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=-8.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 7BF28C35257 for ; Mon, 21 Sep 2020 20:45:54 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 161F121BE5 for ; Mon, 21 Sep 2020 20:45:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="Ol3y6mLG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 161F121BE5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id B47E3847C3; Mon, 21 Sep 2020 20:45:53 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Pcxhdefux3pp; Mon, 21 Sep 2020 20:45:53 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by fraxinus.osuosl.org (Postfix) with ESMTP id 517C28464B; Mon, 21 Sep 2020 20:45:53 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 40CD7C0859; Mon, 21 Sep 2020 20:45:53 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists.linuxfoundation.org (Postfix) with ESMTP id E50B3C0051 for ; Mon, 21 Sep 2020 20:45:51 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id D3627861D4 for ; Mon, 21 Sep 2020 20:45:51 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Nn4C9fPi+H3F for ; Mon, 21 Sep 2020 20:45:51 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by whitealder.osuosl.org (Postfix) with ESMTPS id 6392386193 for ; Mon, 21 Sep 2020 20:45:51 +0000 (UTC) Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3014720735; Mon, 21 Sep 2020 20:45:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600721151; bh=2azUc9d8t3fHwPUNHpcYBtku3ZGS3Konwm3NpWeBUPU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Ol3y6mLGysrQgD+hsUG5Zs8QfPycb6c9FdF4neo3Yl2B/SVvlbRvPSbSEpjww+2bT uQo4nTyqiwwW8rqhc69kVyrBTohJyZSTfJKOw07y1OP8yU+hIq6ad10ko+dr9Pn/vT pBH3mLd+y9ggYldkOg61tDWF3qUa/bBauierV5Ks= Date: Mon, 21 Sep 2020 21:45:45 +0100 From: Will Deacon To: Vennila Megavannan Subject: Re: [PATCH v2] iommu/arm: Add module parameter to set msi iova address Message-ID: <20200921204545.GA3811@willie-the-truck> References: <20200914181307.117792-1-vemegava@linux.microsoft.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200914181307.117792-1-vemegava@linux.microsoft.com> User-Agent: Mutt/1.10.1 (2018-07-13) Cc: jean-philippe@linaro.org, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, tyhicks@linux.microsoft.com, srinath.mannam@broadcom.com, bcm-kernel-feedback-list@broadcom.com, robin.murphy@arm.com, linux-arm-kernel@lists.infradead.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Mon, Sep 14, 2020 at 11:13:07AM -0700, Vennila Megavannan wrote: > From: Srinath Mannam > > Add provision to change default value of MSI IOVA base to platform's > suitable IOVA using module parameter. The present hardcoded MSI IOVA base > may not be the accessible IOVA ranges of platform. > > If any platform has the limitaion to access default MSI IOVA, then it can > be changed using "arm-smmu.msi_iova_base=0xa0000000" command line argument. > > Signed-off-by: Srinath Mannam > Co-developed-by: Vennila Megavannan > Signed-off-by: Vennila Megavannan > --- > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 5 ++++- > drivers/iommu/arm/arm-smmu/arm-smmu.c | 5 ++++- > 2 files changed, 8 insertions(+), 2 deletions(-) This feels pretty fragile. Wouldn't it be better to realise that there's a region conflict with iommu_dma_get_resv_regions() and move the MSI window accordingly at runtime? Will _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu