Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1
2/******************************************************************************
3 *
4 * Module Name: exsystem - Interface to OS services
5 *
6 *****************************************************************************/
7
8/*
9 * Copyright (C) 2000 - 2008, Intel Corp.
10 * All rights reserved.
11 *
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.
26 *
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.
30 *
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.
43 */
44
45#include <acpi/acpi.h>
46#include <acpi/acinterp.h>
47
48#define _COMPONENT ACPI_EXECUTER
49ACPI_MODULE_NAME("exsystem")
50
51/*******************************************************************************
52 *
53 * FUNCTION: acpi_ex_system_wait_semaphore
54 *
55 * PARAMETERS: Semaphore - Semaphore to wait on
56 * Timeout - Max time to wait
57 *
58 * RETURN: Status
59 *
60 * DESCRIPTION: Implements a semaphore wait with a check to see if the
61 * semaphore is available immediately. If it is not, the
62 * interpreter is released before waiting.
63 *
64 ******************************************************************************/
65acpi_status acpi_ex_system_wait_semaphore(acpi_semaphore semaphore, u16 timeout)
66{
67 acpi_status status;
68
69 ACPI_FUNCTION_TRACE(ex_system_wait_semaphore);
70
71 status = acpi_os_wait_semaphore(semaphore, 1, ACPI_DO_NOT_WAIT);
72 if (ACPI_SUCCESS(status)) {
73 return_ACPI_STATUS(status);
74 }
75
76 if (status == AE_TIME) {
77
78 /* We must wait, so unlock the interpreter */
79
80 acpi_ex_relinquish_interpreter();
81
82 status = acpi_os_wait_semaphore(semaphore, 1, timeout);
83
84 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
85 "*** Thread awake after blocking, %s\n",
86 acpi_format_exception(status)));
87
88 /* Reacquire the interpreter */
89
90 acpi_ex_reacquire_interpreter();
91 }
92
93 return_ACPI_STATUS(status);
94}
95
96/*******************************************************************************
97 *
98 * FUNCTION: acpi_ex_system_wait_mutex
99 *
100 * PARAMETERS: Mutex - Mutex to wait on
101 * Timeout - Max time to wait
102 *
103 * RETURN: Status
104 *
105 * DESCRIPTION: Implements a mutex wait with a check to see if the
106 * mutex is available immediately. If it is not, the
107 * interpreter is released before waiting.
108 *
109 ******************************************************************************/
110
111acpi_status acpi_ex_system_wait_mutex(acpi_mutex mutex, u16 timeout)
112{
113 acpi_status status;
114
115 ACPI_FUNCTION_TRACE(ex_system_wait_mutex);
116
117 status = acpi_os_acquire_mutex(mutex, ACPI_DO_NOT_WAIT);
118 if (ACPI_SUCCESS(status)) {
119 return_ACPI_STATUS(status);
120 }
121
122 if (status == AE_TIME) {
123
124 /* We must wait, so unlock the interpreter */
125
126 acpi_ex_relinquish_interpreter();
127
128 status = acpi_os_acquire_mutex(mutex, timeout);
129
130 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
131 "*** Thread awake after blocking, %s\n",
132 acpi_format_exception(status)));
133
134 /* Reacquire the interpreter */
135
136 acpi_ex_reacquire_interpreter();
137 }
138
139 return_ACPI_STATUS(status);
140}
141
142/*******************************************************************************
143 *
144 * FUNCTION: acpi_ex_system_do_stall
145 *
146 * PARAMETERS: how_long - The amount of time to stall,
147 * in microseconds
148 *
149 * RETURN: Status
150 *
151 * DESCRIPTION: Suspend running thread for specified amount of time.
152 * Note: ACPI specification requires that Stall() does not
153 * relinquish the processor, and delays longer than 100 usec
154 * should use Sleep() instead. We allow stalls up to 255 usec
155 * for compatibility with other interpreters and existing BIOSs.
