audk/EdkModulePkg/Bus/Pci/PciBus/Dxe/PciEnumeratorSupport.c

/*++

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:

  PciEnumeratorSupport.c
  
Abstract:

  PCI Bus Driver

Revision History

--*/

#include "pcibus.h"
#include "PciEnumeratorSupport.h"
#include "PciCommand.h"
#include "PciIo.h"

EFI_STATUS
PciDevicePresent (
  IN EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL  *PciRootBridgeIo,
  PCI_TYPE00                          *Pci,
  UINT8                               Bus,
  UINT8                               Device,
  UINT8                               Func
  )
/*++

Routine Description:

  This routine is used to check whether the pci device is present

Arguments:

Returns:

  None

--*/
// TODO:    PciRootBridgeIo - add argument and description to function comment
// TODO:    Pci - add argument and description to function comment
// TODO:    Bus - add argument and description to function comment
// TODO:    Device - add argument and description to function comment
// TODO:    Func - add argument and description to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
// TODO:    EFI_NOT_FOUND - add return value to function comment
{
  UINT64      Address;
  EFI_STATUS  Status;

  //
  // Create PCI address map in terms of Bus, Device and Func
  //
  Address = EFI_PCI_ADDRESS (Bus, Device, Func, 0);

  //
  // Read the Vendor Id register
  //
  Status = PciRootBridgeIo->Pci.Read (
                                  PciRootBridgeIo,
                                  EfiPciWidthUint32,
                                  Address,
                                  1,
                                  Pci
                                  );

  if (!EFI_ERROR (Status) && (Pci->Hdr).VendorId != 0xffff) {

    //
    // Read the entire config header for the device
    //

    Status = PciRootBridgeIo->Pci.Read (
                                    PciRootBridgeIo,
                                    EfiPciWidthUint32,
                                    Address,
                                    sizeof (PCI_TYPE00) / sizeof (UINT32),
                                    Pci
                                    );

    return EFI_SUCCESS;
  }

  return EFI_NOT_FOUND;
}

EFI_STATUS
PciPciDeviceInfoCollector (
  IN PCI_IO_DEVICE                      *Bridge,
  UINT8                                 StartBusNumber
  )
/*++

Routine Description:

Arguments:

Returns:

  None

--*/
// TODO:    Bridge - add argument and description to function comment
// TODO:    StartBusNumber - add argument and description to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  EFI_STATUS          Status;
  PCI_TYPE00          Pci;
  UINT8               Device;
  UINT8               Func;
  UINT8               SecBus;
  PCI_IO_DEVICE       *PciIoDevice;
  EFI_PCI_IO_PROTOCOL *PciIo;

  Status  = EFI_SUCCESS;
  SecBus  = 0;

  for (Device = 0; Device <= PCI_MAX_DEVICE; Device++) {

    for (Func = 0; Func <= PCI_MAX_FUNC; Func++) {

      //
      // Check to see whether PCI device is present
      //

      Status = PciDevicePresent (
                Bridge->PciRootBridgeIo,
                &Pci,
                (UINT8) StartBusNumber,
                (UINT8) Device,
                (UINT8) Func
                );

      if (!EFI_ERROR (Status)) {

        //
        // Call back to host bridge function
        //
        PreprocessController (Bridge, (UINT8) StartBusNumber, Device, Func, EfiPciBeforeResourceCollection);

        //
        // Collect all the information about the PCI device discovered
        //
        Status = PciSearchDevice (
                  Bridge,
                  &Pci,
                  (UINT8) StartBusNumber,
                  Device,
                  Func,
                  &PciIoDevice
                  );

        //
        // Recursively scan PCI busses on the other side of PCI-PCI bridges
        //
        //

        if (!EFI_ERROR (Status) && (IS_PCI_BRIDGE (&Pci) || IS_CARDBUS_BRIDGE (&Pci))) {

          //
          // If it is PPB, we need to get the secondary bus to continue the enumeration
          //
          PciIo   = &(PciIoDevice->PciIo);

          Status  = PciIo->Pci.Read (PciIo, EfiPciIoWidthUint8, 0x19, 1, &SecBus);

          if (EFI_ERROR (Status)) {
            return Status;
          }
              
          //
          // Get resource padding for PPB
          //
          GetResourcePaddingPpb (PciIoDevice);

          //
          // Deep enumerate the next level bus
          //
          Status = PciPciDeviceInfoCollector (
                    PciIoDevice,
                    (UINT8) (SecBus)
                    );

        }

        if (Func == 0 && !IS_PCI_MULTI_FUNC (&Pci)) {

          //
          // Skip sub functions, this is not a multi function device
          //
          Func = PCI_MAX_FUNC;
        }
      }

    }
  }

  return EFI_SUCCESS;
}

EFI_STATUS
PciSearchDevice (
  IN  PCI_IO_DEVICE                         *Bridge,
  IN  PCI_TYPE00                            *Pci,
  IN  UINT8                                 Bus,
  IN  UINT8                                 Device,
  IN  UINT8                                 Func,
  OUT PCI_IO_DEVICE                         **PciDevice
  )
/*++

Routine Description:

  Search required device.

Arguments:

  Bridge     - A pointer to the PCI_IO_DEVICE.
  Pci        - A pointer to the PCI_TYPE00.
  Bus        - Bus number.
  Device     - Device number.
  Func       - Function number.
  PciDevice  - The Required pci device.

Returns:

  Status code.

--*/
// TODO:    EFI_OUT_OF_RESOURCES - add return value to function comment
// TODO:    EFI_OUT_OF_RESOURCES - add return value to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  PCI_IO_DEVICE *PciIoDevice;

  PciIoDevice = NULL;

  if (!IS_PCI_BRIDGE (Pci)) {

    if (IS_CARDBUS_BRIDGE (Pci)) {
      PciIoDevice = GatherP2CInfo (
                      Bridge,
                      Pci,
                      Bus,
                      Device,
                      Func
                      );
      if ((PciIoDevice != NULL) && gFullEnumeration) {
        InitializeP2C (PciIoDevice);      
      }
    } else {

      //
      // Create private data for Pci Device
      //
      PciIoDevice = GatherDeviceInfo (
                      Bridge,
                      Pci,
                      Bus,
                      Device,
                      Func
                      );

    }

  } else {

    //
    // Create private data for PPB
    //
    PciIoDevice = GatherPpbInfo (
                    Bridge,
                    Pci,
                    Bus,
                    Device,
                    Func
                    );

    //
    // Special initialization for PPB including making the PPB quiet
    //
    if ((PciIoDevice != NULL) && gFullEnumeration) {
      InitializePpb (PciIoDevice);
    }
  }

  if (!PciIoDevice) {
    return EFI_OUT_OF_RESOURCES;
  }
  
  //
  // Update the bar information for this PCI device so as to support some specific device
  //
  UpdatePciInfo (PciIoDevice);

  if (PciIoDevice->DevicePath == NULL) {
    return EFI_OUT_OF_RESOURCES;
  }
  
  //
  // Detect this function has option rom
  //
  if (gFullEnumeration) {

    if (!IS_CARDBUS_BRIDGE (Pci)) {

      GetOpRomInfo (PciIoDevice);

    }

    ResetPowerManagementFeature (PciIoDevice);

  }
 
  //
  // Insert it into a global tree for future reference
  //
  InsertPciDevice (Bridge, PciIoDevice);

  //
  // Determine PCI device attributes
  //

  if (PciDevice != NULL) {
    *PciDevice = PciIoDevice;
  }

  return EFI_SUCCESS;
}

PCI_IO_DEVICE *
GatherDeviceInfo (
  IN PCI_IO_DEVICE                    *Bridge,
  IN PCI_TYPE00                       *Pci,
  UINT8                               Bus,
  UINT8                               Device,
  UINT8                               Func
  )
/*++

