xref: /linux/drivers/acpi/acpica/exconvrt.c (revision c0e297dc61f8d4453e07afbea1fa8d0e67cd4a34)
1 /******************************************************************************
2  *
3  * Module Name: exconvrt - Object conversion routines
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2015, 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 "acinterp.h"
47 #include "amlcode.h"
48 
49 #define _COMPONENT          ACPI_EXECUTER
50 ACPI_MODULE_NAME("exconvrt")
51 
52 /* Local prototypes */
53 static u32
54 acpi_ex_convert_to_ascii(u64 integer, u16 base, u8 *string, u8 max_length);
55 
56 /*******************************************************************************
57  *
58  * FUNCTION:    acpi_ex_convert_to_integer
59  *
60  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
61  *                                Integer, Buffer, or String
62  *              result_desc     - Where the new Integer object is returned
63  *              flags           - Used for string conversion
64  *
65  * RETURN:      Status
66  *
67  * DESCRIPTION: Convert an ACPI Object to an integer.
68  *
69  ******************************************************************************/
70 
71 acpi_status
72 acpi_ex_convert_to_integer(union acpi_operand_object *obj_desc,
73 			   union acpi_operand_object **result_desc, u32 flags)
74 {
75 	union acpi_operand_object *return_desc;
76 	u8 *pointer;
77 	u64 result;
78 	u32 i;
79 	u32 count;
80 	acpi_status status;
81 
82 	ACPI_FUNCTION_TRACE_PTR(ex_convert_to_integer, obj_desc);
83 
84 	switch (obj_desc->common.type) {
85 	case ACPI_TYPE_INTEGER:
86 
87 		/* No conversion necessary */
88 
89 		*result_desc = obj_desc;
90 		return_ACPI_STATUS(AE_OK);
91 
92 	case ACPI_TYPE_BUFFER:
93 	case ACPI_TYPE_STRING:
94 
95 		/* Note: Takes advantage of common buffer/string fields */
96 
97 		pointer = obj_desc->buffer.pointer;
98 		count = obj_desc->buffer.length;
99 		break;
100 
101 	default:
102 
103 		return_ACPI_STATUS(AE_TYPE);
104 	}
105 
106 	/*
107 	 * Convert the buffer/string to an integer. Note that both buffers and
108 	 * strings are treated as raw data - we don't convert ascii to hex for
109 	 * strings.
110 	 *
111 	 * There are two terminating conditions for the loop:
112 	 * 1) The size of an integer has been reached, or
113 	 * 2) The end of the buffer or string has been reached
114 	 */
115 	result = 0;
116 
117 	/* String conversion is different than Buffer conversion */
118 
119 	switch (obj_desc->common.type) {
120 	case ACPI_TYPE_STRING:
121 		/*
122 		 * Convert string to an integer - for most cases, the string must be
123 		 * hexadecimal as per the ACPI specification. The only exception (as
124 		 * of ACPI 3.0) is that the to_integer() operator allows both decimal
125 		 * and hexadecimal strings (hex prefixed with "0x").
126 		 */
127 		status = acpi_ut_strtoul64((char *)pointer, flags, &result);
128 		if (ACPI_FAILURE(status)) {
129 			return_ACPI_STATUS(status);
130 		}
131 		break;
132 
133 	case ACPI_TYPE_BUFFER:
134 
135 		/* Check for zero-length buffer */
136 
137 		if (!count) {
138 			return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
139 		}
140 
141 		/* Transfer no more than an integer's worth of data */
142 
143 		if (count > acpi_gbl_integer_byte_width) {
144 			count = acpi_gbl_integer_byte_width;
145 		}
146 
147 		/*
148 		 * Convert buffer to an integer - we simply grab enough raw data
149 		 * from the buffer to fill an integer
150 		 */
151 		for (i = 0; i < count; i++) {
152 			/*
153 			 * Get next byte and shift it into the Result.
154 			 * Little endian is used, meaning that the first byte of the buffer
155 			 * is the LSB of the integer
156 			 */
157 			result |= (((u64) pointer[i]) << (i * 8));
158 		}
159 		break;
160 
161 	default:
162 
163 		/* No other types can get here */
164 
165 		break;
166 	}
167 
168 	/* Create a new integer */
169 
170 	return_desc = acpi_ut_create_integer_object(result);
171 	if (!return_desc) {
172 		return_ACPI_STATUS(AE_NO_MEMORY);
173 	}
174 
175 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Converted value: %8.8X%8.8X\n",
176 			  ACPI_FORMAT_UINT64(result)));
177 
178 	/* Save the Result */
179 
180 	(void)acpi_ex_truncate_for32bit_table(return_desc);
181 	*result_desc = return_desc;
182 	return_ACPI_STATUS(AE_OK);
183 }
184 
185 /*******************************************************************************
186  *
187  * FUNCTION:    acpi_ex_convert_to_buffer
188  *
189  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
190  *                                Integer, Buffer, or String
191  *              result_desc     - Where the new buffer object is returned
192  *
193  * RETURN:      Status
194  *
195  * DESCRIPTION: Convert an ACPI Object to a Buffer
196  *
197  ******************************************************************************/
198 
199 acpi_status
200 acpi_ex_convert_to_buffer(union acpi_operand_object *obj_desc,
201 			  union acpi_operand_object **result_desc)
202 {
203 	union acpi_operand_object *return_desc;
204 	u8 *new_buf;
205 
206 	ACPI_FUNCTION_TRACE_PTR(ex_convert_to_buffer, obj_desc);
207 
208 	switch (obj_desc->common.type) {
209 	case ACPI_TYPE_BUFFER:
210 
211 		/* No conversion necessary */
212 
213 		*result_desc = obj_desc;
214 		return_ACPI_STATUS(AE_OK);
215 
216 	case ACPI_TYPE_INTEGER:
217 		/*
218 		 * Create a new Buffer object.
219 		 * Need enough space for one integer
220 		 */
221 		return_desc =
222 		    acpi_ut_create_buffer_object(acpi_gbl_integer_byte_width);
223 		if (!return_desc) {
224 			return_ACPI_STATUS(AE_NO_MEMORY);
225 		}
226 
227 		/* Copy the integer to the buffer, LSB first */
228 
229 		new_buf = return_desc->buffer.pointer;
230 		memcpy(new_buf,
231 		       &obj_desc->integer.value, acpi_gbl_integer_byte_width);
232 		break;
233 
234 	case ACPI_TYPE_STRING:
235 		/*
236 		 * Create a new Buffer object
237 		 * Size will be the string length
238 		 *
239 		 * NOTE: Add one to the string length to include the null terminator.
240 		 * The ACPI spec is unclear on this subject, but there is existing
241 		 * ASL/AML code that depends on the null being transferred to the new
242 		 * buffer.
243 		 */
244 		return_desc = acpi_ut_create_buffer_object((acpi_size)
245 							   obj_desc->string.
246 							   length + 1);
247 		if (!return_desc) {
248 			return_ACPI_STATUS(AE_NO_MEMORY);
249 		}
250 
251 		/* Copy the string to the buffer */
252 
253 		new_buf = return_desc->buffer.pointer;
254 		strncpy((char *)new_buf, (char *)obj_desc->string.pointer,
255 			obj_desc->string.length);
256 		break;
257 
258 	default:
259 
260 		return_ACPI_STATUS(AE_TYPE);
261 	}
262 
263 	/* Mark buffer initialized */
264 
265 	return_desc->common.flags |= AOPOBJ_DATA_VALID;
266 	*result_desc = return_desc;
267 	return_ACPI_STATUS(AE_OK);
268 }
269 
270 /*******************************************************************************
271  *
272  * FUNCTION:    acpi_ex_convert_to_ascii
273  *
274  * PARAMETERS:  integer         - Value to be converted
275  *              base            - ACPI_STRING_DECIMAL or ACPI_STRING_HEX
276  *              string          - Where the string is returned
277  *              data_width      - Size of data item to be converted, in bytes
278  *
279  * RETURN:      Actual string length
280  *
281  * DESCRIPTION: Convert an ACPI Integer to a hex or decimal string
282  *
283  ******************************************************************************/
284 
285 static u32
286 acpi_ex_convert_to_ascii(u64 integer, u16 base, u8 *string, u8 data_width)
287 {
288 	u64 digit;
289 	u32 i;
290 	u32 j;
291 	u32 k = 0;
292 	u32 hex_length;
293 	u32 decimal_length;
294 	u32 remainder;
295 	u8 supress_zeros;
296 
297 	ACPI_FUNCTION_ENTRY();
298 
299 	switch (base) {
300 	case 10:
301 
302 		/* Setup max length for the decimal number */
