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 6E4A9C433E6 for ; Wed, 23 Dec 2020 13:06:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 46B7722482 for ; Wed, 23 Dec 2020 13:06:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728710AbgLWNGQ (ORCPT ); Wed, 23 Dec 2020 08:06:16 -0500 Received: from foss.arm.com ([217.140.110.172]:49954 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728649AbgLWNGQ (ORCPT ); Wed, 23 Dec 2020 08:06:16 -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 5D5B330E; Wed, 23 Dec 2020 05:05:30 -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 7B1333F66E; Wed, 23 Dec 2020 05:05:28 -0800 (PST) Subject: Re: [PATCH v2 3/7] iommu/arm-smmu: Add dependency on io-pgtable format modules To: isaacm@codeaurora.org Cc: 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, pratikp@codeaurora.org, joro@8bytes.org, kernel-team@android.com, will@kernel.org, pdaly@codeaurora.org References: <1608597876-32367-1-git-send-email-isaacm@codeaurora.org> <1608597876-32367-4-git-send-email-isaacm@codeaurora.org> <3b0c191d-3fd0-73db-c1e3-4a80aa7953d7@arm.com> From: Robin Murphy Message-ID: Date: Wed, 23 Dec 2020 13:05:25 +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: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-12-22 19:49, isaacm@codeaurora.org wrote: > On 2020-12-22 11:27, Robin Murphy wrote: >> 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. >> > Okay, I'll fix up the commit message, as well as the code, so that it > only depends on io-pgtable-arm. Well, IIUC it would make sense to keep the softdep for when the v7s module *is* present; I just wanted to clarify that it's more of a nice-to-have rather than a necessity. Robin. > Thanks, > Isaac >>> 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"); >>> >> >> _______________________________________________ >> linux-arm-kernel mailing list >> linux-arm-kernel@lists.infradead.org >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel