xref: /linux/drivers/acpi/acpica/nsrepair.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /******************************************************************************
2  *
3  * Module Name: nsrepair - Repair for objects returned by predefined methods
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 "acnamesp.h"
47 #include "acinterp.h"
48 #include "acpredef.h"
49 #include "amlresrc.h"
50 
51 #define _COMPONENT          ACPI_NAMESPACE
52 ACPI_MODULE_NAME("nsrepair")
53 
54 /*******************************************************************************
55  *
56  * This module attempts to repair or convert objects returned by the
57  * predefined methods to an object type that is expected, as per the ACPI
58  * specification. The need for this code is dictated by the many machines that
59  * return incorrect types for the standard predefined methods. Performing these
60  * conversions here, in one place, eliminates the need for individual ACPI
61  * device drivers to do the same. Note: Most of these conversions are different
62  * than the internal object conversion routines used for implicit object
63  * conversion.
64  *
65  * The following conversions can be performed as necessary:
66  *
67  * Integer -> String
68  * Integer -> Buffer
69  * String  -> Integer
70  * String  -> Buffer
71  * Buffer  -> Integer
72  * Buffer  -> String
73  * Buffer  -> Package of Integers
74  * Package -> Package of one Package
75  *
76  * Additional conversions that are available:
77  *  Convert a null return or zero return value to an end_tag descriptor
78  *  Convert an ASCII string to a Unicode buffer
79  *
80  * An incorrect standalone object is wrapped with required outer package
81  *
82  * Additional possible repairs:
83  * Required package elements that are NULL replaced by Integer/String/Buffer
84  *
85  ******************************************************************************/
86 /* Local prototypes */
87 static const struct acpi_simple_repair_info *acpi_ns_match_simple_repair(struct
88 									 acpi_namespace_node
89 									 *node,
90 									 u32
91 									 return_btype,
92 									 u32
93 									 package_index);
94 
95 /*
96  * Special but simple repairs for some names.
97  *
98  * 2nd argument: Unexpected types that can be repaired
99  */
100 static const struct acpi_simple_repair_info acpi_object_repair_info[] = {
101 	/* Resource descriptor conversions */
102 
103 	{"_CRS",
104 	 ACPI_RTYPE_INTEGER | ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER |
105 	 ACPI_RTYPE_NONE,
106 	 ACPI_NOT_PACKAGE_ELEMENT,
107 	 acpi_ns_convert_to_resource},
108 	{"_DMA",
109 	 ACPI_RTYPE_INTEGER | ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER |
110 	 ACPI_RTYPE_NONE,
111 	 ACPI_NOT_PACKAGE_ELEMENT,
112 	 acpi_ns_convert_to_resource},
113 	{"_PRS",
114 	 ACPI_RTYPE_INTEGER | ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER |
115 	 ACPI_RTYPE_NONE,
116 	 ACPI_NOT_PACKAGE_ELEMENT,
117 	 acpi_ns_convert_to_resource},
118 
119 	/* Unicode conversions */
120 
121 	{"_MLS", ACPI_RTYPE_STRING, 1,
122 	 acpi_ns_convert_to_unicode},
123 	{"_STR", ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER,
124 	 ACPI_NOT_PACKAGE_ELEMENT,
125 	 acpi_ns_convert_to_unicode},
126 	{{0, 0, 0, 0}, 0, 0, NULL}	/* Table terminator */
127 };
128 
129 /*******************************************************************************
130  *
131  * FUNCTION:    acpi_ns_simple_repair
132  *
133  * PARAMETERS:  info                - Method execution information block
134  *              expected_btypes     - Object types expected
135  *              package_index       - Index of object within parent package (if
136  *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
137  *                                    otherwise)
138  *              return_object_ptr   - Pointer to the object returned from the
139  *                                    evaluation of a method or object
140  *
141  * RETURN:      Status. AE_OK if repair was successful.
142  *
143  * DESCRIPTION: Attempt to repair/convert a return object of a type that was
144  *              not expected.
