1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3 *
4 * Module Name: exconvrt - Object conversion routines
5 *
6 * Copyright (C) 2000 - 2021, Intel Corp.
7 *
8 *****************************************************************************/
9
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acinterp.h"
13 #include "amlcode.h"
14
15 #define _COMPONENT ACPI_EXECUTER
16 ACPI_MODULE_NAME("exconvrt")
17
18 /* Local prototypes */
19 static u32
20 acpi_ex_convert_to_ascii(u64 integer, u16 base, u8 *string, u8 max_length);
21
22 /*******************************************************************************
23 *
24 * FUNCTION: acpi_ex_convert_to_integer
25 *
26 * PARAMETERS: obj_desc - Object to be converted. Must be an
27 * Integer, Buffer, or String
28 * result_desc - Where the new Integer object is returned
29 * implicit_conversion - Used for string conversion
30 *
31 * RETURN: Status
32 *
33 * DESCRIPTION: Convert an ACPI Object to an integer.
34 *
35 ******************************************************************************/
36
37 acpi_status
acpi_ex_convert_to_integer(union acpi_operand_object * obj_desc,union acpi_operand_object ** result_desc,u32 implicit_conversion)38 acpi_ex_convert_to_integer(union acpi_operand_object *obj_desc,
39 union acpi_operand_object **result_desc,
40 u32 implicit_conversion)
41 {
42 union acpi_operand_object *return_desc;
43 u8 *pointer;
44 u64 result;
45 u32 i;
46 u32 count;
47
48 ACPI_FUNCTION_TRACE_PTR(ex_convert_to_integer, obj_desc);
49
50 switch (obj_desc->common.type) {
51 case ACPI_TYPE_INTEGER:
52
53 /* No conversion necessary */
54
55 *result_desc = obj_desc;
56 return_ACPI_STATUS(AE_OK);
57
58 case ACPI_TYPE_BUFFER:
59 case ACPI_TYPE_STRING:
60
61 /* Note: Takes advantage of common buffer/string fields */
62
63 pointer = obj_desc->buffer.pointer;
64 count = obj_desc->buffer.length;
65 break;
66
67 default:
68
69 return_ACPI_STATUS(AE_TYPE);
70 }
71
72 /*
73 * Convert the buffer/string to an integer. Note that both buffers and
74 * strings are treated as raw data - we don't convert ascii to hex for
75 * strings.
76 *
77 * There are two terminating conditions for the loop:
78 * 1) The size of an integer has been reached, or
79 * 2) The end of the buffer or string has been reached
80 */
81 result = 0;
82
83 /* String conversion is different than Buffer conversion */
84
85 switch (obj_desc->common.type) {
86 case ACPI_TYPE_STRING:
87 /*
88 * Convert string to an integer - for most cases, the string must be
89 * hexadecimal as per the ACPI specification. The only exception (as
90 * of ACPI 3.0) is that the to_integer() operator allows both decimal
91 * and hexadecimal strings (hex prefixed with "0x").
92 *
93 * Explicit conversion is used only by to_integer.
94 * All other string-to-integer conversions are implicit conversions.
95 */
96 if (implicit_conversion) {
97 result =
98 acpi_ut_implicit_strtoul64(ACPI_CAST_PTR
99 (char, pointer));
100 } else {
101 result =
102 acpi_ut_explicit_strtoul64(ACPI_CAST_PTR
103 (char, pointer));
104 }
105 break;
106
107 case ACPI_TYPE_BUFFER:
108
109 /* Check for zero-length buffer */
110
111 if (!count) {
112 return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
113 }
114
115 /* Transfer no more than an integer's worth of data */
116
117 if (count > acpi_gbl_integer_byte_width) {
118 count = acpi_gbl_integer_byte_width;
119 }
120
121 /*
122 * Convert buffer to an integer - we simply grab enough raw data
123 * from the buffer to fill an integer
124 */
125 for (i = 0; i < count; i++) {
126 /*
127 * Get next byte and shift it into the Result.
128 * Little endian is used, meaning that the first byte of the buffer
129 * is the LSB of the integer
130 */
131 result |= (((u64) pointer[i]) << (i * 8));
132 }
133 break;
134
135 default:
136
137 /* No other types can get here */
138
139 break;
140 }
141
142 /* Create a new integer */
143
144 return_desc = acpi_ut_create_integer_object(result);
145 if (!return_desc) {
146 return_ACPI_STATUS(AE_NO_MEMORY);
147 }
148
149 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Converted value: %8.8X%8.8X\n",
150 ACPI_FORMAT_UINT64(result)));
151
152 /* Save the Result */
153
154 (void)acpi_ex_truncate_for32bit_table(return_desc);
155 *result_desc = return_desc;
156 return_ACPI_STATUS(AE_OK);
157 }
158
159 /*******************************************************************************
160 *
161 * FUNCTION: acpi_ex_convert_to_buffer
162 *
163 * PARAMETERS: obj_desc - Object to be converted. Must be an
164 * Integer, Buffer, or String
165 * result_desc - Where the new buffer object is returned
166 *
167 * RETURN: Status
168 *
169 * DESCRIPTION: Convert an ACPI Object to a Buffer
170 *
171 ******************************************************************************/
172
173 acpi_status
acpi_ex_convert_to_buffer(union acpi_operand_object * obj_desc,union acpi_operand_object ** result_desc)174 acpi_ex_convert_to_buffer(union acpi_operand_object *obj_desc,
175 union acpi_operand_object **result_desc)
176 {
177 union acpi_operand_object *return_desc;
178 u8 *new_buf;
179
180 ACPI_FUNCTION_TRACE_PTR(ex_convert_to_buffer, obj_desc);
181
182 switch (obj_desc->common.type) {
183 case ACPI_TYPE_BUFFER:
184
185 /* No conversion necessary */
186
187 *result_desc = obj_desc;
188 return_ACPI_STATUS(AE_OK);
189
190 case ACPI_TYPE_INTEGER:
191 /*
192 * Create a new Buffer object.
193 * Need enough space for one integer
194 */
195 return_desc =
196 acpi_ut_create_buffer_object(acpi_gbl_integer_byte_width);
197 if (!return_desc) {
198 return_ACPI_STATUS(AE_NO_MEMORY);
199 }
200
201 /* Copy the integer to the buffer, LSB first */
202
203 new_buf = return_desc->buffer.pointer;
204 memcpy(new_buf, &obj_desc->integer.value,
205 acpi_gbl_integer_byte_width);
206 break;
207
208 case ACPI_TYPE_STRING:
209 /*
210 * Create a new Buffer object
211 * Size will be the string length
212 *
213 * NOTE: Add one to the string length to include the null terminator.
214 * The ACPI spec is unclear on this subject, but there is existing
215 * ASL/AML code that depends on the null being transferred to the new
216 * buffer.
217 */
218 return_desc = acpi_ut_create_buffer_object((acpi_size)
219 obj_desc->string.
220 length + 1);
221 if (!return_desc) {
222 return_ACPI_STATUS(AE_NO_MEMORY);
223 }
224
225 /* Copy the string to the buffer */
226
227 new_buf = return_desc->buffer.pointer;
228 strncpy((char *)new_buf, (char *)obj_desc->string.pointer,
229 obj_desc->string.length);
230 break;
231
232 default:
233
234 return_ACPI_STATUS(AE_TYPE);
235 }
236
237 /* Mark buffer initialized */
238
239 return_desc->common.flags |= AOPOBJ_DATA_VALID;
240 *result_desc = return_desc;
241 return_ACPI_STATUS(AE_OK);
242 }
243
244 /*******************************************************************************
245 *
246 * FUNCTION: acpi_ex_convert_to_ascii
247 *
248 * PARAMETERS: integer - Value to be converted
249 * base - ACPI_STRING_DECIMAL or ACPI_STRING_HEX
250 * string - Where the string is returned
251 * data_width - Size of data item to be converted, in bytes
252 *
