1  // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2  /******************************************************************************
3   *
4   * Module Name: exresnte - AML Interpreter object resolution
5   *
6   * Copyright (C) 2000 - 2023, Intel Corp.
7   *
8   *****************************************************************************/
9  
10  #include <acpi/acpi.h>
11  #include "accommon.h"
12  #include "acdispat.h"
13  #include "acinterp.h"
14  #include "acnamesp.h"
15  
16  #define _COMPONENT          ACPI_EXECUTER
17  ACPI_MODULE_NAME("exresnte")
18  
19  /*******************************************************************************
20   *
21   * FUNCTION:    acpi_ex_resolve_node_to_value
22   *
23   * PARAMETERS:  object_ptr      - Pointer to a location that contains
24   *                                a pointer to a NS node, and will receive a
25   *                                pointer to the resolved object.
26   *              walk_state      - Current state. Valid only if executing AML
27   *                                code. NULL if simply resolving an object
28   *
29   * RETURN:      Status
30   *
31   * DESCRIPTION: Resolve a Namespace node to a valued object
32   *
33   * Note: for some of the data types, the pointer attached to the Node
34   * can be either a pointer to an actual internal object or a pointer into the
35   * AML stream itself. These types are currently:
36   *
37   *      ACPI_TYPE_INTEGER
38   *      ACPI_TYPE_STRING
39   *      ACPI_TYPE_BUFFER
40   *      ACPI_TYPE_MUTEX
41   *      ACPI_TYPE_PACKAGE
42   *
43   ******************************************************************************/
44  acpi_status
acpi_ex_resolve_node_to_value(struct acpi_namespace_node ** object_ptr,struct acpi_walk_state * walk_state)45  acpi_ex_resolve_node_to_value(struct acpi_namespace_node **object_ptr,
46  			      struct acpi_walk_state *walk_state)
47  {
48  	acpi_status status = AE_OK;
49  	union acpi_operand_object *source_desc;
50  	union acpi_operand_object *obj_desc = NULL;
51  	struct acpi_namespace_node *node;
52  	acpi_object_type entry_type;
53  
54  	ACPI_FUNCTION_TRACE(ex_resolve_node_to_value);
55  
56  	/*
57  	 * The stack pointer points to a struct acpi_namespace_node (Node). Get the
58  	 * object that is attached to the Node.
59  	 */
60  	node = *object_ptr;
61  	source_desc = acpi_ns_get_attached_object(node);
62  	entry_type = acpi_ns_get_type((acpi_handle)node);
63  
64  	ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Entry=%p SourceDesc=%p [%s]\n",
65  			  node, source_desc,
66  			  acpi_ut_get_type_name(entry_type)));
67  
68  	if ((entry_type == ACPI_TYPE_LOCAL_ALIAS) ||
69  	    (entry_type == ACPI_TYPE_LOCAL_METHOD_ALIAS)) {
70  
71  		/* There is always exactly one level of indirection */
72  
73  		node = ACPI_CAST_PTR(struct acpi_namespace_node, node->object);
74  		source_desc = acpi_ns_get_attached_object(node);
75  		entry_type = acpi_ns_get_type((acpi_handle)node);
76  		*object_ptr = node;
77  	}
78  
79  	/*
80  	 * Several object types require no further processing:
81  	 * 1) Device/Thermal objects don't have a "real" subobject, return Node
82  	 * 2) Method locals and arguments have a pseudo-Node
83  	 * 3) 10/2007: Added method type to assist with Package construction.
