xref: /openbmc/linux/drivers/acpi/acpica/exconvrt.c (revision d3964221)
1 /******************************************************************************
2  *
3  * Module Name: exconvrt - Object conversion routines
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2017, 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(ACPI_CAST_PTR(char, pointer),
128 					   (acpi_gbl_integer_byte_width |
129 					    flags), &result);
130 		if (ACPI_FAILURE(status)) {
131 			return_ACPI_STATUS(status);
132 		}
133 		break;
134 
135 	case ACPI_TYPE_BUFFER:
136 
137 		/* Check for zero-length buffer */
138 
139 		if (!count) {
140 			return_ACPI_STATUS(AE_AML_BUFFER_LIMIT);
141 		}
142 
143 		/* Transfer no more than an integer's worth of data */
144 
145 		if (count > acpi_gbl_integer_byte_width) {
146 			count = acpi_gbl_integer_byte_width;
147 		}
148 
149 		/*
150 		 * Convert buffer to an integer - we simply grab enough raw data
151 		 * from the buffer to fill an integer
152 		 */
153 		for (i = 0; i < count; i++) {
154 			/*
155 			 * Get next byte and shift it into the Result.
156 			 * Little endian is used, meaning that the first byte of the buffer
157 			 * is the LSB of the integer
158 			 */
159 			result |= (((u64) pointer[i]) << (i * 8));
160 		}
161 		break;
162 
163 	default:
164 
165 		/* No other types can get here */
166 
167 		break;
168 	}
169 
170 	/* Create a new integer */
171 
172 	return_desc = acpi_ut_create_integer_object(result);
173 	if (!return_desc) {
174 		return_ACPI_STATUS(AE_NO_MEMORY);
175 	}
176 
177 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Converted value: %8.8X%8.8X\n",
178 			  ACPI_FORMAT_UINT64(result)));
179 
180 	/* Save the Result */
181 
182 	(void)acpi_ex_truncate_for32bit_table(return_desc);
183 	*result_desc = return_desc;
184 	return_ACPI_STATUS(AE_OK);
185 }
186 
187 /*******************************************************************************
188  *
189  * FUNCTION:    acpi_ex_convert_to_buffer
190  *
191  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
192  *                                Integer, Buffer, or String
193  *              result_desc     - Where the new buffer object is returned
194  *
195  * RETURN:      Status
196  *
197  * DESCRIPTION: Convert an ACPI Object to a Buffer
198  *
199  ******************************************************************************/
200 
201 acpi_status
202 acpi_ex_convert_to_buffer(union acpi_operand_object *obj_desc,
203 			  union acpi_operand_object **result_desc)
204 {
205 	union acpi_operand_object *return_desc;
206 	u8 *new_buf;
207 
208 	ACPI_FUNCTION_TRACE_PTR(ex_convert_to_buffer, obj_desc);
209 
210 	switch (obj_desc->common.type) {
211 	case ACPI_TYPE_BUFFER:
212 
213 		/* No conversion necessary */
214 
215 		*result_desc = obj_desc;
216 		return_ACPI_STATUS(AE_OK);
217 
218 	case ACPI_TYPE_INTEGER:
219 		/*
220 		 * Create a new Buffer object.
