[PATCH v5 1/3] coresight: tpda: add sysfs nodes for tpda cross-trigger configuration

Jie Gan jie.gan at oss.qualcomm.com
Fri Dec 19 04:19:30 PST 2025



On 12/19/2025 6:22 PM, Suzuki K Poulose wrote:
> On 19/12/2025 10:04, Jie Gan wrote:
>> From: Tao Zhang <tao.zhang at oss.qualcomm.com>
>>
>> Introduce sysfs nodes to configure cross-trigger parameters for TPDA.
>> These registers define the characteristics of cross-trigger packets,
>> including generation frequency and flag values.
>>
>> Signed-off-by: Tao Zhang <tao.zhang at oss.qualcomm.com>
>> Reviewed-by: James Clark <james.clark at linaro.org>
>> Co-developed-by: Jie Gan <jie.gan at oss.qualcomm.com>
>> Signed-off-by: Jie Gan <jie.gan at oss.qualcomm.com>
>> ---
>>   .../ABI/testing/sysfs-bus-coresight-devices-tpda   |  43 +++++++
>>   drivers/hwtracing/coresight/coresight-tpda.c       | 138 +++++++++++ 
>> +++++++++-
>>   drivers/hwtracing/coresight/coresight-tpda.h       |  69 ++++++++++-
>>   3 files changed, 243 insertions(+), 7 deletions(-)
>>
>> diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices- 
>> tpda b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda
>> new file mode 100644
>> index 000000000000..a7855922328e
>> --- /dev/null
>> +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpda
>> @@ -0,0 +1,43 @@
>> +What:        /sys/bus/coresight/devices/<tpda-name>/global_cr/ 
>> trig_async_enable
>> +Date:        December 2025
>> +KernelVersion:    6.19
>> +Contact:    Jinlong Mao <jinlong.mao at oss.qualcomm.com>, Tao Zhang 
>> <tao.zhang at oss.qualcomm.com>, Jie Gan <jie.gan at oss.qualcomm.com>
>> +Description:
>> +        (RW) Enable/disable cross trigger synchronization sequence 
>> interface.
>> +
>> +What:        /sys/bus/coresight/devices/<tpda-name>/global_cr/ 
>> trig_flag_ts_enable
>> +Date:        December 2025
>> +KernelVersion:    6.19
>> +Contact:    Jinlong Mao <jinlong.mao at oss.qualcomm.com>, Tao Zhang 
>> <tao.zhang at oss.qualcomm.com>, Jie Gan <jie.gan at oss.qualcomm.com>
>> +Description:
>> +        (RW) Enable/disable cross trigger FLAG packet request interface.
>> +
>> +What:        /sys/bus/coresight/devices/<tpda-name>/global_cr/ 
>> trig_freq_enable
>> +Date:        December 2025
>> +KernelVersion:    6.19
>> +Contact:    Jinlong Mao <jinlong.mao at oss.qualcomm.com>, Tao Zhang 
>> <tao.zhang at oss.qualcomm.com>, Jie Gan <jie.gan at oss.qualcomm.com>
>> +Description:
>> +        (RW) Enable/disable cross trigger FREQ packet request interface.
>> +
>> +What:        /sys/bus/coresight/devices/<tpda-name>/global_cr/ 
>> freq_ts_enable
>> +Date:        December 2025
>> +KernelVersion:    6.19
>> +Contact:    Jinlong Mao <jinlong.mao at oss.qualcomm.com>, Tao Zhang 
>> <tao.zhang at oss.qualcomm.com>, Jie Gan <jie.gan at oss.qualcomm.com>
>> +Description:
>> +        (RW) Enable/disable the timestamp for all FREQ packets.
>> +
>> +What:        /sys/bus/coresight/devices/<tpda-name>/global_cr/ 
>> global_flush_req
>> +Date:        December 2025
>> +KernelVersion:    6.19
>> +Contact:    Jinlong Mao <jinlong.mao at oss.qualcomm.com>, Tao Zhang 
>> <tao.zhang at oss.qualcomm.com>, Jie Gan <jie.gan at oss.qualcomm.com>
>> +Description:
>> +        (RW) Set global (all ports) flush request bit. The bit 
>> remains set until a
>> +        global flush request sequence completes.
>> +
>> +What:        /sys/bus/coresight/devices/<tpda-name>/global_cr/ 
>> cmbchan_mode
>> +Date:        December 2025
>> +KernelVersion:    6.19
>> +Contact:    Jinlong Mao <jinlong.mao at oss.qualcomm.com>, Tao Zhang 
>> <tao.zhang at oss.qualcomm.com>, Jie Gan <jie.gan at oss.qualcomm.com>
>> +Description:
>> +        (RW) Configure the CMB/MCMB channel mode for all enabled ports.
>> +        Value 0 means raw channel mapping mode. Value 1 means channel 
>> pair marking mode.
