1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2/******************************************************************************
3 *
4 * Module Name: exresolv - AML Interpreter object resolution
5 *
6 * Copyright (C) 2000 - 2025, Intel Corp.
7 *
8 *****************************************************************************/
9
10#include <acpi/acpi.h>
11#include "accommon.h"
12#include "amlcode.h"
13#include "acdispat.h"
14#include "acinterp.h"
15#include "acnamesp.h"
16
17#define _COMPONENT ACPI_EXECUTER
18ACPI_MODULE_NAME("exresolv")
19
20/* Local prototypes */
21static acpi_status
22acpi_ex_resolve_object_to_value(union acpi_operand_object **stack_ptr,
23 struct acpi_walk_state *walk_state);
24
25/*******************************************************************************
26 *
27 * FUNCTION: acpi_ex_resolve_to_value
28 *
29 * PARAMETERS: **stack_ptr - Points to entry on obj_stack, which can
30 * be either an (union acpi_operand_object *)
31 * or an acpi_handle.
32 * walk_state - Current method state
33 *
34 * RETURN: Status
35 *
36 * DESCRIPTION: Convert Reference objects to values
37 *
38 ******************************************************************************/
39
40acpi_status
41acpi_ex_resolve_to_value(union acpi_operand_object **stack_ptr,
42 struct acpi_walk_state *walk_state)
43{
44 acpi_status status;
45
46 ACPI_FUNCTION_TRACE_PTR(ex_resolve_to_value, stack_ptr);
47
48 if (!stack_ptr || !*stack_ptr) {
49 ACPI_ERROR((AE_INFO, "Internal - null pointer"));
50 return_ACPI_STATUS(AE_AML_NO_OPERAND);
51 }
52
53 /*
54 * The entity pointed to by the stack_ptr can be either
55 * 1) A valid union acpi_operand_object, or
56 * 2) A struct acpi_namespace_node (named_obj)
57 */
58 if (ACPI_GET_DESCRIPTOR_TYPE(*stack_ptr) == ACPI_DESC_TYPE_OPERAND) {
59 status = acpi_ex_resolve_object_to_value(stack_ptr, walk_state);
60 if (ACPI_FAILURE(status)) {
61 return_ACPI_STATUS(status);
62 }
63
64 if (!*stack_ptr) {
65 ACPI_ERROR((AE_INFO, "Internal - null pointer"));
66 return_ACPI_STATUS(AE_AML_NO_OPERAND);
67 }
68 }
69
70 /*
71 * Object on the stack may have changed if acpi_ex_resolve_object_to_value()
72 * was called (i.e., we can't use an _else_ here.)
73 */
74 if (ACPI_GET_DESCRIPTOR_TYPE(*stack_ptr) == ACPI_DESC_TYPE_NAMED) {
75 status =
76 acpi_ex_resolve_node_to_value(ACPI_CAST_INDIRECT_PTR
77 (struct acpi_namespace_node,
78 stack_ptr), walk_state);
79 if (ACPI_FAILURE(status)) {
80 return_ACPI_STATUS(status);
81 }
82 }
83
84 ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Resolved object %p\n", *stack_ptr));
85 return_ACPI_STATUS(AE_OK);
86}
87
88/*******************************************************************************
89 *
90 * FUNCTION: acpi_ex_resolve_object_to_value
91 *
92 * PARAMETERS: stack_ptr - Pointer to an internal object
93 * walk_state - Current method state
94 *
95 * RETURN: Status
96 *
97 * DESCRIPTION: Retrieve the value from an internal object. The Reference type
98 * uses the associated AML opcode to determine the value.
