126f3cdf0SGordon Ross /******************************************************************************
226f3cdf0SGordon Ross *
326f3cdf0SGordon Ross * Module Name: evglock - Global Lock support
426f3cdf0SGordon Ross *
526f3cdf0SGordon Ross *****************************************************************************/
626f3cdf0SGordon Ross
7*35786f68SRobert Mustacchi /******************************************************************************
8*35786f68SRobert Mustacchi *
9*35786f68SRobert Mustacchi * 1. Copyright Notice
10*35786f68SRobert Mustacchi *
11*35786f68SRobert Mustacchi * Some or all of this work - Copyright (c) 1999 - 2018, Intel Corp.
1226f3cdf0SGordon Ross * All rights reserved.
1326f3cdf0SGordon Ross *
14*35786f68SRobert Mustacchi * 2. License
15*35786f68SRobert Mustacchi *
16*35786f68SRobert Mustacchi * 2.1. This is your license from Intel Corp. under its intellectual property
17*35786f68SRobert Mustacchi * rights. You may have additional license terms from the party that provided
18*35786f68SRobert Mustacchi * you this software, covering your right to use that party's intellectual
19*35786f68SRobert Mustacchi * property rights.
20*35786f68SRobert Mustacchi *
21*35786f68SRobert Mustacchi * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
22*35786f68SRobert Mustacchi * copy of the source code appearing in this file ("Covered Code") an
23*35786f68SRobert Mustacchi * irrevocable, perpetual, worldwide license under Intel's copyrights in the
24*35786f68SRobert Mustacchi * base code distributed originally by Intel ("Original Intel Code") to copy,
25*35786f68SRobert Mustacchi * make derivatives, distribute, use and display any portion of the Covered
26*35786f68SRobert Mustacchi * Code in any form, with the right to sublicense such rights; and
27*35786f68SRobert Mustacchi *
28*35786f68SRobert Mustacchi * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
29*35786f68SRobert Mustacchi * license (with the right to sublicense), under only those claims of Intel
30*35786f68SRobert Mustacchi * patents that are infringed by the Original Intel Code, to make, use, sell,
31*35786f68SRobert Mustacchi * offer to sell, and import the Covered Code and derivative works thereof
32*35786f68SRobert Mustacchi * solely to the minimum extent necessary to exercise the above copyright
33*35786f68SRobert Mustacchi * license, and in no event shall the patent license extend to any additions
34*35786f68SRobert Mustacchi * to or modifications of the Original Intel Code. No other license or right
35*35786f68SRobert Mustacchi * is granted directly or by implication, estoppel or otherwise;
36*35786f68SRobert Mustacchi *
37*35786f68SRobert Mustacchi * The above copyright and patent license is granted only if the following
38*35786f68SRobert Mustacchi * conditions are met:
39*35786f68SRobert Mustacchi *
40*35786f68SRobert Mustacchi * 3. Conditions
41*35786f68SRobert Mustacchi *
42*35786f68SRobert Mustacchi * 3.1. Redistribution of Source with Rights to Further Distribute Source.
43*35786f68SRobert Mustacchi * Redistribution of source code of any substantial portion of the Covered
44*35786f68SRobert Mustacchi * Code or modification with rights to further distribute source must include
45*35786f68SRobert Mustacchi * the above Copyright Notice, the above License, this list of Conditions,
46*35786f68SRobert Mustacchi * and the following Disclaimer and Export Compliance provision. In addition,
47*35786f68SRobert Mustacchi * Licensee must cause all Covered Code to which Licensee contributes to
48*35786f68SRobert Mustacchi * contain a file documenting the changes Licensee made to create that Covered
49*35786f68SRobert Mustacchi * Code and the date of any change. Licensee must include in that file the
50*35786f68SRobert Mustacchi * documentation of any changes made by any predecessor Licensee. Licensee
51*35786f68SRobert Mustacchi * must include a prominent statement that the modification is derived,
52*35786f68SRobert Mustacchi * directly or indirectly, from Original Intel Code.
