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=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_SANE_2 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 0DE15C76191 for ; Fri, 26 Jul 2019 11:59:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E3F43218DA for ; Fri, 26 Jul 2019 11:59:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726787AbfGZL7z (ORCPT ); Fri, 26 Jul 2019 07:59:55 -0400 Received: from mailgw02.mediatek.com ([210.61.82.184]:30432 "EHLO mailgw02.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726000AbfGZL7y (ORCPT ); Fri, 26 Jul 2019 07:59:54 -0400 X-UUID: 7f884de187424569bf5cd7ef18904073-20190726 X-UUID: 7f884de187424569bf5cd7ef18904073-20190726 Received: from mtkcas08.mediatek.inc [(172.21.101.126)] by mailgw02.mediatek.com (envelope-from ) (Cellopoint E-mail Firewall v4.1.10 Build 0707 with TLS) with ESMTP id 1644991987; Fri, 26 Jul 2019 19:59:46 +0800 Received: from MTKCAS06.mediatek.inc (172.21.101.30) by mtkmbs01n1.mediatek.inc (172.21.101.68) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Fri, 26 Jul 2019 19:59:46 +0800 Received: from [172.21.84.99] (172.21.84.99) by MTKCAS06.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Fri, 26 Jul 2019 19:59:46 +0800 Message-ID: <1564142386.1212.621.camel@mtksdccf07> Subject: Re: [RFC, v3 9/9] media: platform: Add Mediatek ISP P1 shared memory device From: Jungo Lin To: Robin Murphy CC: Tomasz Figa , Christoph Hellwig , , Sean Cheng =?UTF-8?Q?=28=E9=84=AD=E6=98=87=E5=BC=98=29?= , Mauro Carvalho Chehab , Rynn Wu =?UTF-8?Q?=28=E5=90=B3=E8=82=B2=E6=81=A9=29?= , "Linux Media Mailing List" , srv_heupstream , Rob Herring , Ryan Yu =?UTF-8?Q?=28=E4=BD=99=E5=AD=9F=E4=BF=AE=29?= , Frankie Chiu =?UTF-8?Q?=28=E9=82=B1=E6=96=87=E5=87=B1=29?= , Hans Verkuil , Sj Huang , "moderated list:ARM/Mediatek SoC support" , Laurent Pinchart , , Frederic Chen =?UTF-8?Q?=28=E9=99=B3=E4=BF=8A=E5=85=83=29?= , "list@263.net:IOMMU DRIVERS" , "Joerg Roedel" , , "Matthias Brugger" Date: Fri, 26 Jul 2019 19:59:46 +0800 In-Reply-To: <4460bc91-352a-7f3a-cbed-1b95e743ca8c@arm.com> References: <20190611035344.29814-1-jungo.lin@mediatek.com> <20190611035344.29814-10-jungo.lin@mediatek.com> <20190701072532.GB137710@chromium.org> <1562297618.1212.46.camel@mtksdccf07> <1562313579.1212.73.camel@mtksdccf07> <1563870117.1212.455.camel@mtksdccf07> <20190726074116.GA19745@infradead.org> <4460bc91-352a-7f3a-cbed-1b95e743ca8c@arm.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit MIME-Version: 1.0 X-MTK: N Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Hi Robin: On Fri, 2019-07-26 at 12:04 +0100, Robin Murphy wrote: > On 26/07/2019 08:42, Tomasz Figa wrote: > > On Fri, Jul 26, 2019 at 4:41 PM Christoph Hellwig wrote: > >> > >> On Fri, Jul 26, 2019 at 02:15:14PM +0900, Tomasz Figa wrote: > >>> Could you try dma_get_sgtable() with the SCP struct device and then > >>> dma_map_sg() with the P1 struct device? > >> > >> Please don't do that. dma_get_sgtable is a pretty broken API (see > >> the common near the arm implementation) and we should not add more > >> users of it. If you want a piece of memory that can be mapped to > >> multiple devices allocate it using alloc_pages and then just map > >> it to each device. > > > > Thanks for taking a look at this thread. > > > > Unfortunately that wouldn't work. We have a specific reserved memory > > pool that is the only memory area accessible to one of the devices. > > Any idea how to handle this? > > If it's reserved in the sense of being outside struct-page-backed > "kernel memory", then provided you have a consistent CPU physical > address it might be reasonable for other devices to access it via > dma_map_resource(). > > Robin. Thank you for your suggestion. After revising to use dma_map_resource(), it is worked. Below is the current implementation. Pleas kindly help us to check if there is any misunderstanding. #define MTK_ISP_COMPOSER_MEM_SIZE 0x200000 /* * Allocate coherent reserved memory for SCP firmware usage. * The size of SCP composer's memory is fixed to 0x200000 * for the requirement of firmware. */ ptr = dma_alloc_coherent(p1_dev->cam_dev.smem_dev, MTK_ISP_COMPOSER_MEM_SIZE, &addr, GFP_KERNEL); if (!ptr) { dev_err(dev, "failed to allocate compose memory\n"); return -ENOMEM; } p1_dev->composer_scp_addr = addr; p1_dev->composer_virt_addr = ptr; dev_dbg(dev, "scp addr:%pad va:%pK\n", &addr, ptr); /* * This reserved memory is also be used by ISP P1 HW. * Need to get iova address for ISP P1 DMA. */ addr = dma_map_resource(dev, addr, MTK_ISP_COMPOSER_MEM_SIZE, DMA_BIDIRECTIONAL, DMA_ATTR_SKIP_CPU_SYNC); if (dma_mapping_error(dev, addr)) { dev_err(dev, "Failed to map scp iova\n"); ret = -ENOMEM; goto fail_free_mem; } p1_dev->composer_iova = addr; dev_info(dev, "scp iova addr:%pad\n", &addr); Moreover, appropriate Tomasz & Christoph's help on this issue. Best regards, Jungo