/** @file
  Copyright (c) 2006, Intel Corporation
  All rights reserved. This program and the accompanying materials
  are licensed and made available under the terms and conditions of the BSD License
  which accompanies this distribution.  The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.php

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#include "idebus.h"

BOOLEAN ChannelDeviceDetected = FALSE;
BOOLEAN SlaveDeviceExist      = FALSE;
UINT8   SlaveDeviceType       = INVALID_DEVICE_TYPE;
BOOLEAN MasterDeviceExist     = FALSE;
UINT8   MasterDeviceType      = INVALID_DEVICE_TYPE;

/**
  TODO: Add function description

  @param  PciIo TODO: add argument description
  @param  Port TODO: add argument description

  TODO: add return values

**/
UINT8
IDEReadPortB (
  IN  EFI_PCI_IO_PROTOCOL   *PciIo,
  IN  UINT16                Port
  )
{
  UINT8 Data;

  Data = 0;
  //
  // perform 1-byte data read from register
  //
  PciIo->Io.Read (
              PciIo,
              EfiPciIoWidthUint8,
              EFI_PCI_IO_PASS_THROUGH_BAR,
              (UINT64) Port,
              1,
              &Data
              );
  return Data;
}

/**
  Reads multiple words of data from the IDE data port.
  Call the IO abstraction once to do the complete read,
  not one word at a time

  @param  PciIo Pointer to the EFI_PCI_IO instance
  @param  Port IO port to read
  @param  Count No. of UINT16's to read
  @param  Buffer Pointer to the data buffer for read

**/
VOID
IDEReadPortWMultiple (
  IN  EFI_PCI_IO_PROTOCOL   *PciIo,
  IN  UINT16                Port,
  IN  UINTN                 Count,
  IN  VOID                  *Buffer
  )
{
  UINT16  *AlignedBuffer;
  UINT16  *WorkingBuffer;
  UINTN   Size;

  //
  // Prepare an 16-bit alligned working buffer. CpuIo will return failure and
  // not perform actual I/O operations if buffer pointer passed in is not at
  // natural boundary. The "Buffer" argument is passed in by user and may not
  // at 16-bit natural boundary.
  //
  Size = sizeof (UINT16) * Count;

  gBS->AllocatePool (
        EfiBootServicesData,
        Size + 1,
        (VOID**)&WorkingBuffer
        );

  AlignedBuffer = (UINT16 *) ((UINTN)(((UINTN) WorkingBuffer + 0x1) & (~0x1)));

  //
  // Perform UINT16 data read from FIFO
  //
  PciIo->Io.Read (
              PciIo,
              EfiPciIoWidthFifoUint16,
              EFI_PCI_IO_PASS_THROUGH_BAR,
              (UINT64) Port,
              Count,
              (UINT16*)AlignedBuffer
              );

  //
  // Copy data to user buffer
  //
  CopyMem (Buffer, (UINT16*)AlignedBuffer, Size);
  gBS->FreePool (WorkingBuffer);
}

/**
  TODO: Add function description

  @param  PciIo TODO: add argument description
  @param  Port TODO: add argument description
  @param  Data TODO: add argument description

  TODO: add return values

**/
VOID
IDEWritePortB (
  IN  EFI_PCI_IO_PROTOCOL   *PciIo,
  IN  UINT16                Port,
  IN  UINT8                 Data
  )
{
  //
  // perform 1-byte data write to register
  //
  PciIo->Io.Write (
              PciIo,
              EfiPciIoWidthUint8,
              EFI_PCI_IO_PASS_THROUGH_BAR,
              (UINT64) Port,
              1,
              &Data
              );

}

/**
  TODO: Add function description

  @param  PciIo TODO: add argument description
  @param  Port TODO: add argument description
  @param  Data TODO: add argument description

  TODO: add return values

**/
VOID
IDEWritePortW (
  IN  EFI_PCI_IO_PROTOCOL   *PciIo,
  IN  UINT16                Port,
  IN  UINT16                Data
  )
{
  //
  // perform 1-word data write to register
  //
  PciIo->Io.Write (
              PciIo,
              EfiPciIoWidthUint16,
              EFI_PCI_IO_PASS_THROUGH_BAR,
              (UINT64) Port,
              1,
              &Data
              );
}

/**
  Write multiple words of data to the IDE data port.
  Call the IO abstraction once to do the complete read,
  not one word at a time

  @param  PciIo Pointer to the EFI_PCI_IO instance
  @param  Port IO port to read
  @param  Count No. of UINT16's to read
  @param  Buffer Pointer to the data buffer for read

**/
VOID
IDEWritePortWMultiple (
  IN  EFI_PCI_IO_PROTOCOL   *PciIo,
  IN  UINT16                Port,
  IN  UINTN                 Count,
  IN  VOID                  *Buffer
  )
{
  UINT16  *AlignedBuffer;
  UINT32  *WorkingBuffer;
  UINTN   Size;

  //
  // Prepare an 16-bit alligned working buffer. CpuIo will return failure and
  // not perform actual I/O operations if buffer pointer passed in is not at
  // natural boundary. The "Buffer" argument is passed in by user and may not
  // at 16-bit natural boundary.
  //
  Size = sizeof (UINT16) * Count;

  gBS->AllocatePool (
        EfiBootServicesData,
        Size + 1,
        (VOID **) &WorkingBuffer
        );

  AlignedBuffer = (UINT16 *) ((UINTN)(((UINTN) WorkingBuffer + 0x1) & (~0x1)));

  //
  // Copy data from user buffer to working buffer
  //
  CopyMem ((UINT16 *) AlignedBuffer, Buffer, Size);

  //
  // perform UINT16 data write to the FIFO
  //
  PciIo->Io.Write (
              PciIo,
              EfiPciIoWidthFifoUint16,
              EFI_PCI_IO_PASS_THROUGH_BAR,
              (UINT64) Port,
              Count,
              (UINT16 *) AlignedBuffer
              );

  gBS->FreePool (WorkingBuffer);
}

//
// GetIdeRegistersBaseAddr
//
/**
  Get IDE IO port registers' base addresses by mode. In 'Compatibility' mode,
  use fixed addresses. In Native-PCI mode, get base addresses from BARs in
  the PCI IDE controller's Configuration Space.

  The steps to get IDE IO port registers' base addresses for each channel
  as follows:

  1. Examine the Programming Interface byte of the Class Code fields in PCI IDE
  controller's Configuration Space to determine the operating mode.

