xref: /openbmc/linux/drivers/acpi/acpica/nsrepair.c (revision 842ed298)
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 - 2020, 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 && (!(expected_btypes & ACPI_RTYPE_NONE))) {
185 			if (package_index != ACPI_NOT_PACKAGE_ELEMENT) {
186 				ACPI_WARN_PREDEFINED((AE_INFO,
187 						      info->full_pathname,
188 						      ACPI_WARN_ALWAYS,
189 						      "Found unexpected NULL package element"));
190 
191 				status =
192 				    acpi_ns_repair_null_element(info,
193 								expected_btypes,
194 								package_index,
195 								return_object_ptr);
196 				if (ACPI_SUCCESS(status)) {
197 					return (AE_OK);	/* Repair was successful */
198 				}
199 			} else {
200 				ACPI_WARN_PREDEFINED((AE_INFO,
201 						      info->full_pathname,
202 						      ACPI_WARN_ALWAYS,
203 						      "Missing expected return value"));
204 			}
205 
206 			return (AE_AML_NO_RETURN_VALUE);
207 		}
208 	}
209 
210 	if (expected_btypes & ACPI_RTYPE_INTEGER) {
211 		status = acpi_ns_convert_to_integer(return_object, &new_object);
212 		if (ACPI_SUCCESS(status)) {
213 			goto object_repaired;
214 		}
215 	}
216 	if (expected_btypes & ACPI_RTYPE_STRING) {
217 		status = acpi_ns_convert_to_string(return_object, &new_object);
218 		if (ACPI_SUCCESS(status)) {
219 			goto object_repaired;
220 		}
221 	}
222 	if (expected_btypes & ACPI_RTYPE_BUFFER) {
223 		status = acpi_ns_convert_to_buffer(return_object, &new_object);
224 		if (ACPI_SUCCESS(status)) {
225 			goto object_repaired;
226 		}
227 	}
228 	if (expected_btypes & ACPI_RTYPE_PACKAGE) {
229 		/*
230 		 * A package is expected. We will wrap the existing object with a
231 		 * new package object. It is often the case that if a variable-length
232 		 * package is required, but there is only a single object needed, the
233 		 * BIOS will return that object instead of wrapping it with a Package
234 		 * object. Note: after the wrapping, the package will be validated
235 		 * for correct contents (expected object type or types).
236 		 */
237 		status =
238 		    acpi_ns_wrap_with_package(info, return_object, &new_object);
239 		if (ACPI_SUCCESS(status)) {
240 			/*
241 			 * The original object just had its reference count
242 			 * incremented for being inserted into the new package.
243 			 */
244 			*return_object_ptr = new_object;	/* New Package object */
245 			info->return_flags |= ACPI_OBJECT_REPAIRED;
246 			return (AE_OK);
247 		}
248 	}
249 
250 	/* We cannot repair this object */
251 
252 	return (AE_AML_OPERAND_TYPE);
253 
254 object_repaired:
255 
256 	/* Object was successfully repaired */
257 
258 	if (package_index != ACPI_NOT_PACKAGE_ELEMENT) {
259 
260 		/* Update reference count of new object */
261 
262 		if (!(info->return_flags & ACPI_OBJECT_WRAPPED)) {
263 			new_object->common.reference_count =
264 			    return_object->common.reference_count;
265 		}
266 
267 		ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
268 				  "%s: Converted %s to expected %s at Package index %u\n",
269 				  info->full_pathname,
270 				  acpi_ut_get_object_type_name(return_object),
271 				  acpi_ut_get_object_type_name(new_object),
272 				  package_index));
273 	} else {
274 		ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
275 				  "%s: Converted %s to expected %s\n",
276 				  info->full_pathname,
277 				  acpi_ut_get_object_type_name(return_object),
278 				  acpi_ut_get_object_type_name(new_object)));
279 	}
280 
281 	/* Delete old object, install the new return object */
282 
283 	acpi_ut_remove_reference(return_object);
284 	*return_object_ptr = new_object;
285 	info->return_flags |= ACPI_OBJECT_REPAIRED;
286 	return (AE_OK);
287 }
288 
289 /******************************************************************************
290  *
291  * FUNCTION:    acpi_ns_match_simple_repair
292  *
293  * PARAMETERS:  node                - Namespace node for the method/object
294  *              return_btype        - Object type that was returned
295  *              package_index       - Index of object within parent package (if
296  *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
297  *                                    otherwise)
298  *
299  * RETURN:      Pointer to entry in repair table. NULL indicates not found.
300  *
301  * DESCRIPTION: Check an object name against the repairable object list.
