From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: Re: [PATCH v2 2/5] x86/time: Always count s_time from
 Xen	boot
Date: Mon, 3 Mar 2014 10:59:17 +0000
Message-ID: <53146085.6060400@citrix.com>
References: <1393613824-13230-1-git-send-email-andrew.cooper3@citrix.com>
	<1393613824-13230-3-git-send-email-andrew.cooper3@citrix.com>
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To: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Tim Deegan <tim@xen.org>, Keir Fraser <keir@xen.org>, Jan Beulich <JBeulich@suse.com>, Xen-devel <xen-devel@lists.xen.org>
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On 28/02/14 18:57, Andrew Cooper wrote:
> From: Tim Deegan <tim@xen.org>
> 
> In the early-boot clock, before the calibration routines kick in,
> count time from Xen boot rather than from when the BSP's TSC was 0.
> 
> Signed-off-by: Tim Deegan <tim@xen.org>
> 
> Stash the timestamp in head.S as a good approximation of when we actually
> started, rather than measuing "time since we ran early_time_init()"

Is this difference/accuracy interesting?  It seems more obvious to me to
just read the TSC in early_time_init().

David