xref: /openbmc/linux/drivers/acpi/acpica/nsrepair.c (revision 86e281fc)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: nsrepair - Repair for objects returned by predefined methods
5  *
6  * Copyright (C) 2000 - 2023, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acnamesp.h"
13 #include "acinterp.h"
14 #include "acpredef.h"
15 #include "amlresrc.h"
16 
17 #define _COMPONENT          ACPI_NAMESPACE
18 ACPI_MODULE_NAME("nsrepair")
19 
20 /*******************************************************************************
21  *
22  * This module attempts to repair or convert objects returned by the
23  * predefined methods to an object type that is expected, as per the ACPI
24  * specification. The need for this code is dictated by the many machines that
25  * return incorrect types for the standard predefined methods. Performing these
26  * conversions here, in one place, eliminates the need for individual ACPI
27  * device drivers to do the same. Note: Most of these conversions are different
28  * than the internal object conversion routines used for implicit object
29  * conversion.
30  *
31  * The following conversions can be performed as necessary:
32  *
33  * Integer -> String
34  * Integer -> Buffer
35  * String  -> Integer
36  * String  -> Buffer
37  * Buffer  -> Integer
38  * Buffer  -> String
39  * Buffer  -> Package of Integers
40  * Package -> Package of one Package
41  *
42  * Additional conversions that are available:
43  *  Convert a null return or zero return value to an end_tag descriptor
44  *  Convert an ASCII string to a Unicode buffer
45  *
46  * An incorrect standalone object is wrapped with required outer package
47  *
48  * Additional possible repairs:
49  * Required package elements that are NULL replaced by Integer/String/Buffer
50  *
51  ******************************************************************************/
52 /* Local prototypes */
53 static const struct acpi_simple_repair_info *acpi_ns_match_simple_repair(struct
54 									 acpi_namespace_node
55 									 *node,
56 									 u32
57 									 return_btype,
58 									 u32
59 									 package_index);
60 
61 /*
62  * Special but simple repairs for some names.
63  *
64  * 2nd argument: Unexpected types that can be repaired
65  */
66 static const struct acpi_simple_repair_info acpi_object_repair_info[] = {
67 	/* Resource descriptor conversions */
68 
69 	{"_CRS",
70 	 ACPI_RTYPE_INTEGER | ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER |
71 	 ACPI_RTYPE_NONE,
72 	 ACPI_NOT_PACKAGE_ELEMENT,
73 	 acpi_ns_convert_to_resource},
74 	{"_DMA",
75 	 ACPI_RTYPE_INTEGER | ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER |
76 	 ACPI_RTYPE_NONE,
77 	 ACPI_NOT_PACKAGE_ELEMENT,
78 	 acpi_ns_convert_to_resource},
79 	{"_PRS",
80 	 ACPI_RTYPE_INTEGER | ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER |
81 	 ACPI_RTYPE_NONE,
82 	 ACPI_NOT_PACKAGE_ELEMENT,
83 	 acpi_ns_convert_to_resource},
84 
85 	/* Object reference conversions */
86 
87 	{"_DEP", ACPI_RTYPE_STRING, ACPI_ALL_PACKAGE_ELEMENTS,
88 	 acpi_ns_convert_to_reference},
89 
90 	/* Unicode conversions */
91 
92 	{"_MLS", ACPI_RTYPE_STRING, 1,
93 	 acpi_ns_convert_to_unicode},
94 	{"_STR", ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER,
95 	 ACPI_NOT_PACKAGE_ELEMENT,
96 	 acpi_ns_convert_to_unicode},
97 	{{0, 0, 0, 0}, 0, 0, NULL}	/* Table terminator */
98 };
99 
100 /*******************************************************************************
101  *
102  * FUNCTION:    acpi_ns_simple_repair
103  *
104  * PARAMETERS:  info                - Method execution information block
105  *              expected_btypes     - Object types expected
106  *              package_index       - Index of object within parent package (if
107  *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
108  *                                    otherwise)
109  *              return_object_ptr   - Pointer to the object returned from the
110  *                                    evaluation of a method or object
111  *
112  * RETURN:      Status. AE_OK if repair was successful.
