evgpe.c

acpi tools for linux include acpiexec and acpixtract

    }

    /* A Non-NULL GpeDevice means this is a GPE Block Device */

    ObjDesc = AcpiNsGetAttachedObject ((ACPI_NAMESPACE_NODE *) GpeDevice);
    if (!ObjDesc ||
        !ObjDesc->Device.GpeBlock)
    {
        return (NULL);
    }

    GpeBlock = ObjDesc->Device.GpeBlock;

    if ((GpeNumber >= GpeBlock->BlockBaseNumber) &&
        (GpeNumber < GpeBlock->BlockBaseNumber + (GpeBlock->RegisterCount * 8)))
    {
        return (&GpeBlock->EventInfo[GpeNumber - GpeBlock->BlockBaseNumber]);
    }

    return (NULL);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiEvGpeDetect
 *
 * PARAMETERS:  GpeXruptList        - Interrupt block for this interrupt.
 *                                    Can have multiple GPE blocks attached.
 *
 * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 *
 * DESCRIPTION: Detect if any GP events have occurred.  This function is
 *              executed at interrupt level.
 *
 ******************************************************************************/

UINT32
AcpiEvGpeDetect (
    ACPI_GPE_XRUPT_INFO     *GpeXruptList)
{
    ACPI_STATUS             Status;
    ACPI_GPE_BLOCK_INFO     *GpeBlock;
    ACPI_GPE_REGISTER_INFO  *GpeRegisterInfo;
    UINT32                  IntStatus = ACPI_INTERRUPT_NOT_HANDLED;
    UINT8                   EnabledStatusByte;
    UINT32                  StatusReg;
    UINT32                  EnableReg;
    ACPI_CPU_FLAGS          Flags;
    ACPI_NATIVE_UINT        i;
    ACPI_NATIVE_UINT        j;


    ACPI_FUNCTION_NAME (EvGpeDetect);

    /* Check for the case where there are no GPEs */

    if (!GpeXruptList)
    {
        return (IntStatus);
    }

    /*
     * We need to obtain the GPE lock for both the data structs and registers
     * Note: Not necessary to obtain the hardware lock, since the GPE registers
     * are owned by the GpeLock.
     */
    Flags = AcpiOsAcquireLock (AcpiGbl_GpeLock);

    /* Examine all GPE blocks attached to this interrupt level */

    GpeBlock = GpeXruptList->GpeBlockListHead;
    while (GpeBlock)
    {
        /*
         * Read all of the 8-bit GPE status and enable registers
         * in this GPE block, saving all of them.
         * Find all currently active GP events.
         */
        for (i = 0; i < GpeBlock->RegisterCount; i++)
        {
            /* Get the next status/enable pair */

            GpeRegisterInfo = &GpeBlock->RegisterInfo[i];

            /* Read the Status Register */

            Status = AcpiHwLowLevelRead (ACPI_GPE_REGISTER_WIDTH, &StatusReg,
                        &GpeRegisterInfo->StatusAddress);
            if (ACPI_FAILURE (Status))
            {
                goto UnlockAndExit;
            }

            /* Read the Enable Register */

            Status = AcpiHwLowLevelRead (ACPI_GPE_REGISTER_WIDTH, &EnableReg,
                        &GpeRegisterInfo->EnableAddress);
            if (ACPI_FAILURE (Status))
            {
                goto UnlockAndExit;
            }

            ACPI_DEBUG_PRINT ((ACPI_DB_INTERRUPTS,
                "Read GPE Register at GPE%X: Status=%02X, Enable=%02X\n",
                GpeRegisterInfo->BaseGpeNumber, StatusReg, EnableReg));

            /* Check if there is anything active at all in this register */

            EnabledStatusByte = (UINT8) (StatusReg & EnableReg);
            if (!EnabledStatusByte)
            {
                /* No active GPEs in this register, move on */

                continue;
            }

            /* Now look at the individual GPEs in this byte register */

            for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++)
            {
                /* Examine one GPE bit */

                if (EnabledStatusByte & (1 << j))
                {
                    /*
                     * Found an active GPE. Dispatch the event to a handler
                     * or method.
                     */
                    IntStatus |= AcpiEvGpeDispatch (
                        &GpeBlock->EventInfo[(i * ACPI_GPE_REGISTER_WIDTH) + j],
                        (UINT32) j + GpeRegisterInfo->BaseGpeNumber);
                }
            }
        }

        GpeBlock = GpeBlock->Next;
    }

UnlockAndExit:

    AcpiOsReleaseLock (AcpiGbl_GpeLock, Flags);
    return (IntStatus);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiEvAsynchExecuteGpeMethod
 *
 * PARAMETERS:  Context (GpeEventInfo) - Info for this GPE
 *
 * RETURN:      None
 *
 * DESCRIPTION: Perform the actual execution of a GPE control method. This
 *              function is called from an invocation of AcpiOsExecute and
 *              therefore does NOT execute at interrupt level - so that
 *              the control method itself is not executed in the context of
 *              an interrupt handler.
 *
 ******************************************************************************/

static void ACPI_SYSTEM_XFACE
AcpiEvAsynchExecuteGpeMethod (
    void                    *Context)
{
    ACPI_GPE_EVENT_INFO     *GpeEventInfo = Context;
    ACPI_STATUS             Status;
    ACPI_GPE_EVENT_INFO     *LocalGpeEventInfo;
    ACPI_EVALUATE_INFO      *Info;


    ACPI_FUNCTION_TRACE (EvAsynchExecuteGpeMethod);


    /* Allocate a local GPE block */

    LocalGpeEventInfo = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_GPE_EVENT_INFO));
    if (!LocalGpeEventInfo)
    {
        ACPI_EXCEPTION ((AE_INFO, AE_NO_MEMORY,
            "while handling a GPE"));
        return_VOID;
    }

    Status = AcpiUtAcquireMutex (ACPI_MTX_EVENTS);
    if (ACPI_FAILURE (Status))
    {
        return_VOID;
    }

    /* Must revalidate the GpeNumber/GpeBlock */

    if (!AcpiEvValidGpeEvent (GpeEventInfo))
    {
        Status = AcpiUtReleaseMutex (ACPI_MTX_EVENTS);
        return_VOID;
    }

    /* Set the GPE flags for return to enabled state */

    (void) AcpiEvEnableGpe (GpeEventInfo, FALSE);

    /*
     * Take a snapshot of the GPE info for this level - we copy the
     * info to prevent a race condition with RemoveHandler/RemoveBlock.
     */
    ACPI_MEMCPY (LocalGpeEventInfo, GpeEventInfo,
        sizeof (ACPI_GPE_EVENT_INFO));

    Status = AcpiUtReleaseMutex (ACPI_MTX_EVENTS);
    if (ACPI_FAILURE (Status))
    {
        return_VOID;
    }

    /*
     * Must check for control method type dispatch one more
     * time to avoid race with EvGpeInstallHandler
     */
    if ((LocalGpeEventInfo->Flags & ACPI_GPE_DISPATCH_MASK) ==
            ACPI_GPE_DISPATCH_METHOD)
    {
        /* Allocate the evaluation information block */

        Info = ACPI_ALLOCATE_ZEROED (sizeof (ACPI_EVALUATE_INFO));
        if (!Info)
        {
            Status = AE_NO_MEMORY;
        }
        else
        {
            /*
             * Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the _Lxx/_Exx
             * control method that corresponds to this GPE
             */
            Info->PrefixNode = LocalGpeEventInfo->Dispatch.MethodNode;
            Info->Parameters = ACPI_CAST_PTR (ACPI_OPERAND_OBJECT *, LocalGpeEventInfo);
            Info->ParameterType = ACPI_PARAM_GPE;
            Info->Flags = ACPI_IGNORE_RETURN_VALUE;

            Status = AcpiNsEvaluate (Info);
            ACPI_FREE (Info);
        }

        if (ACPI_FAILURE (Status))
        {
            ACPI_EXCEPTION ((AE_INFO, Status,
                "while evaluating GPE method [%4.4s]",
                AcpiUtGetNodeName (LocalGpeEventInfo->Dispatch.MethodNode)));
        }
    }

    /* Defer enabling of GPE until all notify handlers are done */

    Status = AcpiOsExecute (OSL_NOTIFY_HANDLER,
                AcpiEvAsynchEnableGpe, LocalGpeEventInfo);
    if (ACPI_FAILURE (Status))
    {
        ACPI_FREE (LocalGpeEventInfo);
    }
    return_VOID;
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiEvAsynchEnableGpe
 *
 * PARAMETERS:  Context (GpeEventInfo) - Info for this GPE
 *
 * RETURN:      None
 *
 * DESCRIPTION: Asynchronous clear/enable for GPE. This allows the GPE to
 *              complete (i.e., finish execution of Notify)
 *
 ******************************************************************************/

static void ACPI_SYSTEM_XFACE
AcpiEvAsynchEnableGpe (
    void                    *Context)
{
    ACPI_GPE_EVENT_INFO     *GpeEventInfo = Context;
    ACPI_STATUS             Status;


    if ((GpeEventInfo->Flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
            ACPI_GPE_LEVEL_TRIGGERED)
    {
        /*
         * GPE is level-triggered, we clear the GPE status bit after
         * handling the event.
         */
        Status = AcpiHwClearGpe (GpeEventInfo);
        if (ACPI_FAILURE (Status))
        {
            goto Exit;
        }
    }

    /* Enable this GPE */

    (void) AcpiHwWriteGpeEnableReg (GpeEventInfo);

