| 0,0 → 1,439 |
|---|
| /****************************************************************************** |
| * |
| * Module Name: evglock - Global Lock support |
| * |
| *****************************************************************************/ |
| |
| /****************************************************************************** |
| * |
| * 1. Copyright Notice |
| * |
| * Some or all of this work - Copyright (c) 1999 - 2011, Intel Corp. |
| * All rights reserved. |
| * |
| * 2. License |
| * |
| * 2.1. This is your license from Intel Corp. under its intellectual property |
| * rights. You may have additional license terms from the party that provided |
| * you this software, covering your right to use that party's intellectual |
| * property rights. |
| * |
| * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a |
| * copy of the source code appearing in this file ("Covered Code") an |
| * irrevocable, perpetual, worldwide license under Intel's copyrights in the |
| * base code distributed originally by Intel ("Original Intel Code") to copy, |
| * make derivatives, distribute, use and display any portion of the Covered |
| * Code in any form, with the right to sublicense such rights; and |
| * |
| * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent |
| * license (with the right to sublicense), under only those claims of Intel |
| * patents that are infringed by the Original Intel Code, to make, use, sell, |
| * offer to sell, and import the Covered Code and derivative works thereof |
| * solely to the minimum extent necessary to exercise the above copyright |
| * license, and in no event shall the patent license extend to any additions |
| * to or modifications of the Original Intel Code. No other license or right |
| * is granted directly or by implication, estoppel or otherwise; |
| * |
| * The above copyright and patent license is granted only if the following |
| * conditions are met: |
| * |
| * 3. Conditions |
| * |
| * 3.1. Redistribution of Source with Rights to Further Distribute Source. |
| * Redistribution of source code of any substantial portion of the Covered |
| * Code or modification with rights to further distribute source must include |
| * the above Copyright Notice, the above License, this list of Conditions, |
| * and the following Disclaimer and Export Compliance provision. In addition, |
| * Licensee must cause all Covered Code to which Licensee contributes to |
| * contain a file documenting the changes Licensee made to create that Covered |
| * Code and the date of any change. Licensee must include in that file the |
| * documentation of any changes made by any predecessor Licensee. Licensee |
| * must include a prominent statement that the modification is derived, |
| * directly or indirectly, from Original Intel Code. |
| * |
| * 3.2. Redistribution of Source with no Rights to Further Distribute Source. |
| * Redistribution of source code of any substantial portion of the Covered |
| * Code or modification without rights to further distribute source must |
| * include the following Disclaimer and Export Compliance provision in the |
| * documentation and/or other materials provided with distribution. In |
| * addition, Licensee may not authorize further sublicense of source of any |
| * portion of the Covered Code, and must include terms to the effect that the |
| * license from Licensee to its licensee is limited to the intellectual |
| * property embodied in the software Licensee provides to its licensee, and |
| * not to intellectual property embodied in modifications its licensee may |
| * make. |
| * |
| * 3.3. Redistribution of Executable. Redistribution in executable form of any |
| * substantial portion of the Covered Code or modification must reproduce the |
