xref: /openbmc/linux/drivers/acpi/acpica/psutils.c (revision 4fa4616e)
1 /******************************************************************************
2  *
3  * Module Name: psutils - Parser miscellaneous utilities (Parser only)
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2015, 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 
49 #define _COMPONENT          ACPI_PARSER
50 ACPI_MODULE_NAME("psutils")
51 
52 /*******************************************************************************
53  *
54  * FUNCTION:    acpi_ps_create_scope_op
55  *
56  * PARAMETERS:  None
57  *
58  * RETURN:      A new Scope object, null on failure
59  *
60  * DESCRIPTION: Create a Scope and associated namepath op with the root name
61  *
62  ******************************************************************************/
63 union acpi_parse_object *acpi_ps_create_scope_op(void)
64 {
65 	union acpi_parse_object *scope_op;
66 
67 	scope_op = acpi_ps_alloc_op(AML_SCOPE_OP);
68 	if (!scope_op) {
69 		return (NULL);
70 	}
71 
72 	scope_op->named.name = ACPI_ROOT_NAME;
73 	return (scope_op);
74 }
75 
76 /*******************************************************************************
77  *
78  * FUNCTION:    acpi_ps_init_op
79  *
80  * PARAMETERS:  op              - A newly allocated Op object
81  *              opcode          - Opcode to store in the Op
82  *
83  * RETURN:      None
84  *
85  * DESCRIPTION: Initialize a parse (Op) object
86  *
87  ******************************************************************************/
88 
89 void acpi_ps_init_op(union acpi_parse_object *op, u16 opcode)
90 {
91 	ACPI_FUNCTION_ENTRY();
92 
93 	op->common.descriptor_type = ACPI_DESC_TYPE_PARSER;
94 	op->common.aml_opcode = opcode;
95 
96 	ACPI_DISASM_ONLY_MEMBERS(strncpy(op->common.aml_op_name,
97 					 (acpi_ps_get_opcode_info(opcode))->
98 					 name, sizeof(op->common.aml_op_name)));
99 }
100 
101 /*******************************************************************************
102  *
103  * FUNCTION:    acpi_ps_alloc_op
104  *
105  * PARAMETERS:  opcode          - Opcode that will be stored in the new Op
106  *
107  * RETURN:      Pointer to the new Op, null on failure
108  *
109  * DESCRIPTION: Allocate an acpi_op, choose op type (and thus size) based on
110  *              opcode. A cache of opcodes is available for the pure
111  *              GENERIC_OP, since this is by far the most commonly used.
112  *
113  ******************************************************************************/
114 
115 union acpi_parse_object *acpi_ps_alloc_op(u16 opcode)
116 {
117 	union acpi_parse_object *op;
118 	const struct acpi_opcode_info *op_info;
119 	u8 flags = ACPI_PARSEOP_GENERIC;
120 
121 	ACPI_FUNCTION_ENTRY();
122 
123 	op_info = acpi_ps_get_opcode_info(opcode);
124 
125 	/* Determine type of parse_op required */
126 
127 	if (op_info->flags & AML_DEFER) {
128 		flags = ACPI_PARSEOP_DEFERRED;
129 	} else if (op_info->flags & AML_NAMED) {
130 		flags = ACPI_PARSEOP_NAMED;
131 	} else if (opcode == AML_INT_BYTELIST_OP) {
132 		flags = ACPI_PARSEOP_BYTELIST;
133 	}
134 
135 	/* Allocate the minimum required size object */
136 
137 	if (flags == ACPI_PARSEOP_GENERIC) {
138 
139 		/* The generic op (default) is by far the most common (16 to 1) */
140 
141 		op = acpi_os_acquire_object(acpi_gbl_ps_node_cache);
142 	} else {
143 		/* Extended parseop */
144 
145 		op = acpi_os_acquire_object(acpi_gbl_ps_node_ext_cache);
146 	}
147 
148 	/* Initialize the Op */
149 
150 	if (op) {
151 		acpi_ps_init_op(op, opcode);
152 		op->common.flags = flags;
153 	}
154 
155 	return (op);
156 }
157 
158 /*******************************************************************************
159  *
160  * FUNCTION:    acpi_ps_free_op
161  *
162  * PARAMETERS:  op              - Op to be freed
163  *
164  * RETURN:      None.
165  *
166  * DESCRIPTION: Free an Op object. Either put it on the GENERIC_OP cache list
167  *              or actually free it.
168  *
169  ******************************************************************************/
170 
171 void acpi_ps_free_op(union acpi_parse_object *op)
172 {
173 	ACPI_FUNCTION_NAME(ps_free_op);
174 
175 	if (op->common.aml_opcode == AML_INT_RETURN_VALUE_OP) {
176 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS, "Free retval op: %p\n",
177 				  op));
178 	}
179 
180 	if (op->common.flags & ACPI_PARSEOP_GENERIC) {
181 		(void)acpi_os_release_object(acpi_gbl_ps_node_cache, op);
182 	} else {
183 		(void)acpi_os_release_object(acpi_gbl_ps_node_ext_cache, op);
184 	}
185 }
186 
187 /*******************************************************************************
188  *
189  * FUNCTION:    Utility functions
190  *
191  * DESCRIPTION: Low level character and object functions
192  *
193  ******************************************************************************/
194 
195 /*
196  * Is "c" a namestring lead character?
197  */
198 u8 acpi_ps_is_leading_char(u32 c)
199 {
200 	return ((u8) (c == '_' || (c >= 'A' && c <= 'Z')));
201 }
202 
203 /*
204  * Get op's name (4-byte name segment) or 0 if unnamed
205  */
206 #ifdef ACPI_FUTURE_USAGE
207 u32 acpi_ps_get_name(union acpi_parse_object * op)
208 {
209 
210 	/* The "generic" object has no name associated with it */
211 
212 	if (op->common.flags & ACPI_PARSEOP_GENERIC) {
213 		return (0);
214 	}
215 
216 	/* Only the "Extended" parse objects have a name */
217 
218 	return (op->named.name);
219 }
220 #endif				/*  ACPI_FUTURE_USAGE  */
221 
222 /*
223  * Set op's name
224  */
225 void acpi_ps_set_name(union acpi_parse_object *op, u32 name)
226 {
227 
228 	/* The "generic" object has no name associated with it */
229 
230 	if (op->common.flags & ACPI_PARSEOP_GENERIC) {
231 		return;
232 	}
233 
234 	op->named.name = name;
235 }
236