xref: /openbmc/linux/drivers/acpi/acpica/nspredef.c (revision f3539c12)
1 /******************************************************************************
2  *
3  * Module Name: nspredef - Validation of ACPI predefined methods and objects
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2016, 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 #define ACPI_CREATE_PREDEFINED_TABLE
45 
46 #include <acpi/acpi.h>
47 #include "accommon.h"
48 #include "acnamesp.h"
49 #include "acpredef.h"
50 
51 #define _COMPONENT          ACPI_NAMESPACE
52 ACPI_MODULE_NAME("nspredef")
53 
54 /*******************************************************************************
55  *
56  * This module validates predefined ACPI objects that appear in the namespace,
57  * at the time they are evaluated (via acpi_evaluate_object). The purpose of this
58  * validation is to detect problems with BIOS-exposed predefined ACPI objects
59  * before the results are returned to the ACPI-related drivers.
60  *
61  * There are several areas that are validated:
62  *
63  *  1) The number of input arguments as defined by the method/object in the
64  *     ASL is validated against the ACPI specification.
65  *  2) The type of the return object (if any) is validated against the ACPI
66  *     specification.
67  *  3) For returned package objects, the count of package elements is
68  *     validated, as well as the type of each package element. Nested
69  *     packages are supported.
70  *
71  * For any problems found, a warning message is issued.
72  *
73  ******************************************************************************/
74 /* Local prototypes */
75 static acpi_status
76 acpi_ns_check_reference(struct acpi_evaluate_info *info,
77 			union acpi_operand_object *return_object);
78 
79 static u32 acpi_ns_get_bitmapped_type(union acpi_operand_object *return_object);
80 
81 /*******************************************************************************
82  *
83  * FUNCTION:    acpi_ns_check_return_value
84  *
85  * PARAMETERS:  node            - Namespace node for the method/object
86  *              info            - Method execution information block
87  *              user_param_count - Number of parameters actually passed
88  *              return_status   - Status from the object evaluation
89  *              return_object_ptr - Pointer to the object returned from the
90  *                                evaluation of a method or object
91  *
92  * RETURN:      Status
93  *
94  * DESCRIPTION: Check the value returned from a predefined name.
95  *
96  ******************************************************************************/
97 
98 acpi_status
99 acpi_ns_check_return_value(struct acpi_namespace_node *node,
100 			   struct acpi_evaluate_info *info,
101 			   u32 user_param_count,
102 			   acpi_status return_status,
103 			   union acpi_operand_object **return_object_ptr)
104 {
105 	acpi_status status;
106 	const union acpi_predefined_info *predefined;
107 
108 	/* If not a predefined name, we cannot validate the return object */
109 
110 	predefined = info->predefined;
111 	if (!predefined) {
112 		return (AE_OK);
113 	}
114 
115 	/*
116 	 * If the method failed or did not actually return an object, we cannot
117 	 * validate the return object
118 	 */
119 	if ((return_status != AE_OK) && (return_status != AE_CTRL_RETURN_VALUE)) {
120 		return (AE_OK);
121 	}
122 
123 	/*
124 	 * Return value validation and possible repair.
125 	 *
126 	 * 1) Don't perform return value validation/repair if this feature
127 	 * has been disabled via a global option.
128 	 *
129 	 * 2) We have a return value, but if one wasn't expected, just exit,
130 	 * this is not a problem. For example, if the "Implicit Return"
131 	 * feature is enabled, methods will always return a value.
132 	 *
133 	 * 3) If the return value can be of any type, then we cannot perform
134 	 * any validation, just exit.
135 	 */
136 	if (acpi_gbl_disable_auto_repair ||
137 	    (!predefined->info.expected_btypes) ||
138 	    (predefined->info.expected_btypes == ACPI_RTYPE_ALL)) {
139 		return (AE_OK);
140 	}
141 
142 	/*
143 	 * Check that the type of the main return object is what is expected
144 	 * for this predefined name
145 	 */
146 	status = acpi_ns_check_object_type(info, return_object_ptr,
147 					   predefined->info.expected_btypes,
148 					   ACPI_NOT_PACKAGE_ELEMENT);
149 	if (ACPI_FAILURE(status)) {
150 		goto exit;
151 	}
152 
153 	/*
154 	 *
155 	 * 4) If there is no return value and it is optional, just return
156 	 * AE_OK (_WAK).
