diff options
author | Paul Burton <paul.burton@mips.com> | 2019-10-10 18:54:03 +0000 |
---|---|---|
committer | Paul Burton <paul.burton@mips.com> | 2019-10-10 11:58:52 -0700 |
commit | 2f2b4fd674cadd8c6b40eb629e140a14db4068fd (patch) | |
tree | e023cae4f998b44251f058415364b0b1ff890c0f | |
parent | 38dffe1e4dde1d3174fdce09d67370412843ebb5 (diff) |
MIPS: Disable Loongson MMI instructions for kernel build
GCC 9.x automatically enables support for Loongson MMI instructions when
using some -march= flags, and then errors out when -msoft-float is
specified with:
cc1: error: ‘-mloongson-mmi’ must be used with ‘-mhard-float’
The kernel shouldn't be using these MMI instructions anyway, just as it
doesn't use floating point instructions. Explicitly disable them in
order to fix the build with GCC 9.x.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Fixes: 3702bba5eb4f ("MIPS: Loongson: Add GCC 4.4 support for Loongson2E")
Fixes: 6f7a251a259e ("MIPS: Loongson: Add basic Loongson 2F support")
Fixes: 5188129b8c9f ("MIPS: Loongson-3: Improve -march option and move it to Platform")
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: stable@vger.kernel.org # v2.6.32+
Cc: linux-mips@vger.kernel.org
-rw-r--r-- | arch/mips/loongson64/Platform | 4 | ||||
-rw-r--r-- | arch/mips/vdso/Makefile | 1 |
2 files changed, 5 insertions, 0 deletions
diff --git a/arch/mips/loongson64/Platform b/arch/mips/loongson64/Platform index c1a4d4dc4665..9f79908f5063 100644 --- a/arch/mips/loongson64/Platform +++ b/arch/mips/loongson64/Platform @@ -66,6 +66,10 @@ else $(call cc-option,-march=mips64r2,-mips64r2 -U_MIPS_ISA -D_MIPS_ISA=_MIPS_ISA_MIPS64) endif +# Some -march= flags enable MMI instructions, and GCC complains about that +# support being enabled alongside -msoft-float. Thus explicitly disable MMI. +cflags-y += $(call cc-option,-mno-loongson-mmi) + # # Loongson Machines' Support # diff --git a/arch/mips/vdso/Makefile b/arch/mips/vdso/Makefile index 807f0f782f75..996a934ece7d 100644 --- a/arch/mips/vdso/Makefile +++ b/arch/mips/vdso/Makefile @@ -15,6 +15,7 @@ ccflags-vdso := \ $(filter -mmicromips,$(KBUILD_CFLAGS)) \ $(filter -march=%,$(KBUILD_CFLAGS)) \ $(filter -m%-float,$(KBUILD_CFLAGS)) \ + $(filter -mno-loongson-%,$(KBUILD_CFLAGS)) \ -D__VDSO__ ifdef CONFIG_CC_IS_CLANG |