: acpi_rs_get_list_length
463 *
464 * PARAMETERS: aml_buffer - Pointer to the resource byte stream
465 * aml_buffer_length - Size of aml_buffer
466 * size_needed - Where the size needed is returned
467 *
468 * RETURN: Status
469 *
470 * DESCRIPTION: Takes an external resource byte stream and calculates the size
471 * buffer needed to hold the corresponding internal resource
472 * descriptor linked list.
473 *
474 ******************************************************************************/
475
476 acpi_status
acpi_rs_get_list_length(u8 * aml_buffer,u32 aml_buffer_length,acpi_size * size_needed)477 acpi_rs_get_list_length(u8 *aml_buffer,
478 u32 aml_buffer_length, acpi_size *size_needed)
479 {
480 acpi_status status;
481 u8 *end_aml;
482 u8 *buffer;
483 u32 buffer_size;
484 u16 temp16;
485 u16 resource_length;
486 u32 extra_struct_bytes;
487 u8 resource_index;
488 u8 minimum_aml_resource_length;
489 union aml_resource *aml_resource;
490
491 ACPI_FUNCTION_TRACE(rs_get_list_length);
492
493 *size_needed = ACPI_RS_SIZE_MIN; /* Minimum size is one end_tag */
494 end_aml = aml_buffer + aml_buffer_length;
495
496 /* Walk the list of AML resource descriptors */
497
498 while (aml_buffer < end_aml) {
499
500 /* Validate the Resource Type and Resource Length */
501
502 status =
503 acpi_ut_validate_resource(NULL, aml_buffer,
504 &resource_index);
505 if (ACPI_FAILURE(status)) {
506 /*
507 * Exit on failure. Cannot continue because the descriptor length
508 * may be bogus also.
509 */
510 return_ACPI_STATUS(status);
511 }
512
513 aml_resource = (void *)aml_buffer;
514
515 /* Get the resource length and base (minimum) AML size */
516
517 resource_length = acpi_ut_get_resource_length(aml_buffer);
518 minimum_aml_resource_length =
519 acpi_gbl_resource_aml_sizes[resource_index];
520
521 /*
522 * Augment the size for descriptors with optional
523 * and/or variable length fields
524 */
525 extra_struct_bytes = 0;
526 buffer =
527 aml_buffer + acpi_ut_get_resource_header_length(aml_buffer);
528
529 switch (acpi_ut_get_resource_type(aml_buffer)) {
530 case ACPI_RESOURCE_NAME_IRQ:
531 /*
532 * IRQ Resource:
533 * Get the number of bits set in the 16-bit IRQ mask
534 */
535 ACPI_MOVE_16_TO_16(&temp16, buffer);
536 extra_struct_bytes = acpi_rs_count_set_bits(temp16);
537 break;
538
539 case ACPI_RESOURCE_NAME_DMA:
540 /*
541 * DMA Resource:
542 * Get the number of bits set in the 8-bit DMA mask
543 */
544 extra_struct_bytes = acpi_rs_count_set_bits(*buffer);
545 break;
546
547 case ACPI_RESOURCE_NAME_VENDOR_SMALL:
548 case ACPI_RESOURCE_NAME_VENDOR_LARGE:
549 /*
550 * Vendor Resource:
551 * Get the number of vendor data bytes
552 */
553 extra_struct_bytes = resource_length;
554
555 /*
556 * There is already one byte included in the minimum
557 * descriptor size. If there are extra struct bytes,
558 * subtract one from the count.
