/** @file

  Internal generic functions to support fault tolerant write.

Copyright (c) 2006 - 2008, Intel Corporation                                                         
All rights reserved. This program and the accompanying materials                          
are licensed and made available under the terms and conditions of the BSD License         
which accompanies this distribution.  The full text of the license may be found at        
http://opensource.org/licenses/bsd-license.php                                            
                                                                                          
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 

**/

#include <FtwLite.h>

BOOLEAN
IsErasedFlashBuffer (
  IN BOOLEAN         Polarity,
  IN UINT8           *Buffer,
  IN UINTN           BufferSize
  )
/*++

Routine Description:

  Check whether a flash buffer is erased.

Arguments:

  Polarity    - All 1 or all 0
  Buffer      - Buffer to check
  BufferSize  - Size of the buffer

Returns:

  Erased or not.

--*/
{
  UINT8 ErasedValue;
  UINT8 *Ptr;

  if (Polarity) {
    ErasedValue = 0xFF;
  } else {
    ErasedValue = 0;
  }

  Ptr = Buffer;
  while (BufferSize--) {
    if (*Ptr++ != ErasedValue) {
      return FALSE;
    }
  }

  return TRUE;
}

EFI_STATUS
FtwEraseBlock (
  IN EFI_FTW_LITE_DEVICE              *FtwLiteDevice,
  EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *FvBlock,
  EFI_LBA                             Lba
  )
/*++

Routine Description:
    To Erase one block. The size is FTW_BLOCK_SIZE

Arguments:
    FtwLiteDevice - Calling context
    FvBlock       - FVB Protocol interface
    Lba        - Lba of the firmware block

Returns:
    EFI_SUCCESS   - Block LBA is Erased successfully
    Others        - Error occurs

--*/
{
  return FvBlock->EraseBlocks (
                    FvBlock,
                    Lba,
                    FtwLiteDevice->NumberOfSpareBlock,
                    EFI_LBA_LIST_TERMINATOR
                    );
}

EFI_STATUS
FtwEraseSpareBlock (
  IN EFI_FTW_LITE_DEVICE   *FtwLiteDevice
  )
/*++

Routine Description:

  Erase spare block.

Arguments:

  FtwLiteDevice - Calling context

Returns:

  Status code

--*/
{
  return FtwLiteDevice->FtwBackupFvb->EraseBlocks (
                                        FtwLiteDevice->FtwBackupFvb,
                                        FtwLiteDevice->FtwSpareLba,
                                        FtwLiteDevice->NumberOfSpareBlock,
                                        EFI_LBA_LIST_TERMINATOR
                                        );
}

EFI_STATUS
FtwGetFvbByHandle (
  IN EFI_HANDLE                           FvBlockHandle,
  OUT EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  **FvBlock
  )
/*++

Routine Description:
    Retrive the proper FVB protocol interface by HANDLE.

Arguments:
    FvBlockHandle       - The handle of FVB protocol that provides services for 
                          reading, writing, and erasing the target block.
    FvBlock             - The interface of FVB protocol

Returns:
    EFI_SUCCESS         - The function completed successfully
    EFI_ABORTED         - The function could not complete successfully
--*/
{
  //
  // To get the FVB protocol interface on the handle
  //
  return gBS->HandleProtocol (
                FvBlockHandle,
                &gEfiFirmwareVolumeBlockProtocolGuid,
                (VOID **) FvBlock
                );
}

EFI_STATUS
GetFvbByAddress (
  IN  EFI_PHYSICAL_ADDRESS               Address,
  OUT EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL **FvBlock
  )
/*++

Routine Description:

  Get firmware block by address.

