xref: /openbmc/linux/drivers/acpi/acpica/exresolv.c (revision b78412b8)
1 /******************************************************************************
2  *
3  * Module Name: exresolv - AML Interpreter object resolution
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 "amlcode.h"
47 #include "acdispat.h"
48 #include "acinterp.h"
49 #include "acnamesp.h"
50 
51 #define _COMPONENT          ACPI_EXECUTER
52 ACPI_MODULE_NAME("exresolv")
53 
54 /* Local prototypes */
55 static acpi_status
56 acpi_ex_resolve_object_to_value(union acpi_operand_object **stack_ptr,
57 				struct acpi_walk_state *walk_state);
58 
59 /*******************************************************************************
60  *
61  * FUNCTION:    acpi_ex_resolve_to_value
62  *
63  * PARAMETERS:  **stack_ptr         - Points to entry on obj_stack, which can
64  *                                    be either an (union acpi_operand_object *)
65  *                                    or an acpi_handle.
66  *              walk_state          - Current method state
67  *
68  * RETURN:      Status
69  *
70  * DESCRIPTION: Convert Reference objects to values
71  *
72  ******************************************************************************/
73 
74 acpi_status
75 acpi_ex_resolve_to_value(union acpi_operand_object **stack_ptr,
76 			 struct acpi_walk_state *walk_state)
77 {
78 	acpi_status status;
79 
80 	ACPI_FUNCTION_TRACE_PTR(ex_resolve_to_value, stack_ptr);
81 
82 	if (!stack_ptr || !*stack_ptr) {
83 		ACPI_ERROR((AE_INFO, "Internal - null pointer"));
84 		return_ACPI_STATUS(AE_AML_NO_OPERAND);
85 	}
86 
87 	/*
88 	 * The entity pointed to by the stack_ptr can be either
89 	 * 1) A valid union acpi_operand_object, or
90 	 * 2) A struct acpi_namespace_node (named_obj)
91 	 */
92 	if (ACPI_GET_DESCRIPTOR_TYPE(*stack_ptr) == ACPI_DESC_TYPE_OPERAND) {
93 		status = acpi_ex_resolve_object_to_value(stack_ptr, walk_state);
94 		if (ACPI_FAILURE(status)) {
95 			return_ACPI_STATUS(status);
96 		}
97 
98 		if (!*stack_ptr) {
99 			ACPI_ERROR((AE_INFO, "Internal - null pointer"));
100 			return_ACPI_STATUS(AE_AML_NO_OPERAND);
101 		}
102 	}
103 
104 	/*
105 	 * Object on the stack may have changed if acpi_ex_resolve_object_to_value()
106 	 * was called (i.e., we can't use an _else_ here.)
107 	 */
108 	if (ACPI_GET_DESCRIPTOR_TYPE(*stack_ptr) == ACPI_DESC_TYPE_NAMED) {
109 		status =
110 		    acpi_ex_resolve_node_to_value(ACPI_CAST_INDIRECT_PTR
111 						  (struct acpi_namespace_node,
112 						   stack_ptr), walk_state);
113 		if (ACPI_FAILURE(status)) {
114 			return_ACPI_STATUS(status);
115 		}
116 	}
117 
118 	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Resolved object %p\n", *stack_ptr));
119 	return_ACPI_STATUS(AE_OK);
120 }
121 
122 /*******************************************************************************
123  *
124  * FUNCTION:    acpi_ex_resolve_object_to_value
125  *
126  * PARAMETERS:  stack_ptr       - Pointer to an internal object
127  *              walk_state      - Current method state
128  *
129  * RETURN:      Status
130  *
131  * DESCRIPTION: Retrieve the value from an internal object. The Reference type
132  *              uses the associated AML opcode to determine the value.
