xref: /linux/drivers/acpi/acpica/exconvrt.c (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
1 /******************************************************************************
2  *
3  * Module Name: exconvrt - Object conversion routines
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2011, 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 		return_ACPI_STATUS(AE_TYPE);
103 	}
104 
105 	/*
106 	 * Convert the buffer/string to an integer. Note that both buffers and
107 	 * strings are treated as raw data - we don't convert ascii to hex for
108 	 * strings.
109 	 *
110 	 * There are two terminating conditions for the loop:
111 	 * 1) The size of an integer has been reached, or
112 	 * 2) The end of the buffer or string has been reached
113 	 */
114 	result = 0;
115 
116 	/* String conversion is different than Buffer conversion */
117 
118 	switch (obj_desc->common.type) {
119 	case ACPI_TYPE_STRING:
120 
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 		break;
165 	}
166 
167 	/* Create a new integer */
168 
169 	return_desc = acpi_ut_create_integer_object(result);
170 	if (!return_desc) {
171 		return_ACPI_STATUS(AE_NO_MEMORY);
172 	}
173 
174 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Converted value: %8.8X%8.8X\n",
175 			  ACPI_FORMAT_UINT64(result)));
176 
177 	/* Save the Result */
178 
179 	acpi_ex_truncate_for32bit_table(return_desc);
180 	*result_desc = return_desc;
181 	return_ACPI_STATUS(AE_OK);
182 }
183 
184 /*******************************************************************************
185  *
186  * FUNCTION:    acpi_ex_convert_to_buffer
187  *
188  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
189  *                                Integer, Buffer, or String
190  *              result_desc     - Where the new buffer object is returned
191  *
192  * RETURN:      Status
193  *
194  * DESCRIPTION: Convert an ACPI Object to a Buffer
195  *
196  ******************************************************************************/
197 
198 acpi_status
199 acpi_ex_convert_to_buffer(union acpi_operand_object *obj_desc,
200 			  union acpi_operand_object **result_desc)
201 {
202 	union acpi_operand_object *return_desc;
203 	u8 *new_buf;
204 
205 	ACPI_FUNCTION_TRACE_PTR(ex_convert_to_buffer, obj_desc);
206 
207 	switch (obj_desc->common.type) {
208 	case ACPI_TYPE_BUFFER:
209 
210 		/* No conversion necessary */
211 
212 		*result_desc = obj_desc;
213 		return_ACPI_STATUS(AE_OK);
214 
215 	case ACPI_TYPE_INTEGER:
216 
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 		ACPI_MEMCPY(new_buf,
231 			    &obj_desc->integer.value,
232 			    acpi_gbl_integer_byte_width);
233 		break;
234 
235 	case ACPI_TYPE_STRING:
236 
237 		/*
238 		 * Create a new Buffer object
239 		 * Size will be the string length
240 		 *
241 		 * NOTE: Add one to the string length to include the null terminator.
242 		 * The ACPI spec is unclear on this subject, but there is existing
243 		 * ASL/AML code that depends on the null being transferred to the new
244 		 * buffer.
245 		 */
246 		return_desc = acpi_ut_create_buffer_object((acpi_size)
247 							   obj_desc->string.
