xref: /linux/drivers/acpi/acpica/dspkginit.c (revision e3b9f1e81de2083f359bacd2a94bf1c024f2ede0)
1 /******************************************************************************
2  *
3  * Module Name: dspkginit - Completion of deferred package initialization
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2018, 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 "acnamesp.h"
47 #include "amlcode.h"
48 #include "acdispat.h"
49 #include "acinterp.h"
50 
51 #define _COMPONENT          ACPI_NAMESPACE
52 ACPI_MODULE_NAME("dspkginit")
53 
54 /* Local prototypes */
55 static void
56 acpi_ds_resolve_package_element(union acpi_operand_object **element);
57 
58 /*******************************************************************************
59  *
60  * FUNCTION:    acpi_ds_build_internal_package_obj
61  *
62  * PARAMETERS:  walk_state      - Current walk state
63  *              op              - Parser object to be translated
64  *              element_count   - Number of elements in the package - this is
65  *                                the num_elements argument to Package()
66  *              obj_desc_ptr    - Where the ACPI internal object is returned
67  *
68  * RETURN:      Status
69  *
70  * DESCRIPTION: Translate a parser Op package object to the equivalent
71  *              namespace object
72  *
73  * NOTE: The number of elements in the package will be always be the num_elements
74  * count, regardless of the number of elements in the package list. If
75  * num_elements is smaller, only that many package list elements are used.
76  * if num_elements is larger, the Package object is padded out with
77  * objects of type Uninitialized (as per ACPI spec.)
78  *
79  * Even though the ASL compilers do not allow num_elements to be smaller
80  * than the Package list length (for the fixed length package opcode), some
81  * BIOS code modifies the AML on the fly to adjust the num_elements, and
82  * this code compensates for that. This also provides compatibility with
83  * other AML interpreters.
84  *
85  ******************************************************************************/
86 
87 acpi_status
88 acpi_ds_build_internal_package_obj(struct acpi_walk_state *walk_state,
89 				   union acpi_parse_object *op,
90 				   u32 element_count,
91 				   union acpi_operand_object **obj_desc_ptr)
92 {
93 	union acpi_parse_object *arg;
94 	union acpi_parse_object *parent;
95 	union acpi_operand_object *obj_desc = NULL;
96 	acpi_status status = AE_OK;
97 	u16 reference_count;
98 	u32 index;
99 	u32 i;
100 
101 	ACPI_FUNCTION_TRACE(ds_build_internal_package_obj);
102 
103 	/* Find the parent of a possibly nested package */
104 
105 	parent = op->common.parent;
106 	while ((parent->common.aml_opcode == AML_PACKAGE_OP) ||
107 	       (parent->common.aml_opcode == AML_VARIABLE_PACKAGE_OP)) {
108 		parent = parent->common.parent;
109 	}
110 
111 	/*
112 	 * If we are evaluating a Named package object of the form:
113 	 *      Name (xxxx, Package)
114 	 * the package object already exists, otherwise it must be created.
115 	 */
116 	obj_desc = *obj_desc_ptr;
117 	if (!obj_desc) {
118 		obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_PACKAGE);
119 		*obj_desc_ptr = obj_desc;
120 		if (!obj_desc) {
121 			return_ACPI_STATUS(AE_NO_MEMORY);
122 		}
123 
124 		obj_desc->package.node = parent->common.node;
125 	}
126 
127 	if (obj_desc->package.flags & AOPOBJ_DATA_VALID) {	/* Just in case */
128 		return_ACPI_STATUS(AE_OK);
129 	}
130 
131 	/*
132 	 * Allocate the element array (array of pointers to the individual
133 	 * objects) based on the num_elements parameter. Add an extra pointer slot
134 	 * so that the list is always null terminated.
135 	 */
136 	obj_desc->package.elements = ACPI_ALLOCATE_ZEROED(((acpi_size)
137 							   element_count +
138 							   1) * sizeof(void *));
139 
140 	if (!obj_desc->package.elements) {
141 		acpi_ut_delete_object_desc(obj_desc);
142 		return_ACPI_STATUS(AE_NO_MEMORY);
143 	}
144 
145 	obj_desc->package.count = element_count;
146 	arg = op->common.value.arg;
147 	arg = arg->common.next;
148 
149 	if (arg) {
150 		obj_desc->package.flags |= AOPOBJ_DATA_VALID;
151 	}
152 
153 	/*
154 	 * Initialize the elements of the package, up to the num_elements count.
155 	 * Package is automatically padded with uninitialized (NULL) elements
156 	 * if num_elements is greater than the package list length. Likewise,
157 	 * Package is truncated if num_elements is less than the list length.
158 	 */
159 	for (i = 0; arg && (i < element_count); i++) {
160 		if (arg->common.aml_opcode == AML_INT_RETURN_VALUE_OP) {
161 			if (arg->common.node->type == ACPI_TYPE_METHOD) {
162 				/*
163 				 * A method reference "looks" to the parser to be a method
164 				 * invocation, so we special case it here
165 				 */
166 				arg->common.aml_opcode = AML_INT_NAMEPATH_OP;
167 				status =
168 				    acpi_ds_build_internal_object(walk_state,
169 								  arg,
170 								  &obj_desc->
171 								  package.
172 								  elements[i]);
173 			} else {
174 				/* This package element is already built, just get it */
175 
176 				obj_desc->package.elements[i] =
177 				    ACPI_CAST_PTR(union acpi_operand_object,
178 						  arg->common.node);
179 			}
180 		} else {
181 			status =
182 			    acpi_ds_build_internal_object(walk_state, arg,
183 							  &obj_desc->package.
184 							  elements[i]);
185 			if (status == AE_NOT_FOUND) {
186 				ACPI_ERROR((AE_INFO, "%-48s",
187 					    "****DS namepath not found"));
188 			}
189 
190 			/*
191 			 * Initialize this package element. This function handles the
192 			 * resolution of named references within the package.
193 			 */
194 			acpi_ds_init_package_element(0,
195 						     obj_desc->package.
196 						     elements[i], NULL,
197 						     &obj_desc->package.
198 						     elements[i]);
199 		}
200 
201 		if (*obj_desc_ptr) {
202 
203 			/* Existing package, get existing reference count */
204 
205 			reference_count =
206 			    (*obj_desc_ptr)->common.reference_count;
207 			if (reference_count > 1) {
208 
209 				/* Make new element ref count match original ref count */
210 				/* TBD: Probably need an acpi_ut_add_references function */
211 
212 				for (index = 0;
213 				     index < ((u32)reference_count - 1);
214 				     index++) {
215 					acpi_ut_add_reference((obj_desc->
216 							       package.
217 							       elements[i]));
218 				}
219 			}
220 		}
221 
222 		arg = arg->common.next;
223 	}
224 
225 	/* Check for match between num_elements and actual length of package_list */
226 
227 	if (arg) {
228 		/*
229 		 * num_elements was exhausted, but there are remaining elements in
230 		 * the package_list. Truncate the package to num_elements.
231 		 *
232 		 * Note: technically, this is an error, from ACPI spec: "It is an
233 		 * error for NumElements to be less than the number of elements in
234 		 * the PackageList". However, we just print a message and no
235 		 * exception is returned. This provides compatibility with other
236 		 * ACPI implementations. Some firmware implementations will alter
237 		 * the num_elements on the fly, possibly creating this type of
238 		 * ill-formed package object.
239 		 */
240 		while (arg) {
241 			/*
242 			 * We must delete any package elements that were created earlier
243 			 * and are not going to be used because of the package truncation.
244 			 */
245 			if (arg->common.node) {
246 				acpi_ut_remove_reference(ACPI_CAST_PTR
247 							 (union
248 							  acpi_operand_object,
249 							  arg->common.node));
250 				arg->common.node = NULL;
251 			}
252 
253 			/* Find out how many elements there really are */
254 
255 			i++;
256 			arg = arg->common.next;
257 		}
258 
259 		ACPI_INFO(("Actual Package length (%u) is larger than "
260 			   "NumElements field (%u), truncated",
261 			   i, element_count));
262 	} else if (i < element_count) {
263 		/*
264 		 * Arg list (elements) was exhausted, but we did not reach
265 		 * num_elements count.
266 		 *
267 		 * Note: this is not an error, the package is padded out
268 		 * with NULLs.
