/** @file
  SCSI Bus driver that layers on every SCSI Pass Thru and
  Extended SCSI Pass Thru protocol in the system.

Copyright (c) 2006 - 2008, Intel Corporation. <BR>
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 <Uefi.h>


#include <Protocol/ScsiPassThru.h>
#include <Protocol/ScsiPassThruExt.h>
#include <Protocol/ScsiIo.h>
#include <Protocol/ComponentName.h>
#include <Protocol/DriverBinding.h>
#include <Protocol/DevicePath.h>

#include <Library/DebugLib.h>
#include <Library/UefiDriverEntryPoint.h>
#include <Library/UefiLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/ScsiLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/DevicePathLib.h>

#include "ScsiBus.h"

EFI_DRIVER_BINDING_PROTOCOL gSCSIBusDriverBinding = {
  SCSIBusDriverBindingSupported,
  SCSIBusDriverBindingStart,
  SCSIBusDriverBindingStop,
  0xa,
  NULL,
  NULL
};


//
// The ScsiBusProtocol is just used to locate ScsiBusDev
// structure in the SCSIBusDriverBindingStop(). Then we can
// Close all opened protocols and release this structure.
//
EFI_GUID  mScsiBusProtocolGuid = EFI_SCSI_BUS_PROTOCOL_GUID;

VOID  *WorkingBuffer;

EFI_STATUS
EFIAPI
ScsiioToPassThruPacket (
  IN      EFI_SCSI_IO_SCSI_REQUEST_PACKET         *Packet,
  IN OUT  EFI_SCSI_PASS_THRU_SCSI_REQUEST_PACKET  *CommandPacket
  );


EFI_STATUS
EFIAPI
PassThruToScsiioPacket (
  IN     EFI_SCSI_PASS_THRU_SCSI_REQUEST_PACKET  *ScsiPacket,
  IN OUT EFI_SCSI_IO_SCSI_REQUEST_PACKET         *Packet
  );
VOID
EFIAPI
NotifyFunction (
  EFI_EVENT  Event,
  VOID       *Context
  );

/**
  The user Entry Point for module ScsiBus. The user code starts with this function.

  @param[in] ImageHandle    The firmware allocated handle for the EFI image.
  @param[in] SystemTable    A pointer to the EFI System Table.

  @retval EFI_SUCCESS       The entry point is executed successfully.
  @retval other             Some error occurs when executing this entry point.

**/
EFI_STATUS
EFIAPI
InitializeScsiBus(
  IN EFI_HANDLE           ImageHandle,
  IN EFI_SYSTEM_TABLE     *SystemTable
  )
{
  EFI_STATUS              Status;

  //
  // Install driver model protocol(s).
  //
  Status = EfiLibInstallDriverBindingComponentName2 (
             ImageHandle,
             SystemTable,
             &gSCSIBusDriverBinding,
             ImageHandle,
             &gScsiBusComponentName,
             &gScsiBusComponentName2
             );
  ASSERT_EFI_ERROR (Status);

  return Status;
}

EFI_STATUS
EFIAPI
SCSIBusDriverBindingSupported (
  IN EFI_DRIVER_BINDING_PROTOCOL  *This,
  IN EFI_HANDLE                   Controller,
  IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath
  )
/*++

Routine Description:

  Test to see if this driver supports ControllerHandle. Any ControllerHandle
  that has ExtScsiPassThruProtocol/ScsiPassThruProtocol installed will be supported.

Arguments:

  This                - Protocol instance pointer.
  Controller          - Handle of device to test
  RemainingDevicePath - Not used

Returns:

  EFI_SUCCESS         - This driver supports this device.
  EFI_UNSUPPORTED     - This driver does not support this device.

--*/

{
  EFI_STATUS  Status;
  EFI_SCSI_PASS_THRU_PROTOCOL *PassThru;
  EFI_EXT_SCSI_PASS_THRU_PROTOCOL *ExtPassThru;
  //
  // Check for the existence of Extended SCSI Pass Thru Protocol and SCSI Pass Thru Protocol
  //
  Status = gBS->OpenProtocol (
                  Controller,
                  &gEfiExtScsiPassThruProtocolGuid,
                  (VOID **)&ExtPassThru,
                  This->DriverBindingHandle,
                  Controller,
                  EFI_OPEN_PROTOCOL_BY_DRIVER
                  );

  if (Status == EFI_ALREADY_STARTED) {
    return EFI_SUCCESS;
  }

  if (EFI_ERROR (Status)) {
    Status = gBS->OpenProtocol (
                    Controller,
                    &gEfiScsiPassThruProtocolGuid,
                    (VOID **)&PassThru,
                    This->DriverBindingHandle,
                    Controller,
                    EFI_OPEN_PROTOCOL_BY_DRIVER
                    );

    if (Status == EFI_ALREADY_STARTED) {
      return EFI_SUCCESS;
    }

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

    gBS->CloseProtocol (
      Controller,
      &gEfiScsiPassThruProtocolGuid,
      This->DriverBindingHandle,
      Controller
      );
    return EFI_SUCCESS;
  }

  gBS->CloseProtocol (
    Controller,
    &gEfiExtScsiPassThruProtocolGuid,
    This->DriverBindingHandle,
    Controller
    );

  return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
SCSIBusDriverBindingStart (
  IN EFI_DRIVER_BINDING_PROTOCOL  *This,
  IN EFI_HANDLE                   Controller,
  IN EFI_DEVICE_PATH_PROTOCOL     *RemainingDevicePath
  )
/*++

Routine Description:
  Starting the SCSI Bus Driver

Arguments:
  This                - Protocol instance pointer.
  Controller          - Handle of device to test
  RemainingDevicePath - Not used

