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Date: Fri, 05 Jun 2009 19:58:23 +0300
From: Alexander Motin <mav@mavhome.dp.ua>
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To: Matthew Dillon <dillon@apollo.backplane.com>
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Cc: FreeBSD-Current <freebsd-current@freebsd.org>, freebsd-arch@freebsd.org
Subject: Re: WIP: ATA to CAM integration
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Matthew Dillon wrote:
>     It's unclear to me what this means.  Can we use NCQ to queue multiple
>     commands to multiple ports behind a single port multiplier in parallel
>     or can't we?  It's very confusing.

As I have said, without controller FIS Based Switching capability it is 
impossible. FBS defines separate memory areas for controller, to track 
there state of each drive behind PM. Without it, only one drive can be 
active at a time, as controller will not be able to track when each 
drive is able to receive next command..

-- 
Alexander Motin