1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2/******************************************************************************
3 *
4 * Module Name: exutils - interpreter/scanner utilities
5 *
6 * Copyright (C) 2000 - 2025, Intel Corp.
7 *
8 *****************************************************************************/
9
10/*
11 * DEFINE_AML_GLOBALS is tested in amlcode.h
12 * to determine whether certain global names should be "defined" or only
13 * "declared" in the current compilation. This enhances maintainability
14 * by enabling a single header file to embody all knowledge of the names
15 * in question.
16 *
17 * Exactly one module of any executable should #define DEFINE_GLOBALS
18 * before #including the header files which use this convention. The
19 * names in question will be defined and initialized in that module,
20 * and declared as extern in all other modules which #include those
21 * header files.
22 */
23
24#define DEFINE_AML_GLOBALS
25
26#include <acpi/acpi.h>
27#include "accommon.h"
28#include "acinterp.h"
29#include "amlcode.h"
30
31#define _COMPONENT ACPI_EXECUTER
32ACPI_MODULE_NAME("exutils")
33
34/* Local prototypes */
35static u32 acpi_ex_digits_needed(u64 value, u32 base);
36
37/*******************************************************************************
38 *
39 * FUNCTION: acpi_ex_enter_interpreter
40 *
41 * PARAMETERS: None
42 *
43 * RETURN: None
44 *
45 * DESCRIPTION: Enter the interpreter execution region. Failure to enter
46 * the interpreter region is a fatal system error. Used in
47 * conjunction with exit_interpreter.
48 *
49 ******************************************************************************/
50
51void acpi_ex_enter_interpreter(void)
52{
53 acpi_status status;
54
55 ACPI_FUNCTION_TRACE(ex_enter_interpreter);
56
57 status = acpi_ut_acquire_mutex(ACPI_MTX_INTERPRETER);
58 if (ACPI_FAILURE(status)) {
59 ACPI_ERROR((AE_INFO,
60 "Could not acquire AML Interpreter mutex"));
61 }
62 status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
63 if (ACPI_FAILURE(status)) {
64 ACPI_ERROR((AE_INFO, "Could not acquire AML Namespace mutex"));
65 }
66
67 return_VOID;
68}
69
70/*******************************************************************************
71 *
72 * FUNCTION: acpi_ex_exit_interpreter
73 *
74 * PARAMETERS: None
75 *
76 * RETURN: None
77 *
78 * DESCRIPTION: Exit the interpreter execution region. This is the top level
79 * routine used to exit the interpreter when all processing has
80 * been completed, or when the method blocks.
81 *
82 * Cases where the interpreter is unlocked internally:
83 * 1) Method will be blocked on a Sleep() AML opcode
84 * 2) Method will be blocked on an Acquire() AML opcode
85 * 3) Method will be blocked on a Wait() AML opcode
86 * 4) Method will be blocked to acquire the global lock
87 * 5) Method will be blocked waiting to execute a serialized control
88 * method that is currently executing
89 * 6) About to invoke a user-installed opregion handler
90 *
91 ******************************************************************************/
92
93void acpi_ex_exit_interpreter(void)
94{
95 acpi_status status;
96
97 ACPI_FUNCTION_TRACE(ex_exit_interpreter);
98
99 status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
100 if (ACPI_FAILURE(status)) {
101 ACPI_ERROR((AE_INFO, "Could not release AML Namespace mutex"));
102 }
103 status = acpi_ut_release_mutex(ACPI_MTX_INTERPRETER);
104 if (ACPI_FAILURE(status)) {
105 ACPI_ERROR((AE_INFO,
106 "Could not release AML Interpreter mutex"));
107 }
108
109 return_VOID;
110}
111
112/*******************************************************************************
113 *
114 * FUNCTION: acpi_ex_truncate_for32bit_table
115 *
116 * PARAMETERS: obj_desc - Object to be truncated
117 *
118 * RETURN: TRUE if a truncation was performed, FALSE otherwise.
119 *
120 * DESCRIPTION: Truncate an ACPI Integer to 32 bits if the execution mode is
121 * 32-bit, as determined by the revision of the DSDT.
122 *
123 ******************************************************************************/
124
125u8 acpi_ex_truncate_for32bit_table(union acpi_operand_object *obj_desc)
126{
127
128 ACPI_FUNCTION_ENTRY();
129
130 /*
131 * Object must be a valid number and we must be executing
132 * a control method. Object could be NS node for AML_INT_NAMEPATH_OP.
