;------------------------------------------------------------------------------ | |
; | |
; Copyright (c) 2006 - 2012, Intel Corporation. All rights reserved.<BR> | |
; Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR> | |
; | |
; SPDX-License-Identifier: BSD-2-Clause-Patent | |
; | |
;------------------------------------------------------------------------------ | |
SECTION .text | |
;------------------------------------------------------------------------------ | |
; Check whether we need to unroll the String I/O under SEV guest | |
; | |
; Return // eax (1 - unroll, 0 - no unroll) | |
;------------------------------------------------------------------------------ | |
global ASM_PFX(SevNoRepIo) | |
ASM_PFX(SevNoRepIo): | |
; CPUID clobbers ebx, ecx and edx | |
push ebx | |
push ecx | |
push edx | |
; Check if we are running under hypervisor | |
; CPUID(1).ECX Bit 31 | |
mov eax, 1 | |
cpuid | |
bt ecx, 31 | |
jnc @UseRepIo | |
; Check if we have Memory encryption CPUID leaf | |
mov eax, 0x80000000 | |
cpuid | |
cmp eax, 0x8000001f | |
jl @UseRepIo | |
; Check for memory encryption feature: | |
; CPUID Fn8000_001F[EAX] - Bit 1 | |
; | |
mov eax, 0x8000001f | |
cpuid | |
bt eax, 1 | |
jnc @UseRepIo | |
; Check if memory encryption is enabled | |
; MSR_0xC0010131 - Bit 0 (SEV enabled) | |
; MSR_0xC0010131 - Bit 1 (SEV-ES enabled) | |
mov ecx, 0xc0010131 | |
rdmsr | |
; Check for (SevEsEnabled == 0 && SevEnabled == 1) | |
and eax, 3 | |
cmp eax, 1 | |
je @SevNoRepIo_Done | |
@UseRepIo: | |
xor eax, eax | |
@SevNoRepIo_Done: | |
pop edx | |
pop ecx | |
pop ebx | |
ret | |
;------------------------------------------------------------------------------ | |
; VOID | |
; EFIAPI | |
; IoReadFifo8 ( | |
; IN UINTN Port, | |
; IN UINTN Size, | |
; OUT VOID *Buffer | |
; ); | |
;------------------------------------------------------------------------------ | |
global ASM_PFX(IoReadFifo8) | |
ASM_PFX(IoReadFifo8): | |
push edi | |
mov dx, [esp + 8] | |
mov ecx, [esp + 12] | |
mov edi, [esp + 16] | |
; Check if we need to unroll String I/O | |
call ASM_PFX(SevNoRepIo) | |
test eax, eax | |
jnz @IoReadFifo8_NoRep | |
cld | |
rep insb | |
jmp @IoReadFifo8_Done | |
@IoReadFifo8_NoRep: | |
jecxz @IoReadFifo8_Done | |
@IoReadFifo8_Loop: | |
in al, dx | |
mov byte [edi], al | |
inc edi | |
loop @IoReadFifo8_Loop | |
@IoReadFifo8_Done: | |
pop edi | |
ret | |
;------------------------------------------------------------------------------ | |
; VOID | |
; EFIAPI | |
; IoReadFifo16 ( | |
; IN UINTN Port, | |
; IN UINTN Size, | |
; OUT VOID *Buffer | |
; ); | |
;------------------------------------------------------------------------------ | |
global ASM_PFX(IoReadFifo16) | |
ASM_PFX(IoReadFifo16): | |
push edi | |
mov dx, [esp + 8] | |
mov ecx, [esp + 12] | |
mov edi, [esp + 16] | |
; Check if we need to unroll String I/O | |
call ASM_PFX(SevNoRepIo) | |
test eax, eax | |
jnz @IoReadFifo16_NoRep | |
cld | |
rep insw | |
jmp @IoReadFifo16_Done | |
@IoReadFifo16_NoRep: | |
jecxz @IoReadFifo16_Done | |
@IoReadFifo16_Loop: | |
in ax, dx | |
mov word [edi], ax | |
add edi, 2 | |
loop @IoReadFifo16_Loop | |
@IoReadFifo16_Done: | |
pop edi | |
ret | |
