Re: [edk2-devel] [Patch] [edk2-platforms] AdvancedFeaturePkg/Cmos: Add Cmos related libraries.

["Liming Gao" <liming.gao@intel.com>]

Eric:
  Now, edk2-platform devel-MinPlatform branch has merged into edk2-platform master branch.

  For this change, I propose to add new GenericBoardPkg in Platform\Intel directory for the common board features. 

Thanks
Liming
> -----Original Message-----
> From: devel@edk2.groups.io [mailto:devel@edk2.groups.io] On Behalf Of Dong, Eric
> Sent: Tuesday, May 7, 2019 3:31 PM
> To: devel@edk2.groups.io
> Cc: Ni, Ray <ray.ni@intel.com>; Kubacki, Michael A <michael.a.kubacki@intel.com>; Desimone, Nathaniel L
> <nathaniel.l.desimone@intel.com>
> Subject: [edk2-devel] [Patch] [edk2-platforms] AdvancedFeaturePkg/Cmos: Add Cmos related libraries.
> 
> https://bugzilla.tianocore.org/show_bug.cgi?id=1552
> 
> Add two libraries used to provide CMOS related operation.
> 
> CmosAccessLib exports below APIs:
>   CmosWrite32
>   CmosWrite16
>   CmosWrite8
>   CmosRead32
>   CmosRead16
>   CmosRead8
>   CmosInit
> 
> PlatformCmosAccessLib export below APIs:
>   PlatformCmosGetEntry
>   PlatformCmosGetNmiState
> 
> PlatformCmosAccessLib will be consumed by CmosAccessLib.
> 
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Michael Kubacki <michael.a.kubacki@intel.com>
> Cc: Nate Desimone <nathaniel.l.desimone@intel.com>
> Signed-off-by: Eric Dong <eric.dong@intel.com>
> ---
>  .../Cmos/Include/Library/CmosAccessLib.h      | 112 ++++
>  .../Include/Library/PlatformCmosAccessLib.h   |  74 +++
>  .../Library/CmosAccessLib/CmosAccessLib.c     | 492 ++++++++++++++++++
>  .../Library/CmosAccessLib/CmosAccessLib.inf   |  34 ++
>  .../CmosAccessLib/CmosAccessLibInternal.h     |  41 ++
>  .../PlatformCmosAccessLibNull.c               |  45 ++
>  .../PlatformCmosAccessLibNull.inf             |  30 ++
>  7 files changed, 828 insertions(+)
>  create mode 100644 Platform/Intel/AdvancedFeaturePkg/Cmos/Include/Library/CmosAccessLib.h
>  create mode 100644 Platform/Intel/AdvancedFeaturePkg/Cmos/Include/Library/PlatformCmosAccessLib.h
>  create mode 100644 Platform/Intel/AdvancedFeaturePkg/Cmos/Library/CmosAccessLib/CmosAccessLib.c
>  create mode 100644 Platform/Intel/AdvancedFeaturePkg/Cmos/Library/CmosAccessLib/CmosAccessLib.inf
>  create mode 100644 Platform/Intel/AdvancedFeaturePkg/Cmos/Library/CmosAccessLib/CmosAccessLibInternal.h
>  create mode 100644 Platform/Intel/AdvancedFeaturePkg/Cmos/Library/PlatformCmosAccessLibNull/PlatformCmosAccessLibNull.c
>  create mode 100644 Platform/Intel/AdvancedFeaturePkg/Cmos/Library/PlatformCmosAccessLibNull/PlatformCmosAccessLibNull.inf
> 
> diff --git a/Platform/Intel/AdvancedFeaturePkg/Cmos/Include/Library/CmosAccessLib.h
> b/Platform/Intel/AdvancedFeaturePkg/Cmos/Include/Library/CmosAccessLib.h
> new file mode 100644
> index 0000000..5f5029c
> --- /dev/null
> +++ b/Platform/Intel/AdvancedFeaturePkg/Cmos/Include/Library/CmosAccessLib.h
> @@ -0,0 +1,112 @@
> +/** @file
> +  CmosAccessLib header file.
