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=-2.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 CB3D1C3A59E for ; Mon, 2 Sep 2019 13:00:24 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 9D9F8217F4 for ; Mon, 2 Sep 2019 13:00:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="MVyK9A7E" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9D9F8217F4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=HK9scqyYq82vh4mj4cYVv3oPOZibMzbeGdU12CwFVfg=; b=MVyK9A7EkTkdlK/RIhYIG9PmQ UtSotl+fXt9+F3vAWVXP+GLL3CwpNkglxb2ltb8YOt9LeXM4VWDWxbLOmnKeJKU1Q8OCYDsu6ORrb 6i2zEen15ZWcEZJMgayvCKAe1qn45RdbU87jeFPgmXcgKrzOoPrWnAC6NeBMYFsijzszrL2fF9HGs x4LcKRgxm8IwxCkoFsl32SHK1uZzdhhZonkdRBGSGVZZYPwSM8h/UWhUY7kMQtfFqEV2bI9UpTud/ 2eHwn+HMRriDuEIdXfEstRaC3Fc0NMuFN797ZNdPAwYCEL5DgplbKadU0c/0Ynwjd1izDtYndD+FX 7qws7n+hQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1i4lwO-0007pI-7c; Mon, 02 Sep 2019 13:00:16 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1i4lwL-0007oG-9q for linux-arm-kernel@lists.infradead.org; Mon, 02 Sep 2019 13:00:14 +0000 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 B4399337; Mon, 2 Sep 2019 06:00:10 -0700 (PDT) Received: from [10.1.197.57] (e110467-lin.cambridge.arm.com [10.1.197.57]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id BE5DD3F246; Mon, 2 Sep 2019 06:00:08 -0700 (PDT) Subject: Re: [PATCH 3/7] iommu/arm-smmu: Add tlb_sync implementation hook To: Krishna Reddy References: <1567118827-26358-1-git-send-email-vdumpa@nvidia.com> <1567118827-26358-4-git-send-email-vdumpa@nvidia.com> <554f8de1-1638-4eb9-59ae-8e1f0d786c44@arm.com> From: Robin Murphy Message-ID: <3d734164-51c9-3465-cddd-276093389797@arm.com> Date: Mon, 2 Sep 2019 14:00:07 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: Content-Language: en-GB X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190902_060013_394362_CE4DFFE2 X-CRM114-Status: GOOD ( 17.66 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Timo Alho , Thierry Reding , Mikko Perttunen , "linux-kernel@vger.kernel.org" , "joro@8bytes.org" , "will.deacon@arm.com" , "iommu@lists.linux-foundation.org" , Pritesh Raithatha , "Thomas Zeng \(SW-TEGRA\)" , Sachin Nikam , "linux-tegra@vger.kernel.org" , Yu-Huan Hsu , Juha Tukkinen , Alexander Van Brunt , "linux-arm-kernel@lists.infradead.org" Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 30/08/2019 23:49, Krishna Reddy wrote: >>> + if (smmu->impl->tlb_sync) { >>> + smmu->impl->tlb_sync(smmu, page, sync, status); > >> What I'd hoped is that rather than needing a hook for this, you could just override smmu_domain->tlb_ops from .init_context to wire up the alternate .sync method directly. That would save this extra level of indirection. > > Hi Robin, overriding tlb_ops->tlb_sync function is not enough here. > There are direct references to arm_smmu_tlb_sync_context(), arm_smmu_tlb_sync_global() functions. > In arm-smmu.c. we can replace these direct references with tlb_ops->tlb_sync() function except in one function arm_smmu_device_reset(). > When arm_smmu_device_reset() gets called, domains are not initialized and tlb_ops is not available. > Should we add a new hook for arm_smmu_tlb_sync_global() or make this as a responsibility of impl->reset() hook as it gets > called at the same place? Ah, right, I'd forgotten about the TLB maintenance on reset. Looking again, though, I think you might need to implement impl->reset anyway for the sake of clearing GFSR correctly - since the value read from the base instance technically may not match whatever bits might happen to be set in the other instances - so I don't see any issue with just calling nsmmu_tlb_sync() from there as well. Robin. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel