[PATCH v4 1/9] CONFIG_NR_DRAM_BANKS: Remove unreferenced code as its always defined

Wolfgang Denk wd at denx.de
Tue Aug 18 14:19:21 CEST 2020

Dear Stefan,

In message <8ddb672c-956c-68d2-ceb4-d77f96cdf4e4 at denx.de> you wrote:
> > Especially the default value of 4 makes no sense to me - whiy is
> > this not 1?
> I can't really tell. I can only assume, that it originates from this
> patch:

Yes, probably.

I think the issue here resutlsfromt he fact that those who worked on
the patches came primarily from architectures where this array of
banks has been used; for Power Architecture systems this has (for a
long, long time) not been the case - there we would map several
memory banks (after determining their respecitve sizes) into one
contiguous area of memory starting at address 0.

So on all such system the definition of this array meand code and
data overhead, as it is not needed.

> > ...thus futher hiding where we just lost another lof of memory, for
> > no advantage.
> > 
> > Sic...
> I'm not sure, what you mean with "lost lot of memory"? We carried
> referenced code for ~2 years, which this patch series now tries to
> solve.

See above. On most PPC systems this array of sizes and addresses is
not needed at all, and _if_ code is changed to use such an array, it
should not waste even more memory be defining room for 4 banks where
there usually will be only one.

Sorry, I know that you are not to blame for that...

Best regards,

Wolfgang Denk

DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Make it right before you make it faster.

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