> +
> +Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
> +This program and the accompanying materials are licensed and made available under
> +the terms and conditions of the BSD License that 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.
> +
> +**/
> +
> +#ifndef _CMOS_ACCESS_LIB_H_
> +#define _CMOS_ACCESS_LIB_H_
> +
> +/**
> +  Read a byte value from a CMOS address.
> +
> +  @param [in] Address   Location to read from CMOS
> +
> +  @return The byte value read from the CMOS address.
> +**/
> +UINT8
> +EFIAPI
> +CmosRead8 (
> +  IN  UINT8 Address
> +  );
> +
> +/**
> +  Write a byte value to a CMOS address.
> +
> +  @param [in] Address Location to write to CMOS.
> +  @param [in] Data    The byte value write to the CMOS address.
> +**/
> +VOID
> +EFIAPI
> +CmosWrite8 (
> +  IN UINT8 Address,
> +  IN UINT8 Data
> +  );
> +
> +/**
> +  Read a word value from a CMOS address.
> +
> +  @param [in] Address   Location to read from CMOS
> +
> +  @return The word value read from the CMOS address.
> +**/
> +UINT16
> +EFIAPI
> +CmosRead16 (
> +  IN  UINT8  Address
> +  );
> +
> +/**
> +  Write a word value to a CMOS address.
> +
> +  @param [in] Address Location to write to CMOS.
> +  @param [in] Data    The word value write to the CMOS address.
> +**/
> +VOID
> +EFIAPI
> +CmosWrite16 (
> +  IN UINT8  Address,
> +  IN UINT16 Data
> +  );
> +
> +/**
> +  Read a dword value from a CMOS address.
> +
> +  @param [in] Address   Location to read from CMOS
> +
> +  @return The dword value read from the CMOS address.
> +**/
> +UINT32
> +EFIAPI
> +CmosRead32 (
> +  IN  UINT8  Address
> +  );
> +
> +/**
> +  Write a dword value to a CMOS address.
> +
> +  @param [in] Address Location to write to CMOS.
> +  @param [in] Data    The dword value write to the CMOS address.
> +**/
> +VOID
> +EFIAPI
> +CmosWrite32 (
> +  IN UINT8  Address,
> +  IN UINT32 Data
> +  );
> +
> +/**
> +  Initialize the CMOS.
> +
> +  It initialize the CMOS area when Force is TRUE or the checksum is incorrect.
> +
> +  @param[in]  Force  TRUE indicating initializing the CMOS area without checking the checksum.
> +
> +  @retval TRUE  The CMOS is initialized to default value.
> +  @retval FALSE The CMOS isn't initialized to default value.
> +**/
> +BOOLEAN
> +EFIAPI
> +CmosInit (
> +  IN  BOOLEAN     Force
> +  );
> +
> +#endif // _CMOS_ACCESS_LIB_H_
> diff --git a/Platform/Intel/AdvancedFeaturePkg/Cmos/Include/Library/PlatformCmosAccessLib.h
> b/Platform/Intel/AdvancedFeaturePkg/Cmos/Include/Library/PlatformCmosAccessLib.h
> new file mode 100644
> index 0000000..8c44ae2
> --- /dev/null
> +++ b/Platform/Intel/AdvancedFeaturePkg/Cmos/Include/Library/PlatformCmosAccessLib.h
> @@ -0,0 +1,74 @@
> +/** @file
> +  Platform CMOS Access Library Header File.
> +
> +Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
> +This program and the accompanying materials are licensed and made available under
> +the terms and conditions of the BSD License that 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.
> +
> +**/
> +
> +#ifndef _PLATFORM_CMOS_ACCESS_LIB_H_
> +#define _PLATFORM_CMOS_ACCESS_LIB_H_
> +
> +///
> +/// Flag indicating checksum calculation doesn't include this location.
> +/// NOTE: If a location isn't shown in platform CMOS entry table,
> +///       it means checksum calculation doesn't include the location.
> +///
> +#define CMOS_EXCLUDE_FROM_CHECKSUM    BIT0
> +
> +///
> +/// Flag indicating initialization doesn't cover this location.