303 
304 		switch (data_width) {
305 		case 1:
306 
307 			decimal_length = ACPI_MAX8_DECIMAL_DIGITS;
308 			break;
309 
310 		case 4:
311 
312 			decimal_length = ACPI_MAX32_DECIMAL_DIGITS;
313 			break;
314 
315 		case 8:
316 		default:
317 
318 			decimal_length = ACPI_MAX64_DECIMAL_DIGITS;
319 			break;
320 		}
321 
322 		supress_zeros = TRUE;	/* No leading zeros */
323 		remainder = 0;
324 
325 		for (i = decimal_length; i > 0; i--) {
326 
327 			/* Divide by nth factor of 10 */
328 
329 			digit = integer;
330 			for (j = 0; j < i; j++) {
331 				(void)acpi_ut_short_divide(digit, 10, &digit,
332 							   &remainder);
333 			}
334 
335 			/* Handle leading zeros */
336 
337 			if (remainder != 0) {
338 				supress_zeros = FALSE;
339 			}
340 
341 			if (!supress_zeros) {
342 				string[k] = (u8) (ACPI_ASCII_ZERO + remainder);
343 				k++;
344 			}
345 		}
346 		break;
347 
348 	case 16:
349 
350 		/* hex_length: 2 ascii hex chars per data byte */
351 
352 		hex_length = ACPI_MUL_2(data_width);
353 		for (i = 0, j = (hex_length - 1); i < hex_length; i++, j--) {
354 
355 			/* Get one hex digit, most significant digits first */
356 
357 			string[k] =
358 			    (u8) acpi_ut_hex_to_ascii_char(integer,
359 							   ACPI_MUL_4(j));
360 			k++;
361 		}
362 		break;
363 
364 	default:
365 		return (0);
366 	}
367 
368 	/*
369 	 * Since leading zeros are suppressed, we must check for the case where
370 	 * the integer equals 0
371 	 *
372 	 * Finally, null terminate the string and return the length
373 	 */
374 	if (!k) {
375 		string[0] = ACPI_ASCII_ZERO;
376 		k = 1;
377 	}
378 
379 	string[k] = 0;
380 	return ((u32) k);
381 }
382 
383 /*******************************************************************************
384  *
385  * FUNCTION:    acpi_ex_convert_to_string
386  *
387  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
388  *                                Integer, Buffer, or String
389  *              result_desc     - Where the string object is returned
390  *              type            - String flags (base and conversion type)
391  *
392  * RETURN:      Status
393  *
394  * DESCRIPTION: Convert an ACPI Object to a string
395  *
396  ******************************************************************************/
397 
398 acpi_status
399 acpi_ex_convert_to_string(union acpi_operand_object * obj_desc,
400 			  union acpi_operand_object ** result_desc, u32 type)
401 {
402 	union acpi_operand_object *return_desc;
403 	u8 *new_buf;
404 	u32 i;
405 	u32 string_length = 0;
406 	u16 base = 16;
407 	u8 separator = ',';
408 
409 	ACPI_FUNCTION_TRACE_PTR(ex_convert_to_string, obj_desc);
410 
411 	switch (obj_desc->common.type) {
412 	case ACPI_TYPE_STRING:
413 
414 		/* No conversion necessary */
415 
416 		*result_desc = obj_desc;
417 		return_ACPI_STATUS(AE_OK);
418 
419 	case ACPI_TYPE_INTEGER:
420 
421 		switch (type) {
422 		case ACPI_EXPLICIT_CONVERT_DECIMAL:
423 
424 			/* Make room for maximum decimal number */
425 
426 			string_length = ACPI_MAX_DECIMAL_DIGITS;
427 			base = 10;
428 			break;
429 
430 		default:
431 
432 			/* Two hex string characters for each integer byte */
433 
434 			string_length = ACPI_MUL_2(acpi_gbl_integer_byte_width);
435 			break;
436 		}
437 
438 		/*
439 		 * Create a new String
440 		 * Need enough space for one ASCII integer (plus null terminator)
441 		 */
442 		return_desc =
443 		    acpi_ut_create_string_object((acpi_size) string_length);
444 		if (!return_desc) {
445 			return_ACPI_STATUS(AE_NO_MEMORY);
446 		}
447 
448 		new_buf = return_desc->buffer.pointer;
449 
450 		/* Convert integer to string */
451 
452 		string_length =
453 		    acpi_ex_convert_to_ascii(obj_desc->integer.value, base,
454 					     new_buf,
455 					     acpi_gbl_integer_byte_width);
456 
457 		/* Null terminate at the correct place */
458 
459 		return_desc->string.length = string_length;
460 		new_buf[string_length] = 0;
461 		break;
462 
463 	case ACPI_TYPE_BUFFER:
464 
465 		/* Setup string length, base, and separator */
466 
467 		switch (type) {
468 		case ACPI_EXPLICIT_CONVERT_DECIMAL:	/* Used by to_decimal_string */
469 			/*
470 			 * From ACPI: "If Data is a buffer, it is converted to a string of
471 			 * decimal values separated by commas."
