UefiCpuPkg/CpuDxe/X64/CpuAsm.nasm

   1 ;------------------------------------------------------------------------------
   2 ;*
   3 ;*   Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
   4 ;*   SPDX-License-Identifier: BSD-2-Clause-Patent
   5 ;*
   6 ;*    CpuAsm.nasm
   7 ;*
   8 ;*   Abstract:
   9 ;*
  10 ;------------------------------------------------------------------------------
  11
  12     DEFAULT REL
  13     SECTION .text
  14
  15 ;------------------------------------------------------------------------------
  16 ; VOID
  17 ; SetCodeSelector (
  18 ;   UINT16 Selector
  19 ;   );
  20 ;------------------------------------------------------------------------------
  21 global ASM_PFX(SetCodeSelector)
  22 ASM_PFX(SetCodeSelector):
  23     sub     rsp, 0x10
  24     lea     rax, [setCodeSelectorLongJump]
  25     mov     [rsp], rax
  26     mov     [rsp+4], cx
  27     jmp     dword far [rsp]
  28 setCodeSelectorLongJump:
  29     add     rsp, 0x10
  30     ret
  31
  32 ;------------------------------------------------------------------------------
  33 ; VOID
  34 ; SetDataSelectors (
  35 ;   UINT16 Selector
  36 ;   );
  37 ;------------------------------------------------------------------------------
  38 global ASM_PFX(SetDataSelectors)
  39 ASM_PFX(SetDataSelectors):
  40 o16 mov     ss, cx
  41 o16 mov     ds, cx
  42 o16 mov     es, cx
  43 o16 mov     fs, cx
  44 o16 mov     gs, cx
  45     ret
  46