Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3AF6FC433F5 for ; Tue, 28 Dec 2021 09:15:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235863AbhL1JPh (ORCPT ); Tue, 28 Dec 2021 04:15:37 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:56350 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233036AbhL1JPe (ORCPT ); Tue, 28 Dec 2021 04:15:34 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 7E43C6117A; Tue, 28 Dec 2021 09:15:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 36527C36AE7; Tue, 28 Dec 2021 09:15:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1640682932; bh=GhkQipbGlKDnWFYSWHR8QJ9jDw3XiA0zWUSH0TczCbE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=dYWghGQbT+zkKYVLv1Zhab/gyFy9VpZvbxpbFRNzp3Lo5J6P/Q+Wf9wZJ3oL1Y4nF 96QRZWFgrpKChm6T6ENMeuTcDkoRMS//XW4vNdMJB4gLdNcNmX96GZTLdULruuieLb emRGzvA33ANfq1HyCg7yWlEMSY81FT51jd/pZeMOMTkwWI2S8tmDueYyTyJr7hwGcG yL5P+Au50kwMpsldooh4cVnB+oQkMDs7kWcv4culv3nNyxGHHdqsdStKVVXhf5e3AJ K3RgIP6/xYabneVHyG9NqbWuq3dYLRaZSL3QAii2RDYrapQzGorXDljBWHF9TwGY4F k139XXS0mA/xw== Date: Tue, 28 Dec 2021 10:15:16 +0100 From: Mauro Carvalho Chehab To: Greg Kroah-Hartman Cc: Niklas Schnelle , Arnd Bergmann , Bjorn Helgaas , John Garry , Nick Hu , Greentime Hu , Vincent Chen , Paul Walmsley , Palmer Dabbelt , Albert Ou , Guo Ren , Damien Le Moal , Ian Abbott , H Hartley Sweeten , Linus Walleij , Bartosz Golaszewski , Jean Delvare , Guenter Roeck , Dmitry Torokhov , Karsten Keil , Hans Verkuil , Sathya Prakash , Sreekanth Reddy , Suganath Prabu Subramani , Michael Grzeschik , "David S. Miller" , Jakub Kicinski , Jesse Brandeburg , Tony Nguyen , Kalle Valo , Jouni Malinen , "James E.J. Bottomley" , "Martin K. Petersen" , Hannes Reinecke , Kashyap Desai , Sumit Saxena , Shivasharan S , Nilesh Javali , GR-QLogic-Storage-Upstream@marvell.com, Mark Brown , Sudip Mukherjee , Teddy Wang , Forest Bond , Jiri Slaby , Wim Van Sebroeck , Jaroslav Kysela , Takashi Iwai , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-pci@vger.kernel.org, linux-riscv@lists.infradead.org, linux-csky@vger.kernel.org, linux-ide@vger.kernel.org, linux-gpio@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-i2c@vger.kernel.org, linux-input@vger.kernel.org, netdev@vger.kernel.org, linux-media@vger.kernel.org, MPT-FusionLinux.pdl@broadcom.com, linux-scsi@vger.kernel.org, intel-wired-lan@lists.osuosl.org, linux-wireless@vger.kernel.org, megaraidlinux.pdl@broadcom.com, linux-spi@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-staging@lists.linux.dev, linux-serial@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-watchdog@vger.kernel.org, alsa-devel@alsa-project.org Subject: Re: [RFC 01/32] Kconfig: introduce and depend on LEGACY_PCI Message-ID: <20211228101435.3a55b983@coco.lan> In-Reply-To: References: <20211227164317.4146918-1-schnelle@linux.ibm.com> <20211227164317.4146918-2-schnelle@linux.ibm.com> X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.30; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Tue, 28 Dec 2021 09:21:23 +0100 Greg Kroah-Hartman escreveu: > On Mon, Dec 27, 2021 at 05:42:46PM +0100, Niklas Schnelle wrote: > > --- a/drivers/pci/Kconfig > > +++ b/drivers/pci/Kconfig > > @@ -23,6 +23,17 @@ menuconfig PCI > > > > if PCI > > > > +config LEGACY_PCI > > + bool "Enable support for legacy PCI devices" > > + depends on HAVE_PCI > > + help > > + This option enables support for legacy PCI devices. This includes > > + PCI devices attached directly or via a bridge on a PCI Express bus. > > + It also includes compatibility features on PCI Express devices which > > + make use of legacy I/O spaces. This Kconfig doesn't seem what it is needed there, as this should be an arch-dependent feature, and not something that the poor user should be aware if a given architecture supports it or not. Also, the above will keep causing warnings or errors with randconfigs. Also, the "depends on HAVE_CPI" is bogus, as PCI already depends on HAVE_PCI: menuconfig PCI bool "PCI support" depends on HAVE_PCI help This option enables support for the PCI local bus, including support for PCI-X and the foundations for PCI Express support. Say 'Y' here unless you know what you are doing. So, instead, I would expect that a new HAVE_xxx option would be added at arch/*/Kconfig, like: config X86 ... select HAVE_PCI_DIRECT_IO It would also make sense to document it at Documentation/features/. > > All you really care about is the "legacy" I/O spaces here, this isn't > tied to PCI specifically at all, right? > > So why not just have a OLD_STYLE_IO config option or something like > that, to show that it's the i/o functions we care about here, not PCI at > all? > > And maybe not call it "old" or "legacy" as time constantly goes forward, > just describe it as it is, "DIRECT_IO"? Agreed. HAVE_PCI_DIRECT_IO (or something similar) seems a more appropriate name for it. Thanks, Mauro