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;------------------------------------------------------------------------------
;
; Copyright (c) 2006 - 2008, Intel Corporation
; All rights reserved. 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:
;
; DisablePaging64.Asm
;
; Abstract:
;
; AsmDisablePaging64 function
;
; Notes:
;
;------------------------------------------------------------------------------
.code
;------------------------------------------------------------------------------
; VOID
; EFIAPI
; InternalX86DisablePaging64 (
; IN UINT16 Cs,
; IN UINT32 EntryPoint,
; IN UINT32 Context1, OPTIONAL
; IN UINT32 Context2, OPTIONAL
; IN UINT32 NewStack
; );
;------------------------------------------------------------------------------
InternalX86DisablePaging64 PROC
cli
shl rcx, 32 ; rcx[32..47] <- Cs
lea eax, @F
mov esi, r8d
or rcx, rax ; rcx[0..47] <- Cs:@F
mov edi, r9d
mov eax, [rsp + 28h] ; eax <- New Stack
push rcx
retf ; switch to compatibility mode
@@:
mov esp, eax ; set up new stack
mov rax, cr0
btr eax, 31
mov cr0, rax ; disable paging
mov rbx, rdx ; save EntryPoint to rbx, for rdmsr will overwrite rdx
mov ecx, 0c0000080h
rdmsr
and ah, NOT 1 ; clear LME
wrmsr
mov rax, cr4
and al, NOT (1 SHL 5) ; clear PAE
mov cr4, rax
push rdi ; push Context2
push rsi ; push Context1
call rbx ; transfer control to EntryPoint
hlt ; no one should get here
InternalX86DisablePaging64 ENDP
END
|
