1 /*        $NetBSD: OsdSynch.c,v 1.13 2009/08/18 16:41:02 jmcneill Exp $         */
2 
3 /*
4  * Copyright 2001 Wasabi Systems, Inc.
5  * All rights reserved.
6  *
7  * Written by Jason R. Thorpe for Wasabi Systems, Inc.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *        This product includes software developed for the NetBSD Project by
20  *        Wasabi Systems, Inc.
21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22  *    or promote products derived from this software without specific prior
23  *    written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 /*-
39  * Copyright (c) 2000 Michael Smith
40  * Copyright (c) 2000 BSDi
41  * All rights reserved.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  *
52  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62  * SUCH DAMAGE.
63  */
64 
65 /*
66  * OS Services Layer
67  *
68  * 6.4: Mutual Exclusion and Synchronization
69  */
70 
71 #include <sys/cdefs.h>
72 __KERNEL_RCSID(0, "$NetBSD: OsdSynch.c,v 1.13 2009/08/18 16:41:02 jmcneill Exp $");
73 
74 #include <sys/param.h>
75 #include <sys/malloc.h>
76 #include <sys/mutex.h>
77 #include <sys/condvar.h>
78 #include <sys/kernel.h>
79 #include <sys/proc.h>
80 
81 extern int acpi_suspended;
82 
83 #include <dev/acpi/acpica.h>
84 
85 MALLOC_DECLARE(M_ACPI);
86 
87 #define   _COMPONENT          ACPI_OS_SERVICES
88 ACPI_MODULE_NAME("SYNCH")
89 
90 /*
91  * Simple counting semaphore implemented using a mutex.  This is
92  * subsequently used in the OSI code to implement a mutex.  Go figure.
93  */
94 struct acpi_semaphore {
95           kcondvar_t as_cv;
96           kmutex_t as_slock;
97           UINT32 as_units;
98           UINT32 as_maxunits;
99 };
100 
101 struct acpi_lock {
102           kmutex_t al_slock;
103 };
104 
105 /*
106  * AcpiOsCreateSemaphore:
107  *
108  *        Create a semaphore.
109  */
110 ACPI_STATUS
AcpiOsCreateSemaphore(UINT32 MaxUnits,UINT32 InitialUnits,ACPI_HANDLE * OutHandle)111 AcpiOsCreateSemaphore(UINT32 MaxUnits, UINT32 InitialUnits,
112     ACPI_HANDLE *OutHandle)
113 {
114           struct acpi_semaphore *as;
115 
116           if (OutHandle == NULL)
117                     return AE_BAD_PARAMETER;
118           if (InitialUnits > MaxUnits)
119                     return AE_BAD_PARAMETER;
120 
121           as = malloc(sizeof(*as), M_ACPI, M_NOWAIT);
122           if (as == NULL)
123                     return AE_NO_MEMORY;
124 
125           mutex_init(&as->as_slock, MUTEX_DEFAULT, IPL_NONE);
126           cv_init(&as->as_cv, "acpisem");
127           as->as_units = InitialUnits;
128           as->as_maxunits = MaxUnits;
129 
130           ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
131               "created semaphore %p max %u initial %u\n",
132               as, as->as_maxunits, as->as_units));
133 
134           *OutHandle = (ACPI_HANDLE) as;
135           return AE_OK;
136 }
137 
138 /*
139  * AcpiOsDeleteSemaphore:
140  *
141  *        Delete a semaphore.
142  */
143 ACPI_STATUS
AcpiOsDeleteSemaphore(ACPI_HANDLE Handle)144 AcpiOsDeleteSemaphore(ACPI_HANDLE Handle)
145 {
146           struct acpi_semaphore *as = (void *) Handle;
147 
148           if (as == NULL)
149                     return AE_BAD_PARAMETER;
150 
151           cv_destroy(&as->as_cv);
152           mutex_destroy(&as->as_slock);
153           free(as, M_ACPI);
154 
155           ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "destroyed semaphore %p\n", as));
156 
157           return AE_OK;
158 }
159 
160 /*
161  * AcpiOsWaitSemaphore:
162  *
163  *        Wait for units from a semaphore.
164  */
165 ACPI_STATUS
AcpiOsWaitSemaphore(ACPI_SEMAPHORE Handle,UINT32 Units,UINT16 Timeout)166 AcpiOsWaitSemaphore(ACPI_SEMAPHORE Handle, UINT32 Units, UINT16 Timeout)
167 {
168           struct acpi_semaphore *as = (void *) Handle;
169           ACPI_STATUS rv;
170           int timo, error;
171 
172           /*
173            * This implementation has a bug: It has to stall for the entire
174            * timeout before it will return AE_TIME.  A better implementation
175            * would adjust the amount of time left after being awakened.
