compile

clone uboot code

git clone https://github.com/gl-inet/uboot-ipq40xx.git

clone sdk, ie. toolchain to compile uboot:

git clone https://github.com/gl-inet/openwrt-sdk-ipq806x.git

edit toplevel Makefile: change STAGING_DIR varable to point to openwrt-sdk-ipq806x/staging_dir you just clone.

make

the uboot binary will be: bin/openwrt-ipq40xx-u-boot-stripped.elf

using uboot web:

1. connect lan and PC by ethernet, your PC's ip should be 192.168.1.x
2. push reset button and power on, about 10 seconds later release the button, until wifi led stop flashing and the middle led light on.
3. using browser: access http://192.168.1.1 to flash firmware. access http://192.168.1.1/uboot.html to flash uboot.

tftp upgrade by uboot cmd line:

connect by serial port, use keyboard input

gl

to get into uboot cmd line.

setup tftpd server at ip 192.168.1.2, put firmware.bin at tftpd root directory. flash firmware(factory firmware or openwrt firmware) by:

run lf

setup tftpd server at ip 192.168.1.2, put openwrt-ipq40xx-u-boot-stripped.elf at tftpd root directory. flash uboot by:

run lu

automatic tftp upgrade:

1. setup tftpd server at ip 192.168.1.2, put firmware.bin at tftpd root directory.
2. connect the device and tfppd server, when the device power on, it will detect tftpd server to do flashing automatically.