1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3 *
4 * Module Name: exsystem - Interface to OS services
5 *
6 * Copyright (C) 2000 - 2023, Intel Corp.
7 *
8 *****************************************************************************/
9
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "acinterp.h"
13
14 #define _COMPONENT ACPI_EXECUTER
15 ACPI_MODULE_NAME("exsystem")
16
17 /*******************************************************************************
18 *
19 * FUNCTION: acpi_ex_system_wait_semaphore
20 *
21 * PARAMETERS: semaphore - Semaphore to wait on
22 * timeout - Max time to wait
23 *
24 * RETURN: Status
25 *
26 * DESCRIPTION: Implements a semaphore wait with a check to see if the
27 * semaphore is available immediately. If it is not, the
28 * interpreter is released before waiting.
29 *
30 ******************************************************************************/
acpi_ex_system_wait_semaphore(acpi_semaphore semaphore,u16 timeout)31 acpi_status acpi_ex_system_wait_semaphore(acpi_semaphore semaphore, u16 timeout)
32 {
33 acpi_status status;
34
35 ACPI_FUNCTION_TRACE(ex_system_wait_semaphore);
36
37 status = acpi_os_wait_semaphore(semaphore, 1, ACPI_DO_NOT_WAIT);
38 if (ACPI_SUCCESS(status)) {
39 return_ACPI_STATUS(status);
40 }
41
42 if (status == AE_TIME) {
43
44 /* We must wait, so unlock the interpreter */
45
46 acpi_ex_exit_interpreter();
47 status = acpi_os_wait_semaphore(semaphore, 1, timeout);
48
49 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
50 "*** Thread awake after blocking, %s\n",
51 acpi_format_exception(status)));
52
53 /* Reacquire the interpreter */
54
55 acpi_ex_enter_interpreter();
56 }
57
58 return_ACPI_STATUS(status);
59 }
60
61 /*******************************************************************************
62 *
63 * FUNCTION: acpi_ex_system_wait_mutex
64 *
65 * PARAMETERS: mutex - Mutex to wait on
66 * timeout - Max time to wait
67 *
68 * RETURN: Status
69 *
70 * DESCRIPTION: Implements a mutex wait with a check to see if the
71 * mutex is available immediately. If it is not, the
72 * interpreter is released before waiting.
73 *
74 ******************************************************************************/
75
acpi_ex_system_wait_mutex(acpi_mutex mutex,u16 timeout)76 acpi_status acpi_ex_system_wait_mutex(acpi_mutex mutex, u16 timeout)
77 {
78 acpi_status status;
79
80 ACPI_FUNCTION_TRACE(ex_system_wait_mutex);
81
82 status = acpi_os_acquire_mutex(mutex, ACPI_DO_NOT_WAIT);
83 if (ACPI_SUCCESS(status)) {
84 return_ACPI_STATUS(status);
85 }
86
87 if (status == AE_TIME) {
88
89 /* We must wait, so unlock the interpreter */
90
91 acpi_ex_exit_interpreter();
92 status = acpi_os_acquire_mutex(mutex, timeout);
93
94 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
95 "*** Thread awake after blocking, %s\n",
96 acpi_format_exception(status)));
97
98 /* Reacquire the interpreter */
99
100 acpi_ex_enter_interpreter();
101 }
102
103 return_ACPI_STATUS(status);
104 }
105
106 /*******************************************************************************
107 *
108 * FUNCTION: acpi_ex_system_do_stall
109 *
110 * PARAMETERS: how_long_us - The amount of time to stall,
111 * in microseconds
112 *
113 * RETURN: Status
114 *
115 * DESCRIPTION: Suspend running thread for specified amount of time.
116 * Note: ACPI specification requires that Stall() does not
117 * relinquish the processor, and delays longer than 100 usec
118 * should use Sleep() instead. We allow stalls up to 255 usec
119 * for compatibility with other interpreters and existing BIOSs.
120 *
121 ******************************************************************************/
122
acpi_ex_system_do_stall(u32 how_long_us)123 acpi_status acpi_ex_system_do_stall(u32 how_long_us)
124 {
125 acpi_status status = AE_OK;
126
127 ACPI_FUNCTION_ENTRY();
128
129 if (how_long_us > 255) {
130 /*
131 * Longer than 255 microseconds, this is an error
132 *
133 * (ACPI specifies 100 usec as max, but this gives some slack in
134 * order to support existing BIOSs)
135 */
136 ACPI_ERROR((AE_INFO,
137 "Time parameter is too large (%u)", how_long_us));
138 status = AE_AML_OPERAND_VALUE;
139 } else {
140 if (how_long_us > 100) {
141 ACPI_WARNING((AE_INFO,
142 "Time parameter %u us > 100 us violating ACPI spec, please fix the firmware.",
143 how_long_us));
144 }
145 acpi_os_stall(how_long_us);
146 }
147
148 return (status);
149 }
150
151 /*******************************************************************************
152 *
153 * FUNCTION: acpi_ex_system_do_sleep
154 *
155 * PARAMETERS: how_long_ms - The amount of time to sleep,
156 * in milliseconds
157 *
158 * RETURN: None
159 *
160 * DESCRIPTION: Sleep the running thread for specified amount of time.
