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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.
13 Module Name: IpfTimerLib.c
21 // Include common header file for this module.
23 #include "CommonHeader.h"
26 Performs a delay measured as number of ticks.
28 An internal function to perform a delay measured as number of ticks. It's
29 invoked by MicroSecondDelay() and NanoSecondDelay().
31 @param Delay Number of ticks to delay.
43 // The target timer count is calculated here
45 Ticks
= (INT64
)AsmReadItc () + Delay
;
48 // Wait until time out
49 // Delay > 2^63 could not be handled by this function
50 // Timer wrap-arounds are handled correctly by this function
52 while (Ticks
- (INT64
)AsmReadItc() >= 0);
56 Stalls the CPU for at least the given number of microseconds.
58 Stalls the CPU for the number of microseconds specified by MicroSeconds.
60 @param MicroSeconds The minimum number of microseconds to delay.
72 GetPerformanceCounterProperties (NULL
, NULL
) *
80 Stalls the CPU for at least the given number of nanoseconds.
82 Stalls the CPU for the number of nanoseconds specified by NanoSeconds.
84 @param NanoSeconds The minimum number of nanoseconds to delay.
96 GetPerformanceCounterProperties (NULL
, NULL
) *
104 Retrieves the current value of a 64-bit free running performance counter.
106 Retrieves the current value of a 64-bit free running performance counter. The
107 counter can either count up by 1 or count down by 1. If the physical
108 performance counter counts by a larger increment, then the counter values
109 must be translated. The properties of the counter can be retrieved from
110 GetPerformanceCounterProperties().
112 @return The current value of the free running performance counter.
117 GetPerformanceCounter (
121 return AsmReadItc ();
125 Retrieves the 64-bit frequency in Hz and the range of performance counter
128 If StartValue is not NULL, then the value that the performance counter starts
129 with immediately after is it rolls over is returned in StartValue. If
130 EndValue is not NULL, then the value that the performance counter end with
131 immediately before it rolls over is returned in EndValue. The 64-bit
132 frequency of the performance counter in Hz is always returned. If StartValue
133 is less than EndValue, then the performance counter counts up. If StartValue
134 is greater than EndValue, then the performance counter counts down. For
135 example, a 64-bit free running counter that counts up would have a StartValue
136 of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter
137 that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.
139 @param StartValue The value the performance counter starts with when it
141 @param EndValue The value that the performance counter ends with before
144 @return The frequency in Hz.
149 GetPerformanceCounterProperties (
150 OUT UINT64
*StartValue
, OPTIONAL
151 OUT UINT64
*EndValue OPTIONAL
154 PAL_CALL_RETURN PalRet
;
155 UINT64 BaseFrequence
;
157 PalRet
= PalCallStatic (NULL
, 13, 0, 0, 0);
158 ASSERT (PalRet
.Status
== 0);
159 BaseFrequence
= PalRet
.r9
;
161 PalRet
= PalCallStatic (NULL
, 14, 0, 0, 0);
162 ASSERT (PalRet
.Status
== 0);
164 if (StartValue
!= NULL
) {
168 if (EndValue
!= NULL
) {
169 *EndValue
= (UINT64
)(-1);
172 return BaseFrequence
* (PalRet
.r11
>> 32) / (UINT32
)PalRet
.r11
;