[PATCH v8 09/13] coresight-tpdm: Add nodes for dsb edge control

Tao Zhang quic_taozha at quicinc.com
Fri Sep 1 09:01:28 PDT 2023


On 9/1/2023 10:07 PM, Suzuki K Poulose wrote:
> On 22/08/2023 06:26, Tao Zhang wrote:
>> Add the nodes to set value for DSB edge control and DSB edge
>> control mask. Each DSB subunit TPDM has maximum of n(n<16) EDCR
>> resgisters to configure edge control. DSB edge detection control
>> 00: Rising edge detection
>> 01: Falling edge detection
>> 10: Rising and falling edge detection (toggle detection)
>> And each DSB subunit TPDM has maximum of m(m<8) ECDMR registers to
>> configure mask. Eight 32 bit registers providing DSB interface
>> edge detection mask control.
>>
>> Add the nodes to configure DSB edge control and DSB edge control
>> mask. Each DSB subunit TPDM maximum of 256 edge detections can be
>> configured. The index and value sysfs files need to be paired and
>> written to order. The index sysfs file is to set the index number
>> of the edge detection which needs to be configured. And the value
>> sysfs file is to set the control or mask for the edge detection.
>> DSB edge detection control should be set as the following values.
>> 00: Rising edge detection
>> 01: Falling edge detection
>> 10: Rising and falling edge detection (toggle detection)
>> And DSB edge mask should be set as 0 or 1.
>> Each DSB subunit TPDM has maximum of n(n<16) EDCR resgisters to
>> configure edge control. And each DSB subunit TPDM has maximum of
>> m(m<8) ECDMR registers to configure mask.
>>
>> Add the nodes to read a set of the edge control value and mask
>> of the DSB in TPDM.
>>
>> Signed-off-by: Tao Zhang <quic_taozha at quicinc.com>
>> ---
>>   .../ABI/testing/sysfs-bus-coresight-devices-tpdm   |  51 ++++++
>>   drivers/hwtracing/coresight/coresight-tpdm.c       | 177 
>> ++++++++++++++++++++-
>>   drivers/hwtracing/coresight/coresight-tpdm.h       |  63 ++++++++
>>   3 files changed, 288 insertions(+), 3 deletions(-)
>>
>> diff --git 
>> a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm 
>> b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
>> index e17d1b4..097fdc4 100644
>> --- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
>> +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
>> @@ -57,3 +57,54 @@ Description:
>>           Bit[3] : Set to 0 for low performance mode.
>>                    Set to 1 for high performance mode.
>>           Bit[4:8] : Select byte lane for high performance mode.
>> +
>> +What: /sys/bus/coresight/devices/<tpdm-name>/dsb_edge/ctrl_idx
>> +Date:        March 2023
>> +KernelVersion    6.5
>
> s/6.5/6.7
Sure, I will update this in the next patch series.
>
>> +Contact:    Jinlong Mao (QUIC) <quic_jinlmao at quicinc.com>, Tao Zhang 
>> (QUIC) <quic_taozha at quicinc.com>
>> +Description:
>> +        (RW) Set/Get the index number of the edge detection for the DSB
>> +        subunit TPDM. Since there are at most 256 edge detections, this
>> +        value ranges from 0 to 255.
>> +
>> +What: /sys/bus/coresight/devices/<tpdm-name>/dsb_edge/ctrl_val
>> +Date:        March 2023
>> +KernelVersion    6.5
>
> same as above
>
>> +Contact:    Jinlong Mao (QUIC) <quic_jinlmao at quicinc.com>, Tao Zhang 
>> (QUIC) <quic_taozha at quicinc.com>
>> +Description:
>> +        Write a data to control the edge detection corresponding to
>> +        the index number. Before writing data to this sysfs file,
>> +        "ctrl_idx" should be written first to configure the index
>> +        number of the edge detection which needs to be controlled.
>> +
>> +        Accepts only one of the following values.
>> +        0 - Rising edge detection
>> +        1 - Falling edge detection
>> +        2 - Rising and falling edge detection (toggle detection)
>> +
>> +
>> +What: /sys/bus/coresight/devices/<tpdm-name>/dsb_edge/ctrl_mask
>> +Date:        March 2023
>> +KernelVersion    6.5
>> +Contact:    Jinlong Mao (QUIC) <quic_jinlmao at quicinc.com>, Tao Zhang 
>> (QUIC) <quic_taozha at quicinc.com>
>> +Description:
>> +        Write a data to mask the edge detection corresponding to the 
>> index
>> +        number. Before writing data to this sysfs file, "ctrl_idx" 
>> should
>> +        be written first to configure the index number of the edge 
>> detection
>> +        which needs to be masked.
>> +
>> +        Accepts only one of the 2 values -  0 or 1.
>> +
>> +What: /sys/bus/coresight/devices/<tpdm-name>/dsb_edge/edcr[0:15]
>> +Date:        March 2023
>> +KernelVersion    6.5
>> +Contact:    Jinlong Mao (QUIC) <quic_jinlmao at quicinc.com>, Tao Zhang 
>> (QUIC) <quic_taozha at quicinc.com>
>> +Description:
>> +        Read a set of the edge control value of the DSB in TPDM.
>
> Read edge control register n for edcr<n>.

