From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753019Ab1LUPmb (ORCPT ); Wed, 21 Dec 2011 10:42:31 -0500 Received: from mail.lippert-at.com ([62.80.22.186]:46456 "EHLO domex.lippertembedded.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751411Ab1LUPm2 (ORCPT ); Wed, 21 Dec 2011 10:42:28 -0500 Message-ID: <4EF1FE5C.6040101@LiPPERTEmbedded.de> Date: Wed, 21 Dec 2011 16:42:20 +0100 From: Jens Rottmann User-Agent: Thunderbird 1.5.0.14 (Windows/20071210) MIME-Version: 1.0 To: Andres Salomon CC: Thomas Gleixner , linux-kernel@vger.kernel.org, linux-geode@lists.infradead.org Subject: [PATCH] cs5535-clockevt: don't ignore MFGPT on SMP-capable kernels References: <4EE620A5.7080402@LiPPERTEmbedded.de> <20111212123131.502be350@queued.net> <4EE77416.8090907@LiPPERTEmbedded.de> <4EE8ECF3.6000900@LiPPERTEmbedded.de> <20111214104724.292b02d4@queued.net> In-Reply-To: <20111214104724.292b02d4@queued.net> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 21 Dec 2011 15:42:23.0960 (UTC) FILETIME=[2243D580:01CCBFF7] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org cs5535-clockevt: don't ignore MFGPT on SMP-capable kernels On SMP-capable kernels (e.g. generic distro kernel) the cs5535-clockevt driver loads but is not actually used. Setting cpumask to cpu_all_mask works for UP-only kernels, but if compiled for SMP - though still running on the same UP hardware - kernel/time/tick-common.c:tick_check_new_device() reads this as "non-cpu-local" and silently ignores the device. If we leave cpumask unset clockevents_register_device() will initialize it and the cs5535-clockevt driver will be used no matter how the kernel was compiled. Should anyone ever manage to stick a CS553x in an SMP system (is this even possible?) then a warning will be printed. This is fine as the cs5535-clockevt driver was never written/tested for SMP. If bisecting led you here this patch may have exposed a pre-existing MFGPT problem. Configure for UP-only and re-check. Signed-off-by: Jens Rottmann --- --- linux-3.2-rc6/drivers/clocksource/cs5535-clockevt.c +++ use_mfgpt_on_smp_kernels/drivers/clocksource/cs5535-clockevt.c @@ -100,7 +100,6 @@ static struct clock_event_device cs5535_ .set_mode = mfgpt_set_mode, .set_next_event = mfgpt_next_event, .rating = 250, - .cpumask = cpu_all_mask, .shift = 32 }; _