53*35786f68SRobert Mustacchi *
54*35786f68SRobert Mustacchi * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
55*35786f68SRobert Mustacchi * Redistribution of source code of any substantial portion of the Covered
56*35786f68SRobert Mustacchi * Code or modification without rights to further distribute source must
57*35786f68SRobert Mustacchi * include the following Disclaimer and Export Compliance provision in the
58*35786f68SRobert Mustacchi * documentation and/or other materials provided with distribution. In
59*35786f68SRobert Mustacchi * addition, Licensee may not authorize further sublicense of source of any
60*35786f68SRobert Mustacchi * portion of the Covered Code, and must include terms to the effect that the
61*35786f68SRobert Mustacchi * license from Licensee to its licensee is limited to the intellectual
62*35786f68SRobert Mustacchi * property embodied in the software Licensee provides to its licensee, and
63*35786f68SRobert Mustacchi * not to intellectual property embodied in modifications its licensee may
64*35786f68SRobert Mustacchi * make.
65*35786f68SRobert Mustacchi *
66*35786f68SRobert Mustacchi * 3.3. Redistribution of Executable. Redistribution in executable form of any
67*35786f68SRobert Mustacchi * substantial portion of the Covered Code or modification must reproduce the
68*35786f68SRobert Mustacchi * above Copyright Notice, and the following Disclaimer and Export Compliance
69*35786f68SRobert Mustacchi * provision in the documentation and/or other materials provided with the
70*35786f68SRobert Mustacchi * distribution.
71*35786f68SRobert Mustacchi *
72*35786f68SRobert Mustacchi * 3.4. Intel retains all right, title, and interest in and to the Original
73*35786f68SRobert Mustacchi * Intel Code.
74*35786f68SRobert Mustacchi *
75*35786f68SRobert Mustacchi * 3.5. Neither the name Intel nor any other trademark owned or controlled by
76*35786f68SRobert Mustacchi * Intel shall be used in advertising or otherwise to promote the sale, use or
77*35786f68SRobert Mustacchi * other dealings in products derived from or relating to the Covered Code
78*35786f68SRobert Mustacchi * without prior written authorization from Intel.
79*35786f68SRobert Mustacchi *
80*35786f68SRobert Mustacchi * 4. Disclaimer and Export Compliance
81*35786f68SRobert Mustacchi *
82*35786f68SRobert Mustacchi * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
83*35786f68SRobert Mustacchi * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
84*35786f68SRobert Mustacchi * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
85*35786f68SRobert Mustacchi * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
86*35786f68SRobert Mustacchi * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
87*35786f68SRobert Mustacchi * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
88*35786f68SRobert Mustacchi * PARTICULAR PURPOSE.
89*35786f68SRobert Mustacchi *
90*35786f68SRobert Mustacchi * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
91*35786f68SRobert Mustacchi * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
92*35786f68SRobert Mustacchi * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
93*35786f68SRobert Mustacchi * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
94*35786f68SRobert Mustacchi * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
95*35786f68SRobert Mustacchi * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
96*35786f68SRobert Mustacchi * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
97*35786f68SRobert Mustacchi * LIMITED REMEDY.
98*35786f68SRobert Mustacchi *
99*35786f68SRobert Mustacchi * 4.3. Licensee shall not export, either directly or indirectly, any of this
100*35786f68SRobert Mustacchi * software or system incorporating such software without first obtaining any
101*35786f68SRobert Mustacchi * required license or other approval from the U. S. Department of Commerce or
102*35786f68SRobert Mustacchi * any other agency or department of the United States Government. In the
103*35786f68SRobert Mustacchi * event Licensee exports any such software from the United States or
104*35786f68SRobert Mustacchi * re-exports any such software from a foreign destination, Licensee shall
105*35786f68SRobert Mustacchi * ensure that the distribution and export/re-export of the software is in
106*35786f68SRobert Mustacchi * compliance with all laws, regulations, orders, or other restrictions of the
107*35786f68SRobert Mustacchi * U.S. Export Administration Regulations. Licensee agrees that neither it nor
108*35786f68SRobert Mustacchi * any of its subsidiaries will export/re-export any technical data, process,
109*35786f68SRobert Mustacchi * software, or service, directly or indirectly, to any country for which the
110*35786f68SRobert Mustacchi * United States government or any agency thereof requires an export license,
111*35786f68SRobert Mustacchi * other governmental approval, or letter of assurance, without first obtaining
112*35786f68SRobert Mustacchi * such license, approval or letter.
