xref: /openbmc/linux/drivers/acpi/acpica/exconvrt.c (revision a09d2831)
1 /******************************************************************************
2  *
3  * Module Name: exconvrt - Object conversion routines
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2008, 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(acpi_integer integer,
55 			 u16 base, u8 * string, u8 max_length);
56 
57 /*******************************************************************************
58  *
59  * FUNCTION:    acpi_ex_convert_to_integer
60  *
61  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
62  *                                Integer, Buffer, or String
63  *              result_desc     - Where the new Integer object is returned
64  *              Flags           - Used for string conversion
65  *
66  * RETURN:      Status
67  *
68  * DESCRIPTION: Convert an ACPI Object to an integer.
69  *
70  ******************************************************************************/
71 
72 acpi_status
73 acpi_ex_convert_to_integer(union acpi_operand_object *obj_desc,
74 			   union acpi_operand_object **result_desc, u32 flags)
75 {
76 	union acpi_operand_object *return_desc;
77 	u8 *pointer;
78 	acpi_integer result;
79 	u32 i;
80 	u32 count;
81 	acpi_status status;
82 
83 	ACPI_FUNCTION_TRACE_PTR(ex_convert_to_integer, obj_desc);
84 
85 	switch (obj_desc->common.type) {
86 	case ACPI_TYPE_INTEGER:
87 
88 		/* No conversion necessary */
89 
90 		*result_desc = obj_desc;
91 		return_ACPI_STATUS(AE_OK);
92 
93 	case ACPI_TYPE_BUFFER:
94 	case ACPI_TYPE_STRING:
95 
96 		/* Note: Takes advantage of common buffer/string fields */
97 
98 		pointer = obj_desc->buffer.pointer;
99 		count = obj_desc->buffer.length;
100 		break;
101 
102 	default:
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 		/*
123 		 * Convert string to an integer - for most cases, the string must be
124 		 * hexadecimal as per the ACPI specification. The only exception (as
125 		 * of ACPI 3.0) is that the to_integer() operator allows both decimal
126 		 * and hexadecimal strings (hex prefixed with "0x").
127 		 */
128 		status = acpi_ut_strtoul64((char *)pointer, flags, &result);
129 		if (ACPI_FAILURE(status)) {
130 			return_ACPI_STATUS(status);
131 		}
132 		break;
133 
134 	case ACPI_TYPE_BUFFER:
135 
136 		/* Check for zero-length buffer */
137 
138 		if (!count) {
139 			return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
140 		}
141 
142 		/* Transfer no more than an integer's worth of data */
143 
144 		if (count > acpi_gbl_integer_byte_width) {
145 			count = acpi_gbl_integer_byte_width;
146 		}
147 
148 		/*
149 		 * Convert buffer to an integer - we simply grab enough raw data
150 		 * from the buffer to fill an integer
151 		 */
152 		for (i = 0; i < count; i++) {
153 			/*
154 			 * Get next byte and shift it into the Result.
155 			 * Little endian is used, meaning that the first byte of the buffer
156 			 * is the LSB of the integer
157 			 */
158 			result |= (((acpi_integer) pointer[i]) << (i * 8));
159 		}
160 		break;
161 
162 	default:
163 
164 		/* No other types can get here */
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 	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 		/*
219 		 * Create a new Buffer object.
220 		 * Need enough space for one integer
221 		 */
222 		return_desc =
223 		    acpi_ut_create_buffer_object(acpi_gbl_integer_byte_width);
224 		if (!return_desc) {
225 			return_ACPI_STATUS(AE_NO_MEMORY);
226 		}
227 
228 		/* Copy the integer to the buffer, LSB first */
229 
230 		new_buf = return_desc->buffer.pointer;
231 		ACPI_MEMCPY(new_buf,
232 			    &obj_desc->integer.value,
233 			    acpi_gbl_integer_byte_width);
234 		break;
235 
236 	case ACPI_TYPE_STRING:
237 
238 		/*
239 		 * Create a new Buffer object
240 		 * Size will be the string length
241 		 *
242 		 * NOTE: Add one to the string length to include the null terminator.
243 		 * The ACPI spec is unclear on this subject, but there is existing
244 		 * ASL/AML code that depends on the null being transferred to the new
245 		 * buffer.
246 		 */
247 		return_desc = acpi_ut_create_buffer_object((acpi_size)
248 							   obj_desc->string.