| * above Copyright Notice, and the following Disclaimer and Export Compliance |
| * provision in the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * 3.4. Intel retains all right, title, and interest in and to the Original |
| * Intel Code. |
| * |
| * 3.5. Neither the name Intel nor any other trademark owned or controlled by |
| * Intel shall be used in advertising or otherwise to promote the sale, use or |
| * other dealings in products derived from or relating to the Covered Code |
| * without prior written authorization from Intel. |
| * |
| * 4. Disclaimer and Export Compliance |
| * |
| * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED |
| * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE |
| * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE, |
| * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY |
| * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY |
| * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A |
| * PARTICULAR PURPOSE. |
| * |
| * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES |
| * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR |
| * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT, |
| * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY |
| * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL |
| * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS |
| * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY |
| * LIMITED REMEDY. |
| * |
| * 4.3. Licensee shall not export, either directly or indirectly, any of this |
| * software or system incorporating such software without first obtaining any |
| * required license or other approval from the U. S. Department of Commerce or |
| * any other agency or department of the United States Government. In the |
| * event Licensee exports any such software from the United States or |
| * re-exports any such software from a foreign destination, Licensee shall |
| * ensure that the distribution and export/re-export of the software is in |
| * compliance with all laws, regulations, orders, or other restrictions of the |
| * U.S. Export Administration Regulations. Licensee agrees that neither it nor |
| * any of its subsidiaries will export/re-export any technical data, process, |
| * software, or service, directly or indirectly, to any country for which the |
| * United States government or any agency thereof requires an export license, |
| * other governmental approval, or letter of assurance, without first obtaining |
| * such license, approval or letter. |
| * |
| *****************************************************************************/ |
| |
| #include "acpi.h" |
| #include "accommon.h" |
| #include "acevents.h" |
| #include "acinterp.h" |
| |
| #define _COMPONENT ACPI_EVENTS |
| ACPI_MODULE_NAME ("evglock") |
| |
| |
| /* Local prototypes */ |
| |
| static UINT32 |
| AcpiEvGlobalLockHandler ( |
| void *Context); |
| |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: AcpiEvInitGlobalLockHandler |
| * |
| * PARAMETERS: None |
| * |
| * RETURN: Status |
| * |
| * DESCRIPTION: Install a handler for the global lock release event |
| * |
| ******************************************************************************/ |
| |
| ACPI_STATUS |
| AcpiEvInitGlobalLockHandler ( |
| void) |
| { |
| ACPI_STATUS Status; |
| |
| |
| ACPI_FUNCTION_TRACE (EvInitGlobalLockHandler); |
| |
| |
| /* Attempt installation of the global lock handler */ |
| |
| Status = AcpiInstallFixedEventHandler (ACPI_EVENT_GLOBAL, |
| AcpiEvGlobalLockHandler, NULL); |
| |
| /* |
| * If the global lock does not exist on this platform, the attempt to |
| * enable GBL_STATUS will fail (the GBL_ENABLE bit will not stick). |
| * Map to AE_OK, but mark global lock as not present. Any attempt to |
| * actually use the global lock will be flagged with an error. |
| */ |