>> diff --git a/drivers/hwtracing/coresight/coresight-tpda.c b/drivers/ 
>> hwtracing/coresight/coresight-tpda.c
>> index 3a3825d27f86..d25a8bcfb3d4 100644
>> --- a/drivers/hwtracing/coresight/coresight-tpda.c
>> +++ b/drivers/hwtracing/coresight/coresight-tpda.c
>> @@ -137,12 +137,32 @@ static int tpda_get_element_size(struct 
>> tpda_drvdata *drvdata,
>>   /* Settings pre enabling port control register */
>>   static void tpda_enable_pre_port(struct tpda_drvdata *drvdata)
>>   {
>> -    u32 val;
>> +    u32 val = 0;
>> -    val = readl_relaxed(drvdata->base + TPDA_CR);
>> -    val &= ~TPDA_CR_ATID;
>>       val |= FIELD_PREP(TPDA_CR_ATID, drvdata->atid);
>> +    if (drvdata->trig_async)
>> +        val |= TPDA_CR_SRIE;
>> +
>> +    if (drvdata->trig_flag_ts)
>> +        val |= TPDA_CR_FLRIE;
>> +
>> +    if (drvdata->trig_freq)
>> +        val |= TPDA_CR_FRIE;
>> +
>> +    if (drvdata->freq_ts)
>> +        val |= TPDA_CR_FREQTS;
>> +
>> +    if (drvdata->cmbchan_mode)
>> +        val |= TPDA_CR_CMBCHANMODE;
>> +
>>       writel_relaxed(val, drvdata->base + TPDA_CR);
>> +
>> +    /*
>> +     * If FLRIE bit is set, set the master and channel
>> +     * id as zero
>> +     */
>> +    if (drvdata->trig_flag_ts)
>> +        writel_relaxed(0x0, drvdata->base + TPDA_FPID_CR);
>>   }
>>   static int tpda_enable_port(struct tpda_drvdata *drvdata, int port)
>> @@ -258,6 +278,116 @@ static const struct coresight_ops tpda_cs_ops = {
>>       .link_ops    = &tpda_link_ops,
>>   };
>> +/* Read cross-trigger register member */
>> +static ssize_t tpda_trig_sysfs_show(struct device *dev,
>> +                    struct device_attribute *attr,
>> +                    char *buf)
>> +{
>> +    struct tpda_trig_sysfs_attribute *tpda_attr =
>> +        container_of(attr, struct tpda_trig_sysfs_attribute, attr);
>> +    struct tpda_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +    unsigned long val;
>> +
>> +    guard(spinlock)(&drvdata->spinlock);
>> +    switch (tpda_attr->mem) {
>> +    case FLREQ:
>> +        if (!drvdata->csdev->refcnt)
>> +            return -EINVAL;
>> +
>> +        val = readl_relaxed(drvdata->base + TPDA_CR);
>> +        /* read global flush request bit only */
>> +        val &= TPDA_CR_FLREQ;
>> +        return sysfs_emit(buf, "%lu\n", val);
>> +    case FREQTS:
>> +        return sysfs_emit(buf, "%u\n", (unsigned int)drvdata->freq_ts);
>> +    case FRIE:
>> +        return sysfs_emit(buf, "%u\n", (unsigned int)drvdata- 
>> >trig_freq);
>> +    case FLRIE:
>> +        return sysfs_emit(buf, "%u\n", (unsigned int)drvdata- 
>> >trig_flag_ts);
>> +    case SRIE:
>> +        return sysfs_emit(buf, "%u\n", (unsigned int)drvdata- 
>> >trig_async);
>> +    case CMBCHANMODE:
>> +        return sysfs_emit(buf, "%u\n", (unsigned int)drvdata- 
>> >cmbchan_mode);
>> +
>> +    }
>> +    return -EINVAL;
>> +}
>> +
>> +static ssize_t tpda_trig_sysfs_store(struct device *dev,
>> +                     struct device_attribute *attr,
>> +                     const char *buf,
>> +                     size_t size)
>> +{
>> +    struct tpda_trig_sysfs_attribute *tpda_attr =
>> +        container_of(attr, struct tpda_trig_sysfs_attribute, attr);
>> +    struct tpda_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +    ssize_t ret = -EINVAL;
>    +    unsigned long val;
>> +
>> +    if (kstrtoul(buf, 0, &val))
>> +        return ret;
> 
>          return -EINVAL;
> 
>> +
>> +    guard(spinlock)(&drvdata->spinlock);
>> +    switch (tpda_attr->mem) {
>> +    case FLREQ:
>> +        if (!drvdata->csdev->refcnt || !val)
>> +            return ret;
>              return -EINVAL;
> 
>> +
>> +        val = readl_relaxed(drvdata->base + TPDA_CR);
> 
> CS_UNLOCK before readl ? I didn't mean the global_flush_req to be
> unified with the rest. Obviously it has different access semantics.