113  *
114  * DESCRIPTION: Attempt to repair/convert a return object of a type that was
115  *              not expected.
116  *
117  ******************************************************************************/
118 
119 acpi_status
120 acpi_ns_simple_repair(struct acpi_evaluate_info *info,
121 		      u32 expected_btypes,
122 		      u32 package_index,
123 		      union acpi_operand_object **return_object_ptr)
124 {
125 	union acpi_operand_object *return_object = *return_object_ptr;
126 	union acpi_operand_object *new_object = NULL;
127 	acpi_status status;
128 	const struct acpi_simple_repair_info *predefined;
129 
130 	ACPI_FUNCTION_NAME(ns_simple_repair);
131 
132 	/*
133 	 * Special repairs for certain names that are in the repair table.
134 	 * Check if this name is in the list of repairable names.
135 	 */
136 	predefined = acpi_ns_match_simple_repair(info->node,
137 						 info->return_btype,
138 						 package_index);
139 	if (predefined) {
140 		if (!return_object) {
141 			ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
142 					      ACPI_WARN_ALWAYS,
143 					      "Missing expected return value"));
144 		}
145 
146 		status = predefined->object_converter(info->node, return_object,
147 						      &new_object);
148 		if (ACPI_FAILURE(status)) {
149 
150 			/* A fatal error occurred during a conversion */
151 
152 			ACPI_EXCEPTION((AE_INFO, status,
153 					"During return object analysis"));
154 			return (status);
155 		}
156 		if (new_object) {
157 			goto object_repaired;
158 		}
159 	}
160 
161 	/*
162 	 * Do not perform simple object repair unless the return type is not
163 	 * expected.
164 	 */
165 	if (info->return_btype & expected_btypes) {
166 		return (AE_OK);
167 	}
168 
169 	/*
170 	 * At this point, we know that the type of the returned object was not
171 	 * one of the expected types for this predefined name. Attempt to
172 	 * repair the object by converting it to one of the expected object
173 	 * types for this predefined name.
174 	 */
175 
176 	/*
177 	 * If there is no return value, check if we require a return value for
178 	 * this predefined name. Either one return value is expected, or none,
179 	 * for both methods and other objects.
180 	 *
181 	 * Try to fix if there was no return object. Warning if failed to fix.
182 	 */
183 	if (!return_object) {
184 		if (expected_btypes) {
185 			if (!(expected_btypes & ACPI_RTYPE_NONE) &&
186 			    package_index != ACPI_NOT_PACKAGE_ELEMENT) {
187 				ACPI_WARN_PREDEFINED((AE_INFO,
188 						      info->full_pathname,
189 						      ACPI_WARN_ALWAYS,
190 						      "Found unexpected NULL package element"));
191 
192 				status =
193 				    acpi_ns_repair_null_element(info,
194 								expected_btypes,
195 								package_index,
196 								return_object_ptr);
197 				if (ACPI_SUCCESS(status)) {
198 					return (AE_OK);	/* Repair was successful */
199 				}
200 			}
201 
202 			if (expected_btypes != ACPI_RTYPE_NONE) {
203 				ACPI_WARN_PREDEFINED((AE_INFO,
204 						      info->full_pathname,
205 						      ACPI_WARN_ALWAYS,
206 						      "Missing expected return value"));
207 				return (AE_AML_NO_RETURN_VALUE);
208 			}
209 		}
210 	}
211 
212 	if (expected_btypes & ACPI_RTYPE_INTEGER) {
213 		status = acpi_ns_convert_to_integer(return_object, &new_object);
214 		if (ACPI_SUCCESS(status)) {
215 			goto object_repaired;
216 		}
217 	}
218 	if (expected_btypes & ACPI_RTYPE_STRING) {
219 		status = acpi_ns_convert_to_string(return_object, &new_object);
220 		if (ACPI_SUCCESS(status)) {
221 			goto object_repaired;
222 		}
223 	}
224 	if (expected_btypes & ACPI_RTYPE_BUFFER) {
225 		status = acpi_ns_convert_to_buffer(return_object, &new_object);
226 		if (ACPI_SUCCESS(status)) {
227 			goto object_repaired;
228 		}
229 	}
230 	if (expected_btypes & ACPI_RTYPE_PACKAGE) {
231 		/*
232 		 * A package is expected. We will wrap the existing object with a
233 		 * new package object. It is often the case that if a variable-length
234 		 * package is required, but there is only a single object needed, the
235 		 * BIOS will return that object instead of wrapping it with a Package
236 		 * object. Note: after the wrapping, the package will be validated
237 		 * for correct contents (expected object type or types).
