From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1946055AbWKJIfp (ORCPT ); Fri, 10 Nov 2006 03:35:45 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1946057AbWKJIfp (ORCPT ); Fri, 10 Nov 2006 03:35:45 -0500 Received: from mx1.suse.de ([195.135.220.2]:16091 "EHLO mx1.suse.de") by vger.kernel.org with ESMTP id S1946055AbWKJIfo (ORCPT ); Fri, 10 Nov 2006 03:35:44 -0500 To: Alan Cox Cc: linux-kernel@vger.kernel.org Subject: Re: [PATCH] HZ: 300Hz support References: <1163018557.23956.92.camel@localhost.localdomain> From: Andi Kleen Date: 10 Nov 2006 09:35:17 +0100 In-Reply-To: <1163018557.23956.92.camel@localhost.localdomain> Message-ID: User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Alan Cox writes: > Fix two things. Firstly the unit is "Hz" not "HZ". Secondly it is useful > to have 300Hz support when doing multimedia work. 250 is fine for us in > Europe but the US frame rate is 30fps (29.99 blah for pedants). 300 > gives us a tick divisible by both 25 and 30, and for interlace work 50 > and 60. It's also giving similar performance to 250Hz. > > I'd argue we should remove 250 and add 300, but that might be excess > disruption for now. If we go down that path I would like to have 256. Why? There are still lots of systems with broken Interrupt 0 routing and usually on those the RTC works just fine. But unfortunately RTC can be only programmed to power of two frequencies. 256 would fit. -Andi