Arguments:

  Address - Address specified the block
  FvBlock - The block caller wanted

Returns:

  Status code

  EFI_NOT_FOUND - Block not found

--*/
{
  EFI_STATUS                          Status;
  EFI_HANDLE                          *HandleBuffer;
  UINTN                               HandleCount;
  UINTN                               Index;
  EFI_PHYSICAL_ADDRESS                FvbBaseAddress;
  EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *Fvb;
  EFI_FIRMWARE_VOLUME_HEADER          *FwVolHeader;

  *FvBlock = NULL;
  //
  // Locate all handles of Fvb protocol
  //
  Status = gBS->LocateHandleBuffer (
                  ByProtocol,
                  &gEfiFirmwareVolumeBlockProtocolGuid,
                  NULL,
                  &HandleCount,
                  &HandleBuffer
                  );
  if (EFI_ERROR (Status)) {
    return EFI_NOT_FOUND;
  }
  //
  // Search all FVB until find the right one
  //
  for (Index = 0; Index < HandleCount; Index += 1) {
    Status = gBS->HandleProtocol (
                    HandleBuffer[Index],
                    &gEfiFirmwareVolumeBlockProtocolGuid,
                    (VOID **) &Fvb
                    );
    if (EFI_ERROR (Status)) {
      Status = EFI_NOT_FOUND;
      break;
    }
    //
    // Compare the address and select the right one
    //
    Status = Fvb->GetPhysicalAddress (Fvb, &FvbBaseAddress);
    if (EFI_ERROR (Status)) {
      continue;
    }

    FwVolHeader = (EFI_FIRMWARE_VOLUME_HEADER *) ((UINTN) FvbBaseAddress);
    if ((Address >= FvbBaseAddress) && (Address <= (FvbBaseAddress + (FwVolHeader->FvLength - 1)))) {
      *FvBlock  = Fvb;
      Status    = EFI_SUCCESS;
      break;
    }
  }

  FreePool (HandleBuffer);
  return Status;
}

BOOLEAN
IsInWorkingBlock (
  EFI_FTW_LITE_DEVICE                 *FtwLiteDevice,
  EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *FvBlock,
  EFI_LBA                             Lba
  )
/*++

Routine Description:

  Is it in working block?

Arguments:

  FtwLiteDevice - Calling context
  FvBlock       - Fvb protocol instance
  Lba           - The block specified

Returns:

  In working block or not

--*/
{
  //
  // If matching the following condition, the target block is in working block.
  // 1. Target block is on the FV of working block (Using the same FVB protocol instance).
  // 2. Lba falls into the range of working block.
  //
  return (BOOLEAN)
    (
      (FvBlock == FtwLiteDevice->FtwFvBlock) &&
      (Lba >= FtwLiteDevice->FtwWorkBlockLba) &&
      (Lba <= FtwLiteDevice->FtwWorkSpaceLba)
    );
}

EFI_STATUS
FlushSpareBlockToTargetBlock (
  EFI_FTW_LITE_DEVICE                 *FtwLiteDevice,
  EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *FvBlock,
  EFI_LBA                             Lba
  )
/*++

Routine Description:
    Copy the content of spare block to a target block. Size is FTW_BLOCK_SIZE.
    Spare block is accessed by FTW backup FVB protocol interface. LBA is 
    FtwLiteDevice->FtwSpareLba.
    Target block is accessed by FvBlock protocol interface. LBA is Lba.

Arguments:
    FtwLiteDevice  - The private data of FTW_LITE driver
    FvBlock        - FVB Protocol interface to access target block
    Lba            - Lba of the target block

Returns:
    EFI_SUCCESS              - Spare block content is copied to target block
    EFI_INVALID_PARAMETER    - Input parameter error
    EFI_OUT_OF_RESOURCES     - Allocate memory error
    EFI_ABORTED              - The function could not complete successfully