221 		 * Need enough space for one integer
222 		 */
223 		return_desc =
224 		    acpi_ut_create_buffer_object(acpi_gbl_integer_byte_width);
225 		if (!return_desc) {
226 			return_ACPI_STATUS(AE_NO_MEMORY);
227 		}
228 
229 		/* Copy the integer to the buffer, LSB first */
230 
231 		new_buf = return_desc->buffer.pointer;
232 		memcpy(new_buf, &obj_desc->integer.value,
233 		       acpi_gbl_integer_byte_width);
234 		break;
235 
236 	case ACPI_TYPE_STRING:
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 		strncpy((char *)new_buf, (char *)obj_desc->string.pointer,
257 			obj_desc->string.length);
258 		break;
259 
260 	default:
261 
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(u64 integer, u16 base, u8 *string, u8 data_width)
289 {
290 	u64 digit;
291 	u32 i;
292 	u32 j;
293 	u32 k = 0;
294 	u32 hex_length;
295 	u32 decimal_length;
296 	u32 remainder;
297 	u8 supress_zeros;
298 
299 	ACPI_FUNCTION_ENTRY();
300 
301 	switch (base) {
302 	case 10:
303 
304 		/* Setup max length for the decimal number */
305 
306 		switch (data_width) {
307 		case 1:
308 
309 			decimal_length = ACPI_MAX8_DECIMAL_DIGITS;
310 			break;
311 
312 		case 4:
313 
314 			decimal_length = ACPI_MAX32_DECIMAL_DIGITS;
315 			break;
316 
317 		case 8:
318 		default:
319 
320 			decimal_length = ACPI_MAX64_DECIMAL_DIGITS;
321 			break;
322 		}
323 
324 		supress_zeros = TRUE;	/* No leading zeros */
325 		remainder = 0;
326 
327 		for (i = decimal_length; i > 0; i--) {
328 
329 			/* Divide by nth factor of 10 */
330 
331 			digit = integer;
332 			for (j = 0; j < i; j++) {
333 				(void)acpi_ut_short_divide(digit, 10, &digit,
334 							   &remainder);
335 			}
336 
337 			/* Handle leading zeros */
338 
339 			if (remainder != 0) {
340 				supress_zeros = FALSE;
341 			}
342 
343 			if (!supress_zeros) {
344 				string[k] = (u8) (ACPI_ASCII_ZERO + remainder);
345 				k++;
346 			}
347 		}
348 		break;
349 
350 	case 16:
351 
352 		/* hex_length: 2 ascii hex chars per data byte */
353 
354 		hex_length = ACPI_MUL_2(data_width);
355 		for (i = 0, j = (hex_length - 1); i < hex_length; i++, j--) {
356 
357 			/* Get one hex digit, most significant digits first */
358 
359 			string[k] = (u8)
360 			    acpi_ut_hex_to_ascii_char(integer, ACPI_MUL_4(j));
361 			k++;
362 		}
363 		break;
364 
365 	default:
366 		return (0);
367 	}
368 
369 	/*
370 	 * Since leading zeros are suppressed, we must check for the case where
371 	 * the integer equals 0
372 	 *
373 	 * Finally, null terminate the string and return the length
374 	 */
375 	if (!k) {
376 		string[0] = ACPI_ASCII_ZERO;
377 		k = 1;
378 	}
379 
380 	string[k] = 0;
381 	return ((u32) k);
382 }
383 
384 /*******************************************************************************
385  *
386  * FUNCTION:    acpi_ex_convert_to_string
387  *
388  * PARAMETERS:  obj_desc        - Object to be converted. Must be an
389  *                                Integer, Buffer, or String
390  *              result_desc     - Where the string object is returned
391  *              type            - String flags (base and conversion type)
392  *
393  * RETURN:      Status
394  *
395  * DESCRIPTION: Convert an ACPI Object to a string
396  *
397  ******************************************************************************/
398 
399 acpi_status
400 acpi_ex_convert_to_string(union acpi_operand_object * obj_desc,
401 			  union acpi_operand_object ** result_desc, u32 type)
402 {
403 	union acpi_operand_object *return_desc;
404 	u8 *new_buf;
405 	u32 i;
406 	u32 string_length = 0;
407 	u16 base = 16;
408 	u8 separator = ',';
409 
410 	ACPI_FUNCTION_TRACE_PTR(ex_convert_to_string, obj_desc);
411 
412 	switch (obj_desc->common.type) {
413 	case ACPI_TYPE_STRING:
414 
415 		/* No conversion necessary */
416 
417 		*result_desc = obj_desc;
418 		return_ACPI_STATUS(AE_OK);
419 