253 * RETURN: Actual string length
254 *
255 * DESCRIPTION: Convert an ACPI Integer to a hex or decimal string
256 *
257 ******************************************************************************/
258
259 static u32
acpi_ex_convert_to_ascii(u64 integer,u16 base,u8 * string,u8 data_width)260 acpi_ex_convert_to_ascii(u64 integer, u16 base, u8 *string, u8 data_width)
261 {
262 u64 digit;
263 u32 i;
264 u32 j;
265 u32 k = 0;
266 u32 hex_length;
267 u32 decimal_length;
268 u32 remainder;
269 u8 supress_zeros;
270
271 ACPI_FUNCTION_ENTRY();
272
273 switch (base) {
274 case 10:
275
276 /* Setup max length for the decimal number */
277
278 switch (data_width) {
279 case 1:
280
281 decimal_length = ACPI_MAX8_DECIMAL_DIGITS;
282 break;
283
284 case 4:
285
286 decimal_length = ACPI_MAX32_DECIMAL_DIGITS;
287 break;
288
289 case 8:
290 default:
291
292 decimal_length = ACPI_MAX64_DECIMAL_DIGITS;
293 break;
294 }
295
296 supress_zeros = TRUE; /* No leading zeros */
297 remainder = 0;
298
299 for (i = decimal_length; i > 0; i--) {
300
301 /* Divide by nth factor of 10 */
302
303 digit = integer;
304 for (j = 0; j < i; j++) {
305 (void)acpi_ut_short_divide(digit, 10, &digit,
306 &remainder);
307 }
308
309 /* Handle leading zeros */
310
311 if (remainder != 0) {
312 supress_zeros = FALSE;
313 }
314
315 if (!supress_zeros) {
316 string[k] = (u8) (ACPI_ASCII_ZERO + remainder);
317 k++;
318 }
319 }
320 break;
321
322 case 16:
323
324 /* hex_length: 2 ascii hex chars per data byte */
325
326 hex_length = (data_width * 2);
327 for (i = 0, j = (hex_length - 1); i < hex_length; i++, j--) {
328
329 /* Get one hex digit, most significant digits first */
330
331 string[k] = (u8)
332 acpi_ut_hex_to_ascii_char(integer, ACPI_MUL_4(j));
333 k++;
334 }
335 break;
336
337 default:
338 return (0);
339 }
340
341 /*
342 * Since leading zeros are suppressed, we must check for the case where
343 * the integer equals 0
344 *
345 * Finally, null terminate the string and return the length
346 */
347 if (!k) {
348 string[0] = ACPI_ASCII_ZERO;
349 k = 1;
350 }
351
352 string[k] = 0;
353 return ((u32) k);
354 }
355
356 /*******************************************************************************
357 *
358 * FUNCTION: acpi_ex_convert_to_string
359 *
360 * PARAMETERS: obj_desc - Object to be converted. Must be an
361 * Integer, Buffer, or String
362 * result_desc - Where the string object is returned
363 * type - String flags (base and conversion type)
364 *
365 * RETURN: Status
366 *
367 * DESCRIPTION: Convert an ACPI Object to a string. Supports both implicit
368 * and explicit conversions and related rules.
369 *
370 ******************************************************************************/
371
372 acpi_status
acpi_ex_convert_to_string(union acpi_operand_object * obj_desc,union acpi_operand_object ** result_desc,u32 type)373 acpi_ex_convert_to_string(union acpi_operand_object * obj_desc,
374 union acpi_operand_object ** result_desc, u32 type)
375 {
376 union acpi_operand_object *return_desc;
377 u8 *new_buf;
378 u32 i;
379 u32 string_length = 0;
380 u16 base = 16;
381 u8 separator = ',';
382
383 ACPI_FUNCTION_TRACE_PTR(ex_convert_to_string, obj_desc);
384
385 switch (obj_desc->common.type) {
386 case ACPI_TYPE_STRING:
387
388 /* No conversion necessary */
389
390 *result_desc = obj_desc;
391 return_ACPI_STATUS(AE_OK);
392
393 case ACPI_TYPE_INTEGER:
394
395 switch (type) {
396 case ACPI_EXPLICIT_CONVERT_DECIMAL:
397 /*
398 * From to_decimal_string, integer source.