In fact, we don't read the register directly through this sysfs file, 
but read the value

we set to be written to the registers. Do I still need to modify it here?

>
>> +
>> +What: /sys/bus/coresight/devices/<tpdm-name>/dsb_edge/edcmr[0:7]
>> +Date:        March 2023
>> +KernelVersion    6.5
>> +Contact:    Jinlong Mao (QUIC) <quic_jinlmao at quicinc.com>, Tao Zhang 
>> (QUIC) <quic_taozha at quicinc.com>
>> +Description:
>> +        Read a set of the edge control mask of the DSB in TPDM.
>> \ No newline at end of file
>> diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c 
>> b/drivers/hwtracing/coresight/coresight-tpdm.c
>> index 2424eb7..ba61e6a 100644
>> --- a/drivers/hwtracing/coresight/coresight-tpdm.c
>> +++ b/drivers/hwtracing/coresight/coresight-tpdm.c
>> @@ -21,6 +21,29 @@
>>     DEFINE_CORESIGHT_DEVLIST(tpdm_devs, "tpdm");
>>   +/* Read dataset array member with the index number */
>> +static ssize_t tpdm_simple_dataset_show(struct device *dev,
>> +               struct device_attribute *attr, char *buf)
>> +{
>> +    struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +    struct tpdm_dataset_attribute *tpdm_attr =
>> +        container_of(attr, struct tpdm_dataset_attribute, attr);
>> +
>> +    if (tpdm_attr->idx >= tpdm_attr->max)
>
> minor nit: See my comment on max below. We could skip max.
I will update this in the next patch series.
>
>> +        return -EINVAL;
>> +
>> +    switch (tpdm_attr->mem) {
>> +    case DSB_EDGE_CTRL:
>         if (tmp_attr->idx > TPDM_DSB_MAX_EDCR)
>             break;
>
>> +        return sysfs_emit(buf, "0x%x\n",
>> + drvdata->dsb->edge_ctrl[tpdm_attr->idx]);
>> +    case DSB_EDGE_CTRL_MASK:
>         if (tmp_attr->idx > TPDM_DSB_MAX_EDCMR)
>             break;
>
>> +        return sysfs_emit(buf, "0x%x\n",
>> + drvdata->dsb->edge_ctrl_mask[tpdm_attr->idx]);
>     }
>
>     return -EINVAL;
Why do we need to return this error code here?
>
>
>> +    default:
>> +        return -EINVAL;
>> +    }
>> +}
>> +
>>   static bool tpdm_has_dsb_dataset(struct tpdm_drvdata *drvdata)
>>   {
>>       return (drvdata->datasets & TPDM_PIDR0_DS_DSB);
>> @@ -71,7 +94,14 @@ static void set_dsb_mode(struct tpdm_drvdata 
>> *drvdata, u32 *val)
>>     static void tpdm_enable_dsb(struct tpdm_drvdata *drvdata)
>>   {
>> -    u32 val;
>> +    u32 val, i;
>> +
>> +    for (i = 0; i < TPDM_DSB_MAX_EDCR; i++)
>> +        writel_relaxed(drvdata->dsb->edge_ctrl[i],
>> +               drvdata->base + TPDM_DSB_EDCR(i));
>> +    for (i = 0; i < TPDM_DSB_MAX_EDCMR; i++)
>> +        writel_relaxed(drvdata->dsb->edge_ctrl_mask[i],
>> +               drvdata->base + TPDM_DSB_EDCMR(i));
>>         val = readl_relaxed(drvdata->base + TPDM_DSB_TIER);
>>       /* Set trigger timestamp */
>> @@ -296,6 +326,109 @@ static ssize_t dsb_mode_store(struct device *dev,
>>   }
>>   static DEVICE_ATTR_RW(dsb_mode);
>>   +static ssize_t ctrl_idx_show(struct device *dev,
>> +                struct device_attribute *attr,
>> +                char *buf)
>> +{
>> +    struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +
>> +    return sysfs_emit(buf, "%u\n",
>> +            (unsigned int)drvdata->dsb->edge_ctrl_idx);
