Réf. : Re: starting RAM adress for linux kernel

[Wolfgang Denk]

Dear Sphie,

in message <OFF1C6B550.9120AF42-ONC1257015.004EFCD3 at brime.fr> you wrote:
> 
> we need to have the start of Ram at 0x0300 0000 because we use the command
> mem=40M (for uboot) to force Linux
> in the low part of memory and to reserve the high part of memory (218M
> exactly ) for ioremap (for our application) but we keep

I don't see any reason why this would prevent you  from  mapping  the
RAM at physical address 0.

> the same flash mapping (to avoid more problems).

I don't know which problems you want to avoid by your  chosen  memory
map,  but  I  guess  that the problems you *cause* by this choice are
more, and more severe.

> Is the only solution is to inverse the mapping with Ram from 0 to 258M and
> the flash above ?

Yes.

> Finally, will Busybox work with Ram starting at 0x03000000 ?

No, it will not, as BB is application code which requires  a  running
kernel, and your kernel will not run with such a mapping.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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