1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3 *
4 * Module Name: dspkginit - Completion of deferred package initialization
5 *
6 * Copyright (C) 2000 - 2019, Intel Corp.
7 *
8 *****************************************************************************/
9
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acnamesp.h"
13 #include "amlcode.h"
14 #include "acdispat.h"
15 #include "acinterp.h"
16 #include "acparser.h"
17
18 #define _COMPONENT ACPI_NAMESPACE
19 ACPI_MODULE_NAME("dspkginit")
20
21 /* Local prototypes */
22 static void
23 acpi_ds_resolve_package_element(union acpi_operand_object **element);
24
25 /*******************************************************************************
26 *
27 * FUNCTION: acpi_ds_build_internal_package_obj
28 *
29 * PARAMETERS: walk_state - Current walk state
30 * op - Parser object to be translated
31 * element_count - Number of elements in the package - this is
32 * the num_elements argument to Package()
33 * obj_desc_ptr - Where the ACPI internal object is returned
34 *
35 * RETURN: Status
36 *
37 * DESCRIPTION: Translate a parser Op package object to the equivalent
38 * namespace object
39 *
40 * NOTE: The number of elements in the package will be always be the num_elements
41 * count, regardless of the number of elements in the package list. If
42 * num_elements is smaller, only that many package list elements are used.
43 * if num_elements is larger, the Package object is padded out with
44 * objects of type Uninitialized (as per ACPI spec.)
45 *
46 * Even though the ASL compilers do not allow num_elements to be smaller
47 * than the Package list length (for the fixed length package opcode), some
48 * BIOS code modifies the AML on the fly to adjust the num_elements, and
49 * this code compensates for that. This also provides compatibility with
50 * other AML interpreters.
51 *
52 ******************************************************************************/
53
54 acpi_status
55 acpi_ds_build_internal_package_obj(struct acpi_walk_state *walk_state,
56 union acpi_parse_object *op,
57 u32 element_count,
58 union acpi_operand_object **obj_desc_ptr)
59 {
60 union acpi_parse_object *arg;
61 union acpi_parse_object *parent;
62 union acpi_operand_object *obj_desc = NULL;
63 acpi_status status = AE_OK;
64 u8 module_level_code = FALSE;
65 u16 reference_count;
66 u32 index;
67 u32 i;
68
69 ACPI_FUNCTION_TRACE(ds_build_internal_package_obj);
70
71 /* Check if we are executing module level code */
72
73 if (walk_state->parse_flags & ACPI_PARSE_MODULE_LEVEL) {
74 module_level_code = TRUE;
75 }
76
77 /* Find the parent of a possibly nested package */
78
79 parent = op->common.parent;
80 while ((parent->common.aml_opcode == AML_PACKAGE_OP) ||
81 (parent->common.aml_opcode == AML_VARIABLE_PACKAGE_OP)) {
82 parent = parent->common.parent;
83 }
84
85 /*
86 * If we are evaluating a Named package object of the form:
87 * Name (xxxx, Package)
88 * the package object already exists, otherwise it must be created.
89 */
90 obj_desc = *obj_desc_ptr;
91 if (!obj_desc) {
92 obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_PACKAGE);
93 *obj_desc_ptr = obj_desc;
94 if (!obj_desc) {
95 return_ACPI_STATUS(AE_NO_MEMORY);
96 }
97
98 obj_desc->package.node = parent->common.node;
99 }
100
101 if (obj_desc->package.flags & AOPOBJ_DATA_VALID) { /* Just in case */
102 return_ACPI_STATUS(AE_OK);
103 }
104
105 /*
106 * Allocate the element array (array of pointers to the individual
107 * objects) if necessary. the count is based on the num_elements
108 * parameter. Add an extra pointer slot so that the list is always
109 * null terminated.
110 */
111 if (!obj_desc->package.elements) {
112 obj_desc->package.elements = ACPI_ALLOCATE_ZEROED(((acpi_size)
113 element_count
114 +
115 1) *
116 sizeof(void
117 *));
118
119 if (!obj_desc->package.elements) {
120 acpi_ut_delete_object_desc(obj_desc);
121 return_ACPI_STATUS(AE_NO_MEMORY);
122 }
123
124 obj_desc->package.count = element_count;
125 }
126
127 /* First arg is element count. Second arg begins the initializer list */
128
129 arg = op->common.value.arg;
130 arg = arg->common.next;
131
132 /*
133 * If we are executing module-level code, we will defer the
134 * full resolution of the package elements in order to support
135 * forward references from the elements. This provides
136 * compatibility with other ACPI implementations.
