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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 F1878C433E6 for ; Thu, 18 Feb 2021 22:53:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A3A5C64DFD for ; Thu, 18 Feb 2021 22:53:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230015AbhBRWw7 (ORCPT ); Thu, 18 Feb 2021 17:52:59 -0500 Received: from foss.arm.com ([217.140.110.172]:56576 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229990AbhBRWw4 (ORCPT ); Thu, 18 Feb 2021 17:52:56 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 791EEED1; Thu, 18 Feb 2021 14:52:05 -0800 (PST) Received: from [10.57.61.241] (unknown [10.57.61.241]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D9D4A3F73D; Thu, 18 Feb 2021 14:52:03 -0800 (PST) Subject: Re: [PATCH V3 06/14] dts: bindings: Document device tree bindings for ETE To: Rob Herring Cc: Anshuman Khandual , devicetree@vger.kernel.org, mathieu.poirier@linaro.org, coresight@lists.linaro.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, lcherian@marvell.com, mike.leach@linaro.org References: <1611737738-1493-1-git-send-email-anshuman.khandual@arm.com> <1611737738-1493-7-git-send-email-anshuman.khandual@arm.com> <20210209190031.GA4102836@robh.at.kernel.org> <4d0e6b88-72c2-be23-f43a-3f541f9ebb86@arm.com> <20210218183335.GA915713@robh.at.kernel.org> From: Suzuki K Poulose Message-ID: <952f91ef-7fd2-a3d4-06d8-b7f433aa4c76@arm.com> Date: Thu, 18 Feb 2021 22:51:56 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <20210218183335.GA915713@robh.at.kernel.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/18/21 6:33 PM, Rob Herring wrote: > On Wed, Feb 10, 2021 at 12:33:44PM +0000, Suzuki K Poulose wrote: >> Hi Rob >> >> On 2/9/21 7:00 PM, Rob Herring wrote: >>> On Wed, Jan 27, 2021 at 02:25:30PM +0530, Anshuman Khandual wrote: >>>> From: Suzuki K Poulose >>>> >>>> Document the device tree bindings for Embedded Trace Extensions. >>>> ETE can be connected to legacy coresight components and thus >>>> could optionally contain a connection graph as described by >>>> the CoreSight bindings. >>>> >>>> Cc: devicetree@vger.kernel.org >>>> Cc: Mathieu Poirier >>>> Cc: Mike Leach >>>> Cc: Rob Herring >>>> Signed-off-by: Suzuki K Poulose >>>> Signed-off-by: Anshuman Khandual >>>> --- >>>> Changes in V3: >>>> >>>> - Fixed all DT yaml semantics problems >>>> >>>> Documentation/devicetree/bindings/arm/ete.yaml | 74 ++++++++++++++++++++++++++ >>>> 1 file changed, 74 insertions(+) >>>> create mode 100644 Documentation/devicetree/bindings/arm/ete.yaml >>>> >>>> diff --git a/Documentation/devicetree/bindings/arm/ete.yaml b/Documentation/devicetree/bindings/arm/ete.yaml >>>> new file mode 100644 >>>> index 0000000..edc1fe2 >>>> --- /dev/null >>>> +++ b/Documentation/devicetree/bindings/arm/ete.yaml >>>> @@ -0,0 +1,74 @@ >>>> +# SPDX-License-Identifier: GPL-2.0-only or BSD-2-Clause >>>> +# Copyright 2021, Arm Ltd >>>> +%YAML 1.2 >>>> +--- >>>> +$id: "http://devicetree.org/schemas/arm/ete.yaml#" >>>> +$schema: "http://devicetree.org/meta-schemas/core.yaml#" >>>> + >>>> +title: ARM Embedded Trace Extensions >>>> + >>>> +maintainers: >>>> + - Suzuki K Poulose >>>> + - Mathieu Poirier >>>> + >>>> +description: | >>>> + Arm Embedded Trace Extension(ETE) is a per CPU trace component that >>>> + allows tracing the CPU execution. It overlaps with the CoreSight ETMv4 >>>> + architecture and has extended support for future architecture changes. >>>> + The trace generated by the ETE could be stored via legacy CoreSight >>>> + components (e.g, TMC-ETR) or other means (e.g, using a per CPU buffer >>>> + Arm Trace Buffer Extension (TRBE)). Since the ETE can be connected to >>>> + legacy CoreSight components, a node must be listed per instance, along >>>> + with any optional connection graph as per the coresight bindings. >>>> + See bindings/arm/coresight.txt. >>>> + >>>> +properties: >>>> + $nodename: >>>> + pattern: "^ete([0-9a-f]+)$" >>>> + compatible: >>>> + items: >>>> + - const: arm,embedded-trace-extension >>>> + >>>> + cpu: >>> >>> We've already established 'cpus' for this purpose. >>> >> >> Please see : https://lkml.kernel.org/r/9417218b-6eda-373b-a2cb-869089ffc7cd@arm.com >> for my response in the previous version to this and the one with out-ports. > > Okay, fair enough. > >> >>>> + description: | >>>> + Handle to the cpu this ETE is bound to. >>>> + $ref: /schemas/types.yaml#/definitions/phandle >>>> + >>>> + out-ports: >>>> + type: object >>> >>> Replace with: $ref: /schemas/graph.yaml#/properties/ports >> >> So, just to confirm again : >> The CoreSight graph bindings expect the input ports and output ports >> grouped under in-ports{} and out-ports{} respectively to avoid having >> to specify the direction of the ports in the individual "port" nodes. >> i.e >> >> in-ports { >> >> property: ports >> OR >> property: port >> >> required: >> OneOf: >> ports >> port > > No, 'ports' as a child of in-ports is not correct. There should only be > 'port(@[0-9a-f]+)?' nodes. That's why you need the above $ref added. The > $ref doesn't define the node name is 'ports', but what a 'ports' or > 'foo-ports' contains. Sorry, it is my bad. We don't expect ports{} under in-ports. So your suggestion is the accurate one. I will respin. > >> } >> >> out-ports { >> >> # same as above >> } >> >> So thats why I added out-ports as a new object, where the ports/port >> could be a child node. >> >> Ideally the definition of out-ports /in-ports should go to a common schema >> for CoreSight bindings, when we move to Yaml for the existing bindings, >> which will follow in a separate series, later. > > Yes, maybe, but I'm not sure something common is going to help here. > You'll still have to describe what each 'port' node does in each device > specific binding. For CoreSight components the end-point of the ports are system specific. i.e, it could be anything on the other end. There is no fixed end-point connection. e.g, ETM could be connected to a Replicator or a Funnel. Same as here above for ETE. Thus the driver must parse the endpoints and make the connection path from devices to other devices. Anyways, will come to that in a different series. I will fix the in-ports/out-ports for the next version. Thanks for your guidance. Cheers Suzuki > > Rob >