xref: /freebsd/sys/contrib/dev/acpica/components/utilities/utresrc.c (revision 13464e4a44fc58490a03bb8bfc7e3c972e9c30b2)
1 /*******************************************************************************
2  *
3  * Module Name: utresrc - Resource management utilities
4  *
5  ******************************************************************************/
6 
7 /******************************************************************************
8  *
9  * 1. Copyright Notice
10  *
11  * Some or all of this work - Copyright (c) 1999 - 2017, Intel Corp.
12  * All rights reserved.
13  *
14  * 2. License
15  *
16  * 2.1. This is your license from Intel Corp. under its intellectual property
17  * rights. You may have additional license terms from the party that provided
18  * you this software, covering your right to use that party's intellectual
19  * property rights.
20  *
21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
22  * copy of the source code appearing in this file ("Covered Code") an
23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
24  * base code distributed originally by Intel ("Original Intel Code") to copy,
25  * make derivatives, distribute, use and display any portion of the Covered
26  * Code in any form, with the right to sublicense such rights; and
27  *
28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
29  * license (with the right to sublicense), under only those claims of Intel
30  * patents that are infringed by the Original Intel Code, to make, use, sell,
31  * offer to sell, and import the Covered Code and derivative works thereof
32  * solely to the minimum extent necessary to exercise the above copyright
33  * license, and in no event shall the patent license extend to any additions
34  * to or modifications of the Original Intel Code. No other license or right
35  * is granted directly or by implication, estoppel or otherwise;
36  *
37  * The above copyright and patent license is granted only if the following
38  * conditions are met:
39  *
40  * 3. Conditions
41  *
42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
43  * Redistribution of source code of any substantial portion of the Covered
44  * Code or modification with rights to further distribute source must include
45  * the above Copyright Notice, the above License, this list of Conditions,
46  * and the following Disclaimer and Export Compliance provision. In addition,
47  * Licensee must cause all Covered Code to which Licensee contributes to
48  * contain a file documenting the changes Licensee made to create that Covered
49  * Code and the date of any change. Licensee must include in that file the
50  * documentation of any changes made by any predecessor Licensee. Licensee
51  * must include a prominent statement that the modification is derived,
52  * directly or indirectly, from Original Intel Code.
53  *
54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
55  * Redistribution of source code of any substantial portion of the Covered
56  * Code or modification without rights to further distribute source must
57  * include the following Disclaimer and Export Compliance provision in the
58  * documentation and/or other materials provided with distribution. In
59  * addition, Licensee may not authorize further sublicense of source of any
60  * portion of the Covered Code, and must include terms to the effect that the
61  * license from Licensee to its licensee is limited to the intellectual
62  * property embodied in the software Licensee provides to its licensee, and
63  * not to intellectual property embodied in modifications its licensee may
64  * make.
65  *
66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
67  * substantial portion of the Covered Code or modification must reproduce the
68  * above Copyright Notice, and the following Disclaimer and Export Compliance
69  * provision in the documentation and/or other materials provided with the
70  * distribution.
71  *
72  * 3.4. Intel retains all right, title, and interest in and to the Original
73  * Intel Code.
74  *
75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
76  * Intel shall be used in advertising or otherwise to promote the sale, use or
77  * other dealings in products derived from or relating to the Covered Code
78  * without prior written authorization from Intel.
79  *
80  * 4. Disclaimer and Export Compliance
81  *
82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
83  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
85  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
86  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
88  * PARTICULAR PURPOSE.
89  *
90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
97  * LIMITED REMEDY.
98  *
99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
100  * software or system incorporating such software without first obtaining any
101  * required license or other approval from the U. S. Department of Commerce or
102  * any other agency or department of the United States Government. In the
103  * event Licensee exports any such software from the United States or
104  * re-exports any such software from a foreign destination, Licensee shall
105  * ensure that the distribution and export/re-export of the software is in
106  * compliance with all laws, regulations, orders, or other restrictions of the
107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
108  * any of its subsidiaries will export/re-export any technical data, process,
109  * software, or service, directly or indirectly, to any country for which the
110  * United States government or any agency thereof requires an export license,
111  * other governmental approval, or letter of assurance, without first obtaining
112  * such license, approval or letter.
