1Android Fastboot
2~~~~~~~~~~~~~~~~
3
4Overview
5========
6The protocol that is used over USB is described in
7README.android-fastboot-protocol in same directory.
8
9The current implementation does not yet support the flash and erase
10commands.
11
12Client installation
13===================
14The counterpart to this gadget is the fastboot client which can
15be found in Android's platform/system/core repository in the fastboot
16folder. It runs on Windows, Linux and even OSX. Linux user are lucky since
17they only need libusb.
18Windows users need to bring some time until they have Android SDK (currently
19http://dl.google.com/android/installer_r12-windows.exe) installed. You
20need to install ADB package which contains the required glue libraries for
21accessing USB. Also you need "Google USB driver package" and "SDK platform
22tools". Once installed the usb driver is placed in your SDK folder under
23extras\google\usb_driver. The android_winusb.inf needs a line like
24
25   %SingleBootLoaderInterface% = USB_Install, USB\VID_0451&PID_D022
26
27either in the [Google.NTx86] section for 32bit Windows or [Google.NTamd64]
28for 64bit Windows. VID and PID should match whatever the fastboot is
29advertising.
30
31Board specific
32==============
33The fastboot gadget relies on the USB download gadget, so the following
34options must be configured:
35
36CONFIG_USBDOWNLOAD_GADGET
37CONFIG_G_DNL_VENDOR_NUM
38CONFIG_G_DNL_PRODUCT_NUM
39CONFIG_G_DNL_MANUFACTURER
40
41The fastboot function is enabled by defining CONFIG_CMD_FASTBOOT and
42CONFIG_ANDROID_BOOT_IMAGE.
43
44The fastboot protocol requires a large memory buffer for downloads. This
45buffer should be as large as possible for a platform. The location of the
46buffer and size are set with CONFIG_USB_FASTBOOT_BUF_ADDR and
47CONFIG_USB_FASTBOOT_BUF_SIZE.
48
49In Action
50=========
51Enter into fastboot by executing the fastboot command in u-boot and you
52should see:
53|GADGET DRIVER: usb_dnl_fastboot
54
55On the client side you can fetch the bootloader version for instance:
56|>fastboot getvar bootloader-version
57|bootloader-version: U-Boot 2014.04-00005-gd24cabc
58|finished. total time: 0.000s
59
60or initiate a reboot:
61|>fastboot reboot
62
63and once the client comes back, the board should reset.
64
65You can also specify a kernel image to boot. You have to either specify
66the an image in Android format _or_ pass a binary kernel and let the
67fastboot client wrap the Android suite around it. On OMAP for instance you
68take zImage kernel and pass it to the fastboot client:
69
70|>fastboot -b 0x80000000 -c "console=ttyO2 earlyprintk root=/dev/ram0
71|	mem=128M" boot zImage
72|creating boot image...
73|creating boot image - 1847296 bytes
74|downloading 'boot.img'...
75|OKAY [  2.766s]
76|booting...
77|OKAY [ -0.000s]
78|finished. total time: 2.766s
79
80and on the gadget side you should see:
81|Starting download of 1847296 bytes
82|........................................................
83|downloading of 1847296 bytes finished
84|Booting kernel..
85|## Booting Android Image at 0x81000000 ...
86|Kernel load addr 0x80008000 size 1801 KiB
87|Kernel command line: console=ttyO2 earlyprintk root=/dev/ram0 mem=128M
88|   Loading Kernel Image ... OK
89|OK
90|
91|Starting kernel ...
92