rockchip: doc: Fix U-Boot proper location for falcon

[people/ms/u-boot.git] / doc / README.clang

diff --git a/doc/README.clang b/doc/README.clang
index 9ad689f071b2a992e7a16f059dc1bb2f4d1fe78c..e0491b2d7e6bff8e5af318870032149186118dd3 100644 (file)
--- a/doc/README.clang
+++ b/doc/README.clang
@@ -1,4 +1,4 @@
-The biggest problem when trying to compile U-boot with clang is that
+The biggest problem when trying to compile U-Boot with clang is that
 almost all archs rely on storing gd in a global register and clang user
 manual states: "clang does not support global register variables; this
 is unlikely to be implemented soon because it requires additional LLVM
@@ -17,40 +17,43 @@ will also fail to compile, but there is in no strict reason to do so
 in the ARM world, since crt0.S takes care of this. These assignments
 can be avoided by changing the init calls but this is not in mainline yet.
 
-NOTE: without the -mllvm -arm-use-movt=0 flags u-boot will compile
+NOTE: without the -mllvm -arm-use-movt=0 flags U-Boot will compile
 fine, but llvm might hardcode addresses in movw / movt pairs, which
-cannot be relocated and u-boot will fail at runtime.
+cannot be relocated and U-Boot will fail at runtime.
 
 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_b_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
+make HOSTCC=clang CC=clang -j8
 
 FreeBSD 11 (Current):
 --------------------
 Since llvm 3.4 is currently in the base system, the integrated as is
-incapable of building U-Boot. Therefore gas from devel/arm-eabi-binutils
+incapable of building U-Boot. Therefore gas from devel/arm-gnueabi-binutils
 is used instead. It needs a symlinks to be picked up correctly though:
 
-ln -s /usr/local/bin/arm-eabi-as /usr/bin/arm-freebsd-eabi-as
+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-eabi-
-gmake CC="clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd -no-integrated-as -mllvm -arm-use-movt=0" rpi_b_defconfig
-gmake CC="clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd -no-integrated-as -mllvm -arm-use-movt=0" -j8
+export CROSS_COMPILE=arm-gnueabi-freebsd-
+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
+Given that U-Boot will default to gcc, above commands can be
 simplified with a simple wrapper script, listed below.
 
-/usr/local/bin/arm-eabi-gcc
+/usr/local/bin/arm-gnueabi-freebsd-gcc
 ---
 #!/bin/sh
 
-exec clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd -no-integrated-as -mllvm -arm-use-movt=0 "$@"
-
+exec clang -target arm-freebsd-eabi --sysroot /usr/arm-freebsd "$@"