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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0763FC6FD20 for ; Fri, 24 Mar 2023 10:44:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231289AbjCXKog (ORCPT ); Fri, 24 Mar 2023 06:44:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37488 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230088AbjCXKof (ORCPT ); Fri, 24 Mar 2023 06:44:35 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 6532EF977; Fri, 24 Mar 2023 03:44:33 -0700 (PDT) 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 2A8BE11FB; Fri, 24 Mar 2023 03:45:17 -0700 (PDT) Received: from [10.57.55.150] (unknown [10.57.55.150]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B0B6B3F6C4; Fri, 24 Mar 2023 03:44:27 -0700 (PDT) Message-ID: <0c1d60f7-0d01-832f-a49c-12527665e86e@arm.com> Date: Fri, 24 Mar 2023 10:44:26 +0000 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.9.0 Subject: Re: [PATCH v2 1/3] Coresight: Add coresight dummy driver To: Hao Zhang , Mathieu Poirier , Alexander Shishkin , Konrad Dybcio , Mike Leach , Rob Herring , Krzysztof Kozlowski , Andy Gross , Paul Walmsley , Palmer Dabbelt , Albert Ou , Jonathan Corbet Cc: Leo Yan , Greg Kroah-Hartman , coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Tingwei Zhang , Jinlong Mao , Yuanfang Zhang , Tao Zhang , Trilok Soni , linux-arm-msm@vger.kernel.org, Bjorn Andersson , linux-doc@vger.kernel.org References: <20230324061608.33609-1-quic_hazha@quicinc.com> <20230324061608.33609-2-quic_hazha@quicinc.com> From: Suzuki K Poulose In-Reply-To: <20230324061608.33609-2-quic_hazha@quicinc.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On 24/03/2023 06:16, Hao Zhang wrote: > Some Coresight devices that HLOS don't have permission to access > or configure. Such as Coresight sink EUD, some TPDMs etc. So there > need driver to register dummy devices as Coresight devices. Provide > Coresight API for dummy device operations, such as enabling and > disabling dummy devices. Build the Coresight path for dummy sink or > dummy source for debugging. > > Signed-off-by: Hao Zhang > --- > drivers/hwtracing/coresight/Kconfig | 11 ++ > drivers/hwtracing/coresight/Makefile | 1 + > drivers/hwtracing/coresight/coresight-dummy.c | 176 ++++++++++++++++++ > 3 files changed, 188 insertions(+) > create mode 100644 drivers/hwtracing/coresight/coresight-dummy.c > > diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig > index 2b5bbfffbc4f..06f0a7594169 100644 > --- a/drivers/hwtracing/coresight/Kconfig > +++ b/drivers/hwtracing/coresight/Kconfig > @@ -236,4 +236,15 @@ config CORESIGHT_TPDA > > To compile this driver as a module, choose M here: the module will be > called coresight-tpda. > + > +config CORESIGHT_DUMMY > + tristate "Dummy driver support" > + help > + Enables support for dummy driver. Dummy driver can be used for > + CoreSight sources/sinks that are owned and configured by some > + other subsystem and use Linux drivers to configure rest of trace > + path. > + > + To compile this driver as a module, choose M here: the module will be > + called coresight-dummy. > endif > diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile > index 33bcc3f7b8ae..995d3b2c76df 100644 > --- a/drivers/hwtracing/coresight/Makefile > +++ b/drivers/hwtracing/coresight/Makefile > @@ -30,3 +30,4 @@ obj-$(CONFIG_CORESIGHT_TPDA) += coresight-tpda.o > coresight-cti-y := coresight-cti-core.o coresight-cti-platform.o \ > coresight-cti-sysfs.o > obj-$(CONFIG_ULTRASOC_SMB) += ultrasoc-smb.o > +obj-$(CONFIG_CORESIGHT_DUMMY) += coresight-dummy.o > diff --git a/drivers/hwtracing/coresight/coresight-dummy.c b/drivers/hwtracing/coresight/coresight-dummy.c > new file mode 100644 > index 000000000000..2d4eb3e546eb > --- /dev/null > +++ b/drivers/hwtracing/coresight/coresight-dummy.c > @@ -0,0 +1,176 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include "coresight-priv.h" > +#include "coresight-trace-id.h" > + > +struct dummy_drvdata { > + struct device *dev; > + struct coresight_device *csdev; > + int traceid; > +}; > + > +DEFINE_CORESIGHT_DEVLIST(dummy_devs, "dummy"); > + > +static int dummy_source_enable(struct coresight_device *csdev, > + struct perf_event *event, u32 mode) > +{ > + struct dummy_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); > + > + dev_info(drvdata->dev, "Dummy source