/*++

Copyright (c) 2006 - 2007, 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.             

Module Name:

  ScsiDisk.c

Abstract:

--*/

#include "ScsiDisk.h"

EFI_DRIVER_BINDING_PROTOCOL gScsiDiskDriverBinding = {
  ScsiDiskDriverBindingSupported,
  ScsiDiskDriverBindingStart,
  ScsiDiskDriverBindingStop,
  0xa,
  NULL,
  NULL
};

EFI_STATUS
EFIAPI
ScsiDiskDriverBindingSupported (
  IN EFI_DRIVER_BINDING_PROTOCOL  *This,
  IN EFI_HANDLE                   Controller,
  IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath
  )
/*++
  
  Routine Description:
  
  Arguments:
  
  Returns:
  
--*/
// TODO:    This - add argument and description to function comment
// TODO:    Controller - add argument and description to function comment
// TODO:    RemainingDevicePath - add argument and description to function comment
{
  EFI_STATUS            Status;
  EFI_SCSI_IO_PROTOCOL  *ScsiIo;
  UINT8                 DeviceType;

  Status = gBS->OpenProtocol (
                  Controller,
                  &gEfiScsiIoProtocolGuid,
                  (VOID **) &ScsiIo,
                  This->DriverBindingHandle,
                  Controller,
                  EFI_OPEN_PROTOCOL_BY_DRIVER
                  );
  if (EFI_ERROR (Status)) {
    return Status;
  }

  Status = ScsiIo->GetDeviceType (ScsiIo, &DeviceType);
  if (!EFI_ERROR (Status)) {
    if ((DeviceType == EFI_SCSI_TYPE_DISK) || (DeviceType == EFI_SCSI_TYPE_CDROM)) {
      Status = EFI_SUCCESS;
    } else {
      Status = EFI_UNSUPPORTED;
    }
  }

  gBS->CloseProtocol (
        Controller,
        &gEfiScsiIoProtocolGuid,
        This->DriverBindingHandle,
        Controller
        );
  return Status;
}

EFI_STATUS
EFIAPI
ScsiDiskDriverBindingStart (
  IN EFI_DRIVER_BINDING_PROTOCOL  *This,
  IN EFI_HANDLE                   Controller,
  IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath
  )
/*++
  
  Routine Description:
  
  Arguments:
  
  Returns:
  
--*/
// TODO:    This - add argument and description to function comment
// TODO:    Controller - add argument and description to function comment
// TODO:    RemainingDevicePath - add argument and description to function comment
// TODO:    EFI_DEVICE_ERROR - add return value to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  EFI_STATUS            Status;
  EFI_SCSI_IO_PROTOCOL  *ScsiIo;
  SCSI_DISK_DEV         *ScsiDiskDevice;
  BOOLEAN               Temp;
  UINT8                 Index;
  UINT8                 MaxRetry;
  BOOLEAN               NeedRetry;

  Status = gBS->AllocatePool (
                  EfiBootServicesData,
                  sizeof (SCSI_DISK_DEV),
                  (VOID **) &ScsiDiskDevice
                  );
  if (EFI_ERROR (Status)) {
    return Status;
  }

  ZeroMem (ScsiDiskDevice, sizeof (SCSI_DISK_DEV));

  Status = gBS->OpenProtocol (
                  Controller,
                  &gEfiScsiIoProtocolGuid,
                  (VOID **) &ScsiIo,
                  This->DriverBindingHandle,
                  Controller,
                  EFI_OPEN_PROTOCOL_BY_DRIVER
                  );
  if (EFI_ERROR (Status)) {
    gBS->FreePool (ScsiDiskDevice);
    return Status;
  }

  ScsiDiskDevice->Signature         = SCSI_DISK_DEV_SIGNATURE;
  ScsiDiskDevice->ScsiIo            = ScsiIo;
  ScsiDiskDevice->BlkIo.Media       = &ScsiDiskDevice->BlkIoMedia;
  ScsiDiskDevice->BlkIo.Reset       = ScsiDiskReset;
  ScsiDiskDevice->BlkIo.ReadBlocks  = ScsiDiskReadBlocks;
  ScsiDiskDevice->BlkIo.WriteBlocks = ScsiDiskWriteBlocks;
  ScsiDiskDevice->BlkIo.FlushBlocks = ScsiDiskFlushBlocks;
  ScsiDiskDevice->Handle            = Controller;

  ScsiIo->GetDeviceType (ScsiIo, &(ScsiDiskDevice->DeviceType));
  switch (ScsiDiskDevice->DeviceType) {
  case EFI_SCSI_TYPE_DISK:
    ScsiDiskDevice->BlkIo.Media->BlockSize = 0x200;
    break;

  case EFI_SCSI_TYPE_CDROM:
    ScsiDiskDevice->BlkIo.Media->BlockSize = 0x800;
    break;
  }
  //
  // The Sense Data Array's initial size is 6
  //
  ScsiDiskDevice->SenseDataNumber = 6;
  Status = gBS->AllocatePool (
                  EfiBootServicesData,
                  sizeof (EFI_SCSI_SENSE_DATA) * ScsiDiskDevice->SenseDataNumber,
                  (VOID **) &(ScsiDiskDevice->SenseData)
                  );
  if (EFI_ERROR (Status)) {
    gBS->CloseProtocol (
          Controller,
          &gEfiScsiIoProtocolGuid,
          This->DriverBindingHandle,
          Controller
          );
    gBS->FreePool (ScsiDiskDevice);
    return Status;
  }

  ZeroMem (
    ScsiDiskDevice->SenseData,
    sizeof (EFI_SCSI_SENSE_DATA) * ScsiDiskDevice->SenseDataNumber
    );

  //
  // Retrive device information
  //
  MaxRetry = 2;
  for (Index = 0; Index < MaxRetry; Index++) {
    Status = ScsiDiskInquiryDevice (ScsiDiskDevice, &NeedRetry);
    if (!EFI_ERROR (Status)) {
      break;
    }

    if (!NeedRetry) {
      gBS->FreePool (ScsiDiskDevice->SenseData);
      gBS->CloseProtocol (
            Controller,
            &gEfiScsiIoProtocolGuid,
            This->DriverBindingHandle,
            Controller
            );
      gBS->FreePool (ScsiDiskDevice);
      return EFI_DEVICE_ERROR;
    }
  }
  //
  // The second parameter "TRUE" means must
  // retrieve media capacity
  //
  Status = ScsiDiskDetectMedia (ScsiDiskDevice, TRUE, &Temp);
  if (!EFI_ERROR (Status)) {
    Status = gBS->InstallMultipleProtocolInterfaces (
                    &Controller,
                    &gEfiBlockIoProtocolGuid,
                    &ScsiDiskDevice->BlkIo,
                    NULL
                    );
  }

  if (EFI_ERROR (Status)) {
    gBS->FreePool (ScsiDiskDevice->SenseData);
    gBS->CloseProtocol (
          Controller,
          &gEfiScsiIoProtocolGuid,
          This->DriverBindingHandle,
          Controller
          );
    gBS->FreePool (ScsiDiskDevice);
    return Status;
  }

  ScsiDiskDevice->ControllerNameTable = NULL;
  AddUnicodeString (
    "eng",
    gScsiDiskComponentName.SupportedLanguages,
    &ScsiDiskDevice->ControllerNameTable,
    (CHAR16 *) L"SCSI Disk Device"
    );

  return EFI_SUCCESS;

}

EFI_STATUS
EFIAPI
ScsiDiskDriverBindingStop (
  IN  EFI_DRIVER_BINDING_PROTOCOL     *This,
  IN  EFI_HANDLE                      Controller,
  IN  UINTN                           NumberOfChildren,
  IN  EFI_HANDLE                      *ChildHandleBuffer
  )
/*++
  
  Routine Description:
  
  Arguments:
  
  Returns:
  
--*/
// TODO:    This - add argument and description to function comment
// TODO:    Controller - add argument and description to function comment
// TODO:    NumberOfChildren - add argument and description to function comment
// TODO:    ChildHandleBuffer - add argument and description to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  EFI_BLOCK_IO_PROTOCOL *BlkIo;
  SCSI_DISK_DEV         *ScsiDiskDevice;
  EFI_STATUS            Status;

