]> git.karo-electronics.de Git - karo-tx-linux.git/blob - drivers/acpi/acpica/utresrc.c
xfs: fix spurious spin_is_locked() assert failures on non-smp kernels
[karo-tx-linux.git] / drivers / acpi / acpica / utresrc.c
1 /*******************************************************************************
2  *
3  * Module Name: utresrc - Resource management utilities
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
48 #define _COMPONENT          ACPI_UTILITIES
49 ACPI_MODULE_NAME("utresrc")
50
51 #if defined(ACPI_DEBUG_OUTPUT) || defined (ACPI_DISASSEMBLER) || defined (ACPI_DEBUGGER)
52 /*
53  * Strings used to decode resource descriptors.
54  * Used by both the disassembler and the debugger resource dump routines
55  */
56 const char *acpi_gbl_bm_decode[] = {
57         "NotBusMaster",
58         "BusMaster"
59 };
60
61 const char *acpi_gbl_config_decode[] = {
62         "0 - Good Configuration",
63         "1 - Acceptable Configuration",
64         "2 - Suboptimal Configuration",
65         "3 - ***Invalid Configuration***",
66 };
67
68 const char *acpi_gbl_consume_decode[] = {
69         "ResourceProducer",
70         "ResourceConsumer"
71 };
72
73 const char *acpi_gbl_dec_decode[] = {
74         "PosDecode",
75         "SubDecode"
76 };
77
78 const char *acpi_gbl_he_decode[] = {
79         "Level",
80         "Edge"
81 };
82
83 const char *acpi_gbl_io_decode[] = {
84         "Decode10",
85         "Decode16"
86 };
87
88 const char *acpi_gbl_ll_decode[] = {
89         "ActiveHigh",
90         "ActiveLow",
91         "ActiveBoth",
92         "Reserved"
93 };
94
95 const char *acpi_gbl_max_decode[] = {
96         "MaxNotFixed",
97         "MaxFixed"
98 };
99
100 const char *acpi_gbl_mem_decode[] = {
101         "NonCacheable",
102         "Cacheable",
103         "WriteCombining",
104         "Prefetchable"
105 };
106
107 const char *acpi_gbl_min_decode[] = {
108         "MinNotFixed",
109         "MinFixed"
110 };
111
112 const char *acpi_gbl_mtp_decode[] = {
113         "AddressRangeMemory",
114         "AddressRangeReserved",
115         "AddressRangeACPI",
116         "AddressRangeNVS"
117 };
118
119 const char *acpi_gbl_rng_decode[] = {
120         "InvalidRanges",
121         "NonISAOnlyRanges",
122         "ISAOnlyRanges",
123         "EntireRange"
124 };
125
126 const char *acpi_gbl_rw_decode[] = {
127         "ReadOnly",
128         "ReadWrite"
129 };
130
131 const char *acpi_gbl_shr_decode[] = {
132         "Exclusive",
133         "Shared",
134         "ExclusiveAndWake",     /* ACPI 5.0 */
135         "SharedAndWake"         /* ACPI 5.0 */
136 };
137
138 const char *acpi_gbl_siz_decode[] = {
139         "Transfer8",
140         "Transfer8_16",
141         "Transfer16",
142         "InvalidSize"
143 };
144
145 const char *acpi_gbl_trs_decode[] = {
146         "DenseTranslation",
147         "SparseTranslation"
148 };
149
150 const char *acpi_gbl_ttp_decode[] = {
151         "TypeStatic",
152         "TypeTranslation"
153 };
154
155 const char *acpi_gbl_typ_decode[] = {
156         "Compatibility",
157         "TypeA",
158         "TypeB",
159         "TypeF"
160 };
161
162 const char *acpi_gbl_ppc_decode[] = {
163         "PullDefault",
164         "PullUp",
