[Patch v3 1/5] UefiCpuPkg/PiSmmCpuDxeSmm: Use GDT/IDT saved in Smram.

[Eric Dong <eric.dong@intel.com>]

Current implementation copies GDT/IDT at SmmReadyToLock point
from ACPI NVS memory to Smram. Later at S3 resume phase, it restores
memory saved in Smram to ACPI NVS. Driver can directly use GDT/IDT
saved in Smram instead of restore the original ACPI NVS memory.

This patch do this change.

Test Done:
  Do the OS boot and S3 resume test.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
---
 UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c b/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c
index 0b8ef70359..764d8276d3 100644
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/CpuS3.c
@@ -448,13 +448,6 @@ PrepareApStartupVector (
   CopyMem ((VOID *) (UINTN) &mExchangeInfo->GdtrProfile, (VOID *) (UINTN) mAcpiCpuData.GdtrProfile, sizeof (IA32_DESCRIPTOR));
   CopyMem ((VOID *) (UINTN) &mExchangeInfo->IdtrProfile, (VOID *) (UINTN) mAcpiCpuData.IdtrProfile, sizeof (IA32_DESCRIPTOR));
 
-  //
-  // Copy AP's GDT, IDT and Machine Check handler from SMRAM to ACPI NVS memory
-  //
-  CopyMem ((VOID *) mExchangeInfo->GdtrProfile.Base, mGdtForAp, mExchangeInfo->GdtrProfile.Limit + 1);
-  CopyMem ((VOID *) mExchangeInfo->IdtrProfile.Base, mIdtForAp, mExchangeInfo->IdtrProfile.Limit + 1);
-  CopyMem ((VOID *)(UINTN) mAcpiCpuData.ApMachineCheckHandlerBase, mMachineCheckHandlerForAp, mAcpiCpuData.ApMachineCheckHandlerSize);
-
   mExchangeInfo->StackStart  = (VOID *) (UINTN) mAcpiCpuData.StackAddress;
   mExchangeInfo->StackSize   = mAcpiCpuData.StackSize;
   mExchangeInfo->BufferStart = (UINT32) StartupVector;
@@ -901,6 +894,10 @@ GetAcpiCpuData (
   CopyMem (mGdtForAp, (VOID *)Gdtr->Base, Gdtr->Limit + 1);
   CopyMem (mIdtForAp, (VOID *)Idtr->Base, Idtr->Limit + 1);
   CopyMem (mMachineCheckHandlerForAp, (VOID *)(UINTN)mAcpiCpuData.ApMachineCheckHandlerBase, mAcpiCpuData.ApMachineCheckHandlerSize);
+
+  Gdtr->Base = (UINTN)mGdtForAp;
+  Idtr->Base = (UINTN)mIdtForAp;
+  mAcpiCpuData.ApMachineCheckHandlerBase = (EFI_PHYSICAL_ADDRESS)(UINTN)mMachineCheckHandlerForAp;
 }
 
 /**
-- 
2.15.0.windows.1