From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id C507177A1E; Mon, 3 Jun 2024 10:08:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717409284; cv=none; b=UMAhA1Pb020xISq8ecoZQF1WoYXsc6jjjYRPlCC/PxavAcoMcQ5ItcGIaz+JFuo/4WHPN6Ys1bBBmKc8v+YI7BxR6qlWSPtuKl89nN/8QF0sPVGaVv0YKk3qjOHzMG7UmLJu/pFe79k15bGn9m9cCrHxbcO1cblMGT6PBP7Diz4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717409284; c=relaxed/simple; bh=8qBYXdJrDRJA+p+7GoU2rvppnvWsbbP8MLHmqvz8jA8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=mPqpo8hE8oKRfayW5eYkxhBixzmaGRf0EMT+Gu+UryHG/rYalEhoMQMtsrHwSzEejGUjjxsGN01szUf4p06EQwMxhNx18vdvx3rYAGfbfznjWvWmszDtblyDtDpGPU879FYKln4P5Yf39gmioMRGYBwCExbVQvDjisuEc5mxPIA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com 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 5FB711042; Mon, 3 Jun 2024 03:08:26 -0700 (PDT) Received: from [192.168.1.100] (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1CCB23F792; Mon, 3 Jun 2024 03:08:00 -0700 (PDT) Message-ID: <1802b338-e2e5-4b9b-b914-869651fa886c@arm.com> Date: Mon, 3 Jun 2024 11:07:59 +0100 Precedence: bulk X-Mailing-List: linux-arm-msm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 3/3] coresight: dummy: Add reserve atid support for dummy source To: Mao Jinlong Cc: coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, Tingwei Zhang , Yuanfang Zhang , Tao Zhang , songchai , Suzuki K Poulose , Mike Leach , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Alexander Shishkin References: <20240603094354.2348-1-quic_jinlmao@quicinc.com> <20240603094354.2348-4-quic_jinlmao@quicinc.com> Content-Language: en-US From: James Clark In-Reply-To: <20240603094354.2348-4-quic_jinlmao@quicinc.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 03/06/2024 10:43, Mao Jinlong wrote: > Some dummy source has static trace id configured in HW and it cannot > be changed via software programming. Configure the trace id in device > tree and reserve the id when device probe. > > Signed-off-by: Mao Jinlong > --- > .../sysfs-bus-coresight-devices-dummy-source | 15 +++++ > drivers/hwtracing/coresight/coresight-dummy.c | 58 +++++++++++++++++-- > 2 files changed, 69 insertions(+), 4 deletions(-) > create mode 100644 Documentation/ABI/testing/sysfs-bus-coresight-devices-dummy-source > > diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-dummy-source b/Documentation/ABI/testing/sysfs-bus-coresight-devices-dummy-source > new file mode 100644 > index 000000000000..d93c198115c9 > --- /dev/null > +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-dummy-source > @@ -0,0 +1,15 @@ > +What: /sys/bus/coresight/devices/dummy_source/enable_source > +Date: June 2024 > +KernelVersion: 6.9 > +Contact: Mao Jinlong > +Description: (RW) Enable/disable tracing of dummy source. A sink should be activated > + before enabling the source. The path of coresight components linking > + the source to the sink is configured and managed automatically by the > + coresight framework. > + > +What: /sys/bus/coresight/devices/dummy_source/traceid > +Date: June 2024 > +KernelVersion: 6.9 > +Contact: Mao Jinlong > +Description: (R) Show the trace ID that will appear in the trace stream > + coming from this trace entity. > diff --git a/drivers/hwtracing/coresight/coresight-dummy.c b/drivers/hwtracing/coresight/coresight-dummy.c > index ac70c0b491be..1f7133ac2c0b 100644 > --- a/drivers/hwtracing/coresight/coresight-dummy.c > +++ b/drivers/hwtracing/coresight/coresight-dummy.c > @@ -11,10 +11,12 @@ > #include > > #include "coresight-priv.h" > +#include "coresight-trace-id.h" > > struct dummy_drvdata { > struct device *dev; > struct coresight_device *csdev; > + u8 traceid; > }; > > DEFINE_CORESIGHT_DEVLIST(source_devs, "dummy_source"); > @@ -67,6 +69,32 @@ static const struct coresight_ops dummy_sink_cs_ops = { > .sink_ops = &dummy_sink_ops, > }; > > +/* User can get the trace id of dummy source from this node. */ > +static ssize_t traceid_show(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + unsigned long val; > + struct dummy_drvdata *drvdata = dev_get_drvdata(dev->parent); > + > + val = drvdata->traceid; > + return scnprintf(buf, PAGE_SIZE, "%#lx\n", val); > +} > +static DEVICE_ATTR_RO(traceid); > + > +static struct attribute *coresight_dummy_attrs[] = { > + &dev_attr_traceid.attr, > + NULL, > +}; > + > +static const struct attribute_group coresight_dummy_group = { > + .attrs = coresight_dummy_attrs, > +}; > + > +static const struct attribute_group *coresight_dummy_groups[] = { > + &coresight_dummy_group, > + NULL, > +}; > + > static int dummy_probe(struct platform_device *pdev) > { > struct device *dev = &pdev->dev; > @@ -74,6 +102,11 @@ static int dummy_probe(struct platform_device *pdev) > struct coresight_platform_data *pdata; > struct dummy_drvdata *drvdata; > struct coresight_desc desc = { 0 }; > + int ret, trace_id; > + > + drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL); > + if (!drvdata) > + return -ENOMEM; > > if (of_device_is_compatible(node, "arm,coresight-dummy-source")) { > > @@ -85,6 +118,24 @@ static int dummy_probe(struct platform_device *pdev) > desc.subtype.source_subtype = > CORESIGHT_DEV_SUBTYPE_SOURCE_OTHERS; > desc.ops = &dummy_source_cs_ops; > + desc.groups = coresight_dummy_groups; > + > + ret = coresight_get_source_traceid(dev, &trace_id); > + if (!ret) { > + ret = coresight_trace_id_get_system_id(trace_id); > + if (ret < 0) > + return ret; > + > + drvdata->traceid = ret; > + } else { > + trace_id = coresight_trace_id_get_system_id(0); > + if (trace_id < 0) { > + ret = trace_id; > + return ret; > + } > + drvdata->traceid = (u8)trace_id; > + } > + It's a bit weird to use ret in one version and trace_id in the other. And one casts to (u8) but the other doesn't. I'm sure it all compiles to the same in the end but it would be a bit more readable if it was more consistent. > } else if (of_device_is_compatible(node, "arm,coresight-dummy-sink")) { > desc.name = coresight_alloc_device_name(&sink_devs, dev); > if (!desc.name) > @@ -103,10 +154,6 @@ static int dummy_probe(struct platform_device *pdev) > 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); > > @@ -126,7 +173,10 @@ static void dummy_remove(struct platform_device *pdev) > { > struct dummy_drvdata *drvdata = platform_get_drvdata(pdev); > struct device *dev = &pdev->dev; > + struct device_node *node = dev->of_node; > > + if (of_device_is_compatible(node, "arm,coresight-dummy-source")) > + coresight_trace_id_put_system_id(drvdata->traceid); > pm_runtime_disable(dev); > coresight_unregister(drvdata->csdev); > }