2 Private data structures
4 Copyright (c) 2005 - 2010, Intel Corporation. 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.
19 #include <Protocol/Cpu.h>
20 #include <Protocol/Legacy8259.h>
21 #include <Protocol/Timer.h>
23 #include <Library/UefiBootServicesTableLib.h>
24 #include <Library/BaseLib.h>
25 #include <Library/DebugLib.h>
26 #include <Library/IoLib.h>
29 // The PCAT 8253/8254 has an input clock at 1.193182 MHz and Timer 0 is
30 // initialized as a 16 bit free running counter that generates an interrupt(IRQ0)
31 // each time the counter rolls over.
34 // ---------------- * 1,000,000 uS/S = 54925.4 uS = 549254 * 100 ns
37 // The default timer tick duration is set to 10 ms = 100000 100 ns units
39 #define DEFAULT_TIMER_TICK_DURATION 100000
40 #define TIMER_CONTROL_PORT 0x43
41 #define TIMER0_COUNT_PORT 0x40
44 // Function Prototypes
47 Initialize the Timer Architectural Protocol driver
49 @param ImageHandle ImageHandle of the loaded driver
50 @param SystemTable Pointer to the System Table
52 @retval EFI_SUCCESS Timer Architectural Protocol created
53 @retval EFI_OUT_OF_RESOURCES Not enough resources available to initialize driver.
54 @retval EFI_DEVICE_ERROR A device error occured attempting to initialize the driver.
59 TimerDriverInitialize (
60 IN EFI_HANDLE ImageHandle
,
61 IN EFI_SYSTEM_TABLE
*SystemTable
67 This function adjusts the period of timer interrupts to the value specified
68 by TimerPeriod. If the timer period is updated, then the selected timer
69 period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If
70 the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
71 If an error occurs while attempting to update the timer period, then the
72 timer hardware will be put back in its state prior to this call, and
73 EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt
74 is disabled. This is not the same as disabling the CPU's interrupts.
75 Instead, it must either turn off the timer hardware, or it must adjust the
76 interrupt controller so that a CPU interrupt is not generated when the timer
80 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
81 @param NotifyFunction The rate to program the timer interrupt in 100 nS units. If
82 the timer hardware is not programmable, then EFI_UNSUPPORTED is
83 returned. If the timer is programmable, then the timer period
84 will be rounded up to the nearest timer period that is supported
85 by the timer hardware. If TimerPeriod is set to 0, then the
86 timer interrupts will be disabled.
88 @retval EFI_SUCCESS The timer period was changed.
89 @retval EFI_UNSUPPORTED The platform cannot change the period of the timer interrupt.
90 @retval EFI_DEVICE_ERROR The timer period could not be changed due to a device error.
95 TimerDriverRegisterHandler (
96 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
97 IN EFI_TIMER_NOTIFY NotifyFunction
103 This function adjusts the period of timer interrupts to the value specified
104 by TimerPeriod. If the timer period is updated, then the selected timer
105 period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If
106 the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
107 If an error occurs while attempting to update the timer period, then the
108 timer hardware will be put back in its state prior to this call, and
109 EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt
110 is disabled. This is not the same as disabling the CPU's interrupts.
111 Instead, it must either turn off the timer hardware, or it must adjust the
112 interrupt controller so that a CPU interrupt is not generated when the timer
116 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
117 @param TimerPeriod The rate to program the timer interrupt in 100 nS units. If
118 the timer hardware is not programmable, then EFI_UNSUPPORTED is
119 returned. If the timer is programmable, then the timer period
120 will be rounded up to the nearest timer period that is supported
121 by the timer hardware. If TimerPeriod is set to 0, then the
122 timer interrupts will be disabled.
124 @retval EFI_SUCCESS The timer period was changed.
125 @retval EFI_UNSUPPORTED The platform cannot change the period of the timer interrupt.
126 @retval EFI_DEVICE_ERROR The timer period could not be changed due to a device error.
131 TimerDriverSetTimerPeriod (
132 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
133 IN UINT64 TimerPeriod
139 This function retrieves the period of timer interrupts in 100 ns units,
140 returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod
141 is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is
142 returned, then the timer is currently disabled.
145 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
146 @param TimerPeriod A pointer to the timer period to retrieve in 100 ns units. If
147 0 is returned, then the timer is currently disabled.
149 @retval EFI_SUCCESS The timer period was returned in TimerPeriod.
150 @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.
155 TimerDriverGetTimerPeriod (
156 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
157 OUT UINT64
*TimerPeriod
163 This function generates a soft timer interrupt. If the platform does not support soft
164 timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.
165 If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()
166 service, then a soft timer interrupt will be generated. If the timer interrupt is
167 enabled when this service is called, then the registered handler will be invoked. The
168 registered handler should not be able to distinguish a hardware-generated timer
169 interrupt from a software-generated timer interrupt.
172 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
174 @retval EFI_SUCCESS The soft timer interrupt was generated.
175 @retval EFI_UNSUPPORTEDT The platform does not support the generation of soft timer interrupts.
180 TimerDriverGenerateSoftInterrupt (
181 IN EFI_TIMER_ARCH_PROTOCOL
*This