Creating a package for PC/AT chipset drivers and libraries.

[mirror_edk2.git] / DuetPkg / 8254TimerDxe / Timer.h

/*++\r
\r
Copyright (c) 2005 - 2006, Intel Corporation                                                         \r
All rights reserved. This program and the accompanying materials                          \r
are licensed and made available under the terms and conditions of the BSD License         \r
which accompanies this distribution.  The full text of the license may be found at        \r
http://opensource.org/licenses/bsd-license.php                                            \r
                                                                                          \r
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     \r
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.             \r
\r
\r
Module Name:\r
\r
 Timer.h\r
\r
Abstract:\r
\r
  Private data structures\r
\r
--*/\r
\r
#ifndef _TIMER_H_\r
#define _TIMER_H_\r
\r
#include <PiDxe.h>\r
\r
#include <Protocol/Cpu.h>\r
#include <Protocol/Legacy8259.h>\r
#include <Protocol/Timer.h>\r
\r
#include <Library/UefiBootServicesTableLib.h>\r
#include <Library/BaseLib.h>\r
#include <Library/DebugLib.h>\r
#include <Library/IoLib.h>\r
\r
//\r
// The PCAT 8253/8254 has an input clock at 1.193182 MHz and Timer 0 is\r
// initialized as a 16 bit free running counter that generates an interrupt(IRQ0)\r
// each time the counter rolls over.\r
//\r
//   65536 counts\r
// ---------------- * 1,000,000 uS/S = 54925.4 uS = 549254 * 100 ns\r
//   1,193,182 Hz\r
//\r
// The default timer tick duration is set to 10 ms = 100000 100 ns units\r
//\r
#define DEFAULT_TIMER_TICK_DURATION 100000\r
#define TIMER_CONTROL_PORT          0x43\r
#define TIMER0_COUNT_PORT           0x40\r
\r
//\r
// Function Prototypes\r
//\r
EFI_STATUS\r
EFIAPI\r
TimerDriverInitialize (\r
  IN EFI_HANDLE        ImageHandle,\r
  IN EFI_SYSTEM_TABLE  *SystemTable\r
  )\r
/*++\r
\r
Routine Description:\r
\r
  Initialize the Timer Architectural Protocol driver\r
\r
Arguments:\r
\r
  ImageHandle - ImageHandle of the loaded driver\r
\r
  SystemTable - Pointer to the System Table\r
\r
Returns:\r
\r
  EFI_SUCCESS           - Timer Architectural Protocol created\r
\r
  EFI_OUT_OF_RESOURCES  - Not enough resources available to initialize driver.\r
  \r
  EFI_DEVICE_ERROR      - A device error occured attempting to initialize the driver.\r
\r
--*/\r
;\r
\r
EFI_STATUS\r
EFIAPI\r
TimerDriverRegisterHandler (\r
  IN EFI_TIMER_ARCH_PROTOCOL  *This,\r
  IN EFI_TIMER_NOTIFY         NotifyFunction\r
  )\r
/*++\r
\r
Routine Description:\r
\r
  This function registers the handler NotifyFunction so it is called every time \r
  the timer interrupt fires.  It also passes the amount of time since the last \r
  handler call to the NotifyFunction.  If NotifyFunction is NULL, then the \r
  handler is unregistered.  If the handler is registered, then EFI_SUCCESS is \r
  returned.  If the CPU does not support registering a timer interrupt handler, \r
  then EFI_UNSUPPORTED is returned.  If an attempt is made to register a handler \r
  when a handler is already registered, then EFI_ALREADY_STARTED is returned.  \r
  If an attempt is made to unregister a handler when a handler is not registered, \r
  then EFI_INVALID_PARAMETER is returned.  If an error occurs attempting to \r
  register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR \r
  is returned.\r
\r
Arguments:\r
\r
  This           - The EFI_TIMER_ARCH_PROTOCOL instance.\r
\r
  NotifyFunction - The function to call when a timer interrupt fires.  This \r
                   function executes at TPL_HIGH_LEVEL.  The DXE Core will \r
                   register a handler for the timer interrupt, so it can know \r
                   how much time has passed.  This information is used to \r
                   signal timer based events.  NULL will unregister the handler.\r
\r
Returns: \r
\r
  EFI_SUCCESS           - The timer handler was registered.\r
\r