> +/// NOTE: If a location isn't shown in platform CMOS entry table,
> +///       it means the location is initialized with CMOS_DEFAULT_VALUE (0).
> +///
> +#define CMOS_EXCLUDE_FROM_INIT_DATA   BIT1
> +
> +///
> +/// Flag indicating the location cannot be accessed.
> +/// NOTE: 0x0 ~ 0xD is implictly inaccessible.
> +///
> +#define CMOS_EXCLUDE_FROM_ACCESS      (BIT3 | CMOS_EXCLUDE_FROM_CHECKSUM | CMOS_EXCLUDE_FROM_INIT_DATA)
> +
> +///
> +/// Flag indicating the checksum location
> +/// NOTE: At most two entries can have this flag set.
> +///
> +#define CMOS_CHECKSUM_LOCATION        (BIT2 | CMOS_EXCLUDE_FROM_CHECKSUM | CMOS_EXCLUDE_FROM_INIT_DATA)
> +
> +#define CMOS_DEFAULT_VALUE            0x00
> +
> +typedef struct {
> +  UINT8 Address;
> +  UINT8 DefaultValue;
> +  UINT8 Attributes;
> +} CMOS_ENTRY;
> +
> +/**
> +  Return the platform CMOS entries.
> +
> +  @param [out] EntryCount Return the count of platform CMOS entries.
> +
> +  @return Platform CMOS entries.
> +**/
> +CMOS_ENTRY *
> +EFIAPI
> +PlatformCmosGetEntry (
> +  OUT UINTN       *EntryCount
> +  );
> +
> +/**
> +  Return the NMI enable status.
> +**/
> +BOOLEAN
> +EFIAPI
> +PlatformCmosGetNmiState (
> +  VOID
> +  );
> +
> +#endif // _PLATFORM_CMOS_ACCESS_LIB_H_
> diff --git a/Platform/Intel/AdvancedFeaturePkg/Cmos/Library/CmosAccessLib/CmosAccessLib.c
> b/Platform/Intel/AdvancedFeaturePkg/Cmos/Library/CmosAccessLib/CmosAccessLib.c
> new file mode 100644
> index 0000000..403d8ff
> --- /dev/null
> +++ b/Platform/Intel/AdvancedFeaturePkg/Cmos/Library/CmosAccessLib/CmosAccessLib.c
> @@ -0,0 +1,492 @@
> +/** @file
> +  CmosAccessLib implementation.
> +
> +Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
> +This program and the accompanying materials are licensed and made available under
> +the terms and conditions of the BSD License that 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 "CmosAccessLibInternal.h"
> +
> +/**
> +  Return the entry for the specified address in entries returned
> +  from platform.
> +
> +  @param [in] Address  The CMOS address to find.
> +
> +  @return A pointer to CMOS_ENTRY for the specified address,
> +          or NULL if not found.
> +**/
> +CMOS_ENTRY *
> +CmosAccessLibLocateEntry (
> +  IN UINT8      Address
> +  )
> +{
> +  UINTN              Index;
> +  UINTN              Count;
> +  CMOS_ENTRY         *Entries;
> +
> +  Entries = PlatformCmosGetEntry (&Count);
> +  for (Index = 0; Index < Count; Index++) {
> +    if (Entries[Index].Address == Address) {
> +      return &Entries[Index];
> +    }
> +  }
> +
> +  return NULL;
> +}
> +
> +/**
> +  Test the attributes of the Entry and return ValueIfSet if test passes
> +  or !ValueIfSet if test fails. It returns DefaultValue if the Entry is
> +  NULL.
> +
> +  @param [in] Address      The CMOS address.
> +  @param [in] Attributes   The attributes to test.
> +  @param [in] ValueIfSet   The value to return if test passes.
> +  @param [in] DefaultValue The value to return if Entry is NULL.
> +  @param [in] Entry        Pointer to entry.
> +
> +  @retval ValueIfSet   If test passes.
> +  @retval !ValueIfSet  If test fails.
> +  @retval DefaultValue If the Entry is NULL.
