IntelFsp2WrapperPkg: Move to new location

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Guo Mang <mang.guo@intel.com>

5 files changed, 0 insertions, 669 deletions

diff --git a/IntelFsp2WrapperPkg/Library/BaseFspWrapperApiLib/BaseFspWrapperApiLib.inf b/IntelFsp2WrapperPkg/Library/BaseFspWrapperApiLib/BaseFspWrapperApiLib.inf
deleted file mode 100644
index b52cfeb284..0000000000
--- a/IntelFsp2WrapperPkg/Library/BaseFspWrapperApiLib/BaseFspWrapperApiLib.inf
+++ /dev/null
@@ -1,70 +0,0 @@
-## @file

-#  Provide FSP API related function.

-#

-#  Copyright (c) 2014 - 2016, Intel Corporation. All rights reserved.<BR>

-#

-#  This program and the accompanying materials

-#  are licensed and made available under the terms and conditions of the BSD License

-#  which accompanies this distribution. The full text of the license may be found at

-#  http://opensource.org/licenses/bsd-license.php.

-#  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,

-#  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

-#

-##

-

-################################################################################

-#

-# Defines Section - statements that will be processed to create a Makefile.

-#

-################################################################################

-[Defines]

-  INF_VERSION                    = 0x00010005

-  BASE_NAME                      = BaseFspWrapperApiLib

-  FILE_GUID                      = F42C789F-4D66-49AF-8C73-1AADC00437AC

-  MODULE_TYPE                    = BASE

-  VERSION_STRING                 = 1.0

-  LIBRARY_CLASS                  = FspWrapperApiLib

-

-#

-# The following information is for reference only and not required by the build tools.

-#

-#  VALID_ARCHITECTURES           = IA32 X64

-#

-

-################################################################################

-#

-# Sources Section - list of files that are required for the build to succeed.

-#

-################################################################################

-

-[Sources]

-  FspWrapperApiLib.c

-

-[Sources.IA32]

-  IA32/DispatchExecute.c

-

-[Sources.X64]

-  X64/DispatchExecute.c

-  X64/Thunk64To32.nasm

-

-################################################################################

-#

-# Package Dependency Section - list of Package files that are required for

-#                              this module.

-#

-################################################################################

-

-[Packages]

-  MdePkg/MdePkg.dec

-  IntelFsp2Pkg/IntelFsp2Pkg.dec

-  IntelFsp2WrapperPkg/IntelFsp2WrapperPkg.dec

-

-[LibraryClasses]

-  BaseLib

-

-[Guids]

-  gFspHeaderFileGuid            ## CONSUMES ## GUID

-

-[Pcd]

-  gIntelFsp2WrapperTokenSpaceGuid.PcdFspmBaseAddress  ## CONSUMES

-  gIntelFsp2WrapperTokenSpaceGuid.PcdFspsBaseAddress  ## CONSUMES

diff --git a/IntelFsp2WrapperPkg/Library/BaseFspWrapperApiLib/FspWrapperApiLib.c b/IntelFsp2WrapperPkg/Library/BaseFspWrapperApiLib/FspWrapperApiLib.c
deleted file mode 100644
index 38de415b27..0000000000
--- a/IntelFsp2WrapperPkg/Library/BaseFspWrapperApiLib/FspWrapperApiLib.c
+++ /dev/null
@@ -1,203 +0,0 @@
-/** @file

-  Provide FSP API related function.

-

-  Copyright (c) 2014 - 2017, Intel Corporation. All rights reserved.<BR>

-  This program and the accompanying materials

-  are licensed and made available under the terms and conditions of the BSD License

-  which accompanies this distribution.  The full text of the license may be found at

-  http://opensource.org/licenses/bsd-license.php.

-

-  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,

-  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

-

-**/

-

-#include <PiPei.h>

-

-#include <Library/FspWrapperApiLib.h>

-#include <Library/BaseLib.h>

-#include <Library/BaseMemoryLib.h>

-

-/**

-  Wrapper for a thunk  to transition from long mode to compatibility mode to execute 32-bit code and then transit back to

-  long mode.

-

-  @param[in] Function     The 32bit code entry to be executed.

-  @param[in] Param1       The first parameter to pass to 32bit code.

