hwacpi.c File Reference

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

Include dependency graph for hwacpi.c:

Go to the source code of this file.

Macros
#define	_COMPONENT   ACPI_HARDWARE

Functions
ACPI_STATUS	AcpiHwSetMode (UINT32 Mode)
UINT32	AcpiHwGetMode (void)

Macro Definition Documentation

_COMPONENT

#define _COMPONENT   ACPI_HARDWARE

Definition at line 48 of file hwacpi.c.

Function Documentation

AcpiHwGetMode()

UINT32 AcpiHwGetMode

(

void

)

Definition at line 179 of file hwacpi.c.

{
    ACPI_STATUS             Status;
    UINT32                  Value;


    ACPI_FUNCTION_TRACE (HwGetMode);


    /* If the Hardware Reduced flag is set, machine is always in acpi mode */

    if (AcpiGbl_ReducedHardware)
    {
        return_UINT32 (ACPI_SYS_MODE_ACPI);
    }

    /*
     * ACPI 2.0 clarified that if SMI_CMD in FADT is zero,
     * system does not support mode transition.
     */
    if (!AcpiGbl_FADT.SmiCommand)
    {
        return_UINT32 (ACPI_SYS_MODE_ACPI);
    }

    Status = AcpiReadBitRegister (ACPI_BITREG_SCI_ENABLE, &Value);
    if (ACPI_FAILURE (Status))
    {
        return_UINT32 (ACPI_SYS_MODE_LEGACY);
    }

    if (Value)
    {
        return_UINT32 (ACPI_SYS_MODE_ACPI);
    }
    else
    {
        return_UINT32 (ACPI_SYS_MODE_LEGACY);
    }
}

Referenced by AcpiDisable(), AcpiEnable(), AcpiEnableSubsystem(), and AcpiHwSetMode().

AcpiHwSetMode()

ACPI_STATUS AcpiHwSetMode

(

UINT32

Mode

)

Definition at line 66 of file hwacpi.c.

{

    ACPI_STATUS             Status;
    UINT32                  Retry;


    ACPI_FUNCTION_TRACE (HwSetMode);


    /* If the Hardware Reduced flag is set, machine is always in acpi mode */

    if (AcpiGbl_ReducedHardware)
    {
        return_ACPI_STATUS (AE_OK);
    }

    /*
     * ACPI 2.0 clarified that if SMI_CMD in FADT is zero,
     * system does not support mode transition.
     */
    if (!AcpiGbl_FADT.SmiCommand)
    {
        ACPI_ERROR ((AE_INFO, "No SMI_CMD in FADT, mode transition failed"));
        return_ACPI_STATUS (AE_NO_HARDWARE_RESPONSE);
    }

    /*
     * ACPI 2.0 clarified the meaning of ACPI_ENABLE and ACPI_DISABLE
     * in FADT: If it is zero, enabling or disabling is not supported.
     * As old systems may have used zero for mode transition,
     * we make sure both the numbers are zero to determine these
     * transitions are not supported.
     */
    if (!AcpiGbl_FADT.AcpiEnable && !AcpiGbl_FADT.AcpiDisable)
    {
        ACPI_ERROR ((AE_INFO,
            "No ACPI mode transition supported in this system "
            "(enable/disable both zero)"));
        return_ACPI_STATUS (AE_OK);
    }

    switch (Mode)
    {
    case ACPI_SYS_MODE_ACPI:

        /* BIOS should have disabled ALL fixed and GP events */

        Status = AcpiHwWritePort (AcpiGbl_FADT.SmiCommand,
            (UINT32) AcpiGbl_FADT.AcpiEnable, 8);
        ACPI_DEBUG_PRINT ((ACPI_DB_INFO, "Attempting to enable ACPI mode\n"));
        break;

    case ACPI_SYS_MODE_LEGACY:
        /*
         * BIOS should clear all fixed status bits and restore fixed event
         * enable bits to default
         */
        Status = AcpiHwWritePort (AcpiGbl_FADT.SmiCommand,
            (UINT32) AcpiGbl_FADT.AcpiDisable, 8);
        ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
            "Attempting to enable Legacy (non-ACPI) mode\n"));
        break;

    default:

        return_ACPI_STATUS (AE_BAD_PARAMETER);
    }

    if (ACPI_FAILURE (Status))
    {
        ACPI_EXCEPTION ((AE_INFO, Status,
            "Could not write ACPI mode change"));
        return_ACPI_STATUS (Status);
    }

    /*
     * Some hardware takes a LONG time to switch modes. Give them 3 sec to
     * do so, but allow faster systems to proceed more quickly.
     */
    Retry = 3000;
    while (Retry)
    {
        if (AcpiHwGetMode () == Mode)
        {
            ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
                "Mode %X successfully enabled\n", Mode));
            return_ACPI_STATUS (AE_OK);
        }
        AcpiOsStall (ACPI_USEC_PER_MSEC);
        Retry--;
    }

    ACPI_ERROR ((AE_INFO, "Hardware did not change modes"));
    return_ACPI_STATUS (AE_NO_HARDWARE_RESPONSE);
}

Referenced by AcpiDisable(), and AcpiEnable().