[mirror_edk2.git] / MdeModulePkg / Universal / FirmwareVolume / FaultTolerantWriteDxe / Ia32 / Ia32FtwMisc.c

/** @file\r
  \r
  Ia32 platform related code to support FtwLite.\r
  \r
Copyright (c) 2006 - 2008, Intel Corporation                                                         \r
All rights reserved. This program and the accompanying materials                          \r
are licensed and made available under the terms and conditions of the BSD License         \r
which accompanies this distribution.  The full text of the license may be found at        \r
http://opensource.org/licenses/bsd-license.php                                            \r
                                                                                          \r
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     \r
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. \r
\r
**/\r
\r
\r
#include "FtwLite.h"\r
\r
//\r
// MACROs for boot block update\r
//\r
#define BOOT_BLOCK_BASE 0xFFFF0000\r
\r
//\r
// (LPC -- D31:F0)\r
//\r
#define LPC_BUS_NUMBER    0x00\r
#define LPC_DEVICE_NUMBER 0x1F\r
#define LPC_IF            0xF0\r
//\r
// Top swap\r
//\r
#define GEN_STATUS    0xD4\r
#define TOP_SWAP_BIT  (1 << 13)\r
\r
/**\r
\r
  Read PCI register value.\r
  This is a internal function.\r
\r
\r
  @param Offset          Offset of the register\r
\r
  @return The pci register value.\r
\r
**/\r
UINT32\r
ReadPciRegister (\r
  IN UINT32                 Offset\r
  )\r
{\r
  EFI_STATUS                      Status;\r
  UINT32                          Value;\r
  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL *PciRootBridgeIo;\r
\r
  Value   = 0;\r
  Status  = gBS->LocateProtocol (&gEfiPciRootBridgeIoProtocolGuid, NULL, (VOID **) &PciRootBridgeIo);\r
  if (EFI_ERROR (Status)) {\r
    DEBUG ((EFI_D_ERROR, "FtwLite: Locate PCI root bridge io protocol - %r", Status));\r
    return 0;\r
  }\r
\r
  Status = PciRootBridgeIo->Pci.Read (\r
                                  PciRootBridgeIo,\r
                                  EfiPciWidthUint32,\r
                                  EFI_PCI_ADDRESS (\r
                                    LPC_BUS_NUMBER,\r
                                    LPC_DEVICE_NUMBER,\r
                                    LPC_IF,\r
                                    Offset\r
                                    ),\r
                                  1,\r
                                  &Value\r
                                  );\r
  ASSERT_EFI_ERROR (Status);\r
\r
  return Value;\r
}\r
\r
/**\r
\r
  Get swap state\r
\r
  This is a internal function.\r
\r
  @param FtwLiteDevice   Calling context\r
  @param SwapState       Swap state\r
\r
  @retval  EFI_SUCCESS  State successfully got\r
\r
**/\r
EFI_STATUS\r
GetSwapState (\r
  IN EFI_FTW_LITE_DEVICE    *FtwLiteDevice,\r
  OUT BOOLEAN               *SwapState\r
  )\r
{\r
  //\r
  // Top swap status is 13 bit\r
  //\r
  *SwapState = (BOOLEAN) ((ReadPciRegister (GEN_STATUS) & TOP_SWAP_BIT) != 0);\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Set swap state.\r
\r
  This is a internal function.\r
\r
  @param FtwLiteDevice   Indicates a pointer to the calling context.\r
  @param TopSwap         New swap state\r
\r
  @retval  EFI_SUCCESS    The function completed successfully\r
                          Note:\r
                          the Top-Swap bit (bit 13, D31: F0, Offset D4h). Note that\r
                          software will not be able to clear the Top-Swap bit until the system is\r
                          rebooted without GNT[A]# being pulled down.\r
\r
**/\r
EFI_STATUS\r
SetSwapState (\r
  IN EFI_FTW_LITE_DEVICE    *FtwLiteDevice,\r
  IN  BOOLEAN               TopSwap\r
  )\r
{\r
  UINT32                          GenStatus;\r
  EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL *PciRootBridgeIo;\r
  EFI_STATUS                      Status;\r
\r
  //\r
  // Top-Swap bit (bit 13, D31: F0, Offset D4h)\r
  //\r
  GenStatus = ReadPciRegister (GEN_STATUS);\r
\r
  //\r
  // Set 13 bit, according to input NewSwapState\r
  //\r
  if (TopSwap) {\r
    GenStatus |= TOP_SWAP_BIT;\r
  } else {\r
    GenStatus &= ~TOP_SWAP_BIT;\r
  }\r
\r
  Status = gBS->LocateProtocol (&gEfiPciRootBridgeIoProtocolGuid, NULL, (VOID **) &PciRootBridgeIo);\r
  if (EFI_ERROR (Status)) {\r
    DEBUG ((EFI_D_ERROR, "FtwLite: Locate PCI root bridge io protocol - %r", Status));\r
    return Status;\r
  }\r
  //\r
  // Write back the GenStatus register\r
  //\r
  Status = PciRootBridgeIo->Pci.Write (\r
                                  PciRootBridgeIo,\r
                                  EfiPciWidthUint32,\r
                                  EFI_PCI_ADDRESS (\r
                                    LPC_BUS_NUMBER,\r
                                    LPC_DEVICE_NUMBER,\r
                                    LPC_IF,\r
                                    GEN_STATUS\r
                                    ),\r
                                  1,\r
                                  &GenStatus\r
                                  );\r
\r
  DEBUG_CODE_BEGIN ();\r
    if (TopSwap) {\r
      DEBUG ((EFI_D_ERROR, "SAR: Set top swap\n"));\r
    } else {\r
      DEBUG ((EFI_D_ERROR, "SAR: Clear top swap\n"));\r
    }\r
  DEBUG_CODE_END ();\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
\r
  Check whether the block is a boot block.\r
\r
\r
  @param FtwLiteDevice   Calling context\r
  @param FvBlock         Fvb protocol instance\r
  @param Lba             Lba value\r
\r
  @retval FALSE           This is a boot block.\r
  @retval TRUE            This is not a boot block.\r
\r
**/\r
BOOLEAN\r
IsBootBlock (\r
  EFI_FTW_LITE_DEVICE                 *FtwLiteDevice,\r
  EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *FvBlock,\r
  EFI_LBA                             Lba\r
  )\r
{\r
  EFI_STATUS                          Status;\r
  EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *BootFvb;\r
\r
  Status = GetFvbByAddress (BOOT_BLOCK_BASE, &BootFvb);\r
  if (EFI_ERROR (Status)) {\r
    return FALSE;\r
  }\r
  //\r
  // Compare the Fvb\r
  //\r
  return (BOOLEAN) (FvBlock == BootFvb);\r
}\r
\r
/**\r
  Copy the content of spare block to a boot block. Size is FTW_BLOCK_SIZE.\r
  Spare block is accessed by FTW backup FVB protocol interface. LBA is\r
  FtwLiteDevice->FtwSpareLba.\r
  Boot block is accessed by BootFvb protocol interface. LBA is 0.\r
\r
\r
  @param FtwLiteDevice   The private data of FTW_LITE driver\r
\r
