Build Kernel

Install Development Packages

Install development packages：

   sudo apt-get install build-essential lzop libncurses5-dev libssl-dev
   # If using 64 bits Ubuntu, you need also:
   sudo apt-get install libc6:i386

Install mkbootimg utility:

   git clone https://github.com/neo-technologies/rockchip-mkbootimg.gitcd rockchip-mkbootimg
   make && sudo make install

If you have already downloaded the Firefly-RK3128 Android SDK, the
kernel source and cross compiling toolchain are in SDK/kernel and
SDK/prebuilts respectively. Please skip to next step.If not, please
download the kernel source code and Android's arm-eabi-4.6 cross
compiling toolchain.Download the kernel source code：

   git clone https://bitbucket.org/T-Firefly/fireprime-kernel.git

Note: This is Linux kernel source code in separated source repository,
which is extracted from fireprime branch of Firenow-Lollipop Android
SDK, for convenience of users who only want the kernel source code
instead of the huge sdk.For Android's arm-eabi-4.6 cross compiling
toolchain, you may look around to see if any  local Android SDK has
prebuilts/gcc/linux-x86/arm/arm-eabi-4.6. If there is, you can reuse
it; otherwise download from

here

 and extract it.

Compile Kernel

Compile Image

If you are not compiling kernel in the SDK, you need to specify ARCH
and CROSS_COMPILE first:

   export ARCH=arm
   export CROSS_COMPILE=/path/to/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/bin/arm-eabi-

In the kernel source directory, execute:

   make fireprime-linux_defconfig
   make -j8 rk3128-fireprime.img

Compile Kernel Modules

Run:

   make modules
   mkdir modules_insatll
   make INSTALL_MOD_PATH=./modules_install modules_insatll

Copy the kernel module files to the root file system:

   rsync -av ./modules_install/ /path/to/your/rfs/

You can also copy to the development board, using ssh remote
connection:

   rsync -av ./modules_install/ root@<Board IP>:/

Clean up the module install directory (it  contains links which impact
compilation of Android SDK):

   rm -rf ./modules_install

Create linux-boot.img

Create Initramfs

The kernel will load the initramfs as the first root file system. It
is in charge of finding the actual root device, load it then finally
switch to it.

   git clone -b fireprime https://github.com/TeeFirefly/initrd.gitmake -C initrd

Package Kernel and Initramfs

Pack kernel and initramfs into linux-boot.img:

   truncate -s "%4" initrd.img
   mkbootimg --kernel arch/arm/boot/zImage --ramdisk initrd.img -o linux-boot.img

Modify Parameter File

The root file system can reside on different partitions in different
storage devices (eMMC, TF card or USB disk, etc). It must be specified
in the kernel's command line. There is a CMDLINE in the paramter file.
Add one of below according to your need: (# and contents after are
comments, no need to enter):

   root=/dev/block/mtd/by-name/linuxroot        # flash partition named "linuxroot"
   root=/dev/mmcblk0p1          # First partition of TF card
   root=/dev/sda1               # First partition of USB disk
   root=LABEL=linuxroot         # Partition whose label is "linuxroot"

This is the parameter file used in official dual boot firmware, for
reference only:

   FIRMWARE_VER:5.1
   MACHINE_MODEL:rk312x
   MACHINE_ID:007
   MANUFACTURER:RK30SDK
   MAGIC: 0x5041524B
   ATAG: 0x60000800
   MACHINE: 312x
   CHECK_MASK: 0x80
   KERNEL_IMG: 0x60408000
   #RECOVER_KEY: 1,1,0,20,0
   CMDLINE:console=ttyFIQ0,115200 earlyprintk androidboot.hardware=rk30board androidboot.console=ttyFIQ0 board.ap_has_alsa=0 init=/init initrd=0x62000000,0x00800000 mtdparts=rk29xxnand:0x00002000@0x00002000(uboot),0x00002000@0x00004000(misc),0x00008000@0x00006000(resource),0x00008000@0x0000e000(kernel),0x00010000@0x00016000(boot),0x00010000@0x00026000(recovery),0x0001a000@0x00036000(backup),0x00040000@0x00050000(cache),0x00002000@0x00090000(kpanic),0x00180000@0x00092000(system),0x00002000@0x00212000(metadata),0x00200000@0x00214000(userdata),0x00020000@0x00414000(radical_update),-@0x00434000(user)

Flash to Device

Please reference

Flash image

, flash parameter file and its corresponding partition images.If you
are upgrading from official firmware, flash linux-boot.img to the
following partion, according to the firmware type:


If the root filesystem image is not flashed yet, you can download the
prebuilt image, or customize your own one, and flash it to the
partition specified in parameter file.