xref: /freebsd/sys/contrib/dev/acpica/components/events/evglock.c (revision 722b16673c40aedf280895f2f2f676bb494518d7)
1 /******************************************************************************
2  *
3  * Module Name: evglock - Global Lock support
4  *
5  *****************************************************************************/
6 
7 /******************************************************************************
8  *
9  * 1. Copyright Notice
10  *
11  * Some or all of this work - Copyright (c) 1999 - 2023, Intel Corp.
12  * All rights reserved.
13  *
14  * 2. License
15  *
16  * 2.1. This is your license from Intel Corp. under its intellectual property
17  * rights. You may have additional license terms from the party that provided
18  * you this software, covering your right to use that party's intellectual
19  * property rights.
20  *
21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
22  * copy of the source code appearing in this file ("Covered Code") an
23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
24  * base code distributed originally by Intel ("Original Intel Code") to copy,
25  * make derivatives, distribute, use and display any portion of the Covered
26  * Code in any form, with the right to sublicense such rights; and
27  *
28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
29  * license (with the right to sublicense), under only those claims of Intel
30  * patents that are infringed by the Original Intel Code, to make, use, sell,
31  * offer to sell, and import the Covered Code and derivative works thereof
32  * solely to the minimum extent necessary to exercise the above copyright
33  * license, and in no event shall the patent license extend to any additions
34  * to or modifications of the Original Intel Code. No other license or right
35  * is granted directly or by implication, estoppel or otherwise;
36  *
37  * The above copyright and patent license is granted only if the following
38  * conditions are met:
39  *
40  * 3. Conditions
41  *
42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
43  * Redistribution of source code of any substantial portion of the Covered
44  * Code or modification with rights to further distribute source must include
45  * the above Copyright Notice, the above License, this list of Conditions,
46  * and the following Disclaimer and Export Compliance provision. In addition,
47  * Licensee must cause all Covered Code to which Licensee contributes to
48  * contain a file documenting the changes Licensee made to create that Covered
49  * Code and the date of any change. Licensee must include in that file the
50  * documentation of any changes made by any predecessor Licensee. Licensee
51  * must include a prominent statement that the modification is derived,
52  * directly or indirectly, from Original Intel Code.
53  *
54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
55  * Redistribution of source code of any substantial portion of the Covered
56  * Code or modification without rights to further distribute source must
57  * include the following Disclaimer and Export Compliance provision in the
58  * documentation and/or other materials provided with distribution. In
59  * addition, Licensee may not authorize further sublicense of source of any
60  * portion of the Covered Code, and must include terms to the effect that the
61  * license from Licensee to its licensee is limited to the intellectual
62  * property embodied in the software Licensee provides to its licensee, and
63  * not to intellectual property embodied in modifications its licensee may
64  * make.
65  *
66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
67  * substantial portion of the Covered Code or modification must reproduce the
68  * above Copyright Notice, and the following Disclaimer and Export Compliance
69  * provision in the documentation and/or other materials provided with the
70  * distribution.
71  *
72  * 3.4. Intel retains all right, title, and interest in and to the Original
73  * Intel Code.
74  *
75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
76  * Intel shall be used in advertising or otherwise to promote the sale, use or
77  * other dealings in products derived from or relating to the Covered Code
78  * without prior written authorization from Intel.
79  *
80  * 4. Disclaimer and Export Compliance
81  *
82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
83  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
85  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
86  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
88  * PARTICULAR PURPOSE.
89  *
90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
97  * LIMITED REMEDY.
98  *
99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
100  * software or system incorporating such software without first obtaining any
101  * required license or other approval from the U. S. Department of Commerce or
102  * any other agency or department of the United States Government. In the
103  * event Licensee exports any such software from the United States or
104  * re-exports any such software from a foreign destination, Licensee shall
105  * ensure that the distribution and export/re-export of the software is in
106  * compliance with all laws, regulations, orders, or other restrictions of the
107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
108  * any of its subsidiaries will export/re-export any technical data, process,
109  * software, or service, directly or indirectly, to any country for which the
110  * United States government or any agency thereof requires an export license,
111  * other governmental approval, or letter of assurance, without first obtaining
112  * such license, approval or letter.