> +**/
> +BOOLEAN
> +CmosAccessLibCheckAttribute (
> +  IN UINT8      Address,
> +  IN UINT8      Attributes,
> +  IN BOOLEAN    ValueIfSet,
> +  IN BOOLEAN    DefaultValue,
> +  IN CMOS_ENTRY *Entry        OPTIONAL
> +  )
> +{
> +  if (Entry != NULL) {
> +    ASSERT (Entry->Address == Address);
> +    if ((Entry->Attributes & Attributes) == Attributes) {
> +      return ValueIfSet;
> +    } else {
> +      return !ValueIfSet;
> +    }
> +  }
> +
> +  return DefaultValue;
> +}
> +
> +/**
> +  Check if the CMOS address needs Checksum calculation.
> +
> +  @param [in] Address CMOS address to be checked
> +  @param [in] Entry   Pointer to entry.
> +
> +  @retval TRUE       CMOS address needs Checksum calculation.
> +  @retval FALSE      CMOS address doesn't need Checksum calculation.
> +**/
> +BOOLEAN
> +CmosAccessLibNeedChecksum (
> +  IN UINT8       Address,
> +  IN CMOS_ENTRY  *Entry OPTIONAL
> +  )
> +{
> +  return CmosAccessLibCheckAttribute (Address, CMOS_EXCLUDE_FROM_CHECKSUM, FALSE, FALSE, Entry);
> +}
> +
> +
> +/**
> +  Check if the CMOS address needs to fill default data.
> +
> +  @param [in] Address CMOS address to be checked
> +  @param [in] Entry   Pointer to entry.
> +
> +  @retval TRUE       CMOS address need to fill default data.
> +  @retval FALSE      CMOS address doesn't need to fill default data.
> +**/
> +BOOLEAN
> +CmosAccessLibNeedFillDefault (
> +  IN UINT8       Address,
> +  IN CMOS_ENTRY  *Entry OPTIONAL
> +  )
> +{
> +  return CmosAccessLibCheckAttribute (Address, CMOS_EXCLUDE_FROM_INIT_DATA, FALSE, TRUE, Entry);
> +}
> +
> +/**
> +  Check if the CMOS address is accessible.
> +
> +  @param [in] Address CMOS address to be checked.
> +  @param [in] Entry   Pointer to entry.
> +
> +  @retval TRUE       CMOS address is accessible.
> +  @retval FALSE      CMOS address isn't accessible.
> +**/
> +BOOLEAN
> +CmosAccessLibIsAccessible (
> +  IN UINT8       Address,
> +  IN CMOS_ENTRY  *Entry OPTIONAL
> +  )
> +{
> +  //
> +  // CMOS 0-9, A, B, C, D are for RTC.
> +  //
> +  if (Address <= 0xD) {
> +    return FALSE;
> +  }
> +  return CmosAccessLibCheckAttribute (Address, CMOS_EXCLUDE_FROM_ACCESS, FALSE, TRUE, Entry);
> +}
> +
> +/**
> +  Return the CMOS location to store checksum.
> +
> +  @param [out] Location Return the CMOS location to store the checksum.
> +**/
> +VOID
> +CmosAccessLibGetChecksumLocation (
> +  OUT CMOS_CHECKSUM_LOCATION_INFO *Location
> +  )
> +{
> +  UINTN                       Index;
> +  UINTN                       Count;
> +  CMOS_ENTRY                  *Entries;
> +
> +  Location->Length = 0;
> +
> +  Entries = PlatformCmosGetEntry (&Count);
> +  for (Index = 0; Index < Count; Index++) {
> +    if ((Entries[Index].Attributes & CMOS_CHECKSUM_LOCATION) == CMOS_CHECKSUM_LOCATION) {
> +      Location->Length++;
> +      if (Location->Length == 1) {
> +        Location->LowByteAddress = Entries[Index].Address;
> +      } else if (Location->Length == 2) {
> +        Location->HighByteAddress = Entries[Index].Address;
> +        break;
> +      }
> +    }
> +  }
> +
> +  ASSERT (Location->Length <= 2);
> +}
> +
> +/**
> +  Calculate the sum of CMOS values who need checksum calculation.
