linux_dsm_epyc7002/arch/arm64/include/asm/cpucaps.h
Will Deacon d71be2b6c0 arm64: cpufeature: Detect SSBS and advertise to userspace
Armv8.5 introduces a new PSTATE bit known as Speculative Store Bypass
Safe (SSBS) which can be used as a mitigation against Spectre variant 4.

Additionally, a CPU may provide instructions to manipulate PSTATE.SSBS
directly, so that userspace can toggle the SSBS control without trapping
to the kernel.

This patch probes for the existence of SSBS and advertise the new instructions
to userspace if they exist.

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-14 17:46:01 +01:00

60 lines
2.0 KiB
C

/*
* arch/arm64/include/asm/cpucaps.h
*
* Copyright (C) 2016 ARM Ltd.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ASM_CPUCAPS_H
#define __ASM_CPUCAPS_H
#define ARM64_WORKAROUND_CLEAN_CACHE 0
#define ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE 1
#define ARM64_WORKAROUND_845719 2
#define ARM64_HAS_SYSREG_GIC_CPUIF 3
#define ARM64_HAS_PAN 4
#define ARM64_HAS_LSE_ATOMICS 5
#define ARM64_WORKAROUND_CAVIUM_23154 6
#define ARM64_WORKAROUND_834220 7
#define ARM64_HAS_NO_HW_PREFETCH 8
#define ARM64_HAS_UAO 9
#define ARM64_ALT_PAN_NOT_UAO 10
#define ARM64_HAS_VIRT_HOST_EXTN 11
#define ARM64_WORKAROUND_CAVIUM_27456 12
#define ARM64_HAS_32BIT_EL0 13
#define ARM64_HARDEN_EL2_VECTORS 14
#define ARM64_MISMATCHED_CACHE_LINE_SIZE 15
#define ARM64_HAS_NO_FPSIMD 16
#define ARM64_WORKAROUND_REPEAT_TLBI 17
#define ARM64_WORKAROUND_QCOM_FALKOR_E1003 18
#define ARM64_WORKAROUND_858921 19
#define ARM64_WORKAROUND_CAVIUM_30115 20
#define ARM64_HAS_DCPOP 21
#define ARM64_SVE 22
#define ARM64_UNMAP_KERNEL_AT_EL0 23
#define ARM64_HARDEN_BRANCH_PREDICTOR 24
#define ARM64_HAS_RAS_EXTN 25
#define ARM64_WORKAROUND_843419 26
#define ARM64_HAS_CACHE_IDC 27
#define ARM64_HAS_CACHE_DIC 28
#define ARM64_HW_DBM 29
#define ARM64_SSBD 30
#define ARM64_MISMATCHED_CACHE_TYPE 31
#define ARM64_HAS_STAGE2_FWB 32
#define ARM64_HAS_CRC32 33
#define ARM64_SSBS 34
#define ARM64_NCAPS 35
#endif /* __ASM_CPUCAPS_H */