113*35786f68SRobert Mustacchi *
114*35786f68SRobert Mustacchi *****************************************************************************
115*35786f68SRobert Mustacchi *
116*35786f68SRobert Mustacchi * Alternatively, you may choose to be licensed under the terms of the
117*35786f68SRobert Mustacchi * following license:
118*35786f68SRobert Mustacchi *
11926f3cdf0SGordon Ross * Redistribution and use in source and binary forms, with or without
12026f3cdf0SGordon Ross * modification, are permitted provided that the following conditions
12126f3cdf0SGordon Ross * are met:
12226f3cdf0SGordon Ross * 1. Redistributions of source code must retain the above copyright
12326f3cdf0SGordon Ross * notice, this list of conditions, and the following disclaimer,
12426f3cdf0SGordon Ross * without modification.
12526f3cdf0SGordon Ross * 2. Redistributions in binary form must reproduce at minimum a disclaimer
12626f3cdf0SGordon Ross * substantially similar to the "NO WARRANTY" disclaimer below
12726f3cdf0SGordon Ross * ("Disclaimer") and any redistribution must be conditioned upon
12826f3cdf0SGordon Ross * including a substantially similar Disclaimer requirement for further
12926f3cdf0SGordon Ross * binary redistribution.
13026f3cdf0SGordon Ross * 3. Neither the names of the above-listed copyright holders nor the names
13126f3cdf0SGordon Ross * of any contributors may be used to endorse or promote products derived
13226f3cdf0SGordon Ross * from this software without specific prior written permission.
13326f3cdf0SGordon Ross *
13426f3cdf0SGordon Ross * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
13526f3cdf0SGordon Ross * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
136*35786f68SRobert Mustacchi * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
13726f3cdf0SGordon Ross * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
138*35786f68SRobert Mustacchi * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
139*35786f68SRobert Mustacchi * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
140*35786f68SRobert Mustacchi * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
141*35786f68SRobert Mustacchi * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
142*35786f68SRobert Mustacchi * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
143*35786f68SRobert Mustacchi * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
144*35786f68SRobert Mustacchi * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
145*35786f68SRobert Mustacchi *
146*35786f68SRobert Mustacchi * Alternatively, you may choose to be licensed under the terms of the
147*35786f68SRobert Mustacchi * GNU General Public License ("GPL") version 2 as published by the Free
148*35786f68SRobert Mustacchi * Software Foundation.
149*35786f68SRobert Mustacchi *
150*35786f68SRobert Mustacchi *****************************************************************************/
15126f3cdf0SGordon Ross
15226f3cdf0SGordon Ross #include "acpi.h"
15326f3cdf0SGordon Ross #include "accommon.h"
15426f3cdf0SGordon Ross #include "acevents.h"
15526f3cdf0SGordon Ross #include "acinterp.h"
15626f3cdf0SGordon Ross
15726f3cdf0SGordon Ross #define _COMPONENT ACPI_EVENTS
15826f3cdf0SGordon Ross ACPI_MODULE_NAME ("evglock")
15926f3cdf0SGordon Ross