Returns:
  EFI_SUCCESS         - This driver supports this device.
  EFI_UNSUPPORTED     - This driver does not support this device.
  EFI_DEVICE_ERROR    - This driver cannot be started due to device Error

--*/
{
  UINT64                                Lun;
  UINT8                                 *TargetId;
  BOOLEAN                               ScanOtherPuns;
  BOOLEAN                               FromFirstTarget;
  BOOLEAN                               ExtScsiSupport;
  EFI_STATUS                            Status;
  EFI_STATUS                            DevicePathStatus;
  EFI_STATUS                            PassThruStatus;
  SCSI_BUS_DEVICE                       *ScsiBusDev;
  SCSI_TARGET_ID                        *ScsiTargetId;
  EFI_DEVICE_PATH_PROTOCOL              *ParentDevicePath;
  EFI_SCSI_PASS_THRU_PROTOCOL           *ScsiInterface;
  EFI_EXT_SCSI_PASS_THRU_PROTOCOL       *ExtScsiInterface;
  EFI_SCSI_BUS_PROTOCOL                 *BusIdentify;

  TargetId        = NULL;
  ScsiTargetId    = NULL;
  ScanOtherPuns   = TRUE;
  FromFirstTarget = FALSE;
  ExtScsiSupport  = FALSE;
  PassThruStatus  = EFI_SUCCESS;
    
  ScsiTargetId = AllocateZeroPool(sizeof(SCSI_TARGET_ID));
  if (ScsiTargetId == NULL) {
    return EFI_OUT_OF_RESOURCES;
  }

  TargetId = &ScsiTargetId->ScsiId.ExtScsi[0];
  
  DevicePathStatus = gBS->OpenProtocol (
                            Controller,
                            &gEfiDevicePathProtocolGuid,
                            (VOID **) &ParentDevicePath,
                            This->DriverBindingHandle,
                            Controller,
                            EFI_OPEN_PROTOCOL_BY_DRIVER
                            );
  if (EFI_ERROR (DevicePathStatus) && (DevicePathStatus != EFI_ALREADY_STARTED)) {
    return DevicePathStatus;
  }

  //
  // To keep backward compatibility, UEFI ExtPassThru Protocol is supported as well as 
  // EFI PassThru Protocol. From priority perspective, ExtPassThru Protocol is firstly
  // tried to open on host controller handle. If fails, then PassThru Protocol is tried instead.
  //
  Status = gBS->OpenProtocol (
                  Controller,
                  &gEfiExtScsiPassThruProtocolGuid,
                  (VOID **) &ExtScsiInterface,
                  This->DriverBindingHandle,
                  Controller,
                  EFI_OPEN_PROTOCOL_BY_DRIVER
                  );
  //
  // Fail to open UEFI ExtendPassThru Protocol, then try to open EFI PassThru Protocol instead.
  //
  if (EFI_ERROR(Status) && (Status != EFI_ALREADY_STARTED)) {
    Status = gBS->OpenProtocol (
                    Controller,
                    &gEfiScsiPassThruProtocolGuid,
                    (VOID **) &ScsiInterface,
                    This->DriverBindingHandle,
                    Controller,
                    EFI_OPEN_PROTOCOL_BY_DRIVER
                    );
    //
    // Fail to open EFI PassThru Protocol, Close the DevicePathProtocol if it is opened by this time.
    //
    if (EFI_ERROR (Status) && (Status != EFI_ALREADY_STARTED)) {
      if (!EFI_ERROR(DevicePathStatus)) {
        gBS->CloseProtocol (
               Controller,
               &gEfiDevicePathProtocolGuid,
               This->DriverBindingHandle,
               Controller
               );
      } 
      return Status;
    } 
  } else {
    //
    // Succeed to open ExtPassThru Protocol, and meanwhile open PassThru Protocol 
    // with BY_DRIVER if it is also present on the handle. The intent is to prevent 
    // another SCSI Bus Driver to work on the same host handle.
    //
    ExtScsiSupport = TRUE;
    PassThruStatus = gBS->OpenProtocol (
                            Controller,
                            &gEfiScsiPassThruProtocolGuid,
                            (VOID **) &ScsiInterface,
                            This->DriverBindingHandle,
                            Controller,
                            EFI_OPEN_PROTOCOL_BY_DRIVER
                            );
  }
    
  if (Status != EFI_ALREADY_STARTED) {
    //
    // Go through here means either ExtPassThru or PassThru Protocol is successfully opened
    // on this handle for this time. Then construct Host controller private data.
    //
    ScsiBusDev = NULL;
    ScsiBusDev = AllocateZeroPool(sizeof(SCSI_BUS_DEVICE));
    if (ScsiBusDev == NULL) {
      Status = EFI_OUT_OF_RESOURCES;
      goto ErrorExit;
    }
    ScsiBusDev->Signature        = SCSI_BUS_DEVICE_SIGNATURE;
    ScsiBusDev->ExtScsiSupport   = ExtScsiSupport;
    ScsiBusDev->DevicePath       = ParentDevicePath;
    if (ScsiBusDev->ExtScsiSupport) {
      ScsiBusDev->ExtScsiInterface = ExtScsiInterface;
    } else {
      ScsiBusDev->ScsiInterface    = ScsiInterface;    
    }