Routine Description:

Arguments:

Returns:

  None

--*/
// TODO:    Bridge - add argument and description to function comment
// TODO:    Pci - add argument and description to function comment
// TODO:    Bus - add argument and description to function comment
// TODO:    Device - add argument and description to function comment
// TODO:    Func - add argument and description to function comment
{
  UINTN                           Offset;
  UINTN                           BarIndex;
  PCI_IO_DEVICE                   *PciIoDevice;
  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL *PciRootBridgeIo;

  PciRootBridgeIo = Bridge->PciRootBridgeIo;
  PciIoDevice = CreatePciIoDevice (
                  PciRootBridgeIo,
                  Pci,
                  Bus,
                  Device,
                  Func
                  );

  if (!PciIoDevice) {
    return NULL;
  }

  //
  // Create a device path for this PCI device and store it into its private data
  //
  CreatePciDevicePath (
    Bridge->DevicePath,
    PciIoDevice
    );

  //
  // If it is a full enumeration, disconnect the device in advance
  //
  if (gFullEnumeration) {

    PciDisableCommandRegister (PciIoDevice, EFI_PCI_COMMAND_BITS_OWNED);

  }

  //
  // Start to parse the bars
  //
  for (Offset = 0x10, BarIndex = 0; Offset <= 0x24; BarIndex++) {
    Offset = PciParseBar (PciIoDevice, Offset, BarIndex);
  }

  return PciIoDevice;
}

PCI_IO_DEVICE *
GatherPpbInfo (
  IN PCI_IO_DEVICE                    *Bridge,
  IN PCI_TYPE00                       *Pci,
  UINT8                               Bus,
  UINT8                               Device,
  UINT8                               Func
  )
/*++

Routine Description:

Arguments:

Returns:

  None

--*/
// TODO:    Bridge - add argument and description to function comment
// TODO:    Pci - add argument and description to function comment
// TODO:    Bus - add argument and description to function comment
// TODO:    Device - add argument and description to function comment
// TODO:    Func - add argument and description to function comment
{
  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL *PciRootBridgeIo;
  PCI_IO_DEVICE                   *PciIoDevice;
  EFI_STATUS                      Status;
  UINT32                          Value;
  EFI_PCI_IO_PROTOCOL             *PciIo;
  UINT8                           Temp;

  PciRootBridgeIo = Bridge->PciRootBridgeIo;
  PciIoDevice = CreatePciIoDevice (
                  PciRootBridgeIo,
                  Pci,
                  Bus,
                  Device,
                  Func
                  );

  if (!PciIoDevice) {
    return NULL;
  }
  
  //
  // Create a device path for this PCI device and store it into its private data
  //
  CreatePciDevicePath (
    Bridge->DevicePath,
    PciIoDevice
    );

  if (gFullEnumeration) {
    PciDisableCommandRegister (PciIoDevice, EFI_PCI_COMMAND_BITS_OWNED);

    //
    // Initalize the bridge control register
    //
    PciDisableBridgeControlRegister (PciIoDevice, EFI_PCI_BRIDGE_CONTROL_BITS_OWNED);

  }

  //
  // PPB can have two BARs
  //
  if (PciParseBar (PciIoDevice, 0x10, PPB_BAR_0) == 0x14) {
    //
    // Not 64-bit bar
    //
    PciParseBar (PciIoDevice, 0x14, PPB_BAR_1);
  }

  PciIo = &PciIoDevice->PciIo;

  //
  // Test whether it support 32 decode or not
  //
  PciIo->Pci.Read (PciIo, EfiPciIoWidthUint8, 0x1C, 1, &Temp);
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint8, 0x1C, 1, &gAllOne);
  PciIo->Pci.Read (PciIo, EfiPciIoWidthUint8, 0x1C, 1, &Value);
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint8, 0x1C, 1, &Temp);

  if (Value) {
    if (Value & 0x01) {
      PciIoDevice->Decodes |= EFI_BRIDGE_IO32_DECODE_SUPPORTED;
    } else {
      PciIoDevice->Decodes |= EFI_BRIDGE_IO16_DECODE_SUPPORTED;
    }
  }

  Status = BarExisted (
            PciIoDevice,
            0x24,
            NULL,
            NULL
            );

  //
  // test if it supports 64 memory or not
  //
  if (!EFI_ERROR (Status)) {

    Status = BarExisted (
              PciIoDevice,
              0x28,
              NULL,
              NULL
              );

    if (!EFI_ERROR (Status)) {
      PciIoDevice->Decodes |= EFI_BRIDGE_PMEM32_DECODE_SUPPORTED;
      PciIoDevice->Decodes |= EFI_BRIDGE_PMEM64_DECODE_SUPPORTED;
    } else {
      PciIoDevice->Decodes |= EFI_BRIDGE_PMEM32_DECODE_SUPPORTED;
    }
  }

  //
  // Memory 32 code is required for ppb
  //
  PciIoDevice->Decodes |= EFI_BRIDGE_MEM32_DECODE_SUPPORTED;

  GetResourcePaddingPpb (PciIoDevice);

  return PciIoDevice;
}

PCI_IO_DEVICE *
GatherP2CInfo (
  IN PCI_IO_DEVICE                    *Bridge,
  IN PCI_TYPE00                       *Pci,
  UINT8                               Bus,
  UINT8                               Device,
  UINT8                               Func
  )
/*++

Routine Description:

Arguments:

Returns:

  None

--*/
// TODO:    Bridge - add argument and description to function comment
// TODO:    Pci - add argument and description to function comment
// TODO:    Bus - add argument and description to function comment
// TODO:    Device - add argument and description to function comment
// TODO:    Func - add argument and description to function comment
{
  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL *PciRootBridgeIo;
  PCI_IO_DEVICE                   *PciIoDevice;

  PciRootBridgeIo = Bridge->PciRootBridgeIo;
  PciIoDevice = CreatePciIoDevice (
                  PciRootBridgeIo,
                  Pci,
                  Bus,
                  Device,
                  Func
                  );

  if (!PciIoDevice) {
    return NULL;
  }

  //
  // Create a device path for this PCI device and store it into its private data
  //
  CreatePciDevicePath (
    Bridge->DevicePath,
    PciIoDevice
    );

  if (gFullEnumeration) {
    PciDisableCommandRegister (PciIoDevice, EFI_PCI_COMMAND_BITS_OWNED);

    //
    // Initalize the bridge control register
    //
    PciDisableBridgeControlRegister (PciIoDevice, EFI_PCCARD_BRIDGE_CONTROL_BITS_OWNED);

  }
  //
  // P2C only has one bar that is in 0x10
  //
  PciParseBar (PciIoDevice, 0x10, P2C_BAR_0);

  //
  // Read PciBar information from the bar register
  //
  GetBackPcCardBar (PciIoDevice);
  PciIoDevice->Decodes = EFI_BRIDGE_MEM32_DECODE_SUPPORTED  |
                         EFI_BRIDGE_PMEM32_DECODE_SUPPORTED |
                         EFI_BRIDGE_IO32_DECODE_SUPPORTED;

  return PciIoDevice;
}

EFI_DEVICE_PATH_PROTOCOL *
CreatePciDevicePath (
  IN  EFI_DEVICE_PATH_PROTOCOL *ParentDevicePath,
  IN  PCI_IO_DEVICE            *PciIoDevice
  )
/*++

Routine Description:

Arguments:

Returns:

  None

--*/
// TODO:    ParentDevicePath - add argument and description to function comment
// TODO:    PciIoDevice - add argument and description to function comment
{

  PCI_DEVICE_PATH PciNode;

  //
  // Create PCI device path
  //
  PciNode.Header.Type     = HARDWARE_DEVICE_PATH;
  PciNode.Header.SubType  = HW_PCI_DP;
  SetDevicePathNodeLength (&PciNode.Header, sizeof (PciNode));

  PciNode.Device          = PciIoDevice->DeviceNumber;
  PciNode.Function        = PciIoDevice->FunctionNumber;
  PciIoDevice->DevicePath = AppendDevicePathNode (ParentDevicePath, &PciNode.Header);

  return PciIoDevice->DevicePath;
}

EFI_STATUS
BarExisted (
  IN PCI_IO_DEVICE *PciIoDevice,
  IN UINTN         Offset,
  OUT UINT32       *BarLengthValue,
  OUT UINT32       *OriginalBarValue
  )
/*++

Routine Description:

  Check the bar is existed or not.

