xref: /linux/drivers/acpi/acpica/pstree.c (revision 95298d63c67673c654c08952672d016212b26054)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: pstree - Parser op tree manipulation/traversal/search
5  *
6  * Copyright (C) 2000 - 2020, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acparser.h"
13 #include "amlcode.h"
14 #include "acconvert.h"
15 
16 #define _COMPONENT          ACPI_PARSER
17 ACPI_MODULE_NAME("pstree")
18 
19 /* Local prototypes */
20 #ifdef ACPI_OBSOLETE_FUNCTIONS
21 union acpi_parse_object *acpi_ps_get_child(union acpi_parse_object *op);
22 #endif
23 
24 /*******************************************************************************
25  *
26  * FUNCTION:    acpi_ps_get_arg
27  *
28  * PARAMETERS:  op              - Get an argument for this op
29  *              argn            - Nth argument to get
30  *
31  * RETURN:      The argument (as an Op object). NULL if argument does not exist
32  *
33  * DESCRIPTION: Get the specified op's argument.
34  *
35  ******************************************************************************/
36 
37 union acpi_parse_object *acpi_ps_get_arg(union acpi_parse_object *op, u32 argn)
38 {
39 	union acpi_parse_object *arg = NULL;
40 	const struct acpi_opcode_info *op_info;
41 
42 	ACPI_FUNCTION_ENTRY();
43 
44 /*
45 	if (Op->Common.aml_opcode == AML_INT_CONNECTION_OP)
46 	{
47 		return (Op->Common.Value.Arg);
48 	}
49 */
50 	/* Get the info structure for this opcode */
51 
52 	op_info = acpi_ps_get_opcode_info(op->common.aml_opcode);
53 	if (op_info->class == AML_CLASS_UNKNOWN) {
54 
55 		/* Invalid opcode or ASCII character */
56 
57 		return (NULL);
58 	}
59 
60 	/* Check if this opcode requires argument sub-objects */
61 
62 	if (!(op_info->flags & AML_HAS_ARGS)) {
63 
64 		/* Has no linked argument objects */
65 
66 		return (NULL);
67 	}
68 
69 	/* Get the requested argument object */
70 
71 	arg = op->common.value.arg;
72 	while (arg && argn) {
73 		argn--;
74 		arg = arg->common.next;
75 	}
76 
77 	return (arg);
78 }
79 
80 /*******************************************************************************
81  *
82  * FUNCTION:    acpi_ps_append_arg
83  *
84  * PARAMETERS:  op              - Append an argument to this Op.
85  *              arg             - Argument Op to append
86  *
87  * RETURN:      None.
88  *
89  * DESCRIPTION: Append an argument to an op's argument list (a NULL arg is OK)
90  *
91  ******************************************************************************/
92 
93 void
94 acpi_ps_append_arg(union acpi_parse_object *op, union acpi_parse_object *arg)
95 {
96 	union acpi_parse_object *prev_arg;
97 	const struct acpi_opcode_info *op_info;
98 
99 	ACPI_FUNCTION_TRACE(ps_append_arg);
100 
101 	if (!op) {
102 		return_VOID;
103 	}
104 
105 	/* Get the info structure for this opcode */
106 
107 	op_info = acpi_ps_get_opcode_info(op->common.aml_opcode);
108 	if (op_info->class == AML_CLASS_UNKNOWN) {
109 
110 		/* Invalid opcode */
111 
112 		ACPI_ERROR((AE_INFO, "Invalid AML Opcode: 0x%2.2X",
113 			    op->common.aml_opcode));
114 		return_VOID;
115 	}
116 
117 	/* Check if this opcode requires argument sub-objects */
118 
119 	if (!(op_info->flags & AML_HAS_ARGS)) {
120 
121 		/* Has no linked argument objects */
122 
123 		return_VOID;
124 	}
125 
126 	/* Append the argument to the linked argument list */
127 
128 	if (op->common.value.arg) {
129 
130 		/* Append to existing argument list */
131 
132 		prev_arg = op->common.value.arg;
133 		while (prev_arg->common.next) {
134 			prev_arg = prev_arg->common.next;
135 		}
136 		prev_arg->common.next = arg;
137 	} else {
138 		/* No argument list, this will be the first argument */
139 
140 		op->common.value.arg = arg;
141 	}
142 
143 	/* Set the parent in this arg and any args linked after it */
144 
145 	while (arg) {
146 		arg->common.parent = op;
147 		arg = arg->common.next;
148 
149 		op->common.arg_list_length++;
150 	}
151 
152 	return_VOID;
153 }
154 
155 /*******************************************************************************
156  *
157  * FUNCTION:    acpi_ps_get_depth_next
158  *
159  * PARAMETERS:  origin          - Root of subtree to search
160  *              op              - Last (previous) Op that was found
161  *
162  * RETURN:      Next Op found in the search.