  @retval  EFI_SUCCESS               Spare block content is copied to boot block\r
  @retval  EFI_INVALID_PARAMETER     Input parameter error\r
  @retval  EFI_OUT_OF_RESOURCES      Allocate memory error\r
  @retval  EFI_ABORTED               The function could not complete successfully\r
                                     Notes:\r
                                     FTW will do extra work on boot block update.\r
                                     FTW should depend on a protocol of EFI_ADDRESS_RANGE_SWAP_PROTOCOL,\r
                                     which is produced by a chipset driver.\r
                                     FTW updating boot block steps:\r
                                     1. Erase top swap block (0xFFFE-0xFFFEFFFF) and write data to it ready\r
                                     2. Read data from top swap block to memory buffer\r
                                     3. SetSwapState(EFI_SWAPPED)\r
                                     4. Erasing boot block (0xFFFF-0xFFFFFFFF)\r
                                     5. Programming boot block until the boot block is ok.\r
                                     6. SetSwapState(UNSWAPPED)\r
                                     Notes:\r
                                     1. Since the SwapState bit is saved in CMOS, FTW can restore and continue\r
                                     even in the scenario of power failure.\r
                                     2. FTW shall not allow to update boot block when battery state is error.\r
\r
**/\r
EFI_STATUS\r
FlushSpareBlockToBootBlock (\r
  EFI_FTW_LITE_DEVICE      *FtwLiteDevice\r
  )\r
{\r
  EFI_STATUS                          Status;\r
  UINTN                               Length;\r
  UINT8                               *Buffer;\r
  UINTN                               Count;\r
  UINT8                               *Ptr;\r
  UINTN                               Index;\r
  BOOLEAN                             TopSwap;\r
  EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL  *BootFvb;\r
  EFI_LBA                             BootLba;\r
\r
  //\r
  // Allocate a memory buffer\r
  //\r
  Length  = FtwLiteDevice->SpareAreaLength;\r
  Buffer  = AllocatePool (Length);\r
  if (Buffer == NULL) {\r
    return EFI_OUT_OF_RESOURCES;\r
  }\r
  //\r
  // Get TopSwap bit state\r
  //\r
  Status = GetSwapState (FtwLiteDevice, &TopSwap);\r
  if (EFI_ERROR (Status)) {\r
    DEBUG ((EFI_D_ERROR, "FtwLite: Get Top Swapped status - %r\n", Status));\r
    FreePool (Buffer);\r
    return EFI_ABORTED;\r
  }\r
\r
  if (TopSwap) {\r
    //\r
    // Get FVB of current boot block\r
    //\r
    Status = GetFvbByAddress (FtwLiteDevice->SpareAreaAddress + FTW_BLOCK_SIZE, &BootFvb);\r
    if (EFI_ERROR (Status)) {\r
      FreePool (Buffer);\r
      return Status;\r
    }\r
    //\r
    // Read data from current boot block\r
    //\r
    BootLba = 0;\r
    Ptr     = Buffer;\r
    for (Index = 0; Index < FtwLiteDevice->NumberOfSpareBlock; Index += 1) {\r
      Count = FtwLiteDevice->SizeOfSpareBlock;\r
      Status = BootFvb->Read (\r
                          BootFvb,\r
                          BootLba + Index,\r
                          0,\r
                          &Count,\r
                          Ptr\r
                          );\r
