From 29355b4e1aed751addce6ffd85fbb65a2f409a33 Mon Sep 17 00:00:00 2001
From: "Ni, Ray" <ray.ni@intel.com>
Date: Thu, 1 Aug 2019 17:58:25 +0800
Subject: [PATCH] UefiCpuPkg/CpuDxe: Remove unnecessary macros

Today's code defines macros like CR0_PG, CR0_WP, CR4_PSE, CR4_PAE
when checking whether individual bits are set in CR0 or CR4 register.

The patch changes the code to use IA32_CR0 and IA32_CR4 structure
defined in MdePkg/Include/Library/BaseLib.h so that the module
local macros can be removed.

There is no functionality impact to this change.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Signed-off-by: Ray Ni <ray.ni@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Eric Dong <eric.dong@intel.com>
---
 UefiCpuPkg/CpuDxe/CpuPageTable.c | 43 ++++++++++++++++++--------------
 1 file changed, 24 insertions(+), 19 deletions(-)

diff --git a/UefiCpuPkg/CpuDxe/CpuPageTable.c b/UefiCpuPkg/CpuDxe/CpuPageTable.c
index c369b44f12..16a2528b55 100644
--- a/UefiCpuPkg/CpuDxe/CpuPageTable.c
+++ b/UefiCpuPkg/CpuDxe/CpuPageTable.c
@@ -1,7 +1,7 @@
 /** @file
   Page table management support.
 
-  Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
+  Copyright (c) 2017 - 2019, Intel Corporation. All rights reserved.<BR>
   Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR>
 
   SPDX-License-Identifier: BSD-2-Clause-Patent
@@ -21,14 +21,6 @@
 #include "CpuDxe.h"
 #include "CpuPageTable.h"
 
-///
-/// Paging registers
-///
-#define CR0_WP                      BIT16
-#define CR0_PG                      BIT31
-#define CR4_PSE                     BIT4
-#define CR4_PAE                     BIT5
-
 ///
 /// Page Table Entry
 ///
@@ -161,6 +153,8 @@ GetCurrentPagingContext (
   UINT32                          RegEax;
   CPUID_EXTENDED_CPU_SIG_EDX      RegEdx;
   MSR_IA32_EFER_REGISTER          MsrEfer;
+  IA32_CR4                        Cr4;
+  IA32_CR0                        Cr0;
 
   //
   // Don't retrieve current paging context from processor if in SMM mode.
@@ -172,21 +166,24 @@ GetCurrentPagingContext (
     } else {
       mPagingContext.MachineType = IMAGE_FILE_MACHINE_I386;
     }
-    if ((AsmReadCr0 () & CR0_PG) != 0) {
+
+    Cr0.UintN = AsmReadCr0 ();
+    Cr4.UintN = AsmReadCr4 ();
+
+    if (Cr0.Bits.PG != 0) {
       mPagingContext.ContextData.X64.PageTableBase = (AsmReadCr3 () & PAGING_4K_ADDRESS_MASK_64);
     } else {
       mPagingContext.ContextData.X64.PageTableBase = 0;
     }
-
-    if ((AsmReadCr4 () & CR4_PSE) != 0) {
+    if (Cr0.Bits.WP  != 0) {
+      mPagingContext.ContextData.Ia32.Attributes |= PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_WP_ENABLE;
+    }
+    if (Cr4.Bits.PSE != 0) {
       mPagingContext.ContextData.Ia32.Attributes |= PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_PSE;
     }
-    if ((AsmReadCr4 () & CR4_PAE) != 0) {
+    if (Cr4.Bits.PAE != 0) {
       mPagingContext.ContextData.Ia32.Attributes |= PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_PAE;
     }
-    if ((AsmReadCr0 () & CR0_WP) != 0) {
-      mPagingContext.ContextData.Ia32.Attributes |= PAGE_TABLE_LIB_PAGING_CONTEXT_IA32_X64_ATTRIBUTES_WP_ENABLE;
-    }
 
     AsmCpuid (CPUID_EXTENDED_FUNCTION, &RegEax, NULL, NULL, NULL);
     if (RegEax >= CPUID_EXTENDED_CPU_SIG) {
@@ -581,12 +578,14 @@ IsReadOnlyPageWriteProtected (
   VOID
   )
 {
+  IA32_CR0  Cr0;
   //
   // To avoid unforseen consequences, don't touch paging settings in SMM mode
   // in this driver.
   //
   if (!IsInSmm ()) {
-    return ((AsmReadCr0 () & CR0_WP) != 0);
+    Cr0.UintN = AsmReadCr0 ();
+    return (BOOLEAN) (Cr0.Bits.WP != 0);
   }
   return FALSE;
 }
@@ -599,12 +598,15 @@ DisableReadOnlyPageWriteProtect (
   VOID
   )
 {
+  IA32_CR0  Cr0;
   //
   // To avoid unforseen consequences, don't touch paging settings in SMM mode
   // in this driver.
   //
   if (!IsInSmm ()) {
-    AsmWriteCr0 (AsmReadCr0 () & ~CR0_WP);
+    Cr0.UintN = AsmReadCr0 ();
+    Cr0.Bits.WP = 0;
+    AsmWriteCr0 (Cr0.UintN);
   }
 }
 
@@ -616,12 +618,15 @@ EnableReadOnlyPageWriteProtect (
   VOID
   )
 {
+  IA32_CR0  Cr0;
   //
   // To avoid unforseen consequences, don't touch paging settings in SMM mode
   // in this driver.
   //
   if (!IsInSmm ()) {
-    AsmWriteCr0 (AsmReadCr0 () | CR0_WP);
+    Cr0.UintN = AsmReadCr0 ();
+    Cr0.Bits.WP = 1;
+    AsmWriteCr0 (Cr0.UintN);
   }
 }
 
-- 
2.39.2