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=-17.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 CE096C433E6 for ; Tue, 22 Dec 2020 19:28:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 96F5223133 for ; Tue, 22 Dec 2020 19:28:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727772AbgLVT2J (ORCPT ); Tue, 22 Dec 2020 14:28:09 -0500 Received: from foss.arm.com ([217.140.110.172]:39142 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725811AbgLVT2I (ORCPT ); Tue, 22 Dec 2020 14:28:08 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C19081FB; Tue, 22 Dec 2020 11:27:22 -0800 (PST) Received: from [10.57.34.90] (unknown [10.57.34.90]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D97A93F6CF; Tue, 22 Dec 2020 11:27:20 -0800 (PST) Subject: Re: [PATCH v2 3/7] iommu/arm-smmu: Add dependency on io-pgtable format modules To: "Isaac J. Manjarres" , iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, freedreno@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org Cc: will@kernel.org, joro@8bytes.org, pdaly@codeaurora.org, pratikp@codeaurora.org, kernel-team@android.com References: <1608597876-32367-1-git-send-email-isaacm@codeaurora.org> <1608597876-32367-4-git-send-email-isaacm@codeaurora.org> From: Robin Murphy Message-ID: <3b0c191d-3fd0-73db-c1e3-4a80aa7953d7@arm.com> Date: Tue, 22 Dec 2020 19:27:18 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: <1608597876-32367-4-git-send-email-isaacm@codeaurora.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-12-22 00:44, Isaac J. Manjarres wrote: > The SMMU driver depends on the availability of the ARM LPAE and > ARM V7S io-pgtable format code to work properly. In preparation Nit: we don't really depend on v7s - we *can* use it if it's available, address constraints are suitable, and the SMMU implementation actually supports it (many don't), but we can still quite happily not use it even so. LPAE is mandatory in the architecture so that's our only hard requirement, embodied in the kconfig select. This does mean there may technically still be a corner case involving ARM_SMMU=y and IO_PGTABLE_ARM_V7S=m, but at worst it's now a runtime failure rather than a build error, so unless and until anyone demonstrates that it actually matters I don't feel particularly inclined to give it much thought. Robin. > for having the io-pgtable formats as modules, add a "pre" > dependency with MODULE_SOFTDEP() to ensure that the io-pgtable > format modules are loaded before loading the ARM SMMU driver module. > > Signed-off-by: Isaac J. Manjarres > --- > drivers/iommu/arm/arm-smmu/arm-smmu.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c > index d8c6bfd..a72649f 100644 > --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c > +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c > @@ -2351,3 +2351,4 @@ MODULE_DESCRIPTION("IOMMU API for ARM architected SMMU implementations"); > MODULE_AUTHOR("Will Deacon "); > MODULE_ALIAS("platform:arm-smmu"); > MODULE_LICENSE("GPL v2"); > +MODULE_SOFTDEP("pre: io-pgtable-arm io-pgtable-arm-v7s"); >