====== Use fastboot ======

Fastboot is a method to quickly upgrade each partition package of Android.

===== Install fastboot tool =====

You can follow [[products:sbc:common:development:adb#install-adb-tool| install adb tool]] to install fastboot tool.

===== Enter fastboot mode =====

  - Connect the PC host and board with USB cable.
  - Refer the documentation ([[setup-serial-tool| VIM1/2/3/3L/4/1S/Edge1 ]] / [[products:sbc:edge2/development:setup-serial-tool| Edge2 ]]) to setup your serial tool.
  - Once again, make sure you've done the correct connections and setup.
  - Hit ''Enter'' keys at the moment of bootup to stop autoboot. This step will let the board boot into U-Boot Mode.
  - Type ''fastboot 1'' command to enter the burning mode.

```shell
kvim1s# fastboot 1
PHY2=00000000fe03a020,phy-base=0xfe03e000
serial num: 0000000000
crg_udc_epcx_update_dqptr Cannot update dqptr for ep0
```

===== Unlock bootloader =====

To use fastboot to flash the machine, you must first unlock the bootloader, otherwise the machine cannot be flashed.

After entering the fastboot mode, run the following command to unlock:

```shell
$ fastboot flashing unlock
$ fastboot flashing unlock_critical
```
```shell
C:\Users\25348>fastboot flashing unlock
...
OKAY [  0.372s]
finished. total time: 0.377s

C:\Users\25348>fastboot flashing unlock_critical
...
OKAY [  0.007s]
finished. total time: 0.009s

C:\Users\25348>
```

===== Fastboot commands =====

```shell
$ fastboot devices
$ fastboot reboot
$ fastboot reboot-bootloader
$ fastboot flashing unlock_critical
$ fastboot flashing unlock
$ fastboot flashing lock_critical
$ fastboot flashing lock
$ fastboot flashing get_unlock_ability
$ fastboot flash bootloader bootloader.img
$ fastboot flash bootloader-boot0 bootloader.img
$ fastboot flash bootloader-boot1 bootloader.img
$ fastboot flash dts dt.img
$ fastboot flash dtbo dtbo.img
$ fastboot flash vbmeta vbmeta.img
$ fastboot flash logo logo.img
$ fastboot flash boot boot.img
$ fastboot flash super super.img        # not support burn logic partition in bootloader
$ fastboot flash recovery recovery.img
$ fastboot erase env/param/tee/boot/recovery/dtb
$ fastboot -w
$ fastboot format cache
$ fastboot getvar all
$ fastboot getvar is-userspace          # return no in bootloader
$ fastboot getvar is-logical:boot       # return no, others
$ fastboot getvar is-logical:system     # return yes, system/odm/vendor/product
$ fastboot getvar super-partition-name  # return super
```
===== Update kernel =====

```shell
$ fastboot flash vendor_boot /path/to/vendor_boot.img
```

===== Update dtb =====

```shell
$ fastboot flash vendor_boot_a /path/to/vendor_boot.img
```
===== Exit fastboot and restart the device =====

```shell
$ fastboot reboot
```

===== See also =====

[[https://source.android.com/docs/setup/test/running | Fastboot ]].