Re: [PATCH v2 3/4] UefiCpuPkg/SmmCpuFeaturesLib: Abstract PcdCpuMaxLogicalProcessorNumber

["Laszlo Ersek" <lersek@redhat.com>]

On 02/13/21 01:58, mikuback@linux.microsoft.com wrote:
> From: Michael Kubacki <michael.kubacki@microsoft.com>
> 
> REF:https://bugzilla.tianocore.org/show_bug.cgi?id=3218
> 
> Adds a new function called GetCpuMaxLogicalProcessorNumber() to
> return the number of maximum CPU logical processors (currently
> gUefiCpuPkgTokenSpaceGuid.PcdCpuMaxLogicalProcessorNumber).
> 
> This allows the the mechanism used to retrieve the CPU maximum
> logical processor number to be abstracted from the logic that
> needs the value.
> 
> Cc: Eric Dong <eric.dong@intel.com>
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Laszlo Ersek <lersek@redhat.com>
> Cc: Rahul Kumar <rahul1.kumar@intel.com>
> Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
> ---
>  UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.c           |  2 +-
>  UefiCpuPkg/Library/SmmCpuFeaturesLib/TraditionalMmCpuFeaturesLib.c | 28 ++++++++++++++++++++
>  UefiCpuPkg/Library/SmmCpuFeaturesLib/CpuFeaturesLib.h              | 14 ++++++++++
>  UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.inf         |  1 +
>  UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLibStm.inf      |  1 +
>  5 files changed, 45 insertions(+), 1 deletion(-)
> 
> diff --git a/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.c b/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.c
> index e74f87f3f266..a494988898b8 100644
> --- a/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.c
> +++ b/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.c
> @@ -157,7 +157,7 @@ CpuFeaturesLibInitialization (
>    //
>    // Allocate array for state of SMRR enable on all CPUs
>    //
> -  mSmrrEnabled = (BOOLEAN *)AllocatePool (sizeof (BOOLEAN) * PcdGet32 (PcdCpuMaxLogicalProcessorNumber));
> +  mSmrrEnabled = (BOOLEAN *)AllocatePool (sizeof (BOOLEAN) * GetCpuMaxLogicalProcessorNumber ());
>    ASSERT (mSmrrEnabled != NULL);
>  }
>  
> diff --git a/UefiCpuPkg/Library/SmmCpuFeaturesLib/TraditionalMmCpuFeaturesLib.c b/UefiCpuPkg/Library/SmmCpuFeaturesLib/TraditionalMmCpuFeaturesLib.c
> new file mode 100644
> index 000000000000..6a4eff755d92
> --- /dev/null
> +++ b/UefiCpuPkg/Library/SmmCpuFeaturesLib/TraditionalMmCpuFeaturesLib.c
> @@ -0,0 +1,28 @@
> +/** @file
> +  Traditional MM CPU specific programming.
> +
> +  Copyright (c) Microsoft Corporation.<BR>
> +  SPDX-License-Identifier: BSD-2-Clause-Patent
> +
> +**/
> +
> +#include <Base.h>
> +#include <Library/PcdLib.h>
> +#include "CpuFeaturesLib.h"
> +
> +/**
> +  Gets the maximum number of logical processors from the PCD PcdCpuMaxLogicalProcessorNumber.
> +
> +  This access is abstracted from the PCD services to enforce that the PCD be
> +  FixedAtBuild in the Standalone MM build of this driver.
> +
> +  @retval  The value of PcdCpuMaxLogicalProcessorNumber.
> +
> +**/
> +UINT32
> +GetCpuMaxLogicalProcessorNumber (
> +  VOID
> +  )
> +{
> +  return PcdGet32 (PcdCpuMaxLogicalProcessorNumber);
> +}
> diff --git a/UefiCpuPkg/Library/SmmCpuFeaturesLib/CpuFeaturesLib.h b/UefiCpuPkg/Library/SmmCpuFeaturesLib/CpuFeaturesLib.h
> index f9a758e82558..1a72ba4e2e13 100644
> --- a/UefiCpuPkg/Library/SmmCpuFeaturesLib/CpuFeaturesLib.h
> +++ b/UefiCpuPkg/Library/SmmCpuFeaturesLib/CpuFeaturesLib.h
> @@ -31,4 +31,18 @@ FinishSmmCpuFeaturesInitializeProcessor (
>    VOID
>    );
>  
> +/**
> +  Gets the maximum number of logical processors from the PCD PcdCpuMaxLogicalProcessorNumber.
> +
> +  This access is abstracted from the PCD services to enforce that the PCD be
> +  FixedAtBuild in the Standalone MM build of this driver.
> +
> +  @retval  The value of PcdCpuMaxLogicalProcessorNumber.
> +
> +**/
> +UINT32
> +GetCpuMaxLogicalProcessorNumber (
> +  VOID
> +  );
> +
>  #endif
> diff --git a/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.inf b/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.inf
> index a6d8467d26aa..b32dbeab9383 100644
> --- a/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.inf
> +++ b/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLib.inf
> @@ -20,6 +20,7 @@ [Sources]
>    CpuFeaturesLib.h
>    SmmCpuFeaturesLib.c
>    SmmCpuFeaturesLibNoStm.c
> +  TraditionalMmCpuFeaturesLib.c
>  
>  [Packages]
>    MdePkg/MdePkg.dec
> diff --git a/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLibStm.inf b/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLibStm.inf
> index 89cd252ef44e..f72ef0a88088 100644
> --- a/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLibStm.inf
> +++ b/UefiCpuPkg/Library/SmmCpuFeaturesLib/SmmCpuFeaturesLibStm.inf
> @@ -22,6 +22,7 @@ [Sources]
>    SmmCpuFeaturesLib.c
>    SmmStm.c
>    SmmStm.h
> +  TraditionalMmCpuFeaturesLib.c
>  
>  [Sources.Ia32]
>    Ia32/SmmStmSupport.c
> 

Reviewed-by: Laszlo Ersek <lersek@redhat.com>