Subject: Re: Running from ROM

From: Kent Borg <[email-masked]>
Date: Tue, 6 Jun 2000 09:39:47 -0400

Joe Green <[email-masked]> wrote:
>The project Mark mentioned is specifically for running the kernel
>from ROM.

That doesn't sound horribly complicated.  Groady details to be sure,
but ~conceptually~ easy.

>Are you also asking about running application code from ROM?

Yes.  I realize that it can frequently make sense to compress and load
into RAM, but there is a significant chance that running directly from
ROM could be sensible for us.  Interestingly, part of the reason might
be a "real space" approach, that is, wanting to be deterministic about
whether a given operation can successfully run.  In a system where
sometimes every byte of RAM is needed, I can imagine circumstances
where, depending on the order of operations, some RAM-hungry
operations could sometimes fail and sometimes succeed.  Getting one
more "it's virtual, it does the right thing"-aspect out of the system
could help.  Or maybe not.

So back to the question, it appears there are not scads of people
already doing this.  Suggestions on approaches?  As I let my
imagination run only ugly solution fragments come out on this.

Thanks,

-kb, the Kent who needs to keep reading Rubini's book to learn more
about how the normal case works.

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