FastBoot

Introduction

Fastboot is protocol used to update the flash file system in Android devices from a host over USB.

Prerequisites

Fastboot utils

It comes from Android SDK, under platform-tools directory.

• In Android windows SDK, it is named fastboot.exe.
• In Android Linux SDK, it is named fastboot

Drivers

The fastboot is support on both windows and Linux OS.

• On windows, please get driver for fastboot here: driver for fastboot.
• On Linux please add following udev rules. The following take example on Ubuntu OS, add following line into /etc/udev/rules.d/70-android.rules file. (if not exist, search the same function file or create it)

  SUBSYSTEM=="usb", ATTRS{idVendor}=="03EB", ATTRS{idProduct}=="6158", MODE="0666"
     

Starting Fastboot

EK board enter into fastboot mode

Press PB3 button on SAMA5D3xEK board, and power on, when you see the following message from console, then you can release the PB3 button and connect the EK board with Host PC.

...
DRAM:  512 MiB
BP3/USER1 button pressed...
NAND:  256 MiB
...
Hit any key to stop autoboot:  0
Fastboot entered...

Host PC make sure EK board enter into fastboot mode

On the PC we use fastboot utils to make sure the EK board enter into fastboot mode.

• On windows:

  $ fastboot.exe -i 0x03eb devices
  001234  fastboot
     

• On Linux OS:

  $ sudo fastboot -i 0x03eb devices
  001234  fastboot
     

Update Image through fastboot

Now, the flash boot support to update Linux device tree (dtb) file, Linux kernel image (kernel) file, Android system image (system) file, and Android user data image (userdata) file.

The following give an example about how to flash Android system image file on Linux OS.
The following steps is only for Jelly Bean. For Kit Kat, no need this step any more.

$ sudo fastboot -i 0x03eb oem format
...
OKAY [  0.005s]
finished. total time: 0.005s

Flash system to NAND flash.

$ sudo fastboot -i 0x03eb flash system system_ubifs-SAMA5D3-ANDROID-4.2.2_r1.1.img
sending 'system' (113920 KB)...
OKAY [ 41.905s]
writing 'system'...
OKAY [ 53.838s]
finished. total time: 95.744s
$ sudo fastboot -i 0x03eb reboot
rebooting...

finished. total time: 0.000s