137 */
138 if (module_level_code) {
139 obj_desc->package.aml_start = walk_state->aml;
140 obj_desc->package.aml_length = 0;
141
142 ACPI_DEBUG_PRINT_RAW((ACPI_DB_PARSE,
143 "%s: Deferring resolution of Package elements\n",
144 ACPI_GET_FUNCTION_NAME));
145 }
146
147 /*
148 * Initialize the elements of the package, up to the num_elements count.
149 * Package is automatically padded with uninitialized (NULL) elements
150 * if num_elements is greater than the package list length. Likewise,
151 * Package is truncated if num_elements is less than the list length.
152 */
153 for (i = 0; arg && (i < element_count); i++) {
154 if (arg->common.aml_opcode == AML_INT_RETURN_VALUE_OP) {
155 if (!arg->common.node) {
156 /*
157 * This is the case where an expression has returned a value.
158 * The use of expressions (term_args) within individual
159 * package elements is not supported by the AML interpreter,
160 * even though the ASL grammar supports it. Example:
161 *
162 * Name (INT1, 0x1234)
163 *
164 * Name (PKG3, Package () {
165 * Add (INT1, 0xAAAA0000)
166 * })
167 *
168 * 1) No known AML interpreter supports this type of construct
169 * 2) This fixes a fault if the construct is encountered
170 */
171 ACPI_EXCEPTION((AE_INFO, AE_SUPPORT,
172 "Expressions within package elements are not supported"));
173
174 /* Cleanup the return object, it is not needed */
175
176 acpi_ut_remove_reference(walk_state->results->
177 results.obj_desc[0]);
178 return_ACPI_STATUS(AE_SUPPORT);
179 }
180
181 if (arg->common.node->type == ACPI_TYPE_METHOD) {
182 /*
183 * A method reference "looks" to the parser to be a method
184 * invocation, so we special case it here
185 */
186 arg->common.aml_opcode = AML_INT_NAMEPATH_OP;
187 status =
188 acpi_ds_build_internal_object(walk_state,
189 arg,
190 &obj_desc->
191 package.
192 elements[i]);
193 } else {
194 /* This package element is already built, just get it */
195
196 obj_desc->package.elements[i] =
197 ACPI_CAST_PTR(union acpi_operand_object,
198 arg->common.node);
199 }
200 } else {
201 status =
202 acpi_ds_build_internal_object(walk_state, arg,
203 &obj_desc->package.
204 elements[i]);
205 if (status == AE_NOT_FOUND) {
206 ACPI_ERROR((AE_INFO, "%-48s",
207 "****DS namepath not found"));
208 }
209
210 if (!module_level_code) {
211 /*
212 * Initialize this package element. This function handles the
213 * resolution of named references within the package.
214 * Forward references from module-level code are deferred
215 * until all ACPI tables are loaded.
216 */
217 acpi_ds_init_package_element(0,
218 obj_desc->package.
219 elements[i], NULL,
220 &obj_desc->package.
221 elements[i]);
222 }
223 }
224
225 if (*obj_desc_ptr) {
226
227 /* Existing package, get existing reference count */
228
229 reference_count =
230 (*obj_desc_ptr)->common.reference_count;
231 if (reference_count > 1) {
232
233 /* Make new element ref count match original ref count */
234 /* TBD: Probably need an acpi_ut_add_references function */
235
236 for (index = 0;
237 index < ((u32)reference_count - 1);
238 index++) {
239 acpi_ut_add_reference((obj_desc->
240 package.
241 elements[i]));
242 }
243 }
244 }
245
246 arg = arg->common.next;
247 }
248
249 /* Check for match between num_elements and actual length of package_list */
250
251 if (arg) {
252 /*
253 * num_elements was exhausted, but there are remaining elements in
254 * the package_list. Truncate the package to num_elements.
255 *
256 * Note: technically, this is an error, from ACPI spec: "It is an
257 * error for NumElements to be less than the number of elements in
258 * the PackageList". However, we just print a message and no
259 * exception is returned. This provides compatibility with other
260 * ACPI implementations. Some firmware implementations will alter
261 * the num_elements on the fly, possibly creating this type of
262 * ill-formed package object.
