arm: clang: Update support slightly
- 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>
diff --git a/doc/README.clang b/doc/README.clang
index d41f85b..e0491b2 100644
--- a/doc/README.clang
+++ b/doc/README.clang
@@ -26,10 +26,10 @@
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 $TRIPLET -mllvm -arm-use-movt=0 -no-integrated-as" all V=1 -j8
+Note that we still use binutils for some tools so we must continue to set
+CROSS_COMPILE. To compile U-Boot with clang on linux without IAS use e.g.:
+make HOSTCC=clang rpi_2_defconfig
+make HOSTCC=clang CROSS_COMPILE=arm-linux-gnueabi- CC=clang -j8
It can also be used to compile sandbox:
make HOSTCC=clang sandbox_defconfig
@@ -46,8 +46,8 @@
# The following commands compile U-Boot using the clang xdev toolchain.
# NOTE: CROSS_COMPILE and target differ on purpose!
export CROSS_COMPILE=arm-gnueabi-freebsd-
-gmake CC="clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd -no-integrated-as -mllvm -arm-use-movt=0" rpi_defconfig
-gmake CC="clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd -no-integrated-as -mllvm -arm-use-movt=0" -j8
+gmake rpi_2_defconfig
+gmake CC="clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd" -j8
Given that U-Boot will default to gcc, above commands can be
simplified with a simple wrapper script, listed below.
@@ -56,5 +56,4 @@
---
#!/bin/sh
-exec clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd -no-integrated-as -mllvm -arm-use-movt=0 "$@"
-
+exec clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd "$@"