113  *
114  *****************************************************************************
115  *
116  * Alternatively, you may choose to be licensed under the terms of the
117  * following license:
118  *
119  * Redistribution and use in source and binary forms, with or without
120  * modification, are permitted provided that the following conditions
121  * are met:
122  * 1. Redistributions of source code must retain the above copyright
123  *    notice, this list of conditions, and the following disclaimer,
124  *    without modification.
125  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
126  *    substantially similar to the "NO WARRANTY" disclaimer below
127  *    ("Disclaimer") and any redistribution must be conditioned upon
128  *    including a substantially similar Disclaimer requirement for further
129  *    binary redistribution.
130  * 3. Neither the names of the above-listed copyright holders nor the names
131  *    of any contributors may be used to endorse or promote products derived
132  *    from this software without specific prior written permission.
133  *
134  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
135  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
136  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
137  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
138  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
139  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
140  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
141  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
142  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
143  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
144  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
145  *
146  * Alternatively, you may choose to be licensed under the terms of the
147  * GNU General Public License ("GPL") version 2 as published by the Free
148  * Software Foundation.
149  *
150  *****************************************************************************/
151 
152 #include <contrib/dev/acpica/include/acpi.h>
153 #include <contrib/dev/acpica/include/accommon.h>
154 #include <contrib/dev/acpica/include/acevents.h>
155 #include <contrib/dev/acpica/include/acinterp.h>
156 
157 #define _COMPONENT          ACPI_EVENTS
158         ACPI_MODULE_NAME    ("evglock")
159 
160 #if (!ACPI_REDUCED_HARDWARE) /* Entire module */
161 
162 /* Local prototypes */
163 
164 static UINT32
165 AcpiEvGlobalLockHandler (
166     void                    *Context);
167 
168 
169 /*******************************************************************************
170  *
171  * FUNCTION:    AcpiEvInitGlobalLockHandler
172  *
173  * PARAMETERS:  None
174  *
175  * RETURN:      Status
176  *
177  * DESCRIPTION: Install a handler for the global lock release event
178  *
179  ******************************************************************************/
180 
181 ACPI_STATUS
AcpiEvInitGlobalLockHandler(void)182 AcpiEvInitGlobalLockHandler (
183     void)
184 {
185     ACPI_STATUS             Status;
186 
187 
188     ACPI_FUNCTION_TRACE (EvInitGlobalLockHandler);
189 
190 
191     /* If Hardware Reduced flag is set, there is no global lock */
192 
193     if (AcpiGbl_ReducedHardware)
194     {
195         return_ACPI_STATUS (AE_OK);
196     }
197 
198     /* Attempt installation of the global lock handler */
199 
200     Status = AcpiInstallFixedEventHandler (ACPI_EVENT_GLOBAL,
201         AcpiEvGlobalLockHandler, NULL);
202 
203     /*
204      * If the global lock does not exist on this platform, the attempt to
205      * enable GBL_STATUS will fail (the GBL_ENABLE bit will not stick).
206      * Map to AE_OK, but mark global lock as not present. Any attempt to
207      * actually use the global lock will be flagged with an error.
208      */
209     AcpiGbl_GlobalLockPresent = FALSE;
210     if (Status == AE_NO_HARDWARE_RESPONSE)
211     {
212         ACPI_ERROR ((AE_INFO,
213             "No response from Global Lock hardware, disabling lock"));
214 
215         return_ACPI_STATUS (AE_OK);
216     }
217 
218     Status = AcpiOsCreateLock (&AcpiGbl_GlobalLockPendingLock);
219     if (ACPI_FAILURE (Status))
220     {
221         return_ACPI_STATUS (Status);
222     }
223 
224     AcpiGbl_GlobalLockPending = FALSE;
225     AcpiGbl_GlobalLockPresent = TRUE;
226     return_ACPI_STATUS (Status);
227 }
228 
229 
230 /*******************************************************************************
231  *
232  * FUNCTION:    AcpiEvRemoveGlobalLockHandler
233  *
234  * PARAMETERS:  None
235  *
236  * RETURN:      Status
237  *
238  * DESCRIPTION: Remove the handler for the Global Lock
239  *
240  ******************************************************************************/
241 
242 ACPI_STATUS
AcpiEvRemoveGlobalLockHandler(void)243 AcpiEvRemoveGlobalLockHandler (
244     void)
245 {
246     ACPI_STATUS             Status;
247 
248 
249     ACPI_FUNCTION_TRACE (EvRemoveGlobalLockHandler);
250 
251 
252     AcpiGbl_GlobalLockPresent = FALSE;
253     Status = AcpiRemoveFixedEventHandler (ACPI_EVENT_GLOBAL,
254         AcpiEvGlobalLockHandler);
255 
256     AcpiOsDeleteLock (AcpiGbl_GlobalLockPendingLock);
257     return_ACPI_STATUS (Status);
258 }
259 
260 
261 /*******************************************************************************
262  *
263  * FUNCTION:    AcpiEvGlobalLockHandler
264  *
265  * PARAMETERS:  Context         - From thread interface, not used
266  *
267  * RETURN:      ACPI_INTERRUPT_HANDLED
268  *
269  * DESCRIPTION: Invoked directly from the SCI handler when a global lock
270  *              release interrupt occurs. If there is actually a pending
271  *              request for the lock, signal the waiting thread.