165         "PullDown",
166         "PullNone"
167 };
168
169 const char *acpi_gbl_ior_decode[] = {
170         "IoRestrictionNone",
171         "IoRestrictionInputOnly",
172         "IoRestrictionOutputOnly",
173         "IoRestrictionNoneAndPreserve"
174 };
175
176 const char *acpi_gbl_dts_decode[] = {
177         "Width8bit",
178         "Width16bit",
179         "Width32bit",
180         "Width64bit",
181         "Width128bit",
182         "Width256bit",
183 };
184
185 /* GPIO connection type */
186
187 const char *acpi_gbl_ct_decode[] = {
188         "Interrupt",
189         "I/O"
190 };
191
192 /* Serial bus type */
193
194 const char *acpi_gbl_sbt_decode[] = {
195         "/* UNKNOWN serial bus type */",
196         "I2C",
197         "SPI",
198         "UART"
199 };
200
201 /* I2C serial bus access mode */
202
203 const char *acpi_gbl_am_decode[] = {
204         "AddressingMode7Bit",
205         "AddressingMode10Bit"
206 };
207
208 /* I2C serial bus slave mode */
209
210 const char *acpi_gbl_sm_decode[] = {
211         "ControllerInitiated",
212         "DeviceInitiated"
213 };
214
215 /* SPI serial bus wire mode */
216
217 const char *acpi_gbl_wm_decode[] = {
218         "FourWireMode",
219         "ThreeWireMode"
220 };
221
222 /* SPI serial clock phase */
223
224 const char *acpi_gbl_cph_decode[] = {
225         "ClockPhaseFirst",
226         "ClockPhaseSecond"
227 };
228
229 /* SPI serial bus clock polarity */
230
231 const char *acpi_gbl_cpo_decode[] = {
232         "ClockPolarityLow",
233         "ClockPolarityHigh"
234 };
235
236 /* SPI serial bus device polarity */
237
238 const char *acpi_gbl_dp_decode[] = {
239         "PolarityLow",
240         "PolarityHigh"
241 };
242
243 /* UART serial bus endian */
244
245 const char *acpi_gbl_ed_decode[] = {
246         "LittleEndian",
247         "BigEndian"
248 };
249
250 /* UART serial bus bits per byte */
251
252 const char *acpi_gbl_bpb_decode[] = {
253         "DataBitsFive",
254         "DataBitsSix",
255         "DataBitsSeven",
256         "DataBitsEight",
257         "DataBitsNine",
258         "/* UNKNOWN Bits per byte */",
259         "/* UNKNOWN Bits per byte */",
260         "/* UNKNOWN Bits per byte */"
261 };
262
263 /* UART serial bus stop bits */
264
265 const char *acpi_gbl_sb_decode[] = {
266         "StopBitsZero",
267         "StopBitsOne",
268         "StopBitsOnePlusHalf",
269         "StopBitsTwo"
270 };
271
272 /* UART serial bus flow control */
273
274 const char *acpi_gbl_fc_decode[] = {
275         "FlowControlNone",
276         "FlowControlHardware",
277         "FlowControlXON",
278         "/* UNKNOWN flow control keyword */"
279 };
280
281 /* UART serial bus parity type */
282
283 const char *acpi_gbl_pt_decode[] = {
284         "ParityTypeNone",
285         "ParityTypeEven",
286         "ParityTypeOdd",
287         "ParityTypeMark",
288         "ParityTypeSpace",
289         "/* UNKNOWN parity keyword */",
290         "/* UNKNOWN parity keyword */",
291         "/* UNKNOWN parity keyword */"
292 };
293
294 #endif
295
296 /*
297  * Base sizes of the raw AML resource descriptors, indexed by resource type.
298  * Zero indicates a reserved (and therefore invalid) resource type.