>> +}
>> +
>> +/*
>> + * The EDCR registers can include up to 16 32-bit registers, and each
>> + * one can be configured to control up to 16 edge detections(2 bits
>> + * control one edge detection). So a total 256 edge detections can be
>> + * configured. This function provides a way to set the index number of
>> + * the edge detection which needs to be configured.
>> + */
>> +static ssize_t ctrl_idx_store(struct device *dev,
>> +                struct device_attribute *attr,
>> +                const char *buf,
>> +                size_t size)
>> +{
>> +    struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +    unsigned long val;
>> +
>> +    if ((kstrtoul(buf, 0, &val)) || (val >= TPDM_DSB_MAX_LINES))
>> +        return -EINVAL;
>> +
>> +    spin_lock(&drvdata->spinlock);
>> +    drvdata->dsb->edge_ctrl_idx = val;
>> +    spin_unlock(&drvdata->spinlock);
>> +
>> +    return size;
>> +}
>> +static DEVICE_ATTR_RW(ctrl_idx);
>> +
>> +/*
>> + * This function is used to control the edge detection according
>> + * to the index number that has been set.
>> + * "edge_ctrl" should be one of the following values.
>> + * 0 - Rising edge detection
>> + * 1 - Falling edge detection
>> + * 2 - Rising and falling edge detection (toggle detection)
>> + */
>> +static ssize_t ctrl_val_store(struct device *dev,
>> +                struct device_attribute *attr,
>> +                const char *buf,
>> +                size_t size)
>> +{
>> +    struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +    unsigned long val, edge_ctrl;
>> +    int reg;
>> +
>> +    if ((kstrtoul(buf, 0, &edge_ctrl)) || (edge_ctrl > 0x2))
>> +        return -EINVAL;
>> +
>> +    spin_lock(&drvdata->spinlock);
>> +    /*
>> +     * There are 2 bit per DSB Edge Control line.
>> +     * Thus we have 16 lines in a 32bit word.
>> +     */
>> +    reg = EDCR_TO_WORD_IDX(drvdata->dsb->edge_ctrl_idx);
>> +    val = drvdata->dsb->edge_ctrl[reg];
>> +    val &= ~EDCR_TO_WORD_MASK(drvdata->dsb->edge_ctrl_idx);
>> +    val |= EDCR_TO_WORD_VAL(edge_ctrl, drvdata->dsb->edge_ctrl_idx);
>> +    drvdata->dsb->edge_ctrl[reg] = val;
>> +    spin_unlock(&drvdata->spinlock);
>> +
>> +    return size;
>> +}
>> +static DEVICE_ATTR_WO(ctrl_val);
>> +
>> +static ssize_t ctrl_mask_store(struct device *dev,
>> +                  struct device_attribute *attr,
>> +                  const char *buf,
>> +                  size_t size)
>> +{
>> +    struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +    unsigned long val;
>> +    u32 set;
>> +    int reg;
>> +
>> +    if ((kstrtoul(buf, 0, &val)) || (val & ~1UL))
>> +        return -EINVAL;
>> +
>> +    spin_lock(&drvdata->spinlock);
>> +    /*
>> +     * There is 1 bit per DSB Edge Control Mark line.
>> +     * Thus we have 32 lines in a 32bit word.
>> +     */
>> +    reg = EDCMR_TO_WORD_IDX(drvdata->dsb->edge_ctrl_idx);
>> +    set = drvdata->dsb->edge_ctrl_mask[reg];
>> +    if (val)
>> +        set |= BIT(EDCMR_TO_WORD_SHIFT(drvdata->dsb->edge_ctrl_idx));
>> +    else
>> +        set &= ~BIT(EDCMR_TO_WORD_SHIFT(drvdata->dsb->edge_ctrl_idx));
>> +    drvdata->dsb->edge_ctrl_mask[reg] = set;
>> +    spin_unlock(&drvdata->spinlock);
