Re: [ECOS] MBX redboot

[Jonathan Larmour <jlarmour at redhat dot com>]

Jesper Skov wrote:
> 
> >>>>> "Jonathan" == Jonathan Larmour <jlarmour@redhat.com> writes:
> 
> >> "Natarajan, Mekala (CTS)" wrote:
> >>
> >> How to debug the rom monitor(redboot). 
> 
> Jonathan> No you can't debug redboot itself very easily because even a
> Jonathan> RAM based RedBoot will steal most of the exception vectors
> Jonathan> etc. for itself (as will any application that has GDB stubs
> Jonathan> included). And quite right too - you wouldn't be able to use
> Jonathan> a RAM based RedBoot to upgrade if it still relied on the
> Jonathan> ROM/Flash based one to run.
> 
> Actually, debugging the vector magic can be done simply by changing
> the location of the virtual vector table in the RAM application
> (RedBoot).
> 
> Then the ROM monitor can be used for debugging most of the RAM app
> startup initialization, including virtual vector setup. You may have
> to hack a few things to prevent the RAM app from taking over exception
> vectors and/or serial control. But it's definitely doable.

Well, yes, if you want to explicitly override this behaviour in the sources
then fair enough - anything is possible :-). Although I suppose it might be
worthwhile you adding this to your current draft of the porting guide as a
tip?

Jifl
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