Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758937AbYCAW6Z (ORCPT ); Sat, 1 Mar 2008 17:58:25 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755172AbYCAW6P (ORCPT ); Sat, 1 Mar 2008 17:58:15 -0500 Received: from smtp123.sbc.mail.sp1.yahoo.com ([69.147.64.96]:27119 "HELO smtp123.sbc.mail.sp1.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1755012AbYCAW6P (ORCPT ); Sat, 1 Mar 2008 17:58:15 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=pacbell.net; h=Received:X-YMail-OSG:X-Yahoo-Newman-Property:From:To:Subject:Date:User-Agent:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-Disposition:Message-Id; b=XZ7/3thsJHwdsrKlS2VWZOy8F9iKcG3ahkMKdMzOQsG2rw/Hgt9aQYWmkOC5b9yq+Ophdhw2Hjl1sgaNyRTxaWVAzc00ZTvjKk0XQ7A21ftsQU36n/mATB90xFKlTjvBL84ScQGUzno7SSNaTiONO7KQkym7vLP5UWk7eLGLW5g= ; X-YMail-OSG: gTL6DpsVM1kBzd3zG_YcGu9Oyw_j6n2lbxidA49YXnEZc9J1gvQ1elWfI8fAiqzzX4p0q4MOon9Mh1odPpYXhjhXzfZSQeZgdSJXZGEXfJRYtbEDdg-- X-Yahoo-Newman-Property: ymail-3 From: David Brownell To: Bosko Radivojevic Subject: Re: High resolution timers on AT91SAM926x Date: Sat, 1 Mar 2008 14:57:40 -0800 User-Agent: KMail/1.9.6 Cc: lkml MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200803011457.40857.david-b@pacbell.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1212 Lines: 30 > Is there a way to enable high resolution timers on AT91SAM926x? Update PIT to support the clocksource/clockevent framework: http://marc.info/?l=linux-arm-kernel&m=119940724711435&w=2 Declare timer/counter block platform devices: http://marc.info/?l=linux-arm-kernel&m=120302318811110&w=2 Use timer/counter blocks for better clocksource and clockevents: http://marc.info/?l=linux-kernel&m=120373043520279&w=2 http://marc.info/?l=linux-kernel&m=120373063320487&w=2 The focus in that last patch is on NO_HZ support -- so the clockevents run at 32 KiHz (about 31 usec precision for HRT) to allow overall HZ to run below 1 where practical. If you need even higher precision, you could update that clockevent code to use a different base clock. Those last two patches are in some MM tree, and Haavard has some updates to then (which don't much affect functionality). I understand the upcoming 2.6.24-at91 patch will include the first two patches. - Dave -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/