1607b1019a6SJerry Jelinek #if (!ACPI_REDUCED_HARDWARE) /* Entire module */
16126f3cdf0SGordon Ross
16226f3cdf0SGordon Ross /* Local prototypes */
16326f3cdf0SGordon Ross
16426f3cdf0SGordon Ross static UINT32
16526f3cdf0SGordon Ross AcpiEvGlobalLockHandler (
16626f3cdf0SGordon Ross void *Context);
16726f3cdf0SGordon Ross
16826f3cdf0SGordon Ross
16926f3cdf0SGordon Ross /*******************************************************************************
17026f3cdf0SGordon Ross *
17126f3cdf0SGordon Ross * FUNCTION: AcpiEvInitGlobalLockHandler
17226f3cdf0SGordon Ross *
17326f3cdf0SGordon Ross * PARAMETERS: None
17426f3cdf0SGordon Ross *
17526f3cdf0SGordon Ross * RETURN: Status
17626f3cdf0SGordon Ross *
17726f3cdf0SGordon Ross * DESCRIPTION: Install a handler for the global lock release event
17826f3cdf0SGordon Ross *
17926f3cdf0SGordon Ross ******************************************************************************/
18026f3cdf0SGordon Ross
18126f3cdf0SGordon Ross ACPI_STATUS
AcpiEvInitGlobalLockHandler(void)18226f3cdf0SGordon Ross AcpiEvInitGlobalLockHandler (
18326f3cdf0SGordon Ross void)
18426f3cdf0SGordon Ross {
18526f3cdf0SGordon Ross ACPI_STATUS Status;
18626f3cdf0SGordon Ross
18726f3cdf0SGordon Ross
18826f3cdf0SGordon Ross ACPI_FUNCTION_TRACE (EvInitGlobalLockHandler);
18926f3cdf0SGordon Ross
19026f3cdf0SGordon Ross
1917b1019a6SJerry Jelinek /* If Hardware Reduced flag is set, there is no global lock */
1927b1019a6SJerry Jelinek
1937b1019a6SJerry Jelinek if (AcpiGbl_ReducedHardware)
1947b1019a6SJerry Jelinek {
1957b1019a6SJerry Jelinek return_ACPI_STATUS (AE_OK);
1967b1019a6SJerry Jelinek }
1977b1019a6SJerry Jelinek
19826f3cdf0SGordon Ross /* Attempt installation of the global lock handler */
19926f3cdf0SGordon Ross
20026f3cdf0SGordon Ross Status = AcpiInstallFixedEventHandler (ACPI_EVENT_GLOBAL,
2017b1019a6SJerry Jelinek AcpiEvGlobalLockHandler, NULL);
20226f3cdf0SGordon Ross
20326f3cdf0SGordon Ross /*
20426f3cdf0SGordon Ross * If the global lock does not exist on this platform, the attempt to
20526f3cdf0SGordon Ross * enable GBL_STATUS will fail (the GBL_ENABLE bit will not stick).
20626f3cdf0SGordon Ross * Map to AE_OK, but mark global lock as not present. Any attempt to
20726f3cdf0SGordon Ross * actually use the global lock will be flagged with an error.
20826f3cdf0SGordon Ross */
20926f3cdf0SGordon Ross AcpiGbl_GlobalLockPresent = FALSE;
21026f3cdf0SGordon Ross if (Status == AE_NO_HARDWARE_RESPONSE)
21126f3cdf0SGordon Ross {
21226f3cdf0SGordon Ross ACPI_ERROR ((AE_INFO,
21326f3cdf0SGordon Ross "No response from Global Lock hardware, disabling lock"));
21426f3cdf0SGordon Ross
21526f3cdf0SGordon Ross return_ACPI_STATUS (AE_OK);
21626f3cdf0SGordon Ross }
21726f3cdf0SGordon Ross
21826f3cdf0SGordon Ross Status = AcpiOsCreateLock (&AcpiGbl_GlobalLockPendingLock);
21926f3cdf0SGordon Ross if (ACPI_FAILURE (Status))
22026f3cdf0SGordon Ross {
22126f3cdf0SGordon Ross return_ACPI_STATUS (Status);
22226f3cdf0SGordon Ross }
22326f3cdf0SGordon Ross
22426f3cdf0SGordon Ross AcpiGbl_GlobalLockPending = FALSE;
22526f3cdf0SGordon Ross AcpiGbl_GlobalLockPresent = TRUE;
22626f3cdf0SGordon Ross return_ACPI_STATUS (Status);
22726f3cdf0SGordon Ross }
22826f3cdf0SGordon Ross
22926f3cdf0SGordon Ross
23026f3cdf0SGordon Ross /*******************************************************************************