248 							   length + 1);
249 		if (!return_desc) {
250 			return_ACPI_STATUS(AE_NO_MEMORY);
251 		}
252 
253 		/* Copy the string to the buffer */
254 
255 		new_buf = return_desc->buffer.pointer;
256 		ACPI_STRNCPY((char *)new_buf, (char *)obj_desc->string.pointer,
257 			     obj_desc->string.length);
258 		break;
259 
260 	default:
261 		return_ACPI_STATUS(AE_TYPE);
262 	}
263 
264 	/* Mark buffer initialized */
265 
266 	return_desc->common.flags |= AOPOBJ_DATA_VALID;
267 	*result_desc = return_desc;
268 	return_ACPI_STATUS(AE_OK);
269 }
270 
271 /*******************************************************************************
272  *
273  * FUNCTION:    acpi_ex_convert_to_ascii
274  *
275  * PARAMETERS:  Integer         - Value to be converted
276  *              Base            - ACPI_STRING_DECIMAL or ACPI_STRING_HEX
277  *              String          - Where the string is returned
278  *              data_width      - Size of data item to be converted, in bytes
279  *
280  * RETURN:      Actual string length
281  *
282  * DESCRIPTION: Convert an ACPI Integer to a hex or decimal string
283  *
284  ******************************************************************************/
285 
286 static u32
287 acpi_ex_convert_to_ascii(u64 integer, u16 base, u8 *string, u8 data_width)
288 {
289 	u64 digit;
290 	u32 i;
291 	u32 j;
292 	u32 k = 0;
293 	u32 hex_length;
294 	u32 decimal_length;
295 	u32 remainder;
296 	u8 supress_zeros;
297 
298 	ACPI_FUNCTION_ENTRY();
299 
300 	switch (base) {
301 	case 10:
302 
303 		/* Setup max length for the decimal number */
304 
305 		switch (data_width) {
306 		case 1:
307 			decimal_length = ACPI_MAX8_DECIMAL_DIGITS;
308 			break;
309 
310 		case 4:
311 			decimal_length = ACPI_MAX32_DECIMAL_DIGITS;
312 			break;
313 
314 		case 8:
315 		default:
316 			decimal_length = ACPI_MAX64_DECIMAL_DIGITS;
317 			break;
318 		}
319 
320 		supress_zeros = TRUE;	/* No leading zeros */
321 		remainder = 0;
322 
323 		for (i = decimal_length; i > 0; i--) {
324 
325 			/* Divide by nth factor of 10 */
326 
327 			digit = integer;
328 			for (j = 0; j < i; j++) {
329 				(void)acpi_ut_short_divide(digit, 10, &digit,
330 							   &remainder);
331 			}
332 
333 			/* Handle leading zeros */
334 
335 			if (remainder != 0) {
336 				supress_zeros = FALSE;
337 			}
338 
339 			if (!supress_zeros) {
340 				string[k] = (u8) (ACPI_ASCII_ZERO + remainder);
341 				k++;
342 			}
343 		}
344 		break;
345 
346 	case 16:
347 
348 		/* hex_length: 2 ascii hex chars per data byte */
349 
350 		hex_length = ACPI_MUL_2(data_width);
351 		for (i = 0, j = (hex_length - 1); i < hex_length; i++, j--) {
352 
353 			/* Get one hex digit, most significant digits first */
354 
355 			string[k] =
356 			    (u8) acpi_ut_hex_to_ascii_char(integer,
357 							   ACPI_MUL_4(j));
358 			k++;
359 		}
360 		break;
361 
362 	default:
363 		return (0);
364 	}
365 
366 	/*
367 	 * Since leading zeros are suppressed, we must check for the case where
368 	 * the integer equals 0
369 	 *
370 	 * Finally, null terminate the string and return the length
371 	 */
372 	if (!k) {
373 		string[0] = ACPI_ASCII_ZERO;
374 		k = 1;
375 	}
376 
377 	string[k] = 0;
378 	return ((u32) k);
379 }
380 
381 /*******************************************************************************
382  *
383  * FUNCTION:    acpi_ex_convert_to_string
384  *
385  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
386  *                                Integer, Buffer, or String
387  *              result_desc     - Where the string object is returned
388  *              Type            - String flags (base and conversion type)
389  *
390  * RETURN:      Status
391  *
392  * DESCRIPTION: Convert an ACPI Object to a string
393  *
394  ******************************************************************************/
395 
396 acpi_status
397 acpi_ex_convert_to_string(union acpi_operand_object * obj_desc,
398 			  union acpi_operand_object ** result_desc, u32 type)
399 {
400 	union acpi_operand_object *return_desc;
401 	u8 *new_buf;
402 	u32 i;
403 	u32 string_length = 0;
404 	u16 base = 16;
405 	u8 separator = ',';
406 
