You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
102 lines
3.4 KiB
102 lines
3.4 KiB
/** @file
|
|
EFI Timestamp Protocol as defined in UEFI2.4 Specification.
|
|
Used to provide a platform independent interface for retrieving a high resolution timestamp counter.
|
|
|
|
Copyright (c) 2013 - 2018, 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.
|
|
|
|
@par Revision Reference:
|
|
This Protocol is introduced in UEFI Specification 2.4
|
|
|
|
**/
|
|
|
|
#ifndef __EFI_TIME_STAMP_PROTOCOL_H__
|
|
#define __EFI_TIME_STAMP_PROTOCOL_H__
|
|
|
|
|
|
#define EFI_TIMESTAMP_PROTOCOL_GUID \
|
|
{ 0xafbfde41, 0x2e6e, 0x4262, {0xba, 0x65, 0x62, 0xb9, 0x23, 0x6e, 0x54, 0x95 } }
|
|
|
|
///
|
|
/// Declare forward reference for the Time Stamp Protocol
|
|
///
|
|
typedef struct _EFI_TIMESTAMP_PROTOCOL EFI_TIMESTAMP_PROTOCOL;
|
|
|
|
///
|
|
/// EFI_TIMESTAMP_PROPERTIES
|
|
///
|
|
typedef struct {
|
|
///
|
|
/// The frequency of the timestamp counter in Hz.
|
|
///
|
|
UINT64 Frequency;
|
|
///
|
|
/// The value that the timestamp counter ends with immediately before it rolls over.
|
|
/// For example, a 64-bit free running counter would have an EndValue of 0xFFFFFFFFFFFFFFFF.
|
|
/// A 24-bit free running counter would have an EndValue of 0xFFFFFF.
|
|
///
|
|
UINT64 EndValue;
|
|
} EFI_TIMESTAMP_PROPERTIES;
|
|
|
|
/**
|
|
Retrieves the current value of a 64-bit free running timestamp counter.
|
|
|
|
The counter shall count up in proportion to the amount of time that has passed. The counter value
|
|
will always roll over to zero. The properties of the counter can be retrieved from GetProperties().
|
|
The caller should be prepared for the function to return the same value twice across successive calls.
|
|
The counter value will not go backwards other than when wrapping, as defined by EndValue in GetProperties().
|
|
The frequency of the returned timestamp counter value must remain constant. Power management operations that
|
|
affect clocking must not change the returned counter frequency. The quantization of counter value updates may
|
|
vary as long as the value reflecting time passed remains consistent.
|
|
|
|
@param None.
|
|
|
|
@retval The current value of the free running timestamp counter.
|
|
|
|
**/
|
|
typedef
|
|
UINT64
|
|
(EFIAPI *TIMESTAMP_GET)(
|
|
VOID
|
|
);
|
|
|
|
/**
|
|
Obtains timestamp counter properties including frequency and value limits.
|
|
|
|
@param[out] Properties The properties of the timestamp counter.
|
|
|
|
@retval EFI_SUCCESS The properties were successfully retrieved.
|
|
@retval EFI_DEVICE_ERROR An error occurred trying to retrieve the properties of the timestamp
|
|
counter subsystem. Properties is not pedated.
|
|
@retval EFI_INVALID_PARAMETER Properties is NULL.
|
|
|
|
**/
|
|
typedef
|
|
EFI_STATUS
|
|
(EFIAPI *TIMESTAMP_GET_PROPERTIES)(
|
|
OUT EFI_TIMESTAMP_PROPERTIES *Properties
|
|
);
|
|
|
|
|
|
|
|
///
|
|
/// EFI_TIMESTAMP_PROTOCOL
|
|
/// The protocol provides a platform independent interface for retrieving a high resolution
|
|
/// timestamp counter.
|
|
///
|
|
struct _EFI_TIMESTAMP_PROTOCOL {
|
|
TIMESTAMP_GET GetTimestamp;
|
|
TIMESTAMP_GET_PROPERTIES GetProperties;
|
|
};
|
|
|
|
extern EFI_GUID gEfiTimestampProtocolGuid;
|
|
|
|
#endif
|
|
|