Arguments:

  PciIoDevice       - A pointer to the PCI_IO_DEVICE.
  Offset            - The offset.
  BarLengthValue    - The bar length value.
  OriginalBarValue  - The original bar value.

Returns:

  EFI_NOT_FOUND     - The bar don't exist.
  EFI_SUCCESS       - The bar exist.

--*/
{
  EFI_PCI_IO_PROTOCOL *PciIo;
  UINT32              OriginalValue;
  UINT32              Value;
  EFI_TPL             OldTpl;

  PciIo = &PciIoDevice->PciIo;

  //
  // Preserve the original value
  //

  PciIo->Pci.Read (PciIo, EfiPciIoWidthUint32, (UINT8) Offset, 1, &OriginalValue);

  //
  // Raise TPL to high level to disable timer interrupt while the BAR is probed
  //
  OldTpl = gBS->RaiseTPL (EFI_TPL_HIGH_LEVEL);

  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint32, (UINT8) Offset, 1, &gAllOne);
  PciIo->Pci.Read (PciIo, EfiPciIoWidthUint32, (UINT8) Offset, 1, &Value);

  //
  // Write back the original value
  //
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint32, (UINT8) Offset, 1, &OriginalValue);

  //
  // Restore TPL to its original level
  //
  gBS->RestoreTPL (OldTpl);

  if (BarLengthValue != NULL) {
    *BarLengthValue = Value;
  }

  if (OriginalBarValue != NULL) {
    *OriginalBarValue = OriginalValue;
  }

  if (Value == 0) {
    return EFI_NOT_FOUND;
  } else {
    return EFI_SUCCESS;
  }
}

EFI_STATUS
PciTestSupportedAttribute (
  IN PCI_IO_DEVICE                      *PciIoDevice,
  IN UINT16                             *Command,
  IN UINT16                             *BridgeControl,
  IN UINT16                             *OldCommand,
  IN UINT16                             *OldBridgeControl
  )
/*++

Routine Description:

Arguments:

Returns:

  None

--*/
// TODO:    PciIoDevice - add argument and description to function comment
// TODO:    Command - add argument and description to function comment
// TODO:    BridgeControl - add argument and description to function comment
// TODO:    OldCommand - add argument and description to function comment
// TODO:    OldBridgeControl - add argument and description to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  EFI_TPL OldTpl;

  //
  // Preserve the original value
  //
  PciReadCommandRegister (PciIoDevice, OldCommand);

  //
  // Raise TPL to high level to disable timer interrupt while the BAR is probed
  //
  OldTpl = gBS->RaiseTPL (EFI_TPL_HIGH_LEVEL);

  PciSetCommandRegister (PciIoDevice, *Command);
  PciReadCommandRegister (PciIoDevice, Command);

  //
  // Write back the original value
  //
  PciSetCommandRegister (PciIoDevice, *OldCommand);

  //
  // Restore TPL to its original level
  //
  gBS->RestoreTPL (OldTpl);

  if (IS_PCI_BRIDGE (&PciIoDevice->Pci) || IS_CARDBUS_BRIDGE (&PciIoDevice->Pci)) {
    
    //
    // Preserve the original value
    //
    PciReadBridgeControlRegister (PciIoDevice, OldBridgeControl);

    //
    // Raise TPL to high level to disable timer interrupt while the BAR is probed
    //
    OldTpl = gBS->RaiseTPL (EFI_TPL_HIGH_LEVEL);

    PciSetBridgeControlRegister (PciIoDevice, *BridgeControl);
    PciReadBridgeControlRegister (PciIoDevice, BridgeControl);

    //
    // Write back the original value
    //
    PciSetBridgeControlRegister (PciIoDevice, *OldBridgeControl);

    //
    // Restore TPL to its original level
    //
    gBS->RestoreTPL (OldTpl);

  } else {
    *OldBridgeControl = 0;
    *BridgeControl    = 0;
  }

  return EFI_SUCCESS;
}

EFI_STATUS
PciSetDeviceAttribute (
  IN PCI_IO_DEVICE                      *PciIoDevice,
  IN UINT16                             Command,
  IN UINT16                             BridgeControl,
  IN UINTN                              Option
  )
/*++

  Routine Description:
    Set the supported or current attributes of a PCI device    

  Arguments:
    PciIoDevice   - Structure pointer for PCI device.
    Command       - Command register value.
    BridgeControl - Bridge control value for PPB or P2C.
    Option        - Make a choice of EFI_SET_SUPPORTS or EFI_SET_ATTRIBUTES.

  Returns:    

--*/

/*++

Routine Description:

  

Arguments:
 
  
Returns:
  
  EFI_SUCCESS   Always success
  

--*/
{
  UINT64  Attributes;

  Attributes = 0;

  if (Command & EFI_PCI_COMMAND_IO_SPACE) {
    Attributes |= EFI_PCI_IO_ATTRIBUTE_IO;
  }

  if (Command & EFI_PCI_COMMAND_MEMORY_SPACE) {
    Attributes |= EFI_PCI_IO_ATTRIBUTE_MEMORY;
  }

  if (Command & EFI_PCI_COMMAND_BUS_MASTER) {
    Attributes |= EFI_PCI_IO_ATTRIBUTE_BUS_MASTER;
  }

  if (Command & EFI_PCI_COMMAND_VGA_PALETTE_SNOOP) {
    Attributes |= EFI_PCI_IO_ATTRIBUTE_VGA_PALETTE_IO;
  }

  if (BridgeControl & EFI_PCI_BRIDGE_CONTROL_ISA) {
    Attributes |= EFI_PCI_IO_ATTRIBUTE_ISA_IO;
  }

  if (BridgeControl & EFI_PCI_BRIDGE_CONTROL_VGA) {
    Attributes |= EFI_PCI_IO_ATTRIBUTE_VGA_IO;
    Attributes |= EFI_PCI_IO_ATTRIBUTE_VGA_MEMORY;
    Attributes |= EFI_PCI_IO_ATTRIBUTE_VGA_PALETTE_IO;
  }

  if (BridgeControl & EFI_PCI_BRIDGE_CONTROL_VGA_16) {
    Attributes |= EFI_PCI_IO_ATTRIBUTE_VGA_IO_16;
    Attributes |= EFI_PCI_IO_ATTRIBUTE_VGA_PALETTE_IO_16;
  }

  if (Option == EFI_SET_SUPPORTS) {

    Attributes |= EFI_PCI_IO_ATTRIBUTE_MEMORY_WRITE_COMBINE | 
                  EFI_PCI_IO_ATTRIBUTE_MEMORY_CACHED        |
                  EFI_PCI_IO_ATTRIBUTE_MEMORY_DISABLE       |
                  EFI_PCI_IO_ATTRIBUTE_EMBEDDED_DEVICE      |
                  EFI_PCI_IO_ATTRIBUTE_EMBEDDED_ROM         |
                  EFI_PCI_IO_ATTRIBUTE_DUAL_ADDRESS_CYCLE;