-  @param[in] Param2       The second parameter to pass to 32bit code.

-

-  @return EFI_STATUS.

-**/

-EFI_STATUS

-Execute32BitCode (

-  IN UINT64      Function,

-  IN UINT64      Param1,

-  IN UINT64      Param2

-  );

-

-/**

-  Find FSP header pointer.

-

-  @param[in] FlashFvFspBase Flash address of FSP FV.

-

-  @return FSP header pointer.

-**/

-FSP_INFO_HEADER *

-EFIAPI

-FspFindFspHeader (

-  IN EFI_PHYSICAL_ADDRESS  FlashFvFspBase

-  )

-{

-  UINT8 *CheckPointer;

-

-  CheckPointer = (UINT8 *) (UINTN) FlashFvFspBase;

-

-  if (((EFI_FIRMWARE_VOLUME_HEADER *)CheckPointer)->Signature != EFI_FVH_SIGNATURE) {

-    return NULL;

-  }

-

-  if (((EFI_FIRMWARE_VOLUME_HEADER *)CheckPointer)->ExtHeaderOffset != 0) {

-    CheckPointer = CheckPointer + ((EFI_FIRMWARE_VOLUME_HEADER *)CheckPointer)->ExtHeaderOffset;

-    CheckPointer = CheckPointer + ((EFI_FIRMWARE_VOLUME_EXT_HEADER *)CheckPointer)->ExtHeaderSize;

-    CheckPointer = (UINT8 *) ALIGN_POINTER (CheckPointer, 8);

-  } else {

-    CheckPointer = CheckPointer + ((EFI_FIRMWARE_VOLUME_HEADER *)CheckPointer)->HeaderLength;

-  }

-

-

-  CheckPointer = CheckPointer + sizeof (EFI_FFS_FILE_HEADER);

-

-  if (((EFI_RAW_SECTION *)CheckPointer)->Type != EFI_SECTION_RAW) {

-    return NULL;

-  }

-

-  CheckPointer = CheckPointer + sizeof (EFI_RAW_SECTION);

-

-  return (FSP_INFO_HEADER *)CheckPointer;

-}

-

-/**

-  Call FSP API - FspNotifyPhase.

-

-  @param[in] NotifyPhaseParams Address pointer to the NOTIFY_PHASE_PARAMS structure.

-

-  @return EFI status returned by FspNotifyPhase API.

-**/

-EFI_STATUS

-EFIAPI

-CallFspNotifyPhase (

-  IN NOTIFY_PHASE_PARAMS *NotifyPhaseParams

-  )

-{

-  FSP_INFO_HEADER     *FspHeader;

-  FSP_NOTIFY_PHASE    NotifyPhaseApi;

-  EFI_STATUS          Status;

-  BOOLEAN             InterruptState;

-

-  FspHeader = (FSP_INFO_HEADER *)FspFindFspHeader (PcdGet32 (PcdFspsBaseAddress));

-  if (FspHeader == NULL) {

-    return EFI_DEVICE_ERROR;

-  }

-

-  NotifyPhaseApi = (FSP_NOTIFY_PHASE)((UINTN)FspHeader->ImageBase + FspHeader->NotifyPhaseEntryOffset);

-  InterruptState = SaveAndDisableInterrupts ();

-  Status = Execute32BitCode ((UINTN)NotifyPhaseApi, (UINTN)NotifyPhaseParams, (UINTN)NULL);

-  SetInterruptState (InterruptState);

-

-  return Status;

-}

-

-/**

-  Call FSP API - FspMemoryInit.

-

-  @param[in]  FspmUpdDataPtr Address pointer to the FSP_MEMORY_INIT_PARAMS structure.

-  @param[out] HobListPtr     Address of the HobList pointer.

-

-  @return EFI status returned by FspMemoryInit API.

