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Diffstat (limited to 'MdePkg/Include/Library/TimerLib.h')
-rw-r--r-- | MdePkg/Include/Library/TimerLib.h | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/MdePkg/Include/Library/TimerLib.h b/MdePkg/Include/Library/TimerLib.h new file mode 100644 index 000000000000..f0d898a9894f --- /dev/null +++ b/MdePkg/Include/Library/TimerLib.h @@ -0,0 +1,114 @@ +/** @file + Provides calibrated delay and performance counter services. + +Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR> +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. + +**/ + +#ifndef __TIMER_LIB__ +#define __TIMER_LIB__ + +/** + Stalls the CPU for at least the given number of microseconds. + + Stalls the CPU for the number of microseconds specified by MicroSeconds. + + @param MicroSeconds The minimum number of microseconds to delay. + + @return The value of MicroSeconds inputted. + +**/ +UINTN +EFIAPI +MicroSecondDelay ( + IN UINTN MicroSeconds + ); + +/** + Stalls the CPU for at least the given number of nanoseconds. + + Stalls the CPU for the number of nanoseconds specified by NanoSeconds. + + @param NanoSeconds The minimum number of nanoseconds to delay. + + @return The value of NanoSeconds inputted. + +**/ +UINTN +EFIAPI +NanoSecondDelay ( + IN UINTN NanoSeconds + ); + +/** + 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(). + + @return The current value of the free running performance counter. + +**/ +UINT64 +EFIAPI +GetPerformanceCounter ( + VOID + ); + +/** + 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. + + @param StartValue The value the performance counter starts with when it + rolls over. + @param EndValue The value that the performance counter ends with before + it rolls over. + + @return The frequency in Hz. + +**/ +UINT64 +EFIAPI +GetPerformanceCounterProperties ( + OUT UINT64 *StartValue, OPTIONAL + OUT UINT64 *EndValue OPTIONAL + ); + +/** + 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. + + @param Ticks The number of elapsed ticks of running performance counter. + + @return The elapsed time in nanoseconds. + +**/ +UINT64 +EFIAPI +GetTimeInNanoSecond ( + IN UINT64 Ticks + ); + +#endif |