113  *
114  *****************************************************************************
115  *
116  * Alternatively, you may choose to be licensed under the terms of the
117  * following license:
118  *
119  * Redistribution and use in source and binary forms, with or without
120  * modification, are permitted provided that the following conditions
121  * are met:
122  * 1. Redistributions of source code must retain the above copyright
123  *    notice, this list of conditions, and the following disclaimer,
124  *    without modification.
125  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
126  *    substantially similar to the "NO WARRANTY" disclaimer below
127  *    ("Disclaimer") and any redistribution must be conditioned upon
128  *    including a substantially similar Disclaimer requirement for further
129  *    binary redistribution.
130  * 3. Neither the names of the above-listed copyright holders nor the names
131  *    of any contributors may be used to endorse or promote products derived
132  *    from this software without specific prior written permission.
133  *
134  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
135  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
136  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
137  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
138  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
139  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
140  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
141  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
142  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
143  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
144  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
145  *
146  * Alternatively, you may choose to be licensed under the terms of the
147  * GNU General Public License ("GPL") version 2 as published by the Free
148  * Software Foundation.
149  *
150  *****************************************************************************/
151 
152 #include <contrib/dev/acpica/include/acpi.h>
153 #include <contrib/dev/acpica/include/accommon.h>
154 #include <contrib/dev/acpica/include/acresrc.h>
155 
156 
157 #define _COMPONENT          ACPI_UTILITIES
158         ACPI_MODULE_NAME    ("utresrc")
159 
160 
161 /*
162  * Base sizes of the raw AML resource descriptors, indexed by resource type.
163  * Zero indicates a reserved (and therefore invalid) resource type.
164  */
165 const UINT8                 AcpiGbl_ResourceAmlSizes[] =
166 {
167     /* Small descriptors */
168 
169     0,
170     0,
171     0,
172     0,
173     ACPI_AML_SIZE_SMALL (AML_RESOURCE_IRQ),
174     ACPI_AML_SIZE_SMALL (AML_RESOURCE_DMA),
175     ACPI_AML_SIZE_SMALL (AML_RESOURCE_START_DEPENDENT),
176     ACPI_AML_SIZE_SMALL (AML_RESOURCE_END_DEPENDENT),
177     ACPI_AML_SIZE_SMALL (AML_RESOURCE_IO),
178     ACPI_AML_SIZE_SMALL (AML_RESOURCE_FIXED_IO),
179     ACPI_AML_SIZE_SMALL (AML_RESOURCE_FIXED_DMA),
180     0,
181     0,
182     0,
183     ACPI_AML_SIZE_SMALL (AML_RESOURCE_VENDOR_SMALL),
184     ACPI_AML_SIZE_SMALL (AML_RESOURCE_END_TAG),
185 
186     /* Large descriptors */
187 
188     0,
189     ACPI_AML_SIZE_LARGE (AML_RESOURCE_MEMORY24),
190     ACPI_AML_SIZE_LARGE (AML_RESOURCE_GENERIC_REGISTER),
191     0,
192     ACPI_AML_SIZE_LARGE (AML_RESOURCE_VENDOR_LARGE),
193     ACPI_AML_SIZE_LARGE (AML_RESOURCE_MEMORY32),
194     ACPI_AML_SIZE_LARGE (AML_RESOURCE_FIXED_MEMORY32),
195     ACPI_AML_SIZE_LARGE (AML_RESOURCE_ADDRESS32),
196     ACPI_AML_SIZE_LARGE (AML_RESOURCE_ADDRESS16),
197     ACPI_AML_SIZE_LARGE (AML_RESOURCE_EXTENDED_IRQ),
198     ACPI_AML_SIZE_LARGE (AML_RESOURCE_ADDRESS64),
199     ACPI_AML_SIZE_LARGE (AML_RESOURCE_EXTENDED_ADDRESS64),
200     ACPI_AML_SIZE_LARGE (AML_RESOURCE_GPIO),
201     ACPI_AML_SIZE_LARGE (AML_RESOURCE_PIN_FUNCTION),
202     ACPI_AML_SIZE_LARGE (AML_RESOURCE_COMMON_SERIALBUS),
203     ACPI_AML_SIZE_LARGE (AML_RESOURCE_PIN_CONFIG),
204     ACPI_AML_SIZE_LARGE (AML_RESOURCE_PIN_GROUP),
205     ACPI_AML_SIZE_LARGE (AML_RESOURCE_PIN_GROUP_FUNCTION),
206     ACPI_AML_SIZE_LARGE (AML_RESOURCE_PIN_GROUP_CONFIG),
207 };
208 
209 const UINT8                 AcpiGbl_ResourceAmlSerialBusSizes[] =
210 {
211     0,
212     ACPI_AML_SIZE_LARGE (AML_RESOURCE_I2C_SERIALBUS),
213     ACPI_AML_SIZE_LARGE (AML_RESOURCE_SPI_SERIALBUS),
214     ACPI_AML_SIZE_LARGE (AML_RESOURCE_UART_SERIALBUS),
215 };
216 
217 
218 /*
219  * Resource types, used to validate the resource length field.