238 		 */
239 		status =
240 		    acpi_ns_wrap_with_package(info, return_object, &new_object);
241 		if (ACPI_SUCCESS(status)) {
242 			/*
243 			 * The original object just had its reference count
244 			 * incremented for being inserted into the new package.
245 			 */
246 			*return_object_ptr = new_object;	/* New Package object */
247 			info->return_flags |= ACPI_OBJECT_REPAIRED;
248 			return (AE_OK);
249 		}
250 	}
251 
252 	/* We cannot repair this object */
253 
254 	return (AE_AML_OPERAND_TYPE);
255 
256 object_repaired:
257 
258 	/* Object was successfully repaired */
259 
260 	if (package_index != ACPI_NOT_PACKAGE_ELEMENT) {
261 
262 		/* Update reference count of new object */
263 
264 		if (!(info->return_flags & ACPI_OBJECT_WRAPPED)) {
265 			new_object->common.reference_count =
266 			    return_object->common.reference_count;
267 		}
268 
269 		ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
270 				  "%s: Converted %s to expected %s at Package index %u\n",
271 				  info->full_pathname,
272 				  acpi_ut_get_object_type_name(return_object),
273 				  acpi_ut_get_object_type_name(new_object),
274 				  package_index));
275 	} else {
276 		ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
277 				  "%s: Converted %s to expected %s\n",
278 				  info->full_pathname,
279 				  acpi_ut_get_object_type_name(return_object),
280 				  acpi_ut_get_object_type_name(new_object)));
281 	}
282 
283 	/* Delete old object, install the new return object */
284 
285 	acpi_ut_remove_reference(return_object);
286 	*return_object_ptr = new_object;
287 	info->return_flags |= ACPI_OBJECT_REPAIRED;
288 	return (AE_OK);
289 }
290 
291 /******************************************************************************
292  *
293  * FUNCTION:    acpi_ns_match_simple_repair
294  *
295  * PARAMETERS:  node                - Namespace node for the method/object
296  *              return_btype        - Object type that was returned
297  *              package_index       - Index of object within parent package (if
298  *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
299  *                                    otherwise)
300  *
301  * RETURN:      Pointer to entry in repair table. NULL indicates not found.
302  *
303  * DESCRIPTION: Check an object name against the repairable object list.
304  *
305  *****************************************************************************/
306 
307 static const struct acpi_simple_repair_info *acpi_ns_match_simple_repair(struct
308 									 acpi_namespace_node
309 									 *node,
310 									 u32
311 									 return_btype,
312 									 u32
313 									 package_index)
314 {
315 	const struct acpi_simple_repair_info *this_name;
316 
317 	/* Search info table for a repairable predefined method/object name */
318 
319 	this_name = acpi_object_repair_info;
320 	while (this_name->object_converter) {
321 		if (ACPI_COMPARE_NAMESEG(node->name.ascii, this_name->name)) {
322 
323 			/* Check if we can actually repair this name/type combination */
324 
325 			if ((return_btype & this_name->unexpected_btypes) &&
326 			    (this_name->package_index ==
327 			     ACPI_ALL_PACKAGE_ELEMENTS
328 			     || package_index == this_name->package_index)) {
329 				return (this_name);
330 			}
331 
332 			return (NULL);
333 		}
334 
335 		this_name++;
336 	}
337 
338 	return (NULL);		/* Name was not found in the repair table */
339 }
340 
341 /*******************************************************************************
342  *
343  * FUNCTION:    acpi_ns_repair_null_element
344  *
345  * PARAMETERS:  info                - Method execution information block
346  *              expected_btypes     - Object types expected
347  *              package_index       - Index of object within parent package (if
348  *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
349  *                                    otherwise)
350  *              return_object_ptr   - Pointer to the object returned from the
351  *                                    evaluation of a method or object
352  *
353  * RETURN:      Status. AE_OK if repair was successful.