420 	case ACPI_TYPE_INTEGER:
421 
422 		switch (type) {
423 		case ACPI_EXPLICIT_CONVERT_DECIMAL:
424 
425 			/* Make room for maximum decimal number */
426 
427 			string_length = ACPI_MAX_DECIMAL_DIGITS;
428 			base = 10;
429 			break;
430 
431 		default:
432 
433 			/* Two hex string characters for each integer byte */
434 
435 			string_length = ACPI_MUL_2(acpi_gbl_integer_byte_width);
436 			break;
437 		}
438 
439 		/*
440 		 * Create a new String
441 		 * Need enough space for one ASCII integer (plus null terminator)
442 		 */
443 		return_desc =
444 		    acpi_ut_create_string_object((acpi_size)string_length);
445 		if (!return_desc) {
446 			return_ACPI_STATUS(AE_NO_MEMORY);
447 		}
448 
449 		new_buf = return_desc->buffer.pointer;
450 
451 		/* Convert integer to string */
452 
453 		string_length =
454 		    acpi_ex_convert_to_ascii(obj_desc->integer.value, base,
455 					     new_buf,
456 					     acpi_gbl_integer_byte_width);
457 
458 		/* Null terminate at the correct place */
459 
460 		return_desc->string.length = string_length;
461 		new_buf[string_length] = 0;
462 		break;
463 
464 	case ACPI_TYPE_BUFFER:
465 
466 		/* Setup string length, base, and separator */
467 
468 		switch (type) {
469 		case ACPI_EXPLICIT_CONVERT_DECIMAL:	/* Used by to_decimal_string */
470 			/*
471 			 * From ACPI: "If Data is a buffer, it is converted to a string of
472 			 * decimal values separated by commas."
473 			 */
474 			base = 10;
475 
476 			/*
477 			 * Calculate the final string length. Individual string values
478 			 * are variable length (include separator for each)
479 			 */
480 			for (i = 0; i < obj_desc->buffer.length; i++) {
481 				if (obj_desc->buffer.pointer[i] >= 100) {
482 					string_length += 4;
483 				} else if (obj_desc->buffer.pointer[i] >= 10) {
484 					string_length += 3;
485 				} else {
486 					string_length += 2;
487 				}
488 			}
489 			break;
490 
491 		case ACPI_IMPLICIT_CONVERT_HEX:
492 			/*
493 			 * From the ACPI spec:
494 			 *"The entire contents of the buffer are converted to a string of
495 			 * two-character hexadecimal numbers, each separated by a space."
496 			 */
497 			separator = ' ';
498 			string_length = (obj_desc->buffer.length * 3);
499 			break;
500 
501 		case ACPI_EXPLICIT_CONVERT_HEX:	/* Used by to_hex_string */
502 			/*
503 			 * From ACPI: "If Data is a buffer, it is converted to a string of
504 			 * hexadecimal values separated by commas."
505 			 */
506 			string_length = (obj_desc->buffer.length * 3);
507 			break;
508 
509 		default:
510 			return_ACPI_STATUS(AE_BAD_PARAMETER);
511 		}
512 
513 		/*
514 		 * Create a new string object and string buffer
515 		 * (-1 because of extra separator included in string_length from above)
516 		 * Allow creation of zero-length strings from zero-length buffers.
517 		 */
518 		if (string_length) {
519 			string_length--;
520 		}
521 
522 		return_desc =
523 		    acpi_ut_create_string_object((acpi_size)string_length);
524 		if (!return_desc) {
525 			return_ACPI_STATUS(AE_NO_MEMORY);
526 		}
527 
528 		new_buf = return_desc->buffer.pointer;
529 
530 		/*
531 		 * Convert buffer bytes to hex or decimal values
532 		 * (separated by commas or spaces)
533 		 */
534 		for (i = 0; i < obj_desc->buffer.length; i++) {
535 			new_buf += acpi_ex_convert_to_ascii((u64) obj_desc->
536 							    buffer.pointer[i],
537 							    base, 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 
553 		return_ACPI_STATUS(AE_TYPE);
554 	}
555 
556 	*result_desc = return_desc;
557 	return_ACPI_STATUS(AE_OK);
558 }
559 
560 /*******************************************************************************
561  *
562  * FUNCTION:    acpi_ex_convert_to_target_type
563  *
564  * PARAMETERS:  destination_type    - Current type of the destination
565  *              source_desc         - Source object to be converted.
