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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/acpi/acpica/
1/*******************************************************************************
2 *
3 * Module Name: nseval - Object evaluation, includes control method execution
4 *
5 ******************************************************************************/
6
7/*
8 * Copyright (C) 2000 - 2010, 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 "acparser.h"
47#include "acinterp.h"
48#include "acnamesp.h"
49
50#define _COMPONENT          ACPI_NAMESPACE
51ACPI_MODULE_NAME("nseval")
52
53/* Local prototypes */
54static void
55acpi_ns_exec_module_code(union acpi_operand_object *method_obj,
56			 struct acpi_evaluate_info *info);
57
58/*******************************************************************************
59 *
60 * FUNCTION:    acpi_ns_evaluate
61 *
62 * PARAMETERS:  Info            - Evaluation info block, contains:
63 *                  prefix_node     - Prefix or Method/Object Node to execute
64 *                  Pathname        - Name of method to execute, If NULL, the
65 *                                    Node is the object to execute
66 *                  Parameters      - List of parameters to pass to the method,
67 *                                    terminated by NULL. Params itself may be
68 *                                    NULL if no parameters are being passed.
69 *                  return_object   - Where to put method's return value (if
70 *                                    any). If NULL, no value is returned.
71 *                  parameter_type  - Type of Parameter list
72 *                  return_object   - Where to put method's return value (if
73 *                                    any). If NULL, no value is returned.
74 *                  Flags           - ACPI_IGNORE_RETURN_VALUE to delete return
75 *
76 * RETURN:      Status
77 *
78 * DESCRIPTION: Execute a control method or return the current value of an
79 *              ACPI namespace object.
80 *
81 * MUTEX:       Locks interpreter
82 *
83 ******************************************************************************/
84
85acpi_status acpi_ns_evaluate(struct acpi_evaluate_info * info)
86{
87	acpi_status status;
88	struct acpi_namespace_node *node;
89
90	ACPI_FUNCTION_TRACE(ns_evaluate);
91
92	if (!info) {
93		return_ACPI_STATUS(AE_BAD_PARAMETER);
94	}
95
96	/* Initialize the return value to an invalid object */
97
98	info->return_object = NULL;
99	info->param_count = 0;
100
101	/*
102	 * Get the actual namespace node for the target object. Handles these cases:
103	 *
104	 * 1) Null node, Pathname (absolute path)
105	 * 2) Node, Pathname (path relative to Node)
106	 * 3) Node, Null Pathname
107	 */
108	status = acpi_ns_get_node(info->prefix_node, info->pathname,
109				  ACPI_NS_NO_UPSEARCH, &info->resolved_node);
110	if (ACPI_FAILURE(status)) {
111		return_ACPI_STATUS(status);
112	}
113
114	/*
115	 * For a method alias, we must grab the actual method node so that proper
116	 * scoping context will be established before execution.
117	 */
118	if (acpi_ns_get_type(info->resolved_node) ==
119	    ACPI_TYPE_LOCAL_METHOD_ALIAS) {
120		info->resolved_node =
121		    ACPI_CAST_PTR(struct acpi_namespace_node,
122				  info->resolved_node->object);
123	}
124
125	ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "%s [%p] Value %p\n", info->pathname,
126			  info->resolved_node,
127			  acpi_ns_get_attached_object(info->resolved_node)));
128
129	node = info->resolved_node;
130
131	/*
132	 * Two major cases here:
133	 *
134	 * 1) The object is a control method -- execute it
135	 * 2) The object is not a method -- just return it's current value
136	 */
137	if (acpi_ns_get_type(info->resolved_node) == ACPI_TYPE_METHOD) {
138		/*
139		 * 1) Object is a control method - execute it
140		 */
141
142		/* Verify that there is a method object associated with this node */
143
144		info->obj_desc =
145		    acpi_ns_get_attached_object(info->resolved_node);
146		if (!info->obj_desc) {
147			ACPI_ERROR((AE_INFO,
148				    "Control method has no attached sub-object"));
149			return_ACPI_STATUS(AE_NULL_OBJECT);
150		}
151
152		/* Count the number of arguments being passed to the method */
153
154		if (info->parameters) {
155			while (info->parameters[info->param_count]) {
156				if (info->param_count > ACPI_METHOD_MAX_ARG) {
157					return_ACPI_STATUS(AE_LIMIT);
158				}
159				info->param_count++;
160			}
161		}
162
163
164		ACPI_DUMP_PATHNAME(info->resolved_node, "ACPI: Execute Method",
165				   ACPI_LV_INFO, _COMPONENT);
166
167		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
168				  "Method at AML address %p Length %X\n",
169				  info->obj_desc->method.aml_start + 1,
170				  info->obj_desc->method.aml_length - 1));
171
172		/*
173		 * Any namespace deletion must acquire both the namespace and
174		 * interpreter locks to ensure that no thread is using the portion of
175		 * the namespace that is being deleted.