  Status = gBS->OpenProtocol (
                  Controller,
                  &gEfiBlockIoProtocolGuid,
                  (VOID **) &BlkIo,
                  This->DriverBindingHandle,
                  Controller,
                  EFI_OPEN_PROTOCOL_GET_PROTOCOL
                  );
  if (EFI_ERROR (Status)) {
    return Status;
  }

  ScsiDiskDevice = SCSI_DISK_DEV_FROM_THIS (BlkIo);
  Status = gBS->UninstallProtocolInterface (
                  Controller,
                  &gEfiBlockIoProtocolGuid,
                  &ScsiDiskDevice->BlkIo
                  );
  if (!EFI_ERROR (Status)) {
    gBS->CloseProtocol (
          Controller,
          &gEfiScsiIoProtocolGuid,
          This->DriverBindingHandle,
          Controller
          );

    ReleaseScsiDiskDeviceResources (ScsiDiskDevice);

    return EFI_SUCCESS;
  }
  //
  // errors met
  //
  return Status;
}

//
// Block I/O Protocol Interface
//

EFI_STATUS
EFIAPI
ScsiDiskReset (
  IN  EFI_BLOCK_IO_PROTOCOL   *This,
  IN  BOOLEAN                 ExtendedVerification
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  This                  - TODO: add argument description
  ExtendedVerification  - TODO: add argument description

Returns:

  TODO: add return values

--*/
{
  SCSI_DISK_DEV *ScsiDiskDevice;
  EFI_STATUS    Status;
  EFI_TPL       OldTpl;

  OldTpl = gBS->RaiseTPL (TPL_CALLBACK);

  ScsiDiskDevice  = SCSI_DISK_DEV_FROM_THIS (This);

  Status          = ScsiDiskDevice->ScsiIo->ResetDevice (ScsiDiskDevice->ScsiIo);

  if (!ExtendedVerification) {
    goto Done;
  }

  Status = ScsiDiskDevice->ScsiIo->ResetBus (ScsiDiskDevice->ScsiIo);

Done:
  gBS->RestoreTPL (OldTpl);
  return Status;
}

EFI_STATUS
EFIAPI
ScsiDiskReadBlocks (
  IN  EFI_BLOCK_IO_PROTOCOL   *This,
  IN  UINT32                  MediaId,
  IN  EFI_LBA                 LBA,
  IN  UINTN                   BufferSize,
  OUT VOID                    *Buffer
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  This        - TODO: add argument description
  MediaId     - TODO: add argument description
  LBA         - TODO: add argument description
  BufferSize  - TODO: add argument description
  Buffer      - TODO: add argument description

Returns:

  EFI_INVALID_PARAMETER - TODO: Add description for return value
  EFI_SUCCESS - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_NO_MEDIA - TODO: Add description for return value
  EFI_MEDIA_CHANGED - TODO: Add description for return value
  EFI_BAD_BUFFER_SIZE - TODO: Add description for return value
  EFI_INVALID_PARAMETER - TODO: Add description for return value
  EFI_INVALID_PARAMETER - TODO: Add description for return value
  EFI_INVALID_PARAMETER - TODO: Add description for return value

--*/
{
  SCSI_DISK_DEV       *ScsiDiskDevice;
  EFI_BLOCK_IO_MEDIA  *Media;
  EFI_STATUS          Status;
  UINTN               BlockSize;
  UINTN               NumberOfBlocks;
  BOOLEAN             MediaChange;
  EFI_TPL             OldTpl;

  MediaChange = FALSE;
  if (!Buffer) {
    return EFI_INVALID_PARAMETER;
  }

  if (BufferSize == 0) {
    return EFI_SUCCESS;
  }

  OldTpl = gBS->RaiseTPL (TPL_CALLBACK);

  ScsiDiskDevice = SCSI_DISK_DEV_FROM_THIS (This);

  if (!IsDeviceFixed (ScsiDiskDevice)) {

    Status = ScsiDiskDetectMedia (ScsiDiskDevice, FALSE, &MediaChange);
    if (EFI_ERROR (Status)) {
      Status = EFI_DEVICE_ERROR;
      goto Done;
    }

    if (MediaChange) {
      gBS->ReinstallProtocolInterface (
            ScsiDiskDevice->Handle,
            &gEfiBlockIoProtocolGuid,
            &ScsiDiskDevice->BlkIo,
            &ScsiDiskDevice->BlkIo
            );
    }
  }
  //
  // Get the intrinsic block size
  //
  Media           = ScsiDiskDevice->BlkIo.Media;
  BlockSize       = Media->BlockSize;

  NumberOfBlocks  = BufferSize / BlockSize;

  if (!(Media->MediaPresent)) {
    Status = EFI_NO_MEDIA;
    goto Done;
  }

  if (MediaId != Media->MediaId) {
    Status = EFI_MEDIA_CHANGED;
    goto Done;
  }

  if (BufferSize % BlockSize != 0) {
    Status = EFI_BAD_BUFFER_SIZE;
    goto Done;
  }

  if (LBA > Media->LastBlock) {
    Status = EFI_INVALID_PARAMETER;
    goto Done;
  }

  if ((LBA + NumberOfBlocks - 1) > Media->LastBlock) {
    Status = EFI_INVALID_PARAMETER;
    goto Done;
  }

  if ((Media->IoAlign > 1) && (((UINTN) Buffer & (Media->IoAlign - 1)) != 0)) {
    Status = EFI_INVALID_PARAMETER;
    goto Done;
  }
  
  //
  // if all the parameters are valid, then perform read sectors command
  // to transfer data from device to host.
  //
  Status = ScsiDiskReadSectors (ScsiDiskDevice, Buffer, LBA, NumberOfBlocks);

Done:
  gBS->RestoreTPL (OldTpl);
  return Status;
}

EFI_STATUS
EFIAPI
ScsiDiskWriteBlocks (
  IN  EFI_BLOCK_IO_PROTOCOL   *This,
  IN  UINT32                  MediaId,
  IN  EFI_LBA                 LBA,
  IN  UINTN                   BufferSize,
  IN  VOID                    *Buffer
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  This        - TODO: add argument description
  MediaId     - TODO: add argument description
  LBA         - TODO: add argument description
  BufferSize  - TODO: add argument description
  Buffer      - TODO: add argument description

Returns:

  EFI_INVALID_PARAMETER - TODO: Add description for return value
  EFI_SUCCESS - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_NO_MEDIA - TODO: Add description for return value
  EFI_MEDIA_CHANGED - TODO: Add description for return value
  EFI_BAD_BUFFER_SIZE - TODO: Add description for return value
  EFI_INVALID_PARAMETER - TODO: Add description for return value
  EFI_INVALID_PARAMETER - TODO: Add description for return value
  EFI_INVALID_PARAMETER - TODO: Add description for return value

--*/
{
  SCSI_DISK_DEV       *ScsiDiskDevice;
  EFI_BLOCK_IO_MEDIA  *Media;
  EFI_STATUS          Status;
  UINTN               BlockSize;
  UINTN               NumberOfBlocks;
  BOOLEAN             MediaChange;
  EFI_TPL             OldTpl;

  MediaChange = FALSE;
  if (!Buffer) {
    return EFI_INVALID_PARAMETER;
  }

  if (BufferSize == 0) {
    return EFI_SUCCESS;
  }

  OldTpl = gBS->RaiseTPL (TPL_CALLBACK);

  ScsiDiskDevice = SCSI_DISK_DEV_FROM_THIS (This);

  if (!IsDeviceFixed (ScsiDiskDevice)) {

    Status = ScsiDiskDetectMedia (ScsiDiskDevice, FALSE, &MediaChange);
    if (EFI_ERROR (Status)) {
      Status = EFI_DEVICE_ERROR;
      goto Done;
    }

    if (MediaChange) {
      gBS->ReinstallProtocolInterface (
            ScsiDiskDevice->Handle,
            &gEfiBlockIoProtocolGuid,
            &ScsiDiskDevice->BlkIo,
            &ScsiDiskDevice->BlkIo
            );
    }
  }
  //
  // Get the intrinsic block size
  //
  Media           = ScsiDiskDevice->BlkIo.Media;
  BlockSize       = Media->BlockSize;

