From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753381AbaENV0T (ORCPT ); Wed, 14 May 2014 17:26:19 -0400 Received: from smtp.codeaurora.org ([198.145.11.231]:34257 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753167AbaENV0P (ORCPT ); Wed, 14 May 2014 17:26:15 -0400 Date: Wed, 14 May 2014 14:26:12 -0700 From: Stephen Boyd To: Maxime Ripard Cc: Matthias Brugger , linux-kernel@vger.kernel.org, robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, rdunlap@infradead.org, linux@arm.linux.org.uk, daniel.lezcano@linaro.org, tglx@linutronix.de, thierry.reding@gmail.com, florian.vaussard@epfl.ch, jic23@kernel.org, jason@lakedaemon.net, andrew@lunn.ch, silvio.fricke@gmail.com, heiko.stuebner@bq.com, olof@lixom.net, sebastian.hesselbarth@gmail.com, gregory.clement@free-electrons.com, arnd@arndb.de, robherring2@gmail.com, marc.zyngier@arm.com, devicetree@vger.kernel.org, linux-doc@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v3 4/6] arm: add basic support for Mediatek MT6589 boards Message-ID: <20140514212612.GK20486@codeaurora.org> References: <1399938570-11356-1-git-send-email-matthias.bgg@gmail.com> <1399938570-11356-5-git-send-email-matthias.bgg@gmail.com> <20140513224732.GJ20486@codeaurora.org> <20140514070038.GG29258@lukather> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140514070038.GG29258@lukather> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/14, Maxime Ripard wrote: > On Tue, May 13, 2014 at 03:47:32PM -0700, Stephen Boyd wrote: > > On 05/13, Matthias Brugger wrote: > > > + "mediatek,mt6589", > > > + NULL, > > > +}; > > > + > > > +DT_MACHINE_START(MEDIATEK_DT, "Mediatek Cortex-A7 (Device Tree)") > > > + .dt_compat = mediatek_board_dt_compat, > > > +MACHINE_END > > > > You shouldn't need this file at all if the platform is part of > > the multi-platform kernel. > > From a technical point of view, you don't. But it's interesting to > keep it mostly for two things: > - You get to see the platform name in /proc/cpuinfo > - If you ever need to add platform quirks, it's already there > > We had a similar discussion two weeks ago for mach-sunxi with Olof and > Arnd, and ended up keeping this minimal machine. > It looks like it's only useful to make /proc/cpuinfo have the platform name because it really isn't that hard to add this file if we need to add platform quirks. The downside is we have to keep adding compatibles when we support new SoCs. This all leads back to the patch from Rob that removes the .name field from the DT based machine descriptor[1]. I'm not sure that thread ever resolved but it looked like a step in the right direction. At least it matches what arm64 (and what looks like mips) are doing. The concern there was finding which machine descriptor was used for the init path. Perhaps we should only use of_flat_dt_get_machine_name() for the generic machine descriptor so platforms that are using their own machine descriptor get their .name field printed and they know that their descriptor was used (assuming the .name field is unique) but the platforms using the generic descriptor would get more meaningful information and we wouldn't need to have these skeleton machine descriptors. [1] http://thread.gmane.org/gmane.linux.ports.arm.kernel/277536 -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation