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2 /******************************************************************************
4 * Module Name: exutils - interpreter/scanner utilities
6 *****************************************************************************/
8 /*
9 * Copyright (C) 2000 - 2012, Intel Corp.
10 * All rights reserved.
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions, and the following disclaimer,
17 * without modification.
18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19 * substantially similar to the "NO WARRANTY" disclaimer below
20 * ("Disclaimer") and any redistribution must be conditioned upon
21 * including a substantially similar Disclaimer requirement for further
22 * binary redistribution.
23 * 3. Neither the names of the above-listed copyright holders nor the names
24 * of any contributors may be used to endorse or promote products derived
25 * from this software without specific prior written permission.
27 * Alternatively, this software may be distributed under the terms of the
28 * GNU General Public License ("GPL") version 2 as published by the Free
29 * Software Foundation.
31 * NO WARRANTY
32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42 * POSSIBILITY OF SUCH DAMAGES.
46 * DEFINE_AML_GLOBALS is tested in amlcode.h
47 * to determine whether certain global names should be "defined" or only
48 * "declared" in the current compilation. This enhances maintainability
49 * by enabling a single header file to embody all knowledge of the names
50 * in question.
52 * Exactly one module of any executable should #define DEFINE_GLOBALS
53 * before #including the header files which use this convention. The
54 * names in question will be defined and initialized in that module,
55 * and declared as extern in all other modules which #include those
56 * header files.
59 #define DEFINE_AML_GLOBALS
61 #include <acpi/acpi.h>
62 #include "accommon.h"
63 #include "acinterp.h"
64 #include "amlcode.h"
66 #define _COMPONENT ACPI_EXECUTER
67 ACPI_MODULE_NAME("exutils")
69 /* Local prototypes */
70 static u32 acpi_ex_digits_needed(u64 value, u32 base);
72 #ifndef ACPI_NO_METHOD_EXECUTION
73 /*******************************************************************************
75 * FUNCTION: acpi_ex_enter_interpreter
77 * PARAMETERS: None
79 * RETURN: None
81 * DESCRIPTION: Enter the interpreter execution region. Failure to enter
82 * the interpreter region is a fatal system error. Used in
83 * conjunction with exit_interpreter.
85 ******************************************************************************/
87 void acpi_ex_enter_interpreter(void)
89 acpi_status status;
91 ACPI_FUNCTION_TRACE(ex_enter_interpreter);
93 status = acpi_ut_acquire_mutex(ACPI_MTX_INTERPRETER);
94 if (ACPI_FAILURE(status)) {
95 ACPI_ERROR((AE_INFO,
96 "Could not acquire AML Interpreter mutex"));
99 return_VOID;
102 /*******************************************************************************
104 * FUNCTION: acpi_ex_reacquire_interpreter
106 * PARAMETERS: None
108 * RETURN: None
110 * DESCRIPTION: Reacquire the interpreter execution region from within the
111 * interpreter code. Failure to enter the interpreter region is a
112 * fatal system error. Used in conjunction with
113 * relinquish_interpreter
115 ******************************************************************************/
117 void acpi_ex_reacquire_interpreter(void)
119 ACPI_FUNCTION_TRACE(ex_reacquire_interpreter);
122 * If the global serialized flag is set, do not release the interpreter,
123 * since it was not actually released by acpi_ex_relinquish_interpreter.
124 * This forces the interpreter to be single threaded.
126 if (!acpi_gbl_all_methods_serialized) {
127 acpi_ex_enter_interpreter();
130 return_VOID;
133 /*******************************************************************************
135 * FUNCTION: acpi_ex_exit_interpreter
137 * PARAMETERS: None
139 * RETURN: None
141 * DESCRIPTION: Exit the interpreter execution region. This is the top level
142 * routine used to exit the interpreter when all processing has
143 * been completed.
145 ******************************************************************************/
147 void acpi_ex_exit_interpreter(void)
149 acpi_status status;
151 ACPI_FUNCTION_TRACE(ex_exit_interpreter);
153 status = acpi_ut_release_mutex(ACPI_MTX_INTERPRETER);
154 if (ACPI_FAILURE(status)) {
155 ACPI_ERROR((AE_INFO,
156 "Could not release AML Interpreter mutex"));
159 return_VOID;
162 /*******************************************************************************
164 * FUNCTION: acpi_ex_relinquish_interpreter
166 * PARAMETERS: None
168 * RETURN: None
170 * DESCRIPTION: Exit the interpreter execution region, from within the
171 * interpreter - before attempting an operation that will possibly
172 * block the running thread.