  NumberOfBlocks  = BufferSize / BlockSize;

  if (!(Media->MediaPresent)) {
    Status = EFI_NO_MEDIA;
    goto Done;
  }

  if (MediaId != Media->MediaId) {
    Status = EFI_MEDIA_CHANGED;
    goto Done;
  }

  if (BufferSize % BlockSize != 0) {
    Status = EFI_BAD_BUFFER_SIZE;
    goto Done;
  }

  if (LBA > Media->LastBlock) {
    Status = EFI_INVALID_PARAMETER;
    goto Done;
  }

  if ((LBA + NumberOfBlocks - 1) > Media->LastBlock) {
    Status = EFI_INVALID_PARAMETER;
    goto Done;
  }

  if ((Media->IoAlign > 1) && (((UINTN) Buffer & (Media->IoAlign - 1)) != 0)) {
    Status = EFI_INVALID_PARAMETER;
    goto Done;
  }
  //
  // if all the parameters are valid, then perform read sectors command
  // to transfer data from device to host.
  //
  Status = ScsiDiskWriteSectors (ScsiDiskDevice, Buffer, LBA, NumberOfBlocks);

Done:
  gBS->RestoreTPL (OldTpl);
  
  return Status;
}

EFI_STATUS
EFIAPI
ScsiDiskFlushBlocks (
  IN  EFI_BLOCK_IO_PROTOCOL   *This
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  This  - TODO: add argument description

Returns:

  EFI_SUCCESS - TODO: Add description for return value

--*/
{
  //
  // return directly
  //
  return EFI_SUCCESS;
}

EFI_STATUS
ScsiDiskDetectMedia (
  SCSI_DISK_DEV   *ScsiDiskDevice,
  BOOLEAN         MustReadCapacity,
  BOOLEAN         *MediaChange
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  ScsiDiskDevice    - TODO: add argument description
  MustReadCapacity  - TODO: add argument description
  MediaChange       - TODO: add argument description

Returns:

  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_SUCCESS - TODO: Add description for return value

--*/
{
  EFI_STATUS          Status;
  EFI_STATUS          ReadCapacityStatus;
  EFI_SCSI_SENSE_DATA *SenseData;
  UINTN               NumberOfSenseKeys;
  BOOLEAN             NeedRetry;
  BOOLEAN             NeedReadCapacity;
  UINT8               Index;
  UINT8               MaxRetry;
  EFI_BLOCK_IO_MEDIA  OldMedia;
  UINTN               Action;

  Status              = EFI_SUCCESS;
  ReadCapacityStatus  = EFI_SUCCESS;
  SenseData           = NULL;
  NumberOfSenseKeys   = 0;
  NeedReadCapacity    = FALSE;
  CopyMem (&OldMedia, ScsiDiskDevice->BlkIo.Media, sizeof (OldMedia));
  // OldMedia            = *(ScsiDiskDevice->BlkIo.Media);

  *MediaChange        = FALSE;

  MaxRetry            = 3;
  for (Index = 0; Index < MaxRetry; Index++) {
    Status = ScsiDiskTestUnitReady (
              ScsiDiskDevice,
              &NeedRetry,
              &SenseData,
              &NumberOfSenseKeys
              );
    if (!EFI_ERROR (Status)) {
      break;
    }

    if (!NeedRetry) {
      return Status;
    }
  }

  if ((Index == MaxRetry) && EFI_ERROR (Status)) {
    return EFI_DEVICE_ERROR;
  }

  Status = DetectMediaParsingSenseKeys (
            ScsiDiskDevice,
            SenseData,
            NumberOfSenseKeys,
            &Action
            );
  if (EFI_ERROR (Status)) {
    return Status;
  }
  //
  // ACTION_NO_ACTION: need not read capacity
  // other action code: need read capacity
  //
  if (Action == ACTION_NO_ACTION) {
    NeedReadCapacity = FALSE;
  } else {
    NeedReadCapacity = TRUE;
  }
  
  //
  // either NeedReadCapacity is TRUE, or MustReadCapacity is TRUE,
  // retrieve capacity via Read Capacity command
  //
  if (NeedReadCapacity || MustReadCapacity) {
    
    //
    // retrieve media information
    //
    MaxRetry = 3;
    for (Index = 0; Index < MaxRetry; Index++) {

      ReadCapacityStatus = ScsiDiskReadCapacity (
                            ScsiDiskDevice,
                            &NeedRetry,
                            &SenseData,
                            &NumberOfSenseKeys
                            );
      if (EFI_ERROR (ReadCapacityStatus) && !NeedRetry) {
        return EFI_DEVICE_ERROR;
      }
      //
      // analyze sense key to action
      //
      Status = DetectMediaParsingSenseKeys (
                ScsiDiskDevice,
                SenseData,
                NumberOfSenseKeys,
                &Action
                );
      //
      // if Status is error, it may indicate crisis error,
      // so return without retry.
      //
      if (EFI_ERROR (Status)) {
        return Status;
      }

      switch (Action) {
      case ACTION_NO_ACTION:
        //
        // no retry
        //
        Index = MaxRetry;
        break;

      case ACTION_RETRY_COMMAND_LATER:
        //
        // retry the ReadCapacity later and continuously, until the condition
        // no longer emerges.
        // stall time is 100000us, or say 0.1 second.
        //
        gBS->Stall (100000);
        Index = 0;
        break;

      default:
        //
        // other cases, just retry the command
        //
        break;
      }
    }

    if ((Index == MaxRetry) && EFI_ERROR (ReadCapacityStatus)) {
      return EFI_DEVICE_ERROR;
    }
  }

  if (ScsiDiskDevice->BlkIo.Media->MediaId != OldMedia.MediaId) {
    //
    // Media change information got from the device
    //
    *MediaChange = TRUE;
  }

  if (ScsiDiskDevice->BlkIo.Media->ReadOnly != OldMedia.ReadOnly) {
    *MediaChange = TRUE;
    ScsiDiskDevice->BlkIo.Media->MediaId += 1;
  }

  if (ScsiDiskDevice->BlkIo.Media->BlockSize != OldMedia.BlockSize) {
    *MediaChange = TRUE;
    ScsiDiskDevice->BlkIo.Media->MediaId += 1;
  }

  if (ScsiDiskDevice->BlkIo.Media->LastBlock != OldMedia.LastBlock) {
    *MediaChange = TRUE;
    ScsiDiskDevice->BlkIo.Media->MediaId += 1;
  }

  if (ScsiDiskDevice->BlkIo.Media->MediaPresent != OldMedia.MediaPresent) {
    if (ScsiDiskDevice->BlkIo.Media->MediaPresent) {
      //
      // when change from no media to media present, reset the MediaId to 1.
      //
      ScsiDiskDevice->BlkIo.Media->MediaId = 1;
    } else {
      //
      // when no media, reset the MediaId to zero.
      //
      ScsiDiskDevice->BlkIo.Media->MediaId = 0;
    }

    *MediaChange = TRUE;
  }

  return EFI_SUCCESS;
}

EFI_STATUS
ScsiDiskInquiryDevice (
  SCSI_DISK_DEV   *ScsiDiskDevice,
  BOOLEAN         *NeedRetry
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  ScsiDiskDevice  - TODO: add argument description
  NeedRetry       - TODO: add argument description

Returns:

  EFI_SUCCESS - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value

--*/
{
  UINT32              InquiryDataLength;
  UINT8               SenseDataLength;
  UINT8               HostAdapterStatus;
  UINT8               TargetStatus;
  EFI_SCSI_SENSE_DATA *SenseDataArray;
  UINTN               NumberOfSenseKeys;
  EFI_STATUS          Status;
  UINT8               MaxRetry;
  UINT8               Index;

  InquiryDataLength = sizeof (EFI_SCSI_INQUIRY_DATA);
  SenseDataLength   = 0;