> +
> +  @param [in] Location The CMOS location to store the checksum.
> +
> +  @return The sum.
> +**/
> +UINT16
> +CmosAccessLibCalculateSum (
> +  IN CMOS_CHECKSUM_LOCATION_INFO *Location
> +  )
> +{
> +  UINT16                      Sum;
> +  UINTN                       Index;
> +  UINTN                       Count;
> +  CMOS_ENTRY                  *Entries;
> +
> +  if (Location->Length == 0) {
> +    return 0;
> +  }
> +
> +  Sum = 0;
> +  Entries = PlatformCmosGetEntry (&Count);
> +  for (Index = 0; Index < Count; Index++) {
> +    if (CmosAccessLibNeedChecksum (Entries[Index].Address, &Entries[Index])) {
> +      Sum += CmosRead8 (Entries[Index].Address);
> +    }
> +  }
> +
> +  if (Location->Length == 1) {
> +    return (UINT8) Sum;
> +  } else {
> +    return Sum;
> +  }
> +}
> +
> +/**
> +  Return the checksum value stored in CMOS.
> +
> +  @param [in] Location The CMOS location to store the checksum.
> +
> +  @return The checksum value.
> +**/
> +UINT16
> +CmosAccessLibReadChecksum (
> +  IN CMOS_CHECKSUM_LOCATION_INFO *Location
> +  )
> +{
> +  UINT16                      Checksum;
> +
> +  Checksum = 0;
> +
> +  switch (Location->Length) {
> +  case 2:
> +    Checksum = (CmosRead8 (Location->HighByteAddress) << 8);
> +    //
> +    // Fall to case 1 to get the low byte value
> +    //
> +  case 1:
> +    Checksum += CmosRead8 (Location->LowByteAddress);
> +    break;
> +
> +  default:
> +    break;
> +  }
> +  return Checksum;
> +}
> +
> +
> +/**
> +  Write the Checksum to appropriate address.
> +
> +  @param [in] Location The CMOS location to store the checksum.
> +  @param [in] Checksum The checksum value.
> +**/
> +VOID
> +CmosAccessLibWriteChecksum (
> +  CMOS_CHECKSUM_LOCATION_INFO *Location,
> +  IN UINT16                   Checksum
> +  )
> +{
> +
> +  switch (Location->Length) {
> +  case 0:
> +    break;
> +  case 2:
> +    CmosWrite8 (Location->HighByteAddress, Checksum >> 8);
> +    //
> +    // Fall to case 1 to update low byte value
> +    //
> +  case 1:
> +    CmosWrite8 (Location->LowByteAddress, (UINT8) Checksum);
> +    break;
> +  }
> +}
> +
> +/**
> +  Read a byte value from a CMOS address.
> +
> +  @param [in] Address   Location to read from CMOS
> +
> +  @return The byte value read from the CMOS address.
> +**/
> +UINT8
> +EFIAPI
> +CmosRead8 (
> +  IN  UINT8 Address
> +  )
> +{
> +  if (!CmosAccessLibIsAccessible (Address, CmosAccessLibLocateEntry (Address))) {
> +    return 0xFF;
> +  }
> +
> +  if (Address <= CMOS_BANK0_LIMIT) {
> +    if (PlatformCmosGetNmiState ()) {
> +      Address |= BIT7;
> +    }
> +    IoWrite8 (PORT_70, Address);
> +    return IoRead8 (PORT_71);
> +  } else {
> +    IoWrite8 (PORT_72, Address);
> +    return IoRead8 (PORT_73);
> +  }
> +}
> +
> +/**
> +  Write a byte value to a CMOS address.
> +
> +  It's an internal function that doesn't update the checksum.
> +
> +  @param [in] Address Location to write to CMOS.
> +  @param [in] Data    The byte value write to the CMOS address.
