Kernel builds set their own default -mcpu for a given ISA build. But that gets in the way of "custom" -mcpu flags from propagating into kernel build. This will also be used in next patches for HSDK-4xD board support which uses a different -mcpu to effect dual issue scheduling. Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx> --- arch/arc/Kconfig | 9 +++++++++ arch/arc/Makefile | 21 +++++++++++++++++++-- 2 files changed, 28 insertions(+), 2 deletions(-) diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index ff306246d0f8..7034c217708f 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -377,6 +377,15 @@ config ARC_HAS_SWAPE bool "Insn: SWAPE (endian-swap)" default y +config ARC_TUNE_MCPU + string "Override default -mcpu compiler flag" + default "" + help + Override default -mcpu=xxx compiler flag (which is set depending on + the ISA version) with the specified value. + NOTE: If specified flag isn't supported by current compiler the + ISA default value will be used as a fallback. + if ISA_ARCV2 config ARC_USE_UNALIGNED_MEM_ACCESS diff --git a/arch/arc/Makefile b/arch/arc/Makefile index 20e9ab6cc521..2b66e8264174 100644 --- a/arch/arc/Makefile +++ b/arch/arc/Makefile @@ -10,8 +10,25 @@ CROSS_COMPILE := $(call cc-cross-prefix, arc-linux- arceb-linux-) endif cflags-y += -fno-common -pipe -fno-builtin -mmedium-calls -D__linux__ -cflags-$(CONFIG_ISA_ARCOMPACT) += -mA7 -cflags-$(CONFIG_ISA_ARCV2) += -mcpu=hs38 + +tune-mcpu-def-$(CONFIG_ISA_ARCOMPACT) := -mA7 +tune-mcpu-def-$(CONFIG_ISA_ARCV2) := -mcpu=hs38 + +ifeq ($(CONFIG_ARC_TUNE_MCPU),"") +cflags-y += $(tune-mcpu-def-y) +else +tune-mcpu := $(shell echo $(CONFIG_ARC_TUNE_MCPU)) +tune-mcpu-ok := $(call cc-option-yn, $(tune-mcpu)) +ifeq ($(tune-mcpu-ok),y) +cflags-y += $(tune-mcpu) +else +# The flag provided by 'CONFIG_ARC_TUNE_MCPU' option isn't known by this compiler +# (probably the compiler is too old). Use ISA default mcpu flag instead as a safe option. +$(warning ** WARNING ** CONFIG_ARC_TUNE_MCPU flag '$(tune-mcpu)' is unknown, fallback to '$(tune-mcpu-def-y)') +cflags-y += $(tune-mcpu-def-y) +endif +endif + ifdef CONFIG_ARC_CURR_IN_REG # For a global register defintion, make sure it gets passed to every file -- 2.21.3 _______________________________________________ linux-snps-arc mailing list linux-snps-arc@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/linux-snps-arc
