Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752926AbaFEWz0 (ORCPT ); Thu, 5 Jun 2014 18:55:26 -0400 Received: from avon.wwwdotorg.org ([70.85.31.133]:56509 "EHLO avon.wwwdotorg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752521AbaFEWzZ (ORCPT ); Thu, 5 Jun 2014 18:55:25 -0400 Message-ID: <5390F55A.8090207@wwwdotorg.org> Date: Thu, 05 Jun 2014 16:55:22 -0600 From: Stephen Warren User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: Peter De Schrijver CC: Russell King , Thierry Reding , Andrew Morton , Linus Walleij , Wolfram Sang , "linux-arm-kernel@lists.infradead.org" , "linux-tegra@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v7 4/5] ARM: tegra: Add efuse and apbmisc bindings References: <1401973754-19701-1-git-send-email-pdeschrijver@nvidia.com> <1401973754-19701-5-git-send-email-pdeschrijver@nvidia.com> <5390B9F3.8030108@wwwdotorg.org> <20140605221301.GQ5961@tbergstrom-lnx.Nvidia.com> In-Reply-To: <20140605221301.GQ5961@tbergstrom-lnx.Nvidia.com> X-Enigmail-Version: 1.5.2 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/05/2014 04:13 PM, Peter De Schrijver wrote: > On Thu, Jun 05, 2014 at 08:41:55PM +0200, Stephen Warren wrote: >> On 06/05/2014 07:09 AM, Peter De Schrijver wrote: >>> Add efuse and apbmisc bindings for Tegra20, Tegra30, Tegra114 and Tegra124. >> >>> diff --git a/arch/arm/boot/dts/tegra114.dtsi b/arch/arm/boot/dts/tegra114.dtsi >> >>> + apbmisc@70000800 { >>> + compatible = "nvidia,tegra114-apbmisc", "nvidia,tegra20-apbmisc"; >> >> Is the Tegra114 APBMISC register layout 100% a backwards-compatible >> superset of that in Tegra20? For both registers the code currently uses >> *and* all possible registers the code could ever use? Since the APB MISC >> is a bit of a dumping ground for random registers, that feels unlikely, >> but perhaps it's possible. > > For all I can see it is. At least for the registers the kernel is likely to > use. But that's ("At least for the registers the kernel is likely to use") not how compatible values are defined. We need to explicitly look at all the registers and actively decide that it really is compatible in order to mark it so. If we don't want to do that, it's best just to use a separate compatible value for each SoC, and add a couple more entries into the match table. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/