220  * The length of fixed-length types must match exactly, variable
221  * lengths must meet the minimum required length, etc.
222  * Zero indicates a reserved (and therefore invalid) resource type.
223  */
224 static const UINT8          AcpiGbl_ResourceTypes[] =
225 {
226     /* Small descriptors */
227 
228     0,
229     0,
230     0,
231     0,
232     ACPI_SMALL_VARIABLE_LENGTH,     /* 04 IRQ */
233     ACPI_FIXED_LENGTH,              /* 05 DMA */
234     ACPI_SMALL_VARIABLE_LENGTH,     /* 06 StartDependentFunctions */
235     ACPI_FIXED_LENGTH,              /* 07 EndDependentFunctions */
236     ACPI_FIXED_LENGTH,              /* 08 IO */
237     ACPI_FIXED_LENGTH,              /* 09 FixedIO */
238     ACPI_FIXED_LENGTH,              /* 0A FixedDMA */
239     0,
240     0,
241     0,
242     ACPI_VARIABLE_LENGTH,           /* 0E VendorShort */
243     ACPI_FIXED_LENGTH,              /* 0F EndTag */
244 
245     /* Large descriptors */
246 
247     0,
248     ACPI_FIXED_LENGTH,              /* 01 Memory24 */
249     ACPI_FIXED_LENGTH,              /* 02 GenericRegister */
250     0,
251     ACPI_VARIABLE_LENGTH,           /* 04 VendorLong */
252     ACPI_FIXED_LENGTH,              /* 05 Memory32 */
253     ACPI_FIXED_LENGTH,              /* 06 Memory32Fixed */
254     ACPI_VARIABLE_LENGTH,           /* 07 Dword* address */
255     ACPI_VARIABLE_LENGTH,           /* 08 Word* address */
256     ACPI_VARIABLE_LENGTH,           /* 09 ExtendedIRQ */
257     ACPI_VARIABLE_LENGTH,           /* 0A Qword* address */
258     ACPI_FIXED_LENGTH,              /* 0B Extended* address */
259     ACPI_VARIABLE_LENGTH,           /* 0C Gpio* */
260     ACPI_VARIABLE_LENGTH,           /* 0D PinFunction */
261     ACPI_VARIABLE_LENGTH,           /* 0E *SerialBus */
262     ACPI_VARIABLE_LENGTH,           /* 0F PinConfig */
263     ACPI_VARIABLE_LENGTH,           /* 10 PinGroup */
264     ACPI_VARIABLE_LENGTH,           /* 11 PinGroupFunction */
265     ACPI_VARIABLE_LENGTH,           /* 12 PinGroupConfig */
266 };
267 
268 
269 /*******************************************************************************
270  *
271  * FUNCTION:    AcpiUtWalkAmlResources
272  *
273  * PARAMETERS:  WalkState           - Current walk info
274  * PARAMETERS:  Aml                 - Pointer to the raw AML resource template
275  *              AmlLength           - Length of the entire template
276  *              UserFunction        - Called once for each descriptor found. If
277  *                                    NULL, a pointer to the EndTag is returned
278  *              Context             - Passed to UserFunction
279  *
280  * RETURN:      Status
281  *
282  * DESCRIPTION: Walk a raw AML resource list(buffer). User function called
283  *              once for each resource found.