    //
    // Install EFI_SCSI_BUS_PROTOCOL to the controller handle, So ScsiBusDev could be
    // retrieved on this controller handle. With ScsiBusDev, we can know which PassThru
    // Protocol is present on the handle, UEFI ExtPassThru Protocol or EFI PassThru Protocol.
    // 
    Status = gBS->InstallProtocolInterface (
                    &Controller,
                    &mScsiBusProtocolGuid,
                    EFI_NATIVE_INTERFACE,
                    &ScsiBusDev->BusIdentify
                    );
    if (EFI_ERROR (Status)) {
      goto ErrorExit;
    }
  } else {
    //
    // Go through here means Start() is re-invoked again, nothing special is required to do except
    // picking up Host controller private information.
    //
    Status = gBS->OpenProtocol (
                    Controller,
                    &mScsiBusProtocolGuid,
                    (VOID **) &BusIdentify,
                    This->DriverBindingHandle,
                    Controller,
                    EFI_OPEN_PROTOCOL_GET_PROTOCOL
                    );

    if (EFI_ERROR (Status)) {
      return Status;
    }
    ScsiBusDev = SCSI_BUS_CONTROLLER_DEVICE_FROM_THIS (BusIdentify);
  }

  if (RemainingDevicePath == NULL) {
    SetMem (ScsiTargetId, TARGET_MAX_BYTES,0xFF);
    Lun  = 0;
    FromFirstTarget = TRUE;
  } else {
    if (ScsiBusDev->ExtScsiSupport) {
      ScsiBusDev->ExtScsiInterface->GetTargetLun (ScsiBusDev->ExtScsiInterface, RemainingDevicePath, &TargetId, &Lun);  
    } else {
      ScsiBusDev->ScsiInterface->GetTargetLun (ScsiBusDev->ScsiInterface, RemainingDevicePath, &ScsiTargetId->ScsiId.Scsi, &Lun);
    }
  }

  while(ScanOtherPuns) {
    if (FromFirstTarget) {
      //
      // Remaining Device Path is NULL, scan all the possible Puns in the
      // SCSI Channel.
      //
      if (ScsiBusDev->ExtScsiSupport) {
        Status = ScsiBusDev->ExtScsiInterface->GetNextTargetLun (ScsiBusDev->ExtScsiInterface, &TargetId, &Lun);
      } else {
        Status = ScsiBusDev->ScsiInterface->GetNextDevice (ScsiBusDev->ScsiInterface, &ScsiTargetId->ScsiId.Scsi, &Lun);
      }
      if (EFI_ERROR (Status)) {
        //
        // no legal Pun and Lun found any more
        //
        break;
      }
    } else {
      ScanOtherPuns = FALSE;
    }
    //
    // Avoid creating handle for the host adapter.
    //
    if (ScsiBusDev->ExtScsiSupport) {
      if ((ScsiTargetId->ScsiId.Scsi) == ScsiBusDev->ExtScsiInterface->Mode->AdapterId) {
        continue;
      }
    } else {
      if ((ScsiTargetId->ScsiId.Scsi) == ScsiBusDev->ScsiInterface->Mode->AdapterId) {
        continue;
      }
    }
    //
    // Scan for the scsi device, if it attaches to the scsi bus,
    // then create handle and install scsi i/o protocol.
    //
    Status = ScsiScanCreateDevice (This, Controller, ScsiTargetId, Lun, ScsiBusDev);
  }
  gBS->FreePool (ScsiTargetId);
  return EFI_SUCCESS;
  
ErrorExit:
  
  if (ScsiBusDev != NULL) {
    gBS->FreePool (ScsiBusDev);
  }
  
  if (ExtScsiSupport) {
    gBS->CloseProtocol (
           Controller,
           &gEfiExtScsiPassThruProtocolGuid,
           This->DriverBindingHandle,
           Controller
           );
    if (!EFI_ERROR (PassThruStatus)) {
      gBS->CloseProtocol (
             Controller,
             &gEfiScsiPassThruProtocolGuid,
             This->DriverBindingHandle,
             Controller
             );
    }
  } else {
    gBS->CloseProtocol (
           Controller,
           &gEfiScsiPassThruProtocolGuid,
           This->DriverBindingHandle,
           Controller
           );
  }
  return Status;
}

EFI_STATUS
EFIAPI
SCSIBusDriverBindingStop (
  IN  EFI_DRIVER_BINDING_PROTOCOL     *This,
  IN  EFI_HANDLE                      Controller,
  IN  UINTN                           NumberOfChildren,
  IN  EFI_HANDLE                      *ChildHandleBuffer
  )
/*++

Routine Description:

  Stop this driver on ControllerHandle. Support stoping any child handles
  created by this driver.

Arguments:

  This              - Protocol instance pointer.
  Controller        - Handle of device to stop driver on
  NumberOfChildren  - Number of Children in the ChildHandleBuffer
  ChildHandleBuffer - List of handles for the children we need to stop.

Returns:

  EFI_SUCCESS
  Others
--*/
{
  EFI_STATUS                  Status;
  BOOLEAN                     AllChildrenStopped;
  UINTN                       Index;
  EFI_SCSI_IO_PROTOCOL        *ScsiIo;
  SCSI_IO_DEV                 *ScsiIoDevice;
  VOID                        *ScsiPassThru;
  EFI_SCSI_BUS_PROTOCOL       *Scsidentifier;
  SCSI_BUS_DEVICE             *ScsiBusDev;

  if (NumberOfChildren == 0) {
    //
    // Get the SCSI_BUS_DEVICE
    //
    Status = gBS->OpenProtocol (
                    Controller,
                    &mScsiBusProtocolGuid,
                    (VOID **) &Scsidentifier,
                    This->DriverBindingHandle,
                    Controller,
                    EFI_OPEN_PROTOCOL_GET_PROTOCOL
                    );

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

    ScsiBusDev = SCSI_BUS_CONTROLLER_DEVICE_FROM_THIS (Scsidentifier);