84  	 */
85  	if ((entry_type == ACPI_TYPE_DEVICE) ||
86  	    (entry_type == ACPI_TYPE_THERMAL) ||
87  	    (entry_type == ACPI_TYPE_METHOD) ||
88  	    (node->flags & (ANOBJ_METHOD_ARG | ANOBJ_METHOD_LOCAL))) {
89  		return_ACPI_STATUS(AE_OK);
90  	}
91  
92  	if (!source_desc) {
93  		ACPI_ERROR((AE_INFO, "No object attached to node [%4.4s] %p",
94  			    node->name.ascii, node));
95  		return_ACPI_STATUS(AE_AML_UNINITIALIZED_NODE);
96  	}
97  
98  	/*
99  	 * Action is based on the type of the Node, which indicates the type
100  	 * of the attached object or pointer
101  	 */
102  	switch (entry_type) {
103  	case ACPI_TYPE_PACKAGE:
104  
105  		if (source_desc->common.type != ACPI_TYPE_PACKAGE) {
106  			ACPI_ERROR((AE_INFO, "Object not a Package, type %s",
107  				    acpi_ut_get_object_type_name(source_desc)));
108  			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
109  		}
110  
111  		status = acpi_ds_get_package_arguments(source_desc);
112  		if (ACPI_SUCCESS(status)) {
113  
114  			/* Return an additional reference to the object */
115  
116  			obj_desc = source_desc;
117  			acpi_ut_add_reference(obj_desc);
118  		}
119  		break;
120  
121  	case ACPI_TYPE_BUFFER:
122  
123  		if (source_desc->common.type != ACPI_TYPE_BUFFER) {
124  			ACPI_ERROR((AE_INFO, "Object not a Buffer, type %s",
125  				    acpi_ut_get_object_type_name(source_desc)));
126  			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
127  		}
128  
129  		status = acpi_ds_get_buffer_arguments(source_desc);
130  		if (ACPI_SUCCESS(status)) {
131  
132  			/* Return an additional reference to the object */
133  
134  			obj_desc = source_desc;
135  			acpi_ut_add_reference(obj_desc);
136  		}
137  		break;
138  
139  	case ACPI_TYPE_STRING:
140  
141  		if (source_desc->common.type != ACPI_TYPE_STRING) {
142  			ACPI_ERROR((AE_INFO, "Object not a String, type %s",
143  				    acpi_ut_get_object_type_name(source_desc)));
144  			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
145  		}
146  
147  		/* Return an additional reference to the object */
148  
149  		obj_desc = source_desc;
150  		acpi_ut_add_reference(obj_desc);
151  		break;
152  
153  	case ACPI_TYPE_INTEGER:
154  
155  		if (source_desc->common.type != ACPI_TYPE_INTEGER) {
156  			ACPI_ERROR((AE_INFO, "Object not a Integer, type %s",
157  				    acpi_ut_get_object_type_name(source_desc)));
158  			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
159  		}
160  
161  		/* Return an additional reference to the object */
162  
163  		obj_desc = source_desc;
164  		acpi_ut_add_reference(obj_desc);
165  		break;
166  
167  	case ACPI_TYPE_BUFFER_FIELD:
168  	case ACPI_TYPE_LOCAL_REGION_FIELD:
169  	case ACPI_TYPE_LOCAL_BANK_FIELD:
170  	case ACPI_TYPE_LOCAL_INDEX_FIELD:
171  
172  		ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
173  				  "FieldRead Node=%p SourceDesc=%p Type=%X\n",
174  				  node, source_desc, entry_type));
175  
176  		status =
177  		    acpi_ex_read_data_from_field(walk_state, source_desc,
178  						 &obj_desc);
179  		break;
180  
181  		/* For these objects, just return the object attached to the Node */
182  
183  	case ACPI_TYPE_MUTEX:
184  	case ACPI_TYPE_POWER:
185  	case ACPI_TYPE_PROCESSOR:
186  	case ACPI_TYPE_EVENT:
187  	case ACPI_TYPE_REGION:
188  
189  		/* Return an additional reference to the object */
190  
191  		obj_desc = source_desc;
192  		acpi_ut_add_reference(obj_desc);
193  		break;
194  
195  		/* TYPE_ANY is untyped, and thus there is no object associated with it */
196  
197  	case ACPI_TYPE_ANY:
198  
199  		ACPI_ERROR((AE_INFO,
200  			    "Untyped entry %p, no attached object!", node));
201  
202  		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);	/* Cannot be AE_TYPE */
203  
204  	case ACPI_TYPE_LOCAL_REFERENCE:
205  
206  		switch (source_desc->reference.class) {
207  		case ACPI_REFCLASS_TABLE:	/* This is a ddb_handle */
208  		case ACPI_REFCLASS_REFOF:
209  		case ACPI_REFCLASS_INDEX:
210  
211  			/* Return an additional reference to the object */
212  
213  			obj_desc = source_desc;
214  			acpi_ut_add_reference(obj_desc);
215  			break;
216  
217  		default:
218  
219  			/* No named references are allowed here */
220  
221  			ACPI_ERROR((AE_INFO,
222  				    "Unsupported Reference type 0x%X",
223  				    source_desc->reference.class));
224  
225  			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
226  		}
227  		break;
228  
229  	default:
230  
231  		/* Default case is for unknown types */
232  
233  		ACPI_ERROR((AE_INFO,
234  			    "Node %p - Unknown object type 0x%X",
235  			    node, entry_type));
236  
237  		return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
238  
239  	}			/* switch (entry_type) */
240  
241  	/* Return the object descriptor */
242  
243  	*object_ptr = (void *)obj_desc;
244  	return_ACPI_STATUS(status);
245  }
246