BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2198 Under SEV-ES, a CPUID instruction requires the current value of the XCR0 register. In order to retrieve that value, the XGETBV instruction needs to be executed. Provide the necessary support to execute the XGETBV instruction. Cc: Michael D Kinney <michael.d.kinney@intel.com> Cc: Liming Gao <liming.gao@intel.com> Reviewed-by: Liming Gao <liming.gao@intel.com> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Regression-tested-by: Laszlo Ersek <lersek@redhat.com>
35 lines
768 B
NASM
35 lines
768 B
NASM
;------------------------------------------------------------------------------
|
|
;
|
|
; Copyright (C) 2020, Advanced Micro Devices, Inc. All rights reserved.<BR>
|
|
; SPDX-License-Identifier: BSD-2-Clause-Patent
|
|
;
|
|
; Module Name:
|
|
;
|
|
; XGetBv.Asm
|
|
;
|
|
; Abstract:
|
|
;
|
|
; AsmXgetBv function
|
|
;
|
|
; Notes:
|
|
;
|
|
;------------------------------------------------------------------------------
|
|
|
|
DEFAULT REL
|
|
SECTION .text
|
|
|
|
;------------------------------------------------------------------------------
|
|
; UINT64
|
|
; EFIAPI
|
|
; AsmXGetBv (
|
|
; IN UINT32 Index
|
|
; );
|
|
;------------------------------------------------------------------------------
|
|
global ASM_PFX(AsmXGetBv)
|
|
ASM_PFX(AsmXGetBv):
|
|
xgetbv
|
|
shl rdx, 32
|
|
or rax, rdx
|
|
ret
|
|
|