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=-0.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 97806C004C9 for ; Tue, 7 May 2019 15:48:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 733E221019 for ; Tue, 7 May 2019 15:48:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726582AbfEGPsW convert rfc822-to-8bit (ORCPT ); Tue, 7 May 2019 11:48:22 -0400 Received: from mx2.suse.de ([195.135.220.15]:37950 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726000AbfEGPsW (ORCPT ); Tue, 7 May 2019 11:48:22 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id ABF71AE0F; Tue, 7 May 2019 15:48:20 +0000 (UTC) Date: Tue, 7 May 2019 17:48:20 +0200 From: Thomas Bogendoerfer To: Lorenzo Pieralisi Cc: Bjorn Helgaas , Ralf Baechle , Paul Burton , James Hogan , linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org Subject: Re: [PATCH v3 00/3] MIPS: SGI-IP27 rework part2 Message-Id: <20190507174820.381fd56f678609416fd8b617@suse.de> In-Reply-To: <20190507153117.GA21665@e121166-lin.cambridge.arm.com> References: <20190319154755.31049-1-tbogendoerfer@suse.de> <20190418205726.GB126710@google.com> <20190507153117.GA21665@e121166-lin.cambridge.arm.com> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-suse-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org On Tue, 7 May 2019 16:31:17 +0100 Lorenzo Pieralisi wrote: > On Thu, Apr 18, 2019 at 03:57:26PM -0500, Bjorn Helgaas wrote: > > Hi Thomas, > > > > On Tue, Mar 19, 2019 at 04:47:49PM +0100, Thomas Bogendoerfer wrote: > > > SGI IP27 (Origin/Onyx2) and SGI IP30 (Octane) have a similair > > > architecture and share some hardware (ioc3/bridge). To share > > > the software parts this patchset reworks SGI IP27 interrupt > > > and pci bridge code. By using features Linux gained during the > > > many years since SGI IP27 code was integrated this even results > > > in code reduction and IMHO cleaner code. > > > > > > Tests have been done on a two module O200 (4 CPUs) and an > > > Origin 2000 (8 CPUs). > > > > Thanks for doing all this work! It seems like it basically converts > > some of the SGI PCI code to the structure typical of current host > > controller drivers and moves it to drivers/pci/controller, which all > > seems great to me. > > I had a look and the code is really, really MIPS specific, actually > I would be interested in understanding how many platforms it supports, > it is not even FW configurable. it's MIPS only and used in basically 3 different SGI platforms. > With hard-coded resources, includes in driver code and MIPS > specific kludges even if it does reuse some APIs shared with controller > drivers I am not 100% certain that moving it to drivers/pci/controller > buys us anything, this is really arch specific code, however we slice > it. hmm, I thought the idea of having one drivers/pci/controller directory is to have all of them in one place. > The line between what stays in arch and what goes to > drivers/pci/controller is thin but this code is definitely more on the > arch side IMHO. what makes the xgene driver different from the xtalk-bridge driver ? Ok it used DT, but it's still just for a specific type of SOCs from one vendor, isn't it ? > I do not question Thomas' effort, which I appreciate, I question > the end result and its usefulness, this series is even increasing > lines of kernel code, I would like to see the benefits. the move from arch/mips/pci to drivers/pci/controller increases lines of code by two lines. The whole patchset adds 155 lines, but also adds functionality to be able to use the driver with different platforms. Anyway I can live with not moving to drivers/pci/controller if you don't like it there. Thomas. -- SUSE Linux GmbH GF: Felix Imendörffer, Mary Higgins, Sri Rasiah HRB 21284 (AG Nürnberg)