> +**/
> +VOID
> +CmosAccessLibICmosWrite8 (
> +  IN UINT8 Address,
> +  IN UINT8 Data
> +  )
> +{
> +  if (Address <= CMOS_BANK0_LIMIT) {
> +    if (PlatformCmosGetNmiState ()) {
> +      Address |= BIT7;
> +    }
> +    IoWrite8 (PORT_70, Address);
> +    IoWrite8 (PORT_71, Data);
> +  } else {
> +    IoWrite8 (PORT_72, Address);
> +    IoWrite8 (PORT_73, Data);
> +  }
> +}
> +
> +/**
> +  Write a byte value to a CMOS address.
> +
> +  @param [in] Address Location to write to CMOS.
> +  @param [in] Data    The byte value write to the CMOS address.
> +**/
> +VOID
> +EFIAPI
> +CmosWrite8 (
> +  IN UINT8 Address,
> +  IN UINT8 Data
> +  )
> +{
> +  UINT8                       OriginalData;
> +  CMOS_ENTRY                  *Entry;
> +  CMOS_CHECKSUM_LOCATION_INFO ChecksumLocation;
> +
> +  Entry = CmosAccessLibLocateEntry (Address);
> +
> +  if (!CmosAccessLibIsAccessible (Address, Entry)) {
> +    return;
> +  }
> +
> +  OriginalData = CmosRead8 (Address);
> +
> +  CmosAccessLibICmosWrite8 (Address, Data);
> +
> +  if (CmosAccessLibNeedChecksum (Address, Entry)) {
> +    //
> +    // Sum of Data + Checksum = New Sum of Data + New Checksum = 0
> +    // New Sum of Data - Sum of Data = Checksum - New Checksum
> +    // New Checksum = Checksum - (New Sum of Data - Sum of Data)
> +    //
> +    CmosAccessLibGetChecksumLocation (&ChecksumLocation);
> +    CmosAccessLibWriteChecksum (
> +      &ChecksumLocation,
> +      CmosAccessLibReadChecksum (&ChecksumLocation) - (Data - OriginalData)
> +      );
> +  }
> +}
> +
> +/**
> +  Read a word value from a CMOS address.
> +
> +  @param [in] Address   Location to read from CMOS
> +
> +  @return The word value read from the CMOS address.
> +**/
> +UINT16
> +EFIAPI
> +CmosRead16 (
> +  IN  UINT8  Address
> +  )
> +{
> +  return CmosRead8 (Address) + (CmosRead8 (Address + 1) << 8);
> +}
> +
> +/**
> +  Write a word value to a CMOS address.
> +
> +  @param [in] Address Location to write to CMOS.
> +  @param [in] Data    The word value write to the CMOS address.
> +**/
> +VOID
> +EFIAPI
> +CmosWrite16 (
> +  IN UINT8  Address,
> +  IN UINT16 Data
> +  )
> +{
> +  CmosWrite8 (Address, (UINT8) Data);
> +  CmosWrite8 (Address + 1, (UINT8) (Data >> 8));
> +}
> +
> +/**
> +  Read a dword value from a CMOS address.
> +
> +  @param [in] Address   Location to read from CMOS
> +
> +  @return The dword value read from the CMOS address.
> +**/
> +UINT32
> +EFIAPI
> +CmosRead32 (
> +  IN  UINT8  Address
> +  )
> +{
> +  return CmosRead16 (Address) + (CmosRead16 (Address + 2) << 16);
> +}
> +
> +/**
> +  Write a dword value to a CMOS address.
> +
> +  @param [in] Address Location to write to CMOS.
> +  @param [in] Data    The dword value write to the CMOS address.
> +**/
> +VOID
> +EFIAPI
> +CmosWrite32 (
> +  IN UINT8  Address,
> +  IN UINT32 Data
> +  )
> +{
> +  CmosWrite16 (Address, (UINT16) Data);
> +  CmosWrite16 (Address + 2, (UINT16) (Data >> 16));
> +}
> +
> +
> +/**
> +  Initialize the CMOS.
> +
> +  It initialize the CMOS area when Force is TRUE or the checksum is incorrect.
> +
> +  @param[in]  Force  TRUE indicating initializing the CMOS area without checking the checksum.
> +
> +  @retval TRUE  The CMOS is initialized to default value.
> +  @retval FALSE The CMOS isn't initialized to default value.
