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/******************************************************************************
 *
 * Name: hwesleep.c - ACPI Hardware Sleep/Wake Support functions for the
 *                    extended FADT-V5 sleep registers.
 *
 *****************************************************************************/

/*
 * 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"

#define _COMPONENT          ACPI_HARDWARE
        ACPI_MODULE_NAME    ("hwesleep")


/*******************************************************************************
 *
 * FUNCTION:    AcpiHwExecuteSleepMethod
 *
 * PARAMETERS:  MethodPathname      - Pathname of method to execute
 *              IntegerArgument     - Argument to pass to the method
 *
 * RETURN:      None
 *
 * DESCRIPTION: Execute a sleep/wake related method with one integer argument
 *              and no return value.
 *
 ******************************************************************************/

void
AcpiHwExecuteSleepMethod (
    char                    *MethodPathname,
    UINT32                  IntegerArgument)
{
    ACPI_OBJECT_LIST        ArgList;
    ACPI_OBJECT             Arg;
    ACPI_STATUS             Status;


    ACPI_FUNCTION_TRACE (HwExecuteSleepMethod);


    /* One argument, IntegerArgument; No return value expected */

    ArgList.Count = 1;
    ArgList.Pointer = &Arg;
    Arg.Type = ACPI_TYPE_INTEGER;
    Arg.Integer.Value = (UINT64) IntegerArgument;

    Status = AcpiEvaluateObject (NULL, MethodPathname, &ArgList, NULL);
    if (ACPI_FAILURE (Status) && Status != AE_NOT_FOUND)
    {
        ACPI_EXCEPTION ((AE_INFO, Status, "While executing method %s",
            MethodPathname));
    }

    return_VOID;
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiHwExtendedSleep
 *
 * PARAMETERS:  SleepState          - Which sleep state to enter
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Enter a system sleep state via the extended FADT sleep
 *              registers (V5 FADT).
 *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
 *
 ******************************************************************************/

ACPI_STATUS
AcpiHwExtendedSleep (
    UINT8                   SleepState)
{
    ACPI_STATUS             Status;
    UINT8                   SleepControl;
    UINT64                  SleepStatus;


    ACPI_FUNCTION_TRACE (HwExtendedSleep);


    /* Extended sleep registers must be valid */

    if (!AcpiGbl_FADT.SleepControl.Address ||
        !AcpiGbl_FADT.SleepStatus.Address)
    {
        return_ACPI_STATUS (AE_NOT_EXIST);
    }

    /* Clear wake status (WAK_STS) */

    Status = AcpiWrite ((UINT64) ACPI_X_WAKE_STATUS,
        &AcpiGbl_FADT.SleepStatus);
    if (ACPI_FAILURE (Status))
    {
        return_ACPI_STATUS (Status);
    }

    AcpiGbl_SystemAwakeAndRunning = FALSE;

    /*
     * Set the SLP_TYP and SLP_EN bits.
     *
     * Note: We only use the first value returned by the \_Sx method
     * (AcpiGbl_SleepTypeA) - As per ACPI specification.
     */
    ACPI_DEBUG_PRINT ((ACPI_DB_INIT,
        "Entering sleep state [S%u]\n", SleepState));

    SleepControl = ((AcpiGbl_SleepTypeA << ACPI_X_SLEEP_TYPE_POSITION) &
        ACPI_X_SLEEP_TYPE_MASK) | ACPI_X_SLEEP_ENABLE;

    /* Flush caches, as per ACPI specification */

    ACPI_FLUSH_CPU_CACHE ();

    Status = AcpiOsEnterSleep (SleepState, SleepControl, 0);
    if (Status == AE_CTRL_TERMINATE)
    {
        return_ACPI_STATUS (AE_OK);
    }
    if (ACPI_FAILURE (Status))
    {
        return_ACPI_STATUS (Status);
    }

    Status = AcpiWrite ((UINT64) SleepControl, &AcpiGbl_FADT.SleepControl);
    if (ACPI_FAILURE (Status))
    {
        return_ACPI_STATUS (Status);
    }

    /* Wait for transition back to Working State */

    do
    {
        Status = AcpiRead (&SleepStatus, &AcpiGbl_FADT.SleepStatus);
        if (ACPI_FAILURE (Status))
        {
            return_ACPI_STATUS (Status);
        }

    } while (!(((UINT8) SleepStatus) & ACPI_X_WAKE_STATUS));

    return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiHwExtendedWakePrep
 *
 * PARAMETERS:  SleepState          - Which sleep state we just exited
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Perform first part of OS-independent ACPI cleanup after
 *              a sleep. Called with interrupts ENABLED.
 *
 ******************************************************************************/

ACPI_STATUS
AcpiHwExtendedWakePrep (
    UINT8                   SleepState)
{
    ACPI_STATUS             Status;
    UINT8                   SleepTypeValue;


    ACPI_FUNCTION_TRACE (HwExtendedWakePrep);


    Status = AcpiGetSleepTypeData (ACPI_STATE_S0,
        &AcpiGbl_SleepTypeA, &AcpiGbl_SleepTypeB);
    if (ACPI_SUCCESS (Status))
    {
        SleepTypeValue = ((AcpiGbl_SleepTypeA << ACPI_X_SLEEP_TYPE_POSITION) &
            ACPI_X_SLEEP_TYPE_MASK);

        (void) AcpiWrite ((UINT64) (SleepTypeValue | ACPI_X_SLEEP_ENABLE),
            &AcpiGbl_FADT.SleepControl);
    }

    return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiHwExtendedWake
 *
 * PARAMETERS:  SleepState          - Which sleep state we just exited
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
 *              Called with interrupts ENABLED.
 *
 ******************************************************************************/

ACPI_STATUS
AcpiHwExtendedWake (
    UINT8                   SleepState)
{
    ACPI_FUNCTION_TRACE (HwExtendedWake);


    /* Ensure EnterSleepStatePrep -> EnterSleepState ordering */

    AcpiGbl_SleepTypeA = ACPI_SLEEP_TYPE_INVALID;

    /* Execute the wake methods */

    AcpiHwExecuteSleepMethod (__UNCONST(METHOD_PATHNAME__SST), ACPI_SST_WAKING);
    AcpiHwExecuteSleepMethod (__UNCONST(METHOD_PATHNAME__WAK), SleepState);

    /*
     * Some BIOS code assumes that WAK_STS will be cleared on resume
     * and use it to determine whether the system is rebooting or
     * resuming. Clear WAK_STS for compatibility.
     */
    (void) AcpiWrite ((UINT64) ACPI_X_WAKE_STATUS, &AcpiGbl_FADT.SleepStatus);
    AcpiGbl_SystemAwakeAndRunning = TRUE;

    AcpiHwExecuteSleepMethod (__UNCONST(METHOD_PATHNAME__SST), ACPI_SST_WORKING);
    return_ACPI_STATUS (AE_OK);
}