      if (EFI_ERROR (Status)) {\r
        FreePool (Buffer);\r
        return Status;\r
      }\r
\r
      Ptr += Count;\r
    }\r
\r
  } else {\r
    //\r
    // Read data from spare block\r
    //\r
    Ptr = Buffer;\r
    for (Index = 0; Index < FtwLiteDevice->NumberOfSpareBlock; Index += 1) {\r
      Count = FtwLiteDevice->SizeOfSpareBlock;\r
      Status = FtwLiteDevice->FtwBackupFvb->Read (\r
                                              FtwLiteDevice->FtwBackupFvb,\r
                                              FtwLiteDevice->FtwSpareLba + Index,\r
                                              0,\r
                                              &Count,\r
                                              Ptr\r
                                              );\r
      if (EFI_ERROR (Status)) {\r
        FreePool (Buffer);\r
        return Status;\r
      }\r
\r
      Ptr += Count;\r
    }\r
    //\r
    // Set TopSwap bit\r
    //\r
    Status = SetSwapState (FtwLiteDevice, TRUE);\r
    DEBUG ((EFI_D_ERROR, "FtwLite: Set Swap State - %r\n", Status));\r
    ASSERT_EFI_ERROR (Status);\r
  }\r
  //\r
  // Erase boot block. After setting TopSwap bit, it's spare block now!\r
  //\r
  Status = FtwEraseSpareBlock (FtwLiteDevice);\r
  if (EFI_ERROR (Status)) {\r
    FreePool (Buffer);\r
    return EFI_ABORTED;\r
  }\r
  //\r
  // Write memory buffer to currenet spare block\r
  //\r
  Ptr = Buffer;\r
  for (Index = 0; Index < FtwLiteDevice->NumberOfSpareBlock; Index += 1) {\r
    Count = FtwLiteDevice->SizeOfSpareBlock;\r
    Status = FtwLiteDevice->FtwBackupFvb->Write (\r
                                            FtwLiteDevice->FtwBackupFvb,\r
                                            FtwLiteDevice->FtwSpareLba + Index,\r
                                            0,\r
                                            &Count,\r
                                            Ptr\r
                                            );\r
    if (EFI_ERROR (Status)) {\r
      DEBUG ((EFI_D_FTW_LITE, "FtwLite: FVB Write boot block - %r\n", Status));\r
      FreePool (Buffer);\r
      return Status;\r
    }\r
\r
    Ptr += Count;\r
  }\r
\r
  FreePool (Buffer);\r
\r
  //\r
  // Clear TopSwap bit\r
  //\r
  Status = SetSwapState (FtwLiteDevice, FALSE);\r
  DEBUG ((EFI_D_ERROR, "FtwLite: Clear Swap State - %r\n", Status));\r
  ASSERT_EFI_ERROR (Status);\r
\r
  return EFI_SUCCESS;\r
}\r
Commit	Line	Data
6cc9ca32 LG	1	/** @file\r
	2	\r
	3	Ia32 platform related code to support FtwLite.\r
	4	\r
	5	Copyright (c) 2006 - 2008, Intel Corporation \r
d7dec593	6	All rights reserved. This program and the accompanying materials \r
	7	are licensed and made available under the terms and conditions of the BSD License \r
	8	which accompanies this distribution. The full text of the license may be found at \r
	9	http://opensource.org/licenses/bsd-license.php \r
	10	\r
	11	THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, \r
	12	WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. \r
	13	\r
6cc9ca32	14	**/\r
d7dec593	15	\r
d7dec593	16	\r
e87a334f	17	#include "FtwLite.h"\r
d7dec593	18	\r
	19	//\r
	20	// MACROs for boot block update\r
	21	//\r
	22	#define BOOT_BLOCK_BASE 0xFFFF0000\r
	23	\r
	24	//\r
	25	// (LPC -- D31:F0)\r
	26	//\r
	27	#define LPC_BUS_NUMBER 0x00\r
	28	#define LPC_DEVICE_NUMBER 0x1F\r
	29	#define LPC_IF 0xF0\r
	30	//\r
	31	// Top swap\r
	32	//\r
	33	#define GEN_STATUS 0xD4\r
	34	#define TOP_SWAP_BIT (1 << 13)\r
	35	\r
6aab8214	36	/**\r
d7dec593	37	\r
ca4eb92e	38	Read PCI register value.\r
	39	This is a internal function.\r
	40	\r
	41	\r
	42	@param Offset Offset of the register\r
	43	\r
	44	@return The pci register value.\r
	45	\r
	46	**/\r
	47	UINT32\r
	48	ReadPciRegister (\r
	49	IN UINT32 Offset\r
	50	)\r
	51	{\r
	52	EFI_STATUS Status;\r
	53	UINT32 Value;\r
	54	EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL *PciRootBridgeIo;\r
	55	\r
	56	Value = 0;\r
	57	Status = gBS->LocateProtocol (&gEfiPciRootBridgeIoProtocolGuid, NULL, (VOID **) &PciRootBridgeIo);\r
	58	if (EFI_ERROR (Status)) {\r
	59	DEBUG ((EFI_D_ERROR, "FtwLite: Locate PCI root bridge io protocol - %r", Status));\r
	60	return 0;\r
	61	}\r
	62	\r
	63	Status = PciRootBridgeIo->Pci.Read (\r
	64	PciRootBridgeIo,\r
	65	EfiPciWidthUint32,\r
	66	EFI_PCI_ADDRESS (\r
	67	LPC_BUS_NUMBER,\r
	68	LPC_DEVICE_NUMBER,\r
	69	LPC_IF,\r
	70	Offset\r
	71	),\r
	72	1,\r
	73	&Value\r
	74	);\r
	75	ASSERT_EFI_ERROR (Status);\r
	76	\r
	77	return Value;\r
	78	}\r
	79	\r
	80	/**\r
	81	\r
	82	Get swap state\r
d7dec593	83	\r
6aab8214	84	This is a internal function.\r
d7dec593	85	\r
6aab8214	86	@param FtwLiteDevice Calling context\r
6aab8214	87	@param SwapState Swap state\r
d7dec593	88	\r
6aab8214	89	@retval EFI_SUCCESS State successfully got\r
d7dec593	90	\r
6aab8214	91	**/\r
	92	EFI_STATUS\r
	93	GetSwapState (\r
	94	IN EFI_FTW_LITE_DEVICE *FtwLiteDevice,\r
	95	OUT BOOLEAN *SwapState\r
	96	)\r
d7dec593	97	{\r
	98	//\r
	99	// Top swap status is 13 bit\r
	100	//\r
ca4eb92e	101	*SwapState = (BOOLEAN) ((ReadPciRegister (GEN_STATUS) & TOP_SWAP_BIT) != 0);\r
d7dec593	102	\r
	103	return EFI_SUCCESS;\r
	104	}\r
	105	\r
6aab8214	106	/**\r
	107	Set swap state.\r
	108	\r
	109	This is a internal function.\r
	110	\r
	111	@param FtwLiteDevice Indicates a pointer to the calling context.\r
	112	@param TopSwap New swap state\r
	113	\r
	114	@retval EFI_SUCCESS The function completed successfully\r
	115	Note:\r
	116	the Top-Swap bit (bit 13, D31: F0, Offset D4h). Note that\r
	117	software will not be able to clear the Top-Swap bit until the system is\r
	118	rebooted without GNT[A]# being pulled down.\r
	119	\r
	120	**/\r
d7dec593	121	EFI_STATUS\r
	122	SetSwapState (\r
	123	IN EFI_FTW_LITE_DEVICE *FtwLiteDevice,\r
	124	IN BOOLEAN TopSwap\r
	125	)\r
d7dec593	126	{\r
	127	UINT32 GenStatus;\r
	128	EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL *PciRootBridgeIo;\r
	129	EFI_STATUS Status;\r
	130	\r
	131	//\r
	132	// Top-Swap bit (bit 13, D31: F0, Offset D4h)\r
	133	//\r
ca4eb92e	134	GenStatus = ReadPciRegister (GEN_STATUS);\r
d7dec593	135	\r
	136	//\r
	137	// Set 13 bit, according to input NewSwapState\r
	138	//\r
	139	if (TopSwap) {\r
	140	GenStatus \|= TOP_SWAP_BIT;\r
	141	} else {\r
	142	GenStatus &= ~TOP_SWAP_BIT;\r
	143	}\r
	144	\r
ca4eb92e	145	Status = gBS->LocateProtocol (&gEfiPciRootBridgeIoProtocolGuid, NULL, (VOID **) &PciRootBridgeIo);\r
	146	if (EFI_ERROR (Status)) {\r
	147	DEBUG ((EFI_D_ERROR, "FtwLite: Locate PCI root bridge io protocol - %r", Status));\r
