From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755890Ab3AUXXc (ORCPT ); Mon, 21 Jan 2013 18:23:32 -0500 Received: from mho-04-ewr.mailhop.org ([204.13.248.74]:23774 "EHLO mho-02-ewr.mailhop.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752351Ab3AUXXa (ORCPT ); Mon, 21 Jan 2013 18:23:30 -0500 X-Mail-Handler: Dyn Standard SMTP by Dyn X-Originating-IP: 50.131.214.131 X-Report-Abuse-To: abuse@dyndns.com (see http://www.dyndns.com/services/sendlabs/outbound_abuse.html for abuse reporting information) X-MHO-User: U2FsdGVkX19UP07Sjwpl9PJjExxXiEFy Date: Mon, 21 Jan 2013 15:23:22 -0800 From: Tony Lindgren To: Russell King - ARM Linux Cc: Arnd Bergmann , Matt Sealey , Linux ARM Kernel ML , LKML , Peter Zijlstra , Ingo Molnar , John Stultz , Ben Dooks Subject: Re: One of these things (CONFIG_HZ) is not like the others.. Message-ID: <20130121232322.GK15361@atomide.com> References: <201301212041.17951.arnd@arndb.de> <20130121210341.GW23505@n2100.arm.linux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130121210341.GW23505@n2100.arm.linux.org.uk> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Russell King - ARM Linux [130121 13:07]: > > As for Samsung and the rest I can't comment. The original reason OMAP > used this though was because the 32768Hz counter can't produce 100Hz > without a .1% error - too much error under pre-clocksource > implementations for timekeeping. Whether that's changed with the > clocksource/clockevent support needs to be checked. Yes that's why HZ was originally set to 128. That value (or some multiple) still makes sense when the 32 KiHZ clock source is being used. Of course we should rely on the local timer when running for the SoCs that have them. Regards, Tony