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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 3CFE9C18E5B for ; Tue, 10 Mar 2020 11:23:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1E61C24692 for ; Tue, 10 Mar 2020 11:23:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726415AbgCJLXf (ORCPT ); Tue, 10 Mar 2020 07:23:35 -0400 Received: from 8bytes.org ([81.169.241.247]:50822 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725937AbgCJLXf (ORCPT ); Tue, 10 Mar 2020 07:23:35 -0400 Received: by theia.8bytes.org (Postfix, from userid 1000) id A6D8F364; Tue, 10 Mar 2020 12:23:33 +0100 (CET) Date: Tue, 10 Mar 2020 12:23:32 +0100 From: Joerg Roedel To: Sibi Sankar Cc: bjorn.andersson@linaro.org, robh+dt@kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-msm@vger.kernel.org, iommu@lists.linux-foundation.org, linux-remoteproc@vger.kernel.org, ohad@wizery.com, agross@kernel.org Subject: Re: [PATCH 0/3] Request direct mapping for modem firmware subdevice Message-ID: <20200310112332.GG3794@8bytes.org> References: <20200309182255.20142-1-sibis@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200309182255.20142-1-sibis@codeaurora.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 09, 2020 at 11:52:52PM +0530, Sibi Sankar wrote: > The Q6 modem sub-system has direct access to DDR through memnoc and > an indirect access routed through a SMMU which MSS CE (crypto engine > sub-component of MSS) uses during out of reset sequence. Request direct > mapping for the modem-firmware subdevice since smmu is not expected > to provide access control/translation for these SIDs (sandboxing of the > modem is achieved through XPUs engaged using SMC calls). So the DMA accesses are initiated by the firmware and need to be direct mapped? Which memory region do they access? Regards, Joerg