xref: /openbmc/linux/drivers/acpi/acpica/psutils.c (revision 275876e2)
1 /******************************************************************************
2  *
3  * Module Name: psutils - Parser miscellaneous utilities (Parser only)
4  *
5  *****************************************************************************/
6 
7 /*
8  * Copyright (C) 2000 - 2014, 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(ACPI_STRNCPY(op->common.aml_op_name,
97 					      (acpi_ps_get_opcode_info
98 					       (opcode))->name,
99 					      sizeof(op->common.aml_op_name)));
100 }
101 
102 /*******************************************************************************
103  *
104  * FUNCTION:    acpi_ps_alloc_op
105  *
106  * PARAMETERS:  opcode          - Opcode that will be stored in the new Op
107  *
108  * RETURN:      Pointer to the new Op, null on failure
109  *
110  * DESCRIPTION: Allocate an acpi_op, choose op type (and thus size) based on
111  *              opcode. A cache of opcodes is available for the pure
112  *              GENERIC_OP, since this is by far the most commonly used.
113  *
114  ******************************************************************************/
115 
116 union acpi_parse_object *acpi_ps_alloc_op(u16 opcode)
117 {
118 	union acpi_parse_object *op;
119 	const struct acpi_opcode_info *op_info;
120 	u8 flags = ACPI_PARSEOP_GENERIC;
121 
122 	ACPI_FUNCTION_ENTRY();
123 
124 	op_info = acpi_ps_get_opcode_info(opcode);
125 
126 	/* Determine type of parse_op required */
127 
128 	if (op_info->flags & AML_DEFER) {
129 		flags = ACPI_PARSEOP_DEFERRED;
130 	} else if (op_info->flags & AML_NAMED) {
131 		flags = ACPI_PARSEOP_NAMED;
132 	} else if (opcode == AML_INT_BYTELIST_OP) {
133 		flags = ACPI_PARSEOP_BYTELIST;
134 	}
135 
136 	/* Allocate the minimum required size object */
137 
138 	if (flags == ACPI_PARSEOP_GENERIC) {
139 
140 		/* The generic op (default) is by far the most common (16 to 1) */
141 
142 		op = acpi_os_acquire_object(acpi_gbl_ps_node_cache);
143 	} else {
144 		/* Extended parseop */
145 
146 		op = acpi_os_acquire_object(acpi_gbl_ps_node_ext_cache);
147 	}
148 
149 	/* Initialize the Op */
150 
151 	if (op) {
152 		acpi_ps_init_op(op, opcode);
153 		op->common.flags = flags;
154 	}
155 
156 	return (op);
157 }
158 
159 /*******************************************************************************
160  *
161  * FUNCTION:    acpi_ps_free_op
162  *
163  * PARAMETERS:  op              - Op to be freed
164  *
165  * RETURN:      None.
166  *
167  * DESCRIPTION: Free an Op object. Either put it on the GENERIC_OP cache list
168  *              or actually free it.
169  *
170  ******************************************************************************/
171 
172 void acpi_ps_free_op(union acpi_parse_object *op)
173 {
174 	ACPI_FUNCTION_NAME(ps_free_op);
175 
176 	if (op->common.aml_opcode == AML_INT_RETURN_VALUE_OP) {
177 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS, "Free retval op: %p\n",
178 				  op));
179 	}
180 
181 	if (op->common.flags & ACPI_PARSEOP_GENERIC) {
182 		(void)acpi_os_release_object(acpi_gbl_ps_node_cache, op);
183 	} else {
184 		(void)acpi_os_release_object(acpi_gbl_ps_node_ext_cache, op);
185 	}
186 }
187 
188 /*******************************************************************************
189  *
190  * FUNCTION:    Utility functions
191  *
192  * DESCRIPTION: Low level character and object functions
193  *
194  ******************************************************************************/
195 
196 /*
197  * Is "c" a namestring lead character?
198  */
199 u8 acpi_ps_is_leading_char(u32 c)
200 {
201 	return ((u8) (c == '_' || (c >= 'A' && c <= 'Z')));
202 }
203 
204 /*
205  * Get op's name (4-byte name segment) or 0 if unnamed
206  */
207 #ifdef ACPI_FUTURE_USAGE
208 u32 acpi_ps_get_name(union acpi_parse_object * op)
209 {
210 
211 	/* The "generic" object has no name associated with it */
212 
213 	if (op->common.flags & ACPI_PARSEOP_GENERIC) {
214 		return (0);
215 	}
216 
217 	/* Only the "Extended" parse objects have a name */
218 
219 	return (op->named.name);
220 }
221 #endif				/*  ACPI_FUTURE_USAGE  */
222 
223 /*
224  * Set op's name
225  */
226 void acpi_ps_set_name(union acpi_parse_object *op, u32 name)
227 {
228 
229 	/* The "generic" object has no name associated with it */
230 
231 	if (op->common.flags & ACPI_PARSEOP_GENERIC) {
232 		return;
233 	}
234 
235 	op->named.name = name;
236 }
237