354  *
355  * DESCRIPTION: Attempt to repair a NULL element of a returned Package object.
356  *
357  ******************************************************************************/
358 
359 acpi_status
360 acpi_ns_repair_null_element(struct acpi_evaluate_info *info,
361 			    u32 expected_btypes,
362 			    u32 package_index,
363 			    union acpi_operand_object **return_object_ptr)
364 {
365 	union acpi_operand_object *return_object = *return_object_ptr;
366 	union acpi_operand_object *new_object;
367 
368 	ACPI_FUNCTION_NAME(ns_repair_null_element);
369 
370 	/* No repair needed if return object is non-NULL */
371 
372 	if (return_object) {
373 		return (AE_OK);
374 	}
375 
376 	/*
377 	 * Attempt to repair a NULL element of a Package object. This applies to
378 	 * predefined names that return a fixed-length package and each element
379 	 * is required. It does not apply to variable-length packages where NULL
380 	 * elements are allowed, especially at the end of the package.
381 	 */
382 	if (expected_btypes & ACPI_RTYPE_INTEGER) {
383 
384 		/* Need an integer - create a zero-value integer */
385 
386 		new_object = acpi_ut_create_integer_object((u64)0);
387 	} else if (expected_btypes & ACPI_RTYPE_STRING) {
388 
389 		/* Need a string - create a NULL string */
390 
391 		new_object = acpi_ut_create_string_object(0);
392 	} else if (expected_btypes & ACPI_RTYPE_BUFFER) {
393 
394 		/* Need a buffer - create a zero-length buffer */
395 
396 		new_object = acpi_ut_create_buffer_object(0);
397 	} else {
398 		/* Error for all other expected types */
399 
400 		return (AE_AML_OPERAND_TYPE);
401 	}
402 
403 	if (!new_object) {
404 		return (AE_NO_MEMORY);
405 	}
406 
407 	/* Set the reference count according to the parent Package object */
408 
409 	new_object->common.reference_count =
410 	    info->parent_package->common.reference_count;
411 
412 	ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
413 			  "%s: Converted NULL package element to expected %s at index %u\n",
414 			  info->full_pathname,
415 			  acpi_ut_get_object_type_name(new_object),
416 			  package_index));
417 
418 	*return_object_ptr = new_object;
419 	info->return_flags |= ACPI_OBJECT_REPAIRED;
420 	return (AE_OK);
421 }
422 
423 /******************************************************************************
424  *
425  * FUNCTION:    acpi_ns_remove_null_elements
426  *
427  * PARAMETERS:  info                - Method execution information block
428  *              package_type        - An acpi_return_package_types value
429  *              obj_desc            - A Package object
430  *
431  * RETURN:      None.
432  *
433  * DESCRIPTION: Remove all NULL package elements from packages that contain
434  *              a variable number of subpackages. For these types of
435  *              packages, NULL elements can be safely removed.
436  *
437  *****************************************************************************/
438 
439 void
440 acpi_ns_remove_null_elements(struct acpi_evaluate_info *info,
441 			     u8 package_type,
442 			     union acpi_operand_object *obj_desc)
443 {
444 	union acpi_operand_object **source;
445 	union acpi_operand_object **dest;
446 	u32 count;
447 	u32 new_count;
448 	u32 i;
449 
450 	ACPI_FUNCTION_NAME(ns_remove_null_elements);
451 
452 	/*
453 	 * We can safely remove all NULL elements from these package types:
454 	 * PTYPE1_VAR packages contain a variable number of simple data types.