23126f3cdf0SGordon Ross *
23226f3cdf0SGordon Ross * FUNCTION: AcpiEvRemoveGlobalLockHandler
23326f3cdf0SGordon Ross *
23426f3cdf0SGordon Ross * PARAMETERS: None
23526f3cdf0SGordon Ross *
23626f3cdf0SGordon Ross * RETURN: Status
23726f3cdf0SGordon Ross *
23826f3cdf0SGordon Ross * DESCRIPTION: Remove the handler for the Global Lock
23926f3cdf0SGordon Ross *
24026f3cdf0SGordon Ross ******************************************************************************/
24126f3cdf0SGordon Ross
24226f3cdf0SGordon Ross ACPI_STATUS
AcpiEvRemoveGlobalLockHandler(void)24326f3cdf0SGordon Ross AcpiEvRemoveGlobalLockHandler (
24426f3cdf0SGordon Ross void)
24526f3cdf0SGordon Ross {
24626f3cdf0SGordon Ross ACPI_STATUS Status;
24726f3cdf0SGordon Ross
24826f3cdf0SGordon Ross
24926f3cdf0SGordon Ross ACPI_FUNCTION_TRACE (EvRemoveGlobalLockHandler);
25026f3cdf0SGordon Ross
2517b1019a6SJerry Jelinek
25226f3cdf0SGordon Ross AcpiGbl_GlobalLockPresent = FALSE;
25326f3cdf0SGordon Ross Status = AcpiRemoveFixedEventHandler (ACPI_EVENT_GLOBAL,
2547b1019a6SJerry Jelinek AcpiEvGlobalLockHandler);
25526f3cdf0SGordon Ross
2567b1019a6SJerry Jelinek AcpiOsDeleteLock (AcpiGbl_GlobalLockPendingLock);
25726f3cdf0SGordon Ross return_ACPI_STATUS (Status);
25826f3cdf0SGordon Ross }
25926f3cdf0SGordon Ross
26026f3cdf0SGordon Ross
26126f3cdf0SGordon Ross /*******************************************************************************
26226f3cdf0SGordon Ross *
26326f3cdf0SGordon Ross * FUNCTION: AcpiEvGlobalLockHandler
26426f3cdf0SGordon Ross *
26526f3cdf0SGordon Ross * PARAMETERS: Context - From thread interface, not used
26626f3cdf0SGordon Ross *
26726f3cdf0SGordon Ross * RETURN: ACPI_INTERRUPT_HANDLED
26826f3cdf0SGordon Ross *
26926f3cdf0SGordon Ross * DESCRIPTION: Invoked directly from the SCI handler when a global lock
27026f3cdf0SGordon Ross * release interrupt occurs. If there is actually a pending
27126f3cdf0SGordon Ross * request for the lock, signal the waiting thread.
27226f3cdf0SGordon Ross *
27326f3cdf0SGordon Ross ******************************************************************************/
27426f3cdf0SGordon Ross
27526f3cdf0SGordon Ross static UINT32
AcpiEvGlobalLockHandler(void * Context)27626f3cdf0SGordon Ross AcpiEvGlobalLockHandler (
27726f3cdf0SGordon Ross void *Context)
27826f3cdf0SGordon Ross {
27926f3cdf0SGordon Ross ACPI_STATUS Status;
28026f3cdf0SGordon Ross ACPI_CPU_FLAGS Flags;
28126f3cdf0SGordon Ross
28226f3cdf0SGordon Ross
28326f3cdf0SGordon Ross Flags = AcpiOsAcquireLock (AcpiGbl_GlobalLockPendingLock);
28426f3cdf0SGordon Ross
28526f3cdf0SGordon Ross /*
28626f3cdf0SGordon Ross * If a request for the global lock is not actually pending,
28726f3cdf0SGordon Ross * we are done. This handles "spurious" global lock interrupts
28826f3cdf0SGordon Ross * which are possible (and have been seen) with bad BIOSs.
28926f3cdf0SGordon Ross */
29026f3cdf0SGordon Ross if (!AcpiGbl_GlobalLockPending)
29126f3cdf0SGordon Ross {
29226f3cdf0SGordon Ross goto CleanupAndExit;
29326f3cdf0SGordon Ross }
29426f3cdf0SGordon Ross
29526f3cdf0SGordon Ross /*
29626f3cdf0SGordon Ross * Send a unit to the global lock semaphore. The actual acquisition
29726f3cdf0SGordon Ross * of the global lock will be performed by the waiting thread.
