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[PATCH v6 4/4] coresight: tpda: add sysfs node to flush specific port

Jie Gan posted 4 patches 1 month, 2 weeks ago
[PATCH v6 4/4] coresight: tpda: add sysfs node to flush specific port
Posted by Jie Gan 1 month, 2 weeks ago 
From: Tao Zhang <tao.zhang@oss.qualcomm.com>

Setting bit i in the TPDA_FLUSH_CR register initiates a flush request
for port i, forcing the data to synchronize and be transmitted to the
sink device.

Signed-off-by: Tao Zhang <tao.zhang@oss.qualcomm.com>
Reviewed-by: James Clark <james.clark@linaro.org>
Co-developed-by: Jie Gan <jie.gan@oss.qualcomm.com>
Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
---
 .../ABI/testing/sysfs-bus-coresight-devices-tpda   |  7 ++++
 drivers/hwtracing/coresight/coresight-tpda.c       | 40 ++++++++++++++++++++++
 drivers/hwtracing/coresight/coresight-tpda.h       |  1 +
 3 files changed, 48 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda
index d359d90dca72..df8f03d4b573 100644
--- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda
+++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda
@@ -51,3 +51,10 @@ Description:
 		mode 0 - COUNT[11:0] value represents the approximate number of bytes moved between two ASYNC packet requests
 		mode 1 - the bits COUNT[11:7] are used as a power of 2. for example, we could insert an async packet every 8K
 		         data by writing a value 13 to the COUNT[11:7] field.
+
+What:		/sys/bus/coresight/devices/<tpda-name>/port_flush_req
+Date:		December 2025
+KernelVersion:	6.19
+Contact:	Jinlong Mao <jinlong.mao@oss.qualcomm.com>, Tao Zhang <tao.zhang@oss.qualcomm.com>, Jie Gan <jie.gan@oss.qualcomm.com>
+Description:
+		(RW) Configure the bit i to requests a flush operation of port i on the TPDA.
diff --git a/drivers/hwtracing/coresight/coresight-tpda.c b/drivers/hwtracing/coresight/coresight-tpda.c
index 7baa8a0965d3..f79fea4fbb2c 100644
--- a/drivers/hwtracing/coresight/coresight-tpda.c
+++ b/drivers/hwtracing/coresight/coresight-tpda.c
@@ -430,9 +430,49 @@ static ssize_t syncr_mode_store(struct device *dev,
 }
 static DEVICE_ATTR_RW(syncr_mode);
 
+static ssize_t port_flush_req_show(struct device *dev,
+				   struct device_attribute *attr,
+				   char *buf)
+{
+	struct tpda_drvdata *drvdata = dev_get_drvdata(dev->parent);
+	unsigned long val;
+
+	if (!drvdata->csdev->refcnt)
+		return -EINVAL;
+
+	guard(spinlock)(&drvdata->spinlock);
+	val = readl_relaxed(drvdata->base + TPDA_FLUSH_CR);
+
+	return sysfs_emit(buf, "0x%lx\n", val);
+}
+
+static ssize_t port_flush_req_store(struct device *dev,
+				    struct device_attribute *attr,
+				    const char *buf,
+				    size_t size)
+{
+	struct tpda_drvdata *drvdata = dev_get_drvdata(dev->parent);
+	u32 val;
+
+	if (kstrtou32(buf, 0, &val))
+		return -EINVAL;
+
+	if (!drvdata->csdev->refcnt || !val)
+		return -EINVAL;
+
+	guard(spinlock)(&drvdata->spinlock);
+	CS_UNLOCK(drvdata->base);
+	writel_relaxed(val, drvdata->base + TPDA_FLUSH_CR);
+	CS_LOCK(drvdata->base);
+
+	return size;
+}
+static DEVICE_ATTR_RW(port_flush_req);
+
 static struct attribute *tpda_attrs[] = {
 	&dev_attr_global_flush_req.attr,
 	&dev_attr_syncr_mode.attr,
+	&dev_attr_port_flush_req.attr,
 	tpda_trig_sysfs_rw(freq_ts_enable, FREQTS),
 	tpda_trig_sysfs_rw(trig_freq_enable, FRIE),
 	tpda_trig_sysfs_rw(trig_flag_ts_enable, FLRIE),
diff --git a/drivers/hwtracing/coresight/coresight-tpda.h b/drivers/hwtracing/coresight/coresight-tpda.h
index 1d2de50bb9f9..ef1ce2ce36a9 100644
--- a/drivers/hwtracing/coresight/coresight-tpda.h
+++ b/drivers/hwtracing/coresight/coresight-tpda.h
@@ -10,6 +10,7 @@
 #define TPDA_Pn_CR(n)		(0x004 + (n * 4))
 #define TPDA_FPID_CR		(0x084)
 #define TPDA_SYNCR		(0x08C)
+#define TPDA_FLUSH_CR		(0x090)
 