299  */
300 const u8 acpi_gbl_resource_aml_sizes[] = {
301         /* Small descriptors */
302
303         0,
304         0,
305         0,
306         0,
307         ACPI_AML_SIZE_SMALL(struct aml_resource_irq),
308         ACPI_AML_SIZE_SMALL(struct aml_resource_dma),
309         ACPI_AML_SIZE_SMALL(struct aml_resource_start_dependent),
310         ACPI_AML_SIZE_SMALL(struct aml_resource_end_dependent),
311         ACPI_AML_SIZE_SMALL(struct aml_resource_io),
312         ACPI_AML_SIZE_SMALL(struct aml_resource_fixed_io),
313         ACPI_AML_SIZE_SMALL(struct aml_resource_fixed_dma),
314         0,
315         0,
316         0,
317         ACPI_AML_SIZE_SMALL(struct aml_resource_vendor_small),
318         ACPI_AML_SIZE_SMALL(struct aml_resource_end_tag),
319
320         /* Large descriptors */
321
322         0,
323         ACPI_AML_SIZE_LARGE(struct aml_resource_memory24),
324         ACPI_AML_SIZE_LARGE(struct aml_resource_generic_register),
325         0,
326         ACPI_AML_SIZE_LARGE(struct aml_resource_vendor_large),
327         ACPI_AML_SIZE_LARGE(struct aml_resource_memory32),
328         ACPI_AML_SIZE_LARGE(struct aml_resource_fixed_memory32),
329         ACPI_AML_SIZE_LARGE(struct aml_resource_address32),
330         ACPI_AML_SIZE_LARGE(struct aml_resource_address16),
331         ACPI_AML_SIZE_LARGE(struct aml_resource_extended_irq),
332         ACPI_AML_SIZE_LARGE(struct aml_resource_address64),
333         ACPI_AML_SIZE_LARGE(struct aml_resource_extended_address64),
334         ACPI_AML_SIZE_LARGE(struct aml_resource_gpio),
335         0,
336         ACPI_AML_SIZE_LARGE(struct aml_resource_common_serialbus),
337 };
338
339 const u8 acpi_gbl_resource_aml_serial_bus_sizes[] = {
340         0,
341         ACPI_AML_SIZE_LARGE(struct aml_resource_i2c_serialbus),
342         ACPI_AML_SIZE_LARGE(struct aml_resource_spi_serialbus),
343         ACPI_AML_SIZE_LARGE(struct aml_resource_uart_serialbus),
344 };
345
346 /*
347  * Resource types, used to validate the resource length field.
348  * The length of fixed-length types must match exactly, variable
349  * lengths must meet the minimum required length, etc.
350  * Zero indicates a reserved (and therefore invalid) resource type.
351  */
352 static const u8 acpi_gbl_resource_types[] = {
353         /* Small descriptors */
354
355         0,
356         0,
357         0,
358         0,
359         ACPI_SMALL_VARIABLE_LENGTH,     /* 04 IRQ */
360         ACPI_FIXED_LENGTH,      /* 05 DMA */
361         ACPI_SMALL_VARIABLE_LENGTH,     /* 06 start_dependent_functions */
362         ACPI_FIXED_LENGTH,      /* 07 end_dependent_functions */
363         ACPI_FIXED_LENGTH,      /* 08 IO */
364         ACPI_FIXED_LENGTH,      /* 09 fixed_IO */
365         ACPI_FIXED_LENGTH,      /* 0A fixed_DMA */
366         0,
367         0,
368         0,
369         ACPI_VARIABLE_LENGTH,   /* 0E vendor_short */
370         ACPI_FIXED_LENGTH,      /* 0F end_tag */
371
372         /* Large descriptors */
373
374         0,
375         ACPI_FIXED_LENGTH,      /* 01 Memory24 */
376         ACPI_FIXED_LENGTH,      /* 02 generic_register */
377         0,
378         ACPI_VARIABLE_LENGTH,   /* 04 vendor_long */
379         ACPI_FIXED_LENGTH,      /* 05 Memory32 */
380         ACPI_FIXED_LENGTH,      /* 06 memory32_fixed */
381         ACPI_VARIABLE_LENGTH,   /* 07 Dword* address */
382         ACPI_VARIABLE_LENGTH,   /* 08 Word* address */
383         ACPI_VARIABLE_LENGTH,   /* 09 extended_IRQ */
384         ACPI_VARIABLE_LENGTH,   /* 0A Qword* address */
385         ACPI_FIXED_LENGTH,      /* 0B Extended* address */
386         ACPI_VARIABLE_LENGTH,   /* 0C Gpio* */
387         0,
388         ACPI_VARIABLE_LENGTH    /* 0E *serial_bus */
389 };
390
391 /*******************************************************************************