>> +
>> +    return size;
>> +}
>> +static DEVICE_ATTR_WO(ctrl_mask);
>> +
>>   static ssize_t dsb_trig_type_show(struct device *dev,
>>             struct device_attribute *attr, char *buf)
>>   {
>> @@ -367,6 +500,37 @@ static ssize_t dsb_trig_ts_store(struct device 
>> *dev,
>>   }
>>   static DEVICE_ATTR_RW(dsb_trig_ts);
>>   +static struct attribute *tpdm_dsb_edge_attrs[] = {
>> +    &dev_attr_ctrl_idx.attr,
>> +    &dev_attr_ctrl_val.attr,
>> +    &dev_attr_ctrl_mask.attr,
>> +    DSB_EDGE_CTRL_ATTR(0),
>> +    DSB_EDGE_CTRL_ATTR(1),
>> +    DSB_EDGE_CTRL_ATTR(2),
>> +    DSB_EDGE_CTRL_ATTR(3),
>> +    DSB_EDGE_CTRL_ATTR(4),
>> +    DSB_EDGE_CTRL_ATTR(5),
>> +    DSB_EDGE_CTRL_ATTR(6),
>> +    DSB_EDGE_CTRL_ATTR(7),
>> +    DSB_EDGE_CTRL_ATTR(8),
>> +    DSB_EDGE_CTRL_ATTR(9),
>> +    DSB_EDGE_CTRL_ATTR(10),
>> +    DSB_EDGE_CTRL_ATTR(11),
>> +    DSB_EDGE_CTRL_ATTR(12),
>> +    DSB_EDGE_CTRL_ATTR(13),
>> +    DSB_EDGE_CTRL_ATTR(14),
>> +    DSB_EDGE_CTRL_ATTR(15),
>> +    DSB_EDGE_CTRL_MASK_ATTR(0),
>> +    DSB_EDGE_CTRL_MASK_ATTR(1),
>> +    DSB_EDGE_CTRL_MASK_ATTR(2),
>> +    DSB_EDGE_CTRL_MASK_ATTR(3),
>> +    DSB_EDGE_CTRL_MASK_ATTR(4),
>> +    DSB_EDGE_CTRL_MASK_ATTR(5),
>> +    DSB_EDGE_CTRL_MASK_ATTR(6),
>> +    DSB_EDGE_CTRL_MASK_ATTR(7),
>> +    NULL,
>> +};
>> +
>>   static struct attribute *tpdm_dsb_attrs[] = {
>>       &dev_attr_dsb_mode.attr,
>>       &dev_attr_dsb_trig_ts.attr,
>> @@ -374,14 +538,21 @@ static struct attribute *tpdm_dsb_attrs[] = {
>>       NULL,
>>   };
>>   -static struct attribute_group tpdm_dsb_attr_grp = {
>> +static struct attribute_group tpdm_dsb_attrs_grp = {
>>       .attrs = tpdm_dsb_attrs,
>>       .is_visible = tpdm_dsb_is_visible,
>>   };
>>   +static struct attribute_group tpdm_dsb_edge_grp = {
>> +    .attrs = tpdm_dsb_edge_attrs,
>> +    .is_visible = tpdm_dsb_is_visible,
>> +    .name = "dsb_edge",
>> +};
>> +
>>   static const struct attribute_group *tpdm_attr_grps[] = {
>>       &tpdm_attr_grp,
>> -    &tpdm_dsb_attr_grp,
>> +    &tpdm_dsb_attrs_grp,
>> +    &tpdm_dsb_edge_grp,
>>       NULL,
>>   };
>>   diff --git a/drivers/hwtracing/coresight/coresight-tpdm.h 
>> b/drivers/hwtracing/coresight/coresight-tpdm.h
>> index f57c9fe..9736e00 100644
>> --- a/drivers/hwtracing/coresight/coresight-tpdm.h
>> +++ b/drivers/hwtracing/coresight/coresight-tpdm.h
>> @@ -12,6 +12,8 @@
>>   /* DSB Subunit Registers */
>>   #define TPDM_DSB_CR        (0x780)
>>   #define TPDM_DSB_TIER        (0x784)
>> +#define TPDM_DSB_EDCR(n)    (0x808 + (n * 4))
>> +#define TPDM_DSB_EDCMR(n)    (0x848 + (n * 4))
>>     /* Enable bit for DSB subunit */
>>   #define TPDM_DSB_CR_ENA        BIT(0)
>> @@ -37,6 +39,16 @@
>>   /* High performance mode */
>>   #define TPDM_DSB_MODE_HPBYTESEL(val)    (val & GENMASK(8, 4))
>>   +#define EDCRS_PER_WORD                16
>> +#define EDCR_TO_WORD_IDX(r)            ((r) / EDCRS_PER_WORD)
>> +#define EDCR_TO_WORD_SHIFT(r)        ((r % EDCRS_PER_WORD) * 2)
>> +#define EDCR_TO_WORD_VAL(val, r)    (val << EDCR_TO_WORD_SHIFT(r))
>> +#define EDCR_TO_WORD_MASK(r)        EDCR_TO_WORD_VAL(0x3, r)
>> +
>> +#define EDCMRS_PER_WORD                32