 /* Cross trigger global (all ports) flush request bit */
 #define TPDA_CR_FLREQ		BIT(0)

-- 
2.34.1
Re: [PATCH v6 4/4] coresight: tpda: add sysfs node to flush specific port
Posted by Suzuki K Poulose 1 month, 2 weeks ago 
On 22/12/2025 06:02, Jie Gan wrote:
> From: Tao Zhang <tao.zhang@oss.qualcomm.com>
> 
> Setting bit i in the TPDA_FLUSH_CR register initiates a flush request
> for port i, forcing the data to synchronize and be transmitted to the
> sink device.
> 
> Signed-off-by: Tao Zhang <tao.zhang@oss.qualcomm.com>
> Reviewed-by: James Clark <james.clark@linaro.org>
> Co-developed-by: Jie Gan <jie.gan@oss.qualcomm.com>
> Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
> ---
>   .../ABI/testing/sysfs-bus-coresight-devices-tpda   |  7 ++++
>   drivers/hwtracing/coresight/coresight-tpda.c       | 40 ++++++++++++++++++++++
>   drivers/hwtracing/coresight/coresight-tpda.h       |  1 +
>   3 files changed, 48 insertions(+)
> 
> diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda
> index d359d90dca72..df8f03d4b573 100644
> --- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda
> +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda
> @@ -51,3 +51,10 @@ Description:
>   		mode 0 - COUNT[11:0] value represents the approximate number of bytes moved between two ASYNC packet requests
>   		mode 1 - the bits COUNT[11:7] are used as a power of 2. for example, we could insert an async packet every 8K
>   		         data by writing a value 13 to the COUNT[11:7] field.
> +
> +What:		/sys/bus/coresight/devices/<tpda-name>/port_flush_req
> +Date:		December 2025
> +KernelVersion:	6.19
> +Contact:	Jinlong Mao <jinlong.mao@oss.qualcomm.com>, Tao Zhang <tao.zhang@oss.qualcomm.com>, Jie Gan <jie.gan@oss.qualcomm.com>
> +Description:
> +		(RW) Configure the bit i to requests a flush operation of port i on the TPDA.

Does this have similar semantics as the "global_flush_req"  for "Read" ? 
i.e., the bit stays set until the request completes ? Otherwise, why 
isn't this Write only ?

I don't see the point of "Reading" this value back.

Suzuki

> diff --git a/drivers/hwtracing/coresight/coresight-tpda.c b/drivers/hwtracing/coresight/coresight-tpda.c
> index 7baa8a0965d3..f79fea4fbb2c 100644
> --- a/drivers/hwtracing/coresight/coresight-tpda.c
> +++ b/drivers/hwtracing/coresight/coresight-tpda.c
> @@ -430,9 +430,49 @@ static ssize_t syncr_mode_store(struct device *dev,
>   }
>   static DEVICE_ATTR_RW(syncr_mode);
>   
> +static ssize_t port_flush_req_show(struct device *dev,
> +				   struct device_attribute *attr,
> +				   char *buf)
> +{
> +	struct tpda_drvdata *drvdata = dev_get_drvdata(dev->parent);
> +	unsigned long val;
> +
> +	if (!drvdata->csdev->refcnt)
> +		return -EINVAL;
> +
> +	guard(spinlock)(&drvdata->spinlock);
> +	val = readl_relaxed(drvdata->base + TPDA_FLUSH_CR);
> +
> +	return sysfs_emit(buf, "0x%lx\n", val);
> +}
> +
> +static ssize_t port_flush_req_store(struct device *dev,
> +				    struct device_attribute *attr,
> +				    const char *buf,
> +				    size_t size)
> +{
> +	struct tpda_drvdata *drvdata = dev_get_drvdata(dev->parent);
> +	u32 val;
> +
> +	if (kstrtou32(buf, 0, &val))
> +		return -EINVAL;
> +
> +	if (!drvdata->csdev->refcnt || !val)
> +		return -EINVAL;
> +
> +	guard(spinlock)(&drvdata->spinlock);
> +	CS_UNLOCK(drvdata->base);
> +	writel_relaxed(val, drvdata->base + TPDA_FLUSH_CR);
> +	CS_LOCK(drvdata->base);
> +
> +	return size;
> +}
> +static DEVICE_ATTR_RW(port_flush_req);
> +
>   static struct attribute *tpda_attrs[] = {
>   	&dev_attr_global_flush_req.attr,
>   	&dev_attr_syncr_mode.attr,
> +	&dev_attr_port_flush_req.attr,
>   	tpda_trig_sysfs_rw(freq_ts_enable, FREQTS),
>   	tpda_trig_sysfs_rw(trig_freq_enable, FRIE),
>   	tpda_trig_sysfs_rw(trig_flag_ts_enable, FLRIE),
> diff --git a/drivers/hwtracing/coresight/coresight-tpda.h b/drivers/hwtracing/coresight/coresight-tpda.h
> index 1d2de50bb9f9..ef1ce2ce36a9 100644
> --- a/drivers/hwtracing/coresight/coresight-tpda.h
> +++ b/drivers/hwtracing/coresight/coresight-tpda.h
> @@ -10,6 +10,7 @@
>   #define TPDA_Pn_CR(n)		(0x004 + (n * 4))
>   #define TPDA_FPID_CR		(0x084)
>   #define TPDA_SYNCR		(0x08C)
> +#define TPDA_FLUSH_CR		(0x090)
>   
>   /* Cross trigger global (all ports) flush request bit */
>   #define TPDA_CR_FLREQ		BIT(0)
>
Re: [PATCH v6 4/4] coresight: tpda: add sysfs node to flush specific port
Posted by Jie Gan 1 month, 2 weeks ago 