145  *
146  ******************************************************************************/
147 
148 acpi_status
149 acpi_ns_simple_repair(struct acpi_evaluate_info *info,
150 		      u32 expected_btypes,
151 		      u32 package_index,
152 		      union acpi_operand_object **return_object_ptr)
153 {
154 	union acpi_operand_object *return_object = *return_object_ptr;
155 	union acpi_operand_object *new_object = NULL;
156 	acpi_status status;
157 	const struct acpi_simple_repair_info *predefined;
158 
159 	ACPI_FUNCTION_NAME(ns_simple_repair);
160 
161 	/*
162 	 * Special repairs for certain names that are in the repair table.
163 	 * Check if this name is in the list of repairable names.
164 	 */
165 	predefined = acpi_ns_match_simple_repair(info->node,
166 						 info->return_btype,
167 						 package_index);
168 	if (predefined) {
169 		if (!return_object) {
170 			ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
171 					      ACPI_WARN_ALWAYS,
172 					      "Missing expected return value"));
173 		}
174 
175 		status =
176 		    predefined->object_converter(return_object, &new_object);
177 		if (ACPI_FAILURE(status)) {
178 
179 			/* A fatal error occurred during a conversion */
180 
181 			ACPI_EXCEPTION((AE_INFO, status,
182 					"During return object analysis"));
183 			return (status);
184 		}
185 		if (new_object) {
186 			goto object_repaired;
187 		}
188 	}
189 
190 	/*
191 	 * Do not perform simple object repair unless the return type is not
192 	 * expected.
193 	 */
194 	if (info->return_btype & expected_btypes) {
195 		return (AE_OK);
196 	}
197 
198 	/*
199 	 * At this point, we know that the type of the returned object was not
200 	 * one of the expected types for this predefined name. Attempt to
201 	 * repair the object by converting it to one of the expected object
202 	 * types for this predefined name.
203 	 */
204 
205 	/*
206 	 * If there is no return value, check if we require a return value for
207 	 * this predefined name. Either one return value is expected, or none,
208 	 * for both methods and other objects.
209 	 *
210 	 * Try to fix if there was no return object. Warning if failed to fix.
211 	 */
212 	if (!return_object) {
213 		if (expected_btypes && (!(expected_btypes & ACPI_RTYPE_NONE))) {
214 			if (package_index != ACPI_NOT_PACKAGE_ELEMENT) {
215 				ACPI_WARN_PREDEFINED((AE_INFO,
216 						      info->full_pathname,
217 						      ACPI_WARN_ALWAYS,
218 						      "Found unexpected NULL package element"));
219 
220 				status =
221 				    acpi_ns_repair_null_element(info,
222 								expected_btypes,
223 								package_index,
224 								return_object_ptr);
225 				if (ACPI_SUCCESS(status)) {
226 					return (AE_OK);	/* Repair was successful */
227 				}
228 			} else {
229 				ACPI_WARN_PREDEFINED((AE_INFO,
230 						      info->full_pathname,
231 						      ACPI_WARN_ALWAYS,
232 						      "Missing expected return value"));
233 			}
234 
235 			return (AE_AML_NO_RETURN_VALUE);
236 		}
237 	}
238 
239 	if (expected_btypes & ACPI_RTYPE_INTEGER) {
240 		status = acpi_ns_convert_to_integer(return_object, &new_object);
241 		if (ACPI_SUCCESS(status)) {
242 			goto object_repaired;
243 		}
244 	}
245 	if (expected_btypes & ACPI_RTYPE_STRING) {
246 		status = acpi_ns_convert_to_string(return_object, &new_object);
247 		if (ACPI_SUCCESS(status)) {
248 			goto object_repaired;
249 		}
250 	}
251 	if (expected_btypes & ACPI_RTYPE_BUFFER) {
252 		status = acpi_ns_convert_to_buffer(return_object, &new_object);
253 		if (ACPI_SUCCESS(status)) {
254 			goto object_repaired;
255 		}
256 	}
257 	if (expected_btypes & ACPI_RTYPE_PACKAGE) {
258 		/*
259 		 * A package is expected. We will wrap the existing object with a
260 		 * new package object. It is often the case that if a variable-length
261 		 * package is required, but there is only a single object needed, the
262 		 * BIOS will return that object instead of wrapping it with a Package
263 		 * object. Note: after the wrapping, the package will be validated
264 		 * for correct contents (expected object type or types).
