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=-5.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 0C5FAC10F14 for ; Thu, 10 Oct 2019 12:08:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D7A1620650 for ; Thu, 10 Oct 2019 12:08:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570709307; bh=gG30qz7Sr0XSbBoYXSRW7wlLr51IxikKi2bTjRnYvxM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=LQ6ZZrhTiRkt8aZL0qUOZO7/SU7KX9AgmSHiZRGZAXPwIj0NJS5J/YE42TtQYKbVL /4fjPnsfosjFQV0PTr5gHaGX0vW6g5zwpwZgccBsDrGgivOzJWebrxZcyQL3yla1uJ FJHh2RJv0Y3UmX5Ac4COnfSYuVwrq1lLgRWq2qOc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733227AbfJJMI0 (ORCPT ); Thu, 10 Oct 2019 08:08:26 -0400 Received: from mail-pl1-f195.google.com ([209.85.214.195]:32795 "EHLO mail-pl1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728030AbfJJMI0 (ORCPT ); Thu, 10 Oct 2019 08:08:26 -0400 Received: by mail-pl1-f195.google.com with SMTP id d22so2704105pls.0 for ; Thu, 10 Oct 2019 05:08:26 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=XmMjypGytVZHffptIbRZhP/O0ewnjNlKS7p88IhR+ls=; b=tg4M40cASDHJxVNSwQo728skw0SB39/EfT0itx8fUhbPtLOJb2xNZdIS223RAVIrqB O+S8oAoEWIFxw95ntELPyWOT5+bB1i5Ylk154aFfRoPBYBYutJP2VOX7D7umntZafp4y fAKVkkZbU4D+vQvPghHk/8q76el55l5MzuEd3f2qf8Cn7GPmHOSuJlI1jssiHXLKnkw4 r0oG8uuskKUMwIPzkUrrFRGH7uBqq/W20+PKP6uK+eFeYh4XaJuQpwC+1MYyjgY99Hzn 25lmmW1AMOEabmbLv2S68XRWUFjncvpFF7+6htyBe5oVjqdDE7R0tOG7BYxchmEX/H4W CYOQ== X-Gm-Message-State: APjAAAWC7MR7WLoLaRlqtyoOkfOuLehmVg8Is4ji84ODkYFcOXSeWWf5 +5+R5tXSiIJVDtxMj3ndcS0= X-Google-Smtp-Source: APXvYqzpzoL0AKFn1v0waSbzHsnFgvNj4C76NrVCaOZPfK9UB7JpTasH3E+Y+WuIqMkFrMg1G0VvOQ== X-Received: by 2002:a17:902:7202:: with SMTP id ba2mr9226909plb.267.1570709305304; Thu, 10 Oct 2019 05:08:25 -0700 (PDT) Received: from 42.do-not-panic.com (42.do-not-panic.com. [157.230.128.187]) by smtp.gmail.com with ESMTPSA id m9sm5067222pjf.11.2019.10.10.05.08.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 10 Oct 2019 05:08:23 -0700 (PDT) Received: by 42.do-not-panic.com (Postfix, from userid 1000) id 1AED44024E; Thu, 10 Oct 2019 12:08:23 +0000 (UTC) Date: Thu, 10 Oct 2019 12:08:23 +0000 From: Luis Chamberlain To: Tuowen Zhao Cc: lee.jones@linaro.org, linux-kernel@vger.kernel.org, andriy.shevchenko@linux.intel.com, mika.westerberg@linux.intel.com, acelan.kao@canonical.com, bhelgaas@google.com, kai.heng.feng@canonical.com Subject: Re: [PATCH v3 2/2] mfd: intel-lpss: use devm_ioremap_uc for MMIO Message-ID: <20191010120823.GD16384@42.do-not-panic.com> References: <20191010030335.204974-1-ztuowen@gmail.com> <20191010030335.204974-2-ztuowen@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191010030335.204974-2-ztuowen@gmail.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 09, 2019 at 09:03:35PM -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 use devm_ioremap_uc to overwrite/ignore the MTRR settings > by forcing 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 > Tested-by: AceLan Kao > Signed-off-by: Tuowen Zhao > Acked-by: Mika Westerberg > Acked-by: Andy Shevchenko I think you'll want to Cc stable for this, as well as the last patch. LTS kernels with the ioremap_uc will be able to leverage the fix. Luis