We dont need CS_UNLOCK for reading a register.

The global_flush_req is supposing access when the tpda is enabled. I 
will put it in a separate patch with detail description.

> 
> 
>> +        /* set global flush request bit */
>> +        val |= TPDA_CR_FLREQ;
>> +        CS_UNLOCK(drvdata->base);
>> +        writel_relaxed(val, drvdata->base + TPDA_CR);
>> +        CS_LOCK(drvdata->base);
>> +        ret = size;
> 
> Please remove this from all the cases and explicitly return -EINVAL in
> the error cases.

Will fix it.

> 
>> +        break;
>> +    case FREQTS:
>> +        drvdata->freq_ts = !!val;
>> +        ret = size;
>> +        break;
>> +    case FRIE:
>> +        drvdata->trig_freq = !!val;
>> +        ret = size;
>> +        break;
>> +    case FLRIE:
>> +        drvdata->trig_flag_ts = !!val;
>> +        ret = size;
>> +        break;
>> +    case SRIE:
>> +        drvdata->trig_async = !!val;
>> +        ret = size;
>> +        break;
>> +    case CMBCHANMODE:
>> +        drvdata->cmbchan_mode = !!val;
>> +        ret = size;
>> +        break;
>> +    default:
>          return -EINVAL;
> 
>> +        break;
>> +    }
>> +
> 
> 
>> +    return ret;
> 
>      return size;
> 
>> +}
>> +
>> +static struct attribute *tpda_global_cr_attrs[] = {
>> +    tpda_trig_sysfs_rw(global_flush_req, FLREQ),
>> +    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),
>> +    tpda_trig_sysfs_rw(trig_async_enable, SRIE),
>> +    tpda_trig_sysfs_rw(cmbchan_mode, CMBCHANMODE),
>> +    NULL,
>> +};
>> +
>> +static struct attribute_group tpda_global_cr_attr_grp = {
>> +    .attrs    = tpda_global_cr_attrs,
>> +    .name    = "global_cr",
>> +};
>> +
>> +static const struct attribute_group *tpda_attr_grps[] = {
>> +    &tpda_global_cr_attr_grp,
>> +    NULL,
>> +};
>> +
>>   static int tpda_init_default_data(struct tpda_drvdata *drvdata)
>>   {
>>       int atid;
>> @@ -273,6 +403,7 @@ static int tpda_init_default_data(struct 
>> tpda_drvdata *drvdata)
>>           return atid;
>>       drvdata->atid = atid;
>> +    drvdata->freq_ts = true;
>>       return 0;
>>   }
>> @@ -316,6 +447,7 @@ static int tpda_probe(struct amba_device *adev, 
>> const struct amba_id *id)
>>       desc.ops = &tpda_cs_ops;
>>       desc.pdata = adev->dev.platform_data;
>>       desc.dev = &adev->dev;
>> +    desc.groups = tpda_attr_grps;
>>       desc.access = CSDEV_ACCESS_IOMEM(base);
>>       drvdata->csdev = coresight_register(&desc);
>>       if (IS_ERR(drvdata->csdev))
>> diff --git a/drivers/hwtracing/coresight/coresight-tpda.h b/drivers/ 
>> hwtracing/coresight/coresight-tpda.h
>> index c6af3d2da3ef..8a075cfbc3cc 100644
>> --- a/drivers/hwtracing/coresight/coresight-tpda.h
>> +++ b/drivers/hwtracing/coresight/coresight-tpda.h
>> @@ -1,6 +1,6 @@
>>   /* SPDX-License-Identifier: GPL-2.0 */
>>   /*
>> - * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights 
>> reserved.
>> + * Copyright (c) 2023,2025 Qualcomm Innovation Center, Inc. All 
>> rights reserved.
>>    */
>>   #ifndef _CORESIGHT_CORESIGHT_TPDA_H
>> @@ -8,6 +8,30 @@
>>   #define TPDA_CR            (0x000)
>>   #define TPDA_Pn_CR(n)        (0x004 + (n * 4))
>> +#define TPDA_FPID_CR        (0x084)
>> +
>> +/* Cross trigger Global (all ports) flush request bit */
>> +#define TPDA_CR_FLREQ        BIT(0)
>> +/* Cross trigger FREQ packets timestamp bit */
>> +#define TPDA_CR_FREQTS        BIT(2)
>> +/* Cross trigger FREQ packet request bit */
>> +#define TPDA_CR_FRIE        BIT(3)
>> +/* Cross trigger FLAG packet request interface bit */
>> +#define TPDA_CR_FLRIE        BIT(4)
>> +/* Cross trigger synchronization bit */
>> +#define TPDA_CR_SRIE        BIT(5)
>> +/* Bits 6 ~ 12 is for atid value */
>> +#define TPDA_CR_ATID        GENMASK(12, 6)
>> +/* Bits 13 ~ 19 is for mid value */
>> +/* Assign a unique master ID to identify the TPDA device */
>> +#define TPDA_CR_MID        GENMASK(19, 13)
> 
> Where do we use this ? Does this need to be preserved ?
> Is this programmable ?
> 