157 	 */
158 	if (!(*return_object_ptr)) {
159 		goto exit;
160 	}
161 
162 	/*
163 	 * For returned Package objects, check the type of all sub-objects.
164 	 * Note: Package may have been newly created by call above.
165 	 */
166 	if ((*return_object_ptr)->common.type == ACPI_TYPE_PACKAGE) {
167 		info->parent_package = *return_object_ptr;
168 		status = acpi_ns_check_package(info, return_object_ptr);
169 		if (ACPI_FAILURE(status)) {
170 
171 			/* We might be able to fix some errors */
172 
173 			if ((status != AE_AML_OPERAND_TYPE) &&
174 			    (status != AE_AML_OPERAND_VALUE)) {
175 				goto exit;
176 			}
177 		}
178 	}
179 
180 	/*
181 	 * The return object was OK, or it was successfully repaired above.
182 	 * Now make some additional checks such as verifying that package
183 	 * objects are sorted correctly (if required) or buffer objects have
184 	 * the correct data width (bytes vs. dwords). These repairs are
185 	 * performed on a per-name basis, i.e., the code is specific to
186 	 * particular predefined names.
187 	 */
188 	status = acpi_ns_complex_repairs(info, node, status, return_object_ptr);
189 
190 exit:
191 	/*
192 	 * If the object validation failed or if we successfully repaired one
193 	 * or more objects, mark the parent node to suppress further warning
194 	 * messages during the next evaluation of the same method/object.
195 	 */
196 	if (ACPI_FAILURE(status) || (info->return_flags & ACPI_OBJECT_REPAIRED)) {
197 		node->flags |= ANOBJ_EVALUATED;
198 	}
199 
200 	return (status);
201 }
202 
203 /*******************************************************************************
204  *
205  * FUNCTION:    acpi_ns_check_object_type
206  *
207  * PARAMETERS:  info            - Method execution information block
208  *              return_object_ptr - Pointer to the object returned from the
209  *                                evaluation of a method or object
210  *              expected_btypes - Bitmap of expected return type(s)
211  *              package_index   - Index of object within parent package (if
212  *                                applicable - ACPI_NOT_PACKAGE_ELEMENT
213  *                                otherwise)
214  *
215  * RETURN:      Status
216  *
217  * DESCRIPTION: Check the type of the return object against the expected object
218  *              type(s). Use of Btype allows multiple expected object types.
219  *
220  ******************************************************************************/
221 
222 acpi_status
223 acpi_ns_check_object_type(struct acpi_evaluate_info *info,
224 			  union acpi_operand_object **return_object_ptr,
225 			  u32 expected_btypes, u32 package_index)
226 {
227 	union acpi_operand_object *return_object = *return_object_ptr;
228 	acpi_status status = AE_OK;
229 	char type_buffer[96];	/* Room for 10 types */
230 
231 	/* A Namespace node should not get here, but make sure */
232 
233 	if (return_object &&
234 	    ACPI_GET_DESCRIPTOR_TYPE(return_object) == ACPI_DESC_TYPE_NAMED) {
235 		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
236 				      info->node_flags,
237 				      "Invalid return type - Found a Namespace node [%4.4s] type %s",
238 				      return_object->node.name.ascii,
239 				      acpi_ut_get_type_name(return_object->node.
240 							    type)));
241 		return (AE_AML_OPERAND_TYPE);
242 	}
243 
244 	/*
245 	 * Convert the object type (ACPI_TYPE_xxx) to a bitmapped object type.
246 	 * The bitmapped type allows multiple possible return types.