263 */
264 while (arg) {
265 /*
266 * We must delete any package elements that were created earlier
267 * and are not going to be used because of the package truncation.
268 */
269 if (arg->common.node) {
270 acpi_ut_remove_reference(ACPI_CAST_PTR
271 (union
272 acpi_operand_object,
273 arg->common.node));
274 arg->common.node = NULL;
275 }
276
277 /* Find out how many elements there really are */
278
279 i++;
280 arg = arg->common.next;
281 }
282
283 ACPI_INFO(("Actual Package length (%u) is larger than "
284 "NumElements field (%u), truncated",
285 i, element_count));
286 } else if (i < element_count) {
287 /*
288 * Arg list (elements) was exhausted, but we did not reach
289 * num_elements count.
290 *
291 * Note: this is not an error, the package is padded out
292 * with NULLs as per the ACPI specification.
293 */
294 ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO,
295 "%s: Package List length (%u) smaller than NumElements "
296 "count (%u), padded with null elements\n",
297 ACPI_GET_FUNCTION_NAME, i,
298 element_count));
299 }
300
301 /* Module-level packages will be resolved later */
302
303 if (!module_level_code) {
304 obj_desc->package.flags |= AOPOBJ_DATA_VALID;
305 }
306
307 op->common.node = ACPI_CAST_PTR(struct acpi_namespace_node, obj_desc);
308 return_ACPI_STATUS(status);
309 }
310
311 /*******************************************************************************
312 *
313 * FUNCTION: acpi_ds_init_package_element
314 *
315 * PARAMETERS: acpi_pkg_callback
316 *
317 * RETURN: Status
318 *
319 * DESCRIPTION: Resolve a named reference element within a package object
320 *
321 ******************************************************************************/
322
323 acpi_status
324 acpi_ds_init_package_element(u8 object_type,
325 union acpi_operand_object *source_object,
326 union acpi_generic_state *state, void *context)
327 {
328 union acpi_operand_object **element_ptr;
329
330 ACPI_FUNCTION_TRACE(ds_init_package_element);
331
332 if (!source_object) {
333 return_ACPI_STATUS(AE_OK);
334 }
335
336 /*
337 * The following code is a bit of a hack to workaround a (current)
338 * limitation of the acpi_pkg_callback interface. We need a pointer
339 * to the location within the element array because a new object
340 * may be created and stored there.
341 */
342 if (context) {
343
344 /* A direct call was made to this function */
345
346 element_ptr = (union acpi_operand_object **)context;
347 } else {
348 /* Call came from acpi_ut_walk_package_tree */
349
350 element_ptr = state->pkg.this_target_obj;
351 }
352
353 /* We are only interested in reference objects/elements */
354
355 if (source_object->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
356
357 /* Attempt to resolve the (named) reference to a namespace node */
358
359 acpi_ds_resolve_package_element(element_ptr);
360 } else if (source_object->common.type == ACPI_TYPE_PACKAGE) {
361 source_object->package.flags |= AOPOBJ_DATA_VALID;
362 }
363
364 return_ACPI_STATUS(AE_OK);
365 }
366
367 /*******************************************************************************
368 *
369 * FUNCTION: acpi_ds_resolve_package_element
370 *
371 * PARAMETERS: element_ptr - Pointer to a reference object
372 *
373 * RETURN: Possible new element is stored to the indirect element_ptr
374 *
375 * DESCRIPTION: Resolve a package element that is a reference to a named
376 * object.
377 *
378 ******************************************************************************/
379
380 static void
381 acpi_ds_resolve_package_element(union acpi_operand_object **element_ptr)
382 {
383 acpi_status status;
384 acpi_status status2;
385 union acpi_generic_state scope_info;
386 union acpi_operand_object *element = *element_ptr;
387 struct acpi_namespace_node *resolved_node;
388 struct acpi_namespace_node *original_node;
389 char *external_path = "";
390 acpi_object_type type;
391
392 ACPI_FUNCTION_TRACE(ds_resolve_package_element);
393
394 /* Check if reference element is already resolved */
395
396 if (element->reference.resolved) {
397 ACPI_DEBUG_PRINT_RAW((ACPI_DB_PARSE,
398 "%s: Package element is already resolved\n",
399 ACPI_GET_FUNCTION_NAME));
400
401 return_VOID;
402 }
403
404 /* Element must be a reference object of correct type */
405
406 scope_info.scope.node = element->reference.node; /* Prefix node */
407
408 status = acpi_ns_lookup(&scope_info, (char *)element->reference.aml,
409 ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
410 ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE,
411 NULL, &resolved_node);
412 if (ACPI_FAILURE(status)) {
413 if ((status == AE_NOT_FOUND)
414 && acpi_gbl_ignore_package_resolution_errors) {
415 /*
416 * Optionally be silent about the NOT_FOUND case for the referenced
417 * name. Although this is potentially a serious problem,
418 * it can generate a lot of noise/errors on platforms whose
419 * firmware carries around a bunch of unused Package objects.
