Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754340Ab3IIP71 (ORCPT ); Mon, 9 Sep 2013 11:59:27 -0400 Received: from avon.wwwdotorg.org ([70.85.31.133]:33622 "EHLO avon.wwwdotorg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754067Ab3IIP7Z (ORCPT ); Mon, 9 Sep 2013 11:59:25 -0400 Message-ID: <522DF058.8020509@wwwdotorg.org> Date: Mon, 09 Sep 2013 09:59:20 -0600 From: Stephen Warren User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130803 Thunderbird/17.0.8 MIME-Version: 1.0 To: Alexandre Courbot CC: Alexandre Courbot , Russell King , Tomasz Figa , Dave Martin , Olof Johansson , Arnd Bergmann , Kevin Hilman , devicetree@vger.kernel.org, Linux Kernel Mailing List , "linux-tegra@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" Subject: Re: [PATCH v5 1/5] ARM: add basic Trusted Foundations support References: <1378351680-14696-1-git-send-email-acourbot@nvidia.com> <1378351680-14696-2-git-send-email-acourbot@nvidia.com> <522A2D1B.3010508@wwwdotorg.org> In-Reply-To: X-Enigmail-Version: 1.4.6 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2262 Lines: 46 On 09/09/2013 12:38 AM, Alexandre Courbot wrote: > On Sat, Sep 7, 2013 at 4:29 AM, Stephen Warren wrote: >> On 09/04/2013 09:27 PM, Alexandre Courbot wrote: >>> Trusted Foundations is a TrustZone-based secure monitor for ARM that >>> can be invoked using a consistent SMC-based API on all supported >>> platforms. This patch adds initial basic support for Trusted >>> Foundations using the ARM firmware API. Current features are limited >>> to the ability to boot secondary processors. >>> diff --git a/arch/arm/include/asm/trusted_foundations.h b/arch/arm/include/asm/trusted_foundations.h >> >> Do we need to add the following here: >> >> #if !IS_ENABLED(CONFIG_OF) >> static inline void register_trusted_foundations(...) {} >> #endif Uggh. I meant to write **of_**register_trusted_foundations() there. >> So that there is a dummy no-op function for the non-DT-support case? I >> guess Tegra always has CONFIG_OF enabled so that call from >> mach-tegra/common.c in patch 2 will never be an issue, but perhaps it >> might if anyone else uses this? > > My expectation is that register_trusted_foundations() is called by the > platform code once it has established (through whatever mean it likes) > that Trusted Foundations is required. For platforms supporting DT, > of_register_trusted_foundations() takes care of that. Platforms that > don't support DT need another way to decide whether they *need* TF or > not. Once a platform decided that it needs TF, its absence is not an > option, and therefore I'd think that register_trusted_foundations() > should hard-fail if support is not compiled in. Or maybe I missed your > point? So yes, you missed my point, but it was my fault:-) Most of_* can be called irrespective of CONFIG_OF, and since of_register_trusted_foundations() is meant to handle internally the "do I need to do anything" case, I think it makes sense to be allowed to call it unconditionally without determining anything about either CONFIG_OF or TF DT node presence? -- 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/