163  *
164  * DESCRIPTION: Get next op in tree (walking the tree in depth-first order)
165  *              Return NULL when reaching "origin" or when walking up from root
166  *
167  ******************************************************************************/
168 
169 union acpi_parse_object *acpi_ps_get_depth_next(union acpi_parse_object *origin,
170 						union acpi_parse_object *op)
171 {
172 	union acpi_parse_object *next = NULL;
173 	union acpi_parse_object *parent;
174 	union acpi_parse_object *arg;
175 
176 	ACPI_FUNCTION_ENTRY();
177 
178 	if (!op) {
179 		return (NULL);
180 	}
181 
182 	/* Look for an argument or child */
183 
184 	next = acpi_ps_get_arg(op, 0);
185 	if (next) {
186 		ASL_CV_LABEL_FILENODE(next);
187 		return (next);
188 	}
189 
190 	/* Look for a sibling */
191 
192 	next = op->common.next;
193 	if (next) {
194 		ASL_CV_LABEL_FILENODE(next);
195 		return (next);
196 	}
197 
198 	/* Look for a sibling of parent */
199 
200 	parent = op->common.parent;
201 
202 	while (parent) {
203 		arg = acpi_ps_get_arg(parent, 0);
204 		while (arg && (arg != origin) && (arg != op)) {
205 
206 			ASL_CV_LABEL_FILENODE(arg);
207 			arg = arg->common.next;
208 		}
209 
210 		if (arg == origin) {
211 
212 			/* Reached parent of origin, end search */
213 
214 			return (NULL);
215 		}
216 
217 		if (parent->common.next) {
218 
219 			/* Found sibling of parent */
220 
221 			ASL_CV_LABEL_FILENODE(parent->common.next);
222 			return (parent->common.next);
223 		}
224 
225 		op = parent;
226 		parent = parent->common.parent;
227 	}
228 
229 	ASL_CV_LABEL_FILENODE(next);
230 	return (next);
231 }
232 
233 #ifdef ACPI_OBSOLETE_FUNCTIONS
234 /*******************************************************************************
235  *
236  * FUNCTION:    acpi_ps_get_child
237  *
238  * PARAMETERS:  op              - Get the child of this Op
239  *
240  * RETURN:      Child Op, Null if none is found.
241  *
242  * DESCRIPTION: Get op's children or NULL if none
243  *
244  ******************************************************************************/
245 
246 union acpi_parse_object *acpi_ps_get_child(union acpi_parse_object *op)
247 {
248 	union acpi_parse_object *child = NULL;
249 
250 	ACPI_FUNCTION_ENTRY();
251 
252 	switch (op->common.aml_opcode) {
253 	case AML_SCOPE_OP:
254 	case AML_ELSE_OP:
255 	case AML_DEVICE_OP:
256 	case AML_THERMAL_ZONE_OP:
257 	case AML_INT_METHODCALL_OP:
258 
259 		child = acpi_ps_get_arg(op, 0);
260 		break;
261 
262 	case AML_BUFFER_OP:
263 	case AML_PACKAGE_OP:
264 	case AML_VARIABLE_PACKAGE_OP:
265 	case AML_METHOD_OP:
266 	case AML_IF_OP:
267 	case AML_WHILE_OP:
268 	case AML_FIELD_OP:
269 
270 		child = acpi_ps_get_arg(op, 1);
271 		break;
272 
273 	case AML_POWER_RESOURCE_OP:
274 	case AML_INDEX_FIELD_OP:
275 
276 		child = acpi_ps_get_arg(op, 2);
277 		break;
278 
279 	case AML_PROCESSOR_OP:
280 	case AML_BANK_FIELD_OP:
281 
282 		child = acpi_ps_get_arg(op, 3);
283 		break;
284 
285 	default:
286 
287 		/* All others have no children */
288 
289 		break;
290 	}
291 
292 	return (child);
293 }
294 #endif
295