>> +#define EDCMR_TO_WORD_IDX(r)        ((r) / EDCMRS_PER_WORD)
>> +#define EDCMR_TO_WORD_SHIFT(r)        ((r) % EDCMRS_PER_WORD)
>> +
>>   /* TPDM integration test registers */
>>   #define TPDM_ITATBCNTRL        (0xEF0)
>>   #define TPDM_ITCNTRL        (0xF00)
>> @@ -63,14 +75,44 @@
>>   #define TPDM_PIDR0_DS_IMPDEF    BIT(0)
>>   #define TPDM_PIDR0_DS_DSB    BIT(1)
>>   +#define TPDM_DSB_MAX_LINES    256
>> +/* MAX number of EDCR registers */
>> +#define TPDM_DSB_MAX_EDCR    16
>> +/* MAX number of EDCMR registers */
>> +#define TPDM_DSB_MAX_EDCMR    8
>> +
>> +#define tpdm_simple_dataset_ro(name, mem, idx, max) \
>
> Do we need max ? The mem itself is enough to help you
> choose the max ? See my comment above.
I will update this in the next patch series.
>
>> +    (&((struct tpdm_dataset_attribute[]) {            \
>> +       {                                \
>> +        __ATTR(name, 0444, tpdm_simple_dataset_show, NULL), \
>> +        mem,                            \
>> +        idx,                            \
>> +        max,                            \
>> +       }                                \
>> +    })[0].attr.attr)
>> +
>> +#define DSB_EDGE_CTRL_ATTR(nr)                    \
>> +        tpdm_simple_dataset_ro(edcr##nr,        \
>> +        DSB_EDGE_CTRL, nr, TPDM_DSB_MAX_EDCR)
>> +
>> +#define DSB_EDGE_CTRL_MASK_ATTR(nr)                \
>> +        tpdm_simple_dataset_ro(edcmr##nr,        \
>> +        DSB_EDGE_CTRL_MASK, nr, TPDM_DSB_MAX_EDCMR)
>> +
>>   /**
>>    * struct dsb_dataset - specifics associated to dsb dataset
>>    * @mode:             DSB programming mode
>> + * @edge_ctrl_idx     Index number of the edge control
>> + * @edge_ctrl:        Save value for edge control
>> + * @edge_ctrl_mask:   Save value for edge control mask
>>    * @trig_ts:          Enable/Disable trigger timestamp.
>>    * @trig_type:        Enable/Disable trigger type.
>>    */
>>   struct dsb_dataset {
>>       u32                mode;
>> +    u32                edge_ctrl_idx;
>> +    u32                edge_ctrl[TPDM_DSB_MAX_EDCR] > + 
>> u32                edge_ctrl_mask[TPDM_DSB_MAX_EDCMR];
>>       bool            trig_ts;
>>       bool            trig_type;
>>   };
>> @@ -96,4 +138,25 @@ struct tpdm_drvdata {
>>       struct dsb_dataset    *dsb;
>>   };
>>   +/* Enumerate members of various datasets */
>> +enum dataset_mem {
>> +    DSB_EDGE_CTRL,
>> +    DSB_EDGE_CTRL_MASK,
>> +};
>> +
>> +/**
>> + * struct tpdm_dataset_attribute - Record the member variables and
>> + * index number of datasets that need to be operated by sysfs file
>> + * @attr:       The device attribute
>> + * @mem:        The member in the dataset data structure
>> + * @idx:        The index number of the array data
>> + * @max:        The maximal number of the array data
>
> As mentioned above, you could remove this.

Sure, I will update this in the next patch series.


Best,

Tao

>
> Suzuki
>
>> + */
>> +struct tpdm_dataset_attribute {
>> +    struct device_attribute attr;
>> +    enum dataset_mem mem;
>> +    u32 idx;
>> +    u32 max;
>> +};
>> +
>>   #endif  /* _CORESIGHT_CORESIGHT_TPDM_H */
>



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