From f826b20811ba6b0a9dbe44ff703b85c2def267df Mon Sep 17 00:00:00 2001
From: "Ni, Ray" <ray.ni@intel.com>
Date: Tue, 19 Oct 2021 14:42:21 +0800
Subject: [PATCH] UefiCpuPkg/UefiCpuLib: Add GetCpuFamilyModel and
 GetCpuSteppingId

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=3698

Lots of code relies on CPU Family/Model/Stepping for different logics.

The change adds two APIs for such needs.

Signed-off-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
---
 UefiCpuPkg/Include/Library/UefiCpuLib.h       | 23 +++++++++-
 .../Library/BaseUefiCpuLib/BaseUefiCpuLib.c   | 43 +++++++++++++++++++
 2 files changed, 65 insertions(+), 1 deletion(-)

diff --git a/UefiCpuPkg/Include/Library/UefiCpuLib.h b/UefiCpuPkg/Include/Library/UefiCpuLib.h
index 5326e72463..092c1d2116 100644
--- a/UefiCpuPkg/Include/Library/UefiCpuLib.h
+++ b/UefiCpuPkg/Include/Library/UefiCpuLib.h
@@ -4,7 +4,7 @@
   This library class defines some routines that are generic for IA32 family CPU
   to be UEFI specification compliant.
 
-  Copyright (c) 2009, Intel Corporation. All rights reserved.<BR>
+  Copyright (c) 2009 - 2021, Intel Corporation. All rights reserved.<BR>
   Copyright (c) 2020, AMD Inc. All rights reserved.<BR>
   SPDX-License-Identifier: BSD-2-Clause-Patent
 
@@ -43,4 +43,25 @@ StandardSignatureIsAuthenticAMD (
   VOID
   );
 
+/**
+  Return the 32bit CPU family and model value.
+
+  @return CPUID[01h].EAX with Processor Type and Stepping ID cleared.
+**/
+UINT32
+EFIAPI
+GetCpuFamilyModel (
+  VOID
+  );
+
+/**
+  Return the CPU stepping ID.
+  @return CPU stepping ID value in CPUID[01h].EAX.
+**/
+UINT8
+EFIAPI
+GetCpuSteppingId (
+  VOID
+  );
+
 #endif
diff --git a/UefiCpuPkg/Library/BaseUefiCpuLib/BaseUefiCpuLib.c b/UefiCpuPkg/Library/BaseUefiCpuLib/BaseUefiCpuLib.c
index c2cc3ff9a7..50891618c4 100644
--- a/UefiCpuPkg/Library/BaseUefiCpuLib/BaseUefiCpuLib.c
+++ b/UefiCpuPkg/Library/BaseUefiCpuLib/BaseUefiCpuLib.c
@@ -4,6 +4,7 @@
   The library routines are UEFI specification compliant.
 
   Copyright (c) 2020, AMD Inc. All rights reserved.<BR>
+  Copyright (c) 2021, Intel Corporation. All rights reserved.<BR>
   SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
@@ -36,3 +37,45 @@ StandardSignatureIsAuthenticAMD (
           RegEcx == CPUID_SIGNATURE_AUTHENTIC_AMD_ECX &&
           RegEdx == CPUID_SIGNATURE_AUTHENTIC_AMD_EDX);
 }
+
+/**
+  Return the 32bit CPU family and model value.
+
+  @return CPUID[01h].EAX with Processor Type and Stepping ID cleared.
+**/
+UINT32
+EFIAPI
+GetCpuFamilyModel (
+  VOID
+  )
+{
+  CPUID_VERSION_INFO_EAX  Eax;
+
+  AsmCpuid (CPUID_VERSION_INFO, &Eax.Uint32, NULL, NULL, NULL);
+
+  //
+  // Mask other fields than Family and Model.
+  //
+  Eax.Bits.SteppingId    = 0;
+  Eax.Bits.ProcessorType = 0;
+  Eax.Bits.Reserved1     = 0;
+  Eax.Bits.Reserved2     = 0;
+  return Eax.Uint32;
+}
+
+/**
+  Return the CPU stepping ID.
+  @return CPU stepping ID value in CPUID[01h].EAX.
+**/
+UINT8
+EFIAPI
+GetCpuSteppingId (
+  VOID
+  )
+{
+  CPUID_VERSION_INFO_EAX  Eax;
+
+  AsmCpuid (CPUID_VERSION_INFO, &Eax.Uint32, NULL, NULL, NULL);
+
+  return (UINT8) Eax.Bits.SteppingId;
+}
-- 
2.39.2