  Status = SubmitInquiryCommand (
            ScsiDiskDevice->ScsiIo,
            EfiScsiStallSeconds (1),
            NULL,
            &SenseDataLength,
            &HostAdapterStatus,
            &TargetStatus,
            (VOID *) &(ScsiDiskDevice->InquiryData),
            &InquiryDataLength,
            FALSE
            );
  if ((Status == EFI_SUCCESS) || (Status == EFI_WARN_BUFFER_TOO_SMALL)) {
    //
    // no need to check HostAdapterStatus and TargetStatus
    //
    ParseInquiryData (ScsiDiskDevice);
    return EFI_SUCCESS;
  } else if (Status == EFI_NOT_READY) {
    //
    // no need to check HostAdapterStatus and TargetStatus
    //
    *NeedRetry = TRUE;
    return EFI_DEVICE_ERROR;
  } else if ((Status == EFI_INVALID_PARAMETER) || (Status == EFI_UNSUPPORTED)) {
    //
    // no need to check HostAdapterStatus and TargetStatus
    //
    *NeedRetry = FALSE;
    return EFI_DEVICE_ERROR;
  }
  //
  // go ahead to check HostAdapterStatus and TargetStatus
  // (EFI_TIMEOUT, EFI_DEVICE_ERROR)
  //
  Status = CheckHostAdapterStatus (HostAdapterStatus);
  if ((Status == EFI_TIMEOUT) || (Status == EFI_NOT_READY)) {
    *NeedRetry = TRUE;
    return EFI_DEVICE_ERROR;
  } else if (Status == EFI_DEVICE_ERROR) {
    //
    // reset the scsi channel
    //
    ScsiDiskDevice->ScsiIo->ResetBus (ScsiDiskDevice->ScsiIo);
    *NeedRetry = FALSE;
    return EFI_DEVICE_ERROR;
  }

  Status = CheckTargetStatus (TargetStatus);
  if (Status == EFI_NOT_READY) {
    //
    // reset the scsi device
    //
    ScsiDiskDevice->ScsiIo->ResetDevice (ScsiDiskDevice->ScsiIo);
    *NeedRetry = TRUE;
    return EFI_DEVICE_ERROR;
  } else if (Status == EFI_DEVICE_ERROR) {
    *NeedRetry = FALSE;
    return EFI_DEVICE_ERROR;
  }
  
  //
  // if goes here, meant SubmitInquiryCommand() failed.
  // if ScsiDiskRequestSenseKeys() succeeds at last,
  // better retry SubmitInquiryCommand(). (by setting *NeedRetry = TRUE)
  //
  MaxRetry = 3;
  for (Index = 0; Index < MaxRetry; Index++) {

    Status = ScsiDiskRequestSenseKeys (
              ScsiDiskDevice,
              NeedRetry,
              &SenseDataArray,
              &NumberOfSenseKeys,
              TRUE
              );
    if (!EFI_ERROR (Status)) {
      *NeedRetry = TRUE;
      return EFI_DEVICE_ERROR;
    }

    if (!*NeedRetry) {
      return EFI_DEVICE_ERROR;
    }
  }
  //
  // ScsiDiskRequestSenseKeys() failed after several rounds of retry.
  // set *NeedRetry = FALSE to avoid the outside caller try again.
  //
  *NeedRetry = FALSE;
  return EFI_DEVICE_ERROR;
}

EFI_STATUS
ScsiDiskTestUnitReady (
  SCSI_DISK_DEV         *ScsiDiskDevice,
  BOOLEAN               *NeedRetry,
  EFI_SCSI_SENSE_DATA   **SenseDataArray,
  UINTN                 *NumberOfSenseKeys
  )
// TODO: function comment should start with '/*++'
/*
  When Test Unit Ready command succeeds,
  retrieve Sense Keys via Request Sense;
  When Test Unit Ready command encounters any error caused by host adapter or
  target, return error without retrieving Sense Keys.
*/
// TODO: function comment should end with '--*/'
// TODO: function comment is missing 'Routine Description:'
// TODO: function comment is missing 'Arguments:'
// TODO: function comment is missing 'Returns:'
// TODO:    ScsiDiskDevice - add argument and description to function comment
// TODO:    NeedRetry - add argument and description to function comment
// TODO:    SenseDataArray - add argument and description to function comment
// TODO:    NumberOfSenseKeys - add argument and description to function comment
// TODO:    EFI_DEVICE_ERROR - add return value to function comment
// TODO:    EFI_DEVICE_ERROR - add return value to function comment
// TODO:    EFI_DEVICE_ERROR - add return value to function comment
// TODO:    EFI_DEVICE_ERROR - add return value to function comment
// TODO:    EFI_DEVICE_ERROR - add return value to function comment
// TODO:    EFI_DEVICE_ERROR - add return value to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
// TODO:    EFI_DEVICE_ERROR - add return value to function comment
// TODO:    EFI_DEVICE_ERROR - add return value to function comment
{
  EFI_STATUS  Status;
  UINT8       SenseDataLength;
  UINT8       HostAdapterStatus;
  UINT8       TargetStatus;
  UINT8       Index;
  UINT8       MaxRetry;

  SenseDataLength     = 0;
  *NumberOfSenseKeys  = 0;

  //
  // Parameter 3 and 4: do not require sense data, retrieve it when needed.
  //
  Status = SubmitTestUnitReadyCommand (
            ScsiDiskDevice->ScsiIo,
            EfiScsiStallSeconds (1),
            NULL,
            &SenseDataLength,
            &HostAdapterStatus,
            &TargetStatus
            );
  if (Status == EFI_NOT_READY) {
    //
    // no need to check HostAdapterStatus and TargetStatus
    //
    *NeedRetry = TRUE;
    return EFI_DEVICE_ERROR;
  } else if ((Status == EFI_INVALID_PARAMETER) || (Status == EFI_UNSUPPORTED)) {
    //
    // no need to check HostAdapterStatus and TargetStatus
    //
    *NeedRetry = FALSE;
    return EFI_DEVICE_ERROR;
  }
  //
  // go ahead to check HostAdapterStatus and TargetStatus
  //
  Status = CheckHostAdapterStatus (HostAdapterStatus);
  if ((Status == EFI_TIMEOUT) || (Status == EFI_NOT_READY)) {
    *NeedRetry = TRUE;
    return EFI_DEVICE_ERROR;
  } else if (Status == EFI_DEVICE_ERROR) {
    //
    // reset the scsi channel
    //
    ScsiDiskDevice->ScsiIo->ResetBus (ScsiDiskDevice->ScsiIo);
    *NeedRetry = FALSE;
    return EFI_DEVICE_ERROR;
  }

  Status = CheckTargetStatus (TargetStatus);
  if (Status == EFI_NOT_READY) {
    //
    // reset the scsi device
    //
    ScsiDiskDevice->ScsiIo->ResetDevice (ScsiDiskDevice->ScsiIo);
    *NeedRetry = TRUE;
    return EFI_DEVICE_ERROR;
  } else if (Status == EFI_DEVICE_ERROR) {
    *NeedRetry = FALSE;
    return EFI_DEVICE_ERROR;
  }

  MaxRetry = 3;
  for (Index = 0; Index < MaxRetry; Index++) {

    Status = ScsiDiskRequestSenseKeys (
              ScsiDiskDevice,
              NeedRetry,
              SenseDataArray,
              NumberOfSenseKeys,
              FALSE
              );
    if (!EFI_ERROR (Status)) {
      return EFI_SUCCESS;
    }

    if (!*NeedRetry) {
      return EFI_DEVICE_ERROR;
    }
  }
  //
  // ScsiDiskRequestSenseKeys() failed after several rounds of retry.
  // set *NeedRetry = FALSE to avoid the outside caller try again.
  //
  *NeedRetry = FALSE;
  return EFI_DEVICE_ERROR;
}

EFI_STATUS
DetectMediaParsingSenseKeys (
  SCSI_DISK_DEV           *ScsiDiskDevice,
  EFI_SCSI_SENSE_DATA     *SenseData,
  UINTN                   NumberOfSenseKeys,
  UINTN                   *Action
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  ScsiDiskDevice    - TODO: add argument description
  SenseData         - TODO: add argument description
  NumberOfSenseKeys - TODO: add argument description
  Action            - TODO: add argument description

Returns:

  EFI_SUCCESS - TODO: Add description for return value
  EFI_SUCCESS - TODO: Add description for return value
  EFI_SUCCESS - TODO: Add description for return value
  EFI_SUCCESS - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_SUCCESS - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_SUCCESS - TODO: Add description for return value

--*/
{
  BOOLEAN RetryLater;