133 */
134 if ((!obj_desc) ||
135 (ACPI_GET_DESCRIPTOR_TYPE(obj_desc) != ACPI_DESC_TYPE_OPERAND) ||
136 (obj_desc->common.type != ACPI_TYPE_INTEGER)) {
137 return (FALSE);
138 }
139
140 if ((acpi_gbl_integer_byte_width == 4) &&
141 (obj_desc->integer.value > (u64)ACPI_UINT32_MAX)) {
142 /*
143 * We are executing in a 32-bit ACPI table. Truncate
144 * the value to 32 bits by zeroing out the upper 32-bit field
145 */
146 obj_desc->integer.value &= (u64)ACPI_UINT32_MAX;
147 return (TRUE);
148 }
149
150 return (FALSE);
151}
152
153/*******************************************************************************
154 *
155 * FUNCTION: acpi_ex_acquire_global_lock
156 *
157 * PARAMETERS: field_flags - Flags with Lock rule:
158 * always_lock or never_lock
159 *
160 * RETURN: None
161 *
162 * DESCRIPTION: Obtain the ACPI hardware Global Lock, only if the field
163 * flags specify that it is to be obtained before field access.
164 *
165 ******************************************************************************/
166
167void acpi_ex_acquire_global_lock(u32 field_flags)
168{
169 acpi_status status;
170
171 ACPI_FUNCTION_TRACE(ex_acquire_global_lock);
172
173 /* Only use the lock if the always_lock bit is set */
174
175 if (!(field_flags & AML_FIELD_LOCK_RULE_MASK)) {
176 return_VOID;
177 }
178
179 /* Attempt to get the global lock, wait forever */
180
181 status = acpi_ex_acquire_mutex_object(ACPI_WAIT_FOREVER,
182 obj_desc: acpi_gbl_global_lock_mutex,
183 thread_id: acpi_os_get_thread_id());
184
185 if (ACPI_FAILURE(status)) {
186 ACPI_EXCEPTION((AE_INFO, status,
187 "Could not acquire Global Lock"));
188 }
189
190 return_VOID;
191}
192
193/*******************************************************************************
194 *
195 * FUNCTION: acpi_ex_release_global_lock
196 *
197 * PARAMETERS: field_flags - Flags with Lock rule:
198 * always_lock or never_lock
199 *
200 * RETURN: None
201 *
202 * DESCRIPTION: Release the ACPI hardware Global Lock
203 *
204 ******************************************************************************/
205
206void acpi_ex_release_global_lock(u32 field_flags)
207{
208 acpi_status status;
209
210 ACPI_FUNCTION_TRACE(ex_release_global_lock);
211
212 /* Only use the lock if the always_lock bit is set */
213
214 if (!(field_flags & AML_FIELD_LOCK_RULE_MASK)) {
215 return_VOID;
216 }
217
218 /* Release the global lock */
219
220 status = acpi_ex_release_mutex_object(obj_desc: acpi_gbl_global_lock_mutex);
221 if (ACPI_FAILURE(status)) {
222
223 /* Report the error, but there isn't much else we can do */
224
225 ACPI_EXCEPTION((AE_INFO, status,
226 "Could not release Global Lock"));
227 }
228
229 return_VOID;
230}
231
232/*******************************************************************************
233 *
234 * FUNCTION: acpi_ex_digits_needed
235 *
236 * PARAMETERS: value - Value to be represented
237 * base - Base of representation
238 *
239 * RETURN: The number of digits.
240 *
241 * DESCRIPTION: Calculate the number of digits needed to represent the Value
242 * in the given Base (Radix)
243 *
244 ******************************************************************************/
245
246static u32 acpi_ex_digits_needed(u64 value, u32 base)
247{
248 u32 num_digits;
249 u64 current_value;
250
251 ACPI_FUNCTION_TRACE(ex_digits_needed);
252
253 /* u64 is unsigned, so we don't worry about a '-' prefix */
254
255 if (value == 0) {
256 return_UINT32(1);
257 }
258
259 current_value = value;
260 num_digits = 0;
261
262 /* Count the digits in the requested base */
263
264 while (current_value) {
265 (void)acpi_ut_short_divide(in_dividend: current_value, divisor: base, out_quotient: &current_value,
266 NULL);
267 num_digits++;
268 }
269
270 return_UINT32(num_digits);
271}
272
273/*******************************************************************************
274 *
275 * FUNCTION: acpi_ex_eisa_id_to_string
276 *
277 * PARAMETERS: out_string - Where to put the converted string (8 bytes)
278 * compressed_id - EISAID to be converted
279 *
280 * RETURN: None
281 *
282 * DESCRIPTION: Convert a numeric EISAID to string representation. Return
283 * buffer must be large enough to hold the string. The string
284 * returned is always exactly of length ACPI_EISAID_STRING_SIZE
285 * (includes null terminator). The EISAID is always 32 bits.