249 							   length + 1);
250 		if (!return_desc) {
251 			return_ACPI_STATUS(AE_NO_MEMORY);
252 		}
253 
254 		/* Copy the string to the buffer */
255 
256 		new_buf = return_desc->buffer.pointer;
257 		ACPI_STRNCPY((char *)new_buf, (char *)obj_desc->string.pointer,
258 			     obj_desc->string.length);
259 		break;
260 
261 	default:
262 		return_ACPI_STATUS(AE_TYPE);
263 	}
264 
265 	/* Mark buffer initialized */
266 
267 	return_desc->common.flags |= AOPOBJ_DATA_VALID;
268 	*result_desc = return_desc;
269 	return_ACPI_STATUS(AE_OK);
270 }
271 
272 /*******************************************************************************
273  *
274  * FUNCTION:    acpi_ex_convert_to_ascii
275  *
276  * PARAMETERS:  Integer         - Value to be converted
277  *              Base            - ACPI_STRING_DECIMAL or ACPI_STRING_HEX
278  *              String          - Where the string is returned
279  *              data_width      - Size of data item to be converted, in bytes
280  *
281  * RETURN:      Actual string length
282  *
283  * DESCRIPTION: Convert an ACPI Integer to a hex or decimal string
284  *
285  ******************************************************************************/
286 
287 static u32
288 acpi_ex_convert_to_ascii(acpi_integer integer,
289 			 u16 base, u8 * string, u8 data_width)
290 {
291 	acpi_integer digit;
292 	u32 i;
293 	u32 j;
294 	u32 k = 0;
295 	u32 hex_length;
296 	u32 decimal_length;
297 	u32 remainder;
298 	u8 supress_zeros;
299 
300 	ACPI_FUNCTION_ENTRY();
301 
302 	switch (base) {
303 	case 10:
304 
305 		/* Setup max length for the decimal number */
306 
307 		switch (data_width) {
308 		case 1:
309 			decimal_length = ACPI_MAX8_DECIMAL_DIGITS;
310 			break;
311 
312 		case 4:
313 			decimal_length = ACPI_MAX32_DECIMAL_DIGITS;
314 			break;
315 
316 		case 8:
317 		default:
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 = acpi_ut_create_string_object((acpi_size)
522 							   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((acpi_integer)
535 							    obj_desc->buffer.
536 							    pointer[i], base,
537 							    new_buf, 1);
538 			*new_buf++ = separator;	/* each separated by a comma or space */
539 		}
540 
541 		/*
542 		 * Null terminate the string
543 		 * (overwrites final comma/space from above)
544 		 */
545 		if (obj_desc->buffer.length) {
546 			new_buf--;
547 		}
548 		*new_buf = 0;
549 		break;
550 
551 	default:
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 			/* No conversion allowed for these types */
606 
607 			if (destination_type != source_desc->common.type) {
608 				ACPI_DEBUG_PRINT((ACPI_DB_INFO,
609 						  "Explicit operator, will store (%s) over existing type (%s)\n",
610 						  acpi_ut_get_object_type_name
611 						  (source_desc),
612 						  acpi_ut_get_type_name
613 						  (destination_type)));
614 				status = AE_TYPE;
615 			}
616 		}
617 		break;
618 
619 	case ARGI_TARGETREF:
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 						       16);
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 			ACPI_ERROR((AE_INFO,
656 				    "Bad destination type during conversion: %X",
657 				    destination_type));
658 			status = AE_AML_INTERNAL;
659 			break;
660 		}
661 		break;
662 
663 	case ARGI_REFERENCE:
664 		/*
665 		 * create_xxxx_field cases - we are storing the field object into the name
666 		 */
667 		break;
668 
669 	default:
670 		ACPI_ERROR((AE_INFO,
671 			    "Unknown Target type ID 0x%X AmlOpcode %X DestType %s",
672 			    GET_CURRENT_ARG_TYPE(walk_state->op_info->
673 						 runtime_args),
674 			    walk_state->opcode,
675 			    acpi_ut_get_type_name(destination_type)));
676 		status = AE_AML_INTERNAL;
677 	}
678 
679 	/*
680 	 * Source-to-Target conversion semantics:
681 	 *
682 	 * If conversion to the target type cannot be performed, then simply
683 	 * overwrite the target with the new object and type.
684 	 */
685 	if (status == AE_TYPE) {
686 		status = AE_OK;
687 	}
688 
689 	return_ACPI_STATUS(status);
690 }
691