272  *
273  ******************************************************************************/
274 
275 static UINT32
AcpiEvGlobalLockHandler(void * Context)276 AcpiEvGlobalLockHandler (
277     void                    *Context)
278 {
279     ACPI_STATUS             Status;
280     ACPI_CPU_FLAGS          Flags;
281 
282 
283     Flags = AcpiOsAcquireLock (AcpiGbl_GlobalLockPendingLock);
284 
285     /*
286      * If a request for the global lock is not actually pending,
287      * we are done. This handles "spurious" global lock interrupts
288      * which are possible (and have been seen) with bad BIOSs.
289      */
290     if (!AcpiGbl_GlobalLockPending)
291     {
292         goto CleanupAndExit;
293     }
294 
295     /*
296      * Send a unit to the global lock semaphore. The actual acquisition
297      * of the global lock will be performed by the waiting thread.
298      */
299     Status = AcpiOsSignalSemaphore (AcpiGbl_GlobalLockSemaphore, 1);
300     if (ACPI_FAILURE (Status))
301     {
302         ACPI_ERROR ((AE_INFO, "Could not signal Global Lock semaphore"));
303     }
304 
305     AcpiGbl_GlobalLockPending = FALSE;
306 
307 
308 CleanupAndExit:
309 
310     AcpiOsReleaseLock (AcpiGbl_GlobalLockPendingLock, Flags);
311     return (ACPI_INTERRUPT_HANDLED);
312 }
313 
314 
315 /******************************************************************************
316  *
317  * FUNCTION:    AcpiEvAcquireGlobalLock
318  *
319  * PARAMETERS:  Timeout         - Max time to wait for the lock, in millisec.
320  *
321  * RETURN:      Status
322  *
323  * DESCRIPTION: Attempt to gain ownership of the Global Lock.
324  *
325  * MUTEX:       Interpreter must be locked
326  *
327  * Note: The original implementation allowed multiple threads to "acquire" the
328  * Global Lock, and the OS would hold the lock until the last thread had
329  * released it. However, this could potentially starve the BIOS out of the
330  * lock, especially in the case where there is a tight handshake between the
331  * Embedded Controller driver and the BIOS. Therefore, this implementation
332  * allows only one thread to acquire the HW Global Lock at a time, and makes
333  * the global lock appear as a standard mutex on the OS side.
334  *
335  *****************************************************************************/
336 
337 ACPI_STATUS
AcpiEvAcquireGlobalLock(UINT16 Timeout)338 AcpiEvAcquireGlobalLock (
339     UINT16                  Timeout)
340 {
341     ACPI_CPU_FLAGS          Flags;
342     ACPI_STATUS             Status;
343     BOOLEAN                 Acquired = FALSE;
344 
345 
346     ACPI_FUNCTION_TRACE (EvAcquireGlobalLock);
347 
348 
349     /*
350      * Only one thread can acquire the GL at a time, the GlobalLockMutex
351      * enforces this. This interface releases the interpreter if we must wait.
352      */
353     Status = AcpiExSystemWaitMutex (AcpiGbl_GlobalLockMutex->Mutex.OsMutex,
354                 Timeout);
355     if (ACPI_FAILURE (Status))
356     {
357         return_ACPI_STATUS (Status);
358     }
359 
360     /*
361      * Update the global lock handle and check for wraparound. The handle is
362      * only used for the external global lock interfaces, but it is updated
363      * here to properly handle the case where a single thread may acquire the
364      * lock via both the AML and the AcpiAcquireGlobalLock interfaces. The
365      * handle is therefore updated on the first acquire from a given thread
366      * regardless of where the acquisition request originated.