472 			 */
473 			base = 10;
474 
475 			/*
476 			 * Calculate the final string length. Individual string values
477 			 * are variable length (include separator for each)
478 			 */
479 			for (i = 0; i < obj_desc->buffer.length; i++) {
480 				if (obj_desc->buffer.pointer[i] >= 100) {
481 					string_length += 4;
482 				} else if (obj_desc->buffer.pointer[i] >= 10) {
483 					string_length += 3;
484 				} else {
485 					string_length += 2;
486 				}
487 			}
488 			break;
489 
490 		case ACPI_IMPLICIT_CONVERT_HEX:
491 			/*
492 			 * From the ACPI spec:
493 			 *"The entire contents of the buffer are converted to a string of
494 			 * two-character hexadecimal numbers, each separated by a space."
495 			 */
496 			separator = ' ';
497 			string_length = (obj_desc->buffer.length * 3);
498 			break;
499 
500 		case ACPI_EXPLICIT_CONVERT_HEX:	/* Used by to_hex_string */
501 			/*
502 			 * From ACPI: "If Data is a buffer, it is converted to a string of
503 			 * hexadecimal values separated by commas."
504 			 */
505 			string_length = (obj_desc->buffer.length * 3);
506 			break;
507 
508 		default:
509 			return_ACPI_STATUS(AE_BAD_PARAMETER);
510 		}
511 
512 		/*
513 		 * Create a new string object and string buffer
514 		 * (-1 because of extra separator included in string_length from above)
515 		 * Allow creation of zero-length strings from zero-length buffers.
516 		 */
517 		if (string_length) {
518 			string_length--;
519 		}
520 
521 		return_desc =
522 		    acpi_ut_create_string_object((acpi_size) string_length);
523 		if (!return_desc) {
524 			return_ACPI_STATUS(AE_NO_MEMORY);
525 		}
526 
527 		new_buf = return_desc->buffer.pointer;
528 
529 		/*
530 		 * Convert buffer bytes to hex or decimal values
531 		 * (separated by commas or spaces)
532 		 */
533 		for (i = 0; i < obj_desc->buffer.length; i++) {
534 			new_buf += acpi_ex_convert_to_ascii((u64) obj_desc->
535 							    buffer.pointer[i],
536 							    base, new_buf, 1);
537 			*new_buf++ = separator;	/* each separated by a comma or space */
538 		}
539 
540 		/*
541 		 * Null terminate the string
542 		 * (overwrites final comma/space from above)
543 		 */
544 		if (obj_desc->buffer.length) {
545 			new_buf--;
546 		}
547 		*new_buf = 0;
548 		break;
549 
550 	default:
551 
552 		return_ACPI_STATUS(AE_TYPE);
553 	}
554 
555 	*result_desc = return_desc;
556 	return_ACPI_STATUS(AE_OK);
557 }
558 
559 /*******************************************************************************
560  *
561  * FUNCTION:    acpi_ex_convert_to_target_type
562  *
563  * PARAMETERS:  destination_type    - Current type of the destination
564  *              source_desc         - Source object to be converted.
565  *              result_desc         - Where the converted object is returned
566  *              walk_state          - Current method state
567  *
568  * RETURN:      Status
569  *
570  * DESCRIPTION: Implements "implicit conversion" rules for storing an object.