176		 *
177		 * Execute the method via the interpreter. The interpreter is locked
178		 * here before calling into the AML parser
179		 */
180		acpi_ex_enter_interpreter();
181		status = acpi_ps_execute_method(info);
182		acpi_ex_exit_interpreter();
183	} else {
184		/*
185		 * 2) Object is not a method, return its current value
186		 *
187		 * Disallow certain object types. For these, "evaluation" is undefined.
188		 */
189		switch (info->resolved_node->type) {
190		case ACPI_TYPE_DEVICE:
191		case ACPI_TYPE_EVENT:
192		case ACPI_TYPE_MUTEX:
193		case ACPI_TYPE_REGION:
194		case ACPI_TYPE_THERMAL:
195		case ACPI_TYPE_LOCAL_SCOPE:
196
197			ACPI_ERROR((AE_INFO,
198				    "[%4.4s] Evaluation of object type [%s] is not supported",
199				    info->resolved_node->name.ascii,
200				    acpi_ut_get_type_name(info->resolved_node->
201							  type)));
202
203			return_ACPI_STATUS(AE_TYPE);
204
205		default:
206			break;
207		}
208
209		/*
210		 * Objects require additional resolution steps (e.g., the Node may be
211		 * a field that must be read, etc.) -- we can't just grab the object
212		 * out of the node.
213		 *
214		 * Use resolve_node_to_value() to get the associated value.
215		 *
216		 * NOTE: we can get away with passing in NULL for a walk state because
217		 * resolved_node is guaranteed to not be a reference to either a method
218		 * local or a method argument (because this interface is never called
219		 * from a running method.)
220		 *
221		 * Even though we do not directly invoke the interpreter for object
222		 * resolution, we must lock it because we could access an opregion.
223		 * The opregion access code assumes that the interpreter is locked.
224		 */
225		acpi_ex_enter_interpreter();
226
227		/* Function has a strange interface */
228
229		status =
230		    acpi_ex_resolve_node_to_value(&info->resolved_node, NULL);
231		acpi_ex_exit_interpreter();
232
233		/*
234		 * If acpi_ex_resolve_node_to_value() succeeded, the return value was placed
235		 * in resolved_node.
236		 */
237		if (ACPI_SUCCESS(status)) {
238			status = AE_CTRL_RETURN_VALUE;
239			info->return_object =
240			    ACPI_CAST_PTR(union acpi_operand_object,
241					  info->resolved_node);
242
243			ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
244					  "Returning object %p [%s]\n",
245					  info->return_object,
246					  acpi_ut_get_object_type_name(info->
247								       return_object)));
248		}
249	}
250
251	/*
252	 * Check input argument count against the ASL-defined count for a method.
253	 * Also check predefined names: argument count and return value against
254	 * the ACPI specification. Some incorrect return value types are repaired.
255	 */
256	(void)acpi_ns_check_predefined_names(node, info->param_count,
257		status, &info->return_object);
258
259	/* Check if there is a return value that must be dealt with */
260
261	if (status == AE_CTRL_RETURN_VALUE) {
262
263		/* If caller does not want the return value, delete it */
264
265		if (info->flags & ACPI_IGNORE_RETURN_VALUE) {
266			acpi_ut_remove_reference(info->return_object);
267			info->return_object = NULL;
268		}
269
270		/* Map AE_CTRL_RETURN_VALUE to AE_OK, we are done with it */
271
272		status = AE_OK;
273	}
274
275	ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
276			  "*** Completed evaluation of object %s ***\n",
277			  info->pathname));
278
279	/*
280	 * Namespace was unlocked by the handling acpi_ns* function, so we
281	 * just return
282	 */
283	return_ACPI_STATUS(status);
284}
285
286/*******************************************************************************
287 *
288 * FUNCTION:    acpi_ns_exec_module_code_list
289 *
290 * PARAMETERS:  None
291 *
292 * RETURN:      None. Exceptions during method execution are ignored, since
293 *              we cannot abort a table load.
294 *
295 * DESCRIPTION: Execute all elements of the global module-level code list.
296 *              Each element is executed as a single control method.