;------------------------------------------------------------------------------ | |
; VOID | |
; EFIAPI | |
; IoReadFifo32 ( | |
; IN UINTN Port, | |
; IN UINTN Size, | |
; OUT VOID *Buffer | |
; ); | |
;------------------------------------------------------------------------------ | |
global ASM_PFX(IoReadFifo32) | |
ASM_PFX(IoReadFifo32): | |
push edi | |
mov dx, [esp + 8] | |
mov ecx, [esp + 12] | |
mov edi, [esp + 16] | |
; Check if we need to unroll String I/O | |
call ASM_PFX(SevNoRepIo) | |
test eax, eax | |
jnz @IoReadFifo32_NoRep | |
cld | |
rep insd | |
jmp @IoReadFifo32_Done | |
@IoReadFifo32_NoRep: | |
jecxz @IoReadFifo32_Done | |
@IoReadFifo32_Loop: | |
in eax, dx | |
mov dword [edi], eax | |
add edi, 4 | |
loop @IoReadFifo32_Loop | |
@IoReadFifo32_Done: | |
pop edi | |
ret | |
;------------------------------------------------------------------------------ | |
; VOID | |
; EFIAPI | |
; IoWriteFifo8 ( | |
; IN UINTN Port, | |
; IN UINTN Size, | |
; IN VOID *Buffer | |
; ); | |
;------------------------------------------------------------------------------ | |
global ASM_PFX(IoWriteFifo8) | |
ASM_PFX(IoWriteFifo8): | |
push esi | |
mov dx, [esp + 8] | |
mov ecx, [esp + 12] | |
mov esi, [esp + 16] | |
; Check if we need to unroll String I/O | |
call ASM_PFX(SevNoRepIo) | |
test eax, eax | |
jnz @IoWriteFifo8_NoRep | |
cld | |
rep outsb | |
jmp @IoWriteFifo8_Done | |
@IoWriteFifo8_NoRep: | |
jecxz @IoWriteFifo8_Done | |
@IoWriteFifo8_Loop: | |
mov al, byte [esi] | |
out dx, al | |
inc esi | |
loop @IoWriteFifo8_Loop | |
@IoWriteFifo8_Done: | |
pop esi | |
ret | |
;------------------------------------------------------------------------------ | |
; VOID | |
; EFIAPI | |
; IoWriteFifo16 ( | |
; IN UINTN Port, | |
; IN UINTN Size, | |
; IN VOID *Buffer | |
; ); | |
;------------------------------------------------------------------------------ | |
global ASM_PFX(IoWriteFifo16) | |
ASM_PFX(IoWriteFifo16): | |
push esi | |
mov dx, [esp + 8] | |
mov ecx, [esp + 12] | |
mov esi, [esp + 16] | |
; Check if we need to unroll String I/O | |
call ASM_PFX(SevNoRepIo) | |
test eax, eax | |
jnz @IoWriteFifo16_NoRep | |
cld | |
rep outsw | |
jmp @IoWriteFifo16_Done | |
@IoWriteFifo16_NoRep: | |
jecxz @IoWriteFifo16_Done | |
@IoWriteFifo16_Loop: | |
mov ax, word [esi] | |
out dx, ax | |
add esi, 2 | |
loop @IoWriteFifo16_Loop | |
@IoWriteFifo16_Done: | |
pop esi | |
ret | |
;------------------------------------------------------------------------------ | |
; VOID | |
; EFIAPI | |
; IoWriteFifo32 ( | |
; IN UINTN Port, | |
; IN UINTN Size, | |
; IN VOID *Buffer | |
; ); | |
;------------------------------------------------------------------------------ | |
global ASM_PFX(IoWriteFifo32) | |
ASM_PFX(IoWriteFifo32): | |
push esi | |
mov dx, [esp + 8] | |
mov ecx, [esp + 12] | |
mov esi, [esp + 16] | |
; Check if we need to unroll String I/O | |
call ASM_PFX(SevNoRepIo) | |
test eax, eax | |
jnz @IoWriteFifo32_NoRep | |
cld | |
rep outsd | |
jmp @IoWriteFifo32_Done | |
@IoWriteFifo32_NoRep: | |
jecxz @IoWriteFifo32_Done | |
@IoWriteFifo32_Loop: | |
mov eax, dword [esi] | |
out dx, eax | |
add esi, 4 | |
loop @IoWriteFifo32_Loop | |
@IoWriteFifo32_Done: | |
pop esi | |
ret | |