From: Suzuki K Poulose <suzuki.poulose@arm.com>
To: Jie Gan <jie.gan@oss.qualcomm.com>,
Mike Leach <mike.leach@linaro.org>,
James Clark <james.clark@linaro.org>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
Rob Herring <robh@kernel.org>,
Krzysztof Kozlowski <krzk+dt@kernel.org>,
Conor Dooley <conor+dt@kernel.org>,
Tingwei Zhang <tingwei.zhang@oss.qualcomm.com>,
Mao Jinlong <jinlong.mao@oss.qualcomm.com>,
Bjorn Andersson <andersson@kernel.org>,
Konrad Dybcio <konradybcio@kernel.org>
Cc: coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org,
devicetree@vger.kernel.org
Subject: Re: [PATCH v10 3/8] coresight: tmc: Introduce sysfs_read_ops to wrap sysfs read operations
Date: Thu, 22 Jan 2026 10:07:59 +0000 [thread overview]
Message-ID: <f78f72ec-9b57-4373-a7f0-a9295326832b@arm.com> (raw)
In-Reply-To: <20260122-enable-byte-cntr-for-ctcu-v10-3-22978e3c169f@oss.qualcomm.com>
On 22/01/2026 02:08, Jie Gan wrote:
> Introduce sysfs_read_ops as a wrapper, wrap sysfs read operations, for reading
> trace data from the TMC buffer.
>
> Reviewed-by: Mike Leach <mike.leach@linaro.org>
> Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
> ---
> drivers/hwtracing/coresight/coresight-tmc-core.c | 50 +++++++++++-------------
> drivers/hwtracing/coresight/coresight-tmc.h | 17 ++++++++
> 2 files changed, 40 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-tmc-core.c b/drivers/hwtracing/coresight/coresight-tmc-core.c
> index 1ea255ffa67c..8b0397a77e57 100644
> --- a/drivers/hwtracing/coresight/coresight-tmc-core.c
> +++ b/drivers/hwtracing/coresight/coresight-tmc-core.c
> @@ -232,17 +232,10 @@ static int tmc_read_prepare(struct tmc_drvdata *drvdata)
> {
> int ret = 0;
>
> - switch (drvdata->config_type) {
> - case TMC_CONFIG_TYPE_ETB:
> - case TMC_CONFIG_TYPE_ETF:
> - ret = tmc_read_prepare_etb(drvdata);
> - break;
> - case TMC_CONFIG_TYPE_ETR:
> - ret = tmc_read_prepare_etr(drvdata);
> - break;
> - default:
> + if (drvdata->sysfs_ops)
> + ret = drvdata->sysfs_ops->read_prepare(drvdata);
> + else
> ret = -EINVAL;
> - }
>
> if (!ret)
> dev_dbg(&drvdata->csdev->dev, "TMC read start\n");
> @@ -254,17 +247,10 @@ static int tmc_read_unprepare(struct tmc_drvdata *drvdata)
> {
> int ret = 0;
>
> - switch (drvdata->config_type) {
> - case TMC_CONFIG_TYPE_ETB:
> - case TMC_CONFIG_TYPE_ETF:
> - ret = tmc_read_unprepare_etb(drvdata);
> - break;
> - case TMC_CONFIG_TYPE_ETR:
> - ret = tmc_read_unprepare_etr(drvdata);
> - break;
> - default:
> + if (drvdata->sysfs_ops)
> + ret = drvdata->sysfs_ops->read_unprepare(drvdata);
> + else
> ret = -EINVAL;
> - }
>
> if (!ret)
> dev_dbg(&drvdata->csdev->dev, "TMC read end\n");
> @@ -291,13 +277,8 @@ static int tmc_open(struct inode *inode, struct file *file)
> static ssize_t tmc_get_sysfs_trace(struct tmc_drvdata *drvdata, loff_t pos, size_t len,
> char **bufpp)
> {
> - switch (drvdata->config_type) {
> - case TMC_CONFIG_TYPE_ETB:
> - case TMC_CONFIG_TYPE_ETF:
> - return tmc_etb_get_sysfs_trace(drvdata, pos, len, bufpp);
> - case TMC_CONFIG_TYPE_ETR:
> - return tmc_etr_get_sysfs_trace(drvdata, pos, len, bufpp);
> - }
> + if (drvdata->sysfs_ops)
> + return drvdata->sysfs_ops->get_trace_data(drvdata, pos, len, bufpp);
minor nit: Please could we bail out in tmc_open() if the
drvdata->sysfs_ops is not set. That way, we don't have to sprinkle it
everywhere. And also, we don't expect to see this case anyways.
