MdePkg/Library/BaseLib/X64/DisablePaging64.asm

   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 ;   DisablePaging64.Asm
  15 ;
  16 ; Abstract:
  17 ;
  18 ;   AsmDisablePaging64 function
  19 ;
  20 ; Notes:
  21 ;
  22 ;------------------------------------------------------------------------------
  23
  24     .code
  25
  26 InternalX86DisablePaging64    PROC
  27     cli
  28     shl     rcx, 32
  29     lea     ecx, @F
  30     push    rcx
  31     mov     ebx, edx
  32     mov     esi, r8d
  33     mov     edi, r9d
  34     mov     eax, [rsp + 28h]
  35     retf
  36 @@:
  37     mov     esp, eax                    ; set up new stack
  38     mov     rax, cr0
  39     btr     eax, 31
  40     mov     cr0, rax                    ; disable paging
  41     mov     ecx, 0c0000080h
  42     rdmsr
  43     and     ah, NOT 1                   ; clear LME
  44     wrmsr
  45     mov     rax, cr4
  46     and     al, NOT (1 SHL 5)           ; clear PAE
  47     mov     cr4, rax
  48     push    rdi
  49     push    rsi
  50     call    rbx
  51     jmp     $
  52 InternalX86DisablePaging64    ENDP
  53
  54     END