399 *
400 * Make room for the maximum decimal number size
401 */
402 string_length = ACPI_MAX_DECIMAL_DIGITS;
403 base = 10;
404 break;
405
406 default:
407
408 /* Two hex string characters for each integer byte */
409
410 string_length = ACPI_MUL_2(acpi_gbl_integer_byte_width);
411 break;
412 }
413
414 /*
415 * Create a new String
416 * Need enough space for one ASCII integer (plus null terminator)
417 */
418 return_desc =
419 acpi_ut_create_string_object((acpi_size)string_length);
420 if (!return_desc) {
421 return_ACPI_STATUS(AE_NO_MEMORY);
422 }
423
424 new_buf = return_desc->buffer.pointer;
425
426 /* Convert integer to string */
427
428 string_length =
429 acpi_ex_convert_to_ascii(obj_desc->integer.value, base,
430 new_buf,
431 acpi_gbl_integer_byte_width);
432
433 /* Null terminate at the correct place */
434
435 return_desc->string.length = string_length;
436 new_buf[string_length] = 0;
437 break;
438
439 case ACPI_TYPE_BUFFER:
440
441 /* Setup string length, base, and separator */
442
443 switch (type) {
444 case ACPI_EXPLICIT_CONVERT_DECIMAL: /* Used by to_decimal_string */
445 /*
446 * Explicit conversion from the to_decimal_string ASL operator.
447 *
448 * From ACPI: "If the input is a buffer, it is converted to a
449 * a string of decimal values separated by commas."
450 */
451 base = 10;
452
453 /*
454 * Calculate the final string length. Individual string values
455 * are variable length (include separator for each)
456 */
457 for (i = 0; i < obj_desc->buffer.length; i++) {
458 if (obj_desc->buffer.pointer[i] >= 100) {
459 string_length += 4;
460 } else if (obj_desc->buffer.pointer[i] >= 10) {
461 string_length += 3;
462 } else {
463 string_length += 2;
464 }
465 }
466 break;
467
468 case ACPI_IMPLICIT_CONVERT_HEX:
469 /*
470 * Implicit buffer-to-string conversion
471 *
472 * From the ACPI spec:
473 * "The entire contents of the buffer are converted to a string of
474 * two-character hexadecimal numbers, each separated by a space."
475 *
476 * Each hex number is prefixed with 0x (11/2018)
477 */
478 separator = ' ';
479 string_length = (obj_desc->buffer.length * 5);
480 break;
481
482 case ACPI_EXPLICIT_CONVERT_HEX:
483 /*
484 * Explicit conversion from the to_hex_string ASL operator.
485 *
486 * From ACPI: "If Data is a buffer, it is converted to a string of
487 * hexadecimal values separated by commas."
488 *
489 * Each hex number is prefixed with 0x (11/2018)
490 */
491 separator = ',';
492 string_length = (obj_desc->buffer.length * 5);
493 break;
494
495 default:
496 return_ACPI_STATUS(AE_BAD_PARAMETER);
497 }
498
499 /*
500 * Create a new string object and string buffer
501 * (-1 because of extra separator included in string_length from above)
502 * Allow creation of zero-length strings from zero-length buffers.
503 */
504 if (string_length) {
505 string_length--;
506 }
507
508 return_desc =
509 acpi_ut_create_string_object((acpi_size)string_length);
510 if (!return_desc) {
511 return_ACPI_STATUS(AE_NO_MEMORY);
512 }
513
514 new_buf = return_desc->buffer.pointer;
515
516 /*
517 * Convert buffer bytes to hex or decimal values
518 * (separated by commas or spaces)
519 */
520 for (i = 0; i < obj_desc->buffer.length; i++) {
521 if (base == 16) {
522
523 /* Emit 0x prefix for explicit/implicit hex conversion */
524
525 *new_buf++ = '0';
526 *new_buf++ = 'x';
527 }
528
529 new_buf += acpi_ex_convert_to_ascii((u64) obj_desc->
530 buffer.pointer[i],
531 base, new_buf, 1);
532
533 /* Each digit is separated by either a comma or space */
534
535 *new_buf++ = separator;
536 }
537
538 /*
539 * Null terminate the string
540 * (overwrites final comma/space from above)
541 */
542 if (obj_desc->buffer.length) {
543 new_buf--;
544 }
545 *new_buf = 0;
546 break;
547
548 default:
549
550 return_ACPI_STATUS(AE_TYPE);
551 }
552
553 *result_desc = return_desc;
554 return_ACPI_STATUS(AE_OK);
555 }
556
557 /*******************************************************************************
558 *
559 * FUNCTION: acpi_ex_convert_to_target_type
560 *
561 * PARAMETERS: destination_type - Current type of the destination
562 * source_desc - Source object to be converted.
