1/*	$NetBSD: OsdSynch.c,v 1.12 2009/03/31 17:17:47 drochner 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 1.12 2009/03/31 17:17:47 drochner 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
81extern int acpi_suspended;
82
83#include <dev/acpi/acpica.h>
84
85MALLOC_DECLARE(M_ACPI);
86
87#define	_COMPONENT	ACPI_OS_SERVICES
88ACPI_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 */
94struct acpi_semaphore {
95	kcondvar_t as_cv;
96	kmutex_t as_slock;
97	UINT32 as_units;
98	UINT32 as_maxunits;
99};
100
101struct acpi_lock {
102	kmutex_t al_slock;
103};
104
105/*
106 * AcpiOsCreateSemaphore:
107 *
108 *	Create a semaphore.
109 */
110ACPI_STATUS
111AcpiOsCreateSemaphore(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 */
143ACPI_STATUS
144AcpiOsDeleteSemaphore(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 */
165ACPI_STATUS
166AcpiOsWaitSemaphore(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 */
226ACPI_STATUS
227AcpiOsSignalSemaphore(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 */
255ACPI_STATUS
256AcpiOsCreateLock(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 */
281void
282AcpiOsDeleteLock(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 */
302ACPI_CPU_FLAGS
303AcpiOsAcquireLock(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 */
320void
321AcpiOsReleaseLock(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