133  *
134  ******************************************************************************/
135 
136 static acpi_status
137 acpi_ex_resolve_object_to_value(union acpi_operand_object **stack_ptr,
138 				struct acpi_walk_state *walk_state)
139 {
140 	acpi_status status = AE_OK;
141 	union acpi_operand_object *stack_desc;
142 	union acpi_operand_object *obj_desc = NULL;
143 	u8 ref_type;
144 
145 	ACPI_FUNCTION_TRACE(ex_resolve_object_to_value);
146 
147 	stack_desc = *stack_ptr;
148 
149 	/* This is an object of type union acpi_operand_object */
150 
151 	switch (stack_desc->common.type) {
152 	case ACPI_TYPE_LOCAL_REFERENCE:
153 
154 		ref_type = stack_desc->reference.class;
155 
156 		switch (ref_type) {
157 		case ACPI_REFCLASS_LOCAL:
158 		case ACPI_REFCLASS_ARG:
159 			/*
160 			 * Get the local from the method's state info
161 			 * Note: this increments the local's object reference count
162 			 */
163 			status = acpi_ds_method_data_get_value(ref_type,
164 							       stack_desc->
165 							       reference.value,
166 							       walk_state,
167 							       &obj_desc);
168 			if (ACPI_FAILURE(status)) {
169 				return_ACPI_STATUS(status);
170 			}
171 
172 			ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
173 					  "[Arg/Local %X] ValueObj is %p\n",
174 					  stack_desc->reference.value,
175 					  obj_desc));
176 
177 			/*
178 			 * Now we can delete the original Reference Object and
179 			 * replace it with the resolved value
180 			 */
181 			acpi_ut_remove_reference(stack_desc);
182 			*stack_ptr = obj_desc;
183 			break;
184 
185 		case ACPI_REFCLASS_INDEX:
186 
187 			switch (stack_desc->reference.target_type) {
188 			case ACPI_TYPE_BUFFER_FIELD:
189 
190 				/* Just return - do not dereference */
191 				break;
192 
193 			case ACPI_TYPE_PACKAGE:
194 
195 				/* If method call or copy_object - do not dereference */
196 
197 				if ((walk_state->opcode ==
198 				     AML_INT_METHODCALL_OP)
199 				    || (walk_state->opcode ==
200 					AML_COPY_OBJECT_OP)) {
201 					break;
202 				}
203 
204 				/* Otherwise, dereference the package_index to a package element */
205 
206 				obj_desc = *stack_desc->reference.where;
207 				if (obj_desc) {
208 					/*
209 					 * Valid object descriptor, copy pointer to return value
210 					 * (i.e., dereference the package index)
211 					 * Delete the ref object, increment the returned object
212 					 */
213 					acpi_ut_add_reference(obj_desc);
214 					*stack_ptr = obj_desc;
215 				} else {
216 					/*
217 					 * A NULL object descriptor means an uninitialized element of
218 					 * the package, can't dereference it
219 					 */
220 					ACPI_ERROR((AE_INFO,
221 						    "Attempt to dereference an Index to "
222 						    "NULL package element Idx=%p",
223 						    stack_desc));
224 					status = AE_AML_UNINITIALIZED_ELEMENT;
225 				}
226 				break;
227 
228 			default:
229 
230 				/* Invalid reference object */
231 
232 				ACPI_ERROR((AE_INFO,
233 					    "Unknown TargetType 0x%X in Index/Reference object %p",
234 					    stack_desc->reference.target_type,
235 					    stack_desc));
236 				status = AE_AML_INTERNAL;
237 				break;
238 			}
239 			break;
240 
241 		case ACPI_REFCLASS_REFOF:
242 		case ACPI_REFCLASS_DEBUG:
243 		case ACPI_REFCLASS_TABLE:
244 
245 			/* Just leave the object as-is, do not dereference */
246 
247 			break;
248 
249 		case ACPI_REFCLASS_NAME:	/* Reference to a named object */
250 
251 			/* Dereference the name */
252 
253 			if ((stack_desc->reference.node->type ==
254 			     ACPI_TYPE_DEVICE)
255 			    || (stack_desc->reference.node->type ==
256 				ACPI_TYPE_THERMAL)) {
257 
258 				/* These node types do not have 'real' subobjects */
259 
260 				*stack_ptr = (void *)stack_desc->reference.node;
261 			} else {
262 				/* Get the object pointed to by the namespace node */
263 
264 				*stack_ptr =
265 				    (stack_desc->reference.node)->object;
266 				acpi_ut_add_reference(*stack_ptr);
267 			}
268 
269 			acpi_ut_remove_reference(stack_desc);
270 			break;
271 
272 		default:
273 
274 			ACPI_ERROR((AE_INFO,
275 				    "Unknown Reference type 0x%X in %p",
276 				    ref_type, stack_desc));
277 			status = AE_AML_INTERNAL;
278 			break;
279 		}
280 		break;
281 
282 	case ACPI_TYPE_BUFFER:
283 
284 		status = acpi_ds_get_buffer_arguments(stack_desc);
285 		break;
286 
287 	case ACPI_TYPE_PACKAGE:
288 
289 		status = acpi_ds_get_package_arguments(stack_desc);
290 		break;
291 
292 	case ACPI_TYPE_BUFFER_FIELD:
293 	case ACPI_TYPE_LOCAL_REGION_FIELD:
294 	case ACPI_TYPE_LOCAL_BANK_FIELD:
295 	case ACPI_TYPE_LOCAL_INDEX_FIELD:
296 
297 		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
298 				  "FieldRead SourceDesc=%p Type=%X\n",
299 				  stack_desc, stack_desc->common.type));
300 
301 		status =
302 		    acpi_ex_read_data_from_field(walk_state, stack_desc,
303 						 &obj_desc);
304 
305 		/* Remove a reference to the original operand, then override */
306 
307 		acpi_ut_remove_reference(*stack_ptr);
308 		*stack_ptr = (void *)obj_desc;
309 		break;
310 
311 	default:
312 
313 		break;
314 	}
315 
316 	return_ACPI_STATUS(status);
317 }
318 
319 /*******************************************************************************
320  *
321  * FUNCTION:    acpi_ex_resolve_multiple
322  *
323  * PARAMETERS:  walk_state          - Current state (contains AML opcode)
324  *              operand             - Starting point for resolution
325  *              return_type         - Where the object type is returned
326  *              return_desc         - Where the resolved object is returned
327  *
328  * RETURN:      Status
329  *
330  * DESCRIPTION: Return the base object and type. Traverse a reference list if
331  *              necessary to get to the base object.
