Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754672AbXEEPYr (ORCPT ); Sat, 5 May 2007 11:24:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755029AbXEEPYr (ORCPT ); Sat, 5 May 2007 11:24:47 -0400 Received: from www.osadl.org ([213.239.205.134]:42295 "EHLO mail.tglx.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752897AbXEEPYq (ORCPT ); Sat, 5 May 2007 11:24:46 -0400 Subject: Re: [PATCH] Blacklist Dell Optiplex 320 from using the HPET From: Thomas Gleixner Reply-To: tglx@linutronix.de To: john stultz Cc: Andi Kleen , Andrew Morton , "Guilherme M. Schroeder" , lkml In-Reply-To: <1178321228.6094.34.camel@localhost.localdomain> References: <1178314144.6094.7.camel@localhost.localdomain> <200705050118.34711.ak@suse.de> <1178321228.6094.34.camel@localhost.localdomain> Content-Type: text/plain Date: Sat, 05 May 2007 16:26:54 +0200 Message-Id: <1178375214.31213.13.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.6.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1642 Lines: 54 Guilherme, On Fri, 2007-05-04 at 16:27 -0700, john stultz wrote: > > Before going to hard to maintain DMI black lists we should first check > > if it's a more general problem and can't it be solved better? Most likely > > that system isn't the one with this issue and I don't want to apply > > DMI patches forever. > > We can give it a whirl, I just didn't want to add yet another "compare > with some other counter that may or may not work" check. In this case, > probably reading three times in a row and getting the same result would > be a clearly broken box. can you please undo John's patch and check whether the patch below works for you. Thanks, tglx Index: linux-2.6.21/arch/i386/kernel/hpet.c =================================================================== --- linux-2.6.21.orig/arch/i386/kernel/hpet.c +++ linux-2.6.21/arch/i386/kernel/hpet.c @@ -231,6 +231,7 @@ int __init hpet_enable(void) { unsigned long id; uint64_t hpet_freq; + cycle_t t1; u64 tmp; if (!is_hpet_capable()) @@ -278,6 +279,14 @@ int __init hpet_enable(void) /* Start the counter */ hpet_start_counter(); + /* Verify whether hpet counter works */ + t1 = hpet_read(); + udelay(50); + if (t1 == hpet_read()) { + printk(KERN_WARNING "HPET counter is defect\n"); + goto out_nohpet; + } + /* Initialize and register HPET clocksource * * hpet period is in femto seconds per cycle - 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/