99 *
100 ******************************************************************************/
101
102static acpi_status
103acpi_ex_resolve_object_to_value(union acpi_operand_object **stack_ptr,
104 struct acpi_walk_state *walk_state)
105{
106 acpi_status status = AE_OK;
107 union acpi_operand_object *stack_desc;
108 union acpi_operand_object *obj_desc = NULL;
109 u8 ref_type;
110
111 ACPI_FUNCTION_TRACE(ex_resolve_object_to_value);
112
113 stack_desc = *stack_ptr;
114
115 /* This is an object of type union acpi_operand_object */
116
117 switch (stack_desc->common.type) {
118 case ACPI_TYPE_LOCAL_REFERENCE:
119
120 ref_type = stack_desc->reference.class;
121
122 switch (ref_type) {
123 case ACPI_REFCLASS_LOCAL:
124 case ACPI_REFCLASS_ARG:
125 /*
126 * Get the local from the method's state info
127 * Note: this increments the local's object reference count
128 */
129 status = acpi_ds_method_data_get_value(type: ref_type,
130 index: stack_desc->
131 reference.value,
132 walk_state,
133 dest_desc: &obj_desc);
134 if (ACPI_FAILURE(status)) {
135 return_ACPI_STATUS(status);
136 }
137
138 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
139 "[Arg/Local %X] ValueObj is %p\n",
140 stack_desc->reference.value,
141 obj_desc));
142
143 /*
144 * Now we can delete the original Reference Object and
145 * replace it with the resolved value
146 */
147 acpi_ut_remove_reference(object: stack_desc);
148 *stack_ptr = obj_desc;
149 break;
150
151 case ACPI_REFCLASS_INDEX:
152
153 switch (stack_desc->reference.target_type) {
154 case ACPI_TYPE_BUFFER_FIELD:
155
156 /* Just return - do not dereference */
157 break;
158
159 case ACPI_TYPE_PACKAGE:
160
161 /* If method call or copy_object - do not dereference */
162
163 if ((walk_state->opcode ==
164 AML_INT_METHODCALL_OP)
165 || (walk_state->opcode ==
166 AML_COPY_OBJECT_OP)) {
167 break;
168 }
169
170 /* Otherwise, dereference the package_index to a package element */
171
172 obj_desc = *stack_desc->reference.where;
173 if (obj_desc) {
174 /*
175 * Valid object descriptor, copy pointer to return value
176 * (i.e., dereference the package index)
177 * Delete the ref object, increment the returned object
178 */
179 acpi_ut_add_reference(object: obj_desc);
180 *stack_ptr = obj_desc;
181 } else {
182 /*
183 * A NULL object descriptor means an uninitialized element of
184 * the package, can't dereference it
185 */
186 ACPI_ERROR((AE_INFO,
187 "Attempt to dereference an Index to "
188 "NULL package element Idx=%p",
189 stack_desc));
190 status = AE_AML_UNINITIALIZED_ELEMENT;
191 }
192 break;
193
194 default:
195
196 /* Invalid reference object */
197
198 ACPI_ERROR((AE_INFO,
199 "Unknown TargetType 0x%X in Index/Reference object %p",
200 stack_desc->reference.target_type,
201 stack_desc));
202 status = AE_AML_INTERNAL;
203 break;
204 }
205 break;
206
207 case ACPI_REFCLASS_REFOF:
208 case ACPI_REFCLASS_DEBUG:
209 case ACPI_REFCLASS_TABLE:
210
211 /* Just leave the object as-is, do not dereference */
212
213 break;
214
215 case ACPI_REFCLASS_NAME: /* Reference to a named object */
216
217 /* Dereference the name */
218
219 if ((stack_desc->reference.node->type ==
220 ACPI_TYPE_DEVICE)
221 || (stack_desc->reference.node->type ==
222 ACPI_TYPE_THERMAL)) {
223
224 /* These node types do not have 'real' subobjects */
225
226 *stack_ptr = (void *)stack_desc->reference.node;
227 } else {
228 /* Get the object pointed to by the namespace node */
229
230 *stack_ptr =
231 (stack_desc->reference.node)->object;
232 acpi_ut_add_reference(object: *stack_ptr);
233 }
234
235 acpi_ut_remove_reference(object: stack_desc);
236 break;
237
238 default:
239
240 ACPI_ERROR((AE_INFO,
241 "Unknown Reference type 0x%X in %p",