265 		 */
266 		status =
267 		    acpi_ns_wrap_with_package(info, return_object, &new_object);
268 		if (ACPI_SUCCESS(status)) {
269 			/*
270 			 * The original object just had its reference count
271 			 * incremented for being inserted into the new package.
272 			 */
273 			*return_object_ptr = new_object;	/* New Package object */
274 			info->return_flags |= ACPI_OBJECT_REPAIRED;
275 			return (AE_OK);
276 		}
277 	}
278 
279 	/* We cannot repair this object */
280 
281 	return (AE_AML_OPERAND_TYPE);
282 
283 object_repaired:
284 
285 	/* Object was successfully repaired */
286 
287 	if (package_index != ACPI_NOT_PACKAGE_ELEMENT) {
288 		/*
289 		 * The original object is a package element. We need to
290 		 * decrement the reference count of the original object,
291 		 * for removing it from the package.
292 		 *
293 		 * However, if the original object was just wrapped with a
294 		 * package object as part of the repair, we don't need to
295 		 * change the reference count.
296 		 */
297 		if (!(info->return_flags & ACPI_OBJECT_WRAPPED)) {
298 			new_object->common.reference_count =
299 			    return_object->common.reference_count;
300 
301 			if (return_object->common.reference_count > 1) {
302 				return_object->common.reference_count--;
303 			}
304 		}
305 
306 		ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
307 				  "%s: Converted %s to expected %s at Package index %u\n",
308 				  info->full_pathname,
309 				  acpi_ut_get_object_type_name(return_object),
310 				  acpi_ut_get_object_type_name(new_object),
311 				  package_index));
312 	} else {
313 		ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
314 				  "%s: Converted %s to expected %s\n",
315 				  info->full_pathname,
316 				  acpi_ut_get_object_type_name(return_object),
317 				  acpi_ut_get_object_type_name(new_object)));
318 	}
319 
320 	/* Delete old object, install the new return object */
321 
322 	acpi_ut_remove_reference(return_object);
323 	*return_object_ptr = new_object;
324 	info->return_flags |= ACPI_OBJECT_REPAIRED;
325 	return (AE_OK);
326 }
327 
328 /******************************************************************************
329  *
330  * FUNCTION:    acpi_ns_match_simple_repair
331  *
332  * PARAMETERS:  node                - Namespace node for the method/object
333  *              return_btype        - Object type that was returned
334  *              package_index       - Index of object within parent package (if
335  *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
336  *                                    otherwise)
337  *
338  * RETURN:      Pointer to entry in repair table. NULL indicates not found.
339  *
340  * DESCRIPTION: Check an object name against the repairable object list.
341  *
342  *****************************************************************************/
343 
344 static const struct acpi_simple_repair_info *acpi_ns_match_simple_repair(struct
345 									 acpi_namespace_node
346 									 *node,
347 									 u32
348 									 return_btype,
349 									 u32
350 									 package_index)
351 {
352 	const struct acpi_simple_repair_info *this_name;
353 
354 	/* Search info table for a repairable predefined method/object name */
355 
356 	this_name = acpi_object_repair_info;
357 	while (this_name->object_converter) {
358 		if (ACPI_COMPARE_NAME(node->name.ascii, this_name->name)) {
359 
360 			/* Check if we can actually repair this name/type combination */
361 
362 			if ((return_btype & this_name->unexpected_btypes) &&
363 			    (package_index == this_name->package_index)) {
364 				return (this_name);
365 			}
366 
367 			return (NULL);
368 		}
369 		this_name++;
370 	}
371 
372 	return (NULL);		/* Name was not found in the repair table */
373 }
374 
375 /*******************************************************************************
376  *
377  * FUNCTION:    acpi_ns_repair_null_element
378  *
379  * PARAMETERS:  info                - Method execution information block
380  *              expected_btypes     - Object types expected
381  *              package_index       - Index of object within parent package (if
382  *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
383  *                                    otherwise)
384  *              return_object_ptr   - Pointer to the object returned from the
385  *                                    evaluation of a method or object
386  *
387  * RETURN:      Status. AE_OK if repair was successful.