392  *
393  * FUNCTION:    acpi_ut_walk_aml_resources
394  *
395  * PARAMETERS:  walk_state          - Current walk info
396  * PARAMETERS:  aml                 - Pointer to the raw AML resource template
397  *              aml_length          - Length of the entire template
398  *              user_function       - Called once for each descriptor found. If
399  *                                    NULL, a pointer to the end_tag is returned
400  *              context             - Passed to user_function
401  *
402  * RETURN:      Status
403  *
404  * DESCRIPTION: Walk a raw AML resource list(buffer). User function called
405  *              once for each resource found.
406  *
407  ******************************************************************************/
408
409 acpi_status
410 acpi_ut_walk_aml_resources(struct acpi_walk_state *walk_state,
411                            u8 *aml,
412                            acpi_size aml_length,
413                            acpi_walk_aml_callback user_function, void **context)
414 {
415         acpi_status status;
416         u8 *end_aml;
417         u8 resource_index;
418         u32 length;
419         u32 offset = 0;
420         u8 end_tag[2] = { 0x79, 0x00 };
421
422         ACPI_FUNCTION_TRACE(ut_walk_aml_resources);
423
424         /* The absolute minimum resource template is one end_tag descriptor */
425
426         if (aml_length < sizeof(struct aml_resource_end_tag)) {
427                 return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
428         }
429
430         /* Point to the end of the resource template buffer */
431
432         end_aml = aml + aml_length;
433
434         /* Walk the byte list, abort on any invalid descriptor type or length */
435
436         while (aml < end_aml) {
437
438                 /* Validate the Resource Type and Resource Length */
439
440                 status =
441                     acpi_ut_validate_resource(walk_state, aml, &resource_index);
442                 if (ACPI_FAILURE(status)) {
443                         /*
444                          * Exit on failure. Cannot continue because the descriptor
445                          * length may be bogus also.
446                          */
447                         return_ACPI_STATUS(status);
448                 }
449
450                 /* Get the length of this descriptor */
451
452                 length = acpi_ut_get_descriptor_length(aml);
453
454                 /* Invoke the user function */
455
456                 if (user_function) {
457                         status =
458                             user_function(aml, length, offset, resource_index,
459                                           context);
460                         if (ACPI_FAILURE(status)) {
461                                 return_ACPI_STATUS(status);
462                         }
463                 }
464
465                 /* An end_tag descriptor terminates this resource template */
466
467                 if (acpi_ut_get_resource_type(aml) ==
468                     ACPI_RESOURCE_NAME_END_TAG) {
469                         /*
470                          * There must be at least one more byte in the buffer for
471                          * the 2nd byte of the end_tag
472                          */
473                         if ((aml + 1) >= end_aml) {
474                                 return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
475                         }
476
477                         /*
478                          * The end_tag opcode must be followed by a zero byte.
479                          * Although this byte is technically defined to be a checksum,
480                          * in practice, all ASL compilers set this byte to zero.