242 ref_type, stack_desc));
243 status = AE_AML_INTERNAL;
244 break;
245 }
246 break;
247
248 case ACPI_TYPE_BUFFER:
249
250 status = acpi_ds_get_buffer_arguments(obj_desc: stack_desc);
251 break;
252
253 case ACPI_TYPE_PACKAGE:
254
255 status = acpi_ds_get_package_arguments(obj_desc: stack_desc);
256 break;
257
258 case ACPI_TYPE_BUFFER_FIELD:
259 case ACPI_TYPE_LOCAL_REGION_FIELD:
260 case ACPI_TYPE_LOCAL_BANK_FIELD:
261 case ACPI_TYPE_LOCAL_INDEX_FIELD:
262
263 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
264 "FieldRead SourceDesc=%p Type=%X\n",
265 stack_desc, stack_desc->common.type));
266
267 status =
268 acpi_ex_read_data_from_field(walk_state, obj_desc: stack_desc,
269 ret_buffer_desc: &obj_desc);
270
271 /* Remove a reference to the original operand, then override */
272
273 acpi_ut_remove_reference(object: *stack_ptr);
274 *stack_ptr = (void *)obj_desc;
275 break;
276
277 default:
278
279 break;
280 }
281
282 return_ACPI_STATUS(status);
283}
284
285/*******************************************************************************
286 *
287 * FUNCTION: acpi_ex_resolve_multiple
288 *
289 * PARAMETERS: walk_state - Current state (contains AML opcode)
290 * operand - Starting point for resolution
291 * return_type - Where the object type is returned
292 * return_desc - Where the resolved object is returned
293 *
294 * RETURN: Status
295 *
296 * DESCRIPTION: Return the base object and type. Traverse a reference list if
297 * necessary to get to the base object.
298 *
299 ******************************************************************************/
300
301acpi_status
302acpi_ex_resolve_multiple(struct acpi_walk_state *walk_state,
303 union acpi_operand_object *operand,
304 acpi_object_type *return_type,
305 union acpi_operand_object **return_desc)
306{
307 union acpi_operand_object *obj_desc = ACPI_CAST_PTR(void, operand);
308 struct acpi_namespace_node *node =
309 ACPI_CAST_PTR(struct acpi_namespace_node, operand);
310 acpi_object_type type;
311 acpi_status status;
312
313 ACPI_FUNCTION_TRACE(acpi_ex_resolve_multiple);
314
315 /* Operand can be either a namespace node or an operand descriptor */
316
317 switch (ACPI_GET_DESCRIPTOR_TYPE(obj_desc)) {
318 case ACPI_DESC_TYPE_OPERAND:
319
320 type = obj_desc->common.type;
321 break;
322
323 case ACPI_DESC_TYPE_NAMED:
324
325 type = ((struct acpi_namespace_node *)obj_desc)->type;
326 obj_desc = acpi_ns_get_attached_object(node);
327
328 /* If we had an Alias node, use the attached object for type info */
329
330 if (type == ACPI_TYPE_LOCAL_ALIAS) {
331 type = ((struct acpi_namespace_node *)obj_desc)->type;
332 obj_desc = acpi_ns_get_attached_object(node: (struct
333 acpi_namespace_node
334 *)obj_desc);
335 }
336
337 switch (type) {
338 case ACPI_TYPE_DEVICE:
339 case ACPI_TYPE_THERMAL:
340
341 /* These types have no attached subobject */
342 break;
343
344 default:
345
346 /* All other types require a subobject */
347
348 if (!obj_desc) {
349 ACPI_ERROR((AE_INFO,
350 "[%4.4s] Node is unresolved or uninitialized",
351 acpi_ut_get_node_name(node)));
352 return_ACPI_STATUS(AE_AML_UNINITIALIZED_NODE);
353 }
354 break;
355 }
356 break;
357
358 default:
359 return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
360 }
361
362 /* If type is anything other than a reference, we are done */
363
364 if (type != ACPI_TYPE_LOCAL_REFERENCE) {
365 goto exit;
366 }
367
368 /*
369 * For reference objects created via the ref_of, Index, or Load/load_table
370 * operators, we need to get to the base object (as per the ACPI
371 * specification of the object_type and size_of operators). This means
372 * traversing the list of possibly many nested references.
