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=-17.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 DDC62C47089 for ; Wed, 26 May 2021 20:58:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BA6E461157 for ; Wed, 26 May 2021 20:58:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233794AbhEZVAN (ORCPT ); Wed, 26 May 2021 17:00:13 -0400 Received: from mail.kernel.org ([198.145.29.99]:35774 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233717AbhEZVAN (ORCPT ); Wed, 26 May 2021 17:00:13 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0BAD6613D3; Wed, 26 May 2021 20:58:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1622062721; bh=tca5jhJa+R66QtoXGvrvfr4L4lN/+LgPF3bkHUwVN64=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=IqpaWP4hrBZQWfPpeX+KY4vXPCZN4tFfh2wix4raRcP8uhvW1JskteRVnDJSFw7w7 G9xVgaP4FSmFqG5AzxQdN7m1WapB4MVocpqD9PgP83oprYedT7dSjX4lqPk12UX3OR wFY20EHtmSxlfSY6/VWO5V8qW4dtBYoO2/87TwPR2V/UrKQiFsFJVRuviPLDI+jsH3 AjYcAjb5auWc8GWImmHjpS0i+JCr7ioJNd6vImI1LqVbdUrKRFhOlnSwYuQrTkj7yv dvp6lHMd3gT+RPmXAo8D5Md+hspw2yEPNoPLUvDeA+WLbMybmPv4H4p5ZY5+fA605/ EmL8gZwpaIeTw== Date: Wed, 26 May 2021 21:58:36 +0100 From: Will Deacon To: Maximilian Luz Cc: Bjorn Helgaas , lorenzo.pieralisi@arm.com, "Rafael J. Wysocki" , Len Brown , Catalin Marinas , linux-pci@vger.kernel.org, linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH] Revert "arm64: PCI: Exclude ACPI "consumer" resources from host bridge windows" Message-ID: <20210526205836.GA20320@willie-the-truck> References: <20210510234020.1330087-1-luzmaximilian@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210510234020.1330087-1-luzmaximilian@gmail.com> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Tue, May 11, 2021 at 01:40:20AM +0200, Maximilian Luz wrote: > The Microsoft Surface Pro X has host bridges defined as > > Name (_HID, EisaId ("PNP0A08") /* PCI Express Bus */) // _HID: Hardware ID > Name (_CID, EisaId ("PNP0A03") /* PCI Bus */) // _CID: Compatible ID > > Method (_CRS, 0, NotSerialized) // _CRS: Current Resource Settings > { > Name (RBUF, ResourceTemplate () > { > Memory32Fixed (ReadWrite, > 0x60200000, // Address Base > 0x01DF0000, // Address Length > ) > WordBusNumber (ResourceProducer, MinFixed, MaxFixed, PosDecode, > 0x0000, // Granularity > 0x0000, // Range Minimum > 0x0001, // Range Maximum > 0x0000, // Translation Offset > 0x0002, // Length > ,, ) > }) > Return (RBUF) /* \_SB_.PCI0._CRS.RBUF */ > } > > meaning that the memory resources aren't (explicitly) defined as > "producers", i.e. host bridge windows. > > Commit 8fd4391ee717 ("arm64: PCI: Exclude ACPI "consumer" resources from > host bridge windows") introduced a check that removes such resources, > causing BAR allocation failures later on: > > [ 0.150731] pci 0002:00:00.0: BAR 14: no space for [mem size 0x00100000] > [ 0.150744] pci 0002:00:00.0: BAR 14: failed to assign [mem size 0x00100000] > [ 0.150758] pci 0002:01:00.0: BAR 0: no space for [mem size 0x00004000 64bit] > [ 0.150769] pci 0002:01:00.0: BAR 0: failed to assign [mem size 0x00004000 64bit] > > This eventually prevents the PCIe NVME drive from being accessible. > > On x86 we already skip the check for producer/window due to some history > with negligent firmware. It seems that Microsoft is intent on continuing > that history on their ARM devices, so let's drop that check here too. > > Signed-off-by: Maximilian Luz > --- > > Please note: I am not sure if this is the right way to fix that, e.g. I > don't know if any additional checks like on IA64 or x86 might be > required instead, or if this might break things on other devices. So > please consider this more as a bug report rather than a fix. > > Apologies for the re-send, I seem to have unintentionally added a blank > line before the subject. > > --- > arch/arm64/kernel/pci.c | 14 -------------- > 1 file changed, 14 deletions(-) Adding Lorenzo to cc, as he'll have a much better idea about this than me. This is: https://lore.kernel.org/r/20210510234020.1330087-1-luzmaximilian@gmail.com Will