From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161479Ab2GLRkM (ORCPT ); Thu, 12 Jul 2012 13:40:12 -0400 Received: from e31.co.us.ibm.com ([32.97.110.149]:45810 "EHLO e31.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755432Ab2GLRkK (ORCPT ); Thu, 12 Jul 2012 13:40:10 -0400 Message-ID: <4FFF0BE9.2010307@linaro.org> Date: Thu, 12 Jul 2012 10:39:53 -0700 From: John Stultz User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:13.0) Gecko/20120615 Thunderbird/13.0.1 MIME-Version: 1.0 To: Marc Zyngier CC: Linus Walleij , Deepak Saxena , Thomas Gleixner , Linus Walleij , Catalin Marinas , linux-kernel@vger.kernel.org, Arnd Bergmann , Will Deacon , Mike Turquette , Marc Zyngier Subject: Re: [PATCH 33/36] AArch64: Generic timers support References: <1341608777-12982-1-git-send-email-catalin.marinas@arm.com> <1341608777-12982-34-git-send-email-catalin.marinas@arm.com> <12a7f9b8e6d0b4dc3e3f6fcf91ad2a18@localhost> <4FFF01FD.4050005@linaro.org> <62038bf130381e2b55cedec5f3c44760@localhost> In-Reply-To: <62038bf130381e2b55cedec5f3c44760@localhost> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12071217-7282-0000-0000-00000ADCB270 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/12/2012 10:31 AM, Marc Zyngier wrote: > On Thu, 12 Jul 2012 09:57:33 -0700, John Stultz > wrote: > >> So following ia64's method is probably better then copying the 8253's >> rate if you're not concerned about tick-granularity error. > The 8253 is completely meaningless in our case (though I'm sure someone > could try and bold one on the side of an Aarch64 CPU...), so going the ia64 > way is probably best (erm... this last bit doesn't sound quite right, > doesn't it?). Sorry, the "copying the 8253's" bit didn't come out sarcastic enough. :) The best solution would be to include the actual tick-granularity, but given its not really an architecture constant (which CLOCK_TICK_RATE assumes), that probably wouldn't be appropriate. thanks -john