269 		 */
270 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
271 				  "Package List length (%u) smaller than NumElements "
272 				  "count (%u), padded with null elements\n",
273 				  i, element_count));
274 	}
275 
276 	obj_desc->package.flags |= AOPOBJ_DATA_VALID;
277 	op->common.node = ACPI_CAST_PTR(struct acpi_namespace_node, obj_desc);
278 	return_ACPI_STATUS(status);
279 }
280 
281 /*******************************************************************************
282  *
283  * FUNCTION:    acpi_ds_init_package_element
284  *
285  * PARAMETERS:  acpi_pkg_callback
286  *
287  * RETURN:      Status
288  *
289  * DESCRIPTION: Resolve a named reference element within a package object
290  *
291  ******************************************************************************/
292 
293 acpi_status
294 acpi_ds_init_package_element(u8 object_type,
295 			     union acpi_operand_object *source_object,
296 			     union acpi_generic_state *state, void *context)
297 {
298 	union acpi_operand_object **element_ptr;
299 
300 	ACPI_FUNCTION_TRACE(ds_init_package_element);
301 
302 	if (!source_object) {
303 		return_ACPI_STATUS(AE_OK);
304 	}
305 
306 	/*
307 	 * The following code is a bit of a hack to workaround a (current)
308 	 * limitation of the acpi_pkg_callback interface. We need a pointer
309 	 * to the location within the element array because a new object
310 	 * may be created and stored there.
311 	 */
312 	if (context) {
313 
314 		/* A direct call was made to this function */
315 
316 		element_ptr = (union acpi_operand_object **)context;
317 	} else {
318 		/* Call came from acpi_ut_walk_package_tree */
319 
320 		element_ptr = state->pkg.this_target_obj;
321 	}
322 
323 	/* We are only interested in reference objects/elements */
324 
325 	if (source_object->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
326 
327 		/* Attempt to resolve the (named) reference to a namespace node */
328 
329 		acpi_ds_resolve_package_element(element_ptr);
330 	} else if (source_object->common.type == ACPI_TYPE_PACKAGE) {
331 		source_object->package.flags |= AOPOBJ_DATA_VALID;
332 	}
333 
334 	return_ACPI_STATUS(AE_OK);
335 }
336 
337 /*******************************************************************************
338  *
339  * FUNCTION:    acpi_ds_resolve_package_element
340  *
341  * PARAMETERS:  element_ptr         - Pointer to a reference object
342  *
343  * RETURN:      Possible new element is stored to the indirect element_ptr
344  *
345  * DESCRIPTION: Resolve a package element that is a reference to a named
346  *              object.
347  *
348  ******************************************************************************/
349 
350 static void
351 acpi_ds_resolve_package_element(union acpi_operand_object **element_ptr)
352 {
353 	acpi_status status;
354 	union acpi_generic_state scope_info;
355 	union acpi_operand_object *element = *element_ptr;
356 	struct acpi_namespace_node *resolved_node;
357 	struct acpi_namespace_node *original_node;
358 	char *external_path = NULL;
359 	acpi_object_type type;
360 
361 	ACPI_FUNCTION_TRACE(ds_resolve_package_element);
362 
363 	/* Check if reference element is already resolved */
364 
365 	if (element->reference.resolved) {
366 		return_VOID;
367 	}
368 
369 	/* Element must be a reference object of correct type */
370 
371 	scope_info.scope.node = element->reference.node;	/* Prefix node */
372 
373 	status = acpi_ns_lookup(&scope_info, (char *)element->reference.aml,	/* Pointer to AML path */
374 				ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
375 				ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE,
376 				NULL, &resolved_node);
377 	if (ACPI_FAILURE(status)) {
378 		status = acpi_ns_externalize_name(ACPI_UINT32_MAX,
379 						  (char *)element->reference.