> +**/
> +BOOLEAN
> +EFIAPI
> +CmosInit (
> +  IN  BOOLEAN     Force
> +  )
> +{
> +  UINTN                       Address;
> +  CMOS_ENTRY                  *Entry;
> +  CMOS_CHECKSUM_LOCATION_INFO ChecksumLocation;
> +  UINT16                      Checksum;
> +
> +  CmosAccessLibGetChecksumLocation (&ChecksumLocation);
> +
> +  if (!Force) {
> +    //
> +    // Initialize the CMOS area when checksum is incorrect.
> +    //
> +    Checksum = CmosAccessLibCalculateSum (&ChecksumLocation) + CmosAccessLibReadChecksum (&ChecksumLocation);
> +    if (ChecksumLocation.Length == 1) {
> +      Checksum = (UINT8) Checksum;
> +    }
> +
> +    if (Checksum != 0) {
> +      Force = TRUE;
> +    }
> +  }
> +
> +  if (Force) {
> +    //
> +    // Traverse through entire CMOS location and fill it with zero
> +    //
> +    for (Address = 0; Address <= CMOS_BANK1_LIMIT; Address++) {
> +      Entry = CmosAccessLibLocateEntry ((UINT8) Address);
> +      if (CmosAccessLibNeedFillDefault ((UINT8) Address, Entry)) {
> +        CmosAccessLibICmosWrite8 ((UINT8) Address, (Entry == NULL) ? CMOS_DEFAULT_VALUE : Entry->DefaultValue);
> +      }
> +    }
> +
> +    //
> +    // Write the New checksum to the Checksum field
> +    //
> +    CmosAccessLibWriteChecksum (
> +      &ChecksumLocation,
> +      (UINT16) (0x10000 - CmosAccessLibCalculateSum (&ChecksumLocation))
> +      );
> +    return TRUE;
> +  }
> +
> +  return FALSE;
> +}
> diff --git a/Platform/Intel/AdvancedFeaturePkg/Cmos/Library/CmosAccessLib/CmosAccessLib.inf
> b/Platform/Intel/AdvancedFeaturePkg/Cmos/Library/CmosAccessLib/CmosAccessLib.inf
> new file mode 100644
> index 0000000..9decaf4
> --- /dev/null
> +++ b/Platform/Intel/AdvancedFeaturePkg/Cmos/Library/CmosAccessLib/CmosAccessLib.inf
> @@ -0,0 +1,34 @@
> +### @file
> +# Library producing CMOS access functionality.
> +#
> +# Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
> +#
> +# 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.
> +#
> +###
> +[Defines]
> +  INF_VERSION    = 0x00010005
> +  BASE_NAME      = CmosAccessLib
> +  FILE_GUID      = FF6B645D-C001-4ACE-9CA1-199F97C2D601
> +  VERSION_STRING = 1.0
> +  MODULE_TYPE    = BASE
> +  LIBRARY_CLASS  = CmosAccessLib
> +
> +[Sources]
> +  CmosAccessLib.c
> +  CmosAccessLibInternal.h
> +
> +[LibraryClasses]
> +  IoLib
> +  DebugLib
> +  PlatformCmosAccessLib
> +
> +[Packages]
> +  MdePkg/MdePkg.dec
> +  AdvancedFeaturePkg/AdvancedFeaturePkg.dec
> \ No newline at end of file
> diff --git a/Platform/Intel/AdvancedFeaturePkg/Cmos/Library/CmosAccessLib/CmosAccessLibInternal.h
> b/Platform/Intel/AdvancedFeaturePkg/Cmos/Library/CmosAccessLib/CmosAccessLibInternal.h
> new file mode 100644
> index 0000000..9b6d086
> --- /dev/null
> +++ b/Platform/Intel/AdvancedFeaturePkg/Cmos/Library/CmosAccessLib/CmosAccessLibInternal.h
> @@ -0,0 +1,41 @@
> +/** @file
> +  CmosAccessLib internal header file.
> +
> +Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
> +This program and the accompanying materials are licensed and made available under
> +the terms and conditions of the BSD License that 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.
