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Diffstat (limited to 'doc/README.android-fastboot')
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diff --git a/doc/README.android-fastboot b/doc/README.android-fastboot new file mode 100644 index 0000000000..f1d128caa9 --- /dev/null +++ b/doc/README.android-fastboot @@ -0,0 +1,91 @@ +Android Fastboot +~~~~~~~~~~~~~~~~ + +Overview +======== +The protocol that is used over USB is described in +README.android-fastboot-protocol in same directory. + +The current implementation does not yet support the flash and erase +commands. + +Client installation +=================== +The counterpart to this gadget is the fastboot client which can +be found in Android's platform/system/core repository in the fastboot +folder. It runs on Windows, Linux and even OSX. Linux user are lucky since +they only need libusb. +Windows users need to bring some time until they have Android SDK (currently +http://dl.google.com/android/installer_r12-windows.exe) installed. You +need to install ADB package which contains the required glue libraries for +accessing USB. Also you need "Google USB driver package" and "SDK platform +tools". Once installed the usb driver is placed in your SDK folder under +extras\google\usb_driver. The android_winusb.inf needs a line like + + %SingleBootLoaderInterface% = USB_Install, USB\VID_0451&PID_D022 + +either in the [Google.NTx86] section for 32bit Windows or [Google.NTamd64] +for 64bit Windows. VID and PID should match whatever the fastboot is +advertising. + +Board specific +============== +The fastboot gadget relies on the USB download gadget, so the following +options must be configured: + +CONFIG_USBDOWNLOAD_GADGET +CONFIG_G_DNL_VENDOR_NUM +CONFIG_G_DNL_PRODUCT_NUM +CONFIG_G_DNL_MANUFACTURER + +The fastboot function is enabled by defining CONFIG_CMD_FASTBOOT and +CONFIG_ANDROID_BOOT_IMAGE. + +The fastboot protocol requires a large memory buffer for downloads. This +buffer should be as large as possible for a platform. The location of the +buffer and size are set with CONFIG_USB_FASTBOOT_BUF_ADDR and +CONFIG_USB_FASTBOOT_BUF_SIZE. + +In Action +========= +Enter into fastboot by executing the fastboot command in u-boot and you +should see: +|GADGET DRIVER: usb_dnl_fastboot + +On the client side you can fetch the bootloader version for instance: +|>fastboot getvar bootloader-version +|bootloader-version: U-Boot 2014.04-00005-gd24cabc +|finished. total time: 0.000s + +or initiate a reboot: +|>fastboot reboot + +and once the client comes back, the board should reset. + +You can also specify a kernel image to boot. You have to either specify +the an image in Android format _or_ pass a binary kernel and let the +fastboot client wrap the Android suite around it. On OMAP for instance you +take zImage kernel and pass it to the fastboot client: + +|>fastboot -b 0x80000000 -c "console=ttyO2 earlyprintk root=/dev/ram0 +| mem=128M" boot zImage +|creating boot image... +|creating boot image - 1847296 bytes +|downloading 'boot.img'... +|OKAY [ 2.766s] +|booting... +|OKAY [ -0.000s] +|finished. total time: 2.766s + +and on the gadget side you should see: +|Starting download of 1847296 bytes +|........................................................ +|downloading of 1847296 bytes finished +|Booting kernel.. +|## Booting Android Image at 0x81000000 ... +|Kernel load addr 0x80008000 size 1801 KiB +|Kernel command line: console=ttyO2 earlyprintk root=/dev/ram0 mem=128M +| Loading Kernel Image ... OK +|OK +| +|Starting kernel ... |