  //
  // Default is to read capacity, unless..
  //
  *Action = ACTION_READ_CAPACITY;

  if (NumberOfSenseKeys == 0) {
    *Action = ACTION_NO_ACTION;
    return EFI_SUCCESS;
  }

  if (!ScsiDiskHaveSenseKey (SenseData, NumberOfSenseKeys)) {
    //
    // No Sense Key returned from last submitted command
    //
    *Action = ACTION_NO_ACTION;
    return EFI_SUCCESS;
  }

  if (ScsiDiskIsNoMedia (SenseData, NumberOfSenseKeys)) {
    ScsiDiskDevice->BlkIo.Media->MediaPresent = FALSE;
    ScsiDiskDevice->BlkIo.Media->LastBlock    = 0;
    *Action = ACTION_NO_ACTION;
    return EFI_SUCCESS;
  }

  if (ScsiDiskIsMediaChange (SenseData, NumberOfSenseKeys)) {
    ScsiDiskDevice->BlkIo.Media->MediaId++;
    return EFI_SUCCESS;
  }

  if (ScsiDiskIsMediaError (SenseData, NumberOfSenseKeys)) {
    ScsiDiskDevice->BlkIo.Media->MediaPresent = FALSE;
    ScsiDiskDevice->BlkIo.Media->LastBlock    = 0;
    return EFI_DEVICE_ERROR;
  }

  if (ScsiDiskIsHardwareError (SenseData, NumberOfSenseKeys)) {
    return EFI_DEVICE_ERROR;
  }

  if (!ScsiDiskIsDriveReady (SenseData, NumberOfSenseKeys, &RetryLater)) {
    if (RetryLater) {
      *Action = ACTION_RETRY_COMMAND_LATER;
      return EFI_SUCCESS;
    }

    return EFI_DEVICE_ERROR;
  }

  return EFI_SUCCESS;
}

EFI_STATUS
ScsiDiskReadCapacity (
  SCSI_DISK_DEV           *ScsiDiskDevice,
  BOOLEAN                 *NeedRetry,
  EFI_SCSI_SENSE_DATA     **SenseDataArray,
  UINTN                   *NumberOfSenseKeys
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  ScsiDiskDevice    - TODO: add argument description
  NeedRetry         - TODO: add argument description
  SenseDataArray    - TODO: add argument description
  NumberOfSenseKeys - TODO: add argument description

Returns:

  EFI_SUCCESS - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value

--*/
{
  EFI_SCSI_DISK_CAPACITY_DATA CapacityData;
  UINT32                      DataLength;
  UINT8                       HostAdapterStatus;
  UINT8                       TargetStatus;
  EFI_STATUS                  CommandStatus;
  EFI_STATUS                  Status;
  UINT8                       Index;
  UINT8                       MaxRetry;
  UINT8                       SenseDataLength;

  SenseDataLength = 0;
  ZeroMem (&CapacityData, sizeof (EFI_SCSI_DISK_CAPACITY_DATA));
  DataLength          = sizeof (EFI_SCSI_DISK_CAPACITY_DATA);

  *NumberOfSenseKeys  = 0;
  *NeedRetry          = FALSE;
  //
  // submit Read Capacity Command. in this call,not request sense data
  //
  CommandStatus = SubmitReadCapacityCommand (
                    ScsiDiskDevice->ScsiIo,
                    EfiScsiStallSeconds (1),
                    NULL,
                    &SenseDataLength,
                    &HostAdapterStatus,
                    &TargetStatus,
                    (VOID *) &CapacityData,
                    &DataLength,
                    FALSE
                    );
  if (CommandStatus == EFI_SUCCESS) {
    //
    // no need to check HostAdapterStatus and TargetStatus
    //
    GetMediaInfo (ScsiDiskDevice, &CapacityData);
    return EFI_SUCCESS;
  } else if (CommandStatus == EFI_NOT_READY) {
    //
    // no need to check HostAdapterStatus and TargetStatus
    //
    *NeedRetry = TRUE;
    return EFI_DEVICE_ERROR;
  } else if ((CommandStatus == EFI_INVALID_PARAMETER) || (CommandStatus == EFI_UNSUPPORTED)) {
    //
    // no need to check HostAdapterStatus and TargetStatus
    //
    *NeedRetry = FALSE;
    return EFI_DEVICE_ERROR;
  }
  //
  // go ahead to check HostAdapterStatus and TargetStatus
  // (EFI_TIMEOUT, EFI_DEVICE_ERROR, EFI_WARN_BUFFER_TOO_SMALL)
  //
  
  Status = CheckHostAdapterStatus (HostAdapterStatus);
  if ((Status == EFI_TIMEOUT) || (Status == EFI_NOT_READY)) {
    *NeedRetry = TRUE;
    return EFI_DEVICE_ERROR;
  } else if (Status == EFI_DEVICE_ERROR) {
    //
    // reset the scsi channel
    //
    ScsiDiskDevice->ScsiIo->ResetBus (ScsiDiskDevice->ScsiIo);
    *NeedRetry = FALSE;
    return EFI_DEVICE_ERROR;
  }

  Status = CheckTargetStatus (TargetStatus);
  if (Status == EFI_NOT_READY) {
    //
    // reset the scsi device
    //
    ScsiDiskDevice->ScsiIo->ResetDevice (ScsiDiskDevice->ScsiIo);
    *NeedRetry = TRUE;
    return EFI_DEVICE_ERROR;
  } else if (Status == EFI_DEVICE_ERROR) {
    *NeedRetry = FALSE;
    return EFI_DEVICE_ERROR;
  }
  
  //
  // if goes here, meant SubmitReadCapacityCommand() failed.
  // if ScsiDiskRequestSenseKeys() succeeds at last,
  // better retry SubmitReadCapacityCommand(). (by setting *NeedRetry = TRUE)
  //
  MaxRetry = 3;
  for (Index = 0; Index < MaxRetry; Index++) {

    Status = ScsiDiskRequestSenseKeys (
              ScsiDiskDevice,
              NeedRetry,
              SenseDataArray,
              NumberOfSenseKeys,
              TRUE
              );
    if (!EFI_ERROR (Status)) {
      *NeedRetry = TRUE;
      return EFI_DEVICE_ERROR;
    }

    if (!*NeedRetry) {
      return EFI_DEVICE_ERROR;
    }
  }
  //
  // ScsiDiskRequestSenseKeys() failed after several rounds of retry.
  // set *NeedRetry = FALSE to avoid the outside caller try again.
  //
  *NeedRetry = FALSE;
  return EFI_DEVICE_ERROR;
}

EFI_STATUS
CheckHostAdapterStatus (
  UINT8   HostAdapterStatus
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  HostAdapterStatus - TODO: add argument description

Returns:

  EFI_SUCCESS - TODO: Add description for return value
  EFI_TIMEOUT - TODO: Add description for return value
  EFI_NOT_READY - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_SUCCESS - TODO: Add description for return value

--*/
{
  switch (HostAdapterStatus) {
  case EFI_SCSI_IO_STATUS_HOST_ADAPTER_OK:
    return EFI_SUCCESS;

  case EFI_SCSI_IO_STATUS_HOST_ADAPTER_SELECTION_TIMEOUT:
  case EFI_SCSI_IO_STATUS_HOST_ADAPTER_TIMEOUT:
  case EFI_SCSI_IO_STATUS_HOST_ADAPTER_TIMEOUT_COMMAND:
    return EFI_TIMEOUT;

  case EFI_SCSI_IO_STATUS_HOST_ADAPTER_MESSAGE_REJECT:
  case EFI_SCSI_IO_STATUS_HOST_ADAPTER_PARITY_ERROR:
  case EFI_SCSI_IO_STATUS_HOST_ADAPTER_REQUEST_SENSE_FAILED:
  case EFI_SCSI_IO_STATUS_HOST_ADAPTER_DATA_OVERRUN_UNDERRUN:
  case EFI_SCSI_IO_STATUS_HOST_ADAPTER_BUS_RESET:
    return EFI_NOT_READY;

  case EFI_SCSI_IO_STATUS_HOST_ADAPTER_BUS_FREE:
  case EFI_SCSI_IO_STATUS_HOST_ADAPTER_PHASE_ERROR:
    return EFI_DEVICE_ERROR;

  default:
    return EFI_SUCCESS;
  }
}

EFI_STATUS
CheckTargetStatus (
  UINT8   TargetStatus
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  TargetStatus  - TODO: add argument description