302  *
303  *****************************************************************************/
304 
305 static const struct acpi_simple_repair_info *acpi_ns_match_simple_repair(struct
306 									 acpi_namespace_node
307 									 *node,
308 									 u32
309 									 return_btype,
310 									 u32
311 									 package_index)
312 {
313 	const struct acpi_simple_repair_info *this_name;
314 
315 	/* Search info table for a repairable predefined method/object name */
316 
317 	this_name = acpi_object_repair_info;
318 	while (this_name->object_converter) {
319 		if (ACPI_COMPARE_NAMESEG(node->name.ascii, this_name->name)) {
320 
321 			/* Check if we can actually repair this name/type combination */
322 
323 			if ((return_btype & this_name->unexpected_btypes) &&
324 			    (this_name->package_index ==
325 			     ACPI_ALL_PACKAGE_ELEMENTS
326 			     || package_index == this_name->package_index)) {
327 				return (this_name);
328 			}
329 
330 			return (NULL);
331 		}
332 
333 		this_name++;
334 	}
335 
336 	return (NULL);		/* Name was not found in the repair table */
337 }
338 
339 /*******************************************************************************
340  *
341  * FUNCTION:    acpi_ns_repair_null_element
342  *
343  * PARAMETERS:  info                - Method execution information block
344  *              expected_btypes     - Object types expected
345  *              package_index       - Index of object within parent package (if
346  *                                    applicable - ACPI_NOT_PACKAGE_ELEMENT
347  *                                    otherwise)
348  *              return_object_ptr   - Pointer to the object returned from the
349  *                                    evaluation of a method or object
350  *
351  * RETURN:      Status. AE_OK if repair was successful.
352  *
353  * DESCRIPTION: Attempt to repair a NULL element of a returned Package object.
354  *
355  ******************************************************************************/
356 
357 acpi_status
358 acpi_ns_repair_null_element(struct acpi_evaluate_info *info,
359 			    u32 expected_btypes,
360 			    u32 package_index,
361 			    union acpi_operand_object **return_object_ptr)
362 {
363 	union acpi_operand_object *return_object = *return_object_ptr;
364 	union acpi_operand_object *new_object;
365 
366 	ACPI_FUNCTION_NAME(ns_repair_null_element);
367 
368 	/* No repair needed if return object is non-NULL */
369 
370 	if (return_object) {
371 		return (AE_OK);
372 	}
373 
374 	/*
375 	 * Attempt to repair a NULL element of a Package object. This applies to
376 	 * predefined names that return a fixed-length package and each element
377 	 * is required. It does not apply to variable-length packages where NULL
378 	 * elements are allowed, especially at the end of the package.
379 	 */
380 	if (expected_btypes & ACPI_RTYPE_INTEGER) {
381 
382 		/* Need an integer - create a zero-value integer */
383 
384 		new_object = acpi_ut_create_integer_object((u64)0);
385 	} else if (expected_btypes & ACPI_RTYPE_STRING) {
386 
387 		/* Need a string - create a NULL string */
388 
389 		new_object = acpi_ut_create_string_object(0);
390 	} else if (expected_btypes & ACPI_RTYPE_BUFFER) {
391 
392 		/* Need a buffer - create a zero-length buffer */
393 
394 		new_object = acpi_ut_create_buffer_object(0);
395 	} else {
396 		/* Error for all other expected types */
397 
398 		return (AE_AML_OPERAND_TYPE);
399 	}
400 
401 	if (!new_object) {
402 		return (AE_NO_MEMORY);
403 	}
404 
405 	/* Set the reference count according to the parent Package object */
406 
407 	new_object->common.reference_count =
408 	    info->parent_package->common.reference_count;
409 
410 	ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
411 			  "%s: Converted NULL package element to expected %s at index %u\n",
412 			  info->full_pathname,
413 			  acpi_ut_get_object_type_name(new_object),
414 			  package_index));
415 
416 	*return_object_ptr = new_object;
417 	info->return_flags |= ACPI_OBJECT_REPAIRED;
418 	return (AE_OK);
419 }
420 
421 /******************************************************************************
422  *
423  * FUNCTION:    acpi_ns_remove_null_elements
424  *
425  * PARAMETERS:  info                - Method execution information block
426  *              package_type        - An acpi_return_package_types value
427  *              obj_desc            - A Package object
428  *
429  * RETURN:      None.
430  *
431  * DESCRIPTION: Remove all NULL package elements from packages that contain
432  *              a variable number of subpackages. For these types of
433  *              packages, NULL elements can be safely removed.