On 12/22/2025 9:12 PM, Suzuki K Poulose wrote:
> On 22/12/2025 06:02, Jie Gan wrote:
>> From: Tao Zhang <tao.zhang@oss.qualcomm.com>
>>
>> Setting bit i in the TPDA_FLUSH_CR register initiates a flush request
>> for port i, forcing the data to synchronize and be transmitted to the
>> sink device.
>>
>> Signed-off-by: Tao Zhang <tao.zhang@oss.qualcomm.com>
>> Reviewed-by: James Clark <james.clark@linaro.org>
>> Co-developed-by: Jie Gan <jie.gan@oss.qualcomm.com>
>> Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
>> ---
>>   .../ABI/testing/sysfs-bus-coresight-devices-tpda   |  7 ++++
>>   drivers/hwtracing/coresight/coresight-tpda.c       | 40 ++++++++++++ 
>> ++++++++++
>>   drivers/hwtracing/coresight/coresight-tpda.h       |  1 +
>>   3 files changed, 48 insertions(+)
>>
>> diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices- 
>> tpda b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda
>> index d359d90dca72..df8f03d4b573 100644
>> --- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda
>> +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda
>> @@ -51,3 +51,10 @@ Description:
>>           mode 0 - COUNT[11:0] value represents the approximate number 
>> of bytes moved between two ASYNC packet requests
>>           mode 1 - the bits COUNT[11:7] are used as a power of 2. for 
>> example, we could insert an async packet every 8K
>>                    data by writing a value 13 to the COUNT[11:7] field.
>> +
>> +What:        /sys/bus/coresight/devices/<tpda-name>/port_flush_req
>> +Date:        December 2025
>> +KernelVersion:    6.19
>> +Contact:    Jinlong Mao <jinlong.mao@oss.qualcomm.com>, Tao Zhang 
>> <tao.zhang@oss.qualcomm.com>, Jie Gan <jie.gan@oss.qualcomm.com>
>> +Description:
>> +        (RW) Configure the bit i to requests a flush operation of 
>> port i on the TPDA.
> 
> Does this have similar semantics as the "global_flush_req"  for "Read" ? 

Yes, global_flush_req triggers all ports at once, whereas this node 
initiates a flush request for specific port(s).

For reading, we can check whether the flush request has completed.