174 * Cases where the interpreter is unlocked internally
175 * 1) Method to be blocked on a Sleep() AML opcode
176 * 2) Method to be blocked on an Acquire() AML opcode
177 * 3) Method to be blocked on a Wait() AML opcode
178 * 4) Method to be blocked to acquire the global lock
179 * 5) Method to be blocked waiting to execute a serialized control method
180 * that is currently executing
181 * 6) About to invoke a user-installed opregion handler
183 ******************************************************************************/
185 void acpi_ex_relinquish_interpreter(void)
187 ACPI_FUNCTION_TRACE(ex_relinquish_interpreter);
190 * If the global serialized flag is set, do not release the interpreter.
191 * This forces the interpreter to be single threaded.
193 if (!acpi_gbl_all_methods_serialized) {
194 acpi_ex_exit_interpreter();
197 return_VOID;
200 /*******************************************************************************
202 * FUNCTION: acpi_ex_truncate_for32bit_table
204 * PARAMETERS: obj_desc - Object to be truncated
206 * RETURN: none
208 * DESCRIPTION: Truncate an ACPI Integer to 32 bits if the execution mode is
209 * 32-bit, as determined by the revision of the DSDT.
211 ******************************************************************************/
213 void acpi_ex_truncate_for32bit_table(union acpi_operand_object *obj_desc)
216 ACPI_FUNCTION_ENTRY();
219 * Object must be a valid number and we must be executing
220 * a control method. NS node could be there for AML_INT_NAMEPATH_OP.
222 if ((!obj_desc) ||
223 (ACPI_GET_DESCRIPTOR_TYPE(obj_desc) != ACPI_DESC_TYPE_OPERAND) ||
224 (obj_desc->common.type != ACPI_TYPE_INTEGER)) {
225 return;
228 if (acpi_gbl_integer_byte_width == 4) {
230 * We are running a method that exists in a 32-bit ACPI table.
231 * Truncate the value to 32 bits by zeroing out the upper 32-bit field
233 obj_desc->integer.value &= (u64) ACPI_UINT32_MAX;
237 /*******************************************************************************
239 * FUNCTION: acpi_ex_acquire_global_lock
241 * PARAMETERS: field_flags - Flags with Lock rule:
242 * always_lock or never_lock
244 * RETURN: None
246 * DESCRIPTION: Obtain the ACPI hardware Global Lock, only if the field
247 * flags specifiy that it is to be obtained before field access.
249 ******************************************************************************/
251 void acpi_ex_acquire_global_lock(u32 field_flags)
253 acpi_status status;
255 ACPI_FUNCTION_TRACE(ex_acquire_global_lock);
257 /* Only use the lock if the always_lock bit is set */
259 if (!(field_flags & AML_FIELD_LOCK_RULE_MASK)) {
260 return_VOID;
263 /* Attempt to get the global lock, wait forever */
265 status = acpi_ex_acquire_mutex_object(ACPI_WAIT_FOREVER,
266 acpi_gbl_global_lock_mutex,
267 acpi_os_get_thread_id());
269 if (ACPI_FAILURE(status)) {
270 ACPI_EXCEPTION((AE_INFO, status,
271 "Could not acquire Global Lock"));
274 return_VOID;
277 /*******************************************************************************
279 * FUNCTION: acpi_ex_release_global_lock
281 * PARAMETERS: field_flags - Flags with Lock rule:
282 * always_lock or never_lock
284 * RETURN: None
286 * DESCRIPTION: Release the ACPI hardware Global Lock
288 ******************************************************************************/
290 void acpi_ex_release_global_lock(u32 field_flags)
292 acpi_status status;
294 ACPI_FUNCTION_TRACE(ex_release_global_lock);
296 /* Only use the lock if the always_lock bit is set */
298 if (!(field_flags & AML_FIELD_LOCK_RULE_MASK)) {
299 return_VOID;
302 /* Release the global lock */
304 status = acpi_ex_release_mutex_object(acpi_gbl_global_lock_mutex);
305 if (ACPI_FAILURE(status)) {
307 /* Report the error, but there isn't much else we can do */
309 ACPI_EXCEPTION((AE_INFO, status,
310 "Could not release Global Lock"));
313 return_VOID;
316 /*******************************************************************************
318 * FUNCTION: acpi_ex_digits_needed
320 * PARAMETERS: Value - Value to be represented
321 * Base - Base of representation
323 * RETURN: The number of digits.
