]> git.proxmox.com Git - mirror_edk2.git/blame - MdePkg/Include/Protocol/Timestamp.h
MdeModulePkg: Apply uncrustify changes
[mirror_edk2.git] / MdePkg / Include / Protocol / Timestamp.h
CommitLineData
6a0d41c0 1/** @file\r
9095d37b 2 EFI Timestamp Protocol as defined in UEFI2.4 Specification.\r
6a0d41c0 3 Used to provide a platform independent interface for retrieving a high resolution timestamp counter.\r
9095d37b
LG
4\r
5 Copyright (c) 2013 - 2018, Intel Corporation. All rights reserved.<BR>\r
9344f092 6 SPDX-License-Identifier: BSD-2-Clause-Patent\r
9095d37b
LG
7\r
8 @par Revision Reference:\r
9 This Protocol is introduced in UEFI Specification 2.4\r
10\r
6a0d41c0
SQ
11**/\r
12\r
13#ifndef __EFI_TIME_STAMP_PROTOCOL_H__\r
14#define __EFI_TIME_STAMP_PROTOCOL_H__\r
15\r
16\r
17#define EFI_TIMESTAMP_PROTOCOL_GUID \\r
18 { 0xafbfde41, 0x2e6e, 0x4262, {0xba, 0x65, 0x62, 0xb9, 0x23, 0x6e, 0x54, 0x95 } }\r
19\r
20///\r
21/// Declare forward reference for the Time Stamp Protocol\r
22///\r
23typedef struct _EFI_TIMESTAMP_PROTOCOL EFI_TIMESTAMP_PROTOCOL;\r
24\r
25///\r
26/// EFI_TIMESTAMP_PROPERTIES\r
27///\r
28typedef struct {\r
9095d37b 29 ///\r
6a0d41c0 30 /// The frequency of the timestamp counter in Hz.\r
9095d37b 31 ///\r
6a0d41c0 32 UINT64 Frequency;\r
9095d37b 33 ///\r
6a0d41c0
SQ
34 /// The value that the timestamp counter ends with immediately before it rolls over.\r
35 /// For example, a 64-bit free running counter would have an EndValue of 0xFFFFFFFFFFFFFFFF.\r
36 /// A 24-bit free running counter would have an EndValue of 0xFFFFFF.\r
37 ///\r
38 UINT64 EndValue;\r
39} EFI_TIMESTAMP_PROPERTIES;\r
9095d37b 40\r
6a0d41c0
SQ
41/**\r
42 Retrieves the current value of a 64-bit free running timestamp counter.\r
9095d37b 43\r
6a0d41c0
SQ
44 The counter shall count up in proportion to the amount of time that has passed. The counter value\r
45 will always roll over to zero. The properties of the counter can be retrieved from GetProperties().\r
46 The caller should be prepared for the function to return the same value twice across successive calls.\r
47 The counter value will not go backwards other than when wrapping, as defined by EndValue in GetProperties().\r
9095d37b
LG
48 The frequency of the returned timestamp counter value must remain constant. Power management operations that\r
49 affect clocking must not change the returned counter frequency. The quantization of counter value updates may\r
6a0d41c0
SQ
50 vary as long as the value reflecting time passed remains consistent.\r
51\r
9095d37b 52 @param None.\r
6a0d41c0
SQ
53\r
54 @retval The current value of the free running timestamp counter.\r
55\r
56**/\r
57typedef\r
58UINT64\r
59(EFIAPI *TIMESTAMP_GET)(\r
60 VOID\r
61 );\r
62\r
63/**\r
64 Obtains timestamp counter properties including frequency and value limits.\r
65\r
66 @param[out] Properties The properties of the timestamp counter.\r
67\r
9095d37b
LG
68 @retval EFI_SUCCESS The properties were successfully retrieved.\r
69 @retval EFI_DEVICE_ERROR An error occurred trying to retrieve the properties of the timestamp\r
70 counter subsystem. Properties is not pedated.\r
6a0d41c0
SQ
71 @retval EFI_INVALID_PARAMETER Properties is NULL.\r
72\r
73**/\r
9095d37b 74typedef\r
6a0d41c0
SQ
75EFI_STATUS\r
76(EFIAPI *TIMESTAMP_GET_PROPERTIES)(\r
77 OUT EFI_TIMESTAMP_PROPERTIES *Properties\r
78 );\r
79\r
80\r
81\r
82///\r
83/// EFI_TIMESTAMP_PROTOCOL\r
9095d37b 84/// The protocol provides a platform independent interface for retrieving a high resolution\r
6a0d41c0
SQ
85/// timestamp counter.\r
86///\r
87struct _EFI_TIMESTAMP_PROTOCOL {\r
88 TIMESTAMP_GET GetTimestamp;\r
89 TIMESTAMP_GET_PROPERTIES GetProperties;\r
90};\r
91\r
92extern EFI_GUID gEfiTimestampProtocolGuid;\r
93\r
94#endif\r
95\r