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Re: How to setup the memory layout?


[ Old e-mail, I know ]

Holger Schurig wrote:
> I want RedBoot to be started directly after a reset. I can flash any
> image into the board using a self-made JTAG cable and ianflash.
> However, the documentation talks about gdb stubs, in some directory
> named "loaders", e.g. at
> http://sources.redhat.com/ecos/docs-latest/tutorials/arm/ecos-tutorial.d.html#pgfId=2813224
> after the heading "Overview". Is the documentation outdated?

That's only for certain targets. New targets should use RedBoot, which
*includes* a GDB stub. Don't worry too much about what the doc says in this
regard :).
 
> Should I set CYG_HAL_STARTUP to RAM or ROM?  The difference between
> those two sounds very fuzzy to me. RedBoot should start directly from
> Flash.

That would be "ROM" then.
 
> The board has Intel StrataFlash at physical address 0x0000 0000 and
> SRAM is at physical address 0xC000 0000. The configtool for Linux does
> not have a graphical memory setup, I have to edit the files in
> include/pkgconf manually, right?. However, for me it is not clear if
> something there is a physical addresses and virtual or if even some
> stuff is mixed.

This is to do with the linker, so use the virtual addresses. It's up to you
in the platform startup code to set up the MMU mappings, being aware that
at that point the code will have been *linked* at the virtual address, even
though the CPU is running it at the physical address. So you should use PC
relative addressing only at that stage for branches and so on.
 
> Would the following mlt_arm_sa11x0_accidp_rom.mlt file make sense?

Editting the MLT files directly is a pain. It's only used as a save file by
the (Windows) MLT. The .ldi and .h files are the files that are actually
used by the build system (and normally generated by the MLT from the .mlt
file).
 
Jifl
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