2 Private data structures
4 Copyright (c) 2005 - 2018, Intel Corporation. All rights reserved.<BR>
5 SPDX-License-Identifier: BSD-2-Clause-Patent
13 #include <Protocol/Cpu.h>
14 #include <Protocol/Legacy8259.h>
15 #include <Protocol/Timer.h>
17 #include <Library/UefiBootServicesTableLib.h>
18 #include <Library/BaseLib.h>
19 #include <Library/DebugLib.h>
20 #include <Library/IoLib.h>
23 // The PCAT 8253/8254 has an input clock at 1.193182 MHz and Timer 0 is
24 // initialized as a 16 bit free running counter that generates an interrupt(IRQ0)
25 // each time the counter rolls over.
28 // ---------------- * 1,000,000 uS/S = 54925.4 uS = 549254 * 100 ns
33 // The maximum tick duration for 8254 timer
35 #define MAX_TIMER_TICK_DURATION 549254
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
48 Initialize the Timer Architectural Protocol driver
50 @param ImageHandle ImageHandle of the loaded driver
51 @param SystemTable Pointer to the System Table
53 @retval EFI_SUCCESS Timer Architectural Protocol created
54 @retval EFI_OUT_OF_RESOURCES Not enough resources available to initialize driver.
55 @retval EFI_DEVICE_ERROR A device error occurred attempting to initialize the driver.
60 TimerDriverInitialize (
61 IN EFI_HANDLE ImageHandle
,
62 IN EFI_SYSTEM_TABLE
*SystemTable
68 This function adjusts the period of timer interrupts to the value specified
69 by TimerPeriod. If the timer period is updated, then the selected timer
70 period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If
71 the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
72 If an error occurs while attempting to update the timer period, then the
73 timer hardware will be put back in its state prior to this call, and
74 EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt
75 is disabled. This is not the same as disabling the CPU's interrupts.
76 Instead, it must either turn off the timer hardware, or it must adjust the
77 interrupt controller so that a CPU interrupt is not generated when the timer
81 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
82 @param NotifyFunction The rate to program the timer interrupt in 100 nS units. If
83 the timer hardware is not programmable, then EFI_UNSUPPORTED is
84 returned. If the timer is programmable, then the timer period
85 will be rounded up to the nearest timer period that is supported
86 by the timer hardware. If TimerPeriod is set to 0, then the
87 timer interrupts will be disabled.
89 @retval EFI_SUCCESS The timer period was changed.
90 @retval EFI_UNSUPPORTED The platform cannot change the period of the timer interrupt.
91 @retval EFI_DEVICE_ERROR The timer period could not be changed due to a device error.
96 TimerDriverRegisterHandler (
97 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
98 IN EFI_TIMER_NOTIFY NotifyFunction
104 This function adjusts the period of timer interrupts to the value specified
105 by TimerPeriod. If the timer period is updated, then the selected timer
106 period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If
107 the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
108 If an error occurs while attempting to update the timer period, then the
109 timer hardware will be put back in its state prior to this call, and
110 EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt
111 is disabled. This is not the same as disabling the CPU's interrupts.
112 Instead, it must either turn off the timer hardware, or it must adjust the
113 interrupt controller so that a CPU interrupt is not generated when the timer
117 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
118 @param TimerPeriod The rate to program the timer interrupt in 100 nS units. If
119 the timer hardware is not programmable, then EFI_UNSUPPORTED is
120 returned. If the timer is programmable, then the timer period
121 will be rounded up to the nearest timer period that is supported
122 by the timer hardware. If TimerPeriod is set to 0, then the
123 timer interrupts will be disabled.
125 @retval EFI_SUCCESS The timer period was changed.
126 @retval EFI_UNSUPPORTED The platform cannot change the period of the timer interrupt.
127 @retval EFI_DEVICE_ERROR The timer period could not be changed due to a device error.
132 TimerDriverSetTimerPeriod (
133 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
134 IN UINT64 TimerPeriod
140 This function retrieves the period of timer interrupts in 100 ns units,
141 returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod
142 is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is
143 returned, then the timer is currently disabled.
146 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
147 @param TimerPeriod A pointer to the timer period to retrieve in 100 ns units. If
148 0 is returned, then the timer is currently disabled.
150 @retval EFI_SUCCESS The timer period was returned in TimerPeriod.
151 @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.
156 TimerDriverGetTimerPeriod (
157 IN EFI_TIMER_ARCH_PROTOCOL
*This
,
158 OUT UINT64
*TimerPeriod
164 This function generates a soft timer interrupt. If the platform does not support soft
165 timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.
166 If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()
167 service, then a soft timer interrupt will be generated. If the timer interrupt is
168 enabled when this service is called, then the registered handler will be invoked. The
169 registered handler should not be able to distinguish a hardware-generated timer
170 interrupt from a software-generated timer interrupt.
173 @param This The EFI_TIMER_ARCH_PROTOCOL instance.
175 @retval EFI_SUCCESS The soft timer interrupt was generated.
176 @retval EFI_UNSUPPORTED The platform does not support the generation of soft timer interrupts.
181 TimerDriverGenerateSoftInterrupt (
182 IN EFI_TIMER_ARCH_PROTOCOL
*This