| AcpiGbl_GlobalLockPresent = FALSE; |
| if (Status == AE_NO_HARDWARE_RESPONSE) |
| { |
| ACPI_ERROR ((AE_INFO, |
| "No response from Global Lock hardware, disabling lock")); |
| |
| return_ACPI_STATUS (AE_OK); |
| } |
| |
| Status = AcpiOsCreateLock (&AcpiGbl_GlobalLockPendingLock); |
| if (ACPI_FAILURE (Status)) |
| { |
| return_ACPI_STATUS (Status); |
| } |
| |
| AcpiGbl_GlobalLockPending = FALSE; |
| AcpiGbl_GlobalLockPresent = TRUE; |
| return_ACPI_STATUS (Status); |
| } |
| |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: AcpiEvRemoveGlobalLockHandler |
| * |
| * PARAMETERS: None |
| * |
| * RETURN: Status |
| * |
| * DESCRIPTION: Remove the handler for the Global Lock |
| * |
| ******************************************************************************/ |
| |
| ACPI_STATUS |
| AcpiEvRemoveGlobalLockHandler ( |
| void) |
| { |
| ACPI_STATUS Status; |
| |
| |
| ACPI_FUNCTION_TRACE (EvRemoveGlobalLockHandler); |
| |
| AcpiGbl_GlobalLockPresent = FALSE; |
| Status = AcpiRemoveFixedEventHandler (ACPI_EVENT_GLOBAL, |
| AcpiEvGlobalLockHandler); |
| |
| return_ACPI_STATUS (Status); |
| } |
| |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: AcpiEvGlobalLockHandler |
| * |
| * PARAMETERS: Context - From thread interface, not used |
| * |
| * RETURN: ACPI_INTERRUPT_HANDLED |
| * |
| * DESCRIPTION: Invoked directly from the SCI handler when a global lock |
| * release interrupt occurs. If there is actually a pending |
| * request for the lock, signal the waiting thread. |
| * |
| ******************************************************************************/ |
| |
| static UINT32 |
| AcpiEvGlobalLockHandler ( |
| void *Context) |
| { |
| ACPI_STATUS Status; |
| ACPI_CPU_FLAGS Flags; |
| |
| |
| Flags = AcpiOsAcquireLock (AcpiGbl_GlobalLockPendingLock); |
| |
| /* |
| * If a request for the global lock is not actually pending, |
| * we are done. This handles "spurious" global lock interrupts |
| * which are possible (and have been seen) with bad BIOSs. |
| */ |
| if (!AcpiGbl_GlobalLockPending) |
| { |
| goto CleanupAndExit; |
| } |
| |
| /* |
| * Send a unit to the global lock semaphore. The actual acquisition |
| * of the global lock will be performed by the waiting thread. |
| */ |
| Status = AcpiOsSignalSemaphore (AcpiGbl_GlobalLockSemaphore, 1); |
| if (ACPI_FAILURE (Status)) |
| { |
| ACPI_ERROR ((AE_INFO, "Could not signal Global Lock semaphore")); |
| } |
| |
| AcpiGbl_GlobalLockPending = FALSE; |
| |
| |
| CleanupAndExit: |
| |
| AcpiOsReleaseLock (AcpiGbl_GlobalLockPendingLock, Flags); |
| return (ACPI_INTERRUPT_HANDLED); |
| } |
| |
| |
| /****************************************************************************** |
| * |
| * FUNCTION: AcpiEvAcquireGlobalLock |
| * |
| * PARAMETERS: Timeout - Max time to wait for the lock, in millisec. |
| * |
| * RETURN: Status |
| * |
| * DESCRIPTION: Attempt to gain ownership of the Global Lock. |
| * |
| * MUTEX: Interpreter must be locked |
| * |
| * Note: The original implementation allowed multiple threads to "acquire" the |
| * Global Lock, and the OS would hold the lock until the last thread had |
| * released it. However, this could potentially starve the BIOS out of the |
| * lock, especially in the case where there is a tight handshake between the |
| * Embedded Controller driver and the BIOS. Therefore, this implementation |
| * allows only one thread to acquire the HW Global Lock at a time, and makes |
| * the global lock appear as a standard mutex on the OS side. |
| * |
| *****************************************************************************/ |
| |
| ACPI_STATUS |
| AcpiEvAcquireGlobalLock ( |
| UINT16 Timeout) |
| { |
| ACPI_CPU_FLAGS Flags; |
| ACPI_STATUS Status; |
| BOOLEAN Acquired = FALSE; |
| |
| |
| ACPI_FUNCTION_TRACE (EvAcquireGlobalLock); |
| |
| |
| /* |