Returns:

  EFI_SUCCESS - TODO: Add description for return value
  EFI_NOT_READY - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_SUCCESS - TODO: Add description for return value

--*/
{
  switch (TargetStatus) {
  case EFI_SCSI_IO_STATUS_TARGET_GOOD:
  case EFI_SCSI_IO_STATUS_TARGET_CHECK_CONDITION:
  case EFI_SCSI_IO_STATUS_TARGET_CONDITION_MET:
    return EFI_SUCCESS;

  case EFI_SCSI_IO_STATUS_TARGET_INTERMEDIATE:
  case EFI_SCSI_IO_STATUS_TARGET_INTERMEDIATE_CONDITION_MET:
  case EFI_SCSI_IO_STATUS_TARGET_BUSY:
  case EFI_SCSI_IO_STATUS_TARGET_COMMOND_TERMINATED:
  case EFI_SCSI_IO_STATUS_TARGET_QUEUE_FULL:
    return EFI_NOT_READY;

  case EFI_SCSI_IO_STATUS_TARGET_RESERVATION_CONFLICT:
    return EFI_DEVICE_ERROR;
    break;

  default:
    return EFI_SUCCESS;
  }
}

EFI_STATUS
ScsiDiskRequestSenseKeys (
  SCSI_DISK_DEV           *ScsiDiskDevice,
  BOOLEAN                 *NeedRetry,
  EFI_SCSI_SENSE_DATA     **SenseDataArray,
  UINTN                   *NumberOfSenseKeys,
  BOOLEAN                 AskResetIfError
  )
// TODO: function comment should start with '/*++'
/*
  Retrieve all sense keys from the device.
  When encountering error during the process,
  if retrieve sense keys before error encounterred,
  return the sense keys with return status set to EFI_SUCCESS,
  and NeedRetry set to FALSE; otherwize, return the proper return
  status.
*/
// TODO: function comment should end with '--*/'
// TODO: function comment is missing 'Routine Description:'
// TODO: function comment is missing 'Arguments:'
// TODO: function comment is missing 'Returns:'
// TODO:    ScsiDiskDevice - add argument and description to function comment
// TODO:    NeedRetry - add argument and description to function comment
// TODO:    SenseDataArray - add argument and description to function comment
// TODO:    NumberOfSenseKeys - add argument and description to function comment
// TODO:    AskResetIfError - add argument and description to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
// TODO:    EFI_DEVICE_ERROR - add return value to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  EFI_SCSI_SENSE_DATA *PtrSenseData;
  UINT8               SenseDataLength;
  BOOLEAN             SenseReq;
  EFI_STATUS          Status;
  EFI_STATUS          FallStatus;
  UINT8               HostAdapterStatus;
  UINT8               TargetStatus;

  FallStatus      = EFI_SUCCESS;
  SenseDataLength = sizeof (EFI_SCSI_SENSE_DATA);

  ZeroMem (
    ScsiDiskDevice->SenseData,
    sizeof (EFI_SCSI_SENSE_DATA) * (ScsiDiskDevice->SenseDataNumber)
    );

  *NumberOfSenseKeys  = 0;
  *SenseDataArray     = ScsiDiskDevice->SenseData;
  PtrSenseData        = ScsiDiskDevice->SenseData;

  for (SenseReq = TRUE; SenseReq;) {

    Status = SubmitRequestSenseCommand (
              ScsiDiskDevice->ScsiIo,
              EfiScsiStallSeconds (2),
              PtrSenseData,
              &SenseDataLength,
              &HostAdapterStatus,
              &TargetStatus
              );
    if ((Status == EFI_SUCCESS) || (Status == EFI_WARN_BUFFER_TOO_SMALL)) {
      FallStatus = EFI_SUCCESS;
    } else if ((Status == EFI_TIMEOUT) || (Status == EFI_NOT_READY)) { 
      *NeedRetry  = TRUE;
      FallStatus  = EFI_DEVICE_ERROR;
    } else if ((Status == EFI_INVALID_PARAMETER) || (Status == EFI_UNSUPPORTED)) {
      *NeedRetry  = FALSE;
      FallStatus  = EFI_DEVICE_ERROR;
    } else if (Status == EFI_DEVICE_ERROR) {
      if (AskResetIfError) {
        ScsiDiskDevice->ScsiIo->ResetDevice (ScsiDiskDevice->ScsiIo);
      }

      FallStatus = EFI_DEVICE_ERROR;
    }

    if (EFI_ERROR (FallStatus)) {
      if (*NumberOfSenseKeys != 0) {
        *NeedRetry = FALSE;
        return EFI_SUCCESS;
      } else {
        return EFI_DEVICE_ERROR;
      }
    }

    (*NumberOfSenseKeys) += 1;

    //
    // no more sense key or number of sense keys exceeds predefined,
    // skip the loop.
    //
    if ((PtrSenseData->Sense_Key == EFI_SCSI_SK_NO_SENSE) || 
        (*NumberOfSenseKeys == ScsiDiskDevice->SenseDataNumber)) {
      SenseReq = FALSE;
    }

    PtrSenseData += 1;

  }

  return EFI_SUCCESS;
}

VOID
GetMediaInfo (
  SCSI_DISK_DEV                 *ScsiDiskDevice,
  EFI_SCSI_DISK_CAPACITY_DATA   *Capacity
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  ScsiDiskDevice  - TODO: add argument description
  Capacity        - TODO: add argument description

Returns:

  TODO: add return values

--*/
{
  ScsiDiskDevice->BlkIo.Media->LastBlock =  (Capacity->LastLba3 << 24) |
                                            (Capacity->LastLba2 << 16) |
                                            (Capacity->LastLba1 << 8)  |
                                             Capacity->LastLba0;

  ScsiDiskDevice->BlkIo.Media->MediaPresent = TRUE;
  ScsiDiskDevice->BlkIo.Media->BlockSize = (Capacity->BlockSize3 << 24) |
                                           (Capacity->BlockSize2 << 16) | 
                                           (Capacity->BlockSize1 << 8)  |
                                            Capacity->BlockSize0;
  if (ScsiDiskDevice->DeviceType == EFI_SCSI_TYPE_DISK) {
    ScsiDiskDevice->BlkIo.Media->BlockSize = 0x200;
  }

  if (ScsiDiskDevice->DeviceType == EFI_SCSI_TYPE_CDROM) {
    ScsiDiskDevice->BlkIo.Media->BlockSize = 0x800;
  }
}

VOID
ParseInquiryData (
  SCSI_DISK_DEV   *ScsiDiskDevice
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  ScsiDiskDevice  - TODO: add argument description

Returns:

  TODO: add return values

--*/
{
  ScsiDiskDevice->FixedDevice               = (BOOLEAN) (ScsiDiskDevice->InquiryData.RMB ? 0 : 1);
  ScsiDiskDevice->BlkIoMedia.RemovableMedia = (BOOLEAN) (!ScsiDiskDevice->FixedDevice);
}

EFI_STATUS
ScsiDiskReadSectors (
  SCSI_DISK_DEV     *ScsiDiskDevice,
  VOID              *Buffer,
  EFI_LBA           Lba,
  UINTN             NumberOfBlocks
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  ScsiDiskDevice  - TODO: add argument description
  Buffer          - TODO: add argument description
  Lba             - TODO: add argument description
  NumberOfBlocks  - TODO: add argument description

Returns:

  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_SUCCESS - TODO: Add description for return value

--*/
{
  UINTN               BlocksRemaining;
  UINT32              Lba32;
  UINT8               *PtrBuffer;
  UINT32              BlockSize;
  UINT32              ByteCount;
  UINT32              MaxBlock;
  UINT32              SectorCount;
  UINT64              Timeout;
  EFI_STATUS          Status;
  UINT8               Index;
  UINT8               MaxRetry;
  BOOLEAN             NeedRetry;
  EFI_SCSI_SENSE_DATA *SenseData;
  UINTN               NumberOfSenseKeys;

