Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754640AbaJ1PPy (ORCPT ); Tue, 28 Oct 2014 11:15:54 -0400 Received: from www.linutronix.de ([62.245.132.108]:49263 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750925AbaJ1PPx (ORCPT ); Tue, 28 Oct 2014 11:15:53 -0400 Date: Tue, 28 Oct 2014 16:15:48 +0100 (CET) From: Thomas Gleixner To: Ley Foon Tan cc: Arnd Bergmann , Linux-Arch , "linux-kernel@vger.kernel.org" , "linux-doc@vger.kernel.org" , Chung-Lin Tang Subject: Re: [PATCH v5 21/29] nios2: Time keeping In-Reply-To: <1414492984.2295.8.camel@leyfoon-vm> Message-ID: References: <1414139071-3818-1-git-send-email-lftan@altera.com> <1806277.3CF96bVORX@wuerfel> <1414492984.2295.8.camel@leyfoon-vm> User-Agent: Alpine 2.11 (DEB 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001,URIBL_BLOCKED=0.001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 28 Oct 2014, Ley Foon Tan wrote: > On Sel, 2014-10-28 at 10:23 +0100, Arnd Bergmann wrote: > > On Tuesday 28 October 2014 10:46:29 Ley Foon Tan wrote: > > > On Sun, Oct 26, 2014 at 5:10 AM, Thomas Gleixner wrote: > > > > On Fri, 24 Oct 2014, Ley Foon Tan wrote: > > > >> +#ifndef _ASM_NIOS2_TIMEX_H > > > >> +#define _ASM_NIOS2_TIMEX_H > > > >> + > > > >> +typedef unsigned long cycles_t; > > > >> + > > > >> +extern cycles_t get_cycles(void); > > > >> + > > > >> +#define ARCH_HAS_READ_CURRENT_TIMER > > > > > > > > Why does NIOS need that? Does it have a hardware implementation > > > > dependent clock frequency which needs to be calibrated at boot time? > > > This is suggestion from Arnd to use read_current_timer instead of using > > > expensive delay loop calibration during boot. > > > > My mistake, sorry. I think the right way is to define > > calibrate_delay_is_known() rather than read_current_timer(), I was > > getting confused by the ARM implementation that does both. > Hi Arnd, > No problem, I can change that. But, seem that we don't need to have > calibrate_delay_is_known() as well. We can just set "lpj_fine" variable, > arm64 uses this. Please do so and resend the result so I can have another look and add my reviewed tag then. Thanks, tglx -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/