>
> return -EINVAL;
> }
> @@ -769,6 +750,18 @@ static void register_crash_dev_interface(struct tmc_drvdata *drvdata,
> "Valid crash tracedata found\n");
> }
>
> +static const struct sysfs_read_ops tmc_etb_sysfs_read_ops = {
minor nit: please could we rename the struct type to :
struct tmc_sysfs_ops
and then use
etb_sysfs_ops = {}
etr_sysfs_ops = {}
Rest looks fine to me
Suzuki
> + .read_prepare = tmc_read_prepare_etb,
> + .read_unprepare = tmc_read_unprepare_etb,
> + .get_trace_data = tmc_etb_get_sysfs_trace,
> +};
> +
> +static const struct sysfs_read_ops tmc_etr_sysfs_read_ops = {
> + .read_prepare = tmc_read_prepare_etr,
> + .read_unprepare = tmc_read_unprepare_etr,
> + .get_trace_data = tmc_etr_get_sysfs_trace,
> +};
> +
> static int __tmc_probe(struct device *dev, struct resource *res)
> {
> int ret = 0;
> @@ -828,6 +821,7 @@ static int __tmc_probe(struct device *dev, struct resource *res)
> desc.subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_BUFFER;
> desc.ops = &tmc_etb_cs_ops;
> dev_list = &etb_devs;
> + drvdata->sysfs_ops = &tmc_etb_sysfs_read_ops;
> break;
> case TMC_CONFIG_TYPE_ETR:
> desc.groups = coresight_etr_groups;
> @@ -841,6 +835,7 @@ static int __tmc_probe(struct device *dev, struct resource *res)
> mutex_init(&drvdata->idr_mutex);
> dev_list = &etr_devs;
> INIT_LIST_HEAD(&drvdata->etr_buf_list);
> + drvdata->sysfs_ops = &tmc_etr_sysfs_read_ops;
> break;
> case TMC_CONFIG_TYPE_ETF:
> desc.groups = coresight_etf_groups;
> @@ -849,6 +844,7 @@ static int __tmc_probe(struct device *dev, struct resource *res)
> desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_FIFO;
> desc.ops = &tmc_etf_cs_ops;
> dev_list = &etf_devs;
> + drvdata->sysfs_ops = &tmc_etb_sysfs_read_ops;
> break;
> default:
> pr_err("%s: Unsupported TMC config\n", desc.name);
> diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
> index 9b3c4e6f0a5e..c9a82ff6cd00 100644
> --- a/drivers/hwtracing/coresight/coresight-tmc.h
> +++ b/drivers/hwtracing/coresight/coresight-tmc.h
> @@ -221,6 +221,8 @@ struct etr_buf_node {
> struct list_head node;
> };
>
> +struct sysfs_read_ops;
> +
> /**
> * struct tmc_drvdata - specifics associated to an TMC component
> * @atclk: optional clock for the core parts of the TMC.
> @@ -258,6 +260,7 @@ struct etr_buf_node {
> * Used by ETR/ETF.
> * @etr_buf_list: List that is used to manage allocated etr_buf.
> * @reading_node: Available buffer_node for byte-cntr reading.
> + * @sysfs_ops: Read operations for sysfs mode.
> */
> struct tmc_drvdata {
> struct clk *atclk;
> @@ -290,6 +293,20 @@ struct tmc_drvdata {
> struct tmc_resrv_buf crash_mdata;
> struct list_head etr_buf_list;
> struct etr_buf_node *reading_node;
> + const struct sysfs_read_ops *sysfs_ops;
> +};
> +
> +/**
> + * struct sysfs_read_ops - read operations for TMC and its helper devices
> + * @read_prepare: prepare operation.
> + * @read_unprepare: unprepare operation.
> + * @get_trace_data: read operation.
> + */
> +struct sysfs_read_ops {
> + int (*read_prepare)(struct tmc_drvdata *drvdata);
> + int (*read_unprepare)(struct tmc_drvdata *drvdata);
> + ssize_t (*get_trace_data)(struct tmc_drvdata *drvdata, loff_t pos,
> + size_t len, char **bufpp);
> };
>
> struct etr_buf_operations {
>
next prev parent reply other threads:[~2026-01-22 10:08 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-22 2:08 [PATCH v10 0/8] coresight: ctcu: Enable byte-cntr function for TMC ETR Jie Gan
2026-01-22 2:08 ` [PATCH v10 1/8] coresight: core: Refactoring ctcu_get_active_port and make it generic Jie Gan
2026-01-22 10:00 ` Suzuki K Poulose
2026-01-23 1:27 ` Jie Gan
2026-01-22 2:08 ` [PATCH v10 2/8] coresight: tmc: add create/clean functions for etr_buf_list Jie Gan
2026-01-22 2:08 ` [PATCH v10 3/8] coresight: tmc: Introduce sysfs_read_ops to wrap sysfs read operations Jie Gan
2026-01-22 10:07 ` Suzuki K Poulose [this message]
2026-01-23 1:32 ` Jie Gan
2026-01-22 2:08 ` [PATCH v10 4/8] coresight: etr: refactor the tmc_etr_get_catu_device function Jie Gan
2026-01-26 16:10 ` Suzuki K Poulose
2026-01-27 1:00 ` Jie Gan
2026-01-22 2:08 ` [PATCH v10 5/8] dt-bindings: arm: add an interrupt property for Coresight CTCU Jie Gan
2026-01-26 17:22 ` Suzuki K Poulose
2026-01-27 0:59 ` Jie Gan
2026-01-22 2:08 ` [PATCH v10 6/8] coresight: ctcu: enable byte-cntr for TMC ETR devices Jie Gan
2026-01-22 2:08 ` [PATCH v10 7/8] coresight: tmc: integrate byte-cntr's read_ops with sysfs file_ops Jie Gan
2026-01-22 2:08 ` [PATCH v10 8/8] arm64: dts: qcom: lemans: add interrupts to CTCU device Jie Gan
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=f78f72ec-9b57-4373-a7f0-a9295326832b@arm.com \
--to=suzuki.poulose@arm.com \
--cc=alexander.shishkin@linux.intel.com \
--cc=andersson@kernel.org \
--cc=conor+dt@kernel.org \
--cc=coresight@lists.linaro.org \
--cc=devicetree@vger.kernel.org \
--cc=james.clark@linaro.org \
--cc=jie.gan@oss.qualcomm.com \
--cc=jinlong.mao@oss.qualcomm.com \
--cc=konradybcio@kernel.org \
--cc=krzk+dt@kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mike.leach@linaro.org \
--cc=robh@kernel.org \
--cc=tingwei.zhang@oss.qualcomm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®