    //
    // Uninstall SCSI Bus Protocol
    //
    gBS->UninstallProtocolInterface (
           Controller,
           &mScsiBusProtocolGuid,
           &ScsiBusDev->BusIdentify
           );

    //
    // Close the bus driver
    //
    if (ScsiBusDev->ExtScsiSupport) {
      gBS->CloseProtocol (
             Controller,
             &gEfiExtScsiPassThruProtocolGuid,
             This->DriverBindingHandle,
             Controller
             );
    } else {
      gBS->CloseProtocol (
             Controller,
             &gEfiScsiPassThruProtocolGuid,
             This->DriverBindingHandle,
             Controller
             );
    }

    gBS->CloseProtocol (
           Controller,
           &gEfiDevicePathProtocolGuid,
           This->DriverBindingHandle,
           Controller
           );
    gBS->FreePool (ScsiBusDev);
    return EFI_SUCCESS;
  }

  AllChildrenStopped = TRUE;

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

    Status = gBS->OpenProtocol (
                    ChildHandleBuffer[Index],
                    &gEfiScsiIoProtocolGuid,
                    (VOID **) &ScsiIo,
                    This->DriverBindingHandle,
                    Controller,
                    EFI_OPEN_PROTOCOL_GET_PROTOCOL
                    );
    if (EFI_ERROR (Status)) {
      AllChildrenStopped = FALSE;
      continue;
    }

    ScsiIoDevice = SCSI_IO_DEV_FROM_THIS (ScsiIo);
    //
    // Close the child handle
    //
    if (ScsiIoDevice->ExtScsiSupport) {
      Status = gBS->CloseProtocol (
                      Controller,
                      &gEfiExtScsiPassThruProtocolGuid,
                      This->DriverBindingHandle,
                      ChildHandleBuffer[Index]
                      );

    } else {
      Status = gBS->CloseProtocol (
                      Controller,
                      &gEfiScsiPassThruProtocolGuid,
                      This->DriverBindingHandle,
                      ChildHandleBuffer[Index]
                      );
    }

    Status = gBS->UninstallMultipleProtocolInterfaces (
                    ChildHandleBuffer[Index],
                    &gEfiDevicePathProtocolGuid,
                    ScsiIoDevice->DevicePath,
                    &gEfiScsiIoProtocolGuid,
                    &ScsiIoDevice->ScsiIo,
                    NULL
                    );
    if (EFI_ERROR (Status)) {
      AllChildrenStopped = FALSE;
      if (ScsiIoDevice->ExtScsiSupport) {
        gBS->OpenProtocol (
               Controller,
               &gEfiExtScsiPassThruProtocolGuid,
               &ScsiPassThru,
               This->DriverBindingHandle,
               ChildHandleBuffer[Index],
               EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER
               );
      } else {
        gBS->OpenProtocol (
               Controller,
               &gEfiScsiPassThruProtocolGuid,
               &ScsiPassThru,
               This->DriverBindingHandle,
               ChildHandleBuffer[Index],
               EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER
               );
      }
    } else {
      gBS->FreePool (ScsiIoDevice);
    }
  }

  if (!AllChildrenStopped) {
    return EFI_DEVICE_ERROR;
  }

  return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
ScsiGetDeviceType (
  IN  EFI_SCSI_IO_PROTOCOL     *This,
  OUT UINT8                    *DeviceType
  )
/*++

Routine Description:

  Retrieves the device type information of the SCSI Controller.
    
Arguments:

  This                  - Protocol instance pointer.
  DeviceType            - A pointer to the device type information
                            retrieved from the SCSI Controller. 

Returns:

  EFI_SUCCESS           - Retrieves the device type information successfully.
  EFI_INVALID_PARAMETER - The DeviceType is NULL.
  
--*/
{
  SCSI_IO_DEV *ScsiIoDevice;

  if (DeviceType == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  ScsiIoDevice  = SCSI_IO_DEV_FROM_THIS (This);
  *DeviceType   = ScsiIoDevice->ScsiDeviceType;
  return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
ScsiGetDeviceLocation (
  IN  EFI_SCSI_IO_PROTOCOL    *This,
  IN OUT UINT8                **Target,
  OUT UINT64                  *Lun
  )
/*++

Routine Description:

  Retrieves the device location in the SCSI channel.
    
Arguments:

  This                  - Protocol instance pointer.
  Target                - A pointer to the Target Array which represents ID of a SCSI device 
                          on the SCSI channel. 
  Lun                   - A pointer to the LUN of the SCSI device on 
                          the SCSI channel.

Returns:

  EFI_SUCCESS           - Retrieves the device location successfully.
  EFI_INVALID_PARAMETER - The Target or Lun is NULL.

--*/
{
  SCSI_IO_DEV *ScsiIoDevice;

  if (Target == NULL || Lun == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  ScsiIoDevice = SCSI_IO_DEV_FROM_THIS (This);

  CopyMem (*Target,&ScsiIoDevice->Pun, TARGET_MAX_BYTES);

  *Lun         = ScsiIoDevice->Lun;

  return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
ScsiResetBus (
  IN  EFI_SCSI_IO_PROTOCOL     *This
  )
/*++

Routine Description:

  Resets the SCSI Bus that the SCSI Controller is attached to.
    
Arguments:

  This                  - Protocol instance pointer.

