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=-13.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 D599AC433E0 for ; Wed, 23 Dec 2020 15:12:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8D84D207A4 for ; Wed, 23 Dec 2020 15:12:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726633AbgLWPLs (ORCPT ); Wed, 23 Dec 2020 10:11:48 -0500 Received: from m43-15.mailgun.net ([69.72.43.15]:32639 "EHLO m43-15.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725267AbgLWPLr (ORCPT ); Wed, 23 Dec 2020 10:11:47 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1608736287; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=0aAZ/bMuIrvzWM9gWlmih4RGaEX1HT300DY+Q/rbUMw=; b=Cs1W0vOaOd3Igb2WuyBsr4/k+bk3Vb8KIvpRRzQVaJIoprWgzzIz7RiigLAd8cU3hjMaixwA LCzvOehqC6luX4V5Sn7hl63UMRTDObE4xUpjVsjxZEGyFnLLtMrkJjFbkBZGogXgY7wCXjPr BAWeAPcT3xvhUXIvl+NfsGiDbF4= X-Mailgun-Sending-Ip: 69.72.43.15 X-Mailgun-Sid: WyI0MWYwYSIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n06.prod.us-east-1.postgun.com with SMTP id 5fe35e02b00c0d7ad475ea3f (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Wed, 23 Dec 2020 15:10:58 GMT Sender: isaacm=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 7046EC43461; Wed, 23 Dec 2020 15:10:57 +0000 (UTC) Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: isaacm) by smtp.codeaurora.org (Postfix) with ESMTPSA id 4E4CBC433C6; Wed, 23 Dec 2020 15:10:56 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Date: Wed, 23 Dec 2020 07:10:56 -0800 From: isaacm@codeaurora.org To: Robin Murphy 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 Subject: Re: [PATCH v2 3/7] iommu/arm-smmu: Add dependency on io-pgtable format modules In-Reply-To: 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> Message-ID: X-Sender: isaacm@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-12-23 05:05, Robin Murphy wrote: > 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. > Understood, I will keep it there and reword the commit msg. I just tried it out in an environment where the io-pgtable-arm-v7s module isn't present, and I didn't see any warnings or error messages, and the SMMU driver module was loaded properly, so yes, it's good to have it. Thanks, Isaac >> 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