380 						  aml, NULL, &external_path);
381 
382 		ACPI_EXCEPTION((AE_INFO, status,
383 				"Could not find/resolve named package element: %s",
384 				external_path));
385 
386 		ACPI_FREE(external_path);
387 		*element_ptr = NULL;
388 		return_VOID;
389 	} else if (resolved_node->type == ACPI_TYPE_ANY) {
390 
391 		/* Named reference not resolved, return a NULL package element */
392 
393 		ACPI_ERROR((AE_INFO,
394 			    "Could not resolve named package element [%4.4s] in [%4.4s]",
395 			    resolved_node->name.ascii,
396 			    scope_info.scope.node->name.ascii));
397 		*element_ptr = NULL;
398 		return_VOID;
399 	}
400 #if 0
401 	else if (resolved_node->flags & ANOBJ_TEMPORARY) {
402 		/*
403 		 * A temporary node found here indicates that the reference is
404 		 * to a node that was created within this method. We are not
405 		 * going to allow it (especially if the package is returned
406 		 * from the method) -- the temporary node will be deleted out
407 		 * from under the method. (05/2017).
408 		 */
409 		ACPI_ERROR((AE_INFO,
410 			    "Package element refers to a temporary name [%4.4s], "
411 			    "inserting a NULL element",
412 			    resolved_node->name.ascii));
413 		*element_ptr = NULL;
414 		return_VOID;
415 	}
416 #endif
417 
418 	/*
419 	 * Special handling for Alias objects. We need resolved_node to point
420 	 * to the Alias target. This effectively "resolves" the alias.
421 	 */
422 	if (resolved_node->type == ACPI_TYPE_LOCAL_ALIAS) {
423 		resolved_node = ACPI_CAST_PTR(struct acpi_namespace_node,
424 					      resolved_node->object);
425 	}
426 
427 	/* Update the reference object */
428 
429 	element->reference.resolved = TRUE;
430 	element->reference.node = resolved_node;
431 	type = element->reference.node->type;
432 
433 	/*
434 	 * Attempt to resolve the node to a value before we insert it into
435 	 * the package. If this is a reference to a common data type,
436 	 * resolve it immediately. According to the ACPI spec, package
437 	 * elements can only be "data objects" or method references.
438 	 * Attempt to resolve to an Integer, Buffer, String or Package.
439 	 * If cannot, return the named reference (for things like Devices,
440 	 * Methods, etc.) Buffer Fields and Fields will resolve to simple
441 	 * objects (int/buf/str/pkg).
442 	 *
443 	 * NOTE: References to things like Devices, Methods, Mutexes, etc.
444 	 * will remain as named references. This behavior is not described
445 	 * in the ACPI spec, but it appears to be an oversight.
446 	 */
447 	original_node = resolved_node;
448 	status = acpi_ex_resolve_node_to_value(&resolved_node, NULL);
449 	if (ACPI_FAILURE(status)) {
450 		return_VOID;
451 	}
452 #if 0
453 /* TBD - alias support */
454 	/*
455 	 * Special handling for Alias objects. We need to setup the type
456 	 * and the Op->Common.Node to point to the Alias target. Note,
457 	 * Alias has at most one level of indirection internally.
458 	 */
459 	type = op->common.node->type;
460 	if (type == ACPI_TYPE_LOCAL_ALIAS) {
461 		type = obj_desc->common.type;
462 		op->common.node = ACPI_CAST_PTR(struct acpi_namespace_node,
463 						op->common.node->object);
464 	}
465 #endif
466 
467 	switch (type) {
468 		/*
469 		 * These object types are a result of named references, so we will
470 		 * leave them as reference objects. In other words, these types
471 		 * have no intrinsic "value".
472 		 */
473 	case ACPI_TYPE_DEVICE:
474 	case ACPI_TYPE_THERMAL:
475 	case ACPI_TYPE_METHOD:
476 		break;
477 
478 	case ACPI_TYPE_MUTEX:
479 	case ACPI_TYPE_POWER:
480 	case ACPI_TYPE_PROCESSOR:
481 	case ACPI_TYPE_EVENT:
482 	case ACPI_TYPE_REGION:
483 
484 		/* acpi_ex_resolve_node_to_value gave these an extra reference */
485 
486 		acpi_ut_remove_reference(original_node->object);
487 		break;
488 
489 	default:
490 		/*
491 		 * For all other types - the node was resolved to an actual
492 		 * operand object with a value, return the object. Remove
493 		 * a reference on the existing object.
494 		 */
495 		acpi_ut_remove_reference(element);
496 		*element_ptr = (union acpi_operand_object *)resolved_node;
497 		break;
498 	}
499 
500 	return_VOID;
501 }
502