From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: [PATCH] Append 'nohpet' in dom0 cmdline to prevent
	dom0 from using HPET
Date: Wed, 14 Oct 2009 12:58:02 -0700
Message-ID: <4AD62D4A.7030301@goop.org>
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To: "Wei, Gang" <gang.wei@intel.com>
Cc: Xen-devel <xen-devel@lists.xensource.com>, Keir Fraser <keir.fraser@eu.citrix.com>
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On 10/14/09 02:26, Wei, Gang wrote:
> Append 'nohpet' in dom0 cmdline to prevent dom0 from using HPET
>
> Xen is using HPET to wakeup cpu from deep c-states, so the HPET usage in dom0
> must be fobidden. In 2.6.18-xen, the HPET was by default disabled in config
> file. For upstream kernel built for pv dom0, it is not practical to disable dom0
> HPET usage in that way because the same image may be also using as bare metal 
> kernerl. So add cmdline option to do this thing for dom0.
>   

I think it would be better to unstatic disable_hpet() and call it from
Xen setup.  But as far as I can see hpet_init() should never be called
under Xen, because pv_time_ops won't be pointing to it, so there won't
be any attempt to use the hpet.

    J