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;------------------------------------------------------------------------------
;
; Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
; Module Name:
;
; EnablePaging64.Asm
;
; Abstract:
;
; AsmEnablePaging64 function
;
; Notes:
;
;------------------------------------------------------------------------------
SECTION .text
;------------------------------------------------------------------------------
; VOID
; EFIAPI
; InternalX86EnablePaging64 (
; IN UINT16 Cs,
; IN UINT64 EntryPoint,
; IN UINT64 Context1, OPTIONAL
; IN UINT64 Context2, OPTIONAL
; IN UINT64 NewStack
; );
;------------------------------------------------------------------------------
global ASM_PFX(InternalX86EnablePaging64)
ASM_PFX(InternalX86EnablePaging64):
cli
mov DWORD [esp], .0 ; offset for far retf, seg is the 1st arg
mov eax, cr4
or al, (1 << 5)
mov cr4, eax ; enable PAE
mov ecx, 0xc0000080
rdmsr
or ah, 1 ; set LME
wrmsr
mov eax, cr0
bts eax, 31 ; set PG
mov cr0, eax ; enable paging
retf ; topmost 2 dwords hold the address
.0:
BITS 64
mov rbx, [esp]
mov rcx, [esp + 8]
mov rdx, [esp + 0x10]
mov rsp, [esp + 0x18]
add rsp, -0x20
call rbx
hlt ; no one should get here
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