Exit:
    ACPI_FREE (GpeEventInfo);
    return;
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiEvGpeDispatch
 *
 * PARAMETERS:  GpeEventInfo    - Info for this GPE
 *              GpeNumber       - Number relative to the parent GPE block
 *
 * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 *
 * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
 *              or method (e.g. _Lxx/_Exx) handler.
 *
 *              This function executes at interrupt level.
 *
 ******************************************************************************/

UINT32
AcpiEvGpeDispatch (
    ACPI_GPE_EVENT_INFO     *GpeEventInfo,
    UINT32                  GpeNumber)
{
    ACPI_STATUS             Status;


    ACPI_FUNCTION_TRACE (EvGpeDispatch);


    AcpiGpeCount++;

    /*
     * If edge-triggered, clear the GPE status bit now.  Note that
     * level-triggered events are cleared after the GPE is serviced.
     */
    if ((GpeEventInfo->Flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
            ACPI_GPE_EDGE_TRIGGERED)
    {
        Status = AcpiHwClearGpe (GpeEventInfo);
        if (ACPI_FAILURE (Status))
        {
            ACPI_EXCEPTION ((AE_INFO, Status,
                "Unable to clear GPE[%2X]", GpeNumber));
            return_UINT32 (ACPI_INTERRUPT_NOT_HANDLED);
        }
    }

    if (!AcpiGbl_SystemAwakeAndRunning)
    {
        /*
         * We just woke up because of a wake GPE. Disable any further GPEs
         * until we are fully up and running (Only wake GPEs should be enabled
         * at this time, but we just brute-force disable them all.)
         * 1) We must disable this particular wake GPE so it won't fire again
         * 2) We want to disable all wake GPEs, since we are now awake
         */
        (void) AcpiHwDisableAllGpes ();
    }

    /*
     * Dispatch the GPE to either an installed handler, or the control method
     * associated with this GPE (_Lxx or _Exx). If a handler exists, we invoke
     * it and do not attempt to run the method. If there is neither a handler
     * nor a method, we disable this GPE to prevent further such pointless
     * events from firing.
     */
    switch (GpeEventInfo->Flags & ACPI_GPE_DISPATCH_MASK)
    {
    case ACPI_GPE_DISPATCH_HANDLER:

        /*
         * Invoke the installed handler (at interrupt level)
         * Ignore return status for now.  TBD: leave GPE disabled on error?
         */
        (void) GpeEventInfo->Dispatch.Handler->Address (
                        GpeEventInfo->Dispatch.Handler->Context);

        /* It is now safe to clear level-triggered events. */

        if ((GpeEventInfo->Flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
                ACPI_GPE_LEVEL_TRIGGERED)
        {
            Status = AcpiHwClearGpe (GpeEventInfo);
            if (ACPI_FAILURE (Status))
            {
                ACPI_EXCEPTION ((AE_INFO, Status,
                    "Unable to clear GPE[%2X]", GpeNumber));
                return_UINT32 (ACPI_INTERRUPT_NOT_HANDLED);
            }
        }
        break;

    case ACPI_GPE_DISPATCH_METHOD:

        /*
         * Disable the GPE, so it doesn't keep firing before the method has a
         * chance to run (it runs asynchronously with interrupts enabled).
         */
        Status = AcpiEvDisableGpe (GpeEventInfo);
        if (ACPI_FAILURE (Status))
        {
            ACPI_EXCEPTION ((AE_INFO, Status,
                "Unable to disable GPE[%2X]", GpeNumber));
            return_UINT32 (ACPI_INTERRUPT_NOT_HANDLED);
        }

        /*
         * Execute the method associated with the GPE
         * NOTE: Level-triggered GPEs are cleared after the method completes.
         */
        Status = AcpiOsExecute (OSL_GPE_HANDLER,
                    AcpiEvAsynchExecuteGpeMethod, GpeEventInfo);
        if (ACPI_FAILURE (Status))
        {
            ACPI_EXCEPTION ((AE_INFO, Status,
                "Unable to queue handler for GPE[%2X] - event disabled",
                GpeNumber));
        }
        break;

    default:

        /* No handler or method to run! */

        ACPI_ERROR ((AE_INFO,
            "No handler or method for GPE[%2X], disabling event",
            GpeNumber));

        /*
         * Disable the GPE. The GPE will remain disabled until the ACPI
         * Core Subsystem is restarted, or a handler is installed.
         */
        Status = AcpiEvDisableGpe (GpeEventInfo);
        if (ACPI_FAILURE (Status))
        {
            ACPI_EXCEPTION ((AE_INFO, Status,
                "Unable to disable GPE[%2X]", GpeNumber));
            return_UINT32 (ACPI_INTERRUPT_NOT_HANDLED);
        }
        break;
    }

    return_UINT32 (ACPI_INTERRUPT_HANDLED);
}