- Move most of the flags required into LLVM_RELFLAGS to test at build time instead of requiring them to be passed in. - Update doc/README.clang to reflect this - Switch to rpi_2 as the example as it's closer to working out of the box than rpi is.

Cc: Jeroen Hofstee jeroen@myspectrum.nl Signed-off-by: Tom Rini trini@konsulko.com --- arch/arm/Makefile | 3 ++- arch/arm/config.mk | 6 ++++++ doc/README.clang | 15 +++++++-------- 3 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/arch/arm/Makefile b/arch/arm/Makefile index 6defdfb..797f00c 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -16,7 +16,8 @@ arch-$(CONFIG_CPU_SA1100) =-march=armv4 arch-$(CONFIG_CPU_PXA) = arch-$(CONFIG_CPU_ARM1136) =-march=armv5 arch-$(CONFIG_CPU_ARM1176) =-march=armv5t -arch-$(CONFIG_CPU_V7) =$(call cc-option, -march=armv7-a, -march=armv5) +arch-$(CONFIG_CPU_V7) =$(call cc-option, -march=armv7-a, \ + $(call cc-option, -march=armv7, -march=armv5)) arch-$(CONFIG_ARM64) =-march=armv8-a

# Evaluate arch cc-option calls now diff --git a/arch/arm/config.mk b/arch/arm/config.mk index 9af6c37..9a5a974 100644 --- a/arch/arm/config.mk +++ b/arch/arm/config.mk @@ -19,6 +19,12 @@ PLATFORM_RELFLAGS += -ffunction-sections -fdata-sections \ PLATFORM_RELFLAGS += $(call cc-option, -msoft-float) \ $(call cc-option,-mshort-load-bytes,$(call cc-option,-malignment-traps,))

+# LLVM support +LLVMS_RELFLAGS := $(call cc-option,-mllvm,) \ + $(call cc-option,-target arm-none-eabi,) \ + $(call cc-option,-arm-use-movt=0,) +PLATFORM_RELFLAGS += $(LLVM_RELFLAGS) + PLATFORM_CPPFLAGS += -D__ARM__

# Choose between ARM/Thumb instruction sets diff --git a/doc/README.clang b/doc/README.clang index 7ce5ae4..b4ba653 100644 --- a/doc/README.clang +++ b/doc/README.clang @@ -26,10 +26,10 @@ Debian (based) Binary packages can be installed as usual, e.g.: sudo apt-get install clang

-To compile U-Boot with clang on linux without IAS use e.g.: -export TRIPLET=arm-linux-gnueabi && export CROSS_COMPILE="$TRIPLET-" -make HOSTCC=clang CC="clang -target $TRIPLET -mllvm -arm-use-movt=0 -no-integrated-as" rpi_defconfig -make HOSTCC=clang CC="clang -target $TRIPLET -mllvm -arm-use-movt=0 -no-integrated-as" all V=1 -j8 +Note that we still use binutils for some tools so we must continue to set +CROSS_COMPILE. To compile U-Boot with clang on linux without IAS use e.g.: +make HOSTCC=clang rpi_2_defconfig +make HOSTCC=clang CROSS_COMPILE=arm-linux-gnueabi- CC=clang -j8

FreeBSD 11 (Current): -------------------- @@ -42,8 +42,8 @@ ln -s /usr/local/bin/arm-gnueabi-freebsd-as /usr/bin/arm-freebsd-eabi-as # The following commands compile U-Boot using the clang xdev toolchain. # NOTE: CROSS_COMPILE and target differ on purpose! export CROSS_COMPILE=arm-gnueabi-freebsd- -gmake CC="clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd -no-integrated-as -mllvm -arm-use-movt=0" rpi_defconfig -gmake CC="clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd -no-integrated-as -mllvm -arm-use-movt=0" -j8 +gmake rpi_2_defconfig +gmake CC="clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd" -j8

Given that U-Boot will default to gcc, above commands can be simplified with a simple wrapper script, listed below. @@ -52,5 +52,4 @@ simplified with a simple wrapper script, listed below. --- #!/bin/sh

-exec clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd -no-integrated-as -mllvm -arm-use-movt=0 "$@" - +exec clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd "$@"