388  *
389  * DESCRIPTION: Attempt to repair a NULL element of a returned Package object.
390  *
391  ******************************************************************************/
392 
393 acpi_status
394 acpi_ns_repair_null_element(struct acpi_evaluate_info * info,
395 			    u32 expected_btypes,
396 			    u32 package_index,
397 			    union acpi_operand_object **return_object_ptr)
398 {
399 	union acpi_operand_object *return_object = *return_object_ptr;
400 	union acpi_operand_object *new_object;
401 
402 	ACPI_FUNCTION_NAME(ns_repair_null_element);
403 
404 	/* No repair needed if return object is non-NULL */
405 
406 	if (return_object) {
407 		return (AE_OK);
408 	}
409 
410 	/*
411 	 * Attempt to repair a NULL element of a Package object. This applies to
412 	 * predefined names that return a fixed-length package and each element
413 	 * is required. It does not apply to variable-length packages where NULL
414 	 * elements are allowed, especially at the end of the package.
415 	 */
416 	if (expected_btypes & ACPI_RTYPE_INTEGER) {
417 
418 		/* Need an integer - create a zero-value integer */
419 
420 		new_object = acpi_ut_create_integer_object((u64)0);
421 	} else if (expected_btypes & ACPI_RTYPE_STRING) {
422 
423 		/* Need a string - create a NULL string */
424 
425 		new_object = acpi_ut_create_string_object(0);
426 	} else if (expected_btypes & ACPI_RTYPE_BUFFER) {
427 
428 		/* Need a buffer - create a zero-length buffer */
429 
430 		new_object = acpi_ut_create_buffer_object(0);
431 	} else {
432 		/* Error for all other expected types */
433 
434 		return (AE_AML_OPERAND_TYPE);
435 	}
436 
437 	if (!new_object) {
438 		return (AE_NO_MEMORY);
439 	}
440 
441 	/* Set the reference count according to the parent Package object */
442 
443 	new_object->common.reference_count =
444 	    info->parent_package->common.reference_count;
445 
446 	ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
447 			  "%s: Converted NULL package element to expected %s at index %u\n",
448 			  info->full_pathname,
449 			  acpi_ut_get_object_type_name(new_object),
450 			  package_index));
451 
452 	*return_object_ptr = new_object;
453 	info->return_flags |= ACPI_OBJECT_REPAIRED;
454 	return (AE_OK);
455 }
456 
457 /******************************************************************************
458  *
459  * FUNCTION:    acpi_ns_remove_null_elements
460  *
461  * PARAMETERS:  info                - Method execution information block
462  *              package_type        - An acpi_return_package_types value
463  *              obj_desc            - A Package object
464  *
465  * RETURN:      None.
466  *
467  * DESCRIPTION: Remove all NULL package elements from packages that contain
468  *              a variable number of subpackages. For these types of
469  *              packages, NULL elements can be safely removed.
470  *
471  *****************************************************************************/
472 
473 void
474 acpi_ns_remove_null_elements(struct acpi_evaluate_info *info,
475 			     u8 package_type,
476 			     union acpi_operand_object *obj_desc)
477 {
478 	union acpi_operand_object **source;
479 	union acpi_operand_object **dest;
480 	u32 count;
481 	u32 new_count;
482 	u32 i;
483 
484 	ACPI_FUNCTION_NAME(ns_remove_null_elements);
485 
486 	/*
487 	 * We can safely remove all NULL elements from these package types:
488 	 * PTYPE1_VAR packages contain a variable number of simple data types.
