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initializing DiscOnChip with etrax100boot?



When using a DiscOnChip instead of NOR flash in an 
Etrax100LX based device, the following initialization
steps have to be taken, when the components are put 
together 'out of the box':

-put a custom bootloader (GRUB?) on the DiscOnChip
-put the kernel image on the DOC
-format the remainder of the DOC, or
put a filesystem image in place.

After this, the system should be able to
boot from the DiscOnChip.

Now I think this requires quite a few huge changes
in the clientside part of the network bootloader.
Possibly (or should I say probably) the 8K limit
will be crossed.

I guess that in that case a second stage bootloader 
should be  written, loaded into ram, and started?

Now a different (and simpler) aproach might be
the following:

-Create standard devboard images containing the
necessary tools to format the DOC, and an image
of the new DOC bootloader, and whatever else is needed.

-Use 'ktest' to load the whole thing into ram, and
boot into it. I guess this should work without
having access to the flash?

-Now, from this system running entirely from ram,
prepare the DOC as needed (possibly from a script
that starts at bootup)

-then reboot into the prepared DOC.

My plan is to first follow the second solution, 
then maybe later on try to implement the first solution,
for higher initialization speed, and probably
easier maintenance (I think solution 2 would require
building two different image sets, one contained inside
the other...)

Can someone please give some advice on which route
to follow to make this work?

Best regards,

Pieter Grimmerink