xref: /freebsd/sys/contrib/dev/acpica/components/executer/exconvrt.c (revision cfd6422a5217410fbd66f7a7a8a64d9d85e61229)
1 /******************************************************************************
2  *
3  * Module Name: exconvrt - Object conversion routines
4  *
5  *****************************************************************************/
6 
7 /******************************************************************************
8  *
9  * 1. Copyright Notice
10  *
11  * Some or all of this work - Copyright (c) 1999 - 2020, 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/acinterp.h>
155 #include <contrib/dev/acpica/include/amlcode.h>
156 
157 
158 #define _COMPONENT          ACPI_EXECUTER
159         ACPI_MODULE_NAME    ("exconvrt")
160 
161 /* Local prototypes */
162 
163 static UINT32
164 AcpiExConvertToAscii (
165     UINT64                  Integer,
166     UINT16                  Base,
167     UINT8                   *String,
168     UINT8                   MaxLength);
169 
170 
171 /*******************************************************************************
172  *
173  * FUNCTION:    AcpiExConvertToInteger
174  *
175  * PARAMETERS:  ObjDesc             - Object to be converted. Must be an
176  *                                    Integer, Buffer, or String
177  *              ResultDesc          - Where the new Integer object is returned
178  *              ImplicitConversion  - Used for string conversion
179  *
180  * RETURN:      Status
181  *
182  * DESCRIPTION: Convert an ACPI Object to an integer.
183  *
184  ******************************************************************************/
185 
186 ACPI_STATUS
187 AcpiExConvertToInteger (
188     ACPI_OPERAND_OBJECT     *ObjDesc,
189     ACPI_OPERAND_OBJECT     **ResultDesc,
190     UINT32                  ImplicitConversion)
191 {
192     ACPI_OPERAND_OBJECT     *ReturnDesc;
193     UINT8                   *Pointer;
194     UINT64                  Result;
195     UINT32                  i;
196     UINT32                  Count;
197 
198 
199     ACPI_FUNCTION_TRACE_PTR (ExConvertToInteger, ObjDesc);
200 
201 
202     switch (ObjDesc->Common.Type)
203     {
204     case ACPI_TYPE_INTEGER:
205 
206         /* No conversion necessary */
207 
208         *ResultDesc = ObjDesc;
209         return_ACPI_STATUS (AE_OK);
210 
211     case ACPI_TYPE_BUFFER:
212     case ACPI_TYPE_STRING:
213 
214         /* Note: Takes advantage of common buffer/string fields */
215 
216         Pointer = ObjDesc->Buffer.Pointer;
217         Count   = ObjDesc->Buffer.Length;
218         break;
219 
220     default:
221 
222         return_ACPI_STATUS (AE_TYPE);
223     }
224 
225     /*
226      * Convert the buffer/string to an integer. Note that both buffers and
227      * strings are treated as raw data - we don't convert ascii to hex for
228      * strings.
229      *
230      * There are two terminating conditions for the loop:
231      * 1) The size of an integer has been reached, or
232      * 2) The end of the buffer or string has been reached
233      */
234     Result = 0;
235 
236     /* String conversion is different than Buffer conversion */
237 
238     switch (ObjDesc->Common.Type)
239     {
240     case ACPI_TYPE_STRING:
241         /*
242          * Convert string to an integer - for most cases, the string must be
243          * hexadecimal as per the ACPI specification. The only exception (as
244          * of ACPI 3.0) is that the ToInteger() operator allows both decimal
245          * and hexadecimal strings (hex prefixed with "0x").
246          *
247          * Explicit conversion is used only by ToInteger.
248          * All other string-to-integer conversions are implicit conversions.
249          */
250         if (ImplicitConversion)
251         {
252             Result = AcpiUtImplicitStrtoul64 (ACPI_CAST_PTR (char, Pointer));
253         }
254         else
255         {
256             Result = AcpiUtExplicitStrtoul64 (ACPI_CAST_PTR (char, Pointer));
257         }
258         break;
259 
260     case ACPI_TYPE_BUFFER:
261 
262         /* Check for zero-length buffer */
263 
264         if (!Count)
265         {
266             return_ACPI_STATUS (AE_AML_BUFFER_LIMIT);
267         }
268 
269         /* Transfer no more than an integer's worth of data */
270 
271         if (Count > AcpiGbl_IntegerByteWidth)
272         {
273             Count = AcpiGbl_IntegerByteWidth;
274         }
275 
276         /*
277          * Convert buffer to an integer - we simply grab enough raw data
278          * from the buffer to fill an integer
279          */
280         for (i = 0; i < Count; i++)
281         {
282             /*
283              * Get next byte and shift it into the Result.
