Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932608AbdC1XYU (ORCPT ); Tue, 28 Mar 2017 19:24:20 -0400 Received: from lelnx194.ext.ti.com ([198.47.27.80]:30601 "EHLO lelnx194.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932261AbdC1XYS (ORCPT ); Tue, 28 Mar 2017 19:24:18 -0400 Subject: Re: [RFC LINUX PATCH 0/3] Allow remote to specify shared memory To: Wendy Liang References: <1490383336-23117-1-git-send-email-jliang@xilinx.com> CC: Wendy Liang , Bjorn Andersson , , , Wendy Liang From: Suman Anna Message-ID: <3aaedbd9-168f-9dd0-62de-3e4209ee09a8@ti.com> Date: Tue, 28 Mar 2017 18:24:09 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1965 Lines: 56 Hi Wendy, On 03/28/2017 01:52 PM, Wendy Liang wrote: > Thanks Suman for your comments. > > On Mon, Mar 27, 2017 at 8:54 AM, Suman Anna wrote: >> Hi Wendy, >> >> On 03/24/2017 02:22 PM, Wendy Liang wrote: >>> This patch enables the remoteproc to specify the shared memory. >>> Remoteproc declared this memory as DMA memory. >>> It can be used for virtio, or shared buffers. >> >> You should be able to achieve this without any remoteproc core changes. >> You can do this by defining a reserved-memory node in your DTS file (can >> be a CMA pool or a DMA pool), assigning the node using memory-region in >> your remoteproc DT node and using the function, >> of_reserved_mem_device_init() in your remoteproc driver. > > The idea to introduce the rproc_mem is to let the remote to specify > the shared memory. > I am trying to see if there is a way to specify this software attribute without > touching the device tree as it doesn't look like it is hardware related. > And try to see if there is a way that when I change the firmware, i > don't need to change the device tree. So is this shared memory going to be accessed through an MMU by the remote processor? If not, don't you need a specific carveout, which would then in turn mean boot-time memory reservation? regards Suman > > Thanks, > Wendy > >> >> regards >> Suman >> >>> >>> Wendy Liang (3): >>> remoteproc: add rproc mem resource entry >>> remoteproc: add rproc_mem resource entry handler >>> remoteproc: Release DMA declare mem when cleanup rsc >>> >>> drivers/remoteproc/remoteproc_core.c | 40 ++++++++++++++++++++++++++++++++++++ >>> include/linux/remoteproc.h | 23 ++++++++++++++++++++- >>> 2 files changed, 62 insertions(+), 1 deletion(-) >>> >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-remoteproc" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html