--*/
{
  EFI_STATUS  Status;
  UINTN       Length;
  UINT8       *Buffer;
  UINTN       Count;
  UINT8       *Ptr;
  UINTN       Index;

  if ((FtwLiteDevice == NULL) || (FvBlock == NULL)) {
    return EFI_INVALID_PARAMETER;
  }
  //
  // Allocate a memory buffer
  //
  Length  = FtwLiteDevice->SpareAreaLength;
  Buffer  = AllocatePool (Length);
  if (Buffer == NULL) {
    return EFI_OUT_OF_RESOURCES;
  }
  //
  // Read all content of spare block to memory buffer
  //
  Ptr = Buffer;
  for (Index = 0; Index < FtwLiteDevice->NumberOfSpareBlock; Index += 1) {
    Count = FtwLiteDevice->SizeOfSpareBlock;
    Status = FtwLiteDevice->FtwBackupFvb->Read (
                                            FtwLiteDevice->FtwBackupFvb,
                                            FtwLiteDevice->FtwSpareLba + Index,
                                            0,
                                            &Count,
                                            Ptr
                                            );
    if (EFI_ERROR (Status)) {
      FreePool (Buffer);
      return Status;
    }

    Ptr += Count;
  }
  //
  // Erase the target block
  //
  Status = FtwEraseBlock (FtwLiteDevice, FvBlock, Lba);
  if (EFI_ERROR (Status)) {
    FreePool (Buffer);
    return EFI_ABORTED;
  }
  //
  // Write memory buffer to block, using the FvbBlock protocol interface
  //
  Ptr = Buffer;
  for (Index = 0; Index < FtwLiteDevice->NumberOfSpareBlock; Index += 1) {
    Count   = FtwLiteDevice->SizeOfSpareBlock;
    Status  = FvBlock->Write (FvBlock, Lba + Index, 0, &Count, Ptr);
    if (EFI_ERROR (Status)) {
      DEBUG ((EFI_D_FTW_LITE, "FtwLite: FVB Write block - %r\n", Status));
      FreePool (Buffer);
      return Status;
    }

    Ptr += Count;
  }

  FreePool (Buffer);

  return Status;
}

EFI_STATUS
FlushSpareBlockToWorkingBlock (
  EFI_FTW_LITE_DEVICE          *FtwLiteDevice
  )
/*++

Routine Description:
    Copy the content of spare block to working block. Size is FTW_BLOCK_SIZE.
    Spare block is accessed by FTW backup FVB protocol interface. LBA is 
    FtwLiteDevice->FtwSpareLba.
    Working block is accessed by FTW working FVB protocol interface. LBA is 
    FtwLiteDevice->FtwWorkBlockLba.

Arguments:
    FtwLiteDevice  - The private data of FTW_LITE driver

Returns:
    EFI_SUCCESS              - Spare block content is copied to target block
    EFI_OUT_OF_RESOURCES     - Allocate memory error
    EFI_ABORTED              - The function could not complete successfully

Notes:
    Since the working block header is important when FTW initializes, the 
    state of the operation should be handled carefully. The Crc value is 
    calculated without STATE element. 

--*/
{
  EFI_STATUS                              Status;
  UINTN                                   Length;
  UINT8                                   *Buffer;
  EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER *WorkingBlockHeader;
  EFI_LBA                                 WorkSpaceLbaOffset;
  UINTN                                   Count;
  UINT8                                   *Ptr;
  UINTN                                   Index;

  //
  // Allocate a memory buffer
  //
  Length  = FtwLiteDevice->SpareAreaLength;
  Buffer  = AllocatePool (Length);
  if (Buffer == NULL) {
    return EFI_OUT_OF_RESOURCES;
  }
  //
  // To  guarantee that the WorkingBlockValid is set on spare block
  //
  WorkSpaceLbaOffset = FtwLiteDevice->FtwWorkSpaceLba - FtwLiteDevice->FtwWorkBlockLba;
  FtwUpdateFvState (
    FtwLiteDevice->FtwBackupFvb,
    FtwLiteDevice->FtwSpareLba + WorkSpaceLbaOffset,
    FtwLiteDevice->FtwWorkSpaceBase + sizeof (EFI_GUID) + sizeof (UINT32),
    WORKING_BLOCK_VALID
    );
  //
  // Read from spare block to memory buffer
  //
  Ptr = Buffer;
  for (Index = 0; Index < FtwLiteDevice->NumberOfSpareBlock; Index += 1) {
    Count = FtwLiteDevice->SizeOfSpareBlock;
    Status = FtwLiteDevice->FtwBackupFvb->Read (
                                            FtwLiteDevice->FtwBackupFvb,
                                            FtwLiteDevice->FtwSpareLba + Index,
                                            0,
                                            &Count,
                                            Ptr
                                            );
    if (EFI_ERROR (Status)) {
      FreePool (Buffer);
      return Status;
    }