373 */
374 while (obj_desc->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
375 switch (obj_desc->reference.class) {
376 case ACPI_REFCLASS_REFOF:
377 case ACPI_REFCLASS_NAME:
378
379 /* Dereference the reference pointer */
380
381 if (obj_desc->reference.class == ACPI_REFCLASS_REFOF) {
382 node = obj_desc->reference.object;
383 } else { /* AML_INT_NAMEPATH_OP */
384
385 node = obj_desc->reference.node;
386 }
387
388 /* All "References" point to a NS node */
389
390 if (ACPI_GET_DESCRIPTOR_TYPE(node) !=
391 ACPI_DESC_TYPE_NAMED) {
392 ACPI_ERROR((AE_INFO,
393 "Not a namespace node %p [%s]",
394 node,
395 acpi_ut_get_descriptor_name(node)));
396 return_ACPI_STATUS(AE_AML_INTERNAL);
397 }
398
399 /* Get the attached object */
400
401 obj_desc = acpi_ns_get_attached_object(node);
402 if (!obj_desc) {
403
404 /* No object, use the NS node type */
405
406 type = acpi_ns_get_type(node);
407 goto exit;
408 }
409
410 /* Check for circular references */
411
412 if (obj_desc == operand) {
413 return_ACPI_STATUS(AE_AML_CIRCULAR_REFERENCE);
414 }
415 break;
416
417 case ACPI_REFCLASS_INDEX:
418
419 /* Get the type of this reference (index into another object) */
420
421 type = obj_desc->reference.target_type;
422 if (type != ACPI_TYPE_PACKAGE) {
423 goto exit;
424 }
425
426 /*
427 * The main object is a package, we want to get the type
428 * of the individual package element that is referenced by
429 * the index.
430 *
431 * This could of course in turn be another reference object.
432 */
433 obj_desc = *(obj_desc->reference.where);
434 if (!obj_desc) {
435
436 /* NULL package elements are allowed */
437
438 type = 0; /* Uninitialized */
439 goto exit;
440 }
441 break;
442
443 case ACPI_REFCLASS_TABLE:
444
445 type = ACPI_TYPE_DDB_HANDLE;
446 goto exit;
447
448 case ACPI_REFCLASS_LOCAL:
449 case ACPI_REFCLASS_ARG:
450
451 if (return_desc) {
452 status =
453 acpi_ds_method_data_get_value(type: obj_desc->
454 reference.
455 class,
456 index: obj_desc->
457 reference.
458 value,
459 walk_state,
460 dest_desc: &obj_desc);
461 if (ACPI_FAILURE(status)) {
462 return_ACPI_STATUS(status);
463 }
464 acpi_ut_remove_reference(object: obj_desc);
465 } else {
466 status =
467 acpi_ds_method_data_get_node(type: obj_desc->
468 reference.
469 class,
470 index: obj_desc->
471 reference.
472 value,
473 walk_state,
474 node: &node);
475 if (ACPI_FAILURE(status)) {
476 return_ACPI_STATUS(status);
477 }
478
479 obj_desc = acpi_ns_get_attached_object(node);
480 if (!obj_desc) {
481 type = ACPI_TYPE_ANY;
482 goto exit;
483 }
484 }
485 break;
486
487 case ACPI_REFCLASS_DEBUG:
488
489 /* The Debug Object is of type "DebugObject" */
490
491 type = ACPI_TYPE_DEBUG_OBJECT;
492 goto exit;
493
494 default:
495
496 ACPI_ERROR((AE_INFO,
497 "Unknown Reference Class 0x%2.2X",
498 obj_desc->reference.class));
499 return_ACPI_STATUS(AE_AML_INTERNAL);
500 }
501 }
502
503 /*
504 * Now we are guaranteed to have an object that has not been created
505 * via the ref_of or Index operators.
506 */
507 type = obj_desc->common.type;
508
509exit:
510 /* Convert internal types to external types */
511
512 switch (type) {
513 case ACPI_TYPE_LOCAL_REGION_FIELD:
514 case ACPI_TYPE_LOCAL_BANK_FIELD:
515 case ACPI_TYPE_LOCAL_INDEX_FIELD:
516
517 type = ACPI_TYPE_FIELD_UNIT;
518 break;
519
520 case ACPI_TYPE_LOCAL_SCOPE:
521
522 /* Per ACPI Specification, Scope is untyped */
523
524 type = ACPI_TYPE_ANY;
525 break;
526
527 default:
528
529 /* No change to Type required */
530
531 break;
532 }
533
534 *return_type = type;
535 if (return_desc) {
536 *return_desc = obj_desc;
537 }
538 return_ACPI_STATUS(AE_OK);
539}
540