	148	return Status;\r
	149	}\r
d7dec593	150	//\r
	151	// Write back the GenStatus register\r
	152	//\r
ca4eb92e	153	Status = PciRootBridgeIo->Pci.Write (\r
	154	PciRootBridgeIo,\r
	155	EfiPciWidthUint32,\r
	156	EFI_PCI_ADDRESS (\r
	157	LPC_BUS_NUMBER,\r
	158	LPC_DEVICE_NUMBER,\r
	159	LPC_IF,\r
	160	GEN_STATUS\r
	161	),\r
	162	1,\r
	163	&GenStatus\r
	164	);\r
d7dec593	165	\r
	166	DEBUG_CODE_BEGIN ();\r
	167	if (TopSwap) {\r
	168	DEBUG ((EFI_D_ERROR, "SAR: Set top swap\n"));\r
	169	} else {\r
	170	DEBUG ((EFI_D_ERROR, "SAR: Clear top swap\n"));\r
	171	}\r
	172	DEBUG_CODE_END ();\r
	173	\r
	174	return EFI_SUCCESS;\r
	175	}\r
	176	\r
6aab8214	177	/**\r
d7dec593	178	\r
	179	Check whether the block is a boot block.\r
	180	\r
d7dec593	181	\r
6aab8214	182	@param FtwLiteDevice Calling context\r
	183	@param FvBlock Fvb protocol instance\r
	184	@param Lba Lba value\r
d7dec593	185	\r
6aab8214	186	@retval FALSE This is a boot block.\r
6aab8214	187	@retval TRUE This is not a boot block.\r
d7dec593	188	\r
6aab8214	189	**/\r
	190	BOOLEAN\r
	191	IsBootBlock (\r
	192	EFI_FTW_LITE_DEVICE *FtwLiteDevice,\r
	193	EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL *FvBlock,\r
	194	EFI_LBA Lba\r
	195	)\r
d7dec593	196	{\r
	197	EFI_STATUS Status;\r
	198	EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL *BootFvb;\r
	199	\r
	200	Status = GetFvbByAddress (BOOT_BLOCK_BASE, &BootFvb);\r
	201	if (EFI_ERROR (Status)) {\r
	202	return FALSE;\r
	203	}\r
	204	//\r
	205	// Compare the Fvb\r
	206	//\r
	207	return (BOOLEAN) (FvBlock == BootFvb);\r
	208	}\r
	209	\r
6aab8214	210	/**\r
	211	Copy the content of spare block to a boot block. Size is FTW_BLOCK_SIZE.\r
	212	Spare block is accessed by FTW backup FVB protocol interface. LBA is\r
	213	FtwLiteDevice->FtwSpareLba.\r
	214	Boot block is accessed by BootFvb protocol interface. LBA is 0.\r
	215	\r
	216	\r
	217	@param FtwLiteDevice The private data of FTW_LITE driver\r
	218	\r
	219	@retval EFI_SUCCESS Spare block content is copied to boot block\r
	220	@retval EFI_INVALID_PARAMETER Input parameter error\r
	221	@retval EFI_OUT_OF_RESOURCES Allocate memory error\r
	222	@retval EFI_ABORTED The function could not complete successfully\r
	223	Notes:\r
	224	FTW will do extra work on boot block update.\r
	225	FTW should depend on a protocol of EFI_ADDRESS_RANGE_SWAP_PROTOCOL,\r
	226	which is produced by a chipset driver.\r
	227	FTW updating boot block steps:\r
	228	1. Erase top swap block (0xFFFE-0xFFFEFFFF) and write data to it ready\r
	229	2. Read data from top swap block to memory buffer\r
	230	3. SetSwapState(EFI_SWAPPED)\r
	231	4. Erasing boot block (0xFFFF-0xFFFFFFFF)\r
	232	5. Programming boot block until the boot block is ok.\r
	233	6. SetSwapState(UNSWAPPED)\r
	234	Notes:\r
	235	1. Since the SwapState bit is saved in CMOS, FTW can restore and continue\r
	236	even in the scenario of power failure.\r
	237	2. FTW shall not allow to update boot block when battery state is error.\r
	238	\r
	239	**/\r
d7dec593	240	EFI_STATUS\r
	241	FlushSpareBlockToBootBlock (\r
	242	EFI_FTW_LITE_DEVICE *FtwLiteDevice\r
	243	)\r
d7dec593	244	{\r
	245	EFI_STATUS Status;\r
	246	UINTN Length;\r
	247	UINT8 *Buffer;\r
	248	UINTN Count;\r
	249	UINT8 *Ptr;\r
	250	UINTN Index;\r
