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=-4.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 6840EC433E3 for ; Mon, 13 Jul 2020 09:03:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 49A07206F0 for ; Mon, 13 Jul 2020 09:03:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729211AbgGMJDY (ORCPT ); Mon, 13 Jul 2020 05:03:24 -0400 Received: from mga11.intel.com ([192.55.52.93]:62216 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726360AbgGMJDY (ORCPT ); Mon, 13 Jul 2020 05:03:24 -0400 IronPort-SDR: FKCxaN1pN5/QCgaJ8gWMOclLRWVaE1NdRCtLlRgAZNJm62rJfwoFViblSllRzyPVSU20BHqdW9 ReA4+oFRFCag== X-IronPort-AV: E=McAfee;i="6000,8403,9680"; a="146613402" X-IronPort-AV: E=Sophos;i="5.75,347,1589266800"; d="scan'208";a="146613402" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Jul 2020 02:03:23 -0700 IronPort-SDR: UE4MUmNowr4zmxZPYlPAOi4ANrMT2reqcJZxqE4OVXjKiZBFqHzcmqsodXz9YrwexhAtUeGbiW qQkWxPT+XivA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,347,1589266800"; d="scan'208";a="325440370" Received: from smile.fi.intel.com (HELO smile) ([10.237.68.40]) by orsmga007.jf.intel.com with ESMTP; 13 Jul 2020 02:03:21 -0700 Received: from andy by smile with local (Exim 4.94) (envelope-from ) id 1juuMr-001ZBW-PN; Mon, 13 Jul 2020 12:03:21 +0300 Date: Mon, 13 Jul 2020 12:03:21 +0300 From: Andy Shevchenko To: "Reddy, MallikarjunaX" Cc: dmaengine@vger.kernel.org, vkoul@kernel.org, devicetree@vger.kernel.org, robh+dt@kernel.org, linux-kernel@vger.kernel.org, chuanhua.lei@linux.intel.com, cheol.yong.kim@intel.com, qi-ming.wu@intel.com, malliamireddy009@gmail.com Subject: Re: [PATCH v4 2/2] Add Intel LGM soc DMA support. Message-ID: <20200713090321.GA3703480@smile.fi.intel.com> References: <6be9b9cfbf6708fe371f280cb94cbdc9c04bdccb.1594273437.git.mallikarjunax.reddy@linux.intel.com> <20200709110914.GW3703480@smile.fi.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Mon, Jul 13, 2020 at 04:41:31PM +0800, Reddy, MallikarjunaX wrote: > On 7/9/2020 7:09 PM, Andy Shevchenko wrote: > > On Thu, Jul 09, 2020 at 02:01:06PM +0800, Amireddy Mallikarjuna reddy wrote: > > > Add DMA controller driver for Lightning Mountain(LGM) family of SoCs. > > > > > > The main function of the DMA controller is the transfer of data from/to any > > > DPlus compliant peripheral to/from the memory. A memory to memory copy > > > capability can also be configured. > > > > > > This ldma driver is used for configure the device and channnels for data > > > and control paths. > > > +#include "../virt-dma.h" > > I didn't find any evidence this driver utilizes virt-dma API in full. > > For example, there is a virt_dma_desc structure and descriptor management around it. > > Why don't you use it? > Lgm dma soc has its own hardware descriptor. > and each dma channel is associated with a peripheral, it is one to one > mapping between channel and associated peripheral. And this neither objects nor answers to my question. Hint: above mentioned structure is an abstraction of hardware descriptors for easier management in Linux kernel. -- With Best Regards, Andy Shevchenko