From owner-freebsd-current@FreeBSD.ORG  Wed May  6 10:16:28 2009
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To: Peter Jeremy <peterjeremy@optushome.com.au>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Wed, 06 May 2009 20:13:02 +1000."
	<20090506101301.GA17874@server.vk2pj.dyndns.org> 
Date: Wed, 06 May 2009 10:16:26 +0000
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Cc: freebsd-current@freebsd.org
Subject: Re: hardclock() sources 
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In message <20090506101301.GA17874@server.vk2pj.dyndns.org>, Peter Jeremy write
s:

>A better solution would seem to be to use a HPET periodic timer.

Part of the problem is discovering the timers location early enough.

We have long (10 years) talked about doing (at least) two scans of
the busses:

First scan to allocate missing resources
Second scan to get "important" hardware (console, timers)
Third scan to find the rest.

-- 
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.