29826f3cdf0SGordon Ross */
29926f3cdf0SGordon Ross Status = AcpiOsSignalSemaphore (AcpiGbl_GlobalLockSemaphore, 1);
30026f3cdf0SGordon Ross if (ACPI_FAILURE (Status))
30126f3cdf0SGordon Ross {
30226f3cdf0SGordon Ross ACPI_ERROR ((AE_INFO, "Could not signal Global Lock semaphore"));
30326f3cdf0SGordon Ross }
30426f3cdf0SGordon Ross
30526f3cdf0SGordon Ross AcpiGbl_GlobalLockPending = FALSE;
30626f3cdf0SGordon Ross
30726f3cdf0SGordon Ross
30826f3cdf0SGordon Ross CleanupAndExit:
30926f3cdf0SGordon Ross
31026f3cdf0SGordon Ross AcpiOsReleaseLock (AcpiGbl_GlobalLockPendingLock, Flags);
31126f3cdf0SGordon Ross return (ACPI_INTERRUPT_HANDLED);
31226f3cdf0SGordon Ross }
31326f3cdf0SGordon Ross
31426f3cdf0SGordon Ross
31526f3cdf0SGordon Ross /******************************************************************************
31626f3cdf0SGordon Ross *
31726f3cdf0SGordon Ross * FUNCTION: AcpiEvAcquireGlobalLock
31826f3cdf0SGordon Ross *
31926f3cdf0SGordon Ross * PARAMETERS: Timeout - Max time to wait for the lock, in millisec.
32026f3cdf0SGordon Ross *
32126f3cdf0SGordon Ross * RETURN: Status
32226f3cdf0SGordon Ross *
32326f3cdf0SGordon Ross * DESCRIPTION: Attempt to gain ownership of the Global Lock.
32426f3cdf0SGordon Ross *
32526f3cdf0SGordon Ross * MUTEX: Interpreter must be locked
32626f3cdf0SGordon Ross *
32726f3cdf0SGordon Ross * Note: The original implementation allowed multiple threads to "acquire" the
32826f3cdf0SGordon Ross * Global Lock, and the OS would hold the lock until the last thread had
32926f3cdf0SGordon Ross * released it. However, this could potentially starve the BIOS out of the
33026f3cdf0SGordon Ross * lock, especially in the case where there is a tight handshake between the
33126f3cdf0SGordon Ross * Embedded Controller driver and the BIOS. Therefore, this implementation
33226f3cdf0SGordon Ross * allows only one thread to acquire the HW Global Lock at a time, and makes
33326f3cdf0SGordon Ross * the global lock appear as a standard mutex on the OS side.
33426f3cdf0SGordon Ross *
33526f3cdf0SGordon Ross *****************************************************************************/
33626f3cdf0SGordon Ross
33726f3cdf0SGordon Ross ACPI_STATUS
AcpiEvAcquireGlobalLock(UINT16 Timeout)33826f3cdf0SGordon Ross AcpiEvAcquireGlobalLock (
33926f3cdf0SGordon Ross UINT16 Timeout)
34026f3cdf0SGordon Ross {
34126f3cdf0SGordon Ross ACPI_CPU_FLAGS Flags;
34226f3cdf0SGordon Ross ACPI_STATUS Status;
34326f3cdf0SGordon Ross BOOLEAN Acquired = FALSE;
34426f3cdf0SGordon Ross
34526f3cdf0SGordon Ross
34626f3cdf0SGordon Ross ACPI_FUNCTION_TRACE (EvAcquireGlobalLock);
34726f3cdf0SGordon Ross
34826f3cdf0SGordon Ross
34926f3cdf0SGordon Ross /*
35026f3cdf0SGordon Ross * Only one thread can acquire the GL at a time, the GlobalLockMutex
35126f3cdf0SGordon Ross * enforces this. This interface releases the interpreter if we must wait.
35226f3cdf0SGordon Ross */
35326f3cdf0SGordon Ross Status = AcpiExSystemWaitMutex (AcpiGbl_GlobalLockMutex->Mutex.OsMutex,
35426f3cdf0SGordon Ross Timeout);
35526f3cdf0SGordon Ross if (ACPI_FAILURE (Status))
35626f3cdf0SGordon Ross {
35726f3cdf0SGordon Ross return_ACPI_STATUS (Status);
35826f3cdf0SGordon Ross }
35926f3cdf0SGordon Ross
36026f3cdf0SGordon Ross /*
36126f3cdf0SGordon Ross * Update the global lock handle and check for wraparound. The handle is
36226f3cdf0SGordon Ross * only used for the external global lock interfaces, but it is updated
36326f3cdf0SGordon Ross * here to properly handle the case where a single thread may acquire the
36426f3cdf0SGordon Ross * lock via both the AML and the AcpiAcquireGlobalLock interfaces. The
36526f3cdf0SGordon Ross * handle is therefore updated on the first acquire from a given thread
36626f3cdf0SGordon Ross * regardless of where the acquisition request originated.