455 	 * PTYPE2 packages contain a variable number of subpackages.
456 	 */
457 	switch (package_type) {
458 	case ACPI_PTYPE1_VAR:
459 	case ACPI_PTYPE2:
460 	case ACPI_PTYPE2_COUNT:
461 	case ACPI_PTYPE2_PKG_COUNT:
462 	case ACPI_PTYPE2_FIXED:
463 	case ACPI_PTYPE2_MIN:
464 	case ACPI_PTYPE2_REV_FIXED:
465 	case ACPI_PTYPE2_FIX_VAR:
466 		break;
467 
468 	default:
469 	case ACPI_PTYPE2_VAR_VAR:
470 	case ACPI_PTYPE1_FIXED:
471 	case ACPI_PTYPE1_OPTION:
472 		return;
473 	}
474 
475 	count = obj_desc->package.count;
476 	new_count = count;
477 
478 	source = obj_desc->package.elements;
479 	dest = source;
480 
481 	/* Examine all elements of the package object, remove nulls */
482 
483 	for (i = 0; i < count; i++) {
484 		if (!*source) {
485 			new_count--;
486 		} else {
487 			*dest = *source;
488 			dest++;
489 		}
490 
491 		source++;
492 	}
493 
494 	/* Update parent package if any null elements were removed */
495 
496 	if (new_count < count) {
497 		ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
498 				  "%s: Found and removed %u NULL elements\n",
499 				  info->full_pathname, (count - new_count)));
500 
501 		/* NULL terminate list and update the package count */
502 
503 		*dest = NULL;
504 		obj_desc->package.count = new_count;
505 	}
506 }
507 
508 /*******************************************************************************
509  *
510  * FUNCTION:    acpi_ns_wrap_with_package
511  *
512  * PARAMETERS:  info                - Method execution information block
513  *              original_object     - Pointer to the object to repair.
514  *              obj_desc_ptr        - The new package object is returned here
515  *
516  * RETURN:      Status, new object in *obj_desc_ptr
517  *
518  * DESCRIPTION: Repair a common problem with objects that are defined to
519  *              return a variable-length Package of sub-objects. If there is
520  *              only one sub-object, some BIOS code mistakenly simply declares
521  *              the single object instead of a Package with one sub-object.
522  *              This function attempts to repair this error by wrapping a
523  *              Package object around the original object, creating the
524  *              correct and expected Package with one sub-object.
525  *
526  *              Names that can be repaired in this manner include:
527  *              _ALR, _CSD, _HPX, _MLS, _PLD, _PRT, _PSS, _TRT, _TSS,
528  *              _BCL, _DOD, _FIX, _Sx
529  *
530  ******************************************************************************/
531 
532 acpi_status
533 acpi_ns_wrap_with_package(struct acpi_evaluate_info *info,
534 			  union acpi_operand_object *original_object,
535 			  union acpi_operand_object **obj_desc_ptr)
536 {
537 	union acpi_operand_object *pkg_obj_desc;
538 
539 	ACPI_FUNCTION_NAME(ns_wrap_with_package);
540 
541 	/*
542 	 * Create the new outer package and populate it. The new
543 	 * package will have a single element, the lone sub-object.
544 	 */
545 	pkg_obj_desc = acpi_ut_create_package_object(1);
546 	if (!pkg_obj_desc) {
547 		return (AE_NO_MEMORY);
548 	}
549 
550 	pkg_obj_desc->package.elements[0] = original_object;
551 
552 	ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
553 			  "%s: Wrapped %s with expected Package object\n",
554 			  info->full_pathname,
555 			  acpi_ut_get_object_type_name(original_object)));
556 
557 	/* Return the new object in the object pointer */
558 
559 	*obj_desc_ptr = pkg_obj_desc;
560 	info->return_flags |= ACPI_OBJECT_REPAIRED | ACPI_OBJECT_WRAPPED;
561 	return (AE_OK);
562 }
563