284  *
285  ******************************************************************************/
286 
287 ACPI_STATUS
288 AcpiUtWalkAmlResources (
289     ACPI_WALK_STATE         *WalkState,
290     UINT8                   *Aml,
291     ACPI_SIZE               AmlLength,
292     ACPI_WALK_AML_CALLBACK  UserFunction,
293     void                    **Context)
294 {
295     ACPI_STATUS             Status;
296     UINT8                   *EndAml;
297     UINT8                   ResourceIndex;
298     UINT32                  Length;
299     UINT32                  Offset = 0;
300     UINT8                   EndTag[2] = {0x79, 0x00};
301 
302 
303     ACPI_FUNCTION_TRACE (UtWalkAmlResources);
304 
305 
306     /*
307      * The absolute minimum resource template is one EndTag descriptor.
308      * However, we will treat a lone EndTag as just a simple buffer.
309      */
310     if (AmlLength <= sizeof (AML_RESOURCE_END_TAG))
311     {
312         return_ACPI_STATUS (AE_AML_NO_RESOURCE_END_TAG);
313     }
314 
315     /* Point to the end of the resource template buffer */
316 
317     EndAml = Aml + AmlLength;
318 
319     /* Walk the byte list, abort on any invalid descriptor type or length */
320 
321     while (Aml < EndAml)
322     {
323         /* Validate the Resource Type and Resource Length */
324 
325         Status = AcpiUtValidateResource (WalkState, Aml, &ResourceIndex);
326         if (ACPI_FAILURE (Status))
327         {
328             /*
329              * Exit on failure. Cannot continue because the descriptor
330              * length may be bogus also.
331              */
332             return_ACPI_STATUS (Status);
333         }
334 
335         /* Get the length of this descriptor */
336 
337         Length = AcpiUtGetDescriptorLength (Aml);
338 
339         /* Invoke the user function */
340 
341         if (UserFunction)
342         {
343             Status = UserFunction (
344                 Aml, Length, Offset, ResourceIndex, Context);
345             if (ACPI_FAILURE (Status))
346             {
347                 return_ACPI_STATUS (Status);
348             }
349         }
350 
351         /* An EndTag descriptor terminates this resource template */
352 
353         if (AcpiUtGetResourceType (Aml) == ACPI_RESOURCE_NAME_END_TAG)
354         {
355             /*
356              * There must be at least one more byte in the buffer for
357              * the 2nd byte of the EndTag
358              */
359             if ((Aml + 1) >= EndAml)
360             {
361                 return_ACPI_STATUS (AE_AML_NO_RESOURCE_END_TAG);
362             }
363 
364             /*
365              * The EndTag opcode must be followed by a zero byte.
366              * Although this byte is technically defined to be a checksum,
367              * in practice, all ASL compilers set this byte to zero.
368              */
369             if (*(Aml + 1) != 0)
370             {
371                 return_ACPI_STATUS (AE_AML_NO_RESOURCE_END_TAG);
372             }
373 
374             /* Return the pointer to the EndTag if requested */
375 
376             if (!UserFunction)
377             {
378                 *Context = Aml;
379             }
380 
381             /*
382              * Normal exit. Note: We allow the buffer to be larger than
383              * the resource template, as long as the END_TAG exists.