  2. a) In 'Compatibility' mode, use fixed addresses shown in the Table 1 below.
  <pre>
  ___________________________________________
  |           | Command Block | Control Block |
  |  Channel  |   Registers   |   Registers   |
  |___________|_______________|_______________|
  |  Primary  |  1F0h - 1F7h  |  3F6h - 3F7h  |
  |___________|_______________|_______________|
  | Secondary |  170h - 177h  |  376h - 377h  |
  |___________|_______________|_______________|

  Table 1. Compatibility resource mappings
  </pre>

  b) In Native-PCI mode, IDE registers are mapped into IO space using the BARs
  in IDE controller's PCI Configuration Space, shown in the Table 2 below.
  <pre>
  ___________________________________________________
  |           |   Command Block   |   Control Block   |
  |  Channel  |     Registers     |     Registers     |
  |___________|___________________|___________________|
  |  Primary  | BAR at offset 0x10| BAR at offset 0x14|
  |___________|___________________|___________________|
  | Secondary | BAR at offset 0x18| BAR at offset 0x1C|
  |___________|___________________|___________________|

  Table 2. BARs for Register Mapping
  </pre>
  @note Refer to Intel ICH4 datasheet, Control Block Offset: 03F4h for
  primary, 0374h for secondary. So 2 bytes extra offset should be
  added to the base addresses read from BARs.

  For more details, please refer to PCI IDE Controller Specification and Intel
  ICH4 Datasheet.

  @param  PciIo Pointer to the EFI_PCI_IO_PROTOCOL instance
  @param  IdeRegsBaseAddr Pointer to IDE_REGISTERS_BASE_ADDR to
  receive IDE IO port registers' base addresses

**/
EFI_STATUS
GetIdeRegistersBaseAddr (
  IN  EFI_PCI_IO_PROTOCOL         *PciIo,
  OUT IDE_REGISTERS_BASE_ADDR     *IdeRegsBaseAddr
  )
// TODO:    EFI_UNSUPPORTED - add return value to function comment
// TODO:    EFI_UNSUPPORTED - add return value to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  EFI_STATUS  Status;
  PCI_TYPE00  PciData;

  Status = PciIo->Pci.Read (
                        PciIo,
                        EfiPciIoWidthUint8,
                        0,
                        sizeof (PciData),
                        &PciData
                        );

  if (EFI_ERROR (Status)) {
    return Status;
  }

  if ((PciData.Hdr.ClassCode[0] & IDE_PRIMARY_OPERATING_MODE) == 0) {
    IdeRegsBaseAddr[IdePrimary].CommandBlockBaseAddr  = 0x1f0;
    IdeRegsBaseAddr[IdePrimary].ControlBlockBaseAddr  = 0x3f6;
    IdeRegsBaseAddr[IdePrimary].BusMasterBaseAddr     =
    (UINT16)((PciData.Device.Bar[4] & 0x0000fff0));
  } else {
    //
    // The BARs should be of IO type
    //
    if ((PciData.Device.Bar[0] & bit0) == 0 ||
        (PciData.Device.Bar[1] & bit0) == 0) {
      return EFI_UNSUPPORTED;
    }

    IdeRegsBaseAddr[IdePrimary].CommandBlockBaseAddr  =
    (UINT16) (PciData.Device.Bar[0] & 0x0000fff8);
    IdeRegsBaseAddr[IdePrimary].ControlBlockBaseAddr  =
    (UINT16) ((PciData.Device.Bar[1] & 0x0000fffc) + 2);
    IdeRegsBaseAddr[IdePrimary].BusMasterBaseAddr     =
    (UINT16) ((PciData.Device.Bar[4] & 0x0000fff0));
  }

  if ((PciData.Hdr.ClassCode[0] & IDE_SECONDARY_OPERATING_MODE) == 0) {
    IdeRegsBaseAddr[IdeSecondary].CommandBlockBaseAddr  = 0x170;
    IdeRegsBaseAddr[IdeSecondary].ControlBlockBaseAddr  = 0x376;
    IdeRegsBaseAddr[IdeSecondary].BusMasterBaseAddr     =
    (UINT16) ((PciData.Device.Bar[4] & 0x0000fff0));
  } else {
    //
    // The BARs should be of IO type
    //
    if ((PciData.Device.Bar[2] & bit0) == 0 ||
        (PciData.Device.Bar[3] & bit0) == 0) {
      return EFI_UNSUPPORTED;
    }

    IdeRegsBaseAddr[IdeSecondary].CommandBlockBaseAddr  =
    (UINT16) (PciData.Device.Bar[2] & 0x0000fff8);
    IdeRegsBaseAddr[IdeSecondary].ControlBlockBaseAddr  =
    (UINT16) ((PciData.Device.Bar[3] & 0x0000fffc) + 2);
    IdeRegsBaseAddr[IdeSecondary].BusMasterBaseAddr     =
    (UINT16) ((PciData.Device.Bar[4] & 0x0000fff0));
  }

  return EFI_SUCCESS;
}

/**
  This function is used to requery IDE resources. The IDE controller will
  probably switch between native and legacy modes during the EFI->CSM->OS
  transfer. We do this everytime before an BlkIo operation to ensure its
  succeess.

  @param  IdeDev The BLK_IO private data which specifies the IDE device

**/
EFI_STATUS
ReassignIdeResources (
  IN  IDE_BLK_IO_DEV  *IdeDev
  )
// TODO:    EFI_SUCCESS - add return value to function comment
{
  EFI_STATUS              Status;
  IDE_REGISTERS_BASE_ADDR IdeRegsBaseAddr[IdeMaxChannel];
  UINT16                  CommandBlockBaseAddr;
  UINT16                  ControlBlockBaseAddr;

  //
  // Requery IDE IO port registers' base addresses in case of the switch of
  // native and legacy modes
  //
  Status = GetIdeRegistersBaseAddr (IdeDev->PciIo, IdeRegsBaseAddr);
  if (EFI_ERROR (Status)) {
    return Status;
  }

  ZeroMem (IdeDev->IoPort, sizeof (IDE_BASE_REGISTERS));
  CommandBlockBaseAddr                = IdeRegsBaseAddr[IdeDev->Channel].CommandBlockBaseAddr;
  ControlBlockBaseAddr                = IdeRegsBaseAddr[IdeDev->Channel].ControlBlockBaseAddr;

  IdeDev->IoPort->Data                = CommandBlockBaseAddr;
  (*(UINT16 *) &IdeDev->IoPort->Reg1) = (UINT16) (CommandBlockBaseAddr + 0x01);
  IdeDev->IoPort->SectorCount         = (UINT16) (CommandBlockBaseAddr + 0x02);
  IdeDev->IoPort->SectorNumber        = (UINT16) (CommandBlockBaseAddr + 0x03);
  IdeDev->IoPort->CylinderLsb         = (UINT16) (CommandBlockBaseAddr + 0x04);
  IdeDev->IoPort->CylinderMsb         = (UINT16) (CommandBlockBaseAddr + 0x05);
  IdeDev->IoPort->Head                = (UINT16) (CommandBlockBaseAddr + 0x06);

  (*(UINT16 *) &IdeDev->IoPort->Reg)  = (UINT16) (CommandBlockBaseAddr + 0x07);
  (*(UINT16 *) &IdeDev->IoPort->Alt)  = ControlBlockBaseAddr;
  IdeDev->IoPort->DriveAddress        = (UINT16) (ControlBlockBaseAddr + 0x01);
  IdeDev->IoPort->MasterSlave         = (UINT16) ((IdeDev->Device == IdeMaster) ? 1 : 0);

