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[v5,0/5] coresight: Add remote etm support

Message ID 20250424115854.2328190-1-quic_jinlmao@quicinc.com
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Series coresight: Add remote etm support | expand

Message

Mao Jinlong April 24, 2025, 11:58 a.m. UTC 
The system on chip (SoC) consists of main APSS(Applications processor
subsytem) and additional processors like modem, lpass. There is
coresight-etm driver for etm trace of APSS. Coresight remote etm driver
is for enabling and disabling the etm trace of remote processors.
It uses QMI interface to communicate with remote processors' software
and uses coresight framework to configure the connection from remote
etm source to TMC sinks.

Example to capture the remote etm trace:

Enable source:
echo 1 > /sys/bus/coresight/devices/tmc_etf0/enable_sink
echo 1 > /sys/bus/coresight/devices/remote_etm0/enable_source

Capture the trace:
cat /dev/tmc_etf0 > /data/remote_etm.bin

Disable source:
echo 0 > /sys/bus/coresight/devices/remote_etm0/enable_source

Changes since V4:
1. Add coresight QMI driver
2. Add coresight qmi node and qcom,qmi-id of modem-etm in msm8996 dtsi

Changes since V3:
1. Use different compatible for different remote etms in dt.
2. Get qmi instance id from the match table data in driver.

Change since V2:
1. Change qcom,inst-id to qcom,qmi-id
2. Fix the error in code for type of remote_etm_remove
3. Depend on QMI helper in Kconfig

Changes since V1:
1. Remove unused content
2. Use CORESIGHT_DEV_SUBTYPE_SOURCE_OTHERS as remote etm source type.
3. Use enabled instead of enable in driver data.
4. Validate instance id value where it's read from the DT.

Mao Jinlong (5):
  dt-bindings: arm: Add CoreSight QMI component description
  coresight: Add coresight QMI driver
  dt-bindings: arm: Add qcom,qmi-id for remote etm
  coresight: Add remote etm support
  arm64: dts: qcom: msm8996: Add coresight qmi node

 .../bindings/arm/qcom,coresight-qmi.yaml      |  65 +++++
 .../arm/qcom,coresight-remote-etm.yaml        |  10 +
 arch/arm64/boot/dts/qcom/msm8996.dtsi         |  11 +
 drivers/hwtracing/coresight/Kconfig           |  24 ++
 drivers/hwtracing/coresight/Makefile          |   2 +
 drivers/hwtracing/coresight/coresight-qmi.c   | 209 +++++++++++++++
 drivers/hwtracing/coresight/coresight-qmi.h   | 107 ++++++++
 .../coresight/coresight-remote-etm.c          | 252 ++++++++++++++++++
 8 files changed, 680 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/arm/qcom,coresight-qmi.yaml
 create mode 100644 drivers/hwtracing/coresight/coresight-qmi.c
 create mode 100644 drivers/hwtracing/coresight/coresight-qmi.h
 create mode 100644 drivers/hwtracing/coresight/coresight-remote-etm.c

Comments

Konrad Dybcio April 25, 2025, 7:58 p.m. UTC | #1 
On 4/24/25 1:58 PM, Mao Jinlong wrote:
> Coresight QMI driver uses QMI(Qualcomm Messaging Interface) interfaces
> to communicate with remote subsystems. Driver gets the instance id and
> service id from device tree node and init the QMI connections to remote
> subsystems. Send request function is for other coresight drivers to
> communicate with remote subsystems.
> 
> Signed-off-by: Mao Jinlong <quic_jinlmao@quicinc.com>
> ---

[...]

> +static int coresight_qmi_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct device_node *node = pdev->dev.of_node;
> +	struct device_node *child_node;
> +	int ret;
> +
> +	/**

Two starts means kerneldoc, please use one for a normal multiline comment

> +	 * Get the instance id and service id of the QMI service connection
> +	 * from DT node. Creates QMI handle and register new lookup for each

The first sentence is a bit redundant.

In the second, Creates -> Create for imperative mood

[...]

> +static const struct of_device_id coresight_qmi_match[] = {
> +	{.compatible = "qcom,coresight-qmi"},

Nit: please add a space after { and before }

> +	{}
> +};
> +
> +static struct platform_driver coresight_qmi_driver = {
> +	.probe          = coresight_qmi_probe,
> +	.remove         = coresight_qmi_remove,
> +	.driver         = {
> +		.name   = "coresight-qmi",
> +		.of_match_table = coresight_qmi_match,
> +	},
> +};
> +
> +static int __init coresight_qmi_init(void)
> +{
> +	return platform_driver_register(&coresight_qmi_driver);
> +}
> +module_init(coresight_qmi_init);
> +
> +static void __exit coresight_qmi_exit(void)
> +{
> +	platform_driver_unregister(&coresight_qmi_driver);
> +}
> +module_exit(coresight_qmi_exit);

You can drop the __init and __exit funcs and substitute them
with module_platform_driver()

> +
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("CoreSight QMI driver");
> diff --git a/drivers/hwtracing/coresight/coresight-qmi.h b/drivers/hwtracing/coresight/coresight-qmi.h
> new file mode 100644
> index 000000000000..1d57e46177b8
> --- /dev/null
> +++ b/drivers/hwtracing/coresight/coresight-qmi.h
> @@ -0,0 +1,107 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (c) 2025 Qualcomm Innovation Center, Inc. All rights reserved.
> + */
> +#ifndef _CORESIGHT_QMI_H
> +#define _CORESIGHT_QMI_H
> +
> +#include <linux/soc/qcom/qmi.h>
> +
> +#define CORESIGHT_QMI_VERSION			(1)
> +
> +#define CORESIGHT_QMI_SET_ETM_REQ_V01		(0x002C)
> +#define CORESIGHT_QMI_SET_ETM_RESP_V01		(0x002C)
> +
> +#define CORESIGHT_QMI_MAX_MSG_LEN (50)
> +
> +#define TIMEOUT_MS				(10000)

Parentheses around constants are unnecesary

> +
> +/* Qmi data for the QMI connection */
> +struct qmi_data {
> +	u32			qmi_id;
> +	u32			service_id;
> +	struct list_head	node;
> +	struct qmi_handle	handle;
> +	bool			service_connected;
> +	struct sockaddr_qrtr	s_addr;
> +};
> +
> +/**
> + * QMI service IDs

This is not valid kerneldoc, try make W=1

Konrad