To perform a TFTP recovery on this model:

• Set your IP address to 192.168.11.2
• Set a static arp entry for 192.168.11.1 to aa:bb:cc:dd:ee:ff (it doesn't seem to matter what mac address you use as long as you set it statically)
• TFTP an image while the red DIAG light is lit during boot. After successful upload DIAG light will flash slow, then fast.

The TFTP images will be under the "ar71xx" branch rather than the "atheros" branch… successfully uploaded trunk/ar71xx/openwrt-ar71xx-generic-whr-hp-g300n-squashfs-tftp.bin (trunk on 2013-02-12: BARRIER BREAKER (Bleeding Edge, r35572)).

Set your ethernet interface ip on 192.168.11.2

Set your ethernet interface netmask on 255.255.255.0

Add arp entry for 192.168.11.1 when the ethernet interface is up

sudo arp -s 192.168.11.1 aa:bb:cc:dd:ee:ff

Download the tftp version of the right firmware Change the directory of your prompt to the firmware download directory cd /Users/yourname/Downloads/

Send your firware image with tftp

tftp 192.168.11.1

*from this point, you're under tftp command prompt, the "tftp>" is the prompt tftp gives you, you just need to type the command AFTER that.

tftp> verbose

tftp> binary

tftp> trace

tftp> rexmt 1

tftp> timeout 60

Power on your router on and plug your ethernet on a LAN port

Send the command put until is success

tftp> put linux.bin

putting linux.bin to 192.168.11.1:linux.bin [octet] sent WRQ <file=linux.bin, mode=octet> tftp: sendto: Can't assign requested address

tftp> put linux.bin

putting linux.bin to 192.168.11.1:linux.bin [octet] sent WRQ <file=linux.bin, mode=octet> sent WRQ <file=linux.bin, mode=octet> sent WRQ <file=linux.bin, mode=octet> sent WRQ <file=linux.bin, mode=octet> sent WRQ <file=linux.bin, mode=octet> sent WRQ <file=linux.bin, mode=octet> sent WRQ <file=linux.bin, mode=octet> received ACK <block=0> sent DATA <block=1, 512 bytes> received ACK <block=1> sent DATA <block=2, 512 bytes> received ACK <block=2> sent DATA <block=3, 512 bytes> received ACK <block=3> sent DATA <block=4, 512 bytes> received ACK <block=4> sent DATA <block=5, 512 bytes> received ACK <block=5> sent DATA <block=6, 512 bytes> sent DATA <block=5633, 36 bytes> received ACK <block=5633> Sent 2883620 bytes in 8.0 seconds [2883620 bits/sec]

Wait and see ! ( at lease 10 min )

The ROUTER light will flash and stop !

Reboot and Enjoy