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Date: Tue, 15 Jan 2008 22:03:48 -0800
From: vb <vb@vsbe.com>
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To: linuxppc-embedded@ozlabs.org
Subject: MPIC ISU
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Greetings,

I am trying to write a BSP for an 8245 based device. One thing which
really gets me puzzled is the 'ISU' facility in
arch/powerpc/sysdev/mpic.c, there is also a notion of ISU-less
platforms, etc. I looked through the chip's programmer's reference,
even read the original AMD/Cypress OpenPIC specification - not a clue.

What is it, at the very least - what does ISU stand for?

I would really appreciate any hints,

thank you in advance,
/vb