559 */
560 if (extra_struct_bytes) {
561 extra_struct_bytes--;
562 }
563 break;
564
565 case ACPI_RESOURCE_NAME_END_TAG:
566 /*
567 * End Tag: This is the normal exit
568 */
569 return_ACPI_STATUS(AE_OK);
570
571 case ACPI_RESOURCE_NAME_ADDRESS32:
572 case ACPI_RESOURCE_NAME_ADDRESS16:
573 case ACPI_RESOURCE_NAME_ADDRESS64:
574 /*
575 * Address Resource:
576 * Add the size of the optional resource_source
577 */
578 extra_struct_bytes =
579 acpi_rs_stream_option_length(resource_length,
580 minimum_aml_resource_length);
581 break;
582
583 case ACPI_RESOURCE_NAME_EXTENDED_IRQ:
584 /*
585 * Extended IRQ Resource:
586 * Using the interrupt_table_length, add 4 bytes for each additional
587 * interrupt. Note: at least one interrupt is required and is
588 * included in the minimum descriptor size (reason for the -1)
589 */
590 extra_struct_bytes = (buffer[1] - 1) * sizeof(u32);
591
592 /* Add the size of the optional resource_source */
593
594 extra_struct_bytes +=
595 acpi_rs_stream_option_length(resource_length -
596 extra_struct_bytes,
597 minimum_aml_resource_length);
598 break;
599
600 case ACPI_RESOURCE_NAME_GPIO:
601
602 /* Vendor data is optional */
603
604 if (aml_resource->gpio.vendor_length) {
605 extra_struct_bytes +=
606 aml_resource->gpio.vendor_offset -
607 aml_resource->gpio.pin_table_offset +
608 aml_resource->gpio.vendor_length;
609 } else {
610 extra_struct_bytes +=
611 aml_resource->large_header.resource_length +
612 sizeof(struct aml_resource_large_header) -
613 aml_resource->gpio.pin_table_offset;
614 }
615 break;
616
617 case ACPI_RESOURCE_NAME_PIN_FUNCTION:
618
619 /* Vendor data is optional */
620
621 if (aml_resource->pin_function.vendor_length) {
622 extra_struct_bytes +=
623 aml_resource->pin_function.vendor_offset -
624 aml_resource->pin_function.
625 pin_table_offset +
626 aml_resource->pin_function.vendor_length;
627 } else {
628 extra_struct_bytes +=
629 aml_resource->large_header.resource_length +
630 sizeof(struct aml_resource_large_header) -
631 aml_resource->pin_function.pin_table_offset;
632 }
633 break;
634
635 case ACPI_RESOURCE_NAME_SERIAL_BUS:
636
637 minimum_aml_resource_length =
638 acpi_gbl_resource_aml_serial_bus_sizes
639 [aml_resource->common_serial_bus.type];
640 extra_struct_bytes +=
641 aml_resource->common_serial_bus.resource_length -
642 minimum_aml_resource_length;
643 break;
644
645 case ACPI_RESOURCE_NAME_PIN_CONFIG:
646
647 /* Vendor data is optional */
648
649 if (aml_resource->pin_config.vendor_length) {
650 extra_struct_bytes +=
651 aml_resource->pin_config.vendor_offset -
652 aml_resource->pin_config.pin_table_offset +
653 aml_resource->pin_config.vendor_length;
654 } else {
655 extra_struct_bytes +=
656 aml_resource->large_header.resource_length +
657 sizeof(struct aml_resource_large_header) -
658 aml_resource->pin_config.pin_table_offset;
659 }
660 break;
661
662 case ACPI_RESOURCE_NAME_PIN_GROUP:
663
664 extra_struct_bytes +=
665 aml_resource->pin_group.vendor_offset -
666 aml_resource->pin_group.pin_table_offset +
667 aml_resource->pin_group.vendor_length;
668
669 break;
670
671 case ACPI_RESOURCE_NAME_PIN_GROUP_FUNCTION:
672
673 extra_struct_bytes +=
674 aml_resource->pin_group_function.vendor_offset -
675 aml_resource->pin_group_function.res_source_offset +
676 aml_resource->pin_group_function.vendor_length;
677
678 break;
679
680 case ACPI_RESOURCE_NAME_PIN_GROUP_CONFIG:
681
682 extra_struct_bytes +=
683 aml_resource->pin_group_config.vendor_offset -
684 aml_resource->pin_group_config.res_source_offset +
685 aml_resource->pin_group_config.vendor_length;
686
687 break;
688
689 default:
690
691 break;
692 }
693
694 /*
695 * Update the required buffer size for the internal descriptor structs
696 *
697 * Important: Round the size up for the appropriate alignment. This
698 * is a requirement on IA64.
699 */
700 if (acpi_ut_get_resource_type(aml_buffer) ==
701 ACPI_RESOURCE_NAME_SERIAL_BUS) {
702 buffer_size =
703 acpi_gbl_resource_struct_serial_bus_sizes
704 [aml_resource->common_serial_bus.type] +
705 extra_struct_bytes;
706 } else {
707 buffer_size =
708 acpi_gbl_resource_struct_sizes[resource_index] +
709 extra_struct_bytes;
710 }
711
712 buffer_size = (u32)ACPI_ROUND_UP_TO_NATIVE_WORD(buffer_size);
713 *size_needed += buffer_size;
714
715 ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES,
716 "Type %.2X, AmlLength %.2X InternalLength %.2X\n",
717 acpi_ut_get_resource_type(aml_buffer),
718 acpi_ut_get_descriptor_length(aml_buffer),
719 buffer_size));
720
721 /*
722 * Point to the next resource within the AML stream using the length
723 * contained in the resource descriptor header
724 */
725 aml_buffer += acpi_ut_get_descriptor_length(aml_buffer);
726 }
727
728 /* Did not find an end_tag resource descriptor */
729
730 return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
731 }
732
733 /*******************************************************************************
734 *
735 * FUNCTION: acpi_rs_get_pci_routing_table_length
736 *
737 * PARAMETERS: package_object - Pointer to the package object
738 * buffer_size_needed - u32 pointer of the size buffer
739 * needed to properly return the
740 * parsed data
741 *
742 * RETURN: Status
743 *
744 * DESCRIPTION: Given a package representing a PCI routing table, this
745 * calculates the size of the corresponding linked list of
746 * descriptions.
