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 - 2023, 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					      acpi_gbl_global_lock_mutex,
183					      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(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(current_value, base, &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((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((u64) swapped_id, 12);
315	out_string[4] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 8);
316	out_string[5] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 4);
317	out_string[6] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 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, 10);
347	out_string[digits_needed] = 0;
348
349	for (count = digits_needed; count > 0; count--) {
350		(void)acpi_ut_short_divide(value, 10, &value, &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((u64)class_code[0], 4);
379	out_string[1] = acpi_ut_hex_to_ascii_char((u64)class_code[0], 0);
380	out_string[2] = acpi_ut_hex_to_ascii_char((u64)class_code[1], 4);
381	out_string[3] = acpi_ut_hex_to_ascii_char((u64)class_code[1], 0);
382	out_string[4] = acpi_ut_hex_to_ascii_char((u64)class_code[2], 4);
383	out_string[5] = acpi_ut_hex_to_ascii_char((u64)class_code[2], 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