diff options
| author | Eugeniy Paltsev | 2020-06-04 20:39:24 +0300 |
|---|---|---|
| committer | Vineet Gupta | 2020-06-16 15:07:23 -0700 |
| commit | 0bdd6e7428a2e8971d7c9b8e212056dd0e0001c9 (patch) | |
| tree | adee442762555c9ed478424427ca489a553f2507 /arch/arc | |
| parent | 97d0b5d0b5a99871a983ca9b5c02bfde8bf73cbf (diff) | |
ARC: build: allow users to specify -mcpu
kernel build system used to add -mcpu for each ARC ISA as default.
These days there are versions and varaints of ARC HS cores some of which
have specific -mcpu options to fine tune / optimize generated code.
So allow users/external build systems to specify their own -mcpu
This will be used in future patches for HSDK-4xD board support which
uses specific -mcpu to utilize dual issue scheduling of the core.
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
[abrodkin/vgupta: rewrote changelog]
Diffstat (limited to 'arch/arc')
| -rw-r--r-- | arch/arc/Kconfig | 9 | ||||
| -rw-r--r-- | arch/arc/Makefile | 21 |
2 files changed, 28 insertions, 2 deletions
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index fddc70029727..323014149e48 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -170,6 +170,15 @@ config ARC_CPU_HS endchoice +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. + config CPU_BIG_ENDIAN bool "Enable Big Endian Mode" help 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 |