s390: allow to set gcc -mtune flag
Add a new Kconfig choice group which allows to configure how gcc should
tune the generated code (via -mtune option).
By default the -mtune parameter will match the -march parameter.
This is a rather large patch, but I wouldn't know how to make this shorter
unfortunately.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index a02177f..f75d7e5 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -238,6 +238,67 @@
endchoice
+config MARCH_G5_TUNE
+ def_bool TUNE_G5 || MARCH_G5 && TUNE_DEFAULT
+
+config MARCH_Z900_TUNE
+ def_bool TUNE_Z900 || MARCH_Z900 && TUNE_DEFAULT
+
+config MARCH_Z990_TUNE
+ def_bool TUNE_Z990 || MARCH_Z990 && TUNE_DEFAULT
+
+config MARCH_Z9_109_TUNE
+ def_bool TUNE_Z9_109 || MARCH_Z9_109 && TUNE_DEFAULT
+
+config MARCH_Z10_TUNE
+ def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT
+
+config MARCH_Z196_TUNE
+ def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT
+
+config MARCH_ZEC12_TUNE
+ def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT
+
+choice
+ prompt "Tune code generation"
+ default TUNE_DEFAULT
+ help
+ Cause the compiler to tune (-mtune) the generated code for a machine.
+ This will make the code run faster on the selected machine but
+ somewhat slower on other machines.
+ This option only changes how the compiler emits instructions, not the
+ selection of instructions itself, so the resulting kernel will run on
+ all other machines.
+
+config TUNE_DEFAULT
+ bool "Default"
+ help
+ Tune the generated code for the target processor for which the kernel
+ will be compiled.
+
+config TUNE_G5
+ bool "System/390 model G5 and G6"
+
+config TUNE_Z900
+ bool "IBM zSeries model z800 and z900"
+
+config TUNE_Z990
+ bool "IBM zSeries model z890 and z990"
+
+config TUNE_Z9_109
+ bool "IBM System z9"
+
+config TUNE_Z10
+ bool "IBM System z10"
+
+config TUNE_Z196
+ bool "IBM zEnterprise 114 and 196"
+
+config TUNE_ZEC12
+ bool "IBM zBC12 and zEC12"
+
+endchoice
+
config 64BIT
def_bool y
prompt "64 bit kernel"
diff --git a/arch/s390/Makefile b/arch/s390/Makefile
index ecc9d4f..874e6d6 100644
--- a/arch/s390/Makefile
+++ b/arch/s390/Makefile
@@ -43,6 +43,14 @@
cflags-$(CONFIG_MARCH_Z196) += -march=z196
cflags-$(CONFIG_MARCH_ZEC12) += -march=zEC12
+cflags-$(CONFIG_MARCH_G5_TUNE) += -mtune=g5
+cflags-$(CONFIG_MARCH_Z900_TUNE) += -mtune=z900
+cflags-$(CONFIG_MARCH_Z990_TUNE) += -mtune=z990
+cflags-$(CONFIG_MARCH_Z9_109_TUNE) += -mtune=z9-109
+cflags-$(CONFIG_MARCH_Z10_TUNE) += -mtune=z10
+cflags-$(CONFIG_MARCH_Z196_TUNE) += -mtune=z196
+cflags-$(CONFIG_MARCH_ZEC12_TUNE) += -mtune=zEC12
+
#KBUILD_IMAGE is necessary for make rpm
KBUILD_IMAGE :=arch/s390/boot/image