From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Tue, 02 Mar 2010 15:32:06 +0100
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-help] ARM cached,non-cached memory
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To: Sinisa Denic <sinisa.denic@domain.hid>
Cc: Xenomai help <xenomai@xenomai.org>

Sinisa Denic wrote:
> Hi, last year working with xenomai 2.4.2-3 we met problem (BUG) with memory 
> caching on ARM AT91sam9260 arch. 
> Then we were advised using non-cached memory and we've used it till now,but in 
> our next application it has big performace slow down effect and I'm 
> interested is this BUG solved in latest 2.4.10 - xenomai 
> Regards,Sinisa

No, this is not a BUG in Xenomai. It is an architectural BUG^H^Hehaviour
of ARMv5, they have a VIVT cache, which is the cause of these issues.
Alternatively to using non-cached memory, you can use cached memory, and
flush cache when needed. Beware however defining "when needed", may be
complicated.

A note: Xenomai 2.4.10 is not the latest, the latest is Xenomai 2.5.1
and it has a lot of performance improvements for ARM.

-- 
					    Gilles.