Ard Biesheuvel f8b1854b92 MdePkg/BaseRngLib AARCH64: Make asm files BTI compatible
Add the BTI instructions and the associated note to make the AArch64 asm
objects compatible with BTI enforcement.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>
Reviewed-by: Oliver Smith-Denny <osd@smith-denny.com>
2023-03-30 11:05:22 +00:00

39 lines
897 B
ArmAsm

#------------------------------------------------------------------------------
#
# ArmRndr() for AArch64
#
# Copyright (c) 2021, NUVIA Inc. All rights reserved.<BR>
#
# SPDX-License-Identifier: BSD-2-Clause-Patent
#
#------------------------------------------------------------------------------
#include "BaseRngLibInternals.h"
.text
.p2align 2
GCC_ASM_EXPORT(ArmRndr)
#/**
# Generates a random number using RNDR.
# Returns TRUE on success; FALSE on failure.
#
# @param[out] Rand Buffer pointer to store the 64-bit random value.
#
# @retval TRUE Random number generated successfully.
# @retval FALSE Failed to generate the random number.
#
#**/
#BOOLEAN
#EFIAPI
#ArmRndr (
# OUT UINT64 *Rand
# );
#
ASM_PFX(ArmRndr):
AARCH64_BTI(c)
mrs x1, RNDR
str x1, [x0]
cset x0, ne // RNDR sets NZCV to 0b0100 on failure
ret