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;------------------------------------------------------------------------------ ;
; Copyright (c) 2016 - 2018, Intel Corporation. All rights reserved.<BR>
; 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:
;
; SmmInit.nasm
;
; Abstract:
;
; Functions for relocating SMBASE's for all processors
;
;-------------------------------------------------------------------------------
extern ASM_PFX(SmmInitHandler)
extern ASM_PFX(mRebasedFlag)
extern ASM_PFX(mSmmRelocationOriginalAddress)
global ASM_PFX(gPatchSmmCr3)
global ASM_PFX(gPatchSmmCr4)
global ASM_PFX(gSmmCr0)
global ASM_PFX(gSmmJmpAddr)
global ASM_PFX(gSmmInitStack)
global ASM_PFX(gcSmiInitGdtr)
global ASM_PFX(gcSmmInitSize)
global ASM_PFX(gcSmmInitTemplate)
%define PROTECT_MODE_CS 0x8
%define PROTECT_MODE_DS 0x20
SECTION .text
ASM_PFX(gcSmiInitGdtr):
DW 0
DQ 0
global ASM_PFX(SmmStartup)
BITS 16
ASM_PFX(SmmStartup):
mov eax, 0x80000001 ; read capability
cpuid
mov ebx, edx ; rdmsr will change edx. keep it in ebx.
and ebx, BIT20 ; extract NX capability bit
shr ebx, 9 ; shift bit to IA32_EFER.NXE[BIT11] position
mov eax, strict dword 0 ; source operand will be patched
ASM_PFX(gPatchSmmCr3):
mov cr3, eax
o32 lgdt [cs:ebp + (ASM_PFX(gcSmiInitGdtr) - ASM_PFX(SmmStartup))]
mov eax, strict dword 0 ; source operand will be patched
ASM_PFX(gPatchSmmCr4):
mov cr4, eax
mov ecx, 0xc0000080 ; IA32_EFER MSR
rdmsr
or eax, ebx ; set NXE bit if NX is available
wrmsr
DB 0x66, 0xb8 ; mov eax, imm32
ASM_PFX(gSmmCr0): DD 0
mov di, PROTECT_MODE_DS
mov cr0, eax
DB 0x66, 0xea ; jmp far [ptr48]
ASM_PFX(gSmmJmpAddr):
DD @32bit
DW PROTECT_MODE_CS
BITS 32
@32bit:
mov ds, edi
mov es, edi
mov fs, edi
mov gs, edi
mov ss, edi
DB 0xbc ; mov esp, imm32
ASM_PFX(gSmmInitStack): DD 0
call ASM_PFX(SmmInitHandler)
rsm
BITS 16
ASM_PFX(gcSmmInitTemplate):
mov ebp, ASM_PFX(SmmStartup)
sub ebp, 0x30000
jmp ebp
ASM_PFX(gcSmmInitSize): DW $ - ASM_PFX(gcSmmInitTemplate)
BITS 32
global ASM_PFX(SmmRelocationSemaphoreComplete)
ASM_PFX(SmmRelocationSemaphoreComplete):
push eax
mov eax, [ASM_PFX(mRebasedFlag)]
mov byte [eax], 1
pop eax
jmp [ASM_PFX(mSmmRelocationOriginalAddress)]
global ASM_PFX(PiSmmCpuSmmInitFixupAddress)
ASM_PFX(PiSmmCpuSmmInitFixupAddress):
ret
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