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Re: redboot elf loader


On Mon, 2003-09-29 at 08:17, Mark Salter wrote:
> >>>>> Gary Thomas writes:
> 
> > On Mon, 2003-09-29 at 08:00, Mark Salter wrote:
> >> >>>>> Gary Thomas writes:
> >> 
> >> > I'd suggest that you leave this to your startup code.  Have it copy the
> >> > data from the VMA to the LMA - that's how we handle it in eCos.
> >> 
> >> Actually, we copy LMA to VMA. That is, for ROM startup the .data section
> >> has a VMA in RAM and an LMA in ROM. I tend to believe that the ELF loader
> >> should indeed be using LMA addresses.
> >> 
> 
> > How could this work for this example - loading via LMA into memory
> > that RedBoot clearly needs while running?
> 
> If that is the case, then the example is broken. My reading was that
> the VMA was 0x0 and LMA was somewhere where the other parts of the
> program lives. My point is that the LMA is where a loader should put
> sections (Load Memory Address) and VMA is where the running program
> actually accesses the sections.
> 

Agreed, and if LMA != VMA, then it would be up to the code (loaded 
program) to relocate it as appropriate.  So, the real question becomes
is the LMA stored in the p_paddr field (just making sure I understand
the terminology)?  If so, then the patch from Artur would be the correct
solution.

-- 
Gary Thomas <gary@mlbassoc.com>
MLB Associates


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