1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
|
/** @file
Code for debug timer to support debug agent library implementation.
Copyright (c) 2010 - 2015, 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.
**/
#include "DebugAgent.h"
/**
Initialize CPU local APIC timer.
@param[out] TimerFrequency Local APIC timer frequency returned.
@return 32-bit Local APIC timer init count.
**/
UINT32
InitializeDebugTimer (
OUT UINT32 *TimerFrequency
)
{
UINTN ApicTimerDivisor;
UINT32 InitialCount;
UINT32 ApicTimerFrequency;
GetApicTimerState (&ApicTimerDivisor, NULL, NULL);
ApicTimerFrequency = PcdGet32(PcdFSBClock) / (UINT32)ApicTimerDivisor;
//
// Cpu Local Apic timer interrupt frequency, it is set to 0.1s
//
InitialCount = (UINT32)DivU64x32 (
MultU64x64 (
ApicTimerFrequency,
DEBUG_TIMER_INTERVAL
),
1000000u
);
InitializeApicTimer (ApicTimerDivisor, InitialCount, TRUE, DEBUG_TIMER_VECTOR);
DEBUG ((EFI_D_INFO, "Debug Timer: FSB Clock = %d\n", PcdGet32(PcdFSBClock)));
DEBUG ((EFI_D_INFO, "Debug Timer: Divisor = %d\n", ApicTimerDivisor));
DEBUG ((EFI_D_INFO, "Debug Timer: Frequency = %d\n", ApicTimerFrequency));
DEBUG ((EFI_D_INFO, "Debug Timer: InitialCount = %d\n", InitialCount));
if (TimerFrequency != NULL) {
*TimerFrequency = ApicTimerFrequency;
}
return InitialCount;
}
/**
Enable/Disable the interrupt of debug timer and return the interrupt state
prior to the operation.
If EnableStatus is TRUE, enable the interrupt of debug timer.
If EnableStatus is FALSE, disable the interrupt of debug timer.
@param[in] EnableStatus Enable/Disable.
@retval TRUE Debug timer interrupt were enabled on entry to this call.
@retval FALSE Debug timer interrupt were disabled on entry to this call.
**/
BOOLEAN
EFIAPI
SaveAndSetDebugTimerInterrupt (
IN BOOLEAN EnableStatus
)
{
BOOLEAN OldDebugTimerInterruptState;
OldDebugTimerInterruptState = GetApicTimerInterruptState ();
if (OldDebugTimerInterruptState != EnableStatus) {
if (EnableStatus) {
EnableApicTimerInterrupt ();
} else {
DisableApicTimerInterrupt ();
}
//
// Validate the Debug Timer interrupt state
// This will make additional delay after Local Apic Timer interrupt state is changed.
// Thus, CPU could handle the potential pending interrupt of Local Apic timer.
//
while (GetApicTimerInterruptState () != EnableStatus) {
CpuPause ();
}
}
return OldDebugTimerInterruptState;
}
/**
Check if the timer is time out.
@param[in] TimerCycle Timer total count.
@param[in] Timer The start timer from the begin.
@param[in] TimeoutTicker Ticker number need time out.
@return TRUE Timer time out occurs.
@retval FALSE Timer does not time out.
**/
BOOLEAN
IsDebugTimerTimeout (
IN UINT32 TimerCycle,
IN UINT32 Timer,
IN UINT32 TimeoutTicker
)
{
UINT64 CurrentTimer;
UINT64 Delta;
CurrentTimer = GetApicTimerCurrentCount ();
//
// This timer counter counts down. Check for roll over condition.
//
if (CurrentTimer < Timer) {
Delta = Timer - CurrentTimer;
} else {
//
// Handle one roll-over.
//
Delta = TimerCycle - (CurrentTimer - Timer);
}
return (BOOLEAN) (Delta >= TimeoutTicker);
}
|