481                          */
482                         if (*(aml + 1) != 0) {
483                                 return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
484                         }
485
486                         /* Return the pointer to the end_tag if requested */
487
488                         if (!user_function) {
489                                 *context = aml;
490                         }
491
492                         /* Normal exit */
493
494                         return_ACPI_STATUS(AE_OK);
495                 }
496
497                 aml += length;
498                 offset += length;
499         }
500
501         /* Did not find an end_tag descriptor */
502
503         if (user_function) {
504
505                 /* Insert an end_tag anyway. acpi_rs_get_list_length always leaves room */
506
507                 (void)acpi_ut_validate_resource(walk_state, end_tag,
508                                                 &resource_index);
509                 status =
510                     user_function(end_tag, 2, offset, resource_index, context);
511                 if (ACPI_FAILURE(status)) {
512                         return_ACPI_STATUS(status);
513                 }
514         }
515
516         return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
517 }
518
519 /*******************************************************************************
520  *
521  * FUNCTION:    acpi_ut_validate_resource
522  *
523  * PARAMETERS:  walk_state          - Current walk info
524  *              aml                 - Pointer to the raw AML resource descriptor
525  *              return_index        - Where the resource index is returned. NULL
526  *                                    if the index is not required.
527  *
528  * RETURN:      Status, and optionally the Index into the global resource tables
529  *
530  * DESCRIPTION: Validate an AML resource descriptor by checking the Resource
531  *              Type and Resource Length. Returns an index into the global
532  *              resource information/dispatch tables for later use.
533  *
534  ******************************************************************************/
535
536 acpi_status
537 acpi_ut_validate_resource(struct acpi_walk_state *walk_state,
538                           void *aml, u8 *return_index)
539 {
540         union aml_resource *aml_resource;
541         u8 resource_type;
542         u8 resource_index;
543         acpi_rs_length resource_length;
544         acpi_rs_length minimum_resource_length;
545
546         ACPI_FUNCTION_ENTRY();
547
548         /*
549          * 1) Validate the resource_type field (Byte 0)
550          */
551         resource_type = ACPI_GET8(aml);
552
553         /*
554          * Byte 0 contains the descriptor name (Resource Type)
555          * Examine the large/small bit in the resource header
556          */
557         if (resource_type & ACPI_RESOURCE_NAME_LARGE) {
558
559                 /* Verify the large resource type (name) against the max */
560
561                 if (resource_type > ACPI_RESOURCE_NAME_LARGE_MAX) {
562                         goto invalid_resource;
563                 }
564
565                 /*
566                  * Large Resource Type -- bits 6:0 contain the name
567                  * Translate range 0x80-0x8B to index range 0x10-0x1B
568                  */
569                 resource_index = (u8) (resource_type - 0x70);
570         } else {
571                 /*
572                  * Small Resource Type -- bits 6:3 contain the name
573                  * Shift range to index range 0x00-0x0F
574                  */
575                 resource_index = (u8)
576                     ((resource_type & ACPI_RESOURCE_NAME_SMALL_MASK) >> 3);
577         }
578
579         /*
580          * Check validity of the resource type, via acpi_gbl_resource_types.
581          * Zero indicates an invalid resource.
582          */
583         if (!acpi_gbl_resource_types[resource_index]) {
584                 goto invalid_resource;
585         }
586
587         /*
588          * Validate the resource_length field. This ensures that the length
589          * is at least reasonable, and guarantees that it is non-zero.