407 	ACPI_FUNCTION_TRACE_PTR(ex_convert_to_string, obj_desc);
408 
409 	switch (obj_desc->common.type) {
410 	case ACPI_TYPE_STRING:
411 
412 		/* No conversion necessary */
413 
414 		*result_desc = obj_desc;
415 		return_ACPI_STATUS(AE_OK);
416 
417 	case ACPI_TYPE_INTEGER:
418 
419 		switch (type) {
420 		case ACPI_EXPLICIT_CONVERT_DECIMAL:
421 
422 			/* Make room for maximum decimal number */
423 
424 			string_length = ACPI_MAX_DECIMAL_DIGITS;
425 			base = 10;
426 			break;
427 
428 		default:
429 
430 			/* Two hex string characters for each integer byte */
431 
432 			string_length = ACPI_MUL_2(acpi_gbl_integer_byte_width);
433 			break;
434 		}
435 
436 		/*
437 		 * Create a new String
438 		 * Need enough space for one ASCII integer (plus null terminator)
439 		 */
440 		return_desc =
441 		    acpi_ut_create_string_object((acpi_size) string_length);
442 		if (!return_desc) {
443 			return_ACPI_STATUS(AE_NO_MEMORY);
444 		}
445 
446 		new_buf = return_desc->buffer.pointer;
447 
448 		/* Convert integer to string */
449 
450 		string_length =
451 		    acpi_ex_convert_to_ascii(obj_desc->integer.value, base,
452 					     new_buf,
453 					     acpi_gbl_integer_byte_width);
454 
455 		/* Null terminate at the correct place */
456 
457 		return_desc->string.length = string_length;
458 		new_buf[string_length] = 0;
459 		break;
460 
461 	case ACPI_TYPE_BUFFER:
462 
463 		/* Setup string length, base, and separator */
464 
465 		switch (type) {
466 		case ACPI_EXPLICIT_CONVERT_DECIMAL:	/* Used by to_decimal_string */
467 			/*
468 			 * From ACPI: "If Data is a buffer, it is converted to a string of
469 			 * decimal values separated by commas."
470 			 */
471 			base = 10;
472 
473 			/*
474 			 * Calculate the final string length. Individual string values
475 			 * are variable length (include separator for each)
476 			 */
477 			for (i = 0; i < obj_desc->buffer.length; i++) {
478 				if (obj_desc->buffer.pointer[i] >= 100) {
479 					string_length += 4;
480 				} else if (obj_desc->buffer.pointer[i] >= 10) {
481 					string_length += 3;
482 				} else {
483 					string_length += 2;
484 				}
485 			}
486 			break;
487 
488 		case ACPI_IMPLICIT_CONVERT_HEX:
489 			/*
490 			 * From the ACPI spec:
491 			 *"The entire contents of the buffer are converted to a string of
492 			 * two-character hexadecimal numbers, each separated by a space."
493 			 */
494 			separator = ' ';
495 			string_length = (obj_desc->buffer.length * 3);
496 			break;
497 
498 		case ACPI_EXPLICIT_CONVERT_HEX:	/* Used by to_hex_string */
499 			/*
500 			 * From ACPI: "If Data is a buffer, it is converted to a string of
501 			 * hexadecimal values separated by commas."
502 			 */
503 			string_length = (obj_desc->buffer.length * 3);
504 			break;
505 
506 		default:
507 			return_ACPI_STATUS(AE_BAD_PARAMETER);
508 		}
509 
510 		/*
511 		 * Create a new string object and string buffer
512 		 * (-1 because of extra separator included in string_length from above)
513 		 * Allow creation of zero-length strings from zero-length buffers.
514 		 */
515 		if (string_length) {
516 			string_length--;
517 		}
518 
519 		return_desc = acpi_ut_create_string_object((acpi_size)
520 							   string_length);
521 		if (!return_desc) {
522 			return_ACPI_STATUS(AE_NO_MEMORY);
523 		}
524 
525 		new_buf = return_desc->buffer.pointer;
526 
527 		/*
528 		 * Convert buffer bytes to hex or decimal values
529 		 * (separated by commas or spaces)
530 		 */
531 		for (i = 0; i < obj_desc->buffer.length; i++) {
532 			new_buf += acpi_ex_convert_to_ascii((u64) obj_desc->
533 							    buffer.pointer[i],
534 							    base, new_buf, 1);
535 			*new_buf++ = separator;	/* each separated by a comma or space */
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 		return_ACPI_STATUS(AE_TYPE);
550 	}
551 
552 	*result_desc = return_desc;
553 	return_ACPI_STATUS(AE_OK);
554 }
555 
556 /*******************************************************************************
557  *
558  * FUNCTION:    acpi_ex_convert_to_target_type
559  *
560  * PARAMETERS:  destination_type    - Current type of the destination
561  *              source_desc         - Source object to be converted.