  IdeDev->IoPort->BusMasterBaseAddr   = IdeRegsBaseAddr[IdeDev->Channel].BusMasterBaseAddr;
  return EFI_SUCCESS;
}

//
// DiscoverIdeDevice
//
/**
  Detect if there is disk connected to this port

  @param  IdeDev The BLK_IO private data which specifies the IDE device

**/
EFI_STATUS
DiscoverIdeDevice (
  IN IDE_BLK_IO_DEV *IdeDev
  )
// TODO:    EFI_NOT_FOUND - add return value to function comment
// TODO:    EFI_NOT_FOUND - add return value to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  EFI_STATUS  Status;

  //
  // If a channel has not been checked, check it now. Then set it to "checked" state
  // After this step, all devices in this channel have been checked.
  //
  if (ChannelDeviceDetected == FALSE) {
    Status = DetectIDEController (IdeDev);
    if (EFI_ERROR (Status)) {
      return EFI_NOT_FOUND;
    }
  }

  Status = EFI_NOT_FOUND;

  //
  // Device exists. test if it is an ATA device.
  // Prefer the result from DetectIDEController,
  // if failed, try another device type to handle
  // devices that not follow the spec.
  //
  if ((IdeDev->Device == IdeMaster) && (MasterDeviceExist)) {
    if (MasterDeviceType == ATA_DEVICE_TYPE) {
      Status = ATAIdentify (IdeDev);
      if (EFI_ERROR (Status)) {
        Status = ATAPIIdentify (IdeDev);
        if (!EFI_ERROR (Status)) {
          MasterDeviceType = ATAPI_DEVICE_TYPE;
        }
      }
    } else {
      Status = ATAPIIdentify (IdeDev);
      if (EFI_ERROR (Status)) {
        Status = ATAIdentify (IdeDev);
        if (!EFI_ERROR (Status)) {
          MasterDeviceType = ATA_DEVICE_TYPE;
        }
      }
    }
  }
  if ((IdeDev->Device == IdeSlave) && (SlaveDeviceExist)) {
    if (SlaveDeviceType == ATA_DEVICE_TYPE) {
      Status = ATAIdentify (IdeDev);
      if (EFI_ERROR (Status)) {
        Status = ATAPIIdentify (IdeDev);
        if (!EFI_ERROR (Status)) {
          SlaveDeviceType = ATAPI_DEVICE_TYPE;
        }
      }
    } else {
      Status = ATAPIIdentify (IdeDev);
      if (EFI_ERROR (Status)) {
        Status = ATAIdentify (IdeDev);
        if (!EFI_ERROR (Status)) {
          SlaveDeviceType = ATA_DEVICE_TYPE;
        }
      }
    }
  }
  if (EFI_ERROR (Status)) {
    return EFI_NOT_FOUND;
  }
  //
  // Init Block I/O interface
  //
  IdeDev->BlkIo.Revision            = EFI_BLOCK_IO_PROTOCOL_REVISION;
  IdeDev->BlkIo.Reset               = IDEBlkIoReset;
  IdeDev->BlkIo.ReadBlocks          = IDEBlkIoReadBlocks;
  IdeDev->BlkIo.WriteBlocks         = IDEBlkIoWriteBlocks;
  IdeDev->BlkIo.FlushBlocks         = IDEBlkIoFlushBlocks;

  IdeDev->BlkMedia.LogicalPartition = FALSE;
  IdeDev->BlkMedia.WriteCaching     = FALSE;

  //
  // Init Disk Info interface
  //
  gBS->CopyMem (&IdeDev->DiskInfo.Interface, &gEfiDiskInfoIdeInterfaceGuid, sizeof (EFI_GUID));
  IdeDev->DiskInfo.Inquiry    = IDEDiskInfoInquiry;
  IdeDev->DiskInfo.Identify   = IDEDiskInfoIdentify;
  IdeDev->DiskInfo.SenseData  = IDEDiskInfoSenseData;
  IdeDev->DiskInfo.WhichIde   = IDEDiskInfoWhichIde;

  return EFI_SUCCESS;
}

/**
  This interface is used to initialize all state data related to the detection of one
  channel.

  @retval EFI_SUCCESS Completed Successfully.

**/
EFI_STATUS
InitializeIDEChannelData (
  VOID
  )
{
  ChannelDeviceDetected = FALSE;
  MasterDeviceExist = FALSE;
  MasterDeviceType  = 0xff;
  SlaveDeviceExist  = FALSE;
  SlaveDeviceType   = 0xff;
  return EFI_SUCCESS;
}

/**
  This function is called by DiscoverIdeDevice(). It is used for detect
  whether the IDE device exists in the specified Channel as the specified
  Device Number.

  There is two IDE channels: one is Primary Channel, the other is
  Secondary Channel.(Channel is the logical name for the physical "Cable".)
  Different channel has different register group.

  On each IDE channel, at most two IDE devices attach,
  one is called Device 0 (Master device), the other is called Device 1
  (Slave device). The devices on the same channel co-use the same register
  group, so before sending out a command for a specified device via command
  register, it is a must to select the current device to accept the command
  by set the device number in the Head/Device Register.

  @param[in] *IdeDev
  pointer pointing to IDE_BLK_IO_DEV data structure, used
  to record all the information of the IDE device.

  @retval TRUE
  successfully detects device.

  @retval FALSE
  any failure during detection process will return this
  value.

  @note
  TODO:    EFI_SUCCESS - add return value to function comment
  TODO:    EFI_NOT_FOUND - add return value to function comment

**/
EFI_STATUS
DetectIDEController (
  IN  IDE_BLK_IO_DEV  *IdeDev
  )
{
  EFI_STATUS  Status;
  UINT8       SectorCountReg;
  UINT8       LBALowReg;
  UINT8       LBAMidReg;
  UINT8       LBAHighReg;
  UINT8       InitStatusReg;
  UINT8       StatusReg;

  //
  // Select slave device
  //
  IDEWritePortB (
    IdeDev->PciIo,
    IdeDev->IoPort->Head,
    (UINT8) ((1 << 4) | 0xe0)
    );
  gBS->Stall (100);

  //
  // Save the init slave status register
  //
  InitStatusReg = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Reg.Status);

  //
  // Select Master back
  //
  IDEWritePortB (
    IdeDev->PciIo,
    IdeDev->IoPort->Head,
    (UINT8) ((0 << 4) | 0xe0)
    );
  gBS->Stall (100);

  //
  // Send ATA Device Execut Diagnostic command.
  // This command should work no matter DRDY is ready or not
  //
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->Reg.Command, 0x90);

