Merge branch 'WIP.locking/atomics' into locking/core
[sfrench/cifs-2.6.git] / drivers / acpi / acpica / rscalc.c
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_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
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
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 }