Thanks,
Jie

> i.e., the bit stays set until the request completes ? Otherwise, why 
> isn't this Write only ?
> 
> I don't see the point of "Reading" this value back.
> 
> Suzuki
> 
>> diff --git a/drivers/hwtracing/coresight/coresight-tpda.c b/drivers/ 
>> hwtracing/coresight/coresight-tpda.c
>> index 7baa8a0965d3..f79fea4fbb2c 100644
>> --- a/drivers/hwtracing/coresight/coresight-tpda.c
>> +++ b/drivers/hwtracing/coresight/coresight-tpda.c
>> @@ -430,9 +430,49 @@ static ssize_t syncr_mode_store(struct device *dev,
>>   }
>>   static DEVICE_ATTR_RW(syncr_mode);
>> +static ssize_t port_flush_req_show(struct device *dev,
>> +                   struct device_attribute *attr,
>> +                   char *buf)
>> +{
>> +    struct tpda_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +    unsigned long val;
>> +
>> +    if (!drvdata->csdev->refcnt)
>> +        return -EINVAL;
>> +
>> +    guard(spinlock)(&drvdata->spinlock);
>> +    val = readl_relaxed(drvdata->base + TPDA_FLUSH_CR);
>> +
>> +    return sysfs_emit(buf, "0x%lx\n", val);
>> +}
>> +
>> +static ssize_t port_flush_req_store(struct device *dev,
>> +                    struct device_attribute *attr,
>> +                    const char *buf,
>> +                    size_t size)
>> +{
>> +    struct tpda_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +    u32 val;
>> +
>> +    if (kstrtou32(buf, 0, &val))
>> +        return -EINVAL;
>> +
>> +    if (!drvdata->csdev->refcnt || !val)
>> +        return -EINVAL;
>> +
>> +    guard(spinlock)(&drvdata->spinlock);
>> +    CS_UNLOCK(drvdata->base);
>> +    writel_relaxed(val, drvdata->base + TPDA_FLUSH_CR);
>> +    CS_LOCK(drvdata->base);
>> +
>> +    return size;
>> +}
>> +static DEVICE_ATTR_RW(port_flush_req);
>> +
>>   static struct attribute *tpda_attrs[] = {
>>       &dev_attr_global_flush_req.attr,
>>       &dev_attr_syncr_mode.attr,
>> +    &dev_attr_port_flush_req.attr,
>>       tpda_trig_sysfs_rw(freq_ts_enable, FREQTS),
>>       tpda_trig_sysfs_rw(trig_freq_enable, FRIE),
>>       tpda_trig_sysfs_rw(trig_flag_ts_enable, FLRIE),
>> diff --git a/drivers/hwtracing/coresight/coresight-tpda.h b/drivers/ 
>> hwtracing/coresight/coresight-tpda.h
>> index 1d2de50bb9f9..ef1ce2ce36a9 100644
>> --- a/drivers/hwtracing/coresight/coresight-tpda.h
>> +++ b/drivers/hwtracing/coresight/coresight-tpda.h
>> @@ -10,6 +10,7 @@
>>   #define TPDA_Pn_CR(n)        (0x004 + (n * 4))
>>   #define TPDA_FPID_CR        (0x084)
>>   #define TPDA_SYNCR        (0x08C)
>> +#define TPDA_FLUSH_CR        (0x090)
>>   /* Cross trigger global (all ports) flush request bit */
>>   #define TPDA_CR_FLREQ        BIT(0)
>>
>
Re: [PATCH v6 4/4] coresight: tpda: add sysfs node to flush specific port
Posted by Suzuki K Poulose 1 month, 2 weeks ago 
On 23/12/2025 02:16, Jie Gan wrote:
> 
> 
> On 12/22/2025 9:12 PM, Suzuki K Poulose wrote:
>> On 22/12/2025 06:02, Jie Gan wrote:
>>> From: Tao Zhang <tao.zhang@oss.qualcomm.com>
>>>
>>> Setting bit i in the TPDA_FLUSH_CR register initiates a flush request
>>> for port i, forcing the data to synchronize and be transmitted to the
>>> sink device.
>>>
>>> Signed-off-by: Tao Zhang <tao.zhang@oss.qualcomm.com>
>>> Reviewed-by: James Clark <james.clark@linaro.org>
>>> Co-developed-by: Jie Gan <jie.gan@oss.qualcomm.com>
>>> Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
>>> ---
>>>   .../ABI/testing/sysfs-bus-coresight-devices-tpda   |  7 ++++
>>>   drivers/hwtracing/coresight/coresight-tpda.c       | 40 +++++++++++ 
>>> + ++++++++++
>>>   drivers/hwtracing/coresight/coresight-tpda.h       |  1 +
>>>   3 files changed, 48 insertions(+)
>>>
>>> diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices- 
>>> tpda b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda
>>> index d359d90dca72..df8f03d4b573 100644
>>> --- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda
>>> +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda
>>> @@ -51,3 +51,10 @@ Description:
>>>           mode 0 - COUNT[11:0] value represents the approximate 
>>> number of bytes moved between two ASYNC packet requests
>>>           mode 1 - the bits COUNT[11:7] are used as a power of 2. for 
>>> example, we could insert an async packet every 8K
>>>                    data by writing a value 13 to the COUNT[11:7] field.
>>> +
>>> +What:        /sys/bus/coresight/devices/<tpda-name>/port_flush_req
>>> +Date:        December 2025
>>> +KernelVersion:    6.19
>>> +Contact:    Jinlong Mao <jinlong.mao@oss.qualcomm.com>, Tao Zhang 
>>> <tao.zhang@oss.qualcomm.com>, Jie Gan <jie.gan@oss.qualcomm.com>
>>> +Description:
>>> +        (RW) Configure the bit i to requests a flush operation of 
>>> port i on the TPDA.
>>
>> Does this have similar semantics as the "global_flush_req"  for "Read" ? 
> 
> Yes, global_flush_req triggers all ports at once, whereas this node 
> initiates a flush request for specific port(s).
> 
> For reading, we can check whether the flush request has completed.

