Compile Buildroot firmware

This chapter introduces the compilation process of Buildroot firmware.
It is recommended to develop in the Ubuntu 18.04 system environment.
If other system versions are used, the compilation environment may
need to be adjusted accordingly.

Compile SDK

Configuration before compilation

The configuration files of different board types are stored in the
"device/rockchip/rk3308/" directory

Go back to the SDK root directory and execute "build.sh" to select the
configuration file:

   ./build.sh roc-rk3308b-cc-plus-buildroot.mk

The configuration file will be linked to
"device/rockchip/.BoardConfig.mk", check this file to verify that the
configuration was successful.

Related configuration introduction:

   # Target arch
   export RK_ARCH=arm64 # 64-bit ARM architecture
   # Uboot defconfig
   export RK_UBOOT_DEFCONFIG=firefly-rk3308-debug-uart4 # u-boot configuration file
   # Kernel defconfig
   export RK_KERNEL_DEFCONFIG=firefly-rk3308b_linux_defconfig # kernel configuration file
   # Kernel dts
   export RK_KERNEL_DTS=rk3308b-roc-cc-plus-amic_emmc # dts file
   # Buildroot config
   export RK_CFG_BUILDROOT=firefly_rk3308_release # Buildroot configuration
   # Recovery config
   export RK_CFG_RECOVERY=firefly_rk3308_recovery # recovery configuration
   # parameter for GPT table
   export RK_PARAMETER=parameter-64bit-emmc.txt # Partition table
   # rootfs image path
   export RK_ROOTFS_IMG=rockdev/rootfs.${RK_ROOTFS_TYPE} # root file system path

Fully automatic compilation

Fully automated compilation performs all compilation and packaging
operations to generate the complete firmware.

   ./build.sh

Partial compilation

Compile u-boot

   ./build.sh uboot

compile kernel

   ./build.sh kernel

compile recovery

   ./build.sh recovery

Compile the Buildroot root filesystem

Compiling the Buildroot root filesystem will generate the build output
directory in "buildroot/output":

   ./build.sh buildroot

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

Package firmware

Update each part of the mirror link to the "rockdev/" directory:

   ./mkfirmware.sh

Pack the firmware, and the generated complete firmware will be saved
to the "rockdev/pack/" directory.

   ./build.sh updateimg

partition description

parameter partition table

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

Path: "device/rockchip/rk356x/parameter-buildroot-fit.txt"

   FIRMWARE_VER:8.1
   MACHINE_MODEL:RK3308
   MACHINE_ID:007
   MANUFACTURER: RK3308
   MAGIC: 0x5041524B
   ATAG: 0x00200800
   MACHINE: 3308
   CHECK_MASK: 0x80
   PWR_HLD: 0,0,A,0,1
   TYPE: GPT
   CMDLINE: mtdparts=rk29xxnand:0x00001000@0x00002000(uboot),0x00001000@0x00003000(trust),0x00000800@0x00004000(misc),0x0000A000@0x00004800(recovery),0x0000A000@0x0000E800(boot),0x00080000@0x00018800(rootfs),0x00020000@ 0x00098800(oem),-@0x00B8800(userdata:grow)
   uuid:rootfs=614e0000-0000-4b53-8000-1d28000054a9

The CMDLINE attribute is where we focus. Taking uboot as an example,
0x00001000 in 0x00001000@0x00004000(uboot) is the starting position of
the uboot partition, 0x00002000 is the size of the partition, and so
on.

package-file

The package-file 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 file.

Path: "tools/linux/Linux_Pack_Firmware/rockdev/rk3308-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
   boot Image/boot.img
   rootfs Image/rootfs.img
   recovery Image/recovery.img
   oem Image/oem.img
   userdata:grow Image/userdata.img
   misc Image/misc.img
   backup RESERVED
   #update-script update-script
   #recover-script recover-script

more content

"Firefly Buildroot User Manual"