1*4882a593Smuzhiyun# 2*4882a593Smuzhiyun# Copyright (C) 2015 3*4882a593Smuzhiyun# 4*4882a593Smuzhiyun# Lukasz Majewski <l.majewski@majess.pl> 5*4882a593Smuzhiyun# 6*4882a593Smuzhiyun# 7*4882a593Smuzhiyun# SPDX-License-Identifier: GPL-2.0+ 8*4882a593Smuzhiyun 9*4882a593SmuzhiyunDevice Firmware Upgrade (DFU) - extension to use TFTP 10*4882a593Smuzhiyun===================================================== 11*4882a593Smuzhiyun 12*4882a593SmuzhiyunWhy? 13*4882a593Smuzhiyun---- 14*4882a593Smuzhiyun 15*4882a593Smuzhiyun* Update TFTP (CONFIG_UPDATE_TFTP) only supports writing 16*4882a593Smuzhiyuncode to NAND memory via TFTP. 17*4882a593Smuzhiyun* DFU supports writing data to the variety of mediums (NAND, 18*4882a593SmuzhiyuneMMC, SD, partitions, RAM, etc) via USB. 19*4882a593Smuzhiyun 20*4882a593SmuzhiyunCombination of both solves their shortcomings! 21*4882a593Smuzhiyun 22*4882a593Smuzhiyun 23*4882a593SmuzhiyunOverview 24*4882a593Smuzhiyun-------- 25*4882a593Smuzhiyun 26*4882a593SmuzhiyunThis document briefly describes how to use DFU for 27*4882a593Smuzhiyunupgrading firmware (e.g. kernel, u-boot, rootfs, etc.) 28*4882a593Smuzhiyunvia TFTP protocol. 29*4882a593Smuzhiyun 30*4882a593SmuzhiyunBy using Ethernet (TFTP protocol to be precise) it is 31*4882a593Smuzhiyunpossible to overcome the major problem of USB based DFU - 32*4882a593Smuzhiyunthe relatively low transfer speed for large files. 33*4882a593SmuzhiyunThis was caused by DFU standard, which imposed utilization 34*4882a593Smuzhiyunof only EP0 for transfer. By using Ethernet we can circumvent 35*4882a593Smuzhiyunthis shortcoming. 36*4882a593Smuzhiyun 37*4882a593SmuzhiyunBeagle Bone Black rev. C (BBB) powered by TI's am335x CPU has 38*4882a593Smuzhiyunbeen used as a demo board. 39*4882a593Smuzhiyun 40*4882a593SmuzhiyunTo utilize this feature, one needs to first enable support 41*4882a593Smuzhiyunfor USB based DFU (CONFIG_DFU_*) and DFU TFTP update 42*4882a593Smuzhiyun(CONFIG_DFU_TFTP) described in ./doc/README.update. 43*4882a593Smuzhiyun 44*4882a593SmuzhiyunThe "dfu" command has been extended to support transfer via TFTP - one 45*4882a593Smuzhiyunneeds to type for example "dfu tftp 0 mmc 0" 46*4882a593Smuzhiyun 47*4882a593SmuzhiyunThis feature does not depend on "fitupd" command enabled. 48*4882a593Smuzhiyun 49*4882a593SmuzhiyunAs of this writing (SHA1:8d77576371381ade83de475bb639949b44941e8c v2015.10-rc2) 50*4882a593Smuzhiyunthe update.c code is not enabled (CONFIG_UPDATE_TFTP) by any board in the 51*4882a593Smuzhiyuncontemporary u-boot tree. 52*4882a593Smuzhiyun 53*4882a593Smuzhiyun 54*4882a593SmuzhiyunEnvironment variables 55*4882a593Smuzhiyun--------------------- 56*4882a593Smuzhiyun 57*4882a593SmuzhiyunThe "dfu tftp" command can be used in the "preboot" environment variable 58*4882a593Smuzhiyun(when it is enabled by defining CONFIG_PREBOOT). 59*4882a593SmuzhiyunThis is the preferable way of using this command in the early boot stage 60*4882a593Smuzhiyunas opposed to legacy update_tftp() function invocation. 61*4882a593Smuzhiyun 62*4882a593Smuzhiyun 63*4882a593SmuzhiyunBeagle Bone Black (BBB) setup 64*4882a593Smuzhiyun----------------------------- 65*4882a593Smuzhiyun 66*4882a593Smuzhiyun1. Setup tftp env variables: 67*4882a593Smuzhiyun * select desired eth device - 'ethact' variable ["ethact=cpsw"] 68*4882a593Smuzhiyun (use "bdinfo" to check current setting) 69*4882a593Smuzhiyun * setup "serverip" and "ipaddr" variables 70*4882a593Smuzhiyun * set "loadaddr" as a fixed buffer where incoming data is placed 71*4882a593Smuzhiyun ["loadaddr=0x81000000"] 72*4882a593Smuzhiyun 73*4882a593Smuzhiyun######### 74*4882a593Smuzhiyun# BONUS # 75*4882a593Smuzhiyun######### 76*4882a593SmuzhiyunIt is possible to use USB interface to emulate ETH connection by setting 77*4882a593Smuzhiyun"ethact=usb_ether". In this way one can have very fast DFU transfer via USB. 78*4882a593Smuzhiyun 79*4882a593SmuzhiyunFor 33MiB test image the transfer rate was 1MiB/s for ETH over USB and 200KiB/s 80*4882a593Smuzhiyunfor pure DFU USB transfer. 81*4882a593Smuzhiyun 82*4882a593Smuzhiyun2. Setup update_tftp variables: 83*4882a593Smuzhiyun * set "updatefile" - the file name to be downloaded via TFTP (stored on 84*4882a593Smuzhiyun the HOST at e.g. /srv/tftp) 85*4882a593Smuzhiyun 86*4882a593Smuzhiyun3. If required, to update firmware on boot, put the "dfu tftp 0 mmc 0" in the 87*4882a593Smuzhiyun "preboot" env variable. Otherwise use this command from u-boot prompt. 88*4882a593Smuzhiyun 89*4882a593Smuzhiyun4. Inspect "dfu" specific variables: 90*4882a593Smuzhiyun * "dfu_alt_info" - information about available DFU entities 91*4882a593Smuzhiyun * "dfu_bufsiz" - variable to set buffer size [in bytes] - when it is not 92*4882a593Smuzhiyun possible to set large enough default buffer (8 MiB @ BBB) 93*4882a593Smuzhiyun 94*4882a593Smuzhiyun 95*4882a593Smuzhiyun 96*4882a593SmuzhiyunFIT image format for download 97*4882a593Smuzhiyun----------------------------- 98*4882a593Smuzhiyun 99*4882a593SmuzhiyunTo create FIT image for download one should follow the update tftp README file 100*4882a593Smuzhiyun(./doc/README.update) with one notable difference: 101*4882a593Smuzhiyun 102*4882a593SmuzhiyunThe original snippet of ./doc/uImage.FIT/update_uboot.its 103*4882a593Smuzhiyun 104*4882a593Smuzhiyun images { 105*4882a593Smuzhiyun update@1 { 106*4882a593Smuzhiyun description = "U-Boot binary"; 107*4882a593Smuzhiyun 108*4882a593Smuzhiyunshould look like 109*4882a593Smuzhiyun 110*4882a593Smuzhiyun images { 111*4882a593Smuzhiyun u-boot.bin@1 { 112*4882a593Smuzhiyun description = "U-Boot binary"; 113*4882a593Smuzhiyun 114*4882a593Smuzhiyunwhere "u-boot.bin" is the DFU entity name to be stored. 115*4882a593Smuzhiyun 116*4882a593Smuzhiyun 117*4882a593Smuzhiyun 118*4882a593SmuzhiyunTo do 119*4882a593Smuzhiyun----- 120*4882a593Smuzhiyun 121*4882a593Smuzhiyun* Extend dfu-util command to support TFTP based transfers 122*4882a593Smuzhiyun* Upload support (via TFTP) 123