    if (Attributes & EFI_PCI_IO_ATTRIBUTE_IO) {
      Attributes |= EFI_PCI_IO_ATTRIBUTE_ISA_MOTHERBOARD_IO;
      Attributes |= EFI_PCI_IO_ATTRIBUTE_ISA_IO;
    }

    if (IS_PCI_BRIDGE (&PciIoDevice->Pci) || IS_CARDBUS_BRIDGE (&PciIoDevice->Pci)) {
      //
      // For bridge, it should support IDE attributes
      //
      Attributes |= EFI_PCI_IO_ATTRIBUTE_IDE_SECONDARY_IO;
      Attributes |= EFI_PCI_IO_ATTRIBUTE_IDE_PRIMARY_IO;
    } else {

      if (IS_PCI_IDE (&PciIoDevice->Pci)) {
        Attributes |= EFI_PCI_IO_ATTRIBUTE_IDE_SECONDARY_IO;
        Attributes |= EFI_PCI_IO_ATTRIBUTE_IDE_PRIMARY_IO;
      }

      if (IS_PCI_VGA (&PciIoDevice->Pci)) {
        Attributes |= EFI_PCI_IO_ATTRIBUTE_VGA_MEMORY;
        Attributes |= EFI_PCI_IO_ATTRIBUTE_VGA_IO;
      }
    }

    PciIoDevice->Supports = Attributes;
    PciIoDevice->Supports &= ( (PciIoDevice->Parent->Supports) | \
                               EFI_PCI_IO_ATTRIBUTE_IO | EFI_PCI_IO_ATTRIBUTE_MEMORY | \
                               EFI_PCI_IO_ATTRIBUTE_BUS_MASTER );

  } else {
    PciIoDevice->Attributes = Attributes;
  }

  return EFI_SUCCESS;
}

EFI_STATUS
GetFastBackToBackSupport (
  IN PCI_IO_DEVICE                      *PciIoDevice,
  IN UINT8                              StatusIndex
  )
/*++

Routine Description:
 
  Determine if the device can support Fast Back to Back attribute

Arguments:

Returns:

  None

--*/
// TODO:    PciIoDevice - add argument and description to function comment
// TODO:    StatusIndex - add argument and description to function comment
// TODO:    EFI_UNSUPPORTED - add return value to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
// TODO:    EFI_UNSUPPORTED - add return value to function comment
{
  EFI_PCI_IO_PROTOCOL *PciIo;
  EFI_STATUS          Status;
  UINT32              StatusRegister;

  //
  // Read the status register
  //
  PciIo   = &PciIoDevice->PciIo;
  Status  = PciIo->Pci.Read (PciIo, EfiPciIoWidthUint16, StatusIndex, 1, &StatusRegister);
  if (EFI_ERROR (Status)) {
    return EFI_UNSUPPORTED;
  }
  
  //
  // Check the Fast B2B bit
  //
  if (StatusRegister & EFI_PCI_FAST_BACK_TO_BACK_CAPABLE) {
    return EFI_SUCCESS;
  } else {
    return EFI_UNSUPPORTED;
  }

}

STATIC
EFI_STATUS
ProcessOptionRomLight (
  IN PCI_IO_DEVICE                      *PciIoDevice
  )
/*++

Routine Description:
 
  Process the option ROM for all the children of the specified parent PCI device.
  It can only be used after the first full Option ROM process.

Arguments:

Returns:

  None

--*/
// TODO:    PciIoDevice - add argument and description to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  PCI_IO_DEVICE   *Temp;
  LIST_ENTRY      *CurrentLink;

  //
  // For RootBridge, PPB , P2C, go recursively to traverse all its children
  //
  CurrentLink = PciIoDevice->ChildList.ForwardLink;
  while (CurrentLink && CurrentLink != &PciIoDevice->ChildList) {

    Temp = PCI_IO_DEVICE_FROM_LINK (CurrentLink);

    if (!IsListEmpty (&Temp->ChildList)) {
      ProcessOptionRomLight (Temp);
    }

    PciRomGetImageMapping (Temp);
    CurrentLink = CurrentLink->ForwardLink;
  }

  return EFI_SUCCESS;
}

EFI_STATUS
DetermineDeviceAttribute (
  IN PCI_IO_DEVICE                      *PciIoDevice
  )
/*++

Routine Description:
 
  Determine the related attributes of all devices under a Root Bridge

Arguments:

Returns:

  None

--*/
// TODO:    PciIoDevice - add argument and description to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  UINT16          Command;
  UINT16          BridgeControl;
  UINT16          OldCommand;
  UINT16          OldBridgeControl;
  BOOLEAN         FastB2BSupport;

  /*
  UINT8  IdePI;
  EFI_PCI_IO_PROTOCOL   *PciIo;
  */
  PCI_IO_DEVICE   *Temp;
  LIST_ENTRY      *CurrentLink;
  EFI_STATUS      Status;

  //
  // For Root Bridge, just copy it by RootBridgeIo proctocol
  // so as to keep consistent with the actual attribute
  //
  if (!PciIoDevice->Parent) {
    Status = PciIoDevice->PciRootBridgeIo->GetAttributes (
                                            PciIoDevice->PciRootBridgeIo,
                                            &PciIoDevice->Supports,
                                            &PciIoDevice->Attributes
                                            );
    if (EFI_ERROR (Status)) {
      return Status;
    }
  } else {
  
    //
    // Set the attributes to be checked for common PCI devices and PPB or P2C
    // Since some devices only support part of them, it is better to set the
    // attribute according to its command or bridge control register
    //
    Command = EFI_PCI_COMMAND_IO_SPACE     |
              EFI_PCI_COMMAND_MEMORY_SPACE |
              EFI_PCI_COMMAND_BUS_MASTER   |
              EFI_PCI_COMMAND_VGA_PALETTE_SNOOP;

    BridgeControl = EFI_PCI_BRIDGE_CONTROL_ISA | EFI_PCI_BRIDGE_CONTROL_VGA | EFI_PCI_BRIDGE_CONTROL_VGA_16;

    //
    // Test whether the device can support attributes above
    //
    PciTestSupportedAttribute (PciIoDevice, &Command, &BridgeControl, &OldCommand, &OldBridgeControl);

    //
    // Set the supported attributes for specified PCI device
    //
    PciSetDeviceAttribute (PciIoDevice, Command, BridgeControl, EFI_SET_SUPPORTS);

    //
    // Set the current attributes for specified PCI device
    //
    PciSetDeviceAttribute (PciIoDevice, OldCommand, OldBridgeControl, EFI_SET_ATTRIBUTES);

    //
    // Enable other supported attributes but not defined in PCI_IO_PROTOCOL
    //
    PciEnableCommandRegister (PciIoDevice, EFI_PCI_COMMAND_MEMORY_WRITE_AND_INVALIDATE);

    //
    // Enable IDE native mode
    //
    /*
    if (IS_PCI_IDE(&PciIoDevice->Pci)) {

      PciIo = &PciIoDevice->PciIo;  

      PciIo->Pci.Read (
                              PciIo, 
                              EfiPciIoWidthUint8, 
                              0x09, 
                              1, 
                              &IdePI
                              );
      
      //
      // Set native mode if it can be supported
      //      
      IdePI |= (((IdePI & 0x0F) >> 1) & 0x05);

      PciIo->Pci.Write (
                              PciIo, 
                              EfiPciIoWidthUint8, 
                              0x09, 
                              1, 
                              &IdePI
                              );  
    
    }  
    */
  }

  FastB2BSupport = TRUE;

  //
  // P2C can not support FB2B on the secondary side
  //
  if (IS_CARDBUS_BRIDGE (&PciIoDevice->Pci)) {
    FastB2BSupport = FALSE;
  }
  