We havent usage of this field. I will remove it in next version.

Thanks,
Jie

> Suzuki
> 
>> +/*
>> + * Channel mode bit of the packetization of CMB/MCB traffic
>> + * 0 - raw channel mapping mode
>> + * 1 - channel pair marking mode
>> + */
>> +#define TPDA_CR_CMBCHANMODE    BIT(20)
>> +
>>   /* Aggregator port enable bit */
>>   #define TPDA_Pn_CR_ENA        BIT(0)
>>   /* Aggregator port CMB data set element size bit */
>> @@ -17,9 +41,6 @@
>>   #define TPDA_MAX_INPORTS    32
>> -/* Bits 6 ~ 12 is for atid value */
>> -#define TPDA_CR_ATID        GENMASK(12, 6)
>> -
>>   /**
>>    * struct tpda_drvdata - specifics associated to an TPDA component
>>    * @base:       memory mapped base address for this component.
>> @@ -29,6 +50,11 @@
>>    * @enable:     enable status of the component.
>>    * @dsb_esize   Record the DSB element size.
>>    * @cmb_esize   Record the CMB element size.
>> + * @trig_async:    Enable/disable cross trigger synchronization 
>> sequence interface.
>> + * @trig_flag_ts: Enable/disable cross trigger FLAG packet request 
>> interface.
>> + * @trig_freq:    Enable/disable cross trigger FREQ packet request 
>> interface.
>> + * @freq_ts:    Enable/disable the timestamp for all FREQ packets.
>> + * @cmbchan_mode: Configure the CMB/MCMB channel mode.
>>    */
>>   struct tpda_drvdata {
>>       void __iomem        *base;
>> @@ -38,6 +64,41 @@ struct tpda_drvdata {
>>       u8            atid;
>>       u32            dsb_esize;
>>       u32            cmb_esize;
>> +    bool            trig_async;
>> +    bool            trig_flag_ts;
>> +    bool            trig_freq;
>> +    bool            freq_ts;
>> +    bool            cmbchan_mode;
>> +};
>> +
>> +/* Enumerate members of global control register(cr) */
>> +enum tpda_cr_mem {
>> +    FLREQ,
>> +    FREQTS,
>> +    FRIE,
>> +    FLRIE,
>> +    SRIE,
>> +    CMBCHANMODE
>> +};
>> +
>> +/**
>> + * struct tpda_trig_sysfs_attribute - Record the member variables of 
>> cross
>> + * trigger register that need to be operated by sysfs file
>> + * @attr:    The device attribute
>> + * @mem:    The member in the control register data structure
>> + */
>> +struct tpda_trig_sysfs_attribute {
>> +    struct device_attribute attr;
>> +    enum tpda_cr_mem mem;
>>   };
>> +#define tpda_trig_sysfs_rw(name, mem)                \
>> +    (&((struct tpda_trig_sysfs_attribute[]) {        \
>> +       {                            \
>> +        __ATTR(name, 0644, tpda_trig_sysfs_show,    \
>> +        tpda_trig_sysfs_store),                \
>> +        mem,                        \
>> +       }                            \
>> +       })[0].attr.attr)
>> +
>>   #endif  /* _CORESIGHT_CORESIGHT_TPDA_H */
>>
> 




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