Build Buildroot firmware

This chapter introduces the compilation process of Buildroot firmware. It is recommended to develop under Ubuntu 16.04 system environment. If you use other system versions, you may need to adjust the compilation environment accordingly.

Prerequisite

Download Firefly_Linux_SDK

  • Method One

Download via repo:

mkdir ~/proj/rk3288_linux_release_20210304/
cd ~/proj/rk3288_linux_release_20210304/
repo init  --no-clone-bundle --repo-url https://gitlab.com/firefly-linux/git-repo.git -u https://gitlab.com/firefly-linux/manifests.git -b master -m rk3288_linux_release.xml
  • Method Two

Download the SDK source code package.

Download: Linux_SDK.7z

After downloading, verify the MD5 code:

$ md5sum rk3288_linux_release_20210304.tgz
aa713b610db6f08570b2f9645eacbbf6  rk3288_linux_release_20210304.tgz

After confirming that it is correct, you can unzip:

mkdir ~/proj/
cd ~/proj/
tar -zxvf path/to/rk3288_linux_release_20210304.tgz

Sync Code

Execute the following command to synchronize the code:

# Enter the SDK root directory
cd ~/proj/rk3288_linux_release_20210304/

# Sync
.repo/repo/repo sync -l
.repo/repo/repo sync -c --no-tags
.repo/repo/repo start firefly --all

You can use the following command to update the SDK later:

.repo/repo/repo sync -c --no-tags

Directory

$ tree -L 1
.
├── app
├── buildroot                                               # Buildroot filesystem
├── build.sh -> device/rockchip/common/build.sh             # compile script
├── debian                                                  # Debian filesystem
├── device                                                  # config files
├── distro
├── docs                                                    # document
├── envsetup.sh -> buildroot/build/envsetup.sh
├── external
├── kernel
├── makefile -> buildroot/build/makefile
├── mkfirmware.sh -> device/rockchip/common/mkfirmware.sh   # link script
├── prebuilts                                               # cross-compile toolchain
├── rkbin
├── rkflash.sh -> device/rockchip/common/rkflash.sh         # flashing script
├── tools
├── u-boot
└── yocto

Set up compilation environment

sudo apt-get install repo git-core gitk git-gui gcc-arm-linux-gnueabihf u-boot-tools device-tree-compiler \
gcc-aarch64-linux-gnu mtools parted libudev-dev libusb-1.0-0-dev python-linaro-image-tools linaro-image-tools \
autoconf autotools-dev libsigsegv2 m4 intltool libdrm-dev curl sed make binutils build-essential gcc g++ bash \
patch gzip bzip2 perl tar cpio python unzip rsync file bc wget libncurses5 libqt4-dev libglib2.0-dev libgtk2.0-dev \
libglade2-dev cvs git mercurial rsync openssh-client subversion asciidoc w3m dblatex graphviz python-matplotlib \
libc6:i386 libssl-dev texinfo liblz4-tool genext2fs lzop libncurses5-dev libssl1.0.0 libssl1.0.0 expect

Build Linux-SDK

Precompile Configuration

There are configuration files for different board in device/rockchip/rk3288/, select the configuration file:

./build.sh firefly-rk3288-buildroot.mk

The configuration file will be connected to device/rockchip/.BoardConfig.mk, check the file to verify whether the configuration is successful.

Configruation content:

# Target arch
export RK_ARCH=arm                                              # 32-bit ARM
# Uboot defconfig
export RK_UBOOT_DEFCONFIG=firefly-rk3288                        # u-boot configuration
# Kernel defconfig
export RK_KERNEL_DEFCONFIG=firefly_linux_defconfig              # kernel configuration
# Kernel dts
export RK_KERNEL_DTS=rk3288-firefly                              # dts file
# Buildroot config
export RK_CFG_BUILDROOT=rockchip_rk3288                         # Buildroot configuration
# Recovery config
export RK_CFG_RECOVERY=rockchip_rk3288_recovery                 # recovery configuration
# parameter for GPT table
export RK_PARAMETER=parameter-buildroot.txt                     # partition table
# rootfs image path
export RK_ROOTFS_IMG=buildroot/output/$RK_CFG_BUILDROOT/images/rootfs.$RK_ROOTFS_TYPE   # filesystem path

Partial compilation

  • u-boot

./build.sh uboot
  • kernel

./build.sh kernel
  • recovery

./build.sh recovery
  • Buildroot filesystem

Compile the Buildroot filesystem and generate the compiled output directory in buildroot/output:

./build.sh buildroot

# Note: Be sure to compile the Buildroot filesystem as a normal user to avoid unnecessary errors.

Pack the firmware

Update each part of the .img link to the directory rockdev/:

./mkfirmware.sh

Pack the firmware, the firmware will be saved to the directory rockdev/pack/.

./build.sh updateimg

Automatic compilation

The automatic compilation will perform the above compilation and packaging operations to generate complete firmware.

./build.sh

Partition table

parameter

The parameter.txt file contains the partition information of the firmware. Take parameter-buildroot.txt as an example:

path: device/rockchip/rk3288/parameter-buildroot.txt

FIRMWARE_VER: 8.1
MACHINE_MODEL:RK3288
MACHINE_ID:007
MANUFACTURER:RK3288
MAGIC: 0x5041524B
ATAG: 0x00200800
MACHINE: 3288
CHECK_MASK: 0x80
PWR_HLD: 0,0,A,0,1
TYPE: GPT
CMDLINE: mtdparts=rk29xxnand:0x00002000@0x00004000(uboot),0x00002000@0x00006000(trust),0x00002000@0x00008000(misc),0x00010000@0x0000a000(boot),0x00010000@0x0001a000(recovery),0x00010000@0x0002a000(backup),0x00020000@0x0003a000(oem),0x00100000@0x0005a000(rootfs),-@0x0015a000(userdata:grow)
uuid:rootfs=614e0000-0000-4b53-8000-1d28000054a9

The CMDLINE attribute is where we are concerned. Take uboot as an example. In 0x00002000@0x00004000(uboot), 0x00004000 is the starting position of the uboot partition, 0x00002000 is the size of the partition, and so on.

package-file

The package-file is used to determine the required partition image and image path when packaging the firmware, and it needs to be consistent with the parameter.txt.

path: tools/linux/Linux_Pack_Firmware/rockdev/rk3288-package-file

# name          relative path
#
#hwdef          hwdef
package-file    package-file
bootloader      image/miniloaderall.bin
parameter       image/parameter.txt
trust           image/trust.img
uboot           image/uboot.img
misc            image/misc.img
boot            image/boot.img
recovery        image/recovery.img
rootfs          image/rootfs.img
oem             image/oem.img
userdata:grow   image/userdata.img
backup          RESERVED