Re: Memory management

From: Hans-Bernhard Broeker (broeker_at_physik.rwth-aachen.de)
Date: 03/05/05 

Date: 5 Mar 2005 16:49:05 GMT

Dani <daninm78NOSPAM@yahoo.es> wrote:
> Thanks for your comments Hans,

[Thanks for not top-posting with an unedited fullquote below, next
time.]

> I understand caching and memory protection are similar in some
> points but I would like to understand if it is necesary to reserve a
> part of RAM for the MMU if I don't use virtual adressing nor memory
> protection.

Yes, because the way MMUs usually work (I don't really know that of
the ARM), there is no such option as to say "I don't use" virtual
addressing or "I don't use" memory protection --- these are
implemented instead as a virtual memory mapping "physical == virtual"
a protection setup "all access to all address allowed", and it takes
MMU descriptor table memory to set up these configurations.
TANSTAAFL. 

-- 
Hans-Bernhard Broeker (broeker@physik.rwth-aachen.de)
Even if all the snow were burnt, ashes would remain.

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