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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=ham 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 79B0AC4360C for ; Tue, 8 Oct 2019 09:18:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 491B7206C2 for ; Tue, 8 Oct 2019 09:18:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730041AbfJHJSI (ORCPT ); Tue, 8 Oct 2019 05:18:08 -0400 Received: from mga05.intel.com ([192.55.52.43]:9232 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729624AbfJHJSI (ORCPT ); Tue, 8 Oct 2019 05:18:08 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 08 Oct 2019 02:18:07 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.67,270,1566889200"; d="scan'208";a="206604806" Received: from lahna.fi.intel.com (HELO lahna) ([10.237.72.157]) by fmsmga001.fm.intel.com with SMTP; 08 Oct 2019 02:18:04 -0700 Received: by lahna (sSMTP sendmail emulation); Tue, 08 Oct 2019 12:18:04 +0300 Date: Tue, 8 Oct 2019 12:18:04 +0300 From: Mika Westerberg To: Tuowen Zhao Cc: lee.jones@linaro.org, linux-kernel@vger.kernel.org, andriy.shevchenko@linux.intel.com, acelan.kao@canonical.com, bhelgaas@google.com, kai.heng.feng@canonical.com, mcgrof@kernel.org Subject: Re: [PATCH v2] mfd: intel-lpss: use devm_ioremap_uc for MMIO Message-ID: <20191008091804.GB2819@lahna.fi.intel.com> References: <20191007184231.13256-1-ztuowen@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191007184231.13256-1-ztuowen@gmail.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 07, 2019 at 12:42:31PM -0600, Tuowen Zhao wrote: > Some BIOS erroneously specifies write-combining BAR for intel-lpss-pci > in MTRR. This will cause the system to hang during boot. If possible, > this bug could be corrected with a firmware update. > > This patch adds devm_ioremap_uc as a new managed wrapper to ioremap_uc > and with it overwrite the MTRR settings to force the use of strongly > uncachable pages for intel-lpss. > > The BIOS bug is present on Dell XPS 13 7390 2-in-1: > > [ 0.001734] 5 base 4000000000 mask 6000000000 write-combining > > 4000000000-7fffffffff : PCI Bus 0000:00 > 4000000000-400fffffff : 0000:00:02.0 (i915) > 4010000000-4010000fff : 0000:00:15.0 (intel-lpss-pci) > > Link: https://bugzilla.kernel.org/show_bug.cgi?id=203485 > Signed-off-by: Tuowen Zhao Acked-by: Mika Westerberg