489 	 * PTYPE2 packages contain a variable number of subpackages.
490 	 */
491 	switch (package_type) {
492 	case ACPI_PTYPE1_VAR:
493 	case ACPI_PTYPE2:
494 	case ACPI_PTYPE2_COUNT:
495 	case ACPI_PTYPE2_PKG_COUNT:
496 	case ACPI_PTYPE2_FIXED:
497 	case ACPI_PTYPE2_MIN:
498 	case ACPI_PTYPE2_REV_FIXED:
499 	case ACPI_PTYPE2_FIX_VAR:
500 		break;
501 
502 	default:
503 	case ACPI_PTYPE2_VAR_VAR:
504 	case ACPI_PTYPE1_FIXED:
505 	case ACPI_PTYPE1_OPTION:
506 		return;
507 	}
508 
509 	count = obj_desc->package.count;
510 	new_count = count;
511 
512 	source = obj_desc->package.elements;
513 	dest = source;
514 
515 	/* Examine all elements of the package object, remove nulls */
516 
517 	for (i = 0; i < count; i++) {
518 		if (!*source) {
519 			new_count--;
520 		} else {
521 			*dest = *source;
522 			dest++;
523 		}
524 		source++;
525 	}
526 
527 	/* Update parent package if any null elements were removed */
528 
529 	if (new_count < count) {
530 		ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
531 				  "%s: Found and removed %u NULL elements\n",
532 				  info->full_pathname, (count - new_count)));
533 
534 		/* NULL terminate list and update the package count */
535 
536 		*dest = NULL;
537 		obj_desc->package.count = new_count;
538 	}
539 }
540 
541 /*******************************************************************************
542  *
543  * FUNCTION:    acpi_ns_wrap_with_package
544  *
545  * PARAMETERS:  info                - Method execution information block
546  *              original_object     - Pointer to the object to repair.
547  *              obj_desc_ptr        - The new package object is returned here
548  *
549  * RETURN:      Status, new object in *obj_desc_ptr
550  *
551  * DESCRIPTION: Repair a common problem with objects that are defined to
552  *              return a variable-length Package of sub-objects. If there is
553  *              only one sub-object, some BIOS code mistakenly simply declares
554  *              the single object instead of a Package with one sub-object.
555  *              This function attempts to repair this error by wrapping a
556  *              Package object around the original object, creating the
557  *              correct and expected Package with one sub-object.
558  *
559  *              Names that can be repaired in this manner include:
560  *              _ALR, _CSD, _HPX, _MLS, _PLD, _PRT, _PSS, _TRT, _TSS,
561  *              _BCL, _DOD, _FIX, _Sx
562  *
563  ******************************************************************************/
564 
565 acpi_status
566 acpi_ns_wrap_with_package(struct acpi_evaluate_info *info,
567 			  union acpi_operand_object *original_object,
568 			  union acpi_operand_object **obj_desc_ptr)
569 {
570 	union acpi_operand_object *pkg_obj_desc;
571 
572 	ACPI_FUNCTION_NAME(ns_wrap_with_package);
573 
574 	/*
575 	 * Create the new outer package and populate it. The new package will
576 	 * have a single element, the lone sub-object.
577 	 */
578 	pkg_obj_desc = acpi_ut_create_package_object(1);
579 	if (!pkg_obj_desc) {
580 		return (AE_NO_MEMORY);
581 	}
582 
583 	pkg_obj_desc->package.elements[0] = original_object;
584 
585 	ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
586 			  "%s: Wrapped %s with expected Package object\n",
587 			  info->full_pathname,
588 			  acpi_ut_get_object_type_name(original_object)));
589 
590 	/* Return the new object in the object pointer */
591 
592 	*obj_desc_ptr = pkg_obj_desc;
593 	info->return_flags |= ACPI_OBJECT_REPAIRED | ACPI_OBJECT_WRAPPED;
594 	return (AE_OK);
595 }
596