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=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 AF2C0C4332F for ; Sun, 8 Sep 2019 12:07:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 85CA5218AF for ; Sun, 8 Sep 2019 12:07:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567944472; bh=FQIOzMKN32+D7EXQBVmHC45HY6/y00at8hGjE4IjboU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=CBSncycWSPFea7ptrorsxixjcIihg/iGj2k0y5nTf5ppGpbkRKFsfjLEsFlnkhL9m i1Gkog3xcbfAgm3qMx1Et1wSDMXjNC81y0N3xjKNmmYo/OxoQpO94JY7ZSFoUfpdng 9fsapEQfqKqMkooyzYwPFJmTSrA3m9JUuYnwPml4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728963AbfIHMHw (ORCPT ); Sun, 8 Sep 2019 08:07:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:38886 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728667AbfIHMHv (ORCPT ); Sun, 8 Sep 2019 08:07:51 -0400 Received: from localhost (unknown [122.182.221.179]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 61E13218AC; Sun, 8 Sep 2019 12:07:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567944470; bh=FQIOzMKN32+D7EXQBVmHC45HY6/y00at8hGjE4IjboU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=hj/S8W0Iw2hthBawZ0Uqi9DFTpTMB0Do4oHMemh6k/LXiFOcQ9x5LM3RWgJD4OU94 kf0+kE+gyDCgsb9mbppiRJUabFKuyu95v1ag1Ik+2cdyrdeT+gUxYgLrwa1sWoYTxK ZWaShKc+sdLCZuZXVa6oBWesMWrw6X7e5elNOg6E= Date: Sun, 8 Sep 2019 17:36:42 +0530 From: Vinod Koul To: Peter Ujfalusi Cc: robh+dt@kernel.org, dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, dan.j.williams@intel.com, devicetree@vger.kernel.org Subject: Re: [RFC 1/3] dt-bindings: dma: Add documentation for DMA domains Message-ID: <20190908120642.GK2672@vkoul-mobl> References: <20190906141816.24095-1-peter.ujfalusi@ti.com> <20190906141816.24095-2-peter.ujfalusi@ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190906141816.24095-2-peter.ujfalusi@ti.com> User-Agent: Mutt/1.12.0 (2019-05-25) Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org On 06-09-19, 17:18, Peter Ujfalusi wrote: > On systems where multiple DMA controllers available, none Slave (for example On systems with multiple DMA controllers, non Slave... > memcpy operation) users can not be described in DT as there is no device > involved from the DMA controller's point of view, DMA binding is not usable. > However in these systems still a peripheral might need to be serviced by or > it is better to serviced by specific DMA controller. > When a memcpy is used to/from a memory mapped region for example a DMA in the > same domain can perform better. > For generic software modules doing mem 2 mem operations it also matter that > they will get a channel from a controller which is faster in DDR to DDR mode > rather then from the first controller happen to be loaded. > > This property is inherited, so it may be specified in a device node or in any > of its parent nodes. > > Signed-off-by: Peter Ujfalusi > --- > .../devicetree/bindings/dma/dma-domain.yaml | 59 +++++++++++++++++++ > 1 file changed, 59 insertions(+) > create mode 100644 Documentation/devicetree/bindings/dma/dma-domain.yaml > > diff --git a/Documentation/devicetree/bindings/dma/dma-domain.yaml b/Documentation/devicetree/bindings/dma/dma-domain.yaml > new file mode 100644 > index 000000000000..c2f182f30081 > --- /dev/null > +++ b/Documentation/devicetree/bindings/dma/dma-domain.yaml > @@ -0,0 +1,59 @@ > +# SPDX-License-Identifier: GPL-2.0 > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/dma/dma-controller.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: DMA Domain Controller Definition > + > +maintainers: > + - Vinod Koul > + > +allOf: > + - $ref: "dma-controller.yaml#" > + > +description: > + On systems where multiple DMA controllers available, none Slave (for example > + memcpy operation) users can not be described in DT as there is no device > + involved from the DMA controller's point of view, DMA binding is not usable. > + However in these systems still a peripheral might need to be serviced by or > + it is better to serviced by specific DMA controller. > + When a memcpy is used to/from a memory mapped region for example a DMA in the > + same domain can perform better. > + For generic software modules doing mem 2 mem operations it also matter that > + they will get a channel from a controller which is faster in DDR to DDR mode > + rather then from the first controller happen to be loaded. > + > + This property is inherited, so it may be specified in a device node or in any > + of its parent nodes. > + > +properties: > + $dma-domain-controller: > + $ref: /schemas/types.yaml#definitions/phandle > + description: > + phande to the DMA controller node which should be used for the device or > + domain. > + > +examples: > + - | > + / { > + model = "Texas Instruments K3 AM654 SoC"; > + compatible = "ti,am654"; > + interrupt-parent = <&gic500>; > + /* For modules without device, DDR to DDR is faster on main UDMAP */ > + dma-domain-controller = <&main_udmap>; > + #address-cells = <2>; > + #size-cells = <2>; > + ... > + }; > + > + &cbass_main { > + /* For modules within MAIN domain, use main UDMAP */ > + dma-domain-controller = <&main_udmap>; > + }; > + > + &cbass_mcu { > + /* For modules within MCU domain, use mcu UDMAP */ > + dma-domain-controller = <&mcu_udmap>; perhaps add the example of main_udmap and mcu_udmap as well > + }; > +... > -- > Peter > > Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. > Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki -- ~Vinod