Please document it as such.

Suzuki


> 
> Thanks,
> Jie
> 
>> i.e., the bit stays set until the request completes ? Otherwise, why 
>> isn't this Write only ?
>>
>> I don't see the point of "Reading" this value back.
>>
>> Suzuki
>>
>>> diff --git a/drivers/hwtracing/coresight/coresight-tpda.c b/drivers/ 
>>> hwtracing/coresight/coresight-tpda.c
>>> index 7baa8a0965d3..f79fea4fbb2c 100644
>>> --- a/drivers/hwtracing/coresight/coresight-tpda.c
>>> +++ b/drivers/hwtracing/coresight/coresight-tpda.c
>>> @@ -430,9 +430,49 @@ static ssize_t syncr_mode_store(struct device *dev,
>>>   }
>>>   static DEVICE_ATTR_RW(syncr_mode);
>>> +static ssize_t port_flush_req_show(struct device *dev,
>>> +                   struct device_attribute *attr,
>>> +                   char *buf)
>>> +{
>>> +    struct tpda_drvdata *drvdata = dev_get_drvdata(dev->parent);
>>> +    unsigned long val;
>>> +
>>> +    if (!drvdata->csdev->refcnt)
>>> +        return -EINVAL;
>>> +
>>> +    guard(spinlock)(&drvdata->spinlock);
>>> +    val = readl_relaxed(drvdata->base + TPDA_FLUSH_CR);
>>> +
>>> +    return sysfs_emit(buf, "0x%lx\n", val);
>>> +}
>>> +
>>> +static ssize_t port_flush_req_store(struct device *dev,
>>> +                    struct device_attribute *attr,
>>> +                    const char *buf,
>>> +                    size_t size)
>>> +{
>>> +    struct tpda_drvdata *drvdata = dev_get_drvdata(dev->parent);
>>> +    u32 val;
>>> +
>>> +    if (kstrtou32(buf, 0, &val))
>>> +        return -EINVAL;
>>> +
>>> +    if (!drvdata->csdev->refcnt || !val)
>>> +        return -EINVAL;
>>> +
>>> +    guard(spinlock)(&drvdata->spinlock);
>>> +    CS_UNLOCK(drvdata->base);
>>> +    writel_relaxed(val, drvdata->base + TPDA_FLUSH_CR);
>>> +    CS_LOCK(drvdata->base);
>>> +
>>> +    return size;
>>> +}
>>> +static DEVICE_ATTR_RW(port_flush_req);
>>> +
>>>   static struct attribute *tpda_attrs[] = {
>>>       &dev_attr_global_flush_req.attr,
>>>       &dev_attr_syncr_mode.attr,
>>> +    &dev_attr_port_flush_req.attr,
>>>       tpda_trig_sysfs_rw(freq_ts_enable, FREQTS),
>>>       tpda_trig_sysfs_rw(trig_freq_enable, FRIE),
>>>       tpda_trig_sysfs_rw(trig_flag_ts_enable, FLRIE),
>>> diff --git a/drivers/hwtracing/coresight/coresight-tpda.h b/drivers/ 
>>> hwtracing/coresight/coresight-tpda.h
>>> index 1d2de50bb9f9..ef1ce2ce36a9 100644
>>> --- a/drivers/hwtracing/coresight/coresight-tpda.h
>>> +++ b/drivers/hwtracing/coresight/coresight-tpda.h
>>> @@ -10,6 +10,7 @@
>>>   #define TPDA_Pn_CR(n)        (0x004 + (n * 4))
>>>   #define TPDA_FPID_CR        (0x084)
>>>   #define TPDA_SYNCR        (0x08C)
>>> +#define TPDA_FLUSH_CR        (0x090)
>>>   /* Cross trigger global (all ports) flush request bit */
>>>   #define TPDA_CR_FLREQ        BIT(0)
>>>
>>
>

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