563 * result_desc - Where the converted object is returned
564 * walk_state - Current method state
565 *
566 * RETURN: Status
567 *
568 * DESCRIPTION: Implements "implicit conversion" rules for storing an object.
569 *
570 ******************************************************************************/
571
572 acpi_status
acpi_ex_convert_to_target_type(acpi_object_type destination_type,union acpi_operand_object * source_desc,union acpi_operand_object ** result_desc,struct acpi_walk_state * walk_state)573 acpi_ex_convert_to_target_type(acpi_object_type destination_type,
574 union acpi_operand_object *source_desc,
575 union acpi_operand_object **result_desc,
576 struct acpi_walk_state *walk_state)
577 {
578 acpi_status status = AE_OK;
579
580 ACPI_FUNCTION_TRACE(ex_convert_to_target_type);
581
582 /* Default behavior */
583
584 *result_desc = source_desc;
585
586 /*
587 * If required by the target,
588 * perform implicit conversion on the source before we store it.
589 */
590 switch (GET_CURRENT_ARG_TYPE(walk_state->op_info->runtime_args)) {
591 case ARGI_SIMPLE_TARGET:
592 case ARGI_FIXED_TARGET:
593 case ARGI_INTEGER_REF: /* Handles Increment, Decrement cases */
594
595 switch (destination_type) {
596 case ACPI_TYPE_LOCAL_REGION_FIELD:
597 /*
598 * Named field can always handle conversions
599 */
600 break;
601
602 default:
603
604 /* No conversion allowed for these types */
605
606 if (destination_type != source_desc->common.type) {
607 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
608 "Explicit operator, will store (%s) over existing type (%s)\n",
609 acpi_ut_get_object_type_name
610 (source_desc),
611 acpi_ut_get_type_name
612 (destination_type)));
613 status = AE_TYPE;
614 }
615 }
616 break;
617
618 case ARGI_TARGETREF:
619 case ARGI_STORE_TARGET:
620
621 switch (destination_type) {
622 case ACPI_TYPE_INTEGER:
623 case ACPI_TYPE_BUFFER_FIELD:
624 case ACPI_TYPE_LOCAL_BANK_FIELD:
625 case ACPI_TYPE_LOCAL_INDEX_FIELD:
626 /*
627 * These types require an Integer operand. We can convert
628 * a Buffer or a String to an Integer if necessary.
629 */
630 status =
631 acpi_ex_convert_to_integer(source_desc, result_desc,
632 ACPI_IMPLICIT_CONVERSION);
633 break;
634
635 case ACPI_TYPE_STRING:
636 /*
637 * The operand must be a String. We can convert an
638 * Integer or Buffer if necessary
639 */
640 status =
641 acpi_ex_convert_to_string(source_desc, result_desc,
642 ACPI_IMPLICIT_CONVERT_HEX);
643 break;
644
645 case ACPI_TYPE_BUFFER:
646 /*
647 * The operand must be a Buffer. We can convert an
648 * Integer or String if necessary
649 */
650 status =
651 acpi_ex_convert_to_buffer(source_desc, result_desc);
652 break;
653
654 default:
655
656 ACPI_ERROR((AE_INFO,
657 "Bad destination type during conversion: 0x%X",
658 destination_type));
659 status = AE_AML_INTERNAL;
660 break;
661 }
662 break;
663
664 case ARGI_REFERENCE:
665 /*
666 * create_xxxx_field cases - we are storing the field object into the name
667 */
668 break;
669
670 default:
671
672 ACPI_ERROR((AE_INFO,
673 "Unknown Target type ID 0x%X AmlOpcode 0x%X DestType %s",
674 GET_CURRENT_ARG_TYPE(walk_state->op_info->
675 runtime_args),
676 walk_state->opcode,
677 acpi_ut_get_type_name(destination_type)));
678 status = AE_AML_INTERNAL;
679 }
680
681 /*
682 * Source-to-Target conversion semantics:
683 *
684 * If conversion to the target type cannot be performed, then simply
685 * overwrite the target with the new object and type.
686 */
687 if (status == AE_TYPE) {
688 status = AE_OK;
689 }
690
691 return_ACPI_STATUS(status);
692 }
693