36726f3cdf0SGordon Ross */
36826f3cdf0SGordon Ross AcpiGbl_GlobalLockHandle++;
36926f3cdf0SGordon Ross if (AcpiGbl_GlobalLockHandle == 0)
37026f3cdf0SGordon Ross {
37126f3cdf0SGordon Ross AcpiGbl_GlobalLockHandle = 1;
37226f3cdf0SGordon Ross }
37326f3cdf0SGordon Ross
37426f3cdf0SGordon Ross /*
37526f3cdf0SGordon Ross * Make sure that a global lock actually exists. If not, just
37626f3cdf0SGordon Ross * treat the lock as a standard mutex.
37726f3cdf0SGordon Ross */
37826f3cdf0SGordon Ross if (!AcpiGbl_GlobalLockPresent)
37926f3cdf0SGordon Ross {
38026f3cdf0SGordon Ross AcpiGbl_GlobalLockAcquired = TRUE;
38126f3cdf0SGordon Ross return_ACPI_STATUS (AE_OK);
38226f3cdf0SGordon Ross }
38326f3cdf0SGordon Ross
38426f3cdf0SGordon Ross Flags = AcpiOsAcquireLock (AcpiGbl_GlobalLockPendingLock);
38526f3cdf0SGordon Ross
38626f3cdf0SGordon Ross do
38726f3cdf0SGordon Ross {
38826f3cdf0SGordon Ross /* Attempt to acquire the actual hardware lock */
38926f3cdf0SGordon Ross
39026f3cdf0SGordon Ross ACPI_ACQUIRE_GLOBAL_LOCK (AcpiGbl_FACS, Acquired);
39126f3cdf0SGordon Ross if (Acquired)
39226f3cdf0SGordon Ross {
39326f3cdf0SGordon Ross AcpiGbl_GlobalLockAcquired = TRUE;
39426f3cdf0SGordon Ross ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
39526f3cdf0SGordon Ross "Acquired hardware Global Lock\n"));
39626f3cdf0SGordon Ross break;
39726f3cdf0SGordon Ross }
39826f3cdf0SGordon Ross
39926f3cdf0SGordon Ross /*
40026f3cdf0SGordon Ross * Did not get the lock. The pending bit was set above, and
40126f3cdf0SGordon Ross * we must now wait until we receive the global lock
40226f3cdf0SGordon Ross * released interrupt.
40326f3cdf0SGordon Ross */
40426f3cdf0SGordon Ross AcpiGbl_GlobalLockPending = TRUE;
40526f3cdf0SGordon Ross AcpiOsReleaseLock (AcpiGbl_GlobalLockPendingLock, Flags);
40626f3cdf0SGordon Ross
40726f3cdf0SGordon Ross ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
40826f3cdf0SGordon Ross "Waiting for hardware Global Lock\n"));
40926f3cdf0SGordon Ross
41026f3cdf0SGordon Ross /*
41126f3cdf0SGordon Ross * Wait for handshake with the global lock interrupt handler.
41226f3cdf0SGordon Ross * This interface releases the interpreter if we must wait.
41326f3cdf0SGordon Ross */
4147b1019a6SJerry Jelinek Status = AcpiExSystemWaitSemaphore (
4157b1019a6SJerry Jelinek AcpiGbl_GlobalLockSemaphore, ACPI_WAIT_FOREVER);
41626f3cdf0SGordon Ross
41726f3cdf0SGordon Ross Flags = AcpiOsAcquireLock (AcpiGbl_GlobalLockPendingLock);
41826f3cdf0SGordon Ross
41926f3cdf0SGordon Ross } while (ACPI_SUCCESS (Status));
42026f3cdf0SGordon Ross
42126f3cdf0SGordon Ross AcpiGbl_GlobalLockPending = FALSE;
42226f3cdf0SGordon Ross AcpiOsReleaseLock (AcpiGbl_GlobalLockPendingLock, Flags);
42326f3cdf0SGordon Ross
42426f3cdf0SGordon Ross return_ACPI_STATUS (Status);
42526f3cdf0SGordon Ross }
42626f3cdf0SGordon Ross
42726f3cdf0SGordon Ross
42826f3cdf0SGordon Ross /*******************************************************************************
42926f3cdf0SGordon Ross *
43026f3cdf0SGordon Ross * FUNCTION: AcpiEvReleaseGlobalLock
43126f3cdf0SGordon Ross *
43226f3cdf0SGordon Ross * PARAMETERS: None
43326f3cdf0SGordon Ross *
43426f3cdf0SGordon Ross * RETURN: Status
43526f3cdf0SGordon Ross *
43626f3cdf0SGordon Ross * DESCRIPTION: Releases ownership of the Global Lock.