  Status    = WaitForBSYClear (IdeDev, 3500);
  if (EFI_ERROR (Status)) {
    DEBUG((EFI_D_ERROR, "New detecting method: Send Execute Diagnostic Command: WaitForBSYClear: Status: %d\n", Status));
    return Status;
  }
  //
  // Read device signature
  //
  //
  // Select Master
  //
  IDEWritePortB (
    IdeDev->PciIo,
    IdeDev->IoPort->Head,
    (UINT8) ((0 << 4) | 0xe0)
    );
  gBS->Stall (100);
  SectorCountReg = IDEReadPortB (
                     IdeDev->PciIo,
                     IdeDev->IoPort->SectorCount
                     );
  LBALowReg      = IDEReadPortB (
                     IdeDev->PciIo,
                     IdeDev->IoPort->SectorNumber
                     );
  LBAMidReg      = IDEReadPortB (
                     IdeDev->PciIo,
                     IdeDev->IoPort->CylinderLsb
                     );
  LBAHighReg     = IDEReadPortB (
                     IdeDev->PciIo,
                     IdeDev->IoPort->CylinderMsb
                     );
  if ((SectorCountReg == 0x1) &&
      (LBALowReg      == 0x1) &&
      (LBAMidReg      == 0x0) &&
      (LBAHighReg     == 0x0)) {
    MasterDeviceExist = TRUE;
    MasterDeviceType  = ATA_DEVICE_TYPE;
  } else {
    if ((LBAMidReg      == 0x14) &&
        (LBAHighReg     == 0xeb)) {
      MasterDeviceExist = TRUE;
      MasterDeviceType  = ATAPI_DEVICE_TYPE;
    }
  }

  //
  // For some Hard Drive, it takes some time to get
  // the right signature when operating in single slave mode.
  // We stall 20ms to work around this.
  //
  if (!MasterDeviceExist) {
    gBS->Stall (20000);
  }

  //
  // Select Slave
  //
  IDEWritePortB (
    IdeDev->PciIo,
    IdeDev->IoPort->Head,
    (UINT8) ((1 << 4) | 0xe0)
    );
  gBS->Stall (100);
  SectorCountReg = IDEReadPortB (
                     IdeDev->PciIo,
                     IdeDev->IoPort->SectorCount
                     );
  LBALowReg  = IDEReadPortB (
                 IdeDev->PciIo,
                 IdeDev->IoPort->SectorNumber
                 );
  LBAMidReg  = IDEReadPortB (
                 IdeDev->PciIo,
                 IdeDev->IoPort->CylinderLsb
                 );
  LBAHighReg = IDEReadPortB (
                 IdeDev->PciIo,
                 IdeDev->IoPort->CylinderMsb
                 );
  StatusReg  = IDEReadPortB (
                 IdeDev->PciIo,
                 IdeDev->IoPort->Reg.Status
                 );
  if ((SectorCountReg == 0x1) &&
      (LBALowReg      == 0x1) &&
      (LBAMidReg      == 0x0) &&
      (LBAHighReg     == 0x0)) {
    SlaveDeviceExist = TRUE;
    SlaveDeviceType  = ATA_DEVICE_TYPE;
  } else {
    if ((LBAMidReg     == 0x14) &&
        (LBAHighReg    == 0xeb)) {
      SlaveDeviceExist = TRUE;
      SlaveDeviceType  = ATAPI_DEVICE_TYPE;
    }
  }

  //
  // When single master is plugged, slave device
  // will be wrongly detected. Here's the workaround
  // for ATA devices by detecting DRY bit in status
  // register.
  // NOTE: This workaround doesn't apply to ATAPI.
  //
  if (MasterDeviceExist && SlaveDeviceExist &&
      (StatusReg & DRDY) == 0               &&
      (InitStatusReg & DRDY) == 0           &&
      MasterDeviceType == SlaveDeviceType   &&
      SlaveDeviceType != ATAPI_DEVICE_TYPE) {
    SlaveDeviceExist = FALSE;
  }

  //
  // Indicate this channel has been detected
  //
  ChannelDeviceDetected = TRUE;
  return EFI_SUCCESS;
}

/**
  This function is used to poll for the DRQ bit clear in the Status
  Register. DRQ is cleared when the device is finished transferring data.
  So this function is called after data transfer is finished.

  @param[in] *IdeDev
  pointer pointing to IDE_BLK_IO_DEV data structure, used
  to record all the information of the IDE device.

  @param[in] TimeoutInMilliSeconds
  used to designate the timeout for the DRQ clear.

  @retval EFI_SUCCESS
  DRQ bit clear within the time out.

  @retval EFI_TIMEOUT
  DRQ bit not clear within the time out.

  @note
  Read Status Register will clear interrupt status.

**/
EFI_STATUS
DRQClear (
  IN  IDE_BLK_IO_DEV  *IdeDev,
  IN  UINTN           TimeoutInMilliSeconds
  )
// TODO: function comment is missing 'Routine Description:'
// TODO: function comment is missing 'Arguments:'
// TODO:    IdeDev - add argument and description to function comment
// TODO:    TimeoutInMilliSeconds - add argument and description to function comment
// TODO:    EFI_ABORTED - add return value to function comment
{
  UINT32  Delay;
  UINT8   StatusRegister;
  UINT8   ErrorRegister;

  Delay = (UINT32) (((TimeoutInMilliSeconds * STALL_1_MILLI_SECOND) / 30) + 1);
  do {

    StatusRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Reg.Status);

    //
    // wait for BSY == 0 and DRQ == 0
    //
    if ((StatusRegister & (DRQ | BSY)) == 0) {
      break;
    }

    if ((StatusRegister & (BSY | ERR)) == ERR) {

      ErrorRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Reg1.Error);
      if ((ErrorRegister & ABRT_ERR) == ABRT_ERR) {
        return EFI_ABORTED;
      }
    }

    //
    //  Stall for 30 us
    //
    gBS->Stall (30);

    Delay--;

  } while (Delay);

  if (Delay == 0) {
    return EFI_TIMEOUT;
  }

  return EFI_SUCCESS;
}

/**
  This function is used to poll for the DRQ bit clear in the Alternate
  Status Register. DRQ is cleared when the device is finished
  transferring data. So this function is called after data transfer
  is finished.

  @param[in] *IdeDev
  pointer pointing to IDE_BLK_IO_DEV data structure, used
  to record all the information of the IDE device.

  @param[in] TimeoutInMilliSeconds
  used to designate the timeout for the DRQ clear.

  @retval EFI_SUCCESS
  DRQ bit clear within the time out.

  @retval EFI_TIMEOUT
  DRQ bit not clear within the time out.

  @note
  Read Alternate Status Register will not clear interrupt status.

