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| author | Stefan Agner <stefan@agner.ch> | 2019-05-28 00:40:50 +0200 |
|---|---|---|
| committer | Olof Johansson <olof@lixom.net> | 2019-06-19 09:44:25 -0700 |
| commit | 3fe1ee40b2a2db271513a498c475c13572dcb4c6 (patch) | |
| tree | 64a85ad53e8d01b6443c4f1eb1146b5465dfa1c4 /arch/arm/mach-keystone | |
| parent | 24cb4bc8f0c9ee346826f33e6dcbdbc533cc6ad8 (diff) | |
| download | linux-3fe1ee40b2a2db271513a498c475c13572dcb4c6.tar.gz linux-3fe1ee40b2a2db271513a498c475c13572dcb4c6.tar.bz2 linux-3fe1ee40b2a2db271513a498c475c13572dcb4c6.zip | |
ARM: use arch_extension directive instead of arch argument
The LLVM Target parser currently does not allow to specify the security
extension as part of -march (see also LLVM Bug 40186 [0]). When trying
to use Clang with LLVM's integrated assembler, this leads to build
errors such as this:
clang-8: error: the clang compiler does not support '-Wa,-march=armv7-a+sec'
Use ".arch_extension sec" to enable the security extension in a more
portable fasion. Also make sure to use ".arch armv7-a" in case a v6/v7
multi-platform kernel is being built.
Note that this is technically not exactly the same as the old code
checked for availabilty of the security extension by calling as-instr.
However, there are already other sites which use ".arch_extension sec"
unconditionally, hence de-facto we need an assembler capable of
".arch_extension sec" already today (arch/arm/mm/proc-v7.S). The
arch extension "sec" is available since binutils 2.21 according to
its documentation [1].
[0] https://bugs.llvm.org/show_bug.cgi?id=40186
[1] https://sourceware.org/binutils/docs-2.21/as/ARM-Options.html
Signed-off-by: Stefan Agner <stefan@agner.ch>
Acked-by: Mans Rullgard <mans@mansr.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
Diffstat (limited to 'arch/arm/mach-keystone')
| -rw-r--r-- | arch/arm/mach-keystone/Makefile | 3 | ||||
| -rw-r--r-- | arch/arm/mach-keystone/smc.S | 1 |
2 files changed, 1 insertions, 3 deletions
diff --git a/arch/arm/mach-keystone/Makefile b/arch/arm/mach-keystone/Makefile index f8b0dccac8dc..739b38be5696 100644 --- a/arch/arm/mach-keystone/Makefile +++ b/arch/arm/mach-keystone/Makefile @@ -1,9 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 obj-y := keystone.o smc.o -plus_sec := $(call as-instr,.arch_extension sec,+sec) -AFLAGS_smc.o :=-Wa,-march=armv7-a$(plus_sec) - obj-$(CONFIG_SMP) += platsmp.o # PM domain driver for Keystone SOCs diff --git a/arch/arm/mach-keystone/smc.S b/arch/arm/mach-keystone/smc.S index d15de8179fab..ec03dc499270 100644 --- a/arch/arm/mach-keystone/smc.S +++ b/arch/arm/mach-keystone/smc.S @@ -21,6 +21,7 @@ * * Return: Non zero value on failure */ + .arch_extension sec ENTRY(keystone_cpu_smc) stmfd sp!, {r4-r11, lr} smc #0 |