  //
  // For RootBridge, PPB , P2C, go recursively to traverse all its children
  //
  CurrentLink = PciIoDevice->ChildList.ForwardLink;
  while (CurrentLink && CurrentLink != &PciIoDevice->ChildList) {

    Temp    = PCI_IO_DEVICE_FROM_LINK (CurrentLink);
    Status  = DetermineDeviceAttribute (Temp);
    if (EFI_ERROR (Status)) {
      return Status;
    }
    //
    // Detect Fast Bact to Bact support for the device under the bridge
    //
    Status = GetFastBackToBackSupport (Temp, PCI_PRIMARY_STATUS_OFFSET);
    if (FastB2BSupport && EFI_ERROR (Status)) {
      FastB2BSupport = FALSE;
    }

    CurrentLink = CurrentLink->ForwardLink;
  }
  //
  // Set or clear Fast Back to Back bit for the whole bridge
  //
  if (!IsListEmpty (&PciIoDevice->ChildList)) {

    if (IS_PCI_BRIDGE (&PciIoDevice->Pci)) {

      Status = GetFastBackToBackSupport (PciIoDevice, PCI_BRIDGE_STATUS_REGISTER_OFFSET);

      if (EFI_ERROR (Status) || (!FastB2BSupport)) {
        FastB2BSupport = FALSE;
        PciDisableBridgeControlRegister (PciIoDevice, EFI_PCI_BRIDGE_CONTROL_FAST_BACK_TO_BACK);
      } else {
        PciEnableBridgeControlRegister (PciIoDevice, EFI_PCI_BRIDGE_CONTROL_FAST_BACK_TO_BACK);
      }
    }

    CurrentLink = PciIoDevice->ChildList.ForwardLink;
    while (CurrentLink && CurrentLink != &PciIoDevice->ChildList) {
      Temp = PCI_IO_DEVICE_FROM_LINK (CurrentLink);
      if (FastB2BSupport) {
        PciEnableCommandRegister (Temp, EFI_PCI_COMMAND_FAST_BACK_TO_BACK);
      } else {
        PciDisableCommandRegister (Temp, EFI_PCI_COMMAND_FAST_BACK_TO_BACK);
      }

      CurrentLink = CurrentLink->ForwardLink;
    }
  }
  //
  // End for IsListEmpty
  //
  return EFI_SUCCESS;
}

EFI_STATUS
UpdatePciInfo (
  IN PCI_IO_DEVICE  *PciIoDevice
  )
/*++

Routine Description:

  This routine is used to update the bar information for those incompatible PCI device

Arguments:

Returns:

  None

--*/
// TODO:    PciIoDevice - add argument and description to function comment
// TODO:    EFI_UNSUPPORTED - add return value to function comment
{
  EFI_STATUS                        Status;
  UINTN                             BarIndex;
  UINTN                             BarEndIndex;
  BOOLEAN                           SetFlag;
  VOID                              *Configuration;
  EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *Ptr;

  Configuration = NULL;

  //
  // It can only be supported after the Incompatible PCI Device
  // Support Protocol has been installed
  //
  if (gEfiIncompatiblePciDeviceSupport == NULL) {

    Status = gBS->LocateProtocol (
                    &gEfiIncompatiblePciDeviceSupportProtocolGuid,
                    NULL,
                    (VOID **) &gEfiIncompatiblePciDeviceSupport
                    );
    if (EFI_ERROR (Status)) {
      return EFI_UNSUPPORTED;
    }
  }
  
  //
  // Check whether the device belongs to incompatible devices or not
  // If it is , then get its special requirement in the ACPI table
  //
  Status = gEfiIncompatiblePciDeviceSupport->CheckDevice (
                                              gEfiIncompatiblePciDeviceSupport,
                                              PciIoDevice->Pci.Hdr.VendorId,
                                              PciIoDevice->Pci.Hdr.DeviceId,
                                              PciIoDevice->Pci.Hdr.RevisionID,
                                              PciIoDevice->Pci.Device.SubsystemVendorID,
                                              PciIoDevice->Pci.Device.SubsystemID,
                                              &Configuration
                                              );

  if (EFI_ERROR (Status)) {
    return Status;
  }
  
  //
  // Update PCI device information from the ACPI table
  //
  Ptr = (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *) Configuration;

  while (Ptr->Desc != ACPI_END_TAG_DESCRIPTOR) {

    if (Ptr->Desc != ACPI_ADDRESS_SPACE_DESCRIPTOR) {
      //
      // The format is not support
      //
      break;
    }

    BarIndex    = (UINTN) Ptr->AddrTranslationOffset;
    BarEndIndex = BarIndex;

    //
    // Update all the bars in the device
    //
    if (BarIndex == PCI_BAR_ALL) {
      BarIndex    = 0;
      BarEndIndex = PCI_MAX_BAR - 1;
    }

    if (BarIndex >= PCI_MAX_BAR) {
      Ptr++;
      continue;
    }

    for (; BarIndex <= BarEndIndex; BarIndex++) {
      SetFlag = FALSE;
      switch (Ptr->ResType) {
      case ACPI_ADDRESS_SPACE_TYPE_MEM:
          
        //
        // Make sure the bar is memory type
        //
        if (CheckBarType (PciIoDevice, (UINT8) BarIndex, PciBarTypeMem)) {
          SetFlag = TRUE;
        }
        break;

      case ACPI_ADDRESS_SPACE_TYPE_IO:
          
        //
        // Make sure the bar is IO type
        //
        if (CheckBarType (PciIoDevice, (UINT8) BarIndex, PciBarTypeIo)) {
          SetFlag = TRUE;
        }
        break;
      }

      if (SetFlag) {
        
        //
        // Update the new alignment for the device
        //
        SetNewAlign (&(PciIoDevice->PciBar[BarIndex].Alignment), Ptr->AddrRangeMax);

        //
        // Update the new length for the device
        //
        if (Ptr->AddrLen != PCI_BAR_NOCHANGE) {
          PciIoDevice->PciBar[BarIndex].Length = Ptr->AddrLen;
        }
      }
    }

    Ptr++;
  }

  gBS->FreePool (Configuration);
  return Status;

}

VOID
SetNewAlign (
  IN UINT64 *Alignment,
  IN UINT64 NewAlignment
  )
/*++

Routine Description:

  This routine will update the alignment with the new alignment

Arguments:

Returns:

  None

--*/
// TODO:    Alignment - add argument and description to function comment
// TODO:    NewAlignment - add argument and description to function comment
{
  UINT64  OldAlignment;
  UINTN   ShiftBit;

  //
  // The new alignment is the same as the original,
  // so skip it
  //
  if (NewAlignment == PCI_BAR_OLD_ALIGN) {
    return ;
  }
  //
  // Check the validity of the parameter
  //
   if (NewAlignment != PCI_BAR_EVEN_ALIGN  && 
       NewAlignment != PCI_BAR_SQUAD_ALIGN &&
       NewAlignment != PCI_BAR_DQUAD_ALIGN ) {         
    *Alignment = NewAlignment;
    return ;
  }

  OldAlignment  = (*Alignment) + 1;
  ShiftBit      = 0;

  //
  // Get the first non-zero hex value of the length
  //
  while ((OldAlignment & 0x0F) == 0x00) {
    OldAlignment = RShiftU64 (OldAlignment, 4);
    ShiftBit += 4;
  }
   