**/
EFI_STATUS
DRQClear2 (
  IN  IDE_BLK_IO_DEV  *IdeDev,
  IN  UINTN           TimeoutInMilliSeconds
  )
// TODO: function comment is missing 'Routine Description:'
// TODO: function comment is missing 'Arguments:'
// TODO:    IdeDev - add argument and description to function comment
// TODO:    TimeoutInMilliSeconds - add argument and description to function comment
// TODO:    EFI_ABORTED - add return value to function comment
{
  UINT32  Delay;
  UINT8   AltRegister;
  UINT8   ErrorRegister;

  Delay = (UINT32) (((TimeoutInMilliSeconds * STALL_1_MILLI_SECOND) / 30) + 1);
  do {

    AltRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Alt.AltStatus);

    //
    //  wait for BSY == 0 and DRQ == 0
    //
    if ((AltRegister & (DRQ | BSY)) == 0) {
      break;
    }

    if ((AltRegister & (BSY | ERR)) == ERR) {

      ErrorRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Reg1.Error);
      if ((ErrorRegister & ABRT_ERR) == ABRT_ERR) {
        return EFI_ABORTED;
      }
    }

    //
    // Stall for 30 us
    //
    gBS->Stall (30);

    Delay--;

  } while (Delay);

  if (Delay == 0) {
    return EFI_TIMEOUT;
  }

  return EFI_SUCCESS;
}

/**
  This function is used to poll for the DRQ bit set in the
  Status Register.
  DRQ is set when the device is ready to transfer data. So this function
  is called after the command is sent to the device and before required
  data is transferred.

  @param[in] IDE_BLK_IO_DEV  IN    *IdeDev
  pointer pointing to IDE_BLK_IO_DEV data structure,used
  to record all the information of the IDE device.

  @param[in] UINTN     IN    TimeoutInMilliSeconds
  used to designate the timeout for the DRQ ready.

  @retval EFI_SUCCESS
  DRQ bit set within the time out.

  @retval EFI_TIMEOUT
  DRQ bit not set within the time out.

  @retval EFI_ABORTED
  DRQ bit not set caused by the command abort.

  @note
  Read Status Register will clear interrupt status.

**/
EFI_STATUS
DRQReady (
  IN  IDE_BLK_IO_DEV  *IdeDev,
  IN  UINTN           TimeoutInMilliSeconds
  )
// TODO: function comment is missing 'Routine Description:'
// TODO: function comment is missing 'Arguments:'
// TODO:    IdeDev - add argument and description to function comment
// TODO:    TimeoutInMilliSeconds - add argument and description to function comment
{
  UINT32  Delay;
  UINT8   StatusRegister;
  UINT8   ErrorRegister;

  Delay = (UINT32) (((TimeoutInMilliSeconds * STALL_1_MILLI_SECOND) / 30) + 1);
  do {
    //
    //  read Status Register will clear interrupt
    //
    StatusRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Reg.Status);

    //
    //  BSY==0,DRQ==1
    //
    if ((StatusRegister & (BSY | DRQ)) == DRQ) {
      break;
    }

    if ((StatusRegister & (BSY | ERR)) == ERR) {

      ErrorRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Reg1.Error);
      if ((ErrorRegister & ABRT_ERR) == ABRT_ERR) {
        return EFI_ABORTED;
      }
    }

    //
    // Stall for 30 us
    //
    gBS->Stall (30);

    Delay--;
  } while (Delay);

  if (Delay == 0) {
    return EFI_TIMEOUT;
  }

  return EFI_SUCCESS;
}

/**
  This function is used to poll for the DRQ bit set in the
  Alternate Status Register. DRQ is set when the device is ready to
  transfer data. So this function is called after the command
  is sent to the device and before required data is transferred.

  @param[in] IDE_BLK_IO_DEV  IN    *IdeDev
  pointer pointing to IDE_BLK_IO_DEV data structure, used
  to record all the information of the IDE device.

  @param[in] UINTN     IN    TimeoutInMilliSeconds
  used to designate the timeout for the DRQ ready.

  @retval EFI_SUCCESS
  DRQ bit set within the time out.

  @retval EFI_TIMEOUT
  DRQ bit not set within the time out.

  @retval EFI_ABORTED
  DRQ bit not set caused by the command abort.

  @note
  Read Alternate Status Register will not clear interrupt status.

**/
EFI_STATUS
DRQReady2 (
  IN  IDE_BLK_IO_DEV  *IdeDev,
  IN  UINTN           TimeoutInMilliSeconds
  )
// TODO: function comment is missing 'Routine Description:'
// TODO: function comment is missing 'Arguments:'
// TODO:    IdeDev - add argument and description to function comment
// TODO:    TimeoutInMilliSeconds - add argument and description to function comment
{
  UINT32  Delay;
  UINT8   AltRegister;
  UINT8   ErrorRegister;

  Delay = (UINT32) (((TimeoutInMilliSeconds * STALL_1_MILLI_SECOND) / 30) + 1);

  do {
    //
    //  Read Alternate Status Register will not clear interrupt status
    //
    AltRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Alt.AltStatus);
    //
    // BSY == 0 , DRQ == 1
    //
    if ((AltRegister & (BSY | DRQ)) == DRQ) {
      break;
    }

    if ((AltRegister & (BSY | ERR)) == ERR) {

      ErrorRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Reg1.Error);
      if ((ErrorRegister & ABRT_ERR) == ABRT_ERR) {
        return EFI_ABORTED;
      }
    }

    //
    // Stall for 30 us
    //
    gBS->Stall (30);

    Delay--;
  } while (Delay);

  if (Delay == 0) {
    return EFI_TIMEOUT;
  }

  return EFI_SUCCESS;
}

/**
  This function is used to poll for the BSY bit clear in the
  Status Register. BSY is clear when the device is not busy.
  Every command must be sent after device is not busy.

  @param[in] IDE_BLK_IO_DEV  IN    *IdeDev
  pointer pointing to IDE_BLK_IO_DEV data structure, used
  to record all the information of the IDE device.

  @param[in] UINTN     IN    TimeoutInMilliSeconds
  used to designate the timeout for the DRQ ready.

  @retval EFI_SUCCESS
  BSY bit clear within the time out.

  @retval EFI_TIMEOUT
  BSY bit not clear within the time out.

  @note
  Read Status Register will clear interrupt status.

**/
EFI_STATUS
WaitForBSYClear (
  IN  IDE_BLK_IO_DEV  *IdeDev,
  IN  UINTN           TimeoutInMilliSeconds
  )
// TODO: function comment is missing 'Routine Description:'
// TODO: function comment is missing 'Arguments:'
// TODO:    IdeDev - add argument and description to function comment
// TODO:    TimeoutInMilliSeconds - add argument and description to function comment
{
  UINT32  Delay;
  UINT8   StatusRegister;

  Delay = (UINT32) (((TimeoutInMilliSeconds * STALL_1_MILLI_SECOND) / 30) + 1);
  do {

    StatusRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Reg.Status);
    if ((StatusRegister & BSY) == 0x00) {
      break;
    }

    //
    // Stall for 30 us
    //
    gBS->Stall (30);

    Delay--;

  } while (Delay);

  if (Delay == 0) {
    return EFI_TIMEOUT;
  }

  return EFI_SUCCESS;
}
//
// WaitForBSYClear2
//
/**
  This function is used to poll for the BSY bit clear in the
  Alternate Status Register. BSY is clear when the device is not busy.
  Every command must be sent after device is not busy.

  @param[in] IDE_BLK_IO_DEV  IN    *IdeDev
  pointer pointing to IDE_BLK_IO_DEV data structure, used
  to record all the information of the IDE device.

