From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1181EC43603 for ; Tue, 17 Dec 2019 00:52:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E59BD24673 for ; Tue, 17 Dec 2019 00:52:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727697AbfLQAwk (ORCPT ); Mon, 16 Dec 2019 19:52:40 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:35558 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727209AbfLQAvq (ORCPT ); Mon, 16 Dec 2019 19:51:46 -0500 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1ih15O-0003PJ-3b; Tue, 17 Dec 2019 00:51:38 +0000 Received: from ben by deadeye with local (Exim 4.93-RC7) (envelope-from ) id 1ih15L-0005fi-CI; Tue, 17 Dec 2019 00:51:35 +0000 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Feng Tang" , "Kai-Heng Feng" , "Thomas Gleixner" Date: Tue, 17 Dec 2019 00:47:42 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 128/136] x86/quirks: Disable HPET on Intel Coffe Lake platforms In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.80-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Kai-Heng Feng commit fc5db58539b49351e76f19817ed1102bf7c712d0 upstream. Some Coffee Lake platforms have a skewed HPET timer once the SoCs entered PC10, which in consequence marks TSC as unstable because HPET is used as watchdog clocksource for TSC. Harry Pan tried to work around it in the clocksource watchdog code [1] thereby creating a circular dependency between HPET and TSC. This also ignores the fact, that HPET is not only unsuitable as watchdog clocksource on these systems, it becomes unusable in general. Disable HPET on affected platforms. Suggested-by: Feng Tang Signed-off-by: Kai-Heng Feng Signed-off-by: Thomas Gleixner Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203183 Link: https://lore.kernel.org/lkml/20190516090651.1396-1-harry.pan@intel.com/ [1] Link: https://lkml.kernel.org/r/20191016103816.30650-1-kai.heng.feng@canonical.com Signed-off-by: Ben Hutchings --- arch/x86/kernel/early-quirks.c | 2 ++ 1 file changed, 2 insertions(+) --- a/arch/x86/kernel/early-quirks.c +++ b/arch/x86/kernel/early-quirks.c @@ -672,6 +672,8 @@ static struct chipset early_qrk[] __init */ { PCI_VENDOR_ID_INTEL, 0x0f00, PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, force_disable_hpet}, + { PCI_VENDOR_ID_INTEL, 0x3ec4, + PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, force_disable_hpet}, { PCI_VENDOR_ID_BROADCOM, 0x4331, PCI_CLASS_NETWORK_OTHER, PCI_ANY_ID, 0, apple_airport_reset}, {}