384              */
385             return_ACPI_STATUS (AE_OK);
386         }
387 
388         Aml += Length;
389         Offset += Length;
390     }
391 
392     /* Did not find an EndTag descriptor */
393 
394     if (UserFunction)
395     {
396         /* Insert an EndTag anyway. AcpiRsGetListLength always leaves room */
397 
398         (void) AcpiUtValidateResource (WalkState, EndTag, &ResourceIndex);
399         Status = UserFunction (EndTag, 2, Offset, ResourceIndex, Context);
400         if (ACPI_FAILURE (Status))
401         {
402             return_ACPI_STATUS (Status);
403         }
404     }
405 
406     return_ACPI_STATUS (AE_AML_NO_RESOURCE_END_TAG);
407 }
408 
409 
410 /*******************************************************************************
411  *
412  * FUNCTION:    AcpiUtValidateResource
413  *
414  * PARAMETERS:  WalkState           - Current walk info
415  *              Aml                 - Pointer to the raw AML resource descriptor
416  *              ReturnIndex         - Where the resource index is returned. NULL
417  *                                    if the index is not required.
418  *
419  * RETURN:      Status, and optionally the Index into the global resource tables
420  *
421  * DESCRIPTION: Validate an AML resource descriptor by checking the Resource
422  *              Type and Resource Length. Returns an index into the global
423  *              resource information/dispatch tables for later use.
424  *
425  ******************************************************************************/
426 
427 ACPI_STATUS
428 AcpiUtValidateResource (
429     ACPI_WALK_STATE         *WalkState,
430     void                    *Aml,
431     UINT8                   *ReturnIndex)
432 {
433     AML_RESOURCE            *AmlResource;
434     UINT8                   ResourceType;
435     UINT8                   ResourceIndex;
436     ACPI_RS_LENGTH          ResourceLength;
437     ACPI_RS_LENGTH          MinimumResourceLength;
438 
439 
440     ACPI_FUNCTION_ENTRY ();
441 
442 
443     /*
444      * 1) Validate the ResourceType field (Byte 0)
445      */
446     ResourceType = ACPI_GET8 (Aml);
447 
448     /*
449      * Byte 0 contains the descriptor name (Resource Type)
450      * Examine the large/small bit in the resource header
451      */
452     if (ResourceType & ACPI_RESOURCE_NAME_LARGE)
453     {
454         /* Verify the large resource type (name) against the max */
455 
456         if (ResourceType > ACPI_RESOURCE_NAME_LARGE_MAX)
457         {
458             goto InvalidResource;
459         }
460 
461         /*
462          * Large Resource Type -- bits 6:0 contain the name
463          * Translate range 0x80-0x8B to index range 0x10-0x1B
464          */
465         ResourceIndex = (UINT8) (ResourceType - 0x70);
466     }
467     else
468     {
469         /*
470          * Small Resource Type -- bits 6:3 contain the name
471          * Shift range to index range 0x00-0x0F
472          */
473         ResourceIndex = (UINT8)
474             ((ResourceType & ACPI_RESOURCE_NAME_SMALL_MASK) >> 3);
475     }
476 
477     /*
478      * Check validity of the resource type, via AcpiGbl_ResourceTypes.
479      * Zero indicates an invalid resource.
480      */
481     if (!AcpiGbl_ResourceTypes[ResourceIndex])
482     {
483         goto InvalidResource;
484     }
485 
486     /*
487      * Validate the ResourceLength field. This ensures that the length
488      * is at least reasonable, and guarantees that it is non-zero.