  @param[in] UINTN     IN    TimeoutInMilliSeconds
  used to designate the timeout for the DRQ ready.

  @retval EFI_SUCCESS
  BSY bit clear within the time out.

  @retval EFI_TIMEOUT
  BSY bit not clear within the time out.

  @note
  Read Alternate Status Register will not clear interrupt status.

**/
EFI_STATUS
WaitForBSYClear2 (
  IN  IDE_BLK_IO_DEV  *IdeDev,
  IN  UINTN           TimeoutInMilliSeconds
  )
// TODO: function comment is missing 'Routine Description:'
// TODO: function comment is missing 'Arguments:'
// TODO:    IdeDev - add argument and description to function comment
// TODO:    TimeoutInMilliSeconds - add argument and description to function comment
{
  UINT32  Delay;
  UINT8   AltRegister;

  Delay = (UINT32) (((TimeoutInMilliSeconds * STALL_1_MILLI_SECOND) / 30) + 1);
  do {
    AltRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Alt.AltStatus);
    if ((AltRegister & BSY) == 0x00) {
      break;
    }

    gBS->Stall (30);

    Delay--;

  } while (Delay);

  if (Delay == 0) {
    return EFI_TIMEOUT;
  }

  return EFI_SUCCESS;
}

//
// DRDYReady
//
/**
  This function is used to poll for the DRDY bit set in the
  Status Register. DRDY bit is set when the device is ready
  to accept command. Most ATA commands must be sent after
  DRDY set except the ATAPI Packet Command.

  @param[in] IDE_BLK_IO_DEV  IN    *IdeDev
  pointer pointing to IDE_BLK_IO_DEV data structure, used
  to record all the information of the IDE device.

  @param[in] UINTN     IN    TimeoutInMilliSeconds
  used to designate the timeout for the DRQ ready.

  @retval EFI_SUCCESS
  DRDY bit set within the time out.

  @retval EFI_TIMEOUT
  DRDY bit not set within the time out.

  @note
  Read Status Register will clear interrupt status.

**/
EFI_STATUS
DRDYReady (
  IN  IDE_BLK_IO_DEV  *IdeDev,
  IN  UINTN           DelayInMilliSeconds
  )
// TODO: function comment is missing 'Routine Description:'
// TODO: function comment is missing 'Arguments:'
// TODO:    IdeDev - add argument and description to function comment
// TODO:    DelayInMilliSeconds - add argument and description to function comment
// TODO:    EFI_ABORTED - add return value to function comment
{
  UINT32  Delay;
  UINT8   StatusRegister;
  UINT8   ErrorRegister;

  Delay = (UINT32) (((DelayInMilliSeconds * STALL_1_MILLI_SECOND) / 30) + 1);
  do {
    StatusRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Reg.Status);
    //
    //  BSY == 0 , DRDY == 1
    //
    if ((StatusRegister & (DRDY | BSY)) == DRDY) {
      break;
    }

    if ((StatusRegister & (BSY | ERR)) == ERR) {

      ErrorRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Reg1.Error);
      if ((ErrorRegister & ABRT_ERR) == ABRT_ERR) {
        return EFI_ABORTED;
      }
    }

    gBS->Stall (30);

    Delay--;
  } while (Delay);

  if (Delay == 0) {
    return EFI_TIMEOUT;
  }

  return EFI_SUCCESS;
}

//
// DRDYReady2
//
/**
  This function is used to poll for the DRDY bit set in the
  Alternate Status Register. DRDY bit is set when the device is ready
  to accept command. Most ATA commands must be sent after
  DRDY set except the ATAPI Packet Command.

  @param[in] IDE_BLK_IO_DEV  IN    *IdeDev
  pointer pointing to IDE_BLK_IO_DEV data structure, used
  to record all the information of the IDE device.

  @param[in] UINTN     IN    TimeoutInMilliSeconds
  used to designate the timeout for the DRQ ready.

  @retval EFI_SUCCESS
  DRDY bit set within the time out.

  @retval EFI_TIMEOUT
  DRDY bit not set within the time out.

  @note
  Read Alternate Status Register will clear interrupt status.

**/
EFI_STATUS
DRDYReady2 (
  IN  IDE_BLK_IO_DEV  *IdeDev,
  IN  UINTN           DelayInMilliSeconds
  )
// TODO: function comment is missing 'Routine Description:'
// TODO: function comment is missing 'Arguments:'
// TODO:    IdeDev - add argument and description to function comment
// TODO:    DelayInMilliSeconds - add argument and description to function comment
// TODO:    EFI_ABORTED - add return value to function comment
{
  UINT32  Delay;
  UINT8   AltRegister;
  UINT8   ErrorRegister;

  Delay = (UINT32) (((DelayInMilliSeconds * STALL_1_MILLI_SECOND) / 30) + 1);
  do {
    AltRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Alt.AltStatus);
    //
    //  BSY == 0 , DRDY == 1
    //
    if ((AltRegister & (DRDY | BSY)) == DRDY) {
      break;
    }

    if ((AltRegister & (BSY | ERR)) == ERR) {

      ErrorRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Reg1.Error);
      if ((ErrorRegister & ABRT_ERR) == ABRT_ERR) {
        return EFI_ABORTED;
      }
    }

    gBS->Stall (30);

    Delay--;
  } while (Delay);

  if (Delay == 0) {
    return EFI_TIMEOUT;
  }

  return EFI_SUCCESS;
}

//
// SwapStringChars
//
/**
  This function is a helper function used to change the char order in a
  string. It is designed specially for the PrintAtaModuleName() function.
  After the IDE device is detected, the IDE driver gets the device module
  name by sending ATA command called ATA Identify Command or ATAPI
  Identify Command to the specified IDE device. The module name returned
  is a string of ASCII characters: the first character is bit8--bit15
  of the first word, the second character is bit0--bit7 of the first word
  and so on. Thus the string can not be print directly before it is
  preprocessed by this func to change the order of characters in
  each word in the string.

  @param[in] CHAR8 IN    *Destination
  Indicates the destination string.

  @param[in] CHAR8 IN    *Source
  Indicates the source string.

  @param[in] UINT8 IN    Size
  the length of the string

**/
VOID
SwapStringChars (
  IN CHAR8  *Destination,
  IN CHAR8  *Source,
  IN UINT32 Size
  )
{
  UINT32  Index;
  CHAR8   Temp;

  for (Index = 0; Index < Size; Index += 2) {

    Temp                    = Source[Index + 1];
    Destination[Index + 1]  = Source[Index];
    Destination[Index]      = Temp;
  }
}

//
// ReleaseIdeResources
//
/**
  Release resources of an IDE device before stopping it.