176            */
177 
178           if (as == NULL)
179                     return AE_BAD_PARAMETER;
180           if (cold || doing_shutdown || acpi_suspended)
181                     return AE_OK;
182 
183           /* A timeout of 0xFFFF means "forever". */
184           if (Timeout == 0xFFFF)
185                     timo = 0;
186           else {
187                     /* Compute the timeout using uSec per tick. */
188                     timo = (Timeout * 1000) / (1000000 / hz);
189                     if (timo <= 0)
190                               timo = 1;
191           }
192 
193           mutex_enter(&as->as_slock);
194 
195           ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
196               "get %d units from semaphore %p (has %d) timeout %d\n",
197               Units, as, as->as_units, Timeout));
198 
199           for (;;) {
200                     if (as->as_units >= Units) {
201                               as->as_units -= Units;
202                               rv = AE_OK;
203                               break;
204                     }
205 
206                     ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
207                         "semaphore blocked, sleeping %d ticks\n", timo));
208 
209                     error = cv_timedwait(&as->as_cv, &as->as_slock, timo);
210                     if (error == EWOULDBLOCK) {
211                               rv = AE_TIME;
212                               break;
213                     }
214           }
215 
216           mutex_exit(&as->as_slock);
217 
218           return rv;
219 }
220 
221 /*
222  * AcpiOsSignalSemaphore:
223  *
224  *        Send units to a semaphore.
225  */
226 ACPI_STATUS
AcpiOsSignalSemaphore(ACPI_HANDLE Handle,UINT32 Units)227 AcpiOsSignalSemaphore(ACPI_HANDLE Handle, UINT32 Units)
228 {
229           struct acpi_semaphore *as = (void *) Handle;
230 
231           if (as == NULL)
232                     return AE_BAD_PARAMETER;
233 
234           mutex_enter(&as->as_slock);
235 
236           ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
237               "return %d units to semaphore %p (has %d)\n",
238               Units, as, as->as_units));
239 
240           as->as_units += Units;
241           if (as->as_units > as->as_maxunits)
242                     as->as_units = as->as_maxunits;
243           cv_broadcast(&as->as_cv);
244 
245           mutex_exit(&as->as_slock);
246 
247           return AE_OK;
248 }
249 
250 /*
251  * AcpiOsCreateLock:
252  *
253  *        Create a lock.
254  */
255 ACPI_STATUS
AcpiOsCreateLock(ACPI_HANDLE * OutHandle)256 AcpiOsCreateLock(ACPI_HANDLE *OutHandle)
257 {
258           struct acpi_lock *al;
259 
260           if (OutHandle == NULL)
261                     return AE_BAD_PARAMETER;
262 
263           al = malloc(sizeof(*al), M_ACPI, M_NOWAIT);
264           if (al == NULL)
265                     return AE_NO_MEMORY;
266 
267           mutex_init(&al->al_slock, MUTEX_DEFAULT, IPL_VM);
268 
269           ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
270               "created lock %p\n", al));
271 
272           *OutHandle = (ACPI_HANDLE) al;
273           return AE_OK;
274 }
275 
276 /*
277  * AcpiOsDeleteLock:
278  *
279  *        Delete a lock.
280  */
281 void
AcpiOsDeleteLock(ACPI_SPINLOCK Handle)282 AcpiOsDeleteLock(ACPI_SPINLOCK Handle)
283 {
284           struct acpi_lock *al = (void *) Handle;
285 
286           if (al == NULL)
287                     return;
288 
289           mutex_destroy(&al->al_slock);
290           free(al, M_ACPI);
291 
292           ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "destroyed lock %p\n", al));
293 
294           return;
295 }
296 
297 /*
298  * AcpiOsAcquireLock:
299  *
300  *        Acquire a lock.
301  */
302 ACPI_CPU_FLAGS
AcpiOsAcquireLock(ACPI_SPINLOCK Handle)303 AcpiOsAcquireLock(ACPI_SPINLOCK Handle)
304 {
305           struct acpi_lock *al = (void *) Handle;
306 
307           if (al == NULL)
308                     return 0;
309 
310           mutex_enter(&al->al_slock);
311 
312           return 0;
313 }
314 
315 /*
316  * AcpiOsReleaseLock:
317  *
318  *        Release a lock.
319  */
320 void
AcpiOsReleaseLock(ACPI_HANDLE Handle,ACPI_CPU_FLAGS Flags)321 AcpiOsReleaseLock(ACPI_HANDLE Handle, ACPI_CPU_FLAGS Flags)
322 {
323           struct acpi_lock *al = (void *) Handle;
324 
325           if (al == NULL)
326                     return;
327 
328           mutex_exit(&al->al_slock);
329 
330           return;
331 }
332