489      */
490     ResourceLength = AcpiUtGetResourceLength (Aml);
491     MinimumResourceLength = AcpiGbl_ResourceAmlSizes[ResourceIndex];
492 
493     /* Validate based upon the type of resource - fixed length or variable */
494 
495     switch (AcpiGbl_ResourceTypes[ResourceIndex])
496     {
497     case ACPI_FIXED_LENGTH:
498 
499         /* Fixed length resource, length must match exactly */
500 
501         if (ResourceLength != MinimumResourceLength)
502         {
503             goto BadResourceLength;
504         }
505         break;
506 
507     case ACPI_VARIABLE_LENGTH:
508 
509         /* Variable length resource, length must be at least the minimum */
510 
511         if (ResourceLength < MinimumResourceLength)
512         {
513             goto BadResourceLength;
514         }
515         break;
516 
517     case ACPI_SMALL_VARIABLE_LENGTH:
518 
519         /* Small variable length resource, length can be (Min) or (Min-1) */
520 
521         if ((ResourceLength > MinimumResourceLength) ||
522             (ResourceLength < (MinimumResourceLength - 1)))
523         {
524             goto BadResourceLength;
525         }
526         break;
527 
528     default:
529 
530         /* Shouldn't happen (because of validation earlier), but be sure */
531 
532         goto InvalidResource;
533     }
534 
535     AmlResource = ACPI_CAST_PTR (AML_RESOURCE, Aml);
536     if (ResourceType == ACPI_RESOURCE_NAME_SERIAL_BUS)
537     {
538         /* Validate the BusType field */
539 
540         if ((AmlResource->CommonSerialBus.Type == 0) ||
541             (AmlResource->CommonSerialBus.Type > AML_RESOURCE_MAX_SERIALBUSTYPE))
542         {
543             if (WalkState)
544             {
545                 ACPI_ERROR ((AE_INFO,
546                     "Invalid/unsupported SerialBus resource descriptor: BusType 0x%2.2X",
547                     AmlResource->CommonSerialBus.Type));
548             }
549             return (AE_AML_INVALID_RESOURCE_TYPE);
550         }
551     }
552 
553     /* Optionally return the resource table index */
554 
555     if (ReturnIndex)
556     {
557         *ReturnIndex = ResourceIndex;
558     }
559 
560     return (AE_OK);
561 
562 
563 InvalidResource:
564 
565     if (WalkState)
566     {
567         ACPI_ERROR ((AE_INFO,
568             "Invalid/unsupported resource descriptor: Type 0x%2.2X",
569             ResourceType));
570     }
571     return (AE_AML_INVALID_RESOURCE_TYPE);
572 
573 BadResourceLength:
574 
575     if (WalkState)
576     {
577         ACPI_ERROR ((AE_INFO,
578             "Invalid resource descriptor length: Type "
579             "0x%2.2X, Length 0x%4.4X, MinLength 0x%4.4X",
580             ResourceType, ResourceLength, MinimumResourceLength));
581     }
582     return (AE_AML_BAD_RESOURCE_LENGTH);
583 }
584 
585 
586 /*******************************************************************************
587  *
588  * FUNCTION:    AcpiUtGetResourceType
589  *
590  * PARAMETERS:  Aml             - Pointer to the raw AML resource descriptor
591  *
592  * RETURN:      The Resource Type with no extraneous bits (except the
593  *              Large/Small descriptor bit -- this is left alone)
594  *
595  * DESCRIPTION: Extract the Resource Type/Name from the first byte of
596  *              a resource descriptor.
597  *
598  ******************************************************************************/
599 
600 UINT8
601 AcpiUtGetResourceType (
602     void                    *Aml)
603 {
604     ACPI_FUNCTION_ENTRY ();
605 
606 
607     /*
608      * Byte 0 contains the descriptor name (Resource Type)
609      * Examine the large/small bit in the resource header
610      */
611     if (ACPI_GET8 (Aml) & ACPI_RESOURCE_NAME_LARGE)
612     {
613         /* Large Resource Type -- bits 6:0 contain the name */
614 
615         return (ACPI_GET8 (Aml));
616     }
617     else
618     {
619         /* Small Resource Type -- bits 6:3 contain the name */
620 
621         return ((UINT8) (ACPI_GET8 (Aml) & ACPI_RESOURCE_NAME_SMALL_MASK));
622     }
623 }
624 
625 
626 /*******************************************************************************
627  *
628  * FUNCTION:    AcpiUtGetResourceLength
629  *
630  * PARAMETERS:  Aml             - Pointer to the raw AML resource descriptor
631  *
632  * RETURN:      Byte Length
633  *
634  * DESCRIPTION: Get the "Resource Length" of a raw AML descriptor. By
635  *              definition, this does not include the size of the descriptor
636  *              header or the length field itself.
