diff --git a/MdeModulePkg/Universal/Metronome/Metronome.c b/MdeModulePkg/Universal/Metronome/Metronome.c new file mode 100644 index 0000000000..8a84964ba1 --- /dev/null +++ b/MdeModulePkg/Universal/Metronome/Metronome.c @@ -0,0 +1,141 @@ +/*++ + +Copyright (c) 2005, Intel Corporation +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. + +Module Name: + + Metronome.c + +Abstract: + + This is a generic implementation of the Metronome Architectural Protocol that + layers on top of an instance of the Timer Library. The Timer Library provides + functions for nanosecond and microsecond delays. This generic implementation + produces a fixed TickPeriod of 1 100ns unit, and when the WaitForTick() service + is called, the number of ticks passed in is converted to either nanosecond or + microsecond units. If the number of ticks is small, then nanoseconds are used. + If the number of ticks is large, then microseconds are used. This prevents + overflows that could occur for long delays if only nanoseconds were used and also + provides the greatest accuracy for small delays. + +--*/ + +#include +#include +#include +#include +#include + +// +// Function Prototypes +// +EFI_STATUS +EFIAPI +WaitForTick ( + IN EFI_METRONOME_ARCH_PROTOCOL *This, + IN UINT32 TickNumber + ); + +// +// Handle for the Metronome Architectural Protocol instance produced by this driver +// +EFI_HANDLE mMetronomeHandle = NULL; + +// +// The Metronome Architectural Protocol instance produced by this driver +// +EFI_METRONOME_ARCH_PROTOCOL mMetronome = { + WaitForTick, + 1 // TickPeriod = 1*100 ns units +}; + +/** + The WaitForTick() function waits for the number of ticks specified by + TickNumber from a known time source in the platform. If TickNumber of + ticks are detected, then EFI_SUCCESS is returned. The actual time passed + between entry of this function and the first tick is between 0 and + TickPeriod 100 nS units. If you want to guarantee that at least TickPeriod + time has elapsed, wait for two ticks. This function waits for a hardware + event to determine when a tick occurs. It is possible for interrupt + processing, or exception processing to interrupt the execution of the + WaitForTick() function. Depending on the hardware source for the ticks, it + is possible for a tick to be missed. This function cannot guarantee that + ticks will not be missed. If a timeout occurs waiting for the specified + number of ticks, then EFI_TIMEOUT is returned. + + @param This The EFI_METRONOME_ARCH_PROTOCOL instance. + @param TickNumber Number of ticks to wait. + + @retval EFI_SUCCESS The wait for the number of ticks specified by TickNumber + succeeded. + @retval EFI_TIMEOUT A timeout occurred waiting for the specified number of ticks. + +**/ +EFI_STATUS +EFIAPI +WaitForTick ( + IN EFI_METRONOME_ARCH_PROTOCOL *This, + IN UINT32 TickNumber + ) +{ + // + // Check the value of TickNumber, so a 32-bit overflow can be avoided + // when TickNumber of converted to nanosecond units + // + if (TickNumber < 10000000) { + // + // If TickNumber is small, then use NanoSecondDelay() + // + NanoSecondDelay (TickNumber * 100); + } else { + // + // If TickNumber is large, then use MicroSecondDelay() + // + MicroSecondDelay (TickNumber / 10); + } + return EFI_SUCCESS; +} + +/** + The user Entry Point for module Metronome. The user code starts with this function. + + @param[in] ImageHandle The firmware allocated handle for the EFI image. + @param[in] SystemTable A pointer to the EFI System Table. + + @retval EFI_SUCCESS The entry point is executed successfully. + @retval other Some error occurs when executing this entry point. + +**/ +EFI_STATUS +EFIAPI +InstallMetronome ( + IN EFI_HANDLE ImageHandle, + IN EFI_SYSTEM_TABLE *SystemTable + ) +{ + EFI_STATUS Status; + + // + // Make sure the Metronome Architectural Protocol is not already installed in the system + // + ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiMetronomeArchProtocolGuid); + + // + // Install on a new handle + // + Status = gBS->InstallMultipleProtocolInterfaces ( + &mMetronomeHandle, + &gEfiMetronomeArchProtocolGuid, &mMetronome, + NULL + ); + ASSERT_EFI_ERROR (Status); + + return Status; +} diff --git a/MdeModulePkg/Universal/Metronome/Metronome.inf b/MdeModulePkg/Universal/Metronome/Metronome.inf new file mode 100644 index 0000000000..fbb9b8b80a --- /dev/null +++ b/MdeModulePkg/Universal/Metronome/Metronome.inf @@ -0,0 +1,44 @@ +#/*++ +# +# Copyright (c) 2005, Intel Corporation +# 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. +# +# Module Name: +# +# Abstract: +# +#--*/ + +[Defines] + INF_VERSION = 0x00010005 + BASE_NAME = Metronome + FILE_GUID = C8339973-A563-4561-B858-D8476F9DEFC4 + MODULE_TYPE = DXE_DRIVER + VERSION_STRING = 1.0 + EDK_RELEASE_VERSION = 0x00020000 + EFI_SPECIFICATION_VERSION = 0x00020000 + ENTRY_POINT = InstallMetronome + +[Packages] + MdePkg/MdePkg.dec + +[LibraryClasses] + UefiDriverEntryPoint + UefiBootServicesTableLib + TimerLib + DebugLib + +[Sources.common] + Metronome.c + +[Protocols] + gEfiMetronomeArchProtocolGuid + +[Depex] + TRUE