From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Stultz Subject: Re: Minimum timing resolution in Ubuntu/Linaro on the PandaBoard ES Date: Wed, 08 Feb 2012 09:05:02 -0800 Message-ID: <1328720702.8119.11.camel@js-netbook> References: <4F31A91B.8080106@umich.edu> <4F32063F.1020607@linaro.org> <51DAA6EF-1C3B-4964-8447-893D295E51A1@umich.edu> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from e33.co.us.ibm.com ([32.97.110.151]:48215 "EHLO e33.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757331Ab2BHRGI (ORCPT ); Wed, 8 Feb 2012 12:06:08 -0500 Received: from /spool/local by e33.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 8 Feb 2012 10:05:52 -0700 Received: from d03relay05.boulder.ibm.com (d03relay05.boulder.ibm.com [9.17.195.107]) by d03dlp03.boulder.ibm.com (Postfix) with ESMTP id A5E7C19D8052 for ; Wed, 8 Feb 2012 10:05:28 -0700 (MST) Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d03relay05.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q18H5FFK118044 for ; Wed, 8 Feb 2012 10:05:17 -0700 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q18H5ARH018869 for ; Wed, 8 Feb 2012 10:05:11 -0700 In-Reply-To: <51DAA6EF-1C3B-4964-8447-893D295E51A1@umich.edu> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Andrew Richardson Cc: Dmitry Antipov , linaro-dev@lists.linaro.org, linux-omap@vger.kernel.org On Wed, 2012-02-08 at 04:32 -0500, Andrew Richardson wrote: > Ah, very interesting. > > dmesg | grep clock > [ 0.000000] OMAP clockevent source: GPTIMER1 at 32768 Hz > [ 0.000000] sched_clock: 32 bits at 32kHz, resolution > 30517ns, wraps every 131071999ms Hrm. So 30us is still much smaller then the 2.5ms you were seeing. So that doesn't fully explain the behavior. thanks -john