420 * To disable these errors, set this global to TRUE:
421 * acpi_gbl_ignore_package_resolution_errors
422 *
423 * If the AML actually tries to use such a package, the unresolved
424 * element(s) will be replaced with NULL elements.
425 */
426
427 /* Referenced name not found, set the element to NULL */
428
429 acpi_ut_remove_reference(*element_ptr);
430 *element_ptr = NULL;
431 return_VOID;
432 }
433
434 status2 = acpi_ns_externalize_name(ACPI_UINT32_MAX,
435 (char *)element->reference.
436 aml, NULL, &external_path);
437
438 ACPI_EXCEPTION((AE_INFO, status,
439 "While resolving a named reference package element - %s",
440 external_path));
441 if (ACPI_SUCCESS(status2)) {
442 ACPI_FREE(external_path);
443 }
444
445 /* Could not resolve name, set the element to NULL */
446
447 acpi_ut_remove_reference(*element_ptr);
448 *element_ptr = NULL;
449 return_VOID;
450 } else if (resolved_node->type == ACPI_TYPE_ANY) {
451
452 /* Named reference not resolved, return a NULL package element */
453
454 ACPI_ERROR((AE_INFO,
455 "Could not resolve named package element [%4.4s] in [%4.4s]",
456 resolved_node->name.ascii,
457 scope_info.scope.node->name.ascii));
458 *element_ptr = NULL;
459 return_VOID;
460 }
461
462 /*
463 * Special handling for Alias objects. We need resolved_node to point
464 * to the Alias target. This effectively "resolves" the alias.
465 */
466 if (resolved_node->type == ACPI_TYPE_LOCAL_ALIAS) {
467 resolved_node = ACPI_CAST_PTR(struct acpi_namespace_node,
468 resolved_node->object);
469 }
470
471 /* Update the reference object */
472
473 element->reference.resolved = TRUE;
474 element->reference.node = resolved_node;
475 type = element->reference.node->type;
476
477 /*
478 * Attempt to resolve the node to a value before we insert it into
479 * the package. If this is a reference to a common data type,
480 * resolve it immediately. According to the ACPI spec, package
481 * elements can only be "data objects" or method references.
482 * Attempt to resolve to an Integer, Buffer, String or Package.
483 * If cannot, return the named reference (for things like Devices,
484 * Methods, etc.) Buffer Fields and Fields will resolve to simple
485 * objects (int/buf/str/pkg).
486 *
487 * NOTE: References to things like Devices, Methods, Mutexes, etc.
488 * will remain as named references. This behavior is not described
489 * in the ACPI spec, but it appears to be an oversight.
490 */
491 original_node = resolved_node;
492 status = acpi_ex_resolve_node_to_value(&resolved_node, NULL);
493 if (ACPI_FAILURE(status)) {
494 return_VOID;
495 }
496
497 switch (type) {
498 /*
499 * These object types are a result of named references, so we will
500 * leave them as reference objects. In other words, these types
501 * have no intrinsic "value".
502 */
503 case ACPI_TYPE_DEVICE:
504 case ACPI_TYPE_THERMAL:
505 case ACPI_TYPE_METHOD:
506 break;
507
508 case ACPI_TYPE_MUTEX:
509 case ACPI_TYPE_POWER:
510 case ACPI_TYPE_PROCESSOR:
511 case ACPI_TYPE_EVENT:
512 case ACPI_TYPE_REGION:
513
514 /* acpi_ex_resolve_node_to_value gave these an extra reference */
515
516 acpi_ut_remove_reference(original_node->object);
517 break;
518
519 default:
520 /*
521 * For all other types - the node was resolved to an actual
522 * operand object with a value, return the object. Remove
523 * a reference on the existing object.
524 */
525 acpi_ut_remove_reference(element);
526 *element_ptr = (union acpi_operand_object *)resolved_node;
527 break;
528 }
529
530 return_VOID;
531 }