UefiCpuPkg/CpuDxe/X64/CpuAsm.nasm

   1 ;------------------------------------------------------------------------------
   2 ;*
   3 ;*   Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
   4 ;*   This program and the accompanying materials
   5 ;*   are licensed and made available under the terms and conditions of the BSD License
   6 ;*   which accompanies this distribution.  The full text of the license may be found at
   7 ;*   http://opensource.org/licenses/bsd-license.php
   8 ;*
   9 ;*   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 ;*   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11 ;*
  12 ;*    CpuAsm.nasm
  13 ;*
  14 ;*   Abstract:
  15 ;*
  16 ;------------------------------------------------------------------------------
  17
  18     DEFAULT REL
  19     SECTION .text
  20
  21 ;------------------------------------------------------------------------------
  22 ; VOID
  23 ; SetCodeSelector (
  24 ;   UINT16 Selector
  25 ;   );
  26 ;------------------------------------------------------------------------------
  27 global ASM_PFX(SetCodeSelector)
  28 ASM_PFX(SetCodeSelector):
  29     sub     rsp, 0x10
  30     lea     rax, [setCodeSelectorLongJump]
  31     mov     [rsp], rax
  32     mov     [rsp+4], cx
  33     jmp     dword far [rsp]
  34 setCodeSelectorLongJump:
  35     add     rsp, 0x10
  36     ret
  37
  38 ;------------------------------------------------------------------------------
  39 ; VOID
  40 ; SetDataSelectors (
  41 ;   UINT16 Selector
  42 ;   );
  43 ;------------------------------------------------------------------------------
  44 global ASM_PFX(SetDataSelectors)
  45 ASM_PFX(SetDataSelectors):
  46 o16 mov     ss, cx
  47 o16 mov     ds, cx
  48 o16 mov     es, cx
  49 o16 mov     fs, cx
  50 o16 mov     gs, cx
  51     ret
  52