| * Only one thread can acquire the GL at a time, the GlobalLockMutex |
| * enforces this. This interface releases the interpreter if we must wait. |
| */ |
| Status = AcpiExSystemWaitMutex (AcpiGbl_GlobalLockMutex->Mutex.OsMutex, |
| Timeout); |
| if (ACPI_FAILURE (Status)) |
| { |
| return_ACPI_STATUS (Status); |
| } |
| |
| /* |
| * Update the global lock handle and check for wraparound. The handle is |
| * only used for the external global lock interfaces, but it is updated |
| * here to properly handle the case where a single thread may acquire the |
| * lock via both the AML and the AcpiAcquireGlobalLock interfaces. The |
| * handle is therefore updated on the first acquire from a given thread |
| * regardless of where the acquisition request originated. |
| */ |
| AcpiGbl_GlobalLockHandle++; |
| if (AcpiGbl_GlobalLockHandle == 0) |
| { |
| AcpiGbl_GlobalLockHandle = 1; |
| } |
| |
| /* |
| * Make sure that a global lock actually exists. If not, just |
| * treat the lock as a standard mutex. |
| */ |
| if (!AcpiGbl_GlobalLockPresent) |
| { |
| AcpiGbl_GlobalLockAcquired = TRUE; |
| return_ACPI_STATUS (AE_OK); |
| } |
| |
| Flags = AcpiOsAcquireLock (AcpiGbl_GlobalLockPendingLock); |
| |
| do |
| { |
| /* Attempt to acquire the actual hardware lock */ |
| |
| ACPI_ACQUIRE_GLOBAL_LOCK (AcpiGbl_FACS, Acquired); |
| if (Acquired) |
| { |
| AcpiGbl_GlobalLockAcquired = TRUE; |
| ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, |
| "Acquired hardware Global Lock\n")); |
| break; |
| } |
| |
| /* |
| * Did not get the lock. The pending bit was set above, and |
| * we must now wait until we receive the global lock |
| * released interrupt. |
| */ |
| AcpiGbl_GlobalLockPending = TRUE; |
| AcpiOsReleaseLock (AcpiGbl_GlobalLockPendingLock, Flags); |
| |
| ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, |
| "Waiting for hardware Global Lock\n")); |
| |
| /* |
| * Wait for handshake with the global lock interrupt handler. |
| * This interface releases the interpreter if we must wait. |
| */ |
| Status = AcpiExSystemWaitSemaphore (AcpiGbl_GlobalLockSemaphore, |
| ACPI_WAIT_FOREVER); |
| |
| Flags = AcpiOsAcquireLock (AcpiGbl_GlobalLockPendingLock); |
| |
| } while (ACPI_SUCCESS (Status)); |
| |
| AcpiGbl_GlobalLockPending = FALSE; |
| AcpiOsReleaseLock (AcpiGbl_GlobalLockPendingLock, Flags); |
| |
| return_ACPI_STATUS (Status); |
| } |
| |
| |
| /******************************************************************************* |
| * |
| * FUNCTION: AcpiEvReleaseGlobalLock |
| * |
| * PARAMETERS: None |
| * |
| * RETURN: Status |
| * |
| * DESCRIPTION: Releases ownership of the Global Lock. |
| * |
| ******************************************************************************/ |
| |
| ACPI_STATUS |
| AcpiEvReleaseGlobalLock ( |
| void) |
| { |
| BOOLEAN Pending = FALSE; |
| ACPI_STATUS Status = AE_OK; |
| |
| |
| ACPI_FUNCTION_TRACE (EvReleaseGlobalLock); |
| |
| |
| /* Lock must be already acquired */ |
| |
| if (!AcpiGbl_GlobalLockAcquired) |
| { |
| ACPI_WARNING ((AE_INFO, |
| "Cannot release the ACPI Global Lock, it has not been acquired")); |
| return_ACPI_STATUS (AE_NOT_ACQUIRED); |
| } |
| |
| if (AcpiGbl_GlobalLockPresent) |
| { |
| /* Allow any thread to release the lock */ |
| |
| ACPI_RELEASE_GLOBAL_LOCK (AcpiGbl_FACS, Pending); |
| |
| /* |
| * If the pending bit was set, we must write GBL_RLS to the control |
| * register |
| */ |
| if (Pending) |
| { |
| Status = AcpiWriteBitRegister ( |
| ACPI_BITREG_GLOBAL_LOCK_RELEASE, ACPI_ENABLE_EVENT); |
| } |
| |
| ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Released hardware Global Lock\n")); |
| } |
| |
| AcpiGbl_GlobalLockAcquired = FALSE; |
| |
| /* Release the local GL mutex */ |
| |
| AcpiOsReleaseMutex (AcpiGbl_GlobalLockMutex->Mutex.OsMutex); |
| return_ACPI_STATUS (Status); |
| } |