tree 2b64b9e06e8f63f8e688ccc7c592c758b181f033
parent 6fa8750539b0b31c196d7e98772edb0c63e8470e
author Jan Kundrát <jan.kundrat@cesnet.cz> 1515777515 +0100
committer Jan Kundrát <jan.kundrat@cesnet.cz> 1515777515 +0100

clearfog: Implement USB booting

Here's how to load this from a possible bricked device:

1) Set the boot switches to 01001 (yes, it's different from what the doc
says)
2) Load the bootloader via UART, e.g.:
  `./tools/kwboot -b ./u-boot-spl.kwb -t -p /dev/ttyUSB0`
3) Interrupt U-Boot's autoboot to get a prompt
4) Plug a USB flash with images/usb-flash.img loaded
5) One on the U-Boot prompt, execute:
  `usb start; fatload usb 0:1 00800000 usb-boot.scr; source 00800000`
6) Get a nice emergency shell

Change-Id: Icef4badc9105bbed78ad949c060c0a46e9ff7f76