325 * DESCRIPTION: Calculate the number of digits needed to represent the Value
326 * in the given Base (Radix)
328 ******************************************************************************/
330 static u32 acpi_ex_digits_needed(u64 value, u32 base)
332 u32 num_digits;
333 u64 current_value;
335 ACPI_FUNCTION_TRACE(ex_digits_needed);
337 /* u64 is unsigned, so we don't worry about a '-' prefix */
339 if (value == 0) {
340 return_UINT32(1);
343 current_value = value;
344 num_digits = 0;
346 /* Count the digits in the requested base */
348 while (current_value) {
349 (void)acpi_ut_short_divide(current_value, base, &current_value,
350 NULL);
351 num_digits++;
354 return_UINT32(num_digits);
357 /*******************************************************************************
359 * FUNCTION: acpi_ex_eisa_id_to_string
361 * PARAMETERS: compressed_id - EISAID to be converted
362 * out_string - Where to put the converted string (8 bytes)
364 * RETURN: None
366 * DESCRIPTION: Convert a numeric EISAID to string representation. Return
367 * buffer must be large enough to hold the string. The string
368 * returned is always exactly of length ACPI_EISAID_STRING_SIZE
369 * (includes null terminator). The EISAID is always 32 bits.
371 ******************************************************************************/
373 void acpi_ex_eisa_id_to_string(char *out_string, u64 compressed_id)
375 u32 swapped_id;
377 ACPI_FUNCTION_ENTRY();
379 /* The EISAID should be a 32-bit integer */
381 if (compressed_id > ACPI_UINT32_MAX) {
382 ACPI_WARNING((AE_INFO,
383 "Expected EISAID is larger than 32 bits: 0x%8.8X%8.8X, truncating",
384 ACPI_FORMAT_UINT64(compressed_id)));
387 /* Swap ID to big-endian to get contiguous bits */
389 swapped_id = acpi_ut_dword_byte_swap((u32)compressed_id);
391 /* First 3 bytes are uppercase letters. Next 4 bytes are hexadecimal */
393 out_string[0] =
394 (char)(0x40 + (((unsigned long)swapped_id >> 26) & 0x1F));
395 out_string[1] = (char)(0x40 + ((swapped_id >> 21) & 0x1F));
396 out_string[2] = (char)(0x40 + ((swapped_id >> 16) & 0x1F));
397 out_string[3] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 12);
398 out_string[4] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 8);
399 out_string[5] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 4);
400 out_string[6] = acpi_ut_hex_to_ascii_char((u64) swapped_id, 0);
401 out_string[7] = 0;
404 /*******************************************************************************
406 * FUNCTION: acpi_ex_integer_to_string
408 * PARAMETERS: out_string - Where to put the converted string. At least
409 * 21 bytes are needed to hold the largest
410 * possible 64-bit integer.
411 * Value - Value to be converted
413 * RETURN: None, string
415 * DESCRIPTION: Convert a 64-bit integer to decimal string representation.
416 * Assumes string buffer is large enough to hold the string. The
417 * largest string is (ACPI_MAX64_DECIMAL_DIGITS + 1).
419 ******************************************************************************/
421 void acpi_ex_integer_to_string(char *out_string, u64 value)
423 u32 count;
424 u32 digits_needed;
425 u32 remainder;
427 ACPI_FUNCTION_ENTRY();
429 digits_needed = acpi_ex_digits_needed(value, 10);
430 out_string[digits_needed] = 0;
432 for (count = digits_needed; count > 0; count--) {
433 (void)acpi_ut_short_divide(value, 10, &value, &remainder);
434 out_string[count - 1] = (char)('0' + remainder);
438 /*******************************************************************************
440 * FUNCTION: acpi_is_valid_space_id
442 * PARAMETERS: space_id - ID to be validated
444 * RETURN: TRUE if valid/supported ID.
446 * DESCRIPTION: Validate an operation region space_iD.
448 ******************************************************************************/
450 u8 acpi_is_valid_space_id(u8 space_id)
453 if ((space_id >= ACPI_NUM_PREDEFINED_REGIONS) &&
454 (space_id < ACPI_USER_REGION_BEGIN) &&
455 (space_id != ACPI_ADR_SPACE_DATA_TABLE) &&
456 (space_id != ACPI_ADR_SPACE_FIXED_HARDWARE)) {
457 return (FALSE);
460 return (TRUE);
463 #endif