571  *
572  ******************************************************************************/
573 
574 acpi_status
575 acpi_ex_convert_to_target_type(acpi_object_type destination_type,
576 			       union acpi_operand_object *source_desc,
577 			       union acpi_operand_object **result_desc,
578 			       struct acpi_walk_state *walk_state)
579 {
580 	acpi_status status = AE_OK;
581 
582 	ACPI_FUNCTION_TRACE(ex_convert_to_target_type);
583 
584 	/* Default behavior */
585 
586 	*result_desc = source_desc;
587 
588 	/*
589 	 * If required by the target,
590 	 * perform implicit conversion on the source before we store it.
591 	 */
592 	switch (GET_CURRENT_ARG_TYPE(walk_state->op_info->runtime_args)) {
593 	case ARGI_SIMPLE_TARGET:
594 	case ARGI_FIXED_TARGET:
595 	case ARGI_INTEGER_REF:	/* Handles Increment, Decrement cases */
596 
597 		switch (destination_type) {
598 		case ACPI_TYPE_LOCAL_REGION_FIELD:
599 			/*
600 			 * Named field can always handle conversions
601 			 */
602 			break;
603 
604 		default:
605 
606 			/* No conversion allowed for these types */
607 
608 			if (destination_type != source_desc->common.type) {
609 				ACPI_DEBUG_PRINT((ACPI_DB_INFO,
610 						  "Explicit operator, will store (%s) over existing type (%s)\n",
611 						  acpi_ut_get_object_type_name
612 						  (source_desc),
613 						  acpi_ut_get_type_name
614 						  (destination_type)));
615 				status = AE_TYPE;
616 			}
617 		}
618 		break;
619 
620 	case ARGI_TARGETREF:
621 
622 		switch (destination_type) {
623 		case ACPI_TYPE_INTEGER:
624 		case ACPI_TYPE_BUFFER_FIELD:
625 		case ACPI_TYPE_LOCAL_BANK_FIELD:
626 		case ACPI_TYPE_LOCAL_INDEX_FIELD:
627 			/*
628 			 * These types require an Integer operand. We can convert
629 			 * a Buffer or a String to an Integer if necessary.
630 			 */
631 			status =
632 			    acpi_ex_convert_to_integer(source_desc, result_desc,
633 						       16);
634 			break;
635 
636 		case ACPI_TYPE_STRING:
637 			/*
638 			 * The operand must be a String. We can convert an
639 			 * Integer or Buffer if necessary
640 			 */
641 			status =
642 			    acpi_ex_convert_to_string(source_desc, result_desc,
643 						      ACPI_IMPLICIT_CONVERT_HEX);
644 			break;
645 
646 		case ACPI_TYPE_BUFFER:
647 			/*
648 			 * The operand must be a Buffer. We can convert an
649 			 * Integer or String if necessary
650 			 */
651 			status =
652 			    acpi_ex_convert_to_buffer(source_desc, result_desc);
653 			break;
654 
655 		default:
656 
657 			ACPI_ERROR((AE_INFO,
658 				    "Bad destination type during conversion: 0x%X",
659 				    destination_type));
660 			status = AE_AML_INTERNAL;
661 			break;
662 		}
663 		break;
664 
665 	case ARGI_REFERENCE:
666 		/*
667 		 * create_xxxx_field cases - we are storing the field object into the name
668 		 */
669 		break;
670 
671 	default:
672 
673 		ACPI_ERROR((AE_INFO,
674 			    "Unknown Target type ID 0x%X AmlOpcode 0x%X DestType %s",
675 			    GET_CURRENT_ARG_TYPE(walk_state->op_info->
676 						 runtime_args),
677 			    walk_state->opcode,
678 			    acpi_ut_get_type_name(destination_type)));
679 		status = AE_AML_INTERNAL;
680 	}
681 
682 	/*
683 	 * Source-to-Target conversion semantics:
684 	 *
685 	 * If conversion to the target type cannot be performed, then simply
686 	 * overwrite the target with the new object and type.
687 	 */
688 	if (status == AE_TYPE) {
689 		status = AE_OK;
690 	}
691 
692 	return_ACPI_STATUS(status);
693 }
694