1.3. Building the SDK¶

1.3.1. Using the Prebuilt Release Images¶

The prebuilt release image can be found in the ‘board-support/prebuilt-images/’ directory of the Processor SDK Android installation.

Follow the create-sdcard.sh script (found in the ‘bin/’ directory of the SDK) to create a bootable SD card. Then, use the top-level setup.sh script to flash the prebuilt release images to the eMMC of your EVM or IDK.

Note

Booting Android solely from the SD card is not supported starting from the Processor SDK Android v4.2 release. The SD card is used to run U-Boot in order to flash the onboard eMMC.

Note

For AM572x EVM, the flashing procedure will put u-boot into the eMMC for subsequent boots, and therefore, SD card is required for the first boot only. For AM57xx IDK, u-boot is not flashed, and the SD card (with the boot files) is required always.

1.3.2. Rebuilding Android from Sources¶

Follow the steps below to rebuild Android from sources when there is a need to do so, e.g., after modifications are made for the sources.

1.3.2.1. Build PC setup¶

You need a 64-bit Ubuntu machine (Version Supported) for building the Android file system.

Install Pre-requisite packages for building the Android File System

Follow instructions from official Android page here for setting up the packages required for building Android.

Use the following command to install the same packages that were used during the SDK development process:

sudo apt-get install git-core gnupg flex bison gperf build-essential zip curl zlib1g-dev gcc-multilib g++-multilib libc6-dev-i386 lib32ncurses5-dev x11proto-core-dev libx11-dev lib32z-dev ccache libgl1-mesa-dev libxml2-utils xsltproc unzip lzop bc u-boot-tools libssl-dev

Proxy/Firewall

If you are behind proxy/firewall, workaround it using the instructions in Host PC Setup. For installing repo make sure you also export https_proxy environment variable.

repo Tool

Google’s repo tool is used to clone all of the git repositories that you need to rebuild the full Android filesystem from source. A copy of the repo tool is provided in the Processor SDK Android in the board-support/aosp-<ver>/.repo/repo/ directory. Instructions to use the repo tool are provided below in this guide.

Tool Chain for building Kernel and Drivers

The Kernel and Driver sources are built using the Android linux-x86 toolchain for ARM GNU/Linux version . This tool chain is provided in the android-devkit directory of the SDK.

1.3.2.2. U-Boot, Linux Kernel, and Android Filesystem Sources¶

Android Filesystem Sources

You can get the Android filesystem sources for this release by using the repo tool along with the provided manifest file.

cd ~/ti-processor-sdk-android-<platform>-<ver>/board-support/aosp-<ver>/
./repo sync

If it is desired to pull in changes and fixes made after the release, please run ”./repo init” prior to ”./repo sync”.

cd ~/ti-processor-sdk-android-<platform>-<ver>/board-support/aosp-<ver>/
./repo init
./repo sync

This command may take several hours as it is cloning hundreds of repositories and checking them out to a specific commit. This will also take up considerable space on your development machine’s hard drive (~70GB).

Note

The repo tool has already been initialized with the manifest file found in board-support/aosp-<ver>/.repo/manifest.xml. That is why only the ‘repo sync’ command is required above.

TI Hardware Accelerated Graphics Binaries

Accelerated graphics binaries are part of Android file system build.

U-Boot Sources

The U-Boot sources are included in the Processor Android SDK in the board-support/u-boot-<ver>/ directory.

Kernel & Driver Sources

The Linux kernel sources are included in the Processor Android SDK in the board-support/linux-<ver>/ directory.

1.3.2.3. Build Instructions¶

1.3.2.3.1. Building U-boot sources¶

The top-level Makefile can be used to build MLO and U-Boot

cd ~/ti-processor-sdk-android-<platform>-<ver>/
make u-boot

1.3.2.3.2. Building Kernel¶

The top-level Makefile can also be used to build the Linux kernel

cd ~/ti-processor-sdk-android-<platform>-<ver>/
make linux
make linux-dtbs

1.3.2.3.3. Building Android Filesystem (AFS)¶

Note

Users must have built the android kernel image prior to building the Android file system.