  SenseData         = NULL;
  NumberOfSenseKeys = 0;

  Status            = EFI_SUCCESS;

  BlocksRemaining   = NumberOfBlocks;
  BlockSize         = ScsiDiskDevice->BlkIo.Media->BlockSize;
  //
  // limit the data bytes that can be transferred by one Read(10) Command
  //
  MaxBlock  = 65536;

  PtrBuffer = Buffer;
  Lba32     = (UINT32) Lba;

  while (BlocksRemaining > 0) {

    if (BlocksRemaining <= MaxBlock) {

      SectorCount = (UINT16) BlocksRemaining;
    } else {

      SectorCount = MaxBlock;
    }

    ByteCount = SectorCount * BlockSize;
    Timeout   = EfiScsiStallSeconds (2);

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

      Status = ScsiDiskRead10 (
                ScsiDiskDevice,
                &NeedRetry,
                &SenseData,
                &NumberOfSenseKeys,
                Timeout,
                PtrBuffer,
                &ByteCount,
                Lba32,
                SectorCount
                );
      if (!EFI_ERROR (Status)) {
        break;
      }

      if (!NeedRetry) {
        return EFI_DEVICE_ERROR;
      }

    }

    if ((Index == MaxRetry) && (Status != EFI_SUCCESS)) {
      return EFI_DEVICE_ERROR;
    }

    //
    // actual transferred sectors
    //
    SectorCount = ByteCount / BlockSize;

    Lba32 += SectorCount;
    PtrBuffer = PtrBuffer + SectorCount * BlockSize;
    BlocksRemaining -= SectorCount;
  }

  return EFI_SUCCESS;
}

EFI_STATUS
ScsiDiskWriteSectors (
  SCSI_DISK_DEV     *ScsiDiskDevice,
  VOID              *Buffer,
  EFI_LBA           Lba,
  UINTN             NumberOfBlocks
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  ScsiDiskDevice  - TODO: add argument description
  Buffer          - TODO: add argument description
  Lba             - TODO: add argument description
  NumberOfBlocks  - TODO: add argument description

Returns:

  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_DEVICE_ERROR - TODO: Add description for return value
  EFI_SUCCESS - TODO: Add description for return value

--*/
{
  UINTN               BlocksRemaining;
  UINT32              Lba32;
  UINT8               *PtrBuffer;
  UINT32              BlockSize;
  UINT32              ByteCount;
  UINT32              MaxBlock;
  UINT32              SectorCount;
  UINT64              Timeout;
  EFI_STATUS          Status;
  UINT8               Index;
  UINT8               MaxRetry;
  BOOLEAN             NeedRetry;
  EFI_SCSI_SENSE_DATA *SenseData;
  UINTN               NumberOfSenseKeys;

  SenseData         = NULL;
  NumberOfSenseKeys = 0;

  Status            = EFI_SUCCESS;

  BlocksRemaining   = NumberOfBlocks;
  BlockSize         = ScsiDiskDevice->BlkIo.Media->BlockSize;
  //
  // limit the data bytes that can be transferred by one Write(10) Command
  //
  MaxBlock  = 65536;

  PtrBuffer = Buffer;
  Lba32     = (UINT32) Lba;

  while (BlocksRemaining > 0) {

    if (BlocksRemaining <= MaxBlock) {

      SectorCount = (UINT16) BlocksRemaining;
    } else {

      SectorCount = MaxBlock;
    }

    ByteCount = SectorCount * BlockSize;
    Timeout   = EfiScsiStallSeconds (2);
    MaxRetry  = 2;
    for (Index = 0; Index < MaxRetry; Index++) {
      Status = ScsiDiskWrite10 (
                ScsiDiskDevice,
                &NeedRetry,
                &SenseData,
                &NumberOfSenseKeys,
                Timeout,
                PtrBuffer,
                &ByteCount,
                Lba32,
                SectorCount
                );
      if (!EFI_ERROR (Status)) {
        break;
      }

      if (!NeedRetry) {
        return EFI_DEVICE_ERROR;
      }
    }

    if ((Index == MaxRetry) && (Status != EFI_SUCCESS)) {
      return EFI_DEVICE_ERROR;
    }
    //
    // actual transferred sectors
    //
    SectorCount = ByteCount / BlockSize;

    Lba32 += SectorCount;
    PtrBuffer = PtrBuffer + SectorCount * BlockSize;
    BlocksRemaining -= SectorCount;
  }

  return EFI_SUCCESS;
}

EFI_STATUS
ScsiDiskRead10 (
  SCSI_DISK_DEV         *ScsiDiskDevice,
  BOOLEAN               *NeedRetry,
  EFI_SCSI_SENSE_DATA   **SenseDataArray,
  UINTN                 *NumberOfSenseKeys,
  UINT64                Timeout,
  UINT8                 *DataBuffer,
  UINT32                *DataLength,
  UINT32                StartLba,
  UINT32                SectorSize
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  ScsiDiskDevice    - TODO: add argument description
  NeedRetry         - TODO: add argument description
  SenseDataArray    - TODO: add argument description
  NumberOfSenseKeys - TODO: add argument description
  Timeout           - TODO: add argument description
  DataBuffer        - TODO: add argument description
  DataLength        - TODO: add argument description
  StartLba          - TODO: add argument description
  SectorSize        - TODO: add argument description

Returns:

  TODO: add return values

--*/
{
  UINT8       SenseDataLength;
  EFI_STATUS  Status;
  UINT8       HostAdapterStatus;
  UINT8       TargetStatus;

  *NeedRetry          = FALSE;
  *NumberOfSenseKeys  = 0;
  SenseDataLength     = 0;
  Status = SubmitRead10Command (
            ScsiDiskDevice->ScsiIo,
            Timeout,
            NULL,
            &SenseDataLength,
            &HostAdapterStatus,
            &TargetStatus,
            DataBuffer,
            DataLength,
            StartLba,
            SectorSize
            );
  return Status;
}

EFI_STATUS
ScsiDiskWrite10 (
  SCSI_DISK_DEV         *ScsiDiskDevice,
  BOOLEAN               *NeedRetry,
  EFI_SCSI_SENSE_DATA   **SenseDataArray,
  UINTN                 *NumberOfSenseKeys,
  UINT64                Timeout,
  UINT8                 *DataBuffer,
  UINT32                *DataLength,
  UINT32                StartLba,
  UINT32                SectorSize
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  ScsiDiskDevice    - TODO: add argument description
  NeedRetry         - TODO: add argument description
  SenseDataArray    - TODO: add argument description
  NumberOfSenseKeys - TODO: add argument description
  Timeout           - TODO: add argument description
  DataBuffer        - TODO: add argument description
  DataLength        - TODO: add argument description
  StartLba          - TODO: add argument description
  SectorSize        - TODO: add argument description

Returns:

  TODO: add return values

--*/
{
  EFI_STATUS  Status;
  UINT8       SenseDataLength;
  UINT8       HostAdapterStatus;
  UINT8       TargetStatus;

  *NeedRetry          = FALSE;
  *NumberOfSenseKeys  = 0;
  SenseDataLength     = 0;
  Status = SubmitWrite10Command (
            ScsiDiskDevice->ScsiIo,
            Timeout,
            NULL,
            &SenseDataLength,
            &HostAdapterStatus,
            &TargetStatus,
            DataBuffer,
            DataLength,
            StartLba,
            SectorSize
            );
  return Status;
}

BOOLEAN
ScsiDiskIsNoMedia (
  IN  EFI_SCSI_SENSE_DATA   *SenseData,
  IN  UINTN                 SenseCounts
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  SenseData   - TODO: add argument description
  SenseCounts - TODO: add argument description

Returns:

  TODO: add return values

--*/
{
  EFI_SCSI_SENSE_DATA *SensePtr;
  UINTN               Index;
  BOOLEAN             IsNoMedia;

  IsNoMedia = FALSE;
  SensePtr  = SenseData;

  for (Index = 0; Index < SenseCounts; Index++) {

    //
    // Sense Key is EFI_SCSI_SK_NOT_READY (0x2),
    // Additional Sense Code is ASC_NO_MEDIA (0x3A)
    //
    if ((SensePtr->Sense_Key == EFI_SCSI_SK_NOT_READY) &&
        (SensePtr->Addnl_Sense_Code == EFI_SCSI_ASC_NO_MEDIA)) {
      IsNoMedia = TRUE;
    }