	251	BOOLEAN TopSwap;\r
	252	EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL *BootFvb;\r
	253	EFI_LBA BootLba;\r
	254	\r
	255	//\r
	256	// Allocate a memory buffer\r
	257	//\r
	258	Length = FtwLiteDevice->SpareAreaLength;\r
	259	Buffer = AllocatePool (Length);\r
	260	if (Buffer == NULL) {\r
e11ae3a5	261	return EFI_OUT_OF_RESOURCES;\r
d7dec593	262	}\r
	263	//\r
	264	// Get TopSwap bit state\r
	265	//\r
	266	Status = GetSwapState (FtwLiteDevice, &TopSwap);\r
	267	if (EFI_ERROR (Status)) {\r
	268	DEBUG ((EFI_D_ERROR, "FtwLite: Get Top Swapped status - %r\n", Status));\r
	269	FreePool (Buffer);\r
	270	return EFI_ABORTED;\r
	271	}\r
	272	\r
	273	if (TopSwap) {\r
	274	//\r
	275	// Get FVB of current boot block\r
	276	//\r
	277	Status = GetFvbByAddress (FtwLiteDevice->SpareAreaAddress + FTW_BLOCK_SIZE, &BootFvb);\r
	278	if (EFI_ERROR (Status)) {\r
	279	FreePool (Buffer);\r
	280	return Status;\r
	281	}\r
	282	//\r
	283	// Read data from current boot block\r
	284	//\r
	285	BootLba = 0;\r
	286	Ptr = Buffer;\r
	287	for (Index = 0; Index < FtwLiteDevice->NumberOfSpareBlock; Index += 1) {\r
	288	Count = FtwLiteDevice->SizeOfSpareBlock;\r
	289	Status = BootFvb->Read (\r
	290	BootFvb,\r
	291	BootLba + Index,\r
	292	0,\r
	293	&Count,\r
	294	Ptr\r
	295	);\r
	296	if (EFI_ERROR (Status)) {\r
	297	FreePool (Buffer);\r
	298	return Status;\r
	299	}\r
	300	\r
	301	Ptr += Count;\r
	302	}\r
	303	\r
	304	} else {\r
	305	//\r
	306	// Read data from spare block\r
	307	//\r
	308	Ptr = Buffer;\r
	309	for (Index = 0; Index < FtwLiteDevice->NumberOfSpareBlock; Index += 1) {\r
	310	Count = FtwLiteDevice->SizeOfSpareBlock;\r
	311	Status = FtwLiteDevice->FtwBackupFvb->Read (\r
	312	FtwLiteDevice->FtwBackupFvb,\r
	313	FtwLiteDevice->FtwSpareLba + Index,\r
	314	0,\r
	315	&Count,\r
	316	Ptr\r
	317	);\r
	318	if (EFI_ERROR (Status)) {\r
	319	FreePool (Buffer);\r
	320	return Status;\r
	321	}\r
	322	\r
	323	Ptr += Count;\r
	324	}\r
	325	//\r
326	// Set TopSwap bit\r
327	//\r
328	Status = SetSwapState (FtwLiteDevice, TRUE);\r
329	DEBUG ((EFI_D_ERROR, "FtwLite: Set Swap State - %r\n", Status));\r
330	ASSERT_EFI_ERROR (Status);\r
331	}\r
332	//\r
333	// Erase boot block. After setting TopSwap bit, it's spare block now!\r
334	//\r
335	Status = FtwEraseSpareBlock (FtwLiteDevice);\r
336	if (EFI_ERROR (Status)) {\r
337	FreePool (Buffer);\r
338	return EFI_ABORTED;\r
339	}\r
340	//\r
341	// Write memory buffer to currenet spare block\r
342	//\r
343	Ptr = Buffer;\r
344	for (Index = 0; Index < FtwLiteDevice->NumberOfSpareBlock; Index += 1) {\r
345	Count = FtwLiteDevice->SizeOfSpareBlock;\r
346	Status = FtwLiteDevice->FtwBackupFvb->Write (\r
347	FtwLiteDevice->FtwBackupFvb,\r
348	FtwLiteDevice->FtwSpareLba + Index,\r
349	0,\r
350	&Count,\r
351	Ptr\r
352	);\r
353	if (EFI_ERROR (Status)) {\r
354	DEBUG ((EFI_D_FTW_LITE, "FtwLite: FVB Write boot block - %r\n", Status));\r
355	FreePool (Buffer);\r
356	return Status;\r
357	}\r
358	\r
359	Ptr += Count;\r
360	}\r
361	\r
362	FreePool (Buffer);\r
363	\r
364	//\r
365	// Clear TopSwap bit\r
366	//\r
367	Status = SetSwapState (FtwLiteDevice, FALSE);\r
368	DEBUG ((EFI_D_ERROR, "FtwLite: Clear Swap State - %r\n", Status));\r
369	ASSERT_EFI_ERROR (Status);\r
370	\r
371	return EFI_SUCCESS;\r
372	}\r