43726f3cdf0SGordon Ross *
43826f3cdf0SGordon Ross ******************************************************************************/
43926f3cdf0SGordon Ross
44026f3cdf0SGordon Ross ACPI_STATUS
AcpiEvReleaseGlobalLock(void)44126f3cdf0SGordon Ross AcpiEvReleaseGlobalLock (
44226f3cdf0SGordon Ross void)
44326f3cdf0SGordon Ross {
44426f3cdf0SGordon Ross BOOLEAN Pending = FALSE;
44526f3cdf0SGordon Ross ACPI_STATUS Status = AE_OK;
44626f3cdf0SGordon Ross
44726f3cdf0SGordon Ross
44826f3cdf0SGordon Ross ACPI_FUNCTION_TRACE (EvReleaseGlobalLock);
44926f3cdf0SGordon Ross
45026f3cdf0SGordon Ross
45126f3cdf0SGordon Ross /* Lock must be already acquired */
45226f3cdf0SGordon Ross
45326f3cdf0SGordon Ross if (!AcpiGbl_GlobalLockAcquired)
45426f3cdf0SGordon Ross {
45526f3cdf0SGordon Ross ACPI_WARNING ((AE_INFO,
45626f3cdf0SGordon Ross "Cannot release the ACPI Global Lock, it has not been acquired"));
45726f3cdf0SGordon Ross return_ACPI_STATUS (AE_NOT_ACQUIRED);
45826f3cdf0SGordon Ross }
45926f3cdf0SGordon Ross
46026f3cdf0SGordon Ross if (AcpiGbl_GlobalLockPresent)
46126f3cdf0SGordon Ross {
46226f3cdf0SGordon Ross /* Allow any thread to release the lock */
46326f3cdf0SGordon Ross
46426f3cdf0SGordon Ross ACPI_RELEASE_GLOBAL_LOCK (AcpiGbl_FACS, Pending);
46526f3cdf0SGordon Ross
46626f3cdf0SGordon Ross /*
46726f3cdf0SGordon Ross * If the pending bit was set, we must write GBL_RLS to the control
46826f3cdf0SGordon Ross * register
46926f3cdf0SGordon Ross */
47026f3cdf0SGordon Ross if (Pending)
47126f3cdf0SGordon Ross {
47226f3cdf0SGordon Ross Status = AcpiWriteBitRegister (
4737b1019a6SJerry Jelinek ACPI_BITREG_GLOBAL_LOCK_RELEASE, ACPI_ENABLE_EVENT);
47426f3cdf0SGordon Ross }
47526f3cdf0SGordon Ross
47626f3cdf0SGordon Ross ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Released hardware Global Lock\n"));
47726f3cdf0SGordon Ross }
47826f3cdf0SGordon Ross
47926f3cdf0SGordon Ross AcpiGbl_GlobalLockAcquired = FALSE;
48026f3cdf0SGordon Ross
48126f3cdf0SGordon Ross /* Release the local GL mutex */
48226f3cdf0SGordon Ross
48326f3cdf0SGordon Ross AcpiOsReleaseMutex (AcpiGbl_GlobalLockMutex->Mutex.OsMutex);
48426f3cdf0SGordon Ross return_ACPI_STATUS (Status);
48526f3cdf0SGordon Ross }
4867b1019a6SJerry Jelinek
4877b1019a6SJerry Jelinek #endif /* !ACPI_REDUCED_HARDWARE */
488