Returns:

  EFI_SUCCESS           - The SCSI bus is reset successfully.
  EFI_DEVICE_ERROR      - Errors encountered when resetting the SCSI bus.
  EFI_UNSUPPORTED       - The bus reset operation is not supported by the
                          SCSI Host Controller.
  EFI_TIMEOUT           - A timeout occurred while attempting to reset 
                          the SCSI bus.
--*/
{
  SCSI_IO_DEV *ScsiIoDevice;

  ScsiIoDevice = SCSI_IO_DEV_FROM_THIS (This);

  if (ScsiIoDevice->ExtScsiSupport){
    return ScsiIoDevice->ExtScsiPassThru->ResetChannel (ScsiIoDevice->ExtScsiPassThru);
  } else {
    return ScsiIoDevice->ScsiPassThru->ResetChannel (ScsiIoDevice->ScsiPassThru);
  }
}

EFI_STATUS
EFIAPI
ScsiResetDevice (
  IN  EFI_SCSI_IO_PROTOCOL     *This
  )
/*++

Routine Description:

  Resets the SCSI Controller that the device handle specifies.
    
Arguments:

  This                  - Protocol instance pointer.
    
Returns:

  EFI_SUCCESS           - Reset the SCSI controller successfully.
  EFI_DEVICE_ERROR      - Errors are encountered when resetting the
                          SCSI Controller.
  EFI_UNSUPPORTED       - The SCSI bus does not support a device 
                          reset operation.
  EFI_TIMEOUT           - A timeout occurred while attempting to 
                          reset the SCSI Controller.
--*/
{
  SCSI_IO_DEV  *ScsiIoDevice;
  UINT8        Target[TARGET_MAX_BYTES];

  ScsiIoDevice = SCSI_IO_DEV_FROM_THIS (This);
  CopyMem (Target,&ScsiIoDevice->Pun, TARGET_MAX_BYTES);


  if (ScsiIoDevice->ExtScsiSupport) {
    return ScsiIoDevice->ExtScsiPassThru->ResetTargetLun (
                                        ScsiIoDevice->ExtScsiPassThru,
                                        Target,
                                        ScsiIoDevice->Lun
                                          );
  } else {
    return ScsiIoDevice->ScsiPassThru->ResetTarget (
                                          ScsiIoDevice->ScsiPassThru,
                                          ScsiIoDevice->Pun.ScsiId.Scsi,
                                          ScsiIoDevice->Lun
                                            );
  }
}

EFI_STATUS
EFIAPI
ScsiExecuteSCSICommand (
  IN  EFI_SCSI_IO_PROTOCOL                         *This,
  IN OUT  EFI_SCSI_IO_SCSI_REQUEST_PACKET          *Packet,
  IN EFI_EVENT                                     Event  OPTIONAL
  )
/*++

Routine Description:

  Sends a SCSI Request Packet to the SCSI Controller for execution.
    
Arguments:

  This                  - Protocol instance pointer.
  Packet                - The SCSI request packet to send to the SCSI 
                          Controller specified by the device handle.
  Event                 - If the SCSI bus where the SCSI device is attached
                          does not support non-blocking I/O, then Event is 
                          ignored, and blocking I/O is performed.  
                          If Event is NULL, then blocking I/O is performed.
                          If Event is not NULL and non-blocking I/O is 
                          supported, then non-blocking I/O is performed,
                          and Event will be signaled when the SCSI Request
                          Packet completes.
Returns:

  EFI_SUCCESS           - The SCSI Request Packet was sent by the host 
                          successfully, and TransferLength bytes were 
                          transferred to/from DataBuffer.See 
                          HostAdapterStatus, TargetStatus, 
                          SenseDataLength, and SenseData in that order
                          for additional status information.
  EFI_BAD_BUFFER_SIZE  - The SCSI Request Packet was executed, 
                          but the entire DataBuffer could not be transferred.
                          The actual number of bytes transferred is returned
                          in TransferLength. See HostAdapterStatus, 
                          TargetStatus, SenseDataLength, and SenseData in 
                          that order for additional status information.
  EFI_NOT_READY         - The SCSI Request Packet could not be sent because 
                          there are too many SCSI Command Packets already 
                          queued.The caller may retry again later.
  EFI_DEVICE_ERROR      - A device error occurred while attempting to send 
                          the SCSI Request Packet. See HostAdapterStatus, 
                          TargetStatus, SenseDataLength, and SenseData in 
                          that order for additional status information.
  EFI_INVALID_PARAMETER - The contents of CommandPacket are invalid.  
                          The SCSI Request Packet was not sent, so no 
                          additional status information is available.
  EFI_UNSUPPORTED       - The command described by the SCSI Request Packet
                          is not supported by the SCSI initiator(i.e., SCSI 
                          Host Controller). The SCSI Request Packet was not
                          sent, so no additional status information is 
                          available.
  EFI_TIMEOUT           - A timeout occurred while waiting for the SCSI 
                          Request Packet to execute. See HostAdapterStatus,
                          TargetStatus, SenseDataLength, and SenseData in 
                          that order for additional status information.
--*/
{
  SCSI_IO_DEV                                 *ScsiIoDevice;
  EFI_STATUS                                  Status;
  UINT8                                       Target[TARGET_MAX_BYTES];
  EFI_EVENT                                   PacketEvent;
  EFI_EXT_SCSI_PASS_THRU_SCSI_REQUEST_PACKET  *ExtRequestPacket;
  SCSI_EVENT_DATA                             EventData;                                     

  PacketEvent = NULL;
  
  if (Packet == NULL) {
    return EFI_INVALID_PARAMETER;
  }

  ScsiIoDevice  = SCSI_IO_DEV_FROM_THIS (This);
  CopyMem (Target,&ScsiIoDevice->Pun, TARGET_MAX_BYTES);

  if (ScsiIoDevice->ExtScsiSupport) {
    ExtRequestPacket = (EFI_EXT_SCSI_PASS_THRU_SCSI_REQUEST_PACKET *) Packet;
    Status = ScsiIoDevice->ExtScsiPassThru->PassThru (
                                          ScsiIoDevice->ExtScsiPassThru,
                                          Target,
                                          ScsiIoDevice->Lun,
                                          ExtRequestPacket,
                                          Event
                                          );
  } else {