-**/

-EFI_STATUS

-EFIAPI

-CallFspMemoryInit (

-  IN VOID                       *FspmUpdDataPtr,

-  OUT VOID                      **HobListPtr

-  )

-{

-  FSP_INFO_HEADER     *FspHeader;

-  FSP_MEMORY_INIT     FspMemoryInitApi;

-  EFI_STATUS          Status;

-  BOOLEAN             InterruptState;

-

-  FspHeader = (FSP_INFO_HEADER *)FspFindFspHeader (PcdGet32 (PcdFspmBaseAddress));

-  if (FspHeader == NULL) {

-    return EFI_DEVICE_ERROR;

-  }

-

-  FspMemoryInitApi = (FSP_MEMORY_INIT)((UINTN)FspHeader->ImageBase + FspHeader->FspMemoryInitEntryOffset);

-  InterruptState = SaveAndDisableInterrupts ();

-  Status = Execute32BitCode ((UINTN)FspMemoryInitApi, (UINTN)FspmUpdDataPtr, (UINTN)HobListPtr);

-  SetInterruptState (InterruptState);

-

-  return Status;

-}

-

-/**

-  Call FSP API - TempRamExit.

-

-  @param[in] TempRamExitParam    Address pointer to the TempRamExit parameters structure.

-

-  @return EFI status returned by TempRamExit API.

-**/

-EFI_STATUS

-EFIAPI

-CallTempRamExit (

-  IN VOID                       *TempRamExitParam

-  )

-{

-  FSP_INFO_HEADER     *FspHeader;

-  FSP_TEMP_RAM_EXIT   TempRamExitApi;

-  EFI_STATUS          Status;

-  BOOLEAN             InterruptState;

-

-  FspHeader = (FSP_INFO_HEADER *)FspFindFspHeader (PcdGet32 (PcdFspmBaseAddress));

-  if (FspHeader == NULL) {

-    return EFI_DEVICE_ERROR;

-  }

-

-  TempRamExitApi = (FSP_TEMP_RAM_EXIT)((UINTN)FspHeader->ImageBase + FspHeader->TempRamExitEntryOffset);

-  InterruptState = SaveAndDisableInterrupts ();

-  Status = Execute32BitCode ((UINTN)TempRamExitApi, (UINTN)TempRamExitParam, (UINTN)NULL);

-  SetInterruptState (InterruptState);

-

-  return Status;

-}

-

-/**

-  Call FSP API - FspSiliconInit.

-

-  @param[in] FspsUpdDataPtr Address pointer to the Silicon Init parameters structure.

-

-  @return EFI status returned by FspSiliconInit API.

-**/

-EFI_STATUS

-EFIAPI

-CallFspSiliconInit (

-  IN VOID                       *FspsUpdDataPtr

-  )

-{

-  FSP_INFO_HEADER     *FspHeader;

-  FSP_SILICON_INIT    FspSiliconInitApi;

-  EFI_STATUS          Status;

-  BOOLEAN             InterruptState;

-

-  FspHeader = (FSP_INFO_HEADER *)FspFindFspHeader (PcdGet32 (PcdFspsBaseAddress));

-  if (FspHeader == NULL) {

-    return EFI_DEVICE_ERROR;

-  }

-

-  FspSiliconInitApi = (FSP_SILICON_INIT)((UINTN)FspHeader->ImageBase + FspHeader->FspSiliconInitEntryOffset);

-  InterruptState = SaveAndDisableInterrupts ();

-  Status = Execute32BitCode ((UINTN)FspSiliconInitApi, (UINTN)FspsUpdDataPtr, (UINTN)NULL);

-  SetInterruptState (InterruptState);

-

-  return Status;

-}

diff --git a/IntelFsp2WrapperPkg/Library/BaseFspWrapperApiLib/IA32/DispatchExecute.c b/IntelFsp2WrapperPkg/Library/BaseFspWrapperApiLib/IA32/DispatchExecute.c
deleted file mode 100644
index 72b1762f4c..0000000000
--- a/IntelFsp2WrapperPkg/Library/BaseFspWrapperApiLib/IA32/DispatchExecute.c
+++ /dev/null
@@ -1,58 +0,0 @@
-/** @file

-  Execute 32-bit code in Protected Mode.

-

-  Copyright (c) 2014 - 2016, Intel Corporation. All rights reserved.<BR>

-  This program and the accompanying materials

-  are licensed and made available under the terms and conditions of the BSD License

-  which accompanies this distribution.  The full text of the license may be found at

-  http://opensource.org/licenses/bsd-license.php.

-

-  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,

-  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

-

-**/

-

-#include <Uefi.h>

-#include <FspEas.h>

-

-/**

-  FSP API functions.

