PcAtChipsetPkg/8254TimerDxe/Timer.h

   1 /** @file
   2   Private data structures
   3
   4 Copyright (c) 2005 - 2018, 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
   9
  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.
  12 **/
  13
  14 #ifndef _TIMER_H_
  15 #define _TIMER_H_
  16
  17 #include <PiDxe.h>
  18
  19 #include <Protocol/Cpu.h>
  20 #include <Protocol/Legacy8259.h>
  21 #include <Protocol/Timer.h>
  22
  23 #include <Library/UefiBootServicesTableLib.h>
  24 #include <Library/BaseLib.h>
  25 #include <Library/DebugLib.h>
  26 #include <Library/IoLib.h>
  27
  28 //
  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.
  32 //
  33 //   65536 counts
  34 // ---------------- * 1,000,000 uS/S = 54925.4 uS = 549254 * 100 ns
  35 //   1,193,182 Hz
  36 //
  37
  38 //
  39 // The maximum tick duration for 8254 timer
  40 //
  41 #define MAX_TIMER_TICK_DURATION     549254
  42 //
  43 // The default timer tick duration is set to 10 ms = 100000 100 ns units
  44 //
  45 #define DEFAULT_TIMER_TICK_DURATION 100000
  46 #define TIMER_CONTROL_PORT          0x43
  47 #define TIMER0_COUNT_PORT           0x40
  48
  49 //
  50 // Function Prototypes
  51 //
  52 /**
  53   Initialize the Timer Architectural Protocol driver
  54
  55   @param ImageHandle     ImageHandle of the loaded driver
  56   @param SystemTable     Pointer to the System Table
  57
  58   @retval EFI_SUCCESS            Timer Architectural Protocol created
  59   @retval EFI_OUT_OF_RESOURCES   Not enough resources available to initialize driver.
  60   @retval EFI_DEVICE_ERROR       A device error occurred attempting to initialize the driver.
  61
  62 **/
  63 EFI_STATUS
  64 EFIAPI
  65 TimerDriverInitialize (
  66   IN EFI_HANDLE        ImageHandle,
  67   IN EFI_SYSTEM_TABLE  *SystemTable
  68   )
  69 ;
  70
  71 /**
  72
  73   This function adjusts the period of timer interrupts to the value specified
  74   by TimerPeriod.  If the timer period is updated, then the selected timer
  75   period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned.  If
  76   the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
  77   If an error occurs while attempting to update the timer period, then the
  78   timer hardware will be put back in its state prior to this call, and
  79   EFI_DEVICE_ERROR is returned.  If TimerPeriod is 0, then the timer interrupt
  80   is disabled.  This is not the same as disabling the CPU's interrupts.
  81   Instead, it must either turn off the timer hardware, or it must adjust the
  82   interrupt controller so that a CPU interrupt is not generated when the timer
  83   interrupt fires.
  84
  85
  86   @param This            The EFI_TIMER_ARCH_PROTOCOL instance.
  87   @param NotifyFunction  The rate to program the timer interrupt in 100 nS units.  If
  88                          the timer hardware is not programmable, then EFI_UNSUPPORTED is
  89                          returned.  If the timer is programmable, then the timer period
  90                          will be rounded up to the nearest timer period that is supported
  91                          by the timer hardware.  If TimerPeriod is set to 0, then the
  92                          timer interrupts will be disabled.
  93
  94   @retval        EFI_SUCCESS       The timer period was changed.
  95   @retval        EFI_UNSUPPORTED   The platform cannot change the period of the timer interrupt.
  96   @retval        EFI_DEVICE_ERROR  The timer period could not be changed due to a device error.
  97
  98 **/
  99 EFI_STATUS
 100 EFIAPI
 101 TimerDriverRegisterHandler (
 102   IN EFI_TIMER_ARCH_PROTOCOL  *This,
 103   IN EFI_TIMER_NOTIFY         NotifyFunction
 104   )
 105 ;
 106
 107 /**
 108
 109   This function adjusts the period of timer interrupts to the value specified
 110   by TimerPeriod.  If the timer period is updated, then the selected timer
 111   period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned.  If
 112   the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
 113   If an error occurs while attempting to update the timer period, then the
 114   timer hardware will be put back in its state prior to this call, and
 115   EFI_DEVICE_ERROR is returned.  If TimerPeriod is 0, then the timer interrupt
 116   is disabled.  This is not the same as disabling the CPU's interrupts.
 117   Instead, it must either turn off the timer hardware, or it must adjust the
 118   interrupt controller so that a CPU interrupt is not generated when the timer
 119   interrupt fires.
 120
 121
 122   @param This            The EFI_TIMER_ARCH_PROTOCOL instance.
 123   @param TimerPeriod     The rate to program the timer interrupt in 100 nS units.  If
 124                          the timer hardware is not programmable, then EFI_UNSUPPORTED is
 125                          returned.  If the timer is programmable, then the timer period
 126                          will be rounded up to the nearest timer period that is supported
 127                          by the timer hardware.  If TimerPeriod is set to 0, then the
 128                          timer interrupts will be disabled.
 129
 130   @retval        EFI_SUCCESS       The timer period was changed.
 131   @retval        EFI_UNSUPPORTED   The platform cannot change the period of the timer interrupt.
 132   @retval        EFI_DEVICE_ERROR  The timer period could not be changed due to a device error.
 133
 134 **/
 135 EFI_STATUS
 136 EFIAPI
 137 TimerDriverSetTimerPeriod (
 138   IN EFI_TIMER_ARCH_PROTOCOL  *This,
 139   IN UINT64                   TimerPeriod
 140   )
 141 ;
 142
 143 /**
 144
 145   This function retrieves the period of timer interrupts in 100 ns units,
 146   returns that value in TimerPeriod, and returns EFI_SUCCESS.  If TimerPeriod
 147   is NULL, then EFI_INVALID_PARAMETER is returned.  If a TimerPeriod of 0 is
 148   returned, then the timer is currently disabled.
 149
 150
 151   @param This            The EFI_TIMER_ARCH_PROTOCOL instance.
 152   @param TimerPeriod     A pointer to the timer period to retrieve in 100 ns units.  If
 153                          0 is returned, then the timer is currently disabled.
 154
 155   @retval EFI_SUCCESS            The timer period was returned in TimerPeriod.
 156   @retval EFI_INVALID_PARAMETER  TimerPeriod is NULL.
 157
 158 **/
 159 EFI_STATUS
 160 EFIAPI
 161 TimerDriverGetTimerPeriod (
 162   IN EFI_TIMER_ARCH_PROTOCOL   *This,
 163   OUT UINT64                   *TimerPeriod
 164   )
 165 ;
 166
 167 /**
 168
 169   This function generates a soft timer interrupt. If the platform does not support soft
 170   timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.
 171   If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()
 172   service, then a soft timer interrupt will be generated. If the timer interrupt is
 173   enabled when this service is called, then the registered handler will be invoked. The
 174   registered handler should not be able to distinguish a hardware-generated timer
 175   interrupt from a software-generated timer interrupt.
 176
 177
 178   @param This              The EFI_TIMER_ARCH_PROTOCOL instance.
 179
 180   @retval EFI_SUCCESS       The soft timer interrupt was generated.
 181   @retval EFI_UNSUPPORTED   The platform does not support the generation of soft timer interrupts.
 182
 183 **/
 184 EFI_STATUS
 185 EFIAPI
 186 TimerDriverGenerateSoftInterrupt (
 187   IN EFI_TIMER_ARCH_PROTOCOL  *This
 188   )
 189 ;
 190
 191 #endif