separate kernel as code segment and data segment for linux ppc ?

[Wolfgang Denk]

In message <017b01c075f0$15265b50$bf0102c8 at sc.mcel.mot.com> you wrote:
>
> As all know, the kernel is resided in flash rom, then upon power-on, kernel
> is copied to RAM.
> I wonder if I can just put data segment to ram and leave code segment to
> FLASH, just as uClinux
> has done. such method will save some ram space, which makes sense on
> embedded solutions.

Does it really make sense? Flash is  more  expensive  than  RAM,  and
sometimes slower (especially if you have just a 8 or 16 bit wide boot
device). For all systems I've seen so far it was more efficient to be
able  to  store  a  compressed  image  in  flash, to reduce the flash
footprint on the expense of some RAM.

This has been discussed several times before on  this  mailing  list;
you might want to search the archives for all the other arguments pro
and contra.

Wolfgang Denk

--
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
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