156 *
157 ******************************************************************************/
158
159acpi_status acpi_ex_system_do_stall(u32 how_long)
160{
161 acpi_status status = AE_OK;
162
163 ACPI_FUNCTION_ENTRY();
164
165 if (how_long > 255) { /* 255 microseconds */
166 /*
167 * Longer than 255 usec, this is an error
168 *
169 * (ACPI specifies 100 usec as max, but this gives some slack in
170 * order to support existing BIOSs)
171 */
172 ACPI_ERROR((AE_INFO, "Time parameter is too large (%d)",
173 how_long));
174 status = AE_AML_OPERAND_VALUE;
175 } else {
176 acpi_os_stall(how_long);
177 }
178
179 return (status);
180}
181
182/*******************************************************************************
183 *
184 * FUNCTION: acpi_ex_system_do_suspend
185 *
186 * PARAMETERS: how_long - The amount of time to suspend,
187 * in milliseconds
188 *
189 * RETURN: None
190 *
191 * DESCRIPTION: Suspend running thread for specified amount of time.
192 *
193 ******************************************************************************/
194
195acpi_status acpi_ex_system_do_suspend(acpi_integer how_long)
196{
197 ACPI_FUNCTION_ENTRY();
198
199 /* Since this thread will sleep, we must release the interpreter */
200
201 acpi_ex_relinquish_interpreter();
202
203 acpi_os_sleep(how_long);
204
205 /* And now we must get the interpreter again */
206
207 acpi_ex_reacquire_interpreter();
208 return (AE_OK);
209}
210
211/*******************************************************************************
212 *
213 * FUNCTION: acpi_ex_system_signal_event
214 *
215 * PARAMETERS: obj_desc - The object descriptor for this op
216 *
217 * RETURN: Status
218 *
219 * DESCRIPTION: Provides an access point to perform synchronization operations
220 * within the AML.
221 *
222 ******************************************************************************/
223
224acpi_status acpi_ex_system_signal_event(union acpi_operand_object * obj_desc)
225{
226 acpi_status status = AE_OK;
227
228 ACPI_FUNCTION_TRACE(ex_system_signal_event);
229
230 if (obj_desc) {
231 status =
232 acpi_os_signal_semaphore(obj_desc->event.os_semaphore, 1);
233 }
234
235 return_ACPI_STATUS(status);
236}
237
238/*******************************************************************************
239 *
240 * FUNCTION: acpi_ex_system_wait_event
241 *
242 * PARAMETERS: time_desc - The 'time to delay' object descriptor
243 * obj_desc - The object descriptor for this op
244 *
245 * RETURN: Status
246 *
247 * DESCRIPTION: Provides an access point to perform synchronization operations
248 * within the AML. This operation is a request to wait for an
249 * event.
250 *
251 ******************************************************************************/
252
253acpi_status
254acpi_ex_system_wait_event(union acpi_operand_object *time_desc,
255 union acpi_operand_object *obj_desc)
256{
257 acpi_status status = AE_OK;
258
259 ACPI_FUNCTION_TRACE(ex_system_wait_event);
260
261 if (obj_desc) {
262 status =
263 acpi_ex_system_wait_semaphore(obj_desc->event.os_semaphore,
264 (u16) time_desc->integer.
265 value);
266 }
267
268 return_ACPI_STATUS(status);
269}
270
271/*******************************************************************************
272 *
273 * FUNCTION: acpi_ex_system_reset_event
274 *
275 * PARAMETERS: obj_desc - The object descriptor for this op
276 *
277 * RETURN: Status
278 *
279 * DESCRIPTION: Reset an event to a known state.
280 *
281 ******************************************************************************/
282
283acpi_status acpi_ex_system_reset_event(union acpi_operand_object *obj_desc)
284{
285 acpi_status status = AE_OK;
286 acpi_semaphore temp_semaphore;
287
288 ACPI_FUNCTION_ENTRY();
289
290 /*
291 * We are going to simply delete the existing semaphore and
292 * create a new one!
293 */
294 status =
295 acpi_os_create_semaphore(ACPI_NO_UNIT_LIMIT, 0, &temp_semaphore);
296 if (ACPI_SUCCESS(status)) {
297 (void)acpi_os_delete_semaphore(obj_desc->event.os_semaphore);
298 obj_desc->event.os_semaphore = temp_semaphore;
299 }
300
301 return (status);
302}