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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_GIT 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 68745C468C6 for ; Thu, 19 Jul 2018 10:56:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 21DE820671 for ; Thu, 19 Jul 2018 10:56:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 21DE820671 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731754AbeGSLig (ORCPT ); Thu, 19 Jul 2018 07:38:36 -0400 Received: from foss.arm.com ([217.140.101.70]:47452 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730845AbeGSLig (ORCPT ); Thu, 19 Jul 2018 07:38:36 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0C0811682; Thu, 19 Jul 2018 03:56:00 -0700 (PDT) Received: from en101.cambridge.arm.com (en101.cambridge.arm.com [10.1.206.73]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id A99983F246; Thu, 19 Jul 2018 03:55:57 -0700 (PDT) From: Suzuki K Poulose To: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, robh@kernel.org, mathieu.poirier@linaro.org, sudeep.holla@arm.com, frowand.list@gmail.com, devicetree@vger.kernel.org, mark.rutland@arm.com, matt.sealey@arm.com, charles.garcia-tobin@arm.com, coresight@lists.linaro.org, john.horley@arm.com, mike.leach@linaro.org, Suzuki K Poulose Subject: [PATCH v2 08/10] coresight: dts: Document usage of graph bindings Date: Thu, 19 Jul 2018 11:55:12 +0100 Message-Id: <1531997715-6767-9-git-send-email-suzuki.poulose@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1531997715-6767-1-git-send-email-suzuki.poulose@arm.com> References: <1531997715-6767-1-git-send-email-suzuki.poulose@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Before we update the bindings, document the current graph bindings and usage of additional properties. Reviewed-by: Mathieu Poirier Signed-off-by: Suzuki K Poulose --- .../devicetree/bindings/arm/coresight.txt | 30 +++++++++++++++++++--- 1 file changed, 26 insertions(+), 4 deletions(-) diff --git a/Documentation/devicetree/bindings/arm/coresight.txt b/Documentation/devicetree/bindings/arm/coresight.txt index 5d1ad09..8e21512 100644 --- a/Documentation/devicetree/bindings/arm/coresight.txt +++ b/Documentation/devicetree/bindings/arm/coresight.txt @@ -54,9 +54,7 @@ its hardware characteristcs. clocks the core of that coresight component. The latter clock is optional. - * port or ports: The representation of the component's port - layout using the generic DT graph presentation found in - "bindings/graph.txt". + * port or ports: see "Graph bindings for Coresight" below. * Additional required properties for System Trace Macrocells (STM): * reg: along with the physical base address and length of the register @@ -73,7 +71,7 @@ its hardware characteristcs. AMBA markee): - "arm,coresight-replicator" - * port or ports: same as above. + * port or ports: see "Graph bindings for Coresight" below. * Optional properties for ETM/PTMs: @@ -96,6 +94,30 @@ its hardware characteristcs. * interrupts : Exactly one SPI may be listed for reporting the address error +Graph bindings for Coresight +------------------------------- + +Coresight components are interconnected to create a data path for the flow of +trace data generated from the "sources" to their collection points "sink". +Each coresight component must describe the "input" and "output" connections. +The connections must be described via generic DT graph bindings as described +by the "bindings/graph.txt", where each "port" along with an "endpoint" +component represents a hardware port and the connection. + +Since it is possible to have multiple connections for any coresight component +with a specific direction of data flow, each connection must define the +following properties to uniquely identify the connection details. + + * Direction of the data flow w.r.t the component : + Each input port must have the following property defined at the "endpoint" + for the port. + "slave-mode" + + * Hardware Port number at the component: + - The hardware port number is assumed to be the address of the "port" + component. + + Example: 1. Sinks -- 2.7.4