U-Boot on QNAP TS-421

[Gordan Bobic <gordan@bobich.net>]

Hi,

I am trying to get an alternative distro running on my
QNAP TS-421, and the only Linux distro I can find that
has any support for it is Debian ARM, so here I am.

I have managed to defeat most of the problems with it
this far, but u-boot continues to be a problem.

TS-421 doesn't save it's u-boot variables on NAND. As
far as I can tell, they are always saved on a virtual
MTD partition (mtdblock4) in RAM, and overwritten on
every boot with the presets hard-coded in the u-boot
binary (mtdblock0).

I want to boot my distro with rootfs on a SATA disk
rather than /dev/ram as per the standard configuration
and having the console connected for it to boot
correctly every time is not a workable proposition.
(And no, I'm not prepared to use a micro-controller
that permanently sits on the serial port running
an expect script to interrupt the boot and change
the u-boot variables, that would just be silly.)

At the moment I am at the stage where I am seriously
considering just taking a hex editor to mtdblock0
and modifying the presets hard-coded in there to the
presets I want. This is not a particularly elegant
solution, it replaces one horrible bodge with
another equally horrible bodge.

Is there a better way? Is there an alternative
u-boot available for use on these, one that can
handle persistent variable saving?

Many thanks.

Gordan