332  *
333  ******************************************************************************/
334 
335 acpi_status
336 acpi_ex_resolve_multiple(struct acpi_walk_state *walk_state,
337 			 union acpi_operand_object *operand,
338 			 acpi_object_type *return_type,
339 			 union acpi_operand_object **return_desc)
340 {
341 	union acpi_operand_object *obj_desc = ACPI_CAST_PTR(void, operand);
342 	struct acpi_namespace_node *node =
343 	    ACPI_CAST_PTR(struct acpi_namespace_node, operand);
344 	acpi_object_type type;
345 	acpi_status status;
346 
347 	ACPI_FUNCTION_TRACE(acpi_ex_resolve_multiple);
348 
349 	/* Operand can be either a namespace node or an operand descriptor */
350 
351 	switch (ACPI_GET_DESCRIPTOR_TYPE(obj_desc)) {
352 	case ACPI_DESC_TYPE_OPERAND:
353 
354 		type = obj_desc->common.type;
355 		break;
356 
357 	case ACPI_DESC_TYPE_NAMED:
358 
359 		type = ((struct acpi_namespace_node *)obj_desc)->type;
360 		obj_desc = acpi_ns_get_attached_object(node);
361 
362 		/* If we had an Alias node, use the attached object for type info */
363 
364 		if (type == ACPI_TYPE_LOCAL_ALIAS) {
365 			type = ((struct acpi_namespace_node *)obj_desc)->type;
366 			obj_desc = acpi_ns_get_attached_object((struct
367 								acpi_namespace_node
368 								*)obj_desc);
369 		}
370 
371 		switch (type) {
372 		case ACPI_TYPE_DEVICE:
373 		case ACPI_TYPE_THERMAL:
374 
375 			/* These types have no attached subobject */
376 			break;
377 
378 		default:
379 
380 			/* All other types require a subobject */
381 
382 			if (!obj_desc) {
383 				ACPI_ERROR((AE_INFO,
384 					    "[%4.4s] Node is unresolved or uninitialized",
385 					    acpi_ut_get_node_name(node)));
386 				return_ACPI_STATUS(AE_AML_UNINITIALIZED_NODE);
387 			}
388 			break;
389 		}
390 		break;
391 
392 	default:
393 		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
394 	}
395 
396 	/* If type is anything other than a reference, we are done */
397 
398 	if (type != ACPI_TYPE_LOCAL_REFERENCE) {
399 		goto exit;
400 	}
401 
402 	/*
403 	 * For reference objects created via the ref_of, Index, or Load/load_table
404 	 * operators, we need to get to the base object (as per the ACPI
405 	 * specification of the object_type and size_of operators). This means
406 	 * traversing the list of possibly many nested references.