-

-  @param[in] Param1       The first parameter to pass to 32bit code.

-  @param[in] Param2       The second parameter to pass to 32bit code.

-

-  @return EFI_STATUS.

-**/

-typedef

-EFI_STATUS

-(EFIAPI *FSP_FUNCTION) (

-  IN VOID *Param1,

-  IN VOID *Param2

-  );

-

-/**

-  Wrapper for a thunk to transition from long mode to compatibility mode to execute 32-bit code and then transit back to

-  long mode.

-

-  @param[in] Function     The 32bit code entry to be executed.

-  @param[in] Param1       The first parameter to pass to 32bit code.

-  @param[in] Param2       The second parameter to pass to 32bit code.

-

-  @return EFI_STATUS.

-**/

-EFI_STATUS

-Execute32BitCode (

-  IN UINT64      Function,

-  IN UINT64      Param1,

-  IN UINT64      Param2

-  )

-{

-  FSP_FUNCTION               EntryFunc;

-  EFI_STATUS                 Status;

-

-  EntryFunc = (FSP_FUNCTION) (UINTN) (Function);

-  Status    = EntryFunc ((VOID *)(UINTN)Param1, (VOID *)(UINTN)Param2);

-

-  return Status;

-}

-

diff --git a/IntelFsp2WrapperPkg/Library/BaseFspWrapperApiLib/X64/DispatchExecute.c b/IntelFsp2WrapperPkg/Library/BaseFspWrapperApiLib/X64/DispatchExecute.c
deleted file mode 100644
index 061d381c1b..0000000000
--- a/IntelFsp2WrapperPkg/Library/BaseFspWrapperApiLib/X64/DispatchExecute.c
+++ /dev/null
@@ -1,108 +0,0 @@
-/** @file

-  Execute 32-bit code in Long Mode.

-  Provide a thunk function to transition from long mode to compatibility mode to execute 32-bit code and then transit

-  back to long mode.

-

-  Copyright (c) 2014 - 2016, Intel Corporation. All rights reserved.<BR>

-  This program and the accompanying materials

-  are licensed and made available under the terms and conditions of the BSD License

-  which accompanies this distribution.  The full text of the license may be found at

-  http://opensource.org/licenses/bsd-license.php.

-

-  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,

-  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

-

-**/

-

-#include <Uefi.h>

-#include <Library/BaseLib.h>

-#include <FspEas.h>

-

-#pragma pack(1)

-typedef union {

-  struct {

-    UINT32  LimitLow    : 16;

-    UINT32  BaseLow     : 16;

-    UINT32  BaseMid     : 8;

-    UINT32  Type        : 4;

-    UINT32  System      : 1;

-    UINT32  Dpl         : 2;

-    UINT32  Present     : 1;

-    UINT32  LimitHigh   : 4;

-    UINT32  Software    : 1;

-    UINT32  Reserved    : 1;

-    UINT32  DefaultSize : 1;

-    UINT32  Granularity : 1;

-    UINT32  BaseHigh    : 8;

-  } Bits;

-  UINT64  Uint64;

-} IA32_GDT;

-#pragma pack()

-

-GLOBAL_REMOVE_IF_UNREFERENCED IA32_GDT mGdtEntries[] = {

-  {{0,      0,  0,  0,    0,  0,  0,  0,    0,  0, 0,  0,  0}}, /* 0x0:  reserve */

-  {{0xFFFF, 0,  0,  0xB,  1,  0,  1,  0xF,  0,  0, 1,  1,  0}}, /* 0x8:  compatibility mode */

-  {{0xFFFF, 0,  0,  0xB,  1,  0,  1,  0xF,  0,  1, 0,  1,  0}}, /* 0x10: for long mode */

-  {{0xFFFF, 0,  0,  0x3,  1,  0,  1,  0xF,  0,  0, 1,  1,  0}}, /* 0x18: data */

-  {{0,      0,  0,  0,    0,  0,  0,  0,    0,  0, 0,  0,  0}}, /* 0x20: reserve */

-};

-

-//

-// IA32 Gdt register

-//

-GLOBAL_REMOVE_IF_UNREFERENCED IA32_DESCRIPTOR mGdt = {

-  sizeof (mGdtEntries) - 1,

-  (UINTN) mGdtEntries

-  };

-

-/**

-  Assembly function to transition from long mode to compatibility mode to execute 32-bit code and then transit back to

-  long mode.

