ROM-BACKUP.txt

Fernly doesn't require changing a firmware stored in FlashROM of
your device - it runs completely from RAM. You may still want
to backup the original firmware for various reasons. Following
gives a walkthru how to do this.

1. Check out the latest flashrom HEAD:

svn co http://code.coreboot.org/svn/flashrom/trunk flashrom

Using latest HEAD is recommended, as it may have more chip definitions,
and there's less chance it won't recognize your FlashROM.

2. Apply flashrom-fernvale.patch from fernly:

patch -p0 <flashrom-fernvale.patch

3. You may need to install libusb-0.1 development headers to build it
(0.1 is "old" libusb, many projects use modern 1.0 version). For ubuntu:

apt-get install libusb-dev

4. Build with:

make WARNERROR=no

5. Start fernly without "-s" (shell) switch:

./build/fernly-usb-loader -w /dev/ttyUSB0 ./build/usb-loader.bin ./build/firmware.bin

6. Run flashrom to dump device FlashROM to a file:

./flashrom --programmer fernvale_spi:dev=/dev/ttyUSB0 --read flash.dat

If you're unlucky, it may report that it cannot recognize your device has
a ROM it can't recognize. If so, follow flashrom documentation on what to do.

Otherwise, expect that reading 16MB of flash to take up to 10 minutes -
without any progress indicator or something.

7. Refer to flashrom documentation for writing (generally it's as simple
as giving --write option instead of --read).