284              * Little endian is used, meaning that the first byte of the buffer
285              * is the LSB of the integer
286              */
287             Result |= (((UINT64) Pointer[i]) << (i * 8));
288         }
289         break;
290 
291     default:
292 
293         /* No other types can get here */
294 
295         break;
296     }
297 
298     /* Create a new integer */
299 
300     ReturnDesc = AcpiUtCreateIntegerObject (Result);
301     if (!ReturnDesc)
302     {
303         return_ACPI_STATUS (AE_NO_MEMORY);
304     }
305 
306     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Converted value: %8.8X%8.8X\n",
307         ACPI_FORMAT_UINT64 (Result)));
308 
309     /* Save the Result */
310 
311     (void) AcpiExTruncateFor32bitTable (ReturnDesc);
312     *ResultDesc = ReturnDesc;
313     return_ACPI_STATUS (AE_OK);
314 }
315 
316 
317 /*******************************************************************************
318  *
319  * FUNCTION:    AcpiExConvertToBuffer
320  *
321  * PARAMETERS:  ObjDesc         - Object to be converted. Must be an
322  *                                Integer, Buffer, or String
323  *              ResultDesc      - Where the new buffer object is returned
324  *
325  * RETURN:      Status
326  *
327  * DESCRIPTION: Convert an ACPI Object to a Buffer
328  *
329  ******************************************************************************/
330 
331 ACPI_STATUS
332 AcpiExConvertToBuffer (
333     ACPI_OPERAND_OBJECT     *ObjDesc,
334     ACPI_OPERAND_OBJECT     **ResultDesc)
335 {
336     ACPI_OPERAND_OBJECT     *ReturnDesc;
337     UINT8                   *NewBuf;
338 
339 
340     ACPI_FUNCTION_TRACE_PTR (ExConvertToBuffer, ObjDesc);
341 
342 
343     switch (ObjDesc->Common.Type)
344     {
345     case ACPI_TYPE_BUFFER:
346 
347         /* No conversion necessary */
348 
349         *ResultDesc = ObjDesc;
350         return_ACPI_STATUS (AE_OK);
351 
352 
353     case ACPI_TYPE_INTEGER:
354         /*
355          * Create a new Buffer object.
356          * Need enough space for one integer
357          */
358         ReturnDesc = AcpiUtCreateBufferObject (AcpiGbl_IntegerByteWidth);
359         if (!ReturnDesc)
360         {
361             return_ACPI_STATUS (AE_NO_MEMORY);
362         }
363 
364         /* Copy the integer to the buffer, LSB first */
365 
366         NewBuf = ReturnDesc->Buffer.Pointer;
367         memcpy (NewBuf, &ObjDesc->Integer.Value, AcpiGbl_IntegerByteWidth);
368         break;
369 
370     case ACPI_TYPE_STRING:
371         /*
372          * Create a new Buffer object
373          * Size will be the string length
374          *
375          * NOTE: Add one to the string length to include the null terminator.
376          * The ACPI spec is unclear on this subject, but there is existing
377          * ASL/AML code that depends on the null being transferred to the new
378          * buffer.
379          */
380         ReturnDesc = AcpiUtCreateBufferObject ((ACPI_SIZE)
381             ObjDesc->String.Length + 1);
382         if (!ReturnDesc)
383         {
384             return_ACPI_STATUS (AE_NO_MEMORY);
385         }
386 
387         /* Copy the string to the buffer */
388 
389         NewBuf = ReturnDesc->Buffer.Pointer;
390         strncpy ((char *) NewBuf, (char *) ObjDesc->String.Pointer,
391             ObjDesc->String.Length);
392         break;
393 
394     default:
395 
396         return_ACPI_STATUS (AE_TYPE);
397     }
398 
399     /* Mark buffer initialized */
400 
401     ReturnDesc->Common.Flags |= AOPOBJ_DATA_VALID;
402     *ResultDesc = ReturnDesc;
403     return_ACPI_STATUS (AE_OK);
404 }
405 
406 
407 /*******************************************************************************
408  *
409  * FUNCTION:    AcpiExConvertToAscii
410  *
411  * PARAMETERS:  Integer         - Value to be converted
412  *              Base            - ACPI_STRING_DECIMAL or ACPI_STRING_HEX
413  *              String          - Where the string is returned
414  *              DataWidth       - Size of data item to be converted, in bytes
415  *
416  * RETURN:      Actual string length
417  *
418  * DESCRIPTION: Convert an ACPI Integer to a hex or decimal string
419  *
420  ******************************************************************************/
421 
422 static UINT32
423 AcpiExConvertToAscii (