407 	 */
408 	while (obj_desc->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
409 		switch (obj_desc->reference.class) {
410 		case ACPI_REFCLASS_REFOF:
411 		case ACPI_REFCLASS_NAME:
412 
413 			/* Dereference the reference pointer */
414 
415 			if (obj_desc->reference.class == ACPI_REFCLASS_REFOF) {
416 				node = obj_desc->reference.object;
417 			} else {	/* AML_INT_NAMEPATH_OP */
418 
419 				node = obj_desc->reference.node;
420 			}
421 
422 			/* All "References" point to a NS node */
423 
424 			if (ACPI_GET_DESCRIPTOR_TYPE(node) !=
425 			    ACPI_DESC_TYPE_NAMED) {
426 				ACPI_ERROR((AE_INFO,
427 					    "Not a namespace node %p [%s]",
428 					    node,
429 					    acpi_ut_get_descriptor_name(node)));
430 				return_ACPI_STATUS(AE_AML_INTERNAL);
431 			}
432 
433 			/* Get the attached object */
434 
435 			obj_desc = acpi_ns_get_attached_object(node);
436 			if (!obj_desc) {
437 
438 				/* No object, use the NS node type */
439 
440 				type = acpi_ns_get_type(node);
441 				goto exit;
442 			}
443 
444 			/* Check for circular references */
445 
446 			if (obj_desc == operand) {
447 				return_ACPI_STATUS(AE_AML_CIRCULAR_REFERENCE);
448 			}
449 			break;
450 
451 		case ACPI_REFCLASS_INDEX:
452 
453 			/* Get the type of this reference (index into another object) */
454 
455 			type = obj_desc->reference.target_type;
456 			if (type != ACPI_TYPE_PACKAGE) {
457 				goto exit;
458 			}
459 
460 			/*
461 			 * The main object is a package, we want to get the type
462 			 * of the individual package element that is referenced by
463 			 * the index.
464 			 *
465 			 * This could of course in turn be another reference object.
466 			 */
467 			obj_desc = *(obj_desc->reference.where);
468 			if (!obj_desc) {
469 
470 				/* NULL package elements are allowed */
471 
472 				type = 0;	/* Uninitialized */
473 				goto exit;
474 			}
475 			break;
476 
477 		case ACPI_REFCLASS_TABLE:
478 
479 			type = ACPI_TYPE_DDB_HANDLE;
480 			goto exit;
481 
482 		case ACPI_REFCLASS_LOCAL:
483 		case ACPI_REFCLASS_ARG:
484 
485 			if (return_desc) {
486 				status =
487 				    acpi_ds_method_data_get_value(obj_desc->
488 								  reference.
489 								  class,
490 								  obj_desc->
491 								  reference.
492 								  value,
493 								  walk_state,
494 								  &obj_desc);
495 				if (ACPI_FAILURE(status)) {
496 					return_ACPI_STATUS(status);
497 				}
498 				acpi_ut_remove_reference(obj_desc);
499 			} else {
500 				status =
501 				    acpi_ds_method_data_get_node(obj_desc->
502 								 reference.
503 								 class,
504 								 obj_desc->
505 								 reference.
506 								 value,
507 								 walk_state,
508 								 &node);
509 				if (ACPI_FAILURE(status)) {
510 					return_ACPI_STATUS(status);
511 				}
512 
513 				obj_desc = acpi_ns_get_attached_object(node);
514 				if (!obj_desc) {
515 					type = ACPI_TYPE_ANY;
516 					goto exit;
517 				}
518 			}
519 			break;
520 
521 		case ACPI_REFCLASS_DEBUG:
522 
523 			/* The Debug Object is of type "DebugObject" */
524 
525 			type = ACPI_TYPE_DEBUG_OBJECT;
526 			goto exit;
527 
528 		default:
529 
530 			ACPI_ERROR((AE_INFO,
531 				    "Unknown Reference Class 0x%2.2X",
532 				    obj_desc->reference.class));
533 			return_ACPI_STATUS(AE_AML_INTERNAL);
534 		}
535 	}
536 
537 	/*
538 	 * Now we are guaranteed to have an object that has not been created
539 	 * via the ref_of or Index operators.
540 	 */
541 	type = obj_desc->common.type;
542 
543 exit:
544 	/* Convert internal types to external types */
545 
546 	switch (type) {
547 	case ACPI_TYPE_LOCAL_REGION_FIELD:
548 	case ACPI_TYPE_LOCAL_BANK_FIELD:
549 	case ACPI_TYPE_LOCAL_INDEX_FIELD:
550 
551 		type = ACPI_TYPE_FIELD_UNIT;
552 		break;
553 
554 	case ACPI_TYPE_LOCAL_SCOPE:
555 
556 		/* Per ACPI Specification, Scope is untyped */
557 
558 		type = ACPI_TYPE_ANY;
559 		break;
560 
561 	default:
562 
563 		/* No change to Type required */
564 
565 		break;
566 	}
567 
568 	*return_type = type;
569 	if (return_desc) {
570 		*return_desc = obj_desc;
571 	}
572 	return_ACPI_STATUS(AE_OK);
573 }
574