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e1f414b6 1/** @file\r
2 A non-functional instance of the Timer Library.\r
3\r
b9610b9c 4 Copyright (c) 2007 - 2011, Intel Corporation. All rights reserved.<BR>\r
9344f092 5 SPDX-License-Identifier: BSD-2-Clause-Patent\r
e1f414b6 6\r
e1f414b6 7**/\r
8\r
c7d265a9 9#include <Base.h>\r
c7d265a9 10#include <Library/TimerLib.h>\r
11#include <Library/DebugLib.h>\r
e1f414b6 12\r
13/**\r
71871514 14 Stalls the CPU for at least the given number of microseconds.\r
15\r
e1f414b6 16 Stalls the CPU for the number of microseconds specified by MicroSeconds.\r
17\r
18 @param MicroSeconds The minimum number of microseconds to delay.\r
19\r
8cefc2ee 20 @return The value of MicroSeconds inputted.\r
e1f414b6 21\r
22**/\r
23UINTN\r
24EFIAPI\r
25MicroSecondDelay (\r
26 IN UINTN MicroSeconds\r
27 )\r
28{\r
29 ASSERT (FALSE);\r
30 return MicroSeconds;\r
31}\r
32\r
33/**\r
71871514 34 Stalls the CPU for at least the given number of nanoseconds.\r
35\r
e1f414b6 36 Stalls the CPU for the number of nanoseconds specified by NanoSeconds.\r
37\r
38 @param NanoSeconds The minimum number of nanoseconds to delay.\r
39\r
8cefc2ee 40 @return The value of NanoSeconds inputted.\r
e1f414b6 41\r
42**/\r
43UINTN\r
44EFIAPI\r
45NanoSecondDelay (\r
46 IN UINTN NanoSeconds\r
47 )\r
48{\r
49 ASSERT (FALSE);\r
50 return 0;\r
51}\r
52\r
53/**\r
71871514 54 Retrieves the current value of a 64-bit free running performance counter.\r
55\r
56 The counter can either count up by 1 or count down by 1. If the physical\r
e1f414b6 57 performance counter counts by a larger increment, then the counter values\r
58 must be translated. The properties of the counter can be retrieved from\r
59 GetPerformanceCounterProperties().\r
60\r
61 @return The current value of the free running performance counter.\r
62\r
63**/\r
64UINT64\r
65EFIAPI\r
66GetPerformanceCounter (\r
67 VOID\r
68 )\r
69{\r
70 ASSERT (FALSE);\r
71 return 0;\r
72}\r
73\r
74/**\r
75 Retrieves the 64-bit frequency in Hz and the range of performance counter\r
76 values.\r
77\r
78 If StartValue is not NULL, then the value that the performance counter starts\r
79 with immediately after is it rolls over is returned in StartValue. If\r
80 EndValue is not NULL, then the value that the performance counter end with\r
81 immediately before it rolls over is returned in EndValue. The 64-bit\r
82 frequency of the performance counter in Hz is always returned. If StartValue\r
83 is less than EndValue, then the performance counter counts up. If StartValue\r
84 is greater than EndValue, then the performance counter counts down. For\r
85 example, a 64-bit free running counter that counts up would have a StartValue\r
86 of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter\r
87 that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.\r
88\r
89 @param StartValue The value the performance counter starts with when it\r
90 rolls over.\r
91 @param EndValue The value that the performance counter ends with before\r
92 it rolls over.\r
93\r
94 @return The frequency in Hz.\r
95\r
96**/\r
97UINT64\r
98EFIAPI\r
99GetPerformanceCounterProperties (\r
d0e2f823 100 OUT UINT64 *StartValue OPTIONAL,\r
e1f414b6 101 OUT UINT64 *EndValue OPTIONAL\r
102 )\r
103{\r
104 ASSERT (FALSE);\r
e19c2c4a 105\r
106 return (UINT64)(-1);\r
e1f414b6 107}\r
b9610b9c 108\r
109/**\r
110 Converts elapsed ticks of performance counter to time in nanoseconds.\r
111\r
112 This function converts the elapsed ticks of running performance counter to\r
113 time value in unit of nanoseconds.\r
114\r
115 @param Ticks The number of elapsed ticks of running performance counter.\r
116\r
117 @return The elapsed time in nanoseconds.\r
118\r
119**/\r
120UINT64\r
121EFIAPI\r
122GetTimeInNanoSecond (\r
123 IN UINT64 Ticks\r
124 )\r
125{\r
126 ASSERT (FALSE);\r
127 return 0;\r
128}\r