$ sudo dpkg --add-architecture i386
$ sudo apt-get update
$ sudo apt-get install android-tools-adb android-tools-fastboot autoconf \
automake bc bison build-essential ccache codespell \
cscope curl device-tree-compiler \
expect flex ftp-upload gdisk iasl libattr1-dev libcap-dev \
libfdt-dev libftdi-dev libglib2.0-dev libgmp-dev libhidapi-dev \
libmpc-dev libncurses5-dev libpixman-1-dev libssl-dev libtool make \
mtools netcat ninja-build python3-crypto python3-pyelftools \
python3-pycryptodome python3-pyelftools python3-serial \
rsync unzip uuid-dev xdg-utils xterm xz-utils zlib1g-dev
$ mkdir -p optee-project
$ cd optee-project
$ repo init -u https://github.com/OP-TEE/manifest.git -m qemu_v8.xml
$ repo sync -j4 --no-clone-bundle
$ make toolchains
$ make run
https://trustedfirmware-a.readthedocs.io/en/latest/about/features.html