    Ptr += Count;
  }
  //
  // Clear the CRC and STATE, copy data from spare to working block.
  //
  WorkingBlockHeader = (EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER *) (Buffer + (UINTN) WorkSpaceLbaOffset * FtwLiteDevice->SizeOfSpareBlock + FtwLiteDevice->FtwWorkSpaceBase);
  InitWorkSpaceHeader (WorkingBlockHeader);
  WorkingBlockHeader->WorkingBlockValid   = FTW_ERASE_POLARITY;
  WorkingBlockHeader->WorkingBlockInvalid = FTW_ERASE_POLARITY;

  //
  // target block is working block, then
  //   Set WorkingBlockInvalid in EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER
  //   before erase the working block.
  //
  //  Offset = EFI_FIELD_OFFSET(EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER,
  //                            WorkingBlockInvalid);
  // To skip Signature and Crc: sizeof(EFI_GUID)+sizeof(UINT32).
  //
  Status = FtwUpdateFvState (
            FtwLiteDevice->FtwFvBlock,
            FtwLiteDevice->FtwWorkSpaceLba,
            FtwLiteDevice->FtwWorkSpaceBase + sizeof (EFI_GUID) + sizeof (UINT32),
            WORKING_BLOCK_INVALID
            );
  if (EFI_ERROR (Status)) {
    FreePool (Buffer);
    return EFI_ABORTED;
  }

  FtwLiteDevice->FtwWorkSpaceHeader->WorkingBlockInvalid = FTW_VALID_STATE;

  //
  // Erase the working block
  //
  Status = FtwEraseBlock (
            FtwLiteDevice,
            FtwLiteDevice->FtwFvBlock,
            FtwLiteDevice->FtwWorkBlockLba
            );
  if (EFI_ERROR (Status)) {
    FreePool (Buffer);
    return EFI_ABORTED;
  }
  //
  // Write memory buffer to working block, using the FvbBlock protocol interface
  //
  Ptr = Buffer;
  for (Index = 0; Index < FtwLiteDevice->NumberOfSpareBlock; Index += 1) {
    Count = FtwLiteDevice->SizeOfSpareBlock;
    Status = FtwLiteDevice->FtwFvBlock->Write (
                                          FtwLiteDevice->FtwFvBlock,
                                          FtwLiteDevice->FtwWorkBlockLba + Index,
                                          0,
                                          &Count,
                                          Ptr
                                          );
    if (EFI_ERROR (Status)) {
      DEBUG ((EFI_D_FTW_LITE, "FtwLite: FVB Write block - %r\n", Status));
      FreePool (Buffer);
      return Status;
    }

    Ptr += Count;
  }
  //
  // Since the memory buffer will not be used, free memory Buffer.
  //
  FreePool (Buffer);

  //
  // Update the VALID of the working block
  //
  // Offset = EFI_FIELD_OFFSET(EFI_FAULT_TOLERANT_WORKING_BLOCK_HEADER,
  //                           WorkingBlockValid);
  // Hardcode offset sizeof(EFI_GUID)+sizeof(UINT32), to skip Signature and Crc
  //
  Status = FtwUpdateFvState (
            FtwLiteDevice->FtwFvBlock,
            FtwLiteDevice->FtwWorkSpaceLba,
            FtwLiteDevice->FtwWorkSpaceBase + sizeof (EFI_GUID) + sizeof (UINT32),
            WORKING_BLOCK_VALID
            );
  if (EFI_ERROR (Status)) {
    return EFI_ABORTED;
  }

  FtwLiteDevice->FtwWorkSpaceHeader->WorkingBlockValid = FTW_VALID_STATE;

  return EFI_SUCCESS;
}