enabled\n"); Please use dev_dbg everywher. > + > + return 0; > +} > + > +static void dummy_source_disable(struct coresight_device *csdev, > + struct perf_event *event) > +{ > + struct dummy_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); > + > + dev_info(drvdata->dev, "Dummy source disabled\n"); > +} > + > +static int dummy_sink_enable(struct coresight_device *csdev, u32 mode, > + void *data) > +{ > + struct dummy_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); > + > + dev_info(drvdata->dev, "Dummy sink enabled\n"); > + > + return 0; > +} > + > +static int dummy_sink_disable(struct coresight_device *csdev) > +{ > + struct dummy_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); > + > + dev_info(drvdata->dev, "Dummy sink disabled\n"); > + > + return 0; > +} > + > +static const struct coresight_ops_source dummy_source_ops = { > + .enable = dummy_source_enable, > + .disable = dummy_source_disable, > +}; > + > +static const struct coresight_ops_sink dummy_sink_ops = { > + .enable = dummy_sink_enable, > + .disable = dummy_sink_disable, > +}; > + > +static const struct coresight_ops dummy_cs_ops = { > + .source_ops = &dummy_source_ops, > + .sink_ops = &dummy_sink_ops, > +}; > + > +static int dummy_probe(struct platform_device *pdev) > +{ > + int ret, trace_id; > + struct device *dev = &pdev->dev; > + struct coresight_platform_data *pdata; > + struct dummy_drvdata *drvdata; > + struct coresight_desc desc = { 0 }; > + > + desc.name = coresight_alloc_device_name(&dummy_devs, dev); > + if (!desc.name) > + return -ENOMEM; > + > + pdata = coresight_get_platform_data(dev); > + if (IS_ERR(pdata)) > + return PTR_ERR(pdata); > + pdev->dev.platform_data = pdata; > + > + drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL); > + if (!drvdata) > + return -ENOMEM; > + > + drvdata->dev = &pdev->dev; > + platform_set_drvdata(pdev, drvdata); > + > + if (of_property_read_bool(pdev->dev.of_node, "qcom,dummy-source")) { I don't see any reason why this should be qcom,... Please could we use : "arm,coresight-", everywhere including the "dt" compatible ? > + desc.type = CORESIGHT_DEV_TYPE_SOURCE; > + desc.subtype.source_subtype = > + CORESIGHT_DEV_SUBTYPE_SOURCE_OTHERS; > + } else if (of_property_read_bool(pdev->dev.of_node, > + "qcom,dummy-sink")) { > + desc.type = CORESIGHT_DEV_TYPE_SINK; > + desc.subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_BUFFER; > + } else { > + dev_info(dev, "Device type not set\n"); > + return -EINVAL; > + } > + > + desc.ops = &dummy_cs_ops; > + desc.pdata = pdev->dev.platform_data; > + desc.dev = &pdev->dev; > + drvdata->csdev = coresight_register(&desc); > + if (IS_ERR(drvdata->csdev)) > + return PTR_ERR(drvdata->csdev); > + > + trace_id = coresight_trace_id_get_system_id(); > + if (trace_id < 0) { > + ret = trace_id; > + goto cs_unregister; > + } > + drvdata->traceid = (u8)trace_id; > + > + pm_runtime_enable(dev); > + dev_info(dev, "Dummy device initialized\n"); > + > + return 0; > + > +cs_unregister: > + coresight_unregister(drvdata->csdev); > + > + return ret; > +} > + > +static int dummy_remove(struct platform_device *pdev) > +{ > + struct dummy_drvdata *drvdata = platform_get_drvdata(pdev); > + struct device *dev = &pdev->dev; > + > + coresight_trace_id_put_system_id(drvdata->traceid); > + pm_runtime_disable(dev); > + coresight_unregister(drvdata->csdev); > + return 0; > +} > + > +static const struct of_device_id dummy_match[] = { > + {.compatible = "qcom,coresight-dummy"}, As mentioned above, "arm,coresight-dummy-device" ? This has nothing to do with qcom IP. qcom has a use for this. So, I would like to keep this "coresight" subsystem specific compatibles. May be we could even add other types too : i.e, arm,coresight-dummy-link-split, arm,coresight-dummy-link-merge Suzuki > + {}, > +}; > + > +static struct platform_driver dummy_driver = { > + .probe = dummy_probe, > + .remove = dummy_remove, > + .driver = { > + .name = "coresight-dummy", > + .of_match_table = dummy_match, > + }, > +}; > + > +static int __init dummy_init(void) > +{ > + return platform_driver_register(&dummy_driver); > +} > +module_init(dummy_init); > + > +static void __exit dummy_exit(void) > +{ > + platform_driver_unregister(&dummy_driver); > +} > +module_exit(dummy_exit); > + > +MODULE_LICENSE("GPL"); > +MODULE_DESCRIPTION("CoreSight dummy source driver");