297 *
298 ******************************************************************************/
299
300void acpi_ns_exec_module_code_list(void)
301{
302	union acpi_operand_object *prev;
303	union acpi_operand_object *next;
304	struct acpi_evaluate_info *info;
305	u32 method_count = 0;
306
307	ACPI_FUNCTION_TRACE(ns_exec_module_code_list);
308
309	/* Exit now if the list is empty */
310
311	next = acpi_gbl_module_code_list;
312	if (!next) {
313		return_VOID;
314	}
315
316	/* Allocate the evaluation information block */
317
318	info = ACPI_ALLOCATE(sizeof(struct acpi_evaluate_info));
319	if (!info) {
320		return_VOID;
321	}
322
323	/* Walk the list, executing each "method" */
324
325	while (next) {
326		prev = next;
327		next = next->method.mutex;
328
329		/* Clear the link field and execute the method */
330
331		prev->method.mutex = NULL;
332		acpi_ns_exec_module_code(prev, info);
333		method_count++;
334
335		/* Delete the (temporary) method object */
336
337		acpi_ut_remove_reference(prev);
338	}
339
340	ACPI_INFO((AE_INFO,
341		   "Executed %u blocks of module-level executable AML code",
342		   method_count));
343
344	ACPI_FREE(info);
345	acpi_gbl_module_code_list = NULL;
346	return_VOID;
347}
348
349/*******************************************************************************
350 *
351 * FUNCTION:    acpi_ns_exec_module_code
352 *
353 * PARAMETERS:  method_obj          - Object container for the module-level code
354 *              Info                - Info block for method evaluation
355 *
356 * RETURN:      None. Exceptions during method execution are ignored, since
357 *              we cannot abort a table load.
358 *
359 * DESCRIPTION: Execute a control method containing a block of module-level
360 *              executable AML code. The control method is temporarily
361 *              installed to the root node, then evaluated.
362 *
363 ******************************************************************************/
364
365static void
366acpi_ns_exec_module_code(union acpi_operand_object *method_obj,
367			 struct acpi_evaluate_info *info)
368{
369	union acpi_operand_object *parent_obj;
370	struct acpi_namespace_node *parent_node;
371	acpi_object_type type;
372	acpi_status status;
373
374	ACPI_FUNCTION_TRACE(ns_exec_module_code);
375
376	/*
377	 * Get the parent node. We cheat by using the next_object field
378	 * of the method object descriptor.
379	 */
380	parent_node = ACPI_CAST_PTR(struct acpi_namespace_node,
381				    method_obj->method.next_object);
382	type = acpi_ns_get_type(parent_node);
383
384	/*
385	 * Get the region handler and save it in the method object. We may need
386	 * this if an operation region declaration causes a _REG method to be run.
387	 *
388	 * We can't do this in acpi_ps_link_module_code because
389	 * acpi_gbl_root_node->Object is NULL at PASS1.
390	 */
391	if ((type == ACPI_TYPE_DEVICE) && parent_node->object) {
392		method_obj->method.extra.handler =
393		    parent_node->object->device.handler;
394	}
395
396	/* Must clear next_object (acpi_ns_attach_object needs the field) */
397
398	method_obj->method.next_object = NULL;
399
400	/* Initialize the evaluation information block */
401
402	ACPI_MEMSET(info, 0, sizeof(struct acpi_evaluate_info));
403	info->prefix_node = parent_node;
404
405	/*
406	 * Get the currently attached parent object. Add a reference, because the
407	 * ref count will be decreased when the method object is installed to
408	 * the parent node.
409	 */
410	parent_obj = acpi_ns_get_attached_object(parent_node);
411	if (parent_obj) {
412		acpi_ut_add_reference(parent_obj);
413	}
414
415	/* Install the method (module-level code) in the parent node */
416
417	status = acpi_ns_attach_object(parent_node, method_obj,
418				       ACPI_TYPE_METHOD);
419	if (ACPI_FAILURE(status)) {
420		goto exit;
421	}
422
423	/* Execute the parent node as a control method */
424
425	status = acpi_ns_evaluate(info);
426
427	ACPI_DEBUG_PRINT((ACPI_DB_INIT, "Executed module-level code at %p\n",
428			  method_obj->method.aml_start));
429
430	/* Delete a possible implicit return value (in slack mode) */
431
432	if (info->return_object) {
433		acpi_ut_remove_reference(info->return_object);
434	}
435
436	/* Detach the temporary method object */
437
438	acpi_ns_detach_object(parent_node);
439
440	/* Restore the original parent object */
441
442	if (parent_obj) {
443		status = acpi_ns_attach_object(parent_node, parent_obj, type);
444	} else {
445		parent_node->type = (u8)type;
446	}
447
448      exit:
449	if (parent_obj) {
450		acpi_ut_remove_reference(parent_obj);
451	}
452	return_VOID;
453}
454