562  *              result_desc         - Where the converted object is returned
563  *              walk_state          - Current method state
564  *
565  * RETURN:      Status
566  *
567  * DESCRIPTION: Implements "implicit conversion" rules for storing an object.
568  *
569  ******************************************************************************/
570 
571 acpi_status
572 acpi_ex_convert_to_target_type(acpi_object_type destination_type,
573 			       union acpi_operand_object *source_desc,
574 			       union acpi_operand_object **result_desc,
575 			       struct acpi_walk_state *walk_state)
576 {
577 	acpi_status status = AE_OK;
578 
579 	ACPI_FUNCTION_TRACE(ex_convert_to_target_type);
580 
581 	/* Default behavior */
582 
583 	*result_desc = source_desc;
584 
585 	/*
586 	 * If required by the target,
587 	 * perform implicit conversion on the source before we store it.
588 	 */
589 	switch (GET_CURRENT_ARG_TYPE(walk_state->op_info->runtime_args)) {
590 	case ARGI_SIMPLE_TARGET:
591 	case ARGI_FIXED_TARGET:
592 	case ARGI_INTEGER_REF:	/* Handles Increment, Decrement cases */
593 
594 		switch (destination_type) {
595 		case ACPI_TYPE_LOCAL_REGION_FIELD:
596 			/*
597 			 * Named field can always handle conversions
598 			 */
599 			break;
600 
601 		default:
602 			/* No conversion allowed for these types */
603 
604 			if (destination_type != source_desc->common.type) {
605 				ACPI_DEBUG_PRINT((ACPI_DB_INFO,
606 						  "Explicit operator, will store (%s) over existing type (%s)\n",
607 						  acpi_ut_get_object_type_name
608 						  (source_desc),
609 						  acpi_ut_get_type_name
610 						  (destination_type)));
611 				status = AE_TYPE;
612 			}
613 		}
614 		break;
615 
616 	case ARGI_TARGETREF:
617 
618 		switch (destination_type) {
619 		case ACPI_TYPE_INTEGER:
620 		case ACPI_TYPE_BUFFER_FIELD:
621 		case ACPI_TYPE_LOCAL_BANK_FIELD:
622 		case ACPI_TYPE_LOCAL_INDEX_FIELD:
623 			/*
624 			 * These types require an Integer operand. We can convert
625 			 * a Buffer or a String to an Integer if necessary.
626 			 */
627 			status =
628 			    acpi_ex_convert_to_integer(source_desc, result_desc,
629 						       16);
630 			break;
631 
632 		case ACPI_TYPE_STRING:
633 			/*
634 			 * The operand must be a String. We can convert an
635 			 * Integer or Buffer if necessary
636 			 */
637 			status =
638 			    acpi_ex_convert_to_string(source_desc, result_desc,
639 						      ACPI_IMPLICIT_CONVERT_HEX);
640 			break;
641 
642 		case ACPI_TYPE_BUFFER:
643 			/*
644 			 * The operand must be a Buffer. We can convert an
645 			 * Integer or String if necessary
646 			 */
647 			status =
648 			    acpi_ex_convert_to_buffer(source_desc, result_desc);
649 			break;
650 
651 		default:
652 			ACPI_ERROR((AE_INFO,
653 				    "Bad destination type during conversion: 0x%X",
654 				    destination_type));
655 			status = AE_AML_INTERNAL;
656 			break;
657 		}
658 		break;
659 
660 	case ARGI_REFERENCE:
661 		/*
662 		 * create_xxxx_field cases - we are storing the field object into the name
663 		 */
664 		break;
665 
666 	default:
667 		ACPI_ERROR((AE_INFO,
668 			    "Unknown Target type ID 0x%X AmlOpcode 0x%X DestType %s",
669 			    GET_CURRENT_ARG_TYPE(walk_state->op_info->
670 						 runtime_args),
671 			    walk_state->opcode,
672 			    acpi_ut_get_type_name(destination_type)));
673 		status = AE_AML_INTERNAL;
674 	}
675 
676 	/*
677 	 * Source-to-Target conversion semantics:
678 	 *
679 	 * If conversion to the target type cannot be performed, then simply
680 	 * overwrite the target with the new object and type.
681 	 */
682 	if (status == AE_TYPE) {
683 		status = AE_OK;
684 	}
685 
686 	return_ACPI_STATUS(status);
687 }
688