590          */
591         resource_length = acpi_ut_get_resource_length(aml);
592         minimum_resource_length = acpi_gbl_resource_aml_sizes[resource_index];
593
594         /* Validate based upon the type of resource - fixed length or variable */
595
596         switch (acpi_gbl_resource_types[resource_index]) {
597         case ACPI_FIXED_LENGTH:
598
599                 /* Fixed length resource, length must match exactly */
600
601                 if (resource_length != minimum_resource_length) {
602                         goto bad_resource_length;
603                 }
604                 break;
605
606         case ACPI_VARIABLE_LENGTH:
607
608                 /* Variable length resource, length must be at least the minimum */
609
610                 if (resource_length < minimum_resource_length) {
611                         goto bad_resource_length;
612                 }
613                 break;
614
615         case ACPI_SMALL_VARIABLE_LENGTH:
616
617                 /* Small variable length resource, length can be (Min) or (Min-1) */
618
619                 if ((resource_length > minimum_resource_length) ||
620                     (resource_length < (minimum_resource_length - 1))) {
621                         goto bad_resource_length;
622                 }
623                 break;
624
625         default:
626
627                 /* Shouldn't happen (because of validation earlier), but be sure */
628
629                 goto invalid_resource;
630         }
631
632         aml_resource = ACPI_CAST_PTR(union aml_resource, aml);
633         if (resource_type == ACPI_RESOURCE_NAME_SERIAL_BUS) {
634
635                 /* Validate the bus_type field */
636
637                 if ((aml_resource->common_serial_bus.type == 0) ||
638                     (aml_resource->common_serial_bus.type >
639                      AML_RESOURCE_MAX_SERIALBUSTYPE)) {
640                         if (walk_state) {
641                                 ACPI_ERROR((AE_INFO,
642                                             "Invalid/unsupported SerialBus resource descriptor: BusType 0x%2.2X",
643                                             aml_resource->common_serial_bus.
644                                             type));
645                         }
646                         return (AE_AML_INVALID_RESOURCE_TYPE);
647                 }
648         }
649
650         /* Optionally return the resource table index */
651
652         if (return_index) {
653                 *return_index = resource_index;
654         }
655
656         return (AE_OK);
657
658 invalid_resource:
659
660         if (walk_state) {
661                 ACPI_ERROR((AE_INFO,
662                             "Invalid/unsupported resource descriptor: Type 0x%2.2X",
663                             resource_type));
664         }
665         return (AE_AML_INVALID_RESOURCE_TYPE);
666
667 bad_resource_length:
668
669         if (walk_state) {
670                 ACPI_ERROR((AE_INFO,
671                             "Invalid resource descriptor length: Type "
672                             "0x%2.2X, Length 0x%4.4X, MinLength 0x%4.4X",
673                             resource_type, resource_length,
674                             minimum_resource_length));
675         }
676         return (AE_AML_BAD_RESOURCE_LENGTH);
677 }
678
679 /*******************************************************************************
680  *
681  * FUNCTION:    acpi_ut_get_resource_type
682  *
683  * PARAMETERS:  aml             - Pointer to the raw AML resource descriptor
684  *
685  * RETURN:      The Resource Type with no extraneous bits (except the
686  *              Large/Small descriptor bit -- this is left alone)
687  *
688  * DESCRIPTION: Extract the Resource Type/Name from the first byte of
689  *              a resource descriptor.
690  *
691  ******************************************************************************/
692
693 u8 acpi_ut_get_resource_type(void *aml)
694 {
695         ACPI_FUNCTION_ENTRY();
696
697         /*
698          * Byte 0 contains the descriptor name (Resource Type)
699          * Examine the large/small bit in the resource header
700          */
701         if (ACPI_GET8(aml) & ACPI_RESOURCE_NAME_LARGE) {
702
703                 /* Large Resource Type -- bits 6:0 contain the name */
704
705                 return (ACPI_GET8(aml));
706         } else {
707                 /* Small Resource Type -- bits 6:3 contain the name */
708
709                 return ((u8) (ACPI_GET8(aml) & ACPI_RESOURCE_NAME_SMALL_MASK));
710         }
711 }
712
713 /*******************************************************************************
714  *
715  * FUNCTION:    acpi_ut_get_resource_length
716  *
717  * PARAMETERS:  aml             - Pointer to the raw AML resource descriptor
718  *
719  * RETURN:      Byte Length
720  *
721  * DESCRIPTION: Get the "Resource Length" of a raw AML descriptor. By
722  *              definition, this does not include the size of the descriptor
723  *              header or the length field itself.
