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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6128EC433EF for ; Mon, 17 Jan 2022 09:25:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233941AbiAQJZh (ORCPT ); Mon, 17 Jan 2022 04:25:37 -0500 Received: from mx08-00178001.pphosted.com ([91.207.212.93]:55124 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S231292AbiAQJZg (ORCPT ); Mon, 17 Jan 2022 04:25:36 -0500 Received: from pps.filterd (m0046660.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.16.1.2/8.16.1.2) with ESMTP id 20H6Oeva003557; Mon, 17 Jan 2022 10:25:25 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=selector1; bh=4aF+FbveXGEATuFpjV4ru2bVr18YJoF4SWQIjjEfnys=; b=aVsDpRfviKH0uYJF+jBc0JaYQEyAdWmo0X7o+xWtJu49MI1oyhAwALQ8116s/n5T7q4t HPUvXpGj6sahFiaYyl/iCTwn0dDEBZpin3ENtkSiDoOVrtR0ySuUmsC4t8sAIrEs+LEK W/aySLWvj/G8B0jkxc997D7Eq/GUe5wGu1HFyniMwI7Tp9XwQ1+7WM547lOHhM8FEPhE GpONq+7rORNg3ci4ynl2UHPhNDm/mYq9jhB3oClh0YmRhLAf+1orQAUBc3tyMO456XU4 UzoDPdAQwSyK65QLTECgf60WeXRuexnqqbzNmDr0XRH9Liam/iV0LrRHh011jc419zSG 6w== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 3dmnse3qfc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 17 Jan 2022 10:25:25 +0100 Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id DA4E110002A; Mon, 17 Jan 2022 10:25:24 +0100 (CET) Received: from Webmail-eu.st.com (gpxdag2node5.st.com [10.75.127.69]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id D344A20E093; Mon, 17 Jan 2022 10:25:24 +0100 (CET) Received: from gnbcxd0016.gnb.st.com (10.75.127.51) by GPXDAG2NODE5.st.com (10.75.127.69) with Microsoft SMTP Server (TLS) id 15.0.1497.26; Mon, 17 Jan 2022 10:25:24 +0100 Date: Mon, 17 Jan 2022 10:25:16 +0100 From: Alain Volmat To: Amelie Delaunay CC: Vinod Koul , Maxime Coquelin , Alexandre Torgue , , , , Subject: Re: [PATCH] dmaengine: stm32-dma: set dma_device max_sg_burst Message-ID: <20220117092516.GA431169@gnbcxd0016.gnb.st.com> Mail-Followup-To: Amelie Delaunay , Vinod Koul , Maxime Coquelin , Alexandre Torgue , dmaengine@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20220117091740.11064-1-amelie.delaunay@foss.st.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20220117091740.11064-1-amelie.delaunay@foss.st.com> X-Disclaimer: ce message est personnel / this message is private X-Originating-IP: [10.75.127.51] X-ClientProxiedBy: SFHDAG2NODE3.st.com (10.75.127.6) To GPXDAG2NODE5.st.com (10.75.127.69) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.816,Hydra:6.0.425,FMLib:17.11.62.513 definitions=2022-01-17_03,2022-01-14_01,2021-12-02_01 Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org Hi, thanks Amelie. Tested-by: Alain Volmat Alain On Mon, Jan 17, 2022 at 10:17:40AM +0100, Amelie Delaunay wrote: > Some stm32-dma consumers [1] rather use dma_get_slave_caps() to get > max_sg_burst of their DMA channel as dma_get_max_seg_size() is specific to > the DMA controller. > All stm32-dma channels have the same features so, don't need to implement > device_caps ops. Let dma_get_slave_caps() relies on dma_device > configuration. > That's why this patch sets dma_device max_sg_burst to the maximum segment > size, which is the maximum of data items that can be transferred without > software intervention. > > [1] https://lore.kernel.org/lkml/20220110103739.118426-1-alain.volmat@foss.st.com/ > "media: stm32: dcmi: create a dma scatterlist based on DMA max_sg_burst value" > > Signed-off-by: Amelie Delaunay > --- > drivers/dma/stm32-dma.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/dma/stm32-dma.c b/drivers/dma/stm32-dma.c > index 83a37a6955a3..d2365fab1b7a 100644 > --- a/drivers/dma/stm32-dma.c > +++ b/drivers/dma/stm32-dma.c > @@ -1389,6 +1389,7 @@ static int stm32_dma_probe(struct platform_device *pdev) > dd->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; > dd->copy_align = DMAENGINE_ALIGN_32_BYTES; > dd->max_burst = STM32_DMA_MAX_BURST; > + dd->max_sg_burst = STM32_DMA_ALIGNED_MAX_DATA_ITEMS; > dd->descriptor_reuse = true; > dd->dev = &pdev->dev; > INIT_LIST_HEAD(&dd->channels); > -- > 2.25.1 >