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authorArnd Bergmann2019-04-15 10:35:51 +0200
committerMartin Schwidefsky2019-05-03 17:17:58 +0200
commitc263a4e990b7296b074e33aa077239a0a28a818e (patch)
tree75bdcba515026deb596bbcae1c35357f3c07adba /arch
parent98587c2d894c34c9af5cd84ca169e1cd493aa692 (diff)
s390: only build for new CPUs with clang
llvm does does not understand -march=z9-109 and older target specifiers, so disable the respective Kconfig settings and the logic to make the boot code work on old systems when building with clang. Part of the early boot code is normally compiled with -march=z900 for maximum compatibility. This also has to get changed with clang to the oldest supported ISA, which is -march=z10 here. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/s390/Kconfig6
-rw-r--r--arch/s390/boot/Makefile18
2 files changed, 18 insertions, 6 deletions
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 8c15392ee985..380d13df4411 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -241,6 +241,7 @@ choice
config MARCH_Z900
bool "IBM zSeries model z800 and z900"
+ depends on !CC_IS_CLANG
select HAVE_MARCH_Z900_FEATURES
help
Select this to enable optimizations for model z800/z900 (2064 and
@@ -249,6 +250,7 @@ config MARCH_Z900
config MARCH_Z990
bool "IBM zSeries model z890 and z990"
+ depends on !CC_IS_CLANG
select HAVE_MARCH_Z990_FEATURES
help
Select this to enable optimizations for model z890/z990 (2084 and
@@ -257,6 +259,7 @@ config MARCH_Z990
config MARCH_Z9_109
bool "IBM System z9"
+ depends on !CC_IS_CLANG
select HAVE_MARCH_Z9_109_FEATURES
help
Select this to enable optimizations for IBM System z9 (2094 and
@@ -348,12 +351,15 @@ config TUNE_DEFAULT
config TUNE_Z900
bool "IBM zSeries model z800 and z900"
+ depends on !CC_IS_CLANG
config TUNE_Z990
bool "IBM zSeries model z890 and z990"
+ depends on !CC_IS_CLANG
config TUNE_Z9_109
bool "IBM System z9"
+ depends on !CC_IS_CLANG
config TUNE_Z10
bool "IBM System z10"
diff --git a/arch/s390/boot/Makefile b/arch/s390/boot/Makefile
index cb40317dc3f7..c51496bbac19 100644
--- a/arch/s390/boot/Makefile
+++ b/arch/s390/boot/Makefile
@@ -12,18 +12,24 @@ KBUILD_AFLAGS := $(KBUILD_AFLAGS_DECOMPRESSOR)
KBUILD_CFLAGS := $(KBUILD_CFLAGS_DECOMPRESSOR)
#
-# Use -march=z900 for als.c to be able to print an error
+# Use minimum architecture for als.c to be able to print an error
# message if the kernel is started on a machine which is too old
#
-ifneq ($(CC_FLAGS_MARCH),-march=z900)
+ifndef CONFIG_CC_IS_CLANG
+CC_FLAGS_MARCH_MINIMUM := -march=z900
+else
+CC_FLAGS_MARCH_MINIMUM := -march=z10
+endif
+
+ifneq ($(CC_FLAGS_MARCH),$(CC_FLAGS_MARCH_MINIMUM))
AFLAGS_REMOVE_head.o += $(CC_FLAGS_MARCH)
-AFLAGS_head.o += -march=z900
+AFLAGS_head.o += $(CC_FLAGS_MARCH_MINIMUM)
AFLAGS_REMOVE_mem.o += $(CC_FLAGS_MARCH)
-AFLAGS_mem.o += -march=z900
+AFLAGS_mem.o += $(CC_FLAGS_MARCH_MINIMUM)
CFLAGS_REMOVE_als.o += $(CC_FLAGS_MARCH)
-CFLAGS_als.o += -march=z900
+CFLAGS_als.o += $(CC_FLAGS_MARCH_MINIMUM)
CFLAGS_REMOVE_sclp_early_core.o += $(CC_FLAGS_MARCH)
-CFLAGS_sclp_early_core.o += -march=z900
+CFLAGS_sclp_early_core.o += $(CC_FLAGS_MARCH_MINIMUM)
endif
CFLAGS_sclp_early_core.o += -I$(srctree)/drivers/s390/char