    Status = gBS->AllocatePool (
                     EfiBootServicesData,
                     sizeof(EFI_SCSI_PASS_THRU_SCSI_REQUEST_PACKET),
                     (VOID**)&WorkingBuffer
                     );

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

    //
    // Convert package into EFI1.0, EFI_SCSI_PASS_THRU_SCSI_REQUEST_PACKET.
    //
    Status = ScsiioToPassThruPacket(Packet, (EFI_SCSI_PASS_THRU_SCSI_REQUEST_PACKET*)WorkingBuffer);
    if (EFI_ERROR(Status)) {
      gBS->FreePool(WorkingBuffer);
      return Status;
    }

    if ((ScsiIoDevice->ScsiPassThru->Mode->Attributes & EFI_SCSI_PASS_THRU_ATTRIBUTES_NONBLOCKIO) && (Event !=  NULL)) {
      EventData.Data1 = (VOID*)Packet;
      EventData.Data2 = Event;
      //
      // Create Event
      //
      Status = gBS->CreateEvent (
                       EVT_NOTIFY_SIGNAL,
                       TPL_CALLBACK,
                       NotifyFunction,
                       &EventData,
                       &PacketEvent
                       );
      if (EFI_ERROR(Status)) {
        gBS->FreePool(WorkingBuffer);
        return Status;
      }

      Status = ScsiIoDevice->ScsiPassThru->PassThru (
                                          ScsiIoDevice->ScsiPassThru,
                                          ScsiIoDevice->Pun.ScsiId.Scsi,
                                          ScsiIoDevice->Lun,
                                          WorkingBuffer,
                                          PacketEvent
                                          );

      if (EFI_ERROR(Status)) {
        gBS->FreePool(WorkingBuffer);
        gBS->CloseEvent(PacketEvent);
        return Status;
      }

    } else {
      //
      // If there's no event or SCSI Device doesn't support NON-BLOCKING, just convert
      // EFI1.0 PassThru packet back to UEFI2.0 SCSI IO Packet.
      //
      Status = ScsiIoDevice->ScsiPassThru->PassThru (
                                          ScsiIoDevice->ScsiPassThru,
                                          ScsiIoDevice->Pun.ScsiId.Scsi,
                                          ScsiIoDevice->Lun,
                                          WorkingBuffer,
                                          Event
                                          );
      if (EFI_ERROR(Status)) {
        gBS->FreePool(WorkingBuffer);
        return Status;
      }

      PassThruToScsiioPacket((EFI_SCSI_PASS_THRU_SCSI_REQUEST_PACKET*)WorkingBuffer,Packet);
      //
      // After converting EFI1.0 PassThru Packet back to UEFI2.0 SCSI IO Packet,
      // free WorkingBuffer.
      //
      gBS->FreePool(WorkingBuffer);
    }
  }
  return Status;
}

EFI_STATUS
EFIAPI
ScsiScanCreateDevice (
  EFI_DRIVER_BINDING_PROTOCOL   *This,
  EFI_HANDLE                    Controller,
  SCSI_TARGET_ID                *TargetId,
  UINT64                        Lun,
  SCSI_BUS_DEVICE               *ScsiBusDev
  )
/*++

Routine Description:

  Scan SCSI Bus to discover the device, and attach ScsiIoProtocol to it.

Arguments:

  This              - Protocol instance pointer
  Controller        - Controller handle
  Pun               - The Pun of the SCSI device on the SCSI channel.
  Lun               - The Lun of the SCSI device on the SCSI channel.
  ScsiBusDev        - The pointer of SCSI_BUS_DEVICE

Returns:

  EFI_SUCCESS       - Successfully to discover the device and attach ScsiIoProtocol to it.
  EFI_OUT_OF_RESOURCES - Fail to discover the device.

--*/
{
  EFI_STATUS                Status;
  SCSI_IO_DEV               *ScsiIoDevice;
  EFI_DEVICE_PATH_PROTOCOL  *ScsiDevicePath;

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

  ZeroMem (ScsiIoDevice, sizeof (SCSI_IO_DEV));

  ScsiIoDevice->Signature                 = SCSI_IO_DEV_SIGNATURE;
  CopyMem(&ScsiIoDevice->Pun, TargetId, TARGET_MAX_BYTES);
  ScsiIoDevice->Lun                       = Lun;

  if (ScsiBusDev->ExtScsiSupport) {
    ScsiIoDevice->ExtScsiPassThru         = ScsiBusDev->ExtScsiInterface;
    ScsiIoDevice->ExtScsiSupport          = TRUE;
    ScsiIoDevice->ScsiIo.IoAlign          = ScsiIoDevice->ExtScsiPassThru->Mode->IoAlign;

  } else {
    ScsiIoDevice->ScsiPassThru            = ScsiBusDev->ScsiInterface;
    ScsiIoDevice->ExtScsiSupport          = FALSE;
    ScsiIoDevice->ScsiIo.IoAlign          = ScsiIoDevice->ScsiPassThru->Mode->IoAlign;
  }

  ScsiIoDevice->ScsiIo.GetDeviceType      = ScsiGetDeviceType;
  ScsiIoDevice->ScsiIo.GetDeviceLocation  = ScsiGetDeviceLocation;
  ScsiIoDevice->ScsiIo.ResetBus           = ScsiResetBus;
  ScsiIoDevice->ScsiIo.ResetDevice        = ScsiResetDevice;
  ScsiIoDevice->ScsiIo.ExecuteScsiCommand = ScsiExecuteSCSICommand;


  if (!DiscoverScsiDevice (ScsiIoDevice)) {
    gBS->FreePool (ScsiIoDevice);
    return EFI_OUT_OF_RESOURCES;
  }