637  *
638  ******************************************************************************/
639 
640 UINT16
641 AcpiUtGetResourceLength (
642     void                    *Aml)
643 {
644     ACPI_RS_LENGTH          ResourceLength;
645 
646 
647     ACPI_FUNCTION_ENTRY ();
648 
649 
650     /*
651      * Byte 0 contains the descriptor name (Resource Type)
652      * Examine the large/small bit in the resource header
653      */
654     if (ACPI_GET8 (Aml) & ACPI_RESOURCE_NAME_LARGE)
655     {
656         /* Large Resource type -- bytes 1-2 contain the 16-bit length */
657 
658         ACPI_MOVE_16_TO_16 (&ResourceLength, ACPI_ADD_PTR (UINT8, Aml, 1));
659 
660     }
661     else
662     {
663         /* Small Resource type -- bits 2:0 of byte 0 contain the length */
664 
665         ResourceLength = (UINT16) (ACPI_GET8 (Aml) &
666             ACPI_RESOURCE_NAME_SMALL_LENGTH_MASK);
667     }
668 
669     return (ResourceLength);
670 }
671 
672 
673 /*******************************************************************************
674  *
675  * FUNCTION:    AcpiUtGetResourceHeaderLength
676  *
677  * PARAMETERS:  Aml             - Pointer to the raw AML resource descriptor
678  *
679  * RETURN:      Length of the AML header (depends on large/small descriptor)
680  *
681  * DESCRIPTION: Get the length of the header for this resource.
682  *
683  ******************************************************************************/
684 
685 UINT8
686 AcpiUtGetResourceHeaderLength (
687     void                    *Aml)
688 {
689     ACPI_FUNCTION_ENTRY ();
690 
691 
692     /* Examine the large/small bit in the resource header */
693 
694     if (ACPI_GET8 (Aml) & ACPI_RESOURCE_NAME_LARGE)
695     {
696         return (sizeof (AML_RESOURCE_LARGE_HEADER));
697     }
698     else
699     {
700         return (sizeof (AML_RESOURCE_SMALL_HEADER));
701     }
702 }
703 
704 
705 /*******************************************************************************
706  *
707  * FUNCTION:    AcpiUtGetDescriptorLength
708  *
709  * PARAMETERS:  Aml             - Pointer to the raw AML resource descriptor
710  *
711  * RETURN:      Byte length
712  *
713  * DESCRIPTION: Get the total byte length of a raw AML descriptor, including the
714  *              length of the descriptor header and the length field itself.
715  *              Used to walk descriptor lists.
716  *
717  ******************************************************************************/
718 
719 UINT32
720 AcpiUtGetDescriptorLength (
721     void                    *Aml)
722 {
723     ACPI_FUNCTION_ENTRY ();
724 
725 
726     /*
727      * Get the Resource Length (does not include header length) and add
728      * the header length (depends on if this is a small or large resource)
729      */
730     return (AcpiUtGetResourceLength (Aml) +
731         AcpiUtGetResourceHeaderLength (Aml));
732 }
733 
734 
735 /*******************************************************************************
736  *
737  * FUNCTION:    AcpiUtGetResourceEndTag
738  *
739  * PARAMETERS:  ObjDesc         - The resource template buffer object
740  *              EndTag          - Where the pointer to the EndTag is returned
741  *
742  * RETURN:      Status, pointer to the end tag
743  *
744  * DESCRIPTION: Find the EndTag resource descriptor in an AML resource template
745  *              Note: allows a buffer length of zero.
746  *
747  ******************************************************************************/
748 
749 ACPI_STATUS
750 AcpiUtGetResourceEndTag (
751     ACPI_OPERAND_OBJECT     *ObjDesc,
752     UINT8                   **EndTag)
753 {
754     ACPI_STATUS             Status;
755 
756 
757     ACPI_FUNCTION_TRACE (UtGetResourceEndTag);
758 
759 
760     /* Allow a buffer length of zero */
761 
762     if (!ObjDesc->Buffer.Length)
763     {
764         *EndTag = ObjDesc->Buffer.Pointer;
765         return_ACPI_STATUS (AE_OK);
766     }
767 
768     /* Validate the template and get a pointer to the EndTag */
769 
770     Status = AcpiUtWalkAmlResources (NULL, ObjDesc->Buffer.Pointer,
771         ObjDesc->Buffer.Length, NULL, (void **) EndTag);
772 
773     return_ACPI_STATUS (Status);
774 }
775