724  *
725  ******************************************************************************/
726
727 u16 acpi_ut_get_resource_length(void *aml)
728 {
729         acpi_rs_length resource_length;
730
731         ACPI_FUNCTION_ENTRY();
732
733         /*
734          * Byte 0 contains the descriptor name (Resource Type)
735          * Examine the large/small bit in the resource header
736          */
737         if (ACPI_GET8(aml) & ACPI_RESOURCE_NAME_LARGE) {
738
739                 /* Large Resource type -- bytes 1-2 contain the 16-bit length */
740
741                 ACPI_MOVE_16_TO_16(&resource_length, ACPI_ADD_PTR(u8, aml, 1));
742
743         } else {
744                 /* Small Resource type -- bits 2:0 of byte 0 contain the length */
745
746                 resource_length = (u16) (ACPI_GET8(aml) &
747                                          ACPI_RESOURCE_NAME_SMALL_LENGTH_MASK);
748         }
749
750         return (resource_length);
751 }
752
753 /*******************************************************************************
754  *
755  * FUNCTION:    acpi_ut_get_resource_header_length
756  *
757  * PARAMETERS:  aml             - Pointer to the raw AML resource descriptor
758  *
759  * RETURN:      Length of the AML header (depends on large/small descriptor)
760  *
761  * DESCRIPTION: Get the length of the header for this resource.
762  *
763  ******************************************************************************/
764
765 u8 acpi_ut_get_resource_header_length(void *aml)
766 {
767         ACPI_FUNCTION_ENTRY();
768
769         /* Examine the large/small bit in the resource header */
770
771         if (ACPI_GET8(aml) & ACPI_RESOURCE_NAME_LARGE) {
772                 return (sizeof(struct aml_resource_large_header));
773         } else {
774                 return (sizeof(struct aml_resource_small_header));
775         }
776 }
777
778 /*******************************************************************************
779  *
780  * FUNCTION:    acpi_ut_get_descriptor_length
781  *
782  * PARAMETERS:  aml             - Pointer to the raw AML resource descriptor
783  *
784  * RETURN:      Byte length
785  *
786  * DESCRIPTION: Get the total byte length of a raw AML descriptor, including the
787  *              length of the descriptor header and the length field itself.
788  *              Used to walk descriptor lists.
789  *
790  ******************************************************************************/
791
792 u32 acpi_ut_get_descriptor_length(void *aml)
793 {
794         ACPI_FUNCTION_ENTRY();
795
796         /*
797          * Get the Resource Length (does not include header length) and add
798          * the header length (depends on if this is a small or large resource)
799          */
800         return (acpi_ut_get_resource_length(aml) +
801                 acpi_ut_get_resource_header_length(aml));
802 }
803
804 /*******************************************************************************
805  *
806  * FUNCTION:    acpi_ut_get_resource_end_tag
807  *
808  * PARAMETERS:  obj_desc        - The resource template buffer object
809  *              end_tag         - Where the pointer to the end_tag is returned
810  *
811  * RETURN:      Status, pointer to the end tag
812  *
813  * DESCRIPTION: Find the end_tag resource descriptor in an AML resource template
814  *              Note: allows a buffer length of zero.
815  *
816  ******************************************************************************/
817
818 acpi_status
819 acpi_ut_get_resource_end_tag(union acpi_operand_object *obj_desc, u8 **end_tag)
820 {
821         acpi_status status;
822
823         ACPI_FUNCTION_TRACE(ut_get_resource_end_tag);
824
825         /* Allow a buffer length of zero */
826
827         if (!obj_desc->buffer.length) {
828                 *end_tag = obj_desc->buffer.pointer;
829                 return_ACPI_STATUS(AE_OK);
830         }
831
832         /* Validate the template and get a pointer to the end_tag */
833
834         status = acpi_ut_walk_aml_resources(NULL, obj_desc->buffer.pointer,
835                                             obj_desc->buffer.length, NULL,
836                                             (void **)end_tag);
837
838         return_ACPI_STATUS(status);
839 }