From owner-freebsd-arch@FreeBSD.ORG  Wed Apr  9 15:38:17 2008
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To: Marcel Moolenaar <xcllnt@mac.com>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Wed, 09 Apr 2008 08:36:17 MST."
	<FD6E3ED5-5315-4F39-9EF0-8C0FC1683802@mac.com> 
Date: Wed, 09 Apr 2008 15:38:14 +0000
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Sender: phk@critter.freebsd.dk
Cc: arch@freebsd.org, John E Hein <jhein@timing.com>
Subject: Re: sync/async [was: Re: tt_ioctl] 
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In message <FD6E3ED5-5315-4F39-9EF0-8C0FC1683802@mac.com>, Marcel Moolenaar wri
tes:

>I think the complexity or problems stem from the fact that
>there's a single driver. With scc(4) the design is such that
>the driving is left to subordinate drivers like uart(4) and
>the only thing that scc(4) does is arbitration.

Yeah, we have the same thing over at the ppbus.

I remember talking with Warner about making this a facility in
newbus instead, but I think we had too much beer and too little
time :-)

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.