367      */
368     AcpiGbl_GlobalLockHandle++;
369     if (AcpiGbl_GlobalLockHandle == 0)
370     {
371         AcpiGbl_GlobalLockHandle = 1;
372     }
373 
374     /*
375      * Make sure that a global lock actually exists. If not, just
376      * treat the lock as a standard mutex.
377      */
378     if (!AcpiGbl_GlobalLockPresent)
379     {
380         AcpiGbl_GlobalLockAcquired = TRUE;
381         return_ACPI_STATUS (AE_OK);
382     }
383 
384     Flags = AcpiOsAcquireLock (AcpiGbl_GlobalLockPendingLock);
385 
386     do
387     {
388         /* Attempt to acquire the actual hardware lock */
389 
390         ACPI_ACQUIRE_GLOBAL_LOCK (AcpiGbl_FACS, Acquired);
391         if (Acquired)
392         {
393             AcpiGbl_GlobalLockAcquired = TRUE;
394             ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
395                 "Acquired hardware Global Lock\n"));
396             break;
397         }
398 
399         /*
400          * Did not get the lock. The pending bit was set above, and
401          * we must now wait until we receive the global lock
402          * released interrupt.
403          */
404         AcpiGbl_GlobalLockPending = TRUE;
405         AcpiOsReleaseLock (AcpiGbl_GlobalLockPendingLock, Flags);
406 
407         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
408             "Waiting for hardware Global Lock\n"));
409 
410         /*
411          * Wait for handshake with the global lock interrupt handler.
412          * This interface releases the interpreter if we must wait.
413          */
414         Status = AcpiExSystemWaitSemaphore (
415             AcpiGbl_GlobalLockSemaphore, ACPI_WAIT_FOREVER);
416 
417         Flags = AcpiOsAcquireLock (AcpiGbl_GlobalLockPendingLock);
418 
419     } while (ACPI_SUCCESS (Status));
420 
421     AcpiGbl_GlobalLockPending = FALSE;
422     AcpiOsReleaseLock (AcpiGbl_GlobalLockPendingLock, Flags);
423 
424     return_ACPI_STATUS (Status);
425 }
426 
427 
428 /*******************************************************************************
429  *
430  * FUNCTION:    AcpiEvReleaseGlobalLock
431  *
432  * PARAMETERS:  None
433  *
434  * RETURN:      Status
435  *
436  * DESCRIPTION: Releases ownership of the Global Lock.
437  *
438  ******************************************************************************/
439 
440 ACPI_STATUS
AcpiEvReleaseGlobalLock(void)441 AcpiEvReleaseGlobalLock (
442     void)
443 {
444     BOOLEAN                 Pending = FALSE;
445     ACPI_STATUS             Status = AE_OK;
446 
447 
448     ACPI_FUNCTION_TRACE (EvReleaseGlobalLock);
449 
450 
451     /* Lock must be already acquired */
452 
453     if (!AcpiGbl_GlobalLockAcquired)
454     {
455         ACPI_WARNING ((AE_INFO,
456             "Cannot release the ACPI Global Lock, it has not been acquired"));
457         return_ACPI_STATUS (AE_NOT_ACQUIRED);
458     }
459 
460     if (AcpiGbl_GlobalLockPresent)
461     {
462         /* Allow any thread to release the lock */
463 
464         ACPI_RELEASE_GLOBAL_LOCK (AcpiGbl_FACS, Pending);
465 
466         /*
467          * If the pending bit was set, we must write GBL_RLS to the control
468          * register
469          */
470         if (Pending)
471         {
472             Status = AcpiWriteBitRegister (
473                 ACPI_BITREG_GLOBAL_LOCK_RELEASE, ACPI_ENABLE_EVENT);
474         }
475 
476         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Released hardware Global Lock\n"));
477     }
478 
479     AcpiGbl_GlobalLockAcquired = FALSE;
480 
481     /* Release the local GL mutex */
482 
483     AcpiOsReleaseMutex (AcpiGbl_GlobalLockMutex->Mutex.OsMutex);
484     return_ACPI_STATUS (Status);
485 }
486 
487 #endif /* !ACPI_REDUCED_HARDWARE */
488