566  *              result_desc         - Where the converted object is returned
567  *              walk_state          - Current method state
568  *
569  * RETURN:      Status
570  *
571  * DESCRIPTION: Implements "implicit conversion" rules for storing an object.
572  *
573  ******************************************************************************/
574 
575 acpi_status
576 acpi_ex_convert_to_target_type(acpi_object_type destination_type,
577 			       union acpi_operand_object *source_desc,
578 			       union acpi_operand_object **result_desc,
579 			       struct acpi_walk_state *walk_state)
580 {
581 	acpi_status status = AE_OK;
582 
583 	ACPI_FUNCTION_TRACE(ex_convert_to_target_type);
584 
585 	/* Default behavior */
586 
587 	*result_desc = source_desc;
588 
589 	/*
590 	 * If required by the target,
591 	 * perform implicit conversion on the source before we store it.
592 	 */
593 	switch (GET_CURRENT_ARG_TYPE(walk_state->op_info->runtime_args)) {
594 	case ARGI_SIMPLE_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 	case ARGI_STORE_TARGET:
622 
623 		switch (destination_type) {
624 		case ACPI_TYPE_INTEGER:
625 		case ACPI_TYPE_BUFFER_FIELD:
626 		case ACPI_TYPE_LOCAL_BANK_FIELD:
627 		case ACPI_TYPE_LOCAL_INDEX_FIELD:
628 			/*
629 			 * These types require an Integer operand. We can convert
630 			 * a Buffer or a String to an Integer if necessary.
631 			 */
632 			status =
633 			    acpi_ex_convert_to_integer(source_desc, result_desc,
634 						       ACPI_STRTOUL_BASE16);
635 			break;
636 
637 		case ACPI_TYPE_STRING:
638 			/*
639 			 * The operand must be a String. We can convert an
640 			 * Integer or Buffer if necessary
641 			 */
642 			status =
643 			    acpi_ex_convert_to_string(source_desc, result_desc,
644 						      ACPI_IMPLICIT_CONVERT_HEX);
645 			break;
646 
647 		case ACPI_TYPE_BUFFER:
648 			/*
649 			 * The operand must be a Buffer. We can convert an
650 			 * Integer or String if necessary
651 			 */
652 			status =
653 			    acpi_ex_convert_to_buffer(source_desc, result_desc);
654 			break;
655 
656 		default:
657 
658 			ACPI_ERROR((AE_INFO,
659 				    "Bad destination type during conversion: 0x%X",
660 				    destination_type));
661 			status = AE_AML_INTERNAL;
662 			break;
663 		}
664 		break;
665 
666 	case ARGI_REFERENCE:
667 		/*
668 		 * create_xxxx_field cases - we are storing the field object into the name
669 		 */
670 		break;
671 
672 	default:
673 
674 		ACPI_ERROR((AE_INFO,
675 			    "Unknown Target type ID 0x%X AmlOpcode 0x%X DestType %s",
676 			    GET_CURRENT_ARG_TYPE(walk_state->op_info->
677 						 runtime_args),
678 			    walk_state->opcode,
679 			    acpi_ut_get_type_name(destination_type)));
680 		status = AE_AML_INTERNAL;
681 	}
682 
683 	/*
684 	 * Source-to-Target conversion semantics:
685 	 *
686 	 * If conversion to the target type cannot be performed, then simply
687 	 * overwrite the target with the new object and type.
688 	 */
689 	if (status == AE_TYPE) {
690 		status = AE_OK;
691 	}
692 
693 	return_ACPI_STATUS(status);
694 }
695