  //
  // Adjust the alignment to even, quad or double quad boundary
  //
  if (NewAlignment == PCI_BAR_EVEN_ALIGN) {
    if (OldAlignment & 0x01) {
      OldAlignment = OldAlignment + 2 - (OldAlignment & 0x01);
    }
  } else if (NewAlignment == PCI_BAR_SQUAD_ALIGN) {
    if (OldAlignment & 0x03) {
      OldAlignment = OldAlignment + 4 - (OldAlignment & 0x03);
    }
  } else if (NewAlignment == PCI_BAR_DQUAD_ALIGN) {
    if (OldAlignment & 0x07) {
      OldAlignment = OldAlignment + 8 - (OldAlignment & 0x07);
    }
  }
   
  //
  // Update the old value
  //
  NewAlignment  = LShiftU64 (OldAlignment, ShiftBit) - 1;
  *Alignment    = NewAlignment;

  return ;
}

UINTN
PciParseBar (
  IN PCI_IO_DEVICE  *PciIoDevice,
  IN UINTN          Offset,
  IN UINTN          BarIndex
  )
/*++

Routine Description:

Arguments:

Returns:

  None

--*/
// TODO:    PciIoDevice - add argument and description to function comment
// TODO:    Offset - add argument and description to function comment
// TODO:    BarIndex - add argument and description to function comment
{
  UINT32      Value;
  UINT32      OriginalValue;
  UINT32      Mask;
  UINT32      Data;
  UINT8       Index;
  EFI_STATUS  Status;

  OriginalValue = 0;
  Value         = 0;

  Status = BarExisted (
            PciIoDevice,
            Offset,
            &Value,
            &OriginalValue
            );

  if (EFI_ERROR (Status)) {
    PciIoDevice->PciBar[BarIndex].BaseAddress = 0;
    PciIoDevice->PciBar[BarIndex].Length      = 0;
    PciIoDevice->PciBar[BarIndex].Alignment   = 0;

    //
    // Some devices don't fully comply to PCI spec 2.2. So be to scan all the BARs anyway
    //
    PciIoDevice->PciBar[BarIndex].Offset = (UINT8) Offset;
    return Offset + 4;
  }

  PciIoDevice->PciBar[BarIndex].Offset = (UINT8) Offset;
  if (Value & 0x01) {
    //
    // Device I/Os
    //
    Mask = 0xfffffffc;

    if (Value & 0xFFFF0000) {
      //
      // It is a IO32 bar
      //
      PciIoDevice->PciBar[BarIndex].BarType   = PciBarTypeIo32;
      PciIoDevice->PciBar[BarIndex].Length    = ((~(Value & Mask)) + 1);
      PciIoDevice->PciBar[BarIndex].Alignment = PciIoDevice->PciBar[BarIndex].Length - 1;

    } else {
      //
      // It is a IO16 bar
      //
      PciIoDevice->PciBar[BarIndex].BarType   = PciBarTypeIo16;
      PciIoDevice->PciBar[BarIndex].Length    = 0x0000FFFF & ((~(Value & Mask)) + 1);
      PciIoDevice->PciBar[BarIndex].Alignment = PciIoDevice->PciBar[BarIndex].Length - 1;

    }
    //
    // Workaround. Some platforms inplement IO bar with 0 length
    // Need to treat it as no-bar
    //
    if (PciIoDevice->PciBar[BarIndex].Length == 0) {
      PciIoDevice->PciBar[BarIndex].BarType = (PCI_BAR_TYPE) 0;
    }

    PciIoDevice->PciBar[BarIndex].Prefetchable  = FALSE;
    PciIoDevice->PciBar[BarIndex].BaseAddress   = OriginalValue & Mask;

  } else {

    Mask  = 0xfffffff0;

    PciIoDevice->PciBar[BarIndex].BaseAddress = OriginalValue & Mask;

    switch (Value & 0x07) {

    //
    //memory space; anywhere in 32 bit address space
    //
    case 0x00:
      if (Value & 0x08) {
        PciIoDevice->PciBar[BarIndex].BarType = PciBarTypePMem32;
      } else {
        PciIoDevice->PciBar[BarIndex].BarType = PciBarTypeMem32;
      }

      PciIoDevice->PciBar[BarIndex].Length    = (~(Value & Mask)) + 1;
      PciIoDevice->PciBar[BarIndex].Alignment = PciIoDevice->PciBar[BarIndex].Length - 1;

      break;

    //
    // memory space; anywhere in 64 bit address space
    //
    case 0x04:
      if (Value & 0x08) {
        PciIoDevice->PciBar[BarIndex].BarType = PciBarTypePMem64;
      } else {
        PciIoDevice->PciBar[BarIndex].BarType = PciBarTypeMem64;
      }

      //
      // According to PCI 2.2,if the bar indicates a memory 64 decoding, next bar
      // is regarded as an extension for the first bar. As a result
      // the sizing will be conducted on combined 64 bit value
      // Here just store the masked first 32bit value for future size
      // calculation
      //
      PciIoDevice->PciBar[BarIndex].Length    = Value & Mask;
      PciIoDevice->PciBar[BarIndex].Alignment = PciIoDevice->PciBar[BarIndex].Length - 1;

      //
      // Increment the offset to point to next DWORD
      //
      Offset += 4;

      Status = BarExisted (
                PciIoDevice,
                Offset,
                &Value,
                &OriginalValue
                );

      if (EFI_ERROR (Status)) {
        return Offset + 4;
      }

      //
      // Fix the length to support some spefic 64 bit BAR
      //
      Data  = Value;
      Index = 0;
      for (Data = Value; Data != 0; Data >>= 1) {
      	Index ++;
      }
      Value |= ((UINT32)(-1) << Index); 

      //
      // Calculate the size of 64bit bar
      //
      PciIoDevice->PciBar[BarIndex].BaseAddress |= LShiftU64 ((UINT64) OriginalValue, 32);

      PciIoDevice->PciBar[BarIndex].Length    = PciIoDevice->PciBar[BarIndex].Length | LShiftU64 ((UINT64) Value, 32);
      PciIoDevice->PciBar[BarIndex].Length    = (~(PciIoDevice->PciBar[BarIndex].Length)) + 1;
      PciIoDevice->PciBar[BarIndex].Alignment = PciIoDevice->PciBar[BarIndex].Length - 1;

      break;

    //
    // reserved
    //
    default:
      PciIoDevice->PciBar[BarIndex].BarType   = PciBarTypeUnknown;
      PciIoDevice->PciBar[BarIndex].Length    = (~(Value & Mask)) + 1;
      PciIoDevice->PciBar[BarIndex].Alignment = PciIoDevice->PciBar[BarIndex].Length - 1;

      break;
    }
  }
  
  //
  // Check the length again so as to keep compatible with some special bars
  //
  if (PciIoDevice->PciBar[BarIndex].Length == 0) {
    PciIoDevice->PciBar[BarIndex].BarType     = PciBarTypeUnknown;
    PciIoDevice->PciBar[BarIndex].BaseAddress = 0;
    PciIoDevice->PciBar[BarIndex].Alignment   = 0;
  }
  
  //
  // Increment number of bar
  //
  return Offset + 4;
}

EFI_STATUS
InitializePciDevice (
  IN PCI_IO_DEVICE *PciIoDevice
  )
/*++

Routine Description:
 
  This routine is used to initialize the bar of a PCI device
  It can be called typically when a device is going to be rejected

Arguments:

Returns:

  None

--*/
// TODO:    PciIoDevice - add argument and description to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  EFI_PCI_IO_PROTOCOL *PciIo;
  UINT8               Offset;

  PciIo = &(PciIoDevice->PciIo);

  //
  // Put all the resource apertures
  // Resource base is set to all ones so as to indicate its resource
  // has not been alloacted
  //
  for (Offset = 0x10; Offset <= 0x24; Offset += sizeof (UINT32)) {
    PciIo->Pci.Write (PciIo, EfiPciIoWidthUint32, Offset, 1, &gAllOne);
  }

  return EFI_SUCCESS;
}

EFI_STATUS
InitializePpb (
  IN PCI_IO_DEVICE *PciIoDevice
  )
/*++

Routine Description:

Arguments:

Returns:

  None

--*/
// TODO:    PciIoDevice - add argument and description to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  EFI_PCI_IO_PROTOCOL *PciIo;

  PciIo = &(PciIoDevice->PciIo);

  //
  // Put all the resource apertures including IO16
  // Io32, pMem32, pMem64 to quiescent state
  // Resource base all ones, Resource limit all zeros
  //
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint8, 0x1C, 1, &gAllOne);
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint8, 0x1D, 1, &gAllZero);

  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint16, 0x20, 1, &gAllOne);
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint16, 0x22, 1, &gAllZero);

  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint16, 0x24, 1, &gAllOne);
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint16, 0x26, 1, &gAllZero);

  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint32, 0x28, 1, &gAllOne);
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint32, 0x2C, 1, &gAllZero);

  //
  // don't support use io32 as for now
  //
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint16, 0x30, 1, &gAllOne);
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint16, 0x32, 1, &gAllZero);

  //
  // Force Interrupt line to zero for cards that come up randomly
  //
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint8, 0x3C, 1, &gAllZero);

  return EFI_SUCCESS;
}

EFI_STATUS
InitializeP2C (
  IN PCI_IO_DEVICE *PciIoDevice
  )
/*++

Routine Description:

Arguments:

Returns:

  None

--*/
// TODO:    PciIoDevice - add argument and description to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  EFI_PCI_IO_PROTOCOL *PciIo;

  PciIo = &(PciIoDevice->PciIo);

  //
  // Put all the resource apertures including IO16
  // Io32, pMem32, pMem64 to quiescent state(
  // Resource base all ones, Resource limit all zeros
  //
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint32, 0x1c, 1, &gAllOne);
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint32, 0x20, 1, &gAllZero);

  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint32, 0x24, 1, &gAllOne);
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint32, 0x28, 1, &gAllZero);

  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint32, 0x2c, 1, &gAllOne);
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint32, 0x30, 1, &gAllZero);

  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint32, 0x34, 1, &gAllOne);
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint32, 0x38, 1, &gAllZero);

  //
  // Force Interrupt line to zero for cards that come up randomly
  //
  PciIo->Pci.Write (PciIo, EfiPciIoWidthUint8, 0x3C, 1, &gAllZero);
  return EFI_SUCCESS;
}

PCI_IO_DEVICE *
CreatePciIoDevice (
  IN EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL  *PciRootBridgeIo,
  IN PCI_TYPE00                       *Pci,
  UINT8                               Bus,
  UINT8                               Device,
  UINT8                               Func
  )
/*++

Routine Description:

Arguments:

Returns:

  None

--*/
// TODO:    PciRootBridgeIo - add argument and description to function comment
// TODO:    Pci - add argument and description to function comment
// TODO:    Bus - add argument and description to function comment
// TODO:    Device - add argument and description to function comment
// TODO:    Func - add argument and description to function comment
{

  EFI_STATUS    Status;
  PCI_IO_DEVICE *PciIoDevice;

  PciIoDevice = NULL;

  Status = gBS->AllocatePool (
                  EfiBootServicesData,
                  sizeof (PCI_IO_DEVICE),
                  (VOID **) &PciIoDevice
                  );

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

  ZeroMem (PciIoDevice, sizeof (PCI_IO_DEVICE));

  PciIoDevice->Signature        = PCI_IO_DEVICE_SIGNATURE;
  PciIoDevice->Handle           = NULL;
  PciIoDevice->PciRootBridgeIo  = PciRootBridgeIo;
  PciIoDevice->DevicePath       = NULL;
  PciIoDevice->BusNumber        = Bus;
  PciIoDevice->DeviceNumber     = Device;
  PciIoDevice->FunctionNumber   = Func;
  PciIoDevice->Decodes          = 0;
  if (gFullEnumeration) {
    PciIoDevice->Allocated = FALSE;
  } else {
    PciIoDevice->Allocated = TRUE;
  }

  PciIoDevice->Registered         = FALSE;
  PciIoDevice->Attributes         = 0;
  PciIoDevice->Supports           = 0;
  PciIoDevice->BusOverride        = FALSE;
  PciIoDevice->AllOpRomProcessed  = FALSE;

  PciIoDevice->IsPciExp           = FALSE;

  CopyMem (&(PciIoDevice->Pci), Pci, sizeof (PCI_TYPE01));

  //
  // Initialize the PCI I/O instance structure
  //

  Status  = InitializePciIoInstance (PciIoDevice);
  Status  = InitializePciDriverOverrideInstance (PciIoDevice);

  if (EFI_ERROR (Status)) {
    gBS->FreePool (PciIoDevice);
    return NULL;
  }

  //
  // Initialize the reserved resource list
  //
  InitializeListHead (&PciIoDevice->ReservedResourceList);

  //
  // Initialize the driver list
  //
  InitializeListHead (&PciIoDevice->OptionRomDriverList);

  //
  // Initialize the child list
  //
  InitializeListHead (&PciIoDevice->ChildList);

  return PciIoDevice;
}

EFI_STATUS
PciEnumeratorLight (
  IN EFI_HANDLE                    Controller
  )
/*++

Routine Description:

  This routine is used to enumerate entire pci bus system 
  in a given platform

Arguments:

Returns:

  None

--*/
// TODO:    Controller - add argument and description to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{

  EFI_STATUS                        Status;
  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL   *PciRootBridgeIo;
  PCI_IO_DEVICE                     *RootBridgeDev;
  UINT16                            MinBus;
  UINT16                            MaxBus;
  EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *Descriptors;

  MinBus      = 0;
  MaxBus      = PCI_MAX_BUS;
  Descriptors = NULL;

  //
  // If this host bridge has been already enumerated, then return successfully
  //
  if (RootBridgeExisted (Controller)) {
    return EFI_SUCCESS;
  }

  //
  // Open pci root bridge io protocol
  //
  Status = gBS->OpenProtocol (
                  Controller,
                  &gEfiPciRootBridgeIoProtocolGuid,
                  (VOID **) &PciRootBridgeIo,
                  gPciBusDriverBinding.DriverBindingHandle,
                  Controller,
                  EFI_OPEN_PROTOCOL_BY_DRIVER
                  );
  if (EFI_ERROR (Status) && Status != EFI_ALREADY_STARTED) {
    return Status;
  }

  Status = PciRootBridgeIo->Configuration (PciRootBridgeIo, (VOID **) &Descriptors);

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

  while (PciGetBusRange (&Descriptors, &MinBus, &MaxBus, NULL) == EFI_SUCCESS) {

    //
    // Create a device node for root bridge device with a NULL host bridge controller handle
    //
    RootBridgeDev = CreateRootBridge (Controller);

    if (!RootBridgeDev) {
      Descriptors++;
      continue;
    }
    
    //
    // Record the root bridge io protocol
    //
    RootBridgeDev->PciRootBridgeIo = PciRootBridgeIo;

    Status = PciPciDeviceInfoCollector (
              RootBridgeDev,
              (UINT8) MinBus
              );

    if (!EFI_ERROR (Status)) {
      
      //
      // Remove those PCI devices which are rejected when full enumeration
      //
      RemoveRejectedPciDevices (RootBridgeDev->Handle, RootBridgeDev);

      //
      // Process option rom light
      //
      ProcessOptionRomLight (RootBridgeDev);

      //
      // Determine attributes for all devices under this root bridge
      //
      DetermineDeviceAttribute (RootBridgeDev);

      //
      // If successfully, insert the node into device pool
      //
      InsertRootBridge (RootBridgeDev);
    } else {

      //
      // If unsuccessly, destroy the entire node
      //
      DestroyRootBridge (RootBridgeDev);
    }

    Descriptors++;
  }

  return EFI_SUCCESS;
}

EFI_STATUS
PciGetBusRange (
  IN     EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR  **Descriptors,
  OUT    UINT16                             *MinBus,
  OUT    UINT16                             *MaxBus,
  OUT    UINT16                             *BusRange
  )
/*++

Routine Description:

  Get the bus range.