-

-  @param[in] Function     The 32bit code entry to be executed.

-  @param[in] Param1       The first parameter to pass to 32bit code

-  @param[in] Param2       The second parameter to pass to 32bit code

-  @param[in] InternalGdtr The GDT and GDT descriptor used by this library

-

-  @return status.

-**/

-UINT32

-AsmExecute32BitCode (

-  IN UINT64           Function,

-  IN UINT64           Param1,

-  IN UINT64           Param2,

-  IN IA32_DESCRIPTOR  *InternalGdtr

-  );

-

-/**

-  Wrapper for a thunk  to transition from long mode to compatibility mode to execute 32-bit code and then transit back to

-  long mode.

-

-  @param[in] Function     The 32bit code entry to be executed.

-  @param[in] Param1       The first parameter to pass to 32bit code.

-  @param[in] Param2       The second parameter to pass to 32bit code.

-

-  @return EFI_STATUS.

-**/

-EFI_STATUS

-Execute32BitCode (

-  IN UINT64      Function,

-  IN UINT64      Param1,

-  IN UINT64      Param2

-  )

-{

-  EFI_STATUS       Status;

-  IA32_DESCRIPTOR  Idtr;

-

-  //

-  // Idtr might be changed inside of FSP. 32bit FSP only knows the <4G address.

-  // If IDTR.Base is >4G, FSP can not handle. So we need save/restore IDTR here for X64 only.

-  // Interrupt is already disabled here, so it is safety to update IDTR.

-  //

-  AsmReadIdtr (&Idtr);

-  Status = AsmExecute32BitCode (Function, Param1, Param2, &mGdt);

-  AsmWriteIdtr (&Idtr);

-

-  return Status;

-}

-

diff --git a/IntelFsp2WrapperPkg/Library/BaseFspWrapperApiLib/X64/Thunk64To32.nasm b/IntelFsp2WrapperPkg/Library/BaseFspWrapperApiLib/X64/Thunk64To32.nasm
deleted file mode 100644
index bcc6d70a73..0000000000
--- a/IntelFsp2WrapperPkg/Library/BaseFspWrapperApiLib/X64/Thunk64To32.nasm
+++ /dev/null
@@ -1,230 +0,0 @@
-;

-; Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>

-; This program and the accompanying materials

-; are licensed and made available under the terms and conditions of the BSD License

-; which accompanies this distribution.  The full text of the license may be found at

-; http://opensource.org/licenses/bsd-license.php.

-;

-; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,

-; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

-;

-;

-; Module Name:

-;

-;    Thunk64To32.nasm

-;

-; Abstract:

-;

-;   This is the assembly code to transition from long mode to compatibility mode to execute 32-bit code and then

-;   transit back to long mode.

-;

-;-------------------------------------------------------------------------------

-    DEFAULT REL

-    SECTION .text

-;----------------------------------------------------------------------------

-; Procedure:    AsmExecute32BitCode

-;

-; Input:        None

-;

-; Output:       None

-;

-; Prototype:    UINT32

-;               AsmExecute32BitCode (

-;                 IN UINT64           Function,

-;                 IN UINT64           Param1,

-;                 IN UINT64           Param2,

-;                 IN IA32_DESCRIPTOR  *InternalGdtr

-;                 );

-;

-;

-; Description:  A thunk function to execute 32-bit code in long mode.

-;

-;----------------------------------------------------------------------------

-global ASM_PFX(AsmExecute32BitCode)

-ASM_PFX(AsmExecute32BitCode):

-    ;

-    ; save IFLAG and disable it

-    ;

-    pushfq

-    cli

-

-    ;

-    ; save orignal GDTR and CS

-    ;

-    mov     rax, ds

-    push    rax

-    mov     rax, cs

-    push    rax

-    sub     rsp, 0x10

-    sgdt    [rsp]

-    ;

-    ; load internal GDT

-    ;

-    lgdt    [r9]

-    ;

-    ; Save general purpose register and rflag register

-    ;

-    pushfq

-    push    rdi

-    push    rsi

-    push    rbp

-    push    rbx

-

-    ;

