mirror of https://github.com/acidanthera/audk.git
40 lines
1016 B
NASM
40 lines
1016 B
NASM
;------------------------------------------------------------------------------
|
|
; @file
|
|
; Transition from 32 bit flat protected mode into 64 bit flat protected mode
|
|
;
|
|
; Copyright (c) 2008 - 2018, Intel Corporation. All rights reserved.<BR>
|
|
; SPDX-License-Identifier: BSD-2-Clause-Patent
|
|
;
|
|
;------------------------------------------------------------------------------
|
|
|
|
BITS 32
|
|
|
|
;
|
|
; Modified: EAX
|
|
;
|
|
Transition32FlatTo64Flat:
|
|
|
|
OneTimeCall SetCr3ForPageTables64
|
|
|
|
mov eax, cr4
|
|
bts eax, 5 ; enable PAE
|
|
mov cr4, eax
|
|
|
|
mov ecx, 0xc0000080
|
|
rdmsr
|
|
bts eax, 8 ; set LME
|
|
wrmsr
|
|
|
|
mov eax, cr0
|
|
bts eax, 31 ; set PG
|
|
mov cr0, eax ; enable paging
|
|
|
|
jmp LINEAR_CODE64_SEL:ADDR_OF(jumpTo64BitAndLandHere)
|
|
BITS 64
|
|
jumpTo64BitAndLandHere:
|
|
|
|
debugShowPostCode POSTCODE_64BIT_MODE
|
|
|
|
OneTimeCallRet Transition32FlatTo64Flat
|
|
|