Re: [edk2-platforms][PATCH v1 1/1] IntelSiliconPkg: Add BaseSmmAccessLibNull

["Ni, Ray" <ray.ni@intel.com>]

Michael,
If your platform doesn't need SmmAccessPPI, you don't put the SmmAccess PEIM in the FDF.
Why do you need:
1. Put SmmAccess PEIM in FDF
2. Let SmmAccess PEIM link to a NULL dummy-do-nothing library

I feel the additional abstraction is not necessary.

Thanks,
Ray

> -----Original Message-----
> From: mikuback@linux.microsoft.com <mikuback@linux.microsoft.com>
> Sent: Monday, August 9, 2021 10:16 PM
> To: devel@edk2.groups.io
> Cc: Ni, Ray <ray.ni@intel.com>; Chaganty, Rangasai V <rangasai.v.chaganty@intel.com>
> Subject: [edk2-platforms][PATCH v1 1/1] IntelSiliconPkg: Add BaseSmmAccessLibNull
> 
> From: Michael Kubacki <michael.kubacki@microsoft.com>
> 
> REF:https://bugzilla.tianocore.org/show_bug.cgi?id=3540
> 
> Adds a NULL instance of SmmAccessLib.
> 
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Rangasai V Chaganty <rangasai.v.chaganty@intel.com>
> Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
> ---
>  Silicon/Intel/IntelSiliconPkg/Feature/SmmAccess/Library/BaseSmmAccessLibNull/BaseSmmAccessLibNull.c   | 33
> ++++++++++++++++++++
>  Silicon/Intel/IntelSiliconPkg/Feature/SmmAccess/Library/BaseSmmAccessLibNull/BaseSmmAccessLibNull.inf | 26
> +++++++++++++++
>  Silicon/Intel/IntelSiliconPkg/IntelSiliconPkg.dsc                                                     |  1 +
>  3 files changed, 60 insertions(+)
> 
> diff --git a/Silicon/Intel/IntelSiliconPkg/Feature/SmmAccess/Library/BaseSmmAccessLibNull/BaseSmmAccessLibNull.c
> b/Silicon/Intel/IntelSiliconPkg/Feature/SmmAccess/Library/BaseSmmAccessLibNull/BaseSmmAccessLibNull.c
> new file mode 100644
> index 000000000000..f5ad306b380b
> --- /dev/null
> +++ b/Silicon/Intel/IntelSiliconPkg/Feature/SmmAccess/Library/BaseSmmAccessLibNull/BaseSmmAccessLibNull.c
> @@ -0,0 +1,33 @@
> +/** @file
> +  A NULL library instance of SmmAccessLib.
> +
> +  Copyright (c) 2019 - 2020, Intel Corporation. All rights reserved.<BR>
> +  Copyright (c) Microsoft Corporation.<BR>
> +
> +  SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#include <Uefi.h>
> +#include <Library/DebugLib.h>
> +#include <Library/SmmAccessLib.h>
> +
> +/**
> +  This function is to install an SMM Access PPI
> +
> +  @retval EFI_SUCCESS           - Ppi successfully started and installed.
> +  @retval EFI_NOT_FOUND         - Ppi can't be found.
> +  @retval EFI_OUT_OF_RESOURCES  - Ppi does not have enough resources to initialize the driver.
> +  @retval EFI_UNSUPPORTED       - The PPI was not installed and installation is unsupported in
> +                                  this instance of function implementation.
> +
> +**/
> +EFI_STATUS
> +EFIAPI
> +PeiInstallSmmAccessPpi (
> +  VOID
> +  )
> +{
> +  ASSERT (FALSE);
> +  return EFI_UNSUPPORTED;
> +}
> diff --git a/Silicon/Intel/IntelSiliconPkg/Feature/SmmAccess/Library/BaseSmmAccessLibNull/BaseSmmAccessLibNull.inf
> b/Silicon/Intel/IntelSiliconPkg/Feature/SmmAccess/Library/BaseSmmAccessLibNull/BaseSmmAccessLibNull.inf
> new file mode 100644
> index 000000000000..7fd3b0b89655
> --- /dev/null
> +++ b/Silicon/Intel/IntelSiliconPkg/Feature/SmmAccess/Library/BaseSmmAccessLibNull/BaseSmmAccessLibNull.inf
> @@ -0,0 +1,26 @@
> +## @file
> +# A NULL library instance of SmmAccessLib.
> +#
> +# Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
> +# Copyright (c) Microsoft Corporation.<BR>
> +# SPDX-License-Identifier: BSD-2-Clause-Patent
> +#
> +##
> +
> +[Defines]
> +INF_VERSION     = 0x00010017
> +BASE_NAME       = BaseSmmAccessLibNull
> +FILE_GUID       = C1A14AB6-B757-4046-9B92-9DCE1A2154C6
> +VERSION_STRING  = 1.0
> +MODULE_TYPE     = BASE
> +LIBRARY_CLASS   = SmmAccessLib
> +
> +[Packages]
> +  MdePkg/MdePkg.dec
> +  IntelSiliconPkg/IntelSiliconPkg.dec
> +
> +[LibraryClasses]
> +  DebugLib
> +
> +[Sources]
> +  BaseSmmAccessLibNull.c
> diff --git a/Silicon/Intel/IntelSiliconPkg/IntelSiliconPkg.dsc b/Silicon/Intel/IntelSiliconPkg/IntelSiliconPkg.dsc
> index 1092371d848e..dd0928ec58f3 100644
> --- a/Silicon/Intel/IntelSiliconPkg/IntelSiliconPkg.dsc
> +++ b/Silicon/Intel/IntelSiliconPkg/IntelSiliconPkg.dsc
> @@ -90,6 +90,7 @@ [Components]
>    IntelSiliconPkg/Feature/Capsule/MicrocodeUpdateDxe/MicrocodeUpdateDxe.inf
>    IntelSiliconPkg/Feature/Capsule/Library/MicrocodeFlashAccessLibNull/MicrocodeFlashAccessLibNull.inf
>    IntelSiliconPkg/Feature/ShadowMicrocode/ShadowMicrocodePei.inf
> +  IntelSiliconPkg/Feature/SmmAccess/Library/BaseSmmAccessLibNull/BaseSmmAccessLibNull.inf
>    IntelSiliconPkg/Library/PeiDxeSmmBootMediaLib/PeiFirmwareBootMediaLib.inf
>    IntelSiliconPkg/Library/PeiDxeSmmBootMediaLib/DxeSmmFirmwareBootMediaLib.inf
>    IntelSiliconPkg/Library/DxeAslUpdateLib/DxeAslUpdateLib.inf
> --
> 2.28.0.windows.1