  //
  // Set Device Path
  //
  if (ScsiIoDevice->ExtScsiSupport){
    Status = ScsiIoDevice->ExtScsiPassThru->BuildDevicePath (
                                          ScsiIoDevice->ExtScsiPassThru,
                                          &ScsiIoDevice->Pun.ScsiId.ExtScsi[0],
                                          ScsiIoDevice->Lun,
                                          &ScsiDevicePath
                                          );
    if (Status == EFI_OUT_OF_RESOURCES) {
      gBS->FreePool (ScsiIoDevice);
      return Status;
    }
  } else {
    Status = ScsiIoDevice->ScsiPassThru->BuildDevicePath (
                                          ScsiIoDevice->ScsiPassThru,
                                          ScsiIoDevice->Pun.ScsiId.Scsi,
                                          ScsiIoDevice->Lun,
                                          &ScsiDevicePath
                                          );
    if (Status == EFI_OUT_OF_RESOURCES) {
      gBS->FreePool (ScsiIoDevice);
      return Status;
    }
  }

  ScsiIoDevice->DevicePath = AppendDevicePathNode (
                              ScsiBusDev->DevicePath,
                              ScsiDevicePath
                              );
  //
  // The memory space for ScsiDevicePath is allocated in
  // ScsiPassThru->BuildDevicePath() function; It is no longer used
  // after EfiAppendDevicePathNode,so free the memory it occupies.
  //
  gBS->FreePool (ScsiDevicePath);

  if (ScsiIoDevice->DevicePath == NULL) {
    gBS->FreePool (ScsiIoDevice);
    return EFI_OUT_OF_RESOURCES;
  }

  Status = gBS->InstallMultipleProtocolInterfaces (
                  &ScsiIoDevice->Handle,
                  &gEfiDevicePathProtocolGuid,
                  ScsiIoDevice->DevicePath,
                  &gEfiScsiIoProtocolGuid,
                  &ScsiIoDevice->ScsiIo,
                  NULL
                  );
  if (EFI_ERROR (Status)) {
    gBS->FreePool (ScsiIoDevice);
    return EFI_OUT_OF_RESOURCES;
  } else {
    if (ScsiBusDev->ExtScsiSupport) {
      gBS->OpenProtocol (
            Controller,
            &gEfiExtScsiPassThruProtocolGuid,
            (VOID **) &(ScsiBusDev->ExtScsiInterface),
            This->DriverBindingHandle,
            ScsiIoDevice->Handle,
            EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER
            );
     } else {
      gBS->OpenProtocol (
            Controller,
            &gEfiScsiPassThruProtocolGuid,
            (VOID **) &(ScsiBusDev->ScsiInterface),
            This->DriverBindingHandle,
            ScsiIoDevice->Handle,
            EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER
            );
     }
  }
  return EFI_SUCCESS;
}

BOOLEAN
EFIAPI
DiscoverScsiDevice (
  SCSI_IO_DEV   *ScsiIoDevice
  )
/*++

Routine Description:

  Discovery SCSI Device

Arguments:

  ScsiIoDevice    - The pointer of SCSI_IO_DEV

Returns:

  TRUE            - Find SCSI Device and verify it.
  FALSE           - Unable to find SCSI Device.

--*/
{
  EFI_STATUS            Status;
  UINT32                InquiryDataLength;
  UINT8                 SenseDataLength;
  UINT8                 HostAdapterStatus;
  UINT8                 TargetStatus;
  EFI_SCSI_SENSE_DATA   SenseData;
  EFI_SCSI_INQUIRY_DATA InquiryData;

  HostAdapterStatus = 0;
  TargetStatus      = 0;
  //
  // Using Inquiry command to scan for the device
  //
  InquiryDataLength = sizeof (EFI_SCSI_INQUIRY_DATA);
  SenseDataLength   = sizeof (EFI_SCSI_SENSE_DATA);

  Status = ScsiInquiryCommand (
            &ScsiIoDevice->ScsiIo,
            EFI_SCSI_STALL_SECONDS (1),
            (VOID *) &SenseData,
            &SenseDataLength,
            &HostAdapterStatus,
            &TargetStatus,
            (VOID *) &InquiryData,
            &InquiryDataLength,
            FALSE
            );
  if (EFI_ERROR (Status)) {
    //
    //    ParseSenseData (&SenseData,SenseDataLength);
    //
    return FALSE;
  }
  //
  // Retrieved inquiry data successfully
  //
  if ((InquiryData.Peripheral_Qualifier != 0) &&
      (InquiryData.Peripheral_Qualifier != 3)) {
    return FALSE;
  }

  if (InquiryData.Peripheral_Qualifier == 3) {
    if (InquiryData.Peripheral_Type != 0x1f) {
      return FALSE;
    }
  }

  if (0x1e >= InquiryData.Peripheral_Type && InquiryData.Peripheral_Type >= 0xa) {
    return FALSE;
  }

  //
  // valid device type and peripheral qualifier combination.
  //
  ScsiIoDevice->ScsiDeviceType  = InquiryData.Peripheral_Type;
  ScsiIoDevice->RemovableDevice = InquiryData.RMB;
  if (InquiryData.Version == 0) {
    ScsiIoDevice->ScsiVersion = 0;
  } else {
    //
    // ANSI-approved version
    //
    ScsiIoDevice->ScsiVersion = (UINT8) (InquiryData.Version & 0x03);
  }

  return TRUE;
}


EFI_STATUS
EFIAPI
ScsiioToPassThruPacket (
  IN      EFI_SCSI_IO_SCSI_REQUEST_PACKET         *Packet,
  IN OUT  EFI_SCSI_PASS_THRU_SCSI_REQUEST_PACKET  *CommandPacket
  )
/*++