Arguments:

  Descriptors     - A pointer to the address space descriptor.
  MinBus          - The min bus.
  MaxBus          - The max bus.
  BusRange        - The bus range.
  
Returns:
  
  Status Code.

--*/
// TODO:    EFI_SUCCESS - add return value to function comment
// TODO:    EFI_NOT_FOUND - add return value to function comment
{

  while ((*Descriptors)->Desc != ACPI_END_TAG_DESCRIPTOR) {
    if ((*Descriptors)->ResType == ACPI_ADDRESS_SPACE_TYPE_BUS) {
      if (MinBus != NULL) {
        *MinBus = (UINT16) (*Descriptors)->AddrRangeMin;
      }

      if (MaxBus != NULL) {
        *MaxBus = (UINT16) (*Descriptors)->AddrRangeMax;
      }

      if (BusRange != NULL) {
        *BusRange = (UINT16) (*Descriptors)->AddrLen;
      }

      return EFI_SUCCESS;
    }

    (*Descriptors)++;
  }

  return EFI_NOT_FOUND;
}

EFI_STATUS
StartManagingRootBridge (
  IN PCI_IO_DEVICE *RootBridgeDev
  )
/*++

Routine Description:


Arguments:

Returns:

  None

--*/
// TODO:    RootBridgeDev - add argument and description to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  EFI_HANDLE                      RootBridgeHandle;
  EFI_STATUS                      Status;
  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL *PciRootBridgeIo;

  //
  // Get the root bridge handle
  //
  RootBridgeHandle  = RootBridgeDev->Handle;
  PciRootBridgeIo   = NULL;

  //
  // Get the pci root bridge io protocol
  //
  Status = gBS->OpenProtocol (
                  RootBridgeHandle,
                  &gEfiPciRootBridgeIoProtocolGuid,
                  (VOID **) &PciRootBridgeIo,
                  gPciBusDriverBinding.DriverBindingHandle,
                  RootBridgeHandle,
                  EFI_OPEN_PROTOCOL_BY_DRIVER
                  );

  if (EFI_ERROR (Status) && Status != EFI_ALREADY_STARTED) {
    return Status;
  }

  //
  // Store the PciRootBridgeIo protocol into root bridge private data
  //
  RootBridgeDev->PciRootBridgeIo = PciRootBridgeIo;

  return EFI_SUCCESS;

}

BOOLEAN
IsPciDeviceRejected (
  IN PCI_IO_DEVICE *PciIoDevice
  )
/*++

Routine Description:

  This routine can be used to check whether a PCI device should be rejected when light enumeration

Arguments:

Returns:

  TRUE      This device should be rejected
  FALSE     This device shouldn't be rejected

--*/
// TODO:    PciIoDevice - add argument and description to function comment
{
  EFI_STATUS  Status;
  UINT32      TestValue;
  UINT32      OldValue;
  UINT32      Mask;
  UINT8       BarOffset;

  //
  // PPB should be skip!
  //
  if (IS_PCI_BRIDGE (&PciIoDevice->Pci)) {
    return FALSE;
  }

  if (IS_CARDBUS_BRIDGE (&PciIoDevice->Pci)) {
    //
    // Only test base registers for P2C
    //
    for (BarOffset = 0x1C; BarOffset <= 0x38; BarOffset += 2 * sizeof (UINT32)) {

      Mask    = (BarOffset < 0x2C) ? 0xFFFFF000 : 0xFFFFFFFC;
      Status  = BarExisted (PciIoDevice, BarOffset, &TestValue, &OldValue);
      if (EFI_ERROR (Status)) {
        continue;
      }

      TestValue = TestValue & Mask;
      if ((TestValue != 0) && (TestValue == (OldValue & Mask))) {
        //
        // The bar isn't programed, so it should be rejected
        //
        return TRUE;
      }
    }

    return FALSE;
  }

  for (BarOffset = 0x14; BarOffset <= 0x24; BarOffset += sizeof (UINT32)) {
    //
    // Test PCI devices
    //
    Status = BarExisted (PciIoDevice, BarOffset, &TestValue, &OldValue);
    if (EFI_ERROR (Status)) {
      continue;
    }

    if (TestValue & 0x01) {
      
      //
      // IO Bar
      //
      
      Mask      = 0xFFFFFFFC;
      TestValue = TestValue & Mask;
      if ((TestValue != 0) && (TestValue == (OldValue & Mask))) {
        return TRUE;
      }

    } else {
      
      //
      // Mem Bar
      //
      
      Mask      = 0xFFFFFFF0;
      TestValue = TestValue & Mask;

      if ((TestValue & 0x07) == 0x04) {
        
        //
        // Mem64 or PMem64
        //
        BarOffset += sizeof (UINT32);
        if ((TestValue != 0) && (TestValue == (OldValue & Mask))) {
          
          //
          // Test its high 32-Bit BAR
          //
          
          Status = BarExisted (PciIoDevice, BarOffset, &TestValue, &OldValue);
          if (TestValue == OldValue) {
            return TRUE;
          }
        }

      } else {
        
        //
        // Mem32 or PMem32
        //
        if ((TestValue != 0) && (TestValue == (OldValue & Mask))) {
          return TRUE;
        }
      }
    }
  }

  return FALSE;
}

EFI_STATUS
ResetAllPpbBusReg (
  IN PCI_IO_DEVICE                      *Bridge,
  IN UINT8                              StartBusNumber
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  Bridge          - TODO: add argument description
  StartBusNumber  - TODO: add argument description

Returns:

  EFI_SUCCESS - TODO: Add description for return value

--*/
{
  EFI_STATUS                      Status;
  PCI_TYPE00                      Pci;
  UINT8                           Device;
  UINT32                          Register;  
  UINT8                           Func;
  UINT64                          Address;
  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL *PciRootBridgeIo;

  PciRootBridgeIo = Bridge->PciRootBridgeIo;

  for (Device = 0; Device <= PCI_MAX_DEVICE; Device++) {
    for (Func = 0; Func <= PCI_MAX_FUNC; Func++) {

      //
      // Check to see whether a pci device is present
      //
      Status = PciDevicePresent (
                PciRootBridgeIo,
                &Pci,
                StartBusNumber,
                Device,
                Func
                );

      if (!EFI_ERROR (Status) && (IS_PCI_BRIDGE (&Pci))) {
        Register  = 0;
        Address   = EFI_PCI_ADDRESS (StartBusNumber, Device, Func, 0x18);
        Status   = PciRootBridgeIo->Pci.Read (
                                        PciRootBridgeIo,
                                        EfiPciWidthUint32, 
                                        Address,
                                        1,
                                        &Register
                                        );
        //
        // Reset register 18h, 19h, 1Ah on PCI Bridge
        //
        Register &= 0xFF000000;
        Status = PciRootBridgeIo->Pci.Write (
                                        PciRootBridgeIo,
                                        EfiPciWidthUint32, 
                                        Address,
                                        1,
                                        &Register
                                        );
      }

      if (Func == 0 && !IS_PCI_MULTI_FUNC (&Pci)) {
        //
        // Skip sub functions, this is not a multi function device
        //
        Func = PCI_MAX_FUNC;
      }
    }
  }

  return EFI_SUCCESS;
}