RE: [ECOS] backup strategy for loading Linux kernel in Redboot FIS ?

["Gary Thomas" <gary at mlbassoc dot com>]

Winkler Andreas said:
>> Are you thinking of the question that Andreas asked before?
>> If so, then this reads like the same question, so Andreas, you may want to
>
>> rephrase your question since it sounds like the same one again!
>
> As I didn't understand the answer of Andrew
>
>>> Enable redboots CRC checking. The boot script will first copy the
>>> image from flash to ram and then do a go. In normal cases Linux then
>>> completely takes over and redboot is dead. But if the CRC is wrong,
>>> the copy fails and the go will also fail. You can then make your boot
>>> script copy a second image and then execute it.
>
> I tried to ask my remaining question in other words. Sorry, this was no good
> idea.
>
> I don't know how to enable redboots CRC checking, couldn't find it in the
> users guide.

This will happen automatically with the default redboot template.
Note: it only applies to the "fis" package.  When images are written
to the FIS, a CRC will be calculated and saved with the image.  When
you read the image into RAM ("fis load"), the CRC is verified and if
it fails, then the entry point address is suppressed.  This is normally
used to prevent the "go" command from executing.

> And I just tried the command "go 50000" to look whether redboot makes any
> check before executing.

When an entry point is explicitly specified, as you have done, the CRC
check is ignored.  Here's how CRC checking is expected to work:

  RedBoot> fis load program
  ** Warning: CRC check failed!
  RedBoot> go
  ** No entry point specified - failed
(the messages are from memory, not precise...)

> It didn't, just ran away.

Just as you told it to do :-)





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