Renesas 32-bit SH4 SoC build environment setup

In order to cross-compile U-Boot for the SH4 32-bit target, it is necessary to install a suitable toolchain. The toolchain is available in various distribution repositories as sh4-linux-gnu-* or similar package.

Debian example:

$ apt install binutils-sh4-linux-gnu cpp-sh4-linux-gnu gcc-sh4-linux-gnu

Alternatively, it is possible to download prebuilt toolchain from kernel.org cross-development toolchains page https://www.kernel.org/pub/tools/crosstool/ .

Once the toolchain is installed, add toolchain into PATH variable:

$ export PATH=$PATH:<path/to/sh4/toolchain/bin/>
$ export CROSS_COMPILE=sh4-linux-gnu-