  @param[in] *IdeBlkIoDevice  Standard IDE device private data structure

**/
VOID
ReleaseIdeResources (
  IN  IDE_BLK_IO_DEV  *IdeBlkIoDevice
  )
{
  if (IdeBlkIoDevice == NULL) {
    return ;
  }

  //
  // Release all the resourses occupied by the IDE_BLK_IO_DEV
  //

  if (IdeBlkIoDevice->SenseData != NULL) {
    gBS->FreePool (IdeBlkIoDevice->SenseData);
    IdeBlkIoDevice->SenseData = NULL;
  }

  if (IdeBlkIoDevice->Cache != NULL) {
    gBS->FreePool (IdeBlkIoDevice->Cache);
    IdeBlkIoDevice->Cache = NULL;
  }

  if (IdeBlkIoDevice->pIdData != NULL) {
    gBS->FreePool (IdeBlkIoDevice->pIdData);
    IdeBlkIoDevice->pIdData = NULL;
  }

  if (IdeBlkIoDevice->pInquiryData != NULL) {
    gBS->FreePool (IdeBlkIoDevice->pInquiryData);
    IdeBlkIoDevice->pInquiryData = NULL;
  }

  if (IdeBlkIoDevice->ControllerNameTable != NULL) {
    FreeUnicodeStringTable (IdeBlkIoDevice->ControllerNameTable);
    IdeBlkIoDevice->ControllerNameTable = NULL;
  }

  if (IdeBlkIoDevice->IoPort != NULL) {
    gBS->FreePool (IdeBlkIoDevice->IoPort);
  }

  if (IdeBlkIoDevice->DevicePath != NULL) {
    gBS->FreePool (IdeBlkIoDevice->DevicePath);
  }

  if (IdeBlkIoDevice->ExitBootServiceEvent != NULL) {
    gBS->CloseEvent (IdeBlkIoDevice->ExitBootServiceEvent);
    IdeBlkIoDevice->ExitBootServiceEvent = NULL;
  }

  gBS->FreePool (IdeBlkIoDevice);
  IdeBlkIoDevice = NULL;

  return ;
}

//
// SetDeviceTransferMode
//
/**
  Set the calculated Best transfer mode to a detected device

  @param[in] *IdeDev       Standard IDE device private data structure
  @param[in] *TransferMode The device transfer mode to be set

  @return Set transfer mode Command execute status

**/
EFI_STATUS
SetDeviceTransferMode (
  IN IDE_BLK_IO_DEV       *IdeDev,
  IN ATA_TRANSFER_MODE    *TransferMode
  )
// TODO: function comment is missing 'Routine Description:'
{
  EFI_STATUS  Status;
  UINT8       DeviceSelect;
  UINT8       SectorCount;

  DeviceSelect  = 0;
  DeviceSelect  = (UINT8) ((IdeDev->Device) << 4);
  SectorCount   = *((UINT8 *) TransferMode);

  //
  // Send SET FEATURE command (sub command 0x03) to set pio mode.
  //
  Status = AtaNonDataCommandIn (
            IdeDev,
            SET_FEATURES_CMD,
            DeviceSelect,
            0x03,
            SectorCount,
            0,
            0,
            0
            );

  return Status;
}

/**
  Send ATA command into device with NON_DATA protocol

  @param  IdeDev Standard IDE device private data structure
  @param  AtaCommand The ATA command to be sent
  @param  Device The value in Device register
  @param  Feature The value in Feature register
  @param  SectorCount The value in SectorCount register
  @param  LbaLow The value in LBA_LOW register
  @param  LbaMiddle The value in LBA_MIDDLE register
  @param  LbaHigh The value in LBA_HIGH register

  @retval  EFI_SUCCESS Reading succeed
  @retval  EFI_ABORTED Command failed
  @retval  EFI_DEVICE_ERROR Device status error

**/
EFI_STATUS
AtaNonDataCommandIn (
  IN  IDE_BLK_IO_DEV  *IdeDev,
  IN  UINT8           AtaCommand,
  IN  UINT8           Device,
  IN  UINT8           Feature,
  IN  UINT8           SectorCount,
  IN  UINT8           LbaLow,
  IN  UINT8           LbaMiddle,
  IN  UINT8           LbaHigh
  )
{
  EFI_STATUS  Status;
  UINT8       StatusRegister;

  Status = WaitForBSYClear (IdeDev, ATATIMEOUT);
  if (EFI_ERROR (Status)) {
    return EFI_DEVICE_ERROR;
  }

  //
  // Select device (bit4), set LBA mode(bit6) (use 0xe0 for compatibility)
  //
  IDEWritePortB (
    IdeDev->PciIo,
    IdeDev->IoPort->Head,
    (UINT8) ((IdeDev->Device << 4) | 0xe0)
    );

  //
  // ATA commands for ATA device must be issued when DRDY is set
  //
  Status = DRDYReady (IdeDev, ATATIMEOUT);
  if (EFI_ERROR (Status)) {
    return EFI_DEVICE_ERROR;
  }

  //
  // Pass parameter into device register block
  //
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->Head, Device);
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->Reg1.Feature, Feature);
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->SectorCount, SectorCount);
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->SectorNumber, LbaLow);
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->CylinderLsb, LbaMiddle);
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->CylinderMsb, LbaHigh);

  //
  // Send command via Command Register
  //
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->Reg.Command, AtaCommand);

  //
  // Wait for command completion
  // For ATA_SMART_CMD, we may need more timeout to let device
  // adjust internal states.
  //
  if (AtaCommand == ATA_SMART_CMD) {
    Status = WaitForBSYClear (IdeDev, ATASMARTTIMEOUT);
  } else {
    Status = WaitForBSYClear (IdeDev, ATATIMEOUT);
  }
  if (EFI_ERROR (Status)) {
    return EFI_DEVICE_ERROR;
  }

  StatusRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Reg.Status);
  if ((StatusRegister & ERR) == ERR) {
    //
    // Failed to execute command, abort operation
    //
    return EFI_ABORTED;
  }

  return EFI_SUCCESS;
}

/**
  Send ATA Ext command into device with NON_DATA protocol

  @param  IdeDev Standard IDE device private data structure
  @param  AtaCommand The ATA command to be sent
  @param  Device The value in Device register
  @param  Feature The value in Feature register
  @param  SectorCount The value in SectorCount register
  @param  LbaAddress The LBA address in 48-bit mode

  @retval  EFI_SUCCESS Reading succeed
  @retval  EFI_ABORTED Command failed
  @retval  EFI_DEVICE_ERROR Device status error

**/
EFI_STATUS
AtaNonDataCommandInExt (
  IN  IDE_BLK_IO_DEV  *IdeDev,
  IN  UINT8           AtaCommand,
  IN  UINT8           Device,
  IN  UINT16          Feature,
  IN  UINT16          SectorCount,
  IN  EFI_LBA         LbaAddress
  )
{
  EFI_STATUS  Status;
  UINT8       StatusRegister;
  UINT8       SectorCount8;
  UINT8       Feature8;
  UINT8       LbaLow;
  UINT8       LbaMid;
  UINT8       LbaHigh;

  Status = WaitForBSYClear (IdeDev, ATATIMEOUT);
  if (EFI_ERROR (Status)) {
    return EFI_DEVICE_ERROR;
  }

