xref: /openbmc/linux/drivers/acpi/acpica/psutils.c (revision da1d9caf)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: psutils - Parser miscellaneous utilities (Parser only)
5  *
6  * Copyright (C) 2000 - 2022, 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("psutils")
18 
19 /*******************************************************************************
20  *
21  * FUNCTION:    acpi_ps_create_scope_op
22  *
23  * PARAMETERS:  None
24  *
25  * RETURN:      A new Scope object, null on failure
26  *
27  * DESCRIPTION: Create a Scope and associated namepath op with the root name
28  *
29  ******************************************************************************/
30 union acpi_parse_object *acpi_ps_create_scope_op(u8 *aml)
31 {
32 	union acpi_parse_object *scope_op;
33 
34 	scope_op = acpi_ps_alloc_op(AML_SCOPE_OP, aml);
35 	if (!scope_op) {
36 		return (NULL);
37 	}
38 
39 	scope_op->named.name = ACPI_ROOT_NAME;
40 	return (scope_op);
41 }
42 
43 /*******************************************************************************
44  *
45  * FUNCTION:    acpi_ps_init_op
46  *
47  * PARAMETERS:  op              - A newly allocated Op object
48  *              opcode          - Opcode to store in the Op
49  *
50  * RETURN:      None
51  *
52  * DESCRIPTION: Initialize a parse (Op) object
53  *
54  ******************************************************************************/
55 
56 void acpi_ps_init_op(union acpi_parse_object *op, u16 opcode)
57 {
58 	ACPI_FUNCTION_ENTRY();
59 
60 	op->common.descriptor_type = ACPI_DESC_TYPE_PARSER;
61 	op->common.aml_opcode = opcode;
62 
63 	ACPI_DISASM_ONLY_MEMBERS(acpi_ut_safe_strncpy(op->common.aml_op_name,
64 						      (acpi_ps_get_opcode_info
65 						       (opcode))->name,
66 						      sizeof(op->common.
67 							     aml_op_name)));
68 }
69 
70 /*******************************************************************************
71  *
72  * FUNCTION:    acpi_ps_alloc_op
73  *
74  * PARAMETERS:  opcode          - Opcode that will be stored in the new Op
75  *              aml             - Address of the opcode
76  *
77  * RETURN:      Pointer to the new Op, null on failure
78  *
79  * DESCRIPTION: Allocate an acpi_op, choose op type (and thus size) based on
80  *              opcode. A cache of opcodes is available for the pure
81  *              GENERIC_OP, since this is by far the most commonly used.
82  *
83  ******************************************************************************/
84 
85 union acpi_parse_object *acpi_ps_alloc_op(u16 opcode, u8 *aml)
86 {
87 	union acpi_parse_object *op;
88 	const struct acpi_opcode_info *op_info;
89 	u8 flags = ACPI_PARSEOP_GENERIC;
90 
91 	ACPI_FUNCTION_ENTRY();
92 
93 	op_info = acpi_ps_get_opcode_info(opcode);
94 
95 	/* Determine type of parse_op required */
96 
97 	if (op_info->flags & AML_DEFER) {
98 		flags = ACPI_PARSEOP_DEFERRED;
99 	} else if (op_info->flags & AML_NAMED) {
100 		flags = ACPI_PARSEOP_NAMED_OBJECT;
101 	} else if (opcode == AML_INT_BYTELIST_OP) {
102 		flags = ACPI_PARSEOP_BYTELIST;
103 	}
104 
105 	/* Allocate the minimum required size object */
106 
107 	if (flags == ACPI_PARSEOP_GENERIC) {
108 
109 		/* The generic op (default) is by far the most common (16 to 1) */
110 
111 		op = acpi_os_acquire_object(acpi_gbl_ps_node_cache);
112 	} else {
113 		/* Extended parseop */
114 
115 		op = acpi_os_acquire_object(acpi_gbl_ps_node_ext_cache);
116 	}
117 
118 	/* Initialize the Op */
119 
120 	if (op) {
121 		acpi_ps_init_op(op, opcode);
122 		op->common.aml = aml;
123 		op->common.flags = flags;
124 		ASL_CV_CLEAR_OP_COMMENTS(op);
125 
126 		if (opcode == AML_SCOPE_OP) {
127 			acpi_gbl_current_scope = op;
128 		}
129 
130 		if (acpi_gbl_capture_comments) {
131 			ASL_CV_TRANSFER_COMMENTS(op);
132 		}
133 	}
134 
135 	return (op);
136 }
137 
138 /*******************************************************************************
139  *
140  * FUNCTION:    acpi_ps_free_op
141  *
142  * PARAMETERS:  op              - Op to be freed
143  *
144  * RETURN:      None.
145  *
146  * DESCRIPTION: Free an Op object. Either put it on the GENERIC_OP cache list
147  *              or actually free it.
148  *
149  ******************************************************************************/
150 
151 void acpi_ps_free_op(union acpi_parse_object *op)
152 {
153 	ACPI_FUNCTION_NAME(ps_free_op);
154 
155 	ASL_CV_CLEAR_OP_COMMENTS(op);
156 	if (op->common.aml_opcode == AML_INT_RETURN_VALUE_OP) {
157 		ACPI_DEBUG_PRINT((ACPI_DB_ALLOCATIONS,
158 				  "Free retval op: %p\n", op));
159 	}
160 
161 	if (op->common.flags & ACPI_PARSEOP_GENERIC) {
162 		(void)acpi_os_release_object(acpi_gbl_ps_node_cache, op);
163 	} else {
164 		(void)acpi_os_release_object(acpi_gbl_ps_node_ext_cache, op);
165 	}
166 }
167 
168 /*******************************************************************************
169  *
170  * FUNCTION:    Utility functions
171  *
172  * DESCRIPTION: Low level character and object functions
173  *
174  ******************************************************************************/
175 
176 /*
177  * Is "c" a namestring lead character?
178  */
179 u8 acpi_ps_is_leading_char(u32 c)
180 {
181 	return ((u8) (c == '_' || (c >= 'A' && c <= 'Z')));
182 }
183 
184 /*
185  * Get op's name (4-byte name segment) or 0 if unnamed
186  */
187 u32 acpi_ps_get_name(union acpi_parse_object * op)
188 {
189 
190 	/* The "generic" object has no name associated with it */
191 
192 	if (op->common.flags & ACPI_PARSEOP_GENERIC) {
193 		return (0);
194 	}
195 
196 	/* Only the "Extended" parse objects have a name */
197 
198 	return (op->named.name);
199 }
200 
201 /*
202  * Set op's name
203  */
204 void acpi_ps_set_name(union acpi_parse_object *op, u32 name)
205 {
206 
207 	/* The "generic" object has no name associated with it */
208 
209 	if (op->common.flags & ACPI_PARSEOP_GENERIC) {
210 		return;
211 	}
212 
213 	op->named.name = name;
214 }
215