161 *
162 ******************************************************************************/
163
acpi_ex_system_do_sleep(u64 how_long_ms)164 acpi_status acpi_ex_system_do_sleep(u64 how_long_ms)
165 {
166 ACPI_FUNCTION_ENTRY();
167
168 /* Since this thread will sleep, we must release the interpreter */
169
170 acpi_ex_exit_interpreter();
171
172 /*
173 * For compatibility with other ACPI implementations and to prevent
174 * accidental deep sleeps, limit the sleep time to something reasonable.
175 */
176 if (how_long_ms > ACPI_MAX_SLEEP) {
177 how_long_ms = ACPI_MAX_SLEEP;
178 }
179
180 acpi_os_sleep(how_long_ms);
181
182 /* And now we must get the interpreter again */
183
184 acpi_ex_enter_interpreter();
185 return (AE_OK);
186 }
187
188 /*******************************************************************************
189 *
190 * FUNCTION: acpi_ex_system_signal_event
191 *
192 * PARAMETERS: obj_desc - The object descriptor for this op
193 *
194 * RETURN: Status
195 *
196 * DESCRIPTION: Provides an access point to perform synchronization operations
197 * within the AML.
198 *
199 ******************************************************************************/
200
acpi_ex_system_signal_event(union acpi_operand_object * obj_desc)201 acpi_status acpi_ex_system_signal_event(union acpi_operand_object * obj_desc)
202 {
203 acpi_status status = AE_OK;
204
205 ACPI_FUNCTION_TRACE(ex_system_signal_event);
206
207 if (obj_desc) {
208 status =
209 acpi_os_signal_semaphore(obj_desc->event.os_semaphore, 1);
210 }
211
212 return_ACPI_STATUS(status);
213 }
214
215 /*******************************************************************************
216 *
217 * FUNCTION: acpi_ex_system_wait_event
218 *
219 * PARAMETERS: time_desc - The 'time to delay' object descriptor
220 * obj_desc - The object descriptor for this op
221 *
222 * RETURN: Status
223 *
224 * DESCRIPTION: Provides an access point to perform synchronization operations
225 * within the AML. This operation is a request to wait for an
226 * event.
227 *
228 ******************************************************************************/
229
230 acpi_status
acpi_ex_system_wait_event(union acpi_operand_object * time_desc,union acpi_operand_object * obj_desc)231 acpi_ex_system_wait_event(union acpi_operand_object *time_desc,
232 union acpi_operand_object *obj_desc)
233 {
234 acpi_status status = AE_OK;
235
236 ACPI_FUNCTION_TRACE(ex_system_wait_event);
237
238 if (obj_desc) {
239 status =
240 acpi_ex_system_wait_semaphore(obj_desc->event.os_semaphore,
241 (u16) time_desc->integer.
242 value);
243 }
244
245 return_ACPI_STATUS(status);
246 }
247
248 /*******************************************************************************
249 *
250 * FUNCTION: acpi_ex_system_reset_event
251 *
252 * PARAMETERS: obj_desc - The object descriptor for this op
253 *
254 * RETURN: Status
255 *
256 * DESCRIPTION: Reset an event to a known state.
257 *
258 ******************************************************************************/
259
acpi_ex_system_reset_event(union acpi_operand_object * obj_desc)260 acpi_status acpi_ex_system_reset_event(union acpi_operand_object *obj_desc)
261 {
262 acpi_status status = AE_OK;
263 acpi_semaphore temp_semaphore;
264
265 ACPI_FUNCTION_ENTRY();
266
267 /*
268 * We are going to simply delete the existing semaphore and
269 * create a new one!
270 */
271 status =
272 acpi_os_create_semaphore(ACPI_NO_UNIT_LIMIT, 0, &temp_semaphore);
273 if (ACPI_SUCCESS(status)) {
274 (void)acpi_os_delete_semaphore(obj_desc->event.os_semaphore);
275 obj_desc->event.os_semaphore = temp_semaphore;
276 }
277
278 return (status);
279 }
280