  //
  // Select device (bit4), set LBA mode(bit6) (use 0xe0 for compatibility)
  //
  IDEWritePortB (
    IdeDev->PciIo,
    IdeDev->IoPort->Head,
    (UINT8) ((IdeDev->Device << 4) | 0xe0)
    );

  //
  // ATA commands for ATA device must be issued when DRDY is set
  //
  Status = DRDYReady (IdeDev, ATATIMEOUT);
  if (EFI_ERROR (Status)) {
    return EFI_DEVICE_ERROR;
  }

  //
  // Pass parameter into device register block
  //
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->Head, Device);

  //
  // Fill the feature register, which is a two-byte FIFO. Need write twice.
  //
  Feature8 = (UINT8) (Feature >> 8);
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->Reg1.Feature, Feature8);

  Feature8 = (UINT8) Feature;
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->Reg1.Feature, Feature8);

  //
  // Fill the sector count register, which is a two-byte FIFO. Need write twice.
  //
  SectorCount8 = (UINT8) (SectorCount >> 8);
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->SectorCount, SectorCount8);

  SectorCount8 = (UINT8) SectorCount;
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->SectorCount, SectorCount8);

  //
  // Fill the start LBA registers, which are also two-byte FIFO
  //
  LbaLow  = (UINT8) RShiftU64 (LbaAddress, 24);
  LbaMid  = (UINT8) RShiftU64 (LbaAddress, 32);
  LbaHigh = (UINT8) RShiftU64 (LbaAddress, 40);
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->SectorNumber, LbaLow);
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->CylinderLsb, LbaMid);
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->CylinderMsb, LbaHigh);

  LbaLow  = (UINT8) LbaAddress;
  LbaMid  = (UINT8) RShiftU64 (LbaAddress, 8);
  LbaHigh = (UINT8) RShiftU64 (LbaAddress, 16);
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->SectorNumber, LbaLow);
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->CylinderLsb, LbaMid);
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->CylinderMsb, LbaHigh);

  //
  // Send command via Command Register
  //
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->Reg.Command, AtaCommand);

  //
  // Wait for command completion
  //
  Status = WaitForBSYClear (IdeDev, ATATIMEOUT);
  if (EFI_ERROR (Status)) {
    return EFI_DEVICE_ERROR;
  }

  StatusRegister = IDEReadPortB (IdeDev->PciIo, IdeDev->IoPort->Reg.Status);
  if ((StatusRegister & ERR) == ERR) {
    //
    // Failed to execute command, abort operation
    //
    return EFI_ABORTED;
  }

  return EFI_SUCCESS;
}

//
// SetDriveParameters
//
/**
  Set drive parameters for devices not support PACKETS command

  @param[in] IdeDev       Standard IDE device private data structure
  @param[in] DriveParameters The device parameters to be set into the disk

  @return SetParameters Command execute status

**/
EFI_STATUS
SetDriveParameters (
  IN IDE_BLK_IO_DEV       *IdeDev,
  IN ATA_DRIVE_PARMS      *DriveParameters
  )
{
  EFI_STATUS  Status;
  UINT8       DeviceSelect;

  DeviceSelect  = 0;
  DeviceSelect  = (UINT8) ((IdeDev->Device) << 4);

  //
  // Send Init drive parameters
  //
  Status = AtaNonDataCommandIn (
            IdeDev,
            INIT_DRIVE_PARAM_CMD,
            (UINT8) (DeviceSelect + DriveParameters->Heads),
            0,
            DriveParameters->Sector,
            0,
            0,
            0
            );

  //
  // Send Set Multiple parameters
  //
  Status = AtaNonDataCommandIn (
            IdeDev,
            SET_MULTIPLE_MODE_CMD,
            DeviceSelect,
            0,
            DriveParameters->MultipleSector,
            0,
            0,
            0
            );
  return Status;
}

/**
  TODO: Add function description

  @param  IdeDev TODO: add argument description

  @retval  EFI_SUCCESS TODO: Add description for return value

**/
EFI_STATUS
EnableInterrupt (
  IN IDE_BLK_IO_DEV       *IdeDev
  )
{
  UINT8 DeviceControl;

  //
  // Enable interrupt for DMA operation
  //
  DeviceControl = 0;
  IDEWritePortB (IdeDev->PciIo, IdeDev->IoPort->Alt.DeviceControl, DeviceControl);

  return EFI_SUCCESS;
}

/**
  Clear pending IDE interrupt before OS loader/kernel take control of the IDE device.

  @param[in]  Event   Pointer to this event
  @param[in]  Context Event hanlder private data

**/
VOID
EFIAPI
ClearInterrupt (
  IN EFI_EVENT  Event,
  IN VOID       *Context
  )
{
  EFI_STATUS      Status;
  UINT64          IoPortForBmis;
  UINT8           RegisterValue;
  IDE_BLK_IO_DEV  *IdeDev;

  //
  // Get our context
  //
  IdeDev = (IDE_BLK_IO_DEV *) Context;

  //
  // Obtain IDE IO port registers' base addresses
  //
  Status = ReassignIdeResources (IdeDev);
  if (EFI_ERROR (Status)) {
    return;
  }

  //
  // Check whether interrupt is pending
  //

  //
  // Reset IDE device to force it de-assert interrupt pin
  // Note: this will reset all devices on this IDE channel
  //
  AtaSoftReset (IdeDev);
  if (EFI_ERROR (Status)) {
    return;
  }

  //
  // Get base address of IDE Bus Master Status Regsiter
  //
  if (IdePrimary == IdeDev->Channel) {
    IoPortForBmis = IdeDev->IoPort->BusMasterBaseAddr + BMISP_OFFSET;
  } else {
    if (IdeSecondary == IdeDev->Channel) {
      IoPortForBmis = IdeDev->IoPort->BusMasterBaseAddr + BMISS_OFFSET;
    } else {
      return;
    }
  }
  //
  // Read BMIS register and clear ERROR and INTR bit
  //
  IdeDev->PciIo->Io.Read (
                      IdeDev->PciIo,
                      EfiPciIoWidthUint8,
                      EFI_PCI_IO_PASS_THROUGH_BAR,
                      IoPortForBmis,
                      1,
                      &RegisterValue
                      );

  RegisterValue |= (BMIS_INTERRUPT | BMIS_ERROR);

  IdeDev->PciIo->Io.Write (
                      IdeDev->PciIo,
                      EfiPciIoWidthUint8,
                      EFI_PCI_IO_PASS_THROUGH_BAR,
                      IoPortForBmis,
                      1,
                      &RegisterValue
                      );

  //
  // Select the other device on this channel to ensure this device to release the interrupt pin
  //
  if (IdeDev->Device == 0) {
    RegisterValue = (1 << 4) | 0xe0;
  } else {
    RegisterValue = (0 << 4) | 0xe0;
  }
  IDEWritePortB (
    IdeDev->PciIo,
    IdeDev->IoPort->Head,
    RegisterValue
    );

}