Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752281Ab3IIGiu (ORCPT ); Mon, 9 Sep 2013 02:38:50 -0400 Received: from mail-ie0-f180.google.com ([209.85.223.180]:38408 "EHLO mail-ie0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751788Ab3IIGit (ORCPT ); Mon, 9 Sep 2013 02:38:49 -0400 MIME-Version: 1.0 In-Reply-To: <522A2D1B.3010508@wwwdotorg.org> References: <1378351680-14696-1-git-send-email-acourbot@nvidia.com> <1378351680-14696-2-git-send-email-acourbot@nvidia.com> <522A2D1B.3010508@wwwdotorg.org> From: Alexandre Courbot Date: Mon, 9 Sep 2013 15:38:28 +0900 Message-ID: Subject: Re: [PATCH v5 1/5] ARM: add basic Trusted Foundations support To: Stephen Warren 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" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2306 Lines: 56 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/firmware/trusted_foundations.c b/arch/arm/firmware/trusted_foundations.c > ... >> +void of_register_trusted_foundations(void) >> +{ >> + struct device_node *node; >> + struct trusted_foundations_platform_data pdata; >> + int err; >> + >> + node = of_find_compatible_node(NULL, NULL, "tl,trusted-foundations"); >> + >> + if (!node) >> + return; > > If you're going to revise this patch for the comment below, then I would > suggest removing the blank line before that if statement. Sure. > >> 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 > > 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? Alex. -- 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/