-    ; save CR3

-    ;

-    mov     rax, cr3

-    mov     rbp, rax

-

-    ;

-    ; Prepare the CS and return address for the transition from 32-bit to 64-bit mode

-    ;

-    mov     rax, dword 0x10              ; load long mode selector

-    shl     rax, 32

-    mov     r9,  ReloadCS          ;Assume the ReloadCS is under 4G

-    or      rax, r9

-    push    rax

-    ;

-    ; Save parameters for 32-bit function call

-    ;

-    mov     rax, r8

-    shl     rax, 32

-    or      rax, rdx

-    push    rax

-    ;

-    ; save the 32-bit function entry and the return address into stack which will be

-    ; retrieve in compatibility mode.

-    ;

-    mov     rax, ReturnBack   ;Assume the ReloadCS is under 4G

-    shl     rax, 32

-    or      rax, rcx

-    push    rax

-

-    ;

-    ; let rax save DS

-    ;

-    mov     rax, dword 0x18

-

-    ;

-    ; Change to Compatible Segment

-    ;

-    mov     rcx, dword 0x8               ; load compatible mode selector

-    shl     rcx, 32

-    mov     rdx, Compatible ; assume address < 4G

-    or      rcx, rdx

-    push    rcx

-    retf

-

-Compatible:

-    ; reload DS/ES/SS to make sure they are correct referred to current GDT

-    mov     ds, ax

-    mov     es, ax

-    mov     ss, ax

-

-    ;

-    ; Disable paging

-    ;

-    mov     rcx, cr0

-    btc     ecx, 31

-    mov     cr0, rcx

-    ;

-    ; Clear EFER.LME

-    ;

-    mov     ecx, 0xC0000080

-    rdmsr

-    btc     eax, 8

-    wrmsr

-

-; Now we are in protected mode

-    ;

-    ; Call 32-bit function. Assume the function entry address and parameter value is less than 4G

-    ;

-    pop    rax                 ; Here is the function entry

-    ;

-    ; Now the parameter is at the bottom of the stack,  then call in to IA32 function.

-    ;

-    jmp   rax

-ReturnBack:

-    mov   ebx, eax             ; save return status

-    pop   rcx                  ; drop param1

-    pop   rcx                  ; drop param2

-

-    ;

-    ; restore CR4

-    ;

-    mov     rax, cr4

-    bts     eax, 5

-    mov     cr4, rax

-

-    ;

-    ; restore CR3

-    ;

-    mov     eax, ebp

-    mov     cr3, rax

-

-    ;

-    ; Set EFER.LME to re-enable ia32-e

-    ;

-    mov     ecx, 0xC0000080

-    rdmsr

-    bts     eax, 8

-    wrmsr

-    ;

-    ; Enable paging

-    ;

-    mov     rax, cr0

-    bts     eax, 31

-    mov     cr0, rax

-; Now we are in compatible mode

-

-    ;

-    ; Reload cs register

-    ;

-    retf

-ReloadCS:

-    ;

-    ; Now we're in Long Mode

-    ;

-    ;

-    ; Restore C register and eax hold the return status from 32-bit function.

-    ; Note: Do not touch rax from now which hold the return value from IA32 function

-    ;

-    mov     eax, ebx ; put return status to EAX

-    pop     rbx

-    pop     rbp

-    pop     rsi

-    pop     rdi

-    popfq

-    ;

-    ; Switch to orignal GDT and CS. here rsp is pointer to the orignal GDT descriptor.

-    ;

-    lgdt    [rsp]

-    ;

-    ; drop GDT descriptor in stack

-    ;

-    add     rsp, 0x10

-    ;

-    ; switch to orignal CS and GDTR

-    ;

-    pop     r9                 ; get  CS

-    shl     r9,  32            ; rcx[32..47] <- Cs

-    mov     rcx, .0

-    or      rcx, r9

-    push    rcx

-    retf

-.0:

-    ;

-    ; Reload original DS/ES/SS

-    ;

-    pop     rcx

-    mov     ds, rcx

-    mov     es, rcx

-    mov     ss, rcx

-

-    ;

-    ; Restore IFLAG

-    ;

-    popfq

-

-    ret

-