Instructions for building Android file system for AM5:

cd ~/ti-processor-sdk-android-am57xx-evm-<ver>/board-support/aosp-<ver>/
export KERNELDIR=~/ti-processor-sdk-android-am57xx-evm-<ver>/board-support/linux-<ver>/
make -j8 clean
. build/envsetup.sh
lunch am57xevm_full-userdebug
make -j8

Instructions for building Android file system for AM6:

cd ~/ti-processor-sdk-android-am65xx-evm-<ver>/board-support/aosp-<ver>/
export KERNELDIR=~/ti-processor-sdk-android-am65xx-evm-<ver>/board-support/linux-<ver>/
make -j8 clean
. build/envsetup.sh
lunch am65xevm_full-userdebug
make -j8

See Android Build Tricks for tricks on building Android. Adjust -jX to match your build machine, where X is the number of jobs.

1.3.2.4. Preparing Android Image¶

This step is to rebuild Android Filesystem (AFS) to include kernel, making your kernel to be part of boot.img

Copy Kernel Image:

cd ~/ti-processor-sdk-android-<platform>-<ver>/board-support/aosp-<ver>
cp -v ../linux-<ver>/arch/arm/boot/zImage device/ti/<platform>/kernel

Rebuild AFS to generate update images for AM5:

cd ~/ti-processor-sdk-android-am57xx-evm-<ver>/board-support/aosp-<ver>/
. build/envsetup.sh
lunch am57xevm_full-userdebug
rm out/target/product/am57xevm/*.img
rm out/target/product/am57xevm/obj/PACKAGING/systemimage_intermediates/system.img
make -j2

Rebuild AFS to generate update images for AM6:

cd ~/ti-processor-sdk-android-am65xx-evm-<ver>/board-support/aosp-<ver>/
. build/envsetup.sh
lunch am65xevm_full-userdebug
rm out/target/product/am65xevm/*.img
rm out/target/product/am65xevm/obj/PACKAGING/systemimage_intermediates/system.img
make -j2

1.3.3. Flashing eMMC images¶

1.3.3.1. Preparing eMMC binaries/images¶

Make a copy of the prebuilt-images directory, and then copy over the rebuilt files to the prebuilt-images directory.

AM5:

cd ~/ti-processor-sdk-android-am57xx-evm-<ver>/board-support/
cp -r prebuilt-images prebuilt-images-psdk
cp -v ./aosp-<ver>/out/target/product/am57xevm/*img prebuilt-images
cp -v ./aosp-<ver>/device/ti/am57xevm/fastboot.sh prebuilt-images
cp -v ./aosp-<ver>/out/host/linux-x86/bin/{simg2img,mkbootimg,fastboot,adb} prebuilt-images
cp -v ./linux-<ver>/arch/arm/boot/zImage prebuilt-images/zImage-am57xx-evm.bin
cp -v ./linux-<ver>/arch/arm/boot/dts/am57*.dtb prebuilt-images
cp -v ./u-boot-<ver>/MLO prebuilt-images
cp -v ./u-boot-<ver>/u-boot.img prebuilt-images

AM6:

cd ~/ti-processor-sdk-android-am65xx-evm-<ver>/board-support/
cp -r prebuilt-images prebuilt-images-psdk
cp -v ./aosp-<ver>/out/target/product/am65xevm/*img prebuilt-images
cp -v ./aosp-<ver>/device/ti/am65xevm/fastboot.sh prebuilt-images
cp -v ./aosp-<ver>/out/host/linux-x86/bin/{simg2img,mkbootimg,fastboot,adb} prebuilt-images
cp -v ./aosp-<ver>/out/host/linux-x86/lib64/{libc++.so,libcutils.so,liblog.so,libselinux.so,libpcre2.so} prebuilt-images
cp -v ./u-boot_build/a53/u-boot.img prebuilt-images
cp -v ./u-boot_build/a53/tispl.bin prebuilt-images
cp -v ./u-boot_build/r5/tiboot3.bin prebuilt-images

1.3.3.2. Flashing procedure¶

Create an SD card containing MLO and u-boot.img using the create-sdcard.sh script provided in the SDK and then boot the target board from this external SD card.
Follow Run Setup Scripts to flash the rebuilt images (which have been copied to the prebuilt-images directory in the step above) to the onboard eMMC.