scripts: added Makefile to handle an external riscv32 toolchain

Compiling Zephyr with an external riscv32 toolchain would
require the following env variables to be exported:

export ZEPHYR_GCC_VARIANT=riscv32
export RISCV32_TOOLCHAIN_PATH=/PATH/TO/TOOLCHAIN/BINARY

Change-Id: I2072ed9079a4cabd27837ab39b947bc0a0a1a8b4
Signed-off-by: Jean-Paul Etienne <fractalclone@gmail.com>
This commit is contained in:
Jean-Paul Etienne 2017-01-11 00:24:30 +01:00 committed by Andrew Boie
commit ba776a1fd1

View file

@ -0,0 +1,13 @@
ifndef RISCV32_TOOLCHAIN_PATH
$(error RISCV32_TOOLCHAIN_PATH is not set)
endif
CROSS_COMPILE = ${RISCV32_TOOLCHAIN_PATH}/bin/riscv32-unknown-elf-
TOOLCHAIN_LIBS = gcc
LIBGCC_DIR = $(shell dirname `$(CROSS_COMPILE)gcc ${KBUILD_CFLAGS} -print-libgcc-file-name`)
LIB_INCLUDE_DIR += -L ${LIBGCC_DIR}
TOOLCHAIN_CFLAGS = -I${RISCV32_TOOLCHAIN_PATH}/include
export CROSS_COMPILE TOOLCHAIN_LIBS TOOLCHAIN_CFLAGS LIB_INCLUDE_DIR