1.2. Building the SDK

1.2.1. Build PC setup

Please refer to the following pages from Android documentation to setup your environment for Android build:

Getting the repo tool

You will need the repo tool to retrieve repositories. To install it, please refer to this webpage : https://source.android.com/setup/develop#installing-repo

Getting toolchain for u-boot builds

Links to download toolchains for building u-boot are mentioned in the SDK download page.

Install OPTEE-OS build dependencies

Check OPTEE-OS docs to know list of dependencies needed to be installed : https://optee.readthedocs.io/en/latest/building/prerequisites.html

1.2.2. Downloading sources

Create a folder for downloading all sources

mkdir ~/09_01_00 && cd $_
export YOUR_PATH=$PWD

1.2.2.1. Bootloader components

mkdir ${YOUR_PATH}/ti-bootloader-aosp/ && cd $_
git clone -b 09.01.00.008 git://git.ti.com/atf/arm-trusted-firmware.git
git clone -b 3.22.0-rc1 https://github.com/OP-TEE/optee_os.git
git clone -b 09.01.00.008 git://git.ti.com/ti-u-boot/ti-u-boot.git
git clone -b 09.01.00.008 git://git.ti.com/processor-firmware/ti-linux-firmware.git

1.2.2.2. Kernel

Fetch the code using repo:

mkdir ${YOUR_PATH}/ti-kernel-aosp/ && cd $_
repo init -u git://git.ti.com/android/manifest.git -b android14-release -m releases/RLS_09_01_Kernel.xml
repo sync

Note

To save some disk space, pass the --depth=1 option to repo init:

repo init -u git://git.ti.com/android/manifest.git -b android14-release -m releases/RLS_09_01_Kernel.xml --depth=1

1.2.2.3. Android file system

Fetch the code using repo:

mkdir ${YOUR_PATH}/ti-aosp-14 && cd $_
repo init -u git://git.ti.com/android/manifest.git -b android14-release -m releases/RLS_09_01.xml
repo sync

1.2.3. Build Instructions

Note

The bootloader and kernel builds below are optional if they are used as-is from TI release. Prebuilt copies of these binaries are already part of Android file system sources in device/ti/am62x-kernel and vendor/ti/am62x/bootloader folder.

1.2.3.1. Bootloader components

  1. Build ATF:

    cd ${YOUR_PATH}/ti-bootloader-aosp/arm-trusted-firmware
make E=0 CROSS_COMPILE=aarch64-none-linux-gnu- ARCH=aarch64 PLAT=k3 TARGET_BOARD=lite SPD=opteed CFLAGS+="-DK3_PM_SYSTEM_SUSPEND=1"

  2. Build OPTEE-OS:

    cd ${YOUR_PATH}/ti-bootloader-aosp/optee_os
make PLATFORM=k3 CFG_ARM64_core=y CROSS_COMPILE=arm-none-linux-gnueabihf- CROSS_COMPILE64=aarch64-none-linux-gnu-

  3. Build tiboot3.bin:

cd ${YOUR_PATH}/ti-bootloader-aosp/ti-u-boot/
make ARCH=arm am62px_evm_r5_defconfig
make ARCH=arm CROSS_COMPILE=arm-none-linux-gnueabihf- \
    BINMAN_INDIRS=${YOUR_PATH}/ti-bootloader-aosp/ti-linux-firmware
  1. Build tispl.bin and u-boot.img:
cd ${YOUR_PATH}/ti-bootloader-aosp/ti-u-boot/
make ARCH=arm am62px_evm_a53_defconfig
make ARCH=arm am62x_android_a53.config
make ARCH=arm CROSS_COMPILE=aarch64-none-linux-gnu- \
    BL31=${YOUR_PATH}/ti-bootloader-aosp/arm-trusted-firmware/build/k3/lite/release/bl31.bin \
    TEE=${YOUR_PATH}/ti-bootloader-aosp/optee_os/out/arm-plat-k3/core/tee-pager_v2.bin \
    BINMAN_INDIRS=${YOUR_PATH}/ti-bootloader-aosp/ti-linux-firmware
  1. Copy the tiboot3.bin, tispl.bin and u-boot.img generated in steps 3 and 4 to ${YOUR_PATH}/ti-aosp-14/vendor/ti/am62x/bootloader. If not copied, the prebuilt bootloader binaries already present in vendor/ti/am62x/bootloader will get used by flashall.sh flashing script.

1.2.3.2. Kernel

1.2.3.2.1. Building everything from scratch

cd ${YOUR_PATH}/ti-kernel-aosp/
export DIST_DIR=${YOUR_PATH}/ti-aosp-14/device/ti/am62x-kernel/kernel/6.1
tools/bazel run //common:ti_dist -- --dist_dir=$DIST_DIR

Note

Android uses Kleaf, a Bazel-based build system to build the kernel. AOSP documentation can be found here and Kleaf documentation here

1.2.3.2.2. Rebuilding faster

cd ${YOUR_PATH}/ti-kernel-aosp/
export DIST_DIR=${YOUR_PATH}/ti-aosp-14/device/ti/am62x-kernel/kernel/6.1
tools/bazel run --config=fast //common:ti_dist -- --dist_dir=$DIST_DIR

1.2.3.2.3. Defconfig/menuconfig changes

The usual (make menuconfig ) is done via bazel command :

cd ${YOUR_PATH}/ti-kernel-aosp/
tools/bazel run //common:ti_config -- menuconfig

Note

Users must have built the android kernel image prior to building the Android file system. Otherwise pre-built kernel images present in device/ti/am62x-kernel will be used to create boot.img

1.2.3.3. Android File System

cd ${YOUR_PATH}/ti-aosp-14
source build/envsetup.sh
lunch <BUILD_TARGET>
m

Where BUILD_TARGET is listed in the table below :

Android Build type Build target
AM62PX-SK Tablet userdebug am62p-userdebug
AM62PX-SK Tablet user am62p-user
AM62PX-SK Car userdebug am62p_car-userdebug
AM62PX-SK Car user am62p_car-user

The recommended BUILD_TARGET to use is am62p-userdebug.

Note

By default with user images AVB feature is enabled. For userdebug images, if you want to enable AVB feature you need to build with TARGET_AVB_ENABLE=true build args:

cd ${YOUR_PATH}/ti-aosp-14
source build/envsetup.sh
lunch <BUILD_TARGET>
m TARGET_AVB_ENABLE=true

After building all components, refer to instruction in next section for flashing the images to EVM