> +
> +**/
> +
> +#ifndef _CMOS_ACCESS_LIB_INTERNALS_
> +#define _CMOS_ACCESS_LIB_INTERNALS_
> +
> +#include <Base.h>
> +#include <Uefi.h>
> +#include <Library/IoLib.h>
> +#include <Library/DebugLib.h>
> +#include <Library/CmosAccessLib.h>
> +#include <Library/PlatformCmosAccessLib.h>
> +
> +// CMOS access Port address
> +
> +#define PORT_70            0x70
> +#define PORT_71            0x71
> +#define PORT_72            0x72
> +#define PORT_73            0x73
> +
> +#define CMOS_BANK0_LIMIT   0x7F
> +#define CMOS_BANK1_LIMIT   0xFF
> +
> +typedef struct {
> +   UINT8  Length;
> +   UINT8  LowByteAddress;
> +   UINT8  HighByteAddress;
> +} CMOS_CHECKSUM_LOCATION_INFO;
> +
> +#endif // _CMOS_ACCESS_LIB_INTERNALS_
> diff --git a/Platform/Intel/AdvancedFeaturePkg/Cmos/Library/PlatformCmosAccessLibNull/PlatformCmosAccessLibNull.c
> b/Platform/Intel/AdvancedFeaturePkg/Cmos/Library/PlatformCmosAccessLibNull/PlatformCmosAccessLibNull.c
> new file mode 100644
> index 0000000..b24a3f5
> --- /dev/null
> +++ b/Platform/Intel/AdvancedFeaturePkg/Cmos/Library/PlatformCmosAccessLibNull/PlatformCmosAccessLibNull.c
> @@ -0,0 +1,45 @@
> +/** @file
> +  Platform CMOS Access Library.
> +
> +Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
> +This program and the accompanying materials are licensed and made available under
> +the terms and conditions of the BSD License that 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 <Base.h>
> +#include <Library/PlatformCmosAccessLib.h>
> +
> +/**
> +  Return the platform CMOS entries.
> +
> +  @param [out] EntryCount Return the count of platform CMOS entries.
> +
> +  @return Platform CMOS entries.
> +**/
> +CMOS_ENTRY *
> +EFIAPI
> +PlatformCmosGetEntry (
> +  OUT UINTN       *EntryCount
> +  )
> +{
> +  *EntryCount = 0;
> +  return NULL;
> +}
> +
> +/**
> +  Return the NMI enable status.
> +**/
> +BOOLEAN
> +EFIAPI
> +PlatformCmosGetNmiState (
> +  VOID
> +  )
> +{
> +  return FALSE;
> +}
> diff --git a/Platform/Intel/AdvancedFeaturePkg/Cmos/Library/PlatformCmosAccessLibNull/PlatformCmosAccessLibNull.inf
> b/Platform/Intel/AdvancedFeaturePkg/Cmos/Library/PlatformCmosAccessLibNull/PlatformCmosAccessLibNull.inf
> new file mode 100644
> index 0000000..4816464
> --- /dev/null
> +++ b/Platform/Intel/AdvancedFeaturePkg/Cmos/Library/PlatformCmosAccessLibNull/PlatformCmosAccessLibNull.inf
> @@ -0,0 +1,30 @@
> +### @file
> +# Library producing CMOS access functionalities are relevant to platform.
> +#
> +# Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
> +#
> +# 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.
> +#
> +###
> +
> +[Defines]
> +  INF_VERSION    = 0x00010005
> +  BASE_NAME      = PlatformCmosAccessLib
> +  FILE_GUID      = C315A8B6-FF6C-41D1-A934-7330501F308C
> +  VERSION_STRING = 1.0
> +  MODULE_TYPE    = BASE
> +  LIBRARY_CLASS  = PlatformCmosAccessLib
> +
> +
> +[Sources]
> +  PlatformCmosAccessLibNull.c
> +
> +[Packages]
> +  MdePkg/MdePkg.dec
> +  AdvancedFeaturePkg/AdvancedFeaturePkg.dec
> \ No newline at end of file
> --
> 2.21.0.windows.1
> 
> 
>