247 	 *
248 	 * Note, the cases below must handle all of the possible types returned
249 	 * from all of the predefined names (including elements of returned
250 	 * packages)
251 	 */
252 	info->return_btype = acpi_ns_get_bitmapped_type(return_object);
253 	if (info->return_btype == ACPI_RTYPE_ANY) {
254 
255 		/* Not one of the supported objects, must be incorrect */
256 		goto type_error_exit;
257 	}
258 
259 	/* For reference objects, check that the reference type is correct */
260 
261 	if ((info->return_btype & expected_btypes) == ACPI_RTYPE_REFERENCE) {
262 		status = acpi_ns_check_reference(info, return_object);
263 		return (status);
264 	}
265 
266 	/* Attempt simple repair of the returned object if necessary */
267 
268 	status = acpi_ns_simple_repair(info, expected_btypes,
269 				       package_index, return_object_ptr);
270 	if (ACPI_SUCCESS(status)) {
271 		return (AE_OK);	/* Successful repair */
272 	}
273 
274 type_error_exit:
275 
276 	/* Create a string with all expected types for this predefined object */
277 
278 	acpi_ut_get_expected_return_types(type_buffer, expected_btypes);
279 
280 	if (!return_object) {
281 		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
282 				      info->node_flags,
283 				      "Expected return object of type %s",
284 				      type_buffer));
285 	} else if (package_index == ACPI_NOT_PACKAGE_ELEMENT) {
286 		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
287 				      info->node_flags,
288 				      "Return type mismatch - found %s, expected %s",
289 				      acpi_ut_get_object_type_name
290 				      (return_object), type_buffer));
291 	} else {
292 		ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname,
293 				      info->node_flags,
294 				      "Return Package type mismatch at index %u - "
295 				      "found %s, expected %s", package_index,
296 				      acpi_ut_get_object_type_name
297 				      (return_object), type_buffer));
298 	}
299 
300 	return (AE_AML_OPERAND_TYPE);
301 }
302 
303 /*******************************************************************************
304  *
305  * FUNCTION:    acpi_ns_check_reference
306  *
307  * PARAMETERS:  info            - Method execution information block
308  *              return_object   - Object returned from the evaluation of a
309  *                                method or object
310  *
311  * RETURN:      Status
312  *
313  * DESCRIPTION: Check a returned reference object for the correct reference
314  *              type. The only reference type that can be returned from a
315  *              predefined method is a named reference. All others are invalid.
316  *
317  ******************************************************************************/
318 
319 static acpi_status
320 acpi_ns_check_reference(struct acpi_evaluate_info *info,
321 			union acpi_operand_object *return_object)
322 {
323 
324 	/*
325 	 * Check the reference object for the correct reference type (opcode).
326 	 * The only type of reference that can be converted to an union acpi_object is
327 	 * a reference to a named object (reference class: NAME)
328 	 */
329 	if (return_object->reference.class == ACPI_REFCLASS_NAME) {
330 		return (AE_OK);
331 	}
332 
333 	ACPI_WARN_PREDEFINED((AE_INFO, info->full_pathname, info->node_flags,
334 			      "Return type mismatch - unexpected reference object type [%s] %2.2X",
335 			      acpi_ut_get_reference_name(return_object),
336 			      return_object->reference.class));
337 
338 	return (AE_AML_OPERAND_TYPE);
339 }
340 
341 /*******************************************************************************
342  *
343  * FUNCTION:    acpi_ns_get_bitmapped_type
344  *
345  * PARAMETERS:  return_object   - Object returned from method/obj evaluation
346  *
347  * RETURN:      Object return type. ACPI_RTYPE_ANY indicates that the object
348  *              type is not supported. ACPI_RTYPE_NONE indicates that no
349  *              object was returned (return_object is NULL).
350  *
351  * DESCRIPTION: Convert object type into a bitmapped object return type.
352  *
353  ******************************************************************************/
354 
355 static u32 acpi_ns_get_bitmapped_type(union acpi_operand_object *return_object)
356 {
357 	u32 return_btype;
358 
359 	if (!return_object) {
360 		return (ACPI_RTYPE_NONE);
361 	}
362 
363 	/* Map acpi_object_type to internal bitmapped type */
364 
365 	switch (return_object->common.type) {
366 	case ACPI_TYPE_INTEGER:
367 
368 		return_btype = ACPI_RTYPE_INTEGER;
369 		break;
370 
371 	case ACPI_TYPE_BUFFER:
372 
373 		return_btype = ACPI_RTYPE_BUFFER;
374 		break;
375 
376 	case ACPI_TYPE_STRING:
377 
378 		return_btype = ACPI_RTYPE_STRING;
379 		break;
380 
381 	case ACPI_TYPE_PACKAGE:
382 
383 		return_btype = ACPI_RTYPE_PACKAGE;
384 		break;
385 
386 	case ACPI_TYPE_LOCAL_REFERENCE:
387 
388 		return_btype = ACPI_RTYPE_REFERENCE;
389 		break;
390 
391 	default:
392 
393 		/* Not one of the supported objects, must be incorrect */
394 
395 		return_btype = ACPI_RTYPE_ANY;
396 		break;
397 	}
398 
399 	return (return_btype);
400 }
401