xref: /openbmc/linux/drivers/acpi/acpica/psutils.c (revision ee174d35)
1 /******************************************************************************
2  *
3  * Module Name: psutils - Parser miscellaneous utilities (Parser only)
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2017, 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 "amlcode.h"
48 #include "acconvert.h"
49 
50 #define _COMPONENT          ACPI_PARSER
51 ACPI_MODULE_NAME("psutils")
52 
53 /*******************************************************************************
54  *
55  * FUNCTION:    acpi_ps_create_scope_op
56  *
57  * PARAMETERS:  None
58  *
59  * RETURN:      A new Scope object, null on failure
60  *
61  * DESCRIPTION: Create a Scope and associated namepath op with the root name
62  *
63  ******************************************************************************/
64 union acpi_parse_object *acpi_ps_create_scope_op(u8 *aml)
65 {
66 	union acpi_parse_object *scope_op;
67 
68 	scope_op = acpi_ps_alloc_op(AML_SCOPE_OP, aml);
69 	if (!scope_op) {
70 		return (NULL);
71 	}
72 
73 	scope_op->named.name = ACPI_ROOT_NAME;
74 	return (scope_op);
75 }
76 
77 /*******************************************************************************
78  *
79  * FUNCTION:    acpi_ps_init_op
80  *
81  * PARAMETERS:  op              - A newly allocated Op object
82  *              opcode          - Opcode to store in the Op
83  *
84  * RETURN:      None
85  *
86  * DESCRIPTION: Initialize a parse (Op) object
87  *
88  ******************************************************************************/
89 
90 void acpi_ps_init_op(union acpi_parse_object *op, u16 opcode)
91 {
92 	ACPI_FUNCTION_ENTRY();
93 
94 	op->common.descriptor_type = ACPI_DESC_TYPE_PARSER;
95 	op->common.aml_opcode = opcode;
96 
97 	ACPI_DISASM_ONLY_MEMBERS(acpi_ut_safe_strncpy(op->common.aml_op_name,
98 						      (acpi_ps_get_opcode_info
99 						       (opcode))->name,
100 						      sizeof(op->common.
101 							     aml_op_name)));
102 }
103 
104 /*******************************************************************************
105  *
106  * FUNCTION:    acpi_ps_alloc_op
107  *
108  * PARAMETERS:  opcode          - Opcode that will be stored in the new Op
109  *              aml             - Address of the opcode
110  *
111  * RETURN:      Pointer to the new Op, null on failure
112  *
113  * DESCRIPTION: Allocate an acpi_op, choose op type (and thus size) based on
114  *              opcode. A cache of opcodes is available for the pure
115  *              GENERIC_OP, since this is by far the most commonly used.
116  *
117  ******************************************************************************/
118 
119 union acpi_parse_object *acpi_ps_alloc_op(u16 opcode, u8 *aml)
120 {
121 	union acpi_parse_object *op;
122 	const struct acpi_opcode_info *op_info;
123 	u8 flags = ACPI_PARSEOP_GENERIC;
124 
125 	ACPI_FUNCTION_ENTRY();
126 
127 	op_info = acpi_ps_get_opcode_info(opcode);
128 
129 	/* Determine type of parse_op required */
130 
131 	if (op_info->flags & AML_DEFER) {
132 		flags = ACPI_PARSEOP_DEFERRED;
133 	} else if (op_info->flags & AML_NAMED) {
134 		flags = ACPI_PARSEOP_NAMED_OBJECT;
135 	} else if (opcode == AML_INT_BYTELIST_OP) {
136 		flags = ACPI_PARSEOP_BYTELIST;
137 	}
138 
139 	/* Allocate the minimum required size object */
140 
141 	if (flags == ACPI_PARSEOP_GENERIC) {
142 
143 		/* The generic op (default) is by far the most common (16 to 1) */
144 
145 		op = acpi_os_acquire_object(acpi_gbl_ps_node_cache);
146 	} else {
147 		/* Extended parseop */
148 
149 		op = acpi_os_acquire_object(acpi_gbl_ps_node_ext_cache);
150 	}
151 
152 	/* Initialize the Op */
153 
154 	if (op) {
155 		acpi_ps_init_op(op, opcode);
156 		op->common.aml = aml;
157 		op->common.flags = flags;
158 		ASL_CV_CLEAR_OP_COMMENTS(op);
159 
160 		if (opcode == AML_SCOPE_OP) {
161 			acpi_gbl_current_scope = op;
162 		}
163 
164 		if (acpi_gbl_capture_comments) {
165 			ASL_CV_TRANSFER_COMMENTS(op);
166 		}
167 	}
168 
169 	return (op);
170 }
171 
172 /*******************************************************************************
173  *
174  * FUNCTION:    acpi_ps_free_op
175  *
176  * PARAMETERS:  op              - Op to be freed
177  *
178  * RETURN:      None.
179  *
180  * DESCRIPTION: Free an Op object. Either put it on the GENERIC_OP cache list
181  *              or actually free it.
182  *
183  ******************************************************************************/
184 
185 void acpi_ps_free_op(union acpi_parse_object *op)
186 {
187 	ACPI_FUNCTION_NAME(ps_free_op);
188 
189 	ASL_CV_CLEAR_OP_COMMENTS(op);
190 	if (op->common.aml_opcode == AML_INT_RETURN_VALUE_OP) {
191 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
192 				  "Free retval op: %p\n", op));
193 	}
194 
195 	if (op->common.flags & ACPI_PARSEOP_GENERIC) {
196 		(void)acpi_os_release_object(acpi_gbl_ps_node_cache, op);
197 	} else {
198 		(void)acpi_os_release_object(acpi_gbl_ps_node_ext_cache, op);
199 	}
200 }
201 
202 /*******************************************************************************
203  *
204  * FUNCTION:    Utility functions
205  *
206  * DESCRIPTION: Low level character and object functions
207  *
208  ******************************************************************************/
209 
210 /*
211  * Is "c" a namestring lead character?
212  */
213 u8 acpi_ps_is_leading_char(u32 c)
214 {
215 	return ((u8) (c == '_' || (c >= 'A' && c <= 'Z')));
216 }
217 
218 /*
219  * Get op's name (4-byte name segment) or 0 if unnamed
220  */
221 u32 acpi_ps_get_name(union acpi_parse_object * op)
222 {
223 
224 	/* The "generic" object has no name associated with it */
225 
226 	if (op->common.flags & ACPI_PARSEOP_GENERIC) {
227 		return (0);
228 	}
229 
230 	/* Only the "Extended" parse objects have a name */
231 
232 	return (op->named.name);
233 }
234 
235 /*
236  * Set op's name
237  */
238 void acpi_ps_set_name(union acpi_parse_object *op, u32 name)
239 {
240 
241 	/* The "generic" object has no name associated with it */
242 
243 	if (op->common.flags & ACPI_PARSEOP_GENERIC) {
244 		return;
245 	}
246 
247 	op->named.name = name;
248 }
249