286 *
287 ******************************************************************************/
288
289void acpi_ex_eisa_id_to_string(char *out_string, u64 compressed_id)
290{
291 u32 swapped_id;
292
293 ACPI_FUNCTION_ENTRY();
294
295 /* The EISAID should be a 32-bit integer */
296
297 if (compressed_id > ACPI_UINT32_MAX) {
298 ACPI_WARNING((AE_INFO,
299 "Expected EISAID is larger than 32 bits: "
300 "0x%8.8X%8.8X, truncating",
301 ACPI_FORMAT_UINT64(compressed_id)));
302 }
303
304 /* Swap ID to big-endian to get contiguous bits */
305
306 swapped_id = acpi_ut_dword_byte_swap(value: (u32)compressed_id);
307
308 /* First 3 bytes are uppercase letters. Next 4 bytes are hexadecimal */
309
310 out_string[0] =
311 (char)(0x40 + (((unsigned long)swapped_id >> 26) & 0x1F));
312 out_string[1] = (char)(0x40 + ((swapped_id >> 21) & 0x1F));
313 out_string[2] = (char)(0x40 + ((swapped_id >> 16) & 0x1F));
314 out_string[3] = acpi_ut_hex_to_ascii_char(integer: (u64) swapped_id, position: 12);
315 out_string[4] = acpi_ut_hex_to_ascii_char(integer: (u64) swapped_id, position: 8);
316 out_string[5] = acpi_ut_hex_to_ascii_char(integer: (u64) swapped_id, position: 4);
317 out_string[6] = acpi_ut_hex_to_ascii_char(integer: (u64) swapped_id, position: 0);
318 out_string[7] = 0;
319}
320
321/*******************************************************************************
322 *
323 * FUNCTION: acpi_ex_integer_to_string
324 *
325 * PARAMETERS: out_string - Where to put the converted string. At least
326 * 21 bytes are needed to hold the largest
327 * possible 64-bit integer.
328 * value - Value to be converted
329 *
330 * RETURN: Converted string in out_string
331 *
332 * DESCRIPTION: Convert a 64-bit integer to decimal string representation.
333 * Assumes string buffer is large enough to hold the string. The
334 * largest string is (ACPI_MAX64_DECIMAL_DIGITS + 1).
335 *
336 ******************************************************************************/
337
338void acpi_ex_integer_to_string(char *out_string, u64 value)
339{
340 u32 count;
341 u32 digits_needed;
342 u32 remainder;
343
344 ACPI_FUNCTION_ENTRY();
345
346 digits_needed = acpi_ex_digits_needed(value, base: 10);
347 out_string[digits_needed] = 0;
348
349 for (count = digits_needed; count > 0; count--) {
350 (void)acpi_ut_short_divide(in_dividend: value, divisor: 10, out_quotient: &value, out_remainder: &remainder);
351 out_string[count - 1] = (char)('0' + remainder);
352 }
353}
354
355/*******************************************************************************
356 *
357 * FUNCTION: acpi_ex_pci_cls_to_string
358 *
359 * PARAMETERS: out_string - Where to put the converted string (7 bytes)
360 * class_code - PCI class code to be converted (3 bytes)
361 *
362 * RETURN: Converted string in out_string
363 *
364 * DESCRIPTION: Convert 3-bytes PCI class code to string representation.
365 * Return buffer must be large enough to hold the string. The
366 * string returned is always exactly of length
367 * ACPI_PCICLS_STRING_SIZE (includes null terminator).
368 *
369 ******************************************************************************/
370
371void acpi_ex_pci_cls_to_string(char *out_string, u8 class_code[3])
372{
373
374 ACPI_FUNCTION_ENTRY();
375
376 /* All 3 bytes are hexadecimal */
377
378 out_string[0] = acpi_ut_hex_to_ascii_char(integer: (u64)class_code[0], position: 4);
379 out_string[1] = acpi_ut_hex_to_ascii_char(integer: (u64)class_code[0], position: 0);
380 out_string[2] = acpi_ut_hex_to_ascii_char(integer: (u64)class_code[1], position: 4);
381 out_string[3] = acpi_ut_hex_to_ascii_char(integer: (u64)class_code[1], position: 0);
382 out_string[4] = acpi_ut_hex_to_ascii_char(integer: (u64)class_code[2], position: 4);
383 out_string[5] = acpi_ut_hex_to_ascii_char(integer: (u64)class_code[2], position: 0);
384 out_string[6] = 0;
385}
386
387/*******************************************************************************
388 *
389 * FUNCTION: acpi_is_valid_space_id
390 *
391 * PARAMETERS: space_id - ID to be validated
392 *
393 * RETURN: TRUE if space_id is a valid/supported ID.
394 *
395 * DESCRIPTION: Validate an operation region space_ID.
396 *
397 ******************************************************************************/
398
399u8 acpi_is_valid_space_id(u8 space_id)
400{
401
402 if ((space_id >= ACPI_NUM_PREDEFINED_REGIONS) &&
403 (space_id < ACPI_USER_REGION_BEGIN) &&
404 (space_id != ACPI_ADR_SPACE_DATA_TABLE) &&
405 (space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) {
406 return (FALSE);
407 }
408
409 return (TRUE);
410}
411