From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kevin Hilman Subject: Re: [PATCH v2] OMAP:GPTIMER:1ms tick generation correction Date: Mon, 21 Jun 2010 08:54:16 -0700 Message-ID: <8739wg2xg7.fsf@deeprootsystems.com> References: <1277151798-26232-1-git-send-email-tarun.kanti@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pv0-f174.google.com ([74.125.83.174]:44801 "EHLO mail-pv0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755853Ab0FUPyX (ORCPT ); Mon, 21 Jun 2010 11:54:23 -0400 Received: by pvh11 with SMTP id 11so299705pvh.19 for ; Mon, 21 Jun 2010 08:54:20 -0700 (PDT) In-Reply-To: <1277151798-26232-1-git-send-email-tarun.kanti@ti.com> (Tarun Kanti DebBarma's message of "Tue\, 22 Jun 2010 01\:53\:18 +0530") Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Tarun Kanti DebBarma Cc: linux-omap@vger.kernel.org, R Sricharan Tarun Kanti DebBarma writes: > Generation of 1ms granular GPTIMER events using 32KHz or system > clocks as inputs does not have whole number count value to load > into the register. This inaccurate count value with respect to 1ms > period leads to time drift subsequently. OMAP3 and later silicons > have dedicated registers for GPTIMER1, GPTIMER2 and GPTIMER10, > which can be programmed with computed values to keep this error > controlled within specified limit. > > Version 2: > (i) optimized omap_dm_timer_ms_correction() function and corrected > error in computing the positive and negative increments. > (ii) typo corrections in comment section and warning removal related > to 80-character limit > > Tested on Zoom3 using Linus tree. > > Signed-off-by: R Sricharan > Signed-off-by: Tarun Kanti DebBarma Please coordinate this change with the GPTIMER hwmod changes. The timers that have/need this feature should be flagged at the hwmod level (probably by a dev_attr flag.) Kevin