    SensePtr++;
  }

  return IsNoMedia;
}

BOOLEAN
ScsiDiskIsMediaError (
  IN  EFI_SCSI_SENSE_DATA   *SenseData,
  IN  UINTN                 SenseCounts
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  SenseData   - TODO: add argument description
  SenseCounts - TODO: add argument description

Returns:

  TODO: add return values

--*/
{
  EFI_SCSI_SENSE_DATA *SensePtr;
  UINTN               Index;
  BOOLEAN             IsError;

  IsError   = FALSE;
  SensePtr  = SenseData;

  for (Index = 0; Index < SenseCounts; Index++) {

    switch (SensePtr->Sense_Key) {

    case EFI_SCSI_SK_MEDIUM_ERROR:
      //
      // Sense Key is EFI_SCSI_SK_MEDIUM_ERROR (0x3)
      //
      switch (SensePtr->Addnl_Sense_Code) {

      //
      // fall through
      //
      case EFI_SCSI_ASC_MEDIA_ERR1:

      //
      // fall through
      //
      case EFI_SCSI_ASC_MEDIA_ERR2:

      //
      // fall through
      //
      case EFI_SCSI_ASC_MEDIA_ERR3:
      case EFI_SCSI_ASC_MEDIA_ERR4:
        IsError = TRUE;
        break;

      default:
        break;
      }

      break;

    case EFI_SCSI_SK_NOT_READY:
      //
      // Sense Key is EFI_SCSI_SK_NOT_READY (0x2)
      //
      switch (SensePtr->Addnl_Sense_Code) {
      //
      // Additional Sense Code is ASC_MEDIA_UPSIDE_DOWN (0x6)
      //
      case EFI_SCSI_ASC_MEDIA_UPSIDE_DOWN:
        IsError = TRUE;
        break;

      default:
        break;
      }
      break;

    default:
      break;
    }

    SensePtr++;
  }

  return IsError;
}

BOOLEAN
ScsiDiskIsHardwareError (
  IN  EFI_SCSI_SENSE_DATA   *SenseData,
  IN  UINTN                 SenseCounts
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  SenseData   - TODO: add argument description
  SenseCounts - TODO: add argument description

Returns:

  TODO: add return values

--*/
{
  EFI_SCSI_SENSE_DATA *SensePtr;
  UINTN               Index;
  BOOLEAN             IsError;

  IsError   = FALSE;
  SensePtr  = SenseData;

  for (Index = 0; Index < SenseCounts; Index++) {
    
    //
    // Sense Key is EFI_SCSI_SK_HARDWARE_ERROR (0x4)
    //
    if (SensePtr->Sense_Key == EFI_SCSI_SK_HARDWARE_ERROR) {
      IsError = TRUE;
    }

    SensePtr++;
  }

  return IsError;
}

BOOLEAN
ScsiDiskIsMediaChange (
  IN  EFI_SCSI_SENSE_DATA   *SenseData,
  IN  UINTN                 SenseCounts
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  SenseData   - TODO: add argument description
  SenseCounts - TODO: add argument description

Returns:

  TODO: add return values

--*/
{
  EFI_SCSI_SENSE_DATA *SensePtr;
  UINTN               Index;
  BOOLEAN             IsMediaChanged;

  IsMediaChanged  = FALSE;
  SensePtr        = SenseData;

  for (Index = 0; Index < SenseCounts; Index++) {
    //
    // Sense Key is EFI_SCSI_SK_UNIT_ATTENTION (0x6),
    // Additional sense code is EFI_SCSI_ASC_MEDIA_CHANGE (0x28)
    //
    if ((SensePtr->Sense_Key == EFI_SCSI_SK_UNIT_ATTENTION) &&
        (SensePtr->Addnl_Sense_Code == EFI_SCSI_ASC_MEDIA_CHANGE)) {
      IsMediaChanged = TRUE;
    }

    SensePtr++;
  }

  return IsMediaChanged;
}

BOOLEAN
ScsiDiskIsResetBefore (
  IN  EFI_SCSI_SENSE_DATA   *SenseData,
  IN  UINTN                 SenseCounts
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  SenseData   - TODO: add argument description
  SenseCounts - TODO: add argument description

Returns:

  TODO: add return values

--*/
{
  EFI_SCSI_SENSE_DATA *SensePtr;
  UINTN               Index;
  BOOLEAN             IsResetBefore;

  IsResetBefore = FALSE;
  SensePtr      = SenseData;

  for (Index = 0; Index < SenseCounts; Index++) {
    
    //
    // Sense Key is EFI_SCSI_SK_UNIT_ATTENTION (0x6)
    // Additional Sense Code is EFI_SCSI_ASC_RESET (0x29)
    //
    if ((SensePtr->Sense_Key == EFI_SCSI_SK_UNIT_ATTENTION) &&
        (SensePtr->Addnl_Sense_Code == EFI_SCSI_ASC_RESET)) {
      IsResetBefore = TRUE;
    }

    SensePtr++;
  }

  return IsResetBefore;
}

BOOLEAN
ScsiDiskIsDriveReady (
  IN  EFI_SCSI_SENSE_DATA   *SenseData,
  IN  UINTN                 SenseCounts,
  OUT BOOLEAN               *RetryLater
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  SenseData   - TODO: add argument description
  SenseCounts - TODO: add argument description
  RetryLater  - TODO: add argument description

Returns:

  TODO: add return values

--*/
{
  EFI_SCSI_SENSE_DATA *SensePtr;
  UINTN               Index;
  BOOLEAN             IsReady;

  IsReady     = TRUE;
  *RetryLater = FALSE;
  SensePtr    = SenseData;

  for (Index = 0; Index < SenseCounts; Index++) {

    switch (SensePtr->Sense_Key) {

    case EFI_SCSI_SK_NOT_READY:
      //
      // Sense Key is EFI_SCSI_SK_NOT_READY (0x2)
      //
      switch (SensePtr->Addnl_Sense_Code) {
      case EFI_SCSI_ASC_NOT_READY:
        //
        // Additional Sense Code is EFI_SCSI_ASC_NOT_READY (0x4)
        //
        switch (SensePtr->Addnl_Sense_Code_Qualifier) {
        case EFI_SCSI_ASCQ_IN_PROGRESS:
          //
          // Additional Sense Code Qualifier is
          // EFI_SCSI_ASCQ_IN_PROGRESS (0x1)
          //
          IsReady     = FALSE;
          *RetryLater = TRUE;
          break;

        default:
          IsReady     = FALSE;
          *RetryLater = FALSE;
          break;
        }
        break;

      default:
        break;
      }
      break;

    default:
      break;
    }

    SensePtr++;
  }

  return IsReady;
}

BOOLEAN
ScsiDiskHaveSenseKey (
  IN  EFI_SCSI_SENSE_DATA   *SenseData,
  IN  UINTN                 SenseCounts
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  SenseData   - TODO: add argument description
  SenseCounts - TODO: add argument description

Returns:

  TODO: add return values

--*/
{
  EFI_SCSI_SENSE_DATA *SensePtr;
  UINTN               Index;
  BOOLEAN             HaveSenseKey;

  if (SenseCounts == 0) {
    HaveSenseKey = FALSE;
  } else {
    HaveSenseKey = TRUE;
  }

  SensePtr = SenseData;

  for (Index = 0; Index < SenseCounts; Index++) {
    
    //
    // Sense Key is SK_NO_SENSE (0x0)
    //
    if ((SensePtr->Sense_Key == EFI_SCSI_SK_NO_SENSE) &&
        (Index == 0)) {
      HaveSenseKey = FALSE;
    }

    SensePtr++;
  }

  return HaveSenseKey;
}

VOID
ReleaseScsiDiskDeviceResources (
  IN  SCSI_DISK_DEV   *ScsiDiskDevice
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  ScsiDiskDevice  - TODO: add argument description

Returns:

  TODO: add return values

--*/
{
  if (ScsiDiskDevice == NULL) {
    return ;
  }

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

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

  gBS->FreePool (ScsiDiskDevice);

  ScsiDiskDevice = NULL;
}