Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932423AbVLIT4a (ORCPT ); Fri, 9 Dec 2005 14:56:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932424AbVLIT4a (ORCPT ); Fri, 9 Dec 2005 14:56:30 -0500 Received: from natblindhugh.rzone.de ([81.169.145.175]:8367 "EHLO natblindhugh.rzone.de") by vger.kernel.org with ESMTP id S932423AbVLIT4a (ORCPT ); Fri, 9 Dec 2005 14:56:30 -0500 Subject: Re: [PATCH] x86_64: Display HPET timer option From: Erwin Rol To: Andi Kleen Cc: Linux Kernel In-Reply-To: <20051201211848.GE997@wotan.suse.de> References: <20051201204339.GC997@wotan.suse.de> <1133471197.3604.3.camel@xpc.home.erwinrol.com> <20051201211848.GE997@wotan.suse.de> Content-Type: text/plain Date: Fri, 09 Dec 2005 20:56:17 +0100 Message-Id: <1134158178.3686.2.camel@xpc.home.erwinrol.com> Mime-Version: 1.0 X-Mailer: Evolution 2.5.2 (2.5.2-1) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2053 Lines: 61 Hey Andi, I looked a bit better at what happens (by adding a bunch of printk's in drivers/char/hpet.c) and it seems that read_counter(&hpet->hpet_mc); always returns -1 and that causes the following loop in static unsigned long hpet_calibrate(struct hpets *hpetp) to endlessly loop while having local_irq_save(flags). do { m = read_counter(&hpet->hpet_mc); write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare); } while (i++, (m - start) < count); count is 0xe9 and start and (m - start) is 0. What could be the reason that read_counter(&hpet->hpet_mc) is and stays -1 ? - Erwin On Thu, 2005-12-01 at 22:18 +0100, Andi Kleen wrote: > On Thu, Dec 01, 2005 at 10:06:37PM +0100, Erwin Rol wrote: > > On Thu, 2005-12-01 at 21:43 +0100, Andi Kleen wrote: > > > On Thu, Dec 01, 2005 at 12:30:03PM -0800, Zwane Mwaikambo wrote: > > > > On Thu, 1 Dec 2005, Linus Torvalds wrote: > > > > > > > > > On Thu, 1 Dec 2005, Zwane Mwaikambo wrote: > > > > > > > > > > > > Currently the HPET timer option isn't visible in menuconfig. > > > > > > > > > > Do you want it to? > > > > > > > > > > Why would you ever compile it out? > > > > > > > > For timer testing purposes i sometimes would like not to use the HPET. > > > > Would a runtime switch be preferred? > > > > > > nohpet already exists. > > > > > > > And luckily it does cause without "nohpet" i can't boot my shuttle > > ST20G5, the NMI watchdog kills it because ti hangs when initializing the > > hpet. If the nmi watchdog is off it just hangs for ever. > > Can you give details on the machine? lspci, dmidecode, acpidmp output, > boot log from the hang case? > > Then perhaps it can be blacklisted or the failure otherwise avoided. > > [Looks like I finally need to add DMI decode support to x86-64 too :-/] > > -Andi > > - 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/