From nobody Wed Feb 5 18:03:09 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8CF9FC7EE43 for ; Fri, 26 May 2023 10:09:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243274AbjEZKJx (ORCPT ); Fri, 26 May 2023 06:09:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56328 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243223AbjEZKJo (ORCPT ); Fri, 26 May 2023 06:09:44 -0400 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 585B5E7; Fri, 26 May 2023 03:09:42 -0700 (PDT) Received: from pps.filterd (m0279863.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 34Q9c4L3002992; Fri, 26 May 2023 10:09:28 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=qcppdkim1; bh=927t+Jc3BbVATY+uT8tywu3mTWnUFfdwEVcCWZY9YDk=; b=WA2UKZgAnSUcjgtf88laz+SxYLmgl4Ziu4QMmrgPsctbnlpR34PhW9kY/qeSBrfCfIJt 79YZRfcFSnGa5uhtFwQxqOKdg7PTMPtly4+G3RyUDyxkBB9xauMNppEZ9ttv7B3W8F8b OjAKRtkoC87lqlvu5oIkEQHxZApJQsCAa7Ld+qIniZ7CXfqZU69PdstlkKO6AAYeETai XZjlkNjK8XdGJg8zeGLj81vuF1gugNZRaR6EBKatmPFJMlepE+cEsi3AaxEGbQZzG+86 +rywbzuNtegLtH9K+uSKAmFk7sd534NSJFKdi9VOXxhLKInXYQbauPrtyIr5sqRBAnyU DA== Received: from nasanppmta05.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3qt27n35br-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 26 May 2023 10:09:28 +0000 Received: from nasanex01a.na.qualcomm.com (nasanex01a.na.qualcomm.com [10.52.223.231]) by NASANPPMTA05.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 34QA9ITk001304 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 26 May 2023 10:09:18 GMT Received: from hazha-gv.qualcomm.com (10.80.80.8) by nasanex01a.na.qualcomm.com (10.52.223.231) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.42; Fri, 26 May 2023 03:09:12 -0700 From: Hao Zhang To: Suzuki K Poulose , Mike Leach , Leo Yan , James Clark , Alexander Shishkin , Mathieu Poirier , Konrad Dybcio , "Rob Herring" , Krzysztof Kozlowski , Andy Gross , "Paul Walmsley" , Palmer Dabbelt , Albert Ou , Jonathan Corbet CC: Hao Zhang , Greg Kroah-Hartman , , , , , Tingwei Zhang , Jinlong Mao , Yuanfang Zhang , Tao Zhang , Trilok Soni , , Bjorn Andersson , Subject: [PATCH v5 3/3] Documentation: trace: Add documentation for Coresight Dummy Trace Date: Fri, 26 May 2023 18:07:53 +0800 Message-ID: <20230526100753.34581-4-quic_hazha@quicinc.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20230526100753.34581-1-quic_hazha@quicinc.com> References: <20230526100753.34581-1-quic_hazha@quicinc.com> MIME-Version: 1.0 X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) To nasanex01a.na.qualcomm.com (10.52.223.231) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: BIKqSiad5Hb8lLy5TtcQ7omTW-4K6x1i X-Proofpoint-GUID: BIKqSiad5Hb8lLy5TtcQ7omTW-4K6x1i X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.957,Hydra:6.0.573,FMLib:17.11.176.26 definitions=2023-05-26_01,2023-05-25_03,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 spamscore=0 mlxlogscore=959 adultscore=0 priorityscore=1501 suspectscore=0 clxscore=1015 mlxscore=0 bulkscore=0 malwarescore=0 phishscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2304280000 definitions=main-2305260088 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add documentation for Coresight Dummy Trace under trace/coresight. Signed-off-by: Hao Zhang Reviewed-by: Bagas Sanjaya --- .../trace/coresight/coresight-dummy.rst | 32 +++++++++++++++++++ 1 file changed, 32 insertions(+) create mode 100644 Documentation/trace/coresight/coresight-dummy.rst diff --git a/Documentation/trace/coresight/coresight-dummy.rst b/Documentat= ion/trace/coresight/coresight-dummy.rst new file mode 100644 index 000000000000..f0a92669288b --- /dev/null +++ b/Documentation/trace/coresight/coresight-dummy.rst @@ -0,0 +1,32 @@ +.. SPDX-License-Identifier: GPL-2.0 + +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D +Coresight Dummy Trace Module +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D + + :Author: Hao Zhang + :Date: May 2023 + +Introduction +------------ + +The Coresight dummy trace module is for the specific devices that kernel d= on't +have permission to access or configure, e.g., CoreSight TPDMs on Qualcomm +platforms. For these devices, a dummy driver is needed to register them as +Coresight devices. The module may also be used to define components that m= ay +not have any programming interfaces (e.g, static links), so that paths can= be +created in the driver. It provides Coresight API for operations on dummy +devices, such as enabling and disabling them. It also provides the Coresig= ht +dummy sink/source paths for debugging. + +Config details +-------------- + +There are two types of nodes, dummy sink and dummy source. These nodes +are available at ``/sys/bus/coresight/devices``. + +Example output:: + + $ ls -l /sys/bus/coresight/devices | grep dummy + dummy_sink0 -> ../../../devices/platform/soc@0/soc@0:sink/dummy_sink0 + dummy_source0 -> ../../../devices/platform/soc@0/soc@0:source/dummy_so= urce0 --=20 2.17.1