  EFI_UNSUPPORTED       - The platform does not support timer interrupts.\r
\r
  EFI_ALREADY_STARTED   - NotifyFunction is not NULL, and a handler is already \r
                          registered.\r
\r
  EFI_INVALID_PARAMETER - NotifyFunction is NULL, and a handler was not \r
                          previously registered.\r
\r
  EFI_DEVICE_ERROR      - The timer handler could not be registered.\r
\r
--*/\r
;\r
\r
EFI_STATUS\r
EFIAPI\r
TimerDriverSetTimerPeriod (\r
  IN EFI_TIMER_ARCH_PROTOCOL  *This,\r
  IN UINT64                   TimerPeriod\r
  )\r
/*++\r
\r
Routine Description:\r
\r
  This function adjusts the period of timer interrupts to the value specified \r
  by TimerPeriod.  If the timer period is updated, then the selected timer \r
  period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned.  If \r
  the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.  \r
  If an error occurs while attempting to update the timer period, then the \r
  timer hardware will be put back in its state prior to this call, and \r
  EFI_DEVICE_ERROR is returned.  If TimerPeriod is 0, then the timer interrupt \r
  is disabled.  This is not the same as disabling the CPU's interrupts.  \r
  Instead, it must either turn off the timer hardware, or it must adjust the \r
  interrupt controller so that a CPU interrupt is not generated when the timer \r
  interrupt fires. \r
\r
Arguments:\r
\r
  This        - The EFI_TIMER_ARCH_PROTOCOL instance.\r
\r
  TimerPeriod - The rate to program the timer interrupt in 100 nS units.  If \r
                the timer hardware is not programmable, then EFI_UNSUPPORTED is \r
                returned.  If the timer is programmable, then the timer period \r
                will be rounded up to the nearest timer period that is supported \r
                by the timer hardware.  If TimerPeriod is set to 0, then the \r
                timer interrupts will be disabled.\r
\r
Returns: \r
\r
  EFI_SUCCESS      - The timer period was changed.\r
\r
  EFI_UNSUPPORTED  - The platform cannot change the period of the timer interrupt.\r
\r
  EFI_DEVICE_ERROR - The timer period could not be changed due to a device error.\r
\r
--*/\r
;\r
\r
EFI_STATUS\r
EFIAPI\r
TimerDriverGetTimerPeriod (\r
  IN EFI_TIMER_ARCH_PROTOCOL   *This,\r
  OUT UINT64                   *TimerPeriod\r
  )\r
/*++\r
\r
Routine Description:\r
\r
  This function retrieves the period of timer interrupts in 100 ns units, \r
  returns that value in TimerPeriod, and returns EFI_SUCCESS.  If TimerPeriod \r
  is NULL, then EFI_INVALID_PARAMETER is returned.  If a TimerPeriod of 0 is \r
  returned, then the timer is currently disabled.\r
\r
Arguments:\r
\r
  This        - The EFI_TIMER_ARCH_PROTOCOL instance.\r
\r
  TimerPeriod - A pointer to the timer period to retrieve in 100 ns units.  If \r
                0 is returned, then the timer is currently disabled.\r
\r
Returns: \r
\r
  EFI_SUCCESS           - The timer period was returned in TimerPeriod.\r
\r
  EFI_INVALID_PARAMETER - TimerPeriod is NULL.\r
\r
--*/\r
;\r
\r
EFI_STATUS\r
EFIAPI\r
TimerDriverGenerateSoftInterrupt (\r
  IN EFI_TIMER_ARCH_PROTOCOL  *This\r
  )\r
/*++\r
\r
Routine Description:\r
\r
  This function generates a soft timer interrupt. If the platform does not support soft \r
  timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned. \r
  If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler() \r
  service, then a soft timer interrupt will be generated. If the timer interrupt is \r
  enabled when this service is called, then the registered handler will be invoked. The \r
  registered handler should not be able to distinguish a hardware-generated timer \r
  interrupt from a software-generated timer interrupt.\r
\r
Arguments:\r
\r
  This  -  The EFI_TIMER_ARCH_PROTOCOL instance.\r
\r
Returns: \r
\r
  EFI_SUCCESS       - The soft timer interrupt was generated.\r
\r
  EFI_UNSUPPORTEDT  - The platform does not support the generation of soft timer interrupts.\r
\r
--*/\r
;\r
\r
#endif\r