747 *
748 ******************************************************************************/
749
750 acpi_status
acpi_rs_get_pci_routing_table_length(union acpi_operand_object * package_object,acpi_size * buffer_size_needed)751 acpi_rs_get_pci_routing_table_length(union acpi_operand_object *package_object,
752 acpi_size *buffer_size_needed)
753 {
754 u32 number_of_elements;
755 acpi_size temp_size_needed = 0;
756 union acpi_operand_object **top_object_list;
757 u32 index;
758 union acpi_operand_object *package_element;
759 union acpi_operand_object **sub_object_list;
760 u8 name_found;
761 u32 table_index;
762
763 ACPI_FUNCTION_TRACE(rs_get_pci_routing_table_length);
764
765 number_of_elements = package_object->package.count;
766
767 /*
768 * Calculate the size of the return buffer.
769 * The base size is the number of elements * the sizes of the
770 * structures. Additional space for the strings is added below.
771 * The minus one is to subtract the size of the u8 Source[1]
772 * member because it is added below.
773 *
774 * But each PRT_ENTRY structure has a pointer to a string and
775 * the size of that string must be found.
776 */
777 top_object_list = package_object->package.elements;
778
779 for (index = 0; index < number_of_elements; index++) {
780
781 /* Dereference the subpackage */
782
783 package_element = *top_object_list;
784
785 /* We must have a valid Package object */
786
787 if (!package_element ||
788 (package_element->common.type != ACPI_TYPE_PACKAGE)) {
789 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
790 }
791
792 /*
793 * The sub_object_list will now point to an array of the
794 * four IRQ elements: Address, Pin, Source and source_index
795 */
796 sub_object_list = package_element->package.elements;
797
798 /* Scan the irq_table_elements for the Source Name String */
799
800 name_found = FALSE;
801
802 for (table_index = 0;
803 table_index < package_element->package.count
804 && !name_found; table_index++) {
805 if (*sub_object_list && /* Null object allowed */
806 ((ACPI_TYPE_STRING ==
807 (*sub_object_list)->common.type) ||
808 ((ACPI_TYPE_LOCAL_REFERENCE ==
809 (*sub_object_list)->common.type) &&
810 ((*sub_object_list)->reference.class ==
811 ACPI_REFCLASS_NAME)))) {
812 name_found = TRUE;
813 } else {
814 /* Look at the next element */
815
816 sub_object_list++;
817 }
818 }
819
820 temp_size_needed += (sizeof(struct acpi_pci_routing_table) - 4);
821
822 /* Was a String type found? */
823
824 if (name_found) {
825 if ((*sub_object_list)->common.type == ACPI_TYPE_STRING) {
826 /*
827 * The length String.Length field does not include the
828 * terminating NULL, add 1
829 */
830 temp_size_needed += ((acpi_size)
831 (*sub_object_list)->string.
832 length + 1);
833 } else {
834 temp_size_needed += acpi_ns_get_pathname_length((*sub_object_list)->reference.node);
835 }
836 } else {
837 /*
838 * If no name was found, then this is a NULL, which is
839 * translated as a u32 zero.
840 */
841 temp_size_needed += sizeof(u32);
842 }
843
844 /* Round up the size since each element must be aligned */
845
846 temp_size_needed = ACPI_ROUND_UP_TO_64BIT(temp_size_needed);
847
848 /* Point to the next union acpi_operand_object */
849
850 top_object_list++;
851 }
852
853 /*
854 * Add an extra element to the end of the list, essentially a
855 * NULL terminator
856 */
857 *buffer_size_needed =
858 temp_size_needed + sizeof(struct acpi_pci_routing_table);
859 return_ACPI_STATUS(AE_OK);
860 }
861