hwtimer.c File Reference

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

Include dependency graph for hwtimer.c:

Go to the source code of this file.

Macros
#define	EXPORT_ACPI_INTERFACES
#define	_COMPONENT   ACPI_HARDWARE

Functions
ACPI_STATUS	AcpiGetTimerResolution (UINT32 *Resolution)
ACPI_STATUS	AcpiGetTimer (UINT32 *Ticks)
ACPI_STATUS	AcpiGetTimerDuration (UINT32 StartTicks, UINT32 EndTicks, UINT32 *TimeElapsed)

Macro Definition Documentation

_COMPONENT

#define _COMPONENT   ACPI_HARDWARE

Definition at line 49 of file hwtimer.c.

EXPORT_ACPI_INTERFACES

#define EXPORT_ACPI_INTERFACES

Definition at line 44 of file hwtimer.c.

Function Documentation

AcpiGetTimer()

ACPI_STATUS AcpiGetTimer

(

UINT32 *

Ticks

)

Definition at line 106 of file hwtimer.c.

{
    ACPI_STATUS             Status;
    UINT64                  TimerValue;
 
 
    ACPI_FUNCTION_TRACE (AcpiGetTimer);
 
 
    if (!Ticks)
    {
        return_ACPI_STATUS (AE_BAD_PARAMETER);
    }
 
    /* ACPI 5.0A: PM Timer is optional */
 
    if (!AcpiGbl_FADT.XPmTimerBlock.Address)
    {
        return_ACPI_STATUS (AE_SUPPORT);
    }
 
    Status = AcpiHwRead (&TimerValue, &AcpiGbl_FADT.XPmTimerBlock);
    if (ACPI_SUCCESS (Status))
    {
        /* ACPI PM Timer is defined to be 32 bits (PM_TMR_LEN) */
 
        *Ticks = (UINT32) TimerValue;
    }
 
    return_ACPI_STATUS (Status);
}

Referenced by AcpiGetTimer().

AcpiGetTimerDuration()

ACPI_STATUS AcpiGetTimerDuration	(	UINT32	StartTicks,
		UINT32	EndTicks,
		UINT32 *	TimeElapsed
	)

Definition at line 172 of file hwtimer.c.

{
    ACPI_STATUS             Status;
    UINT64                  DeltaTicks;
    UINT64                  Quotient;
 
 
    ACPI_FUNCTION_TRACE (AcpiGetTimerDuration);
 
 
    if (!TimeElapsed)
    {
        return_ACPI_STATUS (AE_BAD_PARAMETER);
    }
 
    /* ACPI 5.0A: PM Timer is optional */
 
    if (!AcpiGbl_FADT.XPmTimerBlock.Address)
    {
        return_ACPI_STATUS (AE_SUPPORT);
    }
 
    if (StartTicks == EndTicks)
    {
        *TimeElapsed = 0;
        return_ACPI_STATUS (AE_OK);
    }
 
    /*
     * Compute Tick Delta:
     * Handle (max one) timer rollovers on 24-bit versus 32-bit timers.
     */
    DeltaTicks = EndTicks;
    if (StartTicks > EndTicks)
    {
        if ((AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER) == 0)
        {
            /* 24-bit Timer */
 
            DeltaTicks |= (UINT64) 1 << 24;
        }
        else
        {
            /* 32-bit Timer */
 
            DeltaTicks |= (UINT64) 1 << 32;
        }
    }
    DeltaTicks -= StartTicks;
 
    /*
     * Compute Duration (Requires a 64-bit multiply and divide):
     *
     * TimeElapsed (microseconds) =
     *  (DeltaTicks * ACPI_USEC_PER_SEC) / ACPI_PM_TIMER_FREQUENCY;
     */
    Status = AcpiUtShortDivide (DeltaTicks * ACPI_USEC_PER_SEC,
                ACPI_PM_TIMER_FREQUENCY, &Quotient, NULL);
 
    *TimeElapsed = (UINT32) Quotient;
    return_ACPI_STATUS (Status);
}

Referenced by AcpiGetTimerDuration().

AcpiGetTimerResolution()

ACPI_STATUS AcpiGetTimerResolution

(

UINT32 *

Resolution

)

Definition at line 67 of file hwtimer.c.

{
    ACPI_FUNCTION_TRACE (AcpiGetTimerResolution);
 
 
    if (!Resolution)
    {
        return_ACPI_STATUS (AE_BAD_PARAMETER);
    }
 
    if ((AcpiGbl_FADT.Flags & ACPI_FADT_32BIT_TIMER) == 0)
    {
        *Resolution = 24;
    }
    else
    {
        *Resolution = 32;
    }
 
    return_ACPI_STATUS (AE_OK);
}

Referenced by AcpiGetTimerResolution().