MdePkg/Library/BaseLib/Ia32/EnablePaging64.s

   1 #------------------------------------------------------------------------------
   2 #
   3 # Copyright (c) 2006, Intel Corporation
   4 # All rights reserved. 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 # Module Name:
  13 #
  14 #   EnablePaging64.Asm
  15 #
  16 # Abstract:
  17 #
  18 #   AsmEnablePaging64 function
  19 #
  20 # Notes:
  21 #
  22 #------------------------------------------------------------------------------
  23
  24
  25     #.MODEL flat
  26
  27
  28 #------------------------------------------------------------------------------
  29 # VOID
  30 # EFIAPI
  31 # AsmEnablePaging64 (
  32 #   IN      UINT16                    CodeSelector,
  33 #   IN      UINT64                    EntryPoint,
  34 #   IN      UINT64                    Context1,    OPTIONAL
  35 #   IN      UINT64                    Context2,    OPTIONAL
  36 #   IN      UINT64                    NewStack
  37 #   );
  38 #------------------------------------------------------------------------------
  39 .global _AsmEnablePaging64
  40 _AsmEnablePaging64:
  41     cli
  42     movl    $$LongStart, (%esp)
  43     movl    %cr4, %eax
  44     orb     $0x20, %al
  45     movl    %eax, %cr4                  # enable PAE
  46     movl    $0xc0000080, %ecx
  47     rdmsr
  48     orb     $1, %ah                     # set LME
  49     wrmsr
  50     movl    %cr0, %eax
  51     btsl    $31, %eax
  52     movl    %eax, %cr0                  # enable paging
  53     lret
  54 LongStart:                              # long mode starts here
  55     .byte   0x67,0x48
  56     movl    (%esp), %ebx                # mov rbx, [esp]
  57     .byte   0x67,0x48
  58     movl    8(%esp), %ecx               # mov rcx, [esp + 8]
  59     .byte   0x67,0x48
  60     movl    0x10(%esp), %edx            # mov rdx, [esp + 10h]
  61     .byte   0x67,0x48
  62     movl    0x18(%esp), %esp            # mov rsp, [esp + 18h]
  63     .byte   0x48
  64     addl    $0x-20, %esp                # add rsp, -20h
  65     call    *%ebx                       # call rbx
  66     jmp     .