OcTimerLib.c File Reference

#include <Uefi.h>
#include <IndustryStandard/GenericIch.h>
#include <IndustryStandard/Pci.h>
#include <IndustryStandard/CpuId.h>
#include <Library/BaseLib.h>
#include <Library/OcCpuLib.h>
#include <Library/DebugLib.h>
#include <Library/IoLib.h>
#include <Library/PciLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/TimerLib.h>

Go to the source code of this file.

Functions
STATIC VOID	InternalCpuDelay (IN UINT64 Delay)
UINTN EFIAPI	MicroSecondDelay (IN UINTN MicroSeconds)
UINTN EFIAPI	NanoSecondDelay (IN UINTN NanoSeconds)
UINT64 EFIAPI	GetPerformanceCounter (VOID)
UINT64 EFIAPI	GetPerformanceCounterProperties (OUT UINT64 *StartValue, OPTIONAL OUT UINT64 *EndValue OPTIONAL)
UINT64 EFIAPI	GetTimeInNanoSecond (IN UINT64 Ticks)
UINT64 EFIAPI	GetTscFrequency (VOID)
EFI_STATUS EFIAPI	OcTimerLibConstructor (VOID)

Variables
STATIC UINT64	mTscFrequency = 0

Detailed Description

Copyright (C) 2016, The HermitCrabs Lab. All rights reserved.

All rights reserved.

This program and the accompanying materials are licensed and made available under the terms and conditions of the BSD License which accompanies this distribution. The full text of the license may be found at http://opensource.org/licenses/bsd-license.php

THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

Definition in file OcTimerLib.c.

Function Documentation

GetPerformanceCounter()

UINT64 EFIAPI GetPerformanceCounter

(

VOID

)

Retrieves the current value of a 64-bit free running performance counter.

The counter can either count up by 1 or count down by 1. If the physical performance counter counts by a larger increment, then the counter values must be translated. The properties of the counter can be retrieved from GetPerformanceCounterProperties().

Returns

The current value of the free running performance counter.

Definition at line 139 of file OcTimerLib.c.

GetPerformanceCounterProperties()

UINT64 EFIAPI GetPerformanceCounterProperties	(	OUT UINT64 *	StartValue,
		OPTIONAL OUT UINT64 *EndValue	OPTIONAL )

Retrieves the 64-bit frequency in Hz and the range of performance counter values.

If StartValue is not NULL, then the value that the performance counter starts with immediately after is it rolls over is returned in StartValue. If EndValue is not NULL, then the value that the performance counter end with immediately before it rolls over is returned in EndValue. The 64-bit frequency of the performance counter in Hz is always returned. If StartValue is less than EndValue, then the performance counter counts up. If StartValue is greater than EndValue, then the performance counter counts down. For example, a 64-bit free running counter that counts up would have a StartValue of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.

Parameters

StartValue	The value the performance counter starts with when it rolls over.
EndValue	The value that the performance counter ends with before it rolls over.

Returns

The frequency in Hz.

Definition at line 171 of file OcTimerLib.c.

GetTimeInNanoSecond()

UINT64 EFIAPI GetTimeInNanoSecond

(

IN UINT64

Ticks

)

Converts elapsed ticks of performance counter to time in nanoseconds.

This function converts the elapsed ticks of running performance counter to time value in unit of nanoseconds.

Parameters

Ticks

The number of elapsed ticks of running performance counter.

Returns

The elapsed time in nanoseconds.

Definition at line 200 of file OcTimerLib.c.

GetTscFrequency()

UINT64 EFIAPI GetTscFrequency

(

VOID

)

Return cached PerformanceCounterFrequency value.

Return values

The	timer frequency in use.

Definition at line 243 of file OcTimerLib.c.

InternalCpuDelay()

STATIC VOID InternalCpuDelay

(

IN UINT64

Delay

)

Stalls the CPU for at least the given number of ticks.

Stalls the CPU for at least the given number of ticks. It's invoked by MicroSecondDelay() and NanoSecondDelay().

Parameters

Delay

A period of time to delay in ticks.

Definition at line 42 of file OcTimerLib.c.

MicroSecondDelay()

UINTN EFIAPI MicroSecondDelay

(

IN UINTN

MicroSeconds

)

Stalls the CPU for at least the given number of microseconds.

Stalls the CPU for the number of microseconds specified by MicroSeconds.

Parameters

[in]

MicroSeconds

The minimum number of microseconds to delay.

Returns

MicroSeconds

Definition at line 76 of file OcTimerLib.c.

NanoSecondDelay()

UINTN EFIAPI NanoSecondDelay

(

IN UINTN

NanoSeconds

)

Stalls the CPU for at least the given number of nanoseconds.

Stalls the CPU for the number of nanoseconds specified by NanoSeconds.

Parameters

NanoSeconds

The minimum number of nanoseconds to delay.

Returns

The value of NanoSeconds inputted.

Definition at line 107 of file OcTimerLib.c.

OcTimerLibConstructor()

EFI_STATUS EFIAPI OcTimerLibConstructor

(

VOID

)

The constructor function caches PerformanceCounterFrequency.

Return values

EFI_SUCCESS

The constructor always returns RETURN_SUCCESS.

Definition at line 258 of file OcTimerLib.c.

Variable Documentation

mTscFrequency

STATIC UINT64 mTscFrequency = 0

Definition at line 29 of file OcTimerLib.c.