Routine Description:

  Convert EFI_SCSI_IO_SCSI_REQUEST_PACKET packet to
  EFI_SCSI_PASS_THRU_SCSI_REQUEST_PACKET packet

Arguments:

  Packet            - The pointer of EFI_SCSI_IO_SCSI_REQUEST_PACKET
  CommandPacket     - The pointer of EFI_SCSI_PASS_THRU_SCSI_REQUEST_PACKET

Returns:

  NONE

--*/
{
  //
  //EFI 1.10 doesn't support Bi-Direction Command.
  //
  if (Packet->DataDirection == EFI_SCSI_IO_DATA_DIRECTION_BIDIRECTIONAL) {
    return EFI_UNSUPPORTED;
  }

  ZeroMem (CommandPacket, sizeof (EFI_SCSI_PASS_THRU_SCSI_REQUEST_PACKET));

  CommandPacket->Timeout           = Packet->Timeout;
  CommandPacket->Cdb               = Packet->Cdb;
  CommandPacket->CdbLength         = Packet->CdbLength;
  CommandPacket->DataDirection     = Packet->DataDirection;
  CommandPacket->HostAdapterStatus = Packet->HostAdapterStatus;
  CommandPacket->TargetStatus      = Packet->TargetStatus;
  CommandPacket->SenseData         = Packet->SenseData;
  CommandPacket->SenseDataLength   = Packet->SenseDataLength;

  if (Packet->DataDirection == EFI_SCSI_IO_DATA_DIRECTION_READ) {
    CommandPacket->DataBuffer = Packet->InDataBuffer;
    CommandPacket->TransferLength = Packet->InTransferLength;
  } else if (Packet->DataDirection == EFI_SCSI_IO_DATA_DIRECTION_WRITE) {
    CommandPacket->DataBuffer = Packet->OutDataBuffer;
    CommandPacket->TransferLength = Packet->OutTransferLength;
  }
  return EFI_SUCCESS;
}


EFI_STATUS
EFIAPI
PassThruToScsiioPacket (
  IN     EFI_SCSI_PASS_THRU_SCSI_REQUEST_PACKET  *ScsiPacket,
  IN OUT EFI_SCSI_IO_SCSI_REQUEST_PACKET         *Packet
  )
/*++

Routine Description:

  Convert EFI_SCSI_PASS_THRU_SCSI_REQUEST_PACKET packet to
  EFI_SCSI_IO_SCSI_REQUEST_PACKET packet

Arguments:

  ScsiPacket        - The pointer of EFI_SCSI_PASS_THRU_SCSI_REQUEST_PACKET
  Packet            - The pointer of EFI_SCSI_IO_SCSI_REQUEST_PACKET

Returns:

  NONE

--*/
{
  Packet->Timeout           = ScsiPacket->Timeout;
  Packet->Cdb               = ScsiPacket->Cdb;
  Packet->CdbLength         = ScsiPacket->CdbLength;
  Packet->DataDirection     = ScsiPacket->DataDirection;
  Packet->HostAdapterStatus = ScsiPacket->HostAdapterStatus;
  Packet->TargetStatus      = ScsiPacket->TargetStatus;
  Packet->SenseData         = ScsiPacket->SenseData;
  Packet->SenseDataLength   = ScsiPacket->SenseDataLength;

  if (ScsiPacket->DataDirection == EFI_SCSI_IO_DATA_DIRECTION_READ) {
    Packet->InDataBuffer = ScsiPacket->DataBuffer;
    Packet->InTransferLength = ScsiPacket->TransferLength;
  } else if (Packet->DataDirection == EFI_SCSI_IO_DATA_DIRECTION_WRITE) {
    Packet->OutDataBuffer = ScsiPacket->DataBuffer;
    Packet->OutTransferLength = ScsiPacket->TransferLength;
  }

  return EFI_SUCCESS;
}



VOID
EFIAPI
NotifyFunction (
  EFI_EVENT  Event,
  VOID       *Context
  )
/*++

Routine Description:

  Notify Function in which convert EFI1.0 PassThru Packet back to UEF2.0
  SCSI IO Packet.

Arguments:

  Event          - The instance of EFI_EVENT.
  Context        - The parameter passed in.

Returns:

  NONE

--*/
{
  EFI_SCSI_IO_SCSI_REQUEST_PACKET          *Packet;
  EFI_SCSI_PASS_THRU_SCSI_REQUEST_PACKET   *ScsiPacket;
  EFI_EVENT                                CallerEvent;
  SCSI_EVENT_DATA                          *PassData;

  PassData = (SCSI_EVENT_DATA*)Context;
  Packet  = (EFI_SCSI_IO_SCSI_REQUEST_PACKET *)PassData->Data1;
  ScsiPacket =  (EFI_SCSI_PASS_THRU_SCSI_REQUEST_PACKET*)WorkingBuffer;

  //
  // Convert EFI1.0 PassThru packet to UEFI2.0 SCSI IO Packet.
  //
  PassThruToScsiioPacket(ScsiPacket, Packet);

  //
  // After converting EFI1.0 PassThru Packet back to UEFI2.0 SCSI IO Packet,
  // free WorkingBuffer.
  //
  gBS->FreePool(WorkingBuffer);

  //
  // Signal Event to tell caller to pick up UEFI2.0 SCSI IO Packet.
  //
  CallerEvent = PassData->Data2;
  gBS->CloseEvent(Event);
  gBS->SignalEvent(CallerEvent);
}