3 Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
5 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.
17 #include <Library/BaseLib.h>
18 #include <Library/TimerLib.h>
19 #include <Library/DebugLib.h>
20 #include <Library/PcdLib.h>
21 #include <Library/IoLib.h>
22 #include <Drivers/SP804Timer.h>
24 #define SP804_TIMER_METRONOME_BASE (UINTN)PcdGet32 (PcdSP804TimerPerformanceBase)
25 #define SP804_TIMER_PERFORMANCE_BASE (UINTN)PcdGet32 (PcdSP804TimerMetronomeBase)
27 // Setup SP810's Timer2 for managing delay functions. And Timer3 for Performance counter
28 // Note: ArmVE's Timer0 and Timer1 are used by TimerDxe.
35 // Check if Timer 2 is already initialized
36 if (MmioRead32(SP804_TIMER_METRONOME_BASE
+ SP804_TIMER_CONTROL_REG
) & SP804_TIMER_CTRL_ENABLE
) {
37 return RETURN_SUCCESS
;
39 // Configure timer 2 for one shot operation, 32 bits, no prescaler, and interrupt disabled
40 MmioOr32 (SP804_TIMER_METRONOME_BASE
+ SP804_TIMER_CONTROL_REG
, SP804_TIMER_CTRL_ONESHOT
| SP804_TIMER_CTRL_32BIT
| SP804_PRESCALE_DIV_1
);
42 // Preload the timer count register
43 MmioWrite32 (SP804_TIMER_METRONOME_BASE
+ SP804_TIMER_LOAD_REG
, 1);
46 MmioOr32 (SP804_TIMER_METRONOME_BASE
+ SP804_TIMER_CONTROL_REG
, SP804_TIMER_CTRL_ENABLE
);
49 // Check if Timer 3 is already initialized
50 if (MmioRead32(SP804_TIMER_PERFORMANCE_BASE
+ SP804_TIMER_CONTROL_REG
) & SP804_TIMER_CTRL_ENABLE
) {
51 return RETURN_SUCCESS
;
53 // Configure timer 3 for free running operation, 32 bits, no prescaler, interrupt disabled
54 MmioOr32 (SP804_TIMER_PERFORMANCE_BASE
+ SP804_TIMER_CONTROL_REG
, SP804_TIMER_CTRL_32BIT
| SP804_PRESCALE_DIV_1
);
57 MmioOr32 (SP804_TIMER_PERFORMANCE_BASE
+ SP804_TIMER_CONTROL_REG
, SP804_TIMER_CTRL_ENABLE
);
60 return RETURN_SUCCESS
;
64 Stalls the CPU for at least the given number of microseconds.
66 Stalls the CPU for the number of microseconds specified by MicroSeconds.
68 @param MicroSeconds The minimum number of microseconds to delay.
70 @return The value of MicroSeconds inputted.
81 // Reload the counter for each 1Mhz to avoid an overflow in the load value
82 for (Index
= 0; Index
< (UINTN
)PcdGet32(PcdSP804TimerFrequencyInMHz
); Index
++) {
83 // load the timer count register
84 MmioWrite32 (SP804_TIMER_METRONOME_BASE
+ SP804_TIMER_LOAD_REG
, MicroSeconds
);
86 while (MmioRead32 (SP804_TIMER_METRONOME_BASE
+ SP804_TIMER_CURRENT_REG
) > 0) {
95 Stalls the CPU for at least the given number of nanoseconds.
97 Stalls the CPU for the number of nanoseconds specified by NanoSeconds.
99 @param NanoSeconds The minimum number of nanoseconds to delay.
101 @return The value of NanoSeconds inputted.
113 // Round up to 1us Tick Number
114 MicroSeconds
= (UINT32
)NanoSeconds
/ 1000;
115 MicroSeconds
+= ((UINT32
)NanoSeconds
% 1000) == 0 ? 0 : 1;
117 // Reload the counter for each 1Mhz to avoid an overflow in the load value
118 for (Index
= 0; Index
< (UINTN
)PcdGet32(PcdSP804TimerFrequencyInMHz
); Index
++) {
119 // load the timer count register
120 MmioWrite32 (SP804_TIMER_METRONOME_BASE
+ SP804_TIMER_LOAD_REG
, MicroSeconds
);
122 while (MmioRead32 (SP804_TIMER_METRONOME_BASE
+ SP804_TIMER_CURRENT_REG
) > 0) {
131 Retrieves the current value of a 64-bit free running performance counter.
133 The counter can either count up by 1 or count down by 1. If the physical
134 performance counter counts by a larger increment, then the counter values
135 must be translated. The properties of the counter can be retrieved from
136 GetPerformanceCounterProperties().
138 @return The current value of the free running performance counter.
143 GetPerformanceCounter (
147 // Free running 64-bit/32-bit counter is needed here.
148 // Don't think we need this to boot, just to do performance profile
150 Value
= MmioRead32 (SP804_TIMER_PERFORMANCE_BASE
+ SP804_TIMER_CURRENT_REG
);
157 Retrieves the 64-bit frequency in Hz and the range of performance counter
160 If StartValue is not NULL, then the value that the performance counter starts
161 with immediately after is it rolls over is returned in StartValue. If
162 EndValue is not NULL, then the value that the performance counter end with
163 immediately before it rolls over is returned in EndValue. The 64-bit
164 frequency of the performance counter in Hz is always returned. If StartValue
165 is less than EndValue, then the performance counter counts up. If StartValue
166 is greater than EndValue, then the performance counter counts down. For
167 example, a 64-bit free running counter that counts up would have a StartValue
168 of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter
169 that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.
171 @param StartValue The value the performance counter starts with when it
173 @param EndValue The value that the performance counter ends with before
176 @return The frequency in Hz.
181 GetPerformanceCounterProperties (
182 OUT UINT64
*StartValue
, OPTIONAL
183 OUT UINT64
*EndValue OPTIONAL
186 if (StartValue
!= NULL
) {
187 // Timer starts with the reload value
188 *StartValue
= 0xFFFFFFFF;
191 if (EndValue
!= NULL
) {
192 // Timer counts down to 0x0
193 *EndValue
= (UINT64
)0ULL;
196 return PcdGet64 (PcdEmbeddedPerformanceCounterFrequencyInHz
);