[ECOS] Limited RAM space, relocate code to flash

[rob.wj.jansen@philips.com]

Hi all,

here is a nice puzzle.

My target board, with an ARM derivative on it, has got limited RAM space
but I do have about 32 Megs of flash.

The application is using a fairly large library with decompression, FFT
and other filtering algorithms - things I definitly will never change myself ...

I guess that it is possible to place these libraries (approx. 600 kBytes) and
maybe also parts of eCos (400 kBytes) could be placed into Flash as kind
of ROM library.

Has anyone ever tried this ? I'm looking for clues to get on the right track.
My best guess is that I should use --whole-archive to include all library code
in the binary and use the -Map to generate a map-file and convert this into
symbols to be included into my target.ld file.

Some data will have to be relocated from ROM to RAM and I have to reserve
a bit of ram for BSS, but that's not a big problem.

Thanks,

     Rob Jansen

Software Engineer
Competence Center Platforms
BU Mobile Communications
Meijhorst 60-10, 6537 KT Nijmegen, The Netherlands
Tel: +31-24-353-6329
Fax: +31-24-353-3613
mailto:Rob.WJ.Jansen@philips.com