434  *
435  *****************************************************************************/
436 
437 void
438 acpi_ns_remove_null_elements(struct acpi_evaluate_info *info,
439 			     u8 package_type,
440 			     union acpi_operand_object *obj_desc)
441 {
442 	union acpi_operand_object **source;
443 	union acpi_operand_object **dest;
444 	u32 count;
445 	u32 new_count;
446 	u32 i;
447 
448 	ACPI_FUNCTION_NAME(ns_remove_null_elements);
449 
450 	/*
451 	 * We can safely remove all NULL elements from these package types:
452 	 * PTYPE1_VAR packages contain a variable number of simple data types.
453 	 * PTYPE2 packages contain a variable number of subpackages.
454 	 */
455 	switch (package_type) {
456 	case ACPI_PTYPE1_VAR:
457 	case ACPI_PTYPE2:
458 	case ACPI_PTYPE2_COUNT:
459 	case ACPI_PTYPE2_PKG_COUNT:
460 	case ACPI_PTYPE2_FIXED:
461 	case ACPI_PTYPE2_MIN:
462 	case ACPI_PTYPE2_REV_FIXED:
463 	case ACPI_PTYPE2_FIX_VAR:
464 		break;
465 
466 	default:
467 	case ACPI_PTYPE2_VAR_VAR:
468 	case ACPI_PTYPE1_FIXED:
469 	case ACPI_PTYPE1_OPTION:
470 		return;
471 	}
472 
473 	count = obj_desc->package.count;
474 	new_count = count;
475 
476 	source = obj_desc->package.elements;
477 	dest = source;
478 
479 	/* Examine all elements of the package object, remove nulls */
480 
481 	for (i = 0; i < count; i++) {
482 		if (!*source) {
483 			new_count--;
484 		} else {
485 			*dest = *source;
486 			dest++;
487 		}
488 
489 		source++;
490 	}
491 
492 	/* Update parent package if any null elements were removed */
493 
494 	if (new_count < count) {
495 		ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
496 				  "%s: Found and removed %u NULL elements\n",
497 				  info->full_pathname, (count - new_count)));
498 
499 		/* NULL terminate list and update the package count */
500 
501 		*dest = NULL;
502 		obj_desc->package.count = new_count;
503 	}
504 }
505 
506 /*******************************************************************************
507  *
508  * FUNCTION:    acpi_ns_wrap_with_package
509  *
510  * PARAMETERS:  info                - Method execution information block
511  *              original_object     - Pointer to the object to repair.
512  *              obj_desc_ptr        - The new package object is returned here
513  *
514  * RETURN:      Status, new object in *obj_desc_ptr
515  *
516  * DESCRIPTION: Repair a common problem with objects that are defined to
517  *              return a variable-length Package of sub-objects. If there is
518  *              only one sub-object, some BIOS code mistakenly simply declares
519  *              the single object instead of a Package with one sub-object.
520  *              This function attempts to repair this error by wrapping a
521  *              Package object around the original object, creating the
522  *              correct and expected Package with one sub-object.
523  *
524  *              Names that can be repaired in this manner include:
525  *              _ALR, _CSD, _HPX, _MLS, _PLD, _PRT, _PSS, _TRT, _TSS,
526  *              _BCL, _DOD, _FIX, _Sx
527  *
528  ******************************************************************************/
529 
530 acpi_status
531 acpi_ns_wrap_with_package(struct acpi_evaluate_info *info,
532 			  union acpi_operand_object *original_object,
533 			  union acpi_operand_object **obj_desc_ptr)
534 {
535 	union acpi_operand_object *pkg_obj_desc;
536 
537 	ACPI_FUNCTION_NAME(ns_wrap_with_package);
538 
539 	/*
540 	 * Create the new outer package and populate it. The new
541 	 * package will have a single element, the lone sub-object.
542 	 */
543 	pkg_obj_desc = acpi_ut_create_package_object(1);
544 	if (!pkg_obj_desc) {
545 		return (AE_NO_MEMORY);
546 	}
547 
548 	pkg_obj_desc->package.elements[0] = original_object;
549 
550 	ACPI_DEBUG_PRINT((ACPI_DB_REPAIR,
551 			  "%s: Wrapped %s with expected Package object\n",
552 			  info->full_pathname,
553 			  acpi_ut_get_object_type_name(original_object)));
554 
555 	/* Return the new object in the object pointer */
556 
557 	*obj_desc_ptr = pkg_obj_desc;
558 	info->return_flags |= ACPI_OBJECT_REPAIRED | ACPI_OBJECT_WRAPPED;
559 	return (AE_OK);
560 }
561