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/******************************************************************************
 *
 * Module Name: evevent - Fixed Event handling and dispatch
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2019, Intel Corp.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */

#include "acpi.h"
#include "accommon.h"
#include "acevents.h"

#define _COMPONENT          ACPI_EVENTS
        ACPI_MODULE_NAME    ("evevent")

#if (!ACPI_REDUCED_HARDWARE) /* Entire module */

/* Local prototypes */

static ACPI_STATUS
AcpiEvFixedEventInitialize (
    void);

static UINT32
AcpiEvFixedEventDispatch (
    UINT32                  Event);


/*******************************************************************************
 *
 * FUNCTION:    AcpiEvInitializeEvents
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Initialize global data structures for ACPI events (Fixed, GPE)
 *
 ******************************************************************************/

ACPI_STATUS
AcpiEvInitializeEvents (
    void)
{
    ACPI_STATUS             Status;


    ACPI_FUNCTION_TRACE (EvInitializeEvents);


    /* If Hardware Reduced flag is set, there are no fixed events */

    if (AcpiGbl_ReducedHardware)
    {
        return_ACPI_STATUS (AE_OK);
    }

    /*
     * Initialize the Fixed and General Purpose Events. This is done prior to
     * enabling SCIs to prevent interrupts from occurring before the handlers
     * are installed.
     */
    Status = AcpiEvFixedEventInitialize ();
    if (ACPI_FAILURE (Status))
    {
        ACPI_EXCEPTION ((AE_INFO, Status,
            "Unable to initialize fixed events"));
        return_ACPI_STATUS (Status);
    }

    Status = AcpiEvGpeInitialize ();
    if (ACPI_FAILURE (Status))
    {
        ACPI_EXCEPTION ((AE_INFO, Status,
            "Unable to initialize general purpose events"));
        return_ACPI_STATUS (Status);
    }

    return_ACPI_STATUS (Status);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiEvInstallXruptHandlers
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Install interrupt handlers for the SCI and Global Lock
 *
 ******************************************************************************/

ACPI_STATUS
AcpiEvInstallXruptHandlers (
    void)
{
    ACPI_STATUS             Status;


    ACPI_FUNCTION_TRACE (EvInstallXruptHandlers);


    /* If Hardware Reduced flag is set, there is no ACPI h/w */

    if (AcpiGbl_ReducedHardware)
    {
        return_ACPI_STATUS (AE_OK);
    }

    /* Install the SCI handler */

    Status = AcpiEvInstallSciHandler ();
    if (ACPI_FAILURE (Status))
    {
        ACPI_EXCEPTION ((AE_INFO, Status,
            "Unable to install System Control Interrupt handler"));
        return_ACPI_STATUS (Status);
    }

    /* Install the handler for the Global Lock */

    Status = AcpiEvInitGlobalLockHandler ();
    if (ACPI_FAILURE (Status))
    {
        ACPI_EXCEPTION ((AE_INFO, Status,
            "Unable to initialize Global Lock handler"));
        return_ACPI_STATUS (Status);
    }

    AcpiGbl_EventsInitialized = TRUE;
    return_ACPI_STATUS (Status);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiEvFixedEventInitialize
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Install the fixed event handlers and disable all fixed events.
 *
 ******************************************************************************/

static ACPI_STATUS
AcpiEvFixedEventInitialize (
    void)
{
    UINT32                  i;
    ACPI_STATUS             Status;


    /*
     * Initialize the structure that keeps track of fixed event handlers and
     * enable the fixed events.
     */
    for (i = 0; i < ACPI_NUM_FIXED_EVENTS; i++)
    {
        AcpiGbl_FixedEventHandlers[i].Handler = NULL;
        AcpiGbl_FixedEventHandlers[i].Context = NULL;

        /* Disable the fixed event */

        if (AcpiGbl_FixedEventInfo[i].EnableRegisterId != 0xFF)
        {
            Status = AcpiWriteBitRegister (
                AcpiGbl_FixedEventInfo[i].EnableRegisterId,
                ACPI_DISABLE_EVENT);
            if (ACPI_FAILURE (Status))
            {
                return (Status);
            }
        }
    }

    return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiEvFixedEventDetect
 *
 * PARAMETERS:  None
 *
 * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 *
 * DESCRIPTION: Checks the PM status register for active fixed events
 *
 ******************************************************************************/

UINT32
AcpiEvFixedEventDetect (
    void)
{
    UINT32                  IntStatus = ACPI_INTERRUPT_NOT_HANDLED;
    UINT32                  FixedStatus;
    UINT32                  FixedEnable;
    UINT32                  i;
    ACPI_STATUS             Status;


    ACPI_FUNCTION_NAME (EvFixedEventDetect);


    /*
     * Read the fixed feature status and enable registers, as all the cases
     * depend on their values. Ignore errors here.
     */
    Status = AcpiHwRegisterRead (ACPI_REGISTER_PM1_STATUS, &FixedStatus);
    Status |= AcpiHwRegisterRead (ACPI_REGISTER_PM1_ENABLE, &FixedEnable);
    if (ACPI_FAILURE (Status))
    {
        return (IntStatus);
    }

    ACPI_DEBUG_PRINT ((ACPI_DB_INTERRUPTS,
        "Fixed Event Block: Enable %08X Status %08X\n",
        FixedEnable, FixedStatus));

    /*
     * Check for all possible Fixed Events and dispatch those that are active
     */
    for (i = 0; i < ACPI_NUM_FIXED_EVENTS; i++)
    {
        /* Both the status and enable bits must be on for this event */

        if ((FixedStatus & AcpiGbl_FixedEventInfo[i].StatusBitMask) &&
            (FixedEnable & AcpiGbl_FixedEventInfo[i].EnableBitMask))
        {
            /*
             * Found an active (signalled) event. Invoke global event
             * handler if present.
             */
            AcpiFixedEventCount[i]++;
            if (AcpiGbl_GlobalEventHandler)
            {
                AcpiGbl_GlobalEventHandler (ACPI_EVENT_TYPE_FIXED, NULL,
                     i, AcpiGbl_GlobalEventHandlerContext);
            }

            IntStatus |= AcpiEvFixedEventDispatch (i);
        }
    }

    return (IntStatus);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiEvFixedEventDispatch
 *
 * PARAMETERS:  Event               - Event type
 *
 * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 *
 * DESCRIPTION: Clears the status bit for the requested event, calls the
 *              handler that previously registered for the event.
 *              NOTE: If there is no handler for the event, the event is
 *              disabled to prevent further interrupts.
 *
 ******************************************************************************/

static UINT32
AcpiEvFixedEventDispatch (
    UINT32                  Event)
{

    ACPI_FUNCTION_ENTRY ();


    /* Clear the status bit */

    (void) AcpiWriteBitRegister (
        AcpiGbl_FixedEventInfo[Event].StatusRegisterId,
        ACPI_CLEAR_STATUS);

    /*
     * Make sure that a handler exists. If not, report an error
     * and disable the event to prevent further interrupts.
     */
    if (!AcpiGbl_FixedEventHandlers[Event].Handler)
    {
        (void) AcpiWriteBitRegister (
            AcpiGbl_FixedEventInfo[Event].EnableRegisterId,
            ACPI_DISABLE_EVENT);

        ACPI_ERROR ((AE_INFO,
            "No installed handler for fixed event - %s (%u), disabling",
            AcpiUtGetEventName (Event), Event));

        return (ACPI_INTERRUPT_NOT_HANDLED);
    }

    /* Invoke the Fixed Event handler */

    return ((AcpiGbl_FixedEventHandlers[Event].Handler)(
        AcpiGbl_FixedEventHandlers[Event].Context));
}

#endif /* !ACPI_REDUCED_HARDWARE */