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git.proxmox.com Git - mirror_edk2.git/blob - MdePkg/Library/SecPeiDxeTimerLibCpu/IpfTimerLib.c
2 Timer Library functions built upon ITC on IPF.
4 Copyright (c) 2006 - 2007, Intel Corporation<BR>
5 All rights reserved. This program and the accompanying materials
6 are licensed and made available under the terms and conditions of the BSD License
7 which accompanies this distribution. The full text of the license may be found at
8 http://opensource.org/licenses/bsd-license.php
10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
16 #include <Library/TimerLib.h>
17 #include <Library/BaseLib.h>
18 #include <Library/IoLib.h>
19 #include <Library/DebugLib.h>
20 #include <Library/PcdLib.h>
24 Performs a delay measured as number of ticks.
26 An internal function to perform a delay measured as number of ticks. It's
27 invoked by MicroSecondDelay() and NanoSecondDelay().
29 @param Delay Number of ticks to delay.
41 // The target timer count is calculated here
43 Ticks
= (INT64
)AsmReadItc () + Delay
;
46 // Wait until time out
47 // Delay > 2^63 could not be handled by this function
48 // Timer wrap-arounds are handled correctly by this function
50 while (Ticks
- (INT64
)AsmReadItc() >= 0);
54 Stalls the CPU for at least the given number of microseconds.
56 Stalls the CPU for the number of microseconds specified by MicroSeconds.
58 @param MicroSeconds The minimum number of microseconds to delay.
70 GetPerformanceCounterProperties (NULL
, NULL
) *
78 Stalls the CPU for at least the given number of nanoseconds.
80 Stalls the CPU for the number of nanoseconds specified by NanoSeconds.
82 @param NanoSeconds The minimum number of nanoseconds to delay.
94 GetPerformanceCounterProperties (NULL
, NULL
) *
102 Retrieves the current value of a 64-bit free running performance counter.
104 Retrieves the current value of a 64-bit free running performance counter. The
105 counter can either count up by 1 or count down by 1. If the physical
106 performance counter counts by a larger increment, then the counter values
107 must be translated. The properties of the counter can be retrieved from
108 GetPerformanceCounterProperties().
110 @return The current value of the free running performance counter.
115 GetPerformanceCounter (
119 return AsmReadItc ();
123 Retrieves the 64-bit frequency in Hz and the range of performance counter
126 If StartValue is not NULL, then the value that the performance counter starts
127 with immediately after is it rolls over is returned in StartValue. If
128 EndValue is not NULL, then the value that the performance counter end with
129 immediately before it rolls over is returned in EndValue. The 64-bit
130 frequency of the performance counter in Hz is always returned. If StartValue
131 is less than EndValue, then the performance counter counts up. If StartValue
132 is greater than EndValue, then the performance counter counts down. For
133 example, a 64-bit free running counter that counts up would have a StartValue
134 of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter
135 that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.
137 @param StartValue The value the performance counter starts with when it
139 @param EndValue The value that the performance counter ends with before
142 @return The frequency in Hz.
147 GetPerformanceCounterProperties (
148 OUT UINT64
*StartValue
, OPTIONAL
149 OUT UINT64
*EndValue OPTIONAL
152 PAL_CALL_RETURN PalRet
;
153 UINT64 BaseFrequence
;
155 PalRet
= PalCallStatic (NULL
, 13, 0, 0, 0);
156 ASSERT (PalRet
.Status
== 0);
157 BaseFrequence
= PalRet
.r9
;
159 PalRet
= PalCallStatic (NULL
, 14, 0, 0, 0);
160 ASSERT (PalRet
.Status
== 0);
162 if (StartValue
!= NULL
) {
166 if (EndValue
!= NULL
) {
167 *EndValue
= (UINT64
)(-1);
170 return BaseFrequence
* (PalRet
.r11
>> 32) / (UINT32
)PalRet
.r11
;