From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752033AbeFANRI (ORCPT ); Fri, 1 Jun 2018 09:17:08 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:51844 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751617AbeFANQy (ORCPT ); Fri, 1 Jun 2018 09:16:54 -0400 From: Suzuki K Poulose To: linux-arm-kernel@lists.infradead.org Cc: mathieu.poirier@linaro.org, sudeep.holla@arm.com, robh@kernel.org, mark.rutland@arm.com, frowand.list@gmail.com, matt.sealey@arm.com, charles.garcia-tobin@arm.com, john.horley@arm.com, mike.leach@linaro.org, coresight@lists.linaro.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Suzuki K Poulose Subject: [RFC PATCH 1/8] dts: binding: coresight: Document graph bindings Date: Fri, 1 Jun 2018 14:16:00 +0100 Message-Id: <1527858967-16047-2-git-send-email-suzuki.poulose@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1527858967-16047-1-git-send-email-suzuki.poulose@arm.com> References: <1527858967-16047-1-git-send-email-suzuki.poulose@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Before we updat the bindings, document the current graph bindings and usage of additional properties. Cc: Mathieu Poirier Signed-off-by: Suzuki K Poulose --- .../devicetree/bindings/arm/coresight.txt | 28 ++++++++++++++++++---- 1 file changed, 24 insertions(+), 4 deletions(-) diff --git a/Documentation/devicetree/bindings/arm/coresight.txt b/Documentation/devicetree/bindings/arm/coresight.txt index 15ac8e8..bd36e40 100644 --- a/Documentation/devicetree/bindings/arm/coresight.txt +++ b/Documentation/devicetree/bindings/arm/coresight.txt @@ -52,9 +52,7 @@ 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 @@ -71,7 +69,7 @@ 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: @@ -86,6 +84,28 @@ its hardware characteristcs. * arm,buffer-size: size of contiguous buffer space for TMC ETR (embedded trace router) +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: -- 2.7.4 From mboxrd@z Thu Jan 1 00:00:00 1970 From: suzuki.poulose@arm.com (Suzuki K Poulose) Date: Fri, 1 Jun 2018 14:16:00 +0100 Subject: [RFC PATCH 1/8] dts: binding: coresight: Document graph bindings In-Reply-To: <1527858967-16047-1-git-send-email-suzuki.poulose@arm.com> References: <1527858967-16047-1-git-send-email-suzuki.poulose@arm.com> Message-ID: <1527858967-16047-2-git-send-email-suzuki.poulose@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Before we updat the bindings, document the current graph bindings and usage of additional properties. Cc: Mathieu Poirier Signed-off-by: Suzuki K Poulose --- .../devicetree/bindings/arm/coresight.txt | 28 ++++++++++++++++++---- 1 file changed, 24 insertions(+), 4 deletions(-) diff --git a/Documentation/devicetree/bindings/arm/coresight.txt b/Documentation/devicetree/bindings/arm/coresight.txt index 15ac8e8..bd36e40 100644 --- a/Documentation/devicetree/bindings/arm/coresight.txt +++ b/Documentation/devicetree/bindings/arm/coresight.txt @@ -52,9 +52,7 @@ 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 @@ -71,7 +69,7 @@ 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: @@ -86,6 +84,28 @@ its hardware characteristcs. * arm,buffer-size: size of contiguous buffer space for TMC ETR (embedded trace router) +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: -- 2.7.4