424     UINT64                  Integer,
425     UINT16                  Base,
426     UINT8                   *String,
427     UINT8                   DataWidth)
428 {
429     UINT64                  Digit;
430     UINT32                  i;
431     UINT32                  j;
432     UINT32                  k = 0;
433     UINT32                  HexLength;
434     UINT32                  DecimalLength;
435     UINT32                  Remainder;
436     BOOLEAN                 SupressZeros;
437 
438 
439     ACPI_FUNCTION_ENTRY ();
440 
441 
442     switch (Base)
443     {
444     case 10:
445 
446         /* Setup max length for the decimal number */
447 
448         switch (DataWidth)
449         {
450         case 1:
451 
452             DecimalLength = ACPI_MAX8_DECIMAL_DIGITS;
453             break;
454 
455         case 4:
456 
457             DecimalLength = ACPI_MAX32_DECIMAL_DIGITS;
458             break;
459 
460         case 8:
461         default:
462 
463             DecimalLength = ACPI_MAX64_DECIMAL_DIGITS;
464             break;
465         }
466 
467         SupressZeros = TRUE;     /* No leading zeros */
468         Remainder = 0;
469 
470         for (i = DecimalLength; i > 0; i--)
471         {
472             /* Divide by nth factor of 10 */
473 
474             Digit = Integer;
475             for (j = 0; j < i; j++)
476             {
477                 (void) AcpiUtShortDivide (Digit, 10, &Digit, &Remainder);
478             }
479 
480             /* Handle leading zeros */
481 
482             if (Remainder != 0)
483             {
484                 SupressZeros = FALSE;
485             }
486 
487             if (!SupressZeros)
488             {
489                 String[k] = (UINT8) (ACPI_ASCII_ZERO + Remainder);
490                 k++;
491             }
492         }
493         break;
494 
495     case 16:
496 
497         /* HexLength: 2 ascii hex chars per data byte */
498 
499         HexLength = (DataWidth * 2);
500         for (i = 0, j = (HexLength-1); i < HexLength; i++, j--)
501         {
502             /* Get one hex digit, most significant digits first */
503 
504             String[k] = (UINT8)
505                 AcpiUtHexToAsciiChar (Integer, ACPI_MUL_4 (j));
506             k++;
507         }
508         break;
509 
510     default:
511         return (0);
512     }
513 
514     /*
515      * Since leading zeros are suppressed, we must check for the case where
516      * the integer equals 0
517      *
518      * Finally, null terminate the string and return the length
519      */
520     if (!k)
521     {
522         String [0] = ACPI_ASCII_ZERO;
523         k = 1;
524     }
525 
526     String [k] = 0;
527     return ((UINT32) k);
528 }
529 
530 
531 /*******************************************************************************
532  *
533  * FUNCTION:    AcpiExConvertToString
534  *
535  * PARAMETERS:  ObjDesc         - Object to be converted. Must be an
536  *                                Integer, Buffer, or String
537  *              ResultDesc      - Where the string object is returned
538  *              Type            - String flags (base and conversion type)
539  *
540  * RETURN:      Status
541  *
542  * DESCRIPTION: Convert an ACPI Object to a string. Supports both implicit
543  *              and explicit conversions and related rules.
544  *
545  ******************************************************************************/
546 
547 ACPI_STATUS
548 AcpiExConvertToString (
549     ACPI_OPERAND_OBJECT     *ObjDesc,
550     ACPI_OPERAND_OBJECT     **ResultDesc,
551     UINT32                  Type)
552 {
553     ACPI_OPERAND_OBJECT     *ReturnDesc;
554     UINT8                   *NewBuf;
555     UINT32                  i;
556     UINT32                  StringLength = 0;
557     UINT16                  Base = 16;
558     UINT8                   Separator = ',';
559 
560 
561     ACPI_FUNCTION_TRACE_PTR (ExConvertToString, ObjDesc);
562 
563 
564     switch (ObjDesc->Common.Type)
565     {
566     case ACPI_TYPE_STRING:
567 
568         /* No conversion necessary */
569 
570         *ResultDesc = ObjDesc;
571         return_ACPI_STATUS (AE_OK);
572 
573     case ACPI_TYPE_INTEGER:
574 
575         switch (Type)
576         {
577         case ACPI_EXPLICIT_CONVERT_DECIMAL:
578             /*
579              * From ToDecimalString, integer source.
580              *
581              * Make room for the maximum decimal number size
582              */
583             StringLength = ACPI_MAX_DECIMAL_DIGITS;
584             Base = 10;
585             break;
586 
587         default:
588 
589             /* Two hex string characters for each integer byte */
590 
591             StringLength = ACPI_MUL_2 (AcpiGbl_IntegerByteWidth);
592             break;
593         }
594 
595         /*
596          * Create a new String
597          * Need enough space for one ASCII integer (plus null terminator)
598          */
599         ReturnDesc = AcpiUtCreateStringObject ((ACPI_SIZE) StringLength);
600         if (!ReturnDesc)
601         {
602             return_ACPI_STATUS (AE_NO_MEMORY);
603         }
604 
605         NewBuf = ReturnDesc->Buffer.Pointer;
606 
607         /* Convert integer to string */
608 
609         StringLength = AcpiExConvertToAscii (
610             ObjDesc->Integer.Value, Base, NewBuf, AcpiGbl_IntegerByteWidth);
611 
612         /* Null terminate at the correct place */
613 
614         ReturnDesc->String.Length = StringLength;
615         NewBuf [StringLength] = 0;
616         break;
617 
618     case ACPI_TYPE_BUFFER:
619 
620         /* Setup string length, base, and separator */
621 
622         switch (Type)
623         {
624         case ACPI_EXPLICIT_CONVERT_DECIMAL: /* Used by ToDecimalString */
625             /*
626              * Explicit conversion from the ToDecimalString ASL operator.
627              *
628              * From ACPI: "If the input is a buffer, it is converted to a
629              * a string of decimal values separated by commas."
630              */
631             Base = 10;
632 
633             /*
634              * Calculate the final string length. Individual string values
635              * are variable length (include separator for each)
636              */
637             for (i = 0; i < ObjDesc->Buffer.Length; i++)
638             {
639                 if (ObjDesc->Buffer.Pointer[i] >= 100)
640                 {
641                     StringLength += 4;
642                 }
643                 else if (ObjDesc->Buffer.Pointer[i] >= 10)
644                 {
645                     StringLength += 3;
646                 }
647                 else
648                 {
649                     StringLength += 2;
650                 }
651             }
652             break;
653 
654         case ACPI_IMPLICIT_CONVERT_HEX:
655             /*
656              * Implicit buffer-to-string conversion
657              *
658              * From the ACPI spec:
659              * "The entire contents of the buffer are converted to a string of
660              * two-character hexadecimal numbers, each separated by a space."
661              *
662              * Each hex number is prefixed with 0x (11/2018)
663              */
664             Separator = ' ';
665             StringLength = (ObjDesc->Buffer.Length * 5);
666             break;
667 
668         case ACPI_EXPLICIT_CONVERT_HEX:
669             /*
670              * Explicit conversion from the ToHexString ASL operator.
671              *
672              * From ACPI: "If Data is a buffer, it is converted to a string of
673              * hexadecimal values separated by commas."
674              *
675              * Each hex number is prefixed with 0x (11/2018)
676              */
677             Separator = ',';
678             StringLength = (ObjDesc->Buffer.Length * 5);
679             break;
680 
681         default:
682             return_ACPI_STATUS (AE_BAD_PARAMETER);
683         }
684 
685         /*
686          * Create a new string object and string buffer
687          * (-1 because of extra separator included in StringLength from above)
688          * Allow creation of zero-length strings from zero-length buffers.
689          */
690         if (StringLength)
691         {
692             StringLength--;
693         }
694 
695         ReturnDesc = AcpiUtCreateStringObject ((ACPI_SIZE) StringLength);
696         if (!ReturnDesc)
697         {
698             return_ACPI_STATUS (AE_NO_MEMORY);
699         }
700 
701         NewBuf = ReturnDesc->Buffer.Pointer;
702 
703         /*
704          * Convert buffer bytes to hex or decimal values
705          * (separated by commas or spaces)
706          */
707         for (i = 0; i < ObjDesc->Buffer.Length; i++)
708         {
709             if (Base == 16)
710             {
711                 /* Emit 0x prefix for explicit/implicit hex conversion */
712 
713                 *NewBuf++ = '0';
714                 *NewBuf++ = 'x';
715             }
716 
717             NewBuf += AcpiExConvertToAscii (
718                 (UINT64) ObjDesc->Buffer.Pointer[i], Base, NewBuf, 1);
719 
720             /* Each digit is separated by either a comma or space */
721 
722             *NewBuf++ = Separator;
723         }
724 
725         /*
726          * Null terminate the string
727          * (overwrites final comma/space from above)
728          */
729         if (ObjDesc->Buffer.Length)
730         {
731             NewBuf--;
732         }
733         *NewBuf = 0;
734         break;
735 
736     default:
737 
738         return_ACPI_STATUS (AE_TYPE);
739     }
740 
741     *ResultDesc = ReturnDesc;
742     return_ACPI_STATUS (AE_OK);
743 }
744 
745 
746 /*******************************************************************************
747  *
748  * FUNCTION:    AcpiExConvertToTargetType
749  *
750  * PARAMETERS:  DestinationType     - Current type of the destination
751  *              SourceDesc          - Source object to be converted.
752  *              ResultDesc          - Where the converted object is returned
753  *              WalkState           - Current method state
754  *
755  * RETURN:      Status
756  *
757  * DESCRIPTION: Implements "implicit conversion" rules for storing an object.
758  *
759  ******************************************************************************/
760 
761 ACPI_STATUS
762 AcpiExConvertToTargetType (
763     ACPI_OBJECT_TYPE        DestinationType,
764     ACPI_OPERAND_OBJECT     *SourceDesc,
765     ACPI_OPERAND_OBJECT     **ResultDesc,
766     ACPI_WALK_STATE         *WalkState)
767 {
768     ACPI_STATUS             Status = AE_OK;
769 
770 
771     ACPI_FUNCTION_TRACE (ExConvertToTargetType);
772 
773 
774     /* Default behavior */
775 
776     *ResultDesc = SourceDesc;
777 
778     /*
779      * If required by the target,
780      * perform implicit conversion on the source before we store it.
781      */
782     switch (GET_CURRENT_ARG_TYPE (WalkState->OpInfo->RuntimeArgs))
783     {
784     case ARGI_SIMPLE_TARGET:
785     case ARGI_FIXED_TARGET:
786     case ARGI_INTEGER_REF:      /* Handles Increment, Decrement cases */
787 
788         switch (DestinationType)
789         {
790         case ACPI_TYPE_LOCAL_REGION_FIELD:
791             /*
792              * Named field can always handle conversions
793              */
794             break;
795 
796         default:
797 
798             /* No conversion allowed for these types */
799 
800             if (DestinationType != SourceDesc->Common.Type)
801             {
802                 ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
803                     "Explicit operator, will store (%s) over existing type (%s)\n",
804                     AcpiUtGetObjectTypeName (SourceDesc),
805                     AcpiUtGetTypeName (DestinationType)));
806                 Status = AE_TYPE;
807             }
808         }
809         break;
810 
811     case ARGI_TARGETREF:
812     case ARGI_STORE_TARGET:
813 
814         switch (DestinationType)
815         {
816         case ACPI_TYPE_INTEGER:
817         case ACPI_TYPE_BUFFER_FIELD:
818         case ACPI_TYPE_LOCAL_BANK_FIELD:
819         case ACPI_TYPE_LOCAL_INDEX_FIELD:
820             /*
821              * These types require an Integer operand. We can convert
822              * a Buffer or a String to an Integer if necessary.
823              */
824             Status = AcpiExConvertToInteger (SourceDesc, ResultDesc,
825                 ACPI_IMPLICIT_CONVERSION);
826             break;
827 
828         case ACPI_TYPE_STRING:
829             /*
830              * The operand must be a String. We can convert an
831              * Integer or Buffer if necessary
832              */
833             Status = AcpiExConvertToString (SourceDesc, ResultDesc,
834                 ACPI_IMPLICIT_CONVERT_HEX);
835             break;
836 
837         case ACPI_TYPE_BUFFER:
838             /*
839              * The operand must be a Buffer. We can convert an
840              * Integer or String if necessary
841              */
842             Status = AcpiExConvertToBuffer (SourceDesc, ResultDesc);
843             break;
844 
845         default:
846 
847             ACPI_ERROR ((AE_INFO,
848                 "Bad destination type during conversion: 0x%X",
849                 DestinationType));
850             Status = AE_AML_INTERNAL;
851             break;
852         }
853         break;
854 
855     case ARGI_REFERENCE:
856         /*
857          * CreateXxxxField cases - we are storing the field object into the name
858          */
859         break;
860 
861     default:
862 
863         ACPI_ERROR ((AE_INFO,
864             "Unknown Target type ID 0x%X AmlOpcode 0x%X DestType %s",
865             GET_CURRENT_ARG_TYPE (WalkState->OpInfo->RuntimeArgs),
866             WalkState->Opcode, AcpiUtGetTypeName (DestinationType)));
867         Status = AE_AML_INTERNAL;
868     }
869 
870     /*
871      * Source-to-Target conversion semantics:
872      *
873      * If conversion to the target type cannot be performed, then simply
874      * overwrite the target with the new object and type.
875      */
876     if (Status == AE_TYPE)
877     {
878         Status = AE_OK;
879     }
880 
881     return_ACPI_STATUS (Status);
882 }
883