Re: [PATCH v7 09/13] coresight-tpdm: Add nodes for dsb edge control

[Tao Zhang <quic_taozha@quicinc.com>]

On 8/7/2023 5:24 PM, Suzuki K Poulose wrote:
> On 25/07/2023 08:15, 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.
>>
>> Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
>> ---
>>   .../ABI/testing/sysfs-bus-coresight-devices-tpdm   |  39 +++++
>>   drivers/hwtracing/coresight/coresight-tpdm.c       | 158 
>> ++++++++++++++++++++-
>>   drivers/hwtracing/coresight/coresight-tpdm.h       |  30 +++-
>>   3 files changed, 223 insertions(+), 4 deletions(-)
>>
>> diff --git 
>> a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm 
>> b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
>> index 2a82cd0..a4550c5 100644
>> --- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
>> +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
>> @@ -60,3 +60,42 @@ 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
>> +Contact:    Jinlong Mao (QUIC) <quic_jinlmao@quicinc.com>, Tao Zhang 
>> (QUIC) <quic_taozha@quicinc.com>
>> +Description:
>> +        Read/Write 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
>> +Contact:    Jinlong Mao (QUIC) <quic_jinlmao@quicinc.com>, Tao Zhang 
>> (QUIC) <quic_taozha@quicinc.com>
>> +Description:
>> +        Read a set of the edge control registers of the DSB in TPDM.
>> +        Write a data to control the edge detection corresponding to
>> +        the index number. Before writing data to this sysfs file,
>> +        "dsb_edge_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@quicinc.com>, Tao Zhang 
>> (QUIC) <quic_taozha@quicinc.com>
>> +Description:
>> +        Read a set of the edge control mask registers of the DSB in 
>> TPDM.
>> +        Write a data to mask the edge detection corresponding to the 
>> index
>> +        number. Before writing data to this sysfs file, 
>> "dsb_edge_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.
>> \ No newline at end of file
>> diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c 
>> b/drivers/hwtracing/coresight/coresight-tpdm.c
>> index c38760b..98fd6ab 100644
>> --- a/drivers/hwtracing/coresight/coresight-tpdm.c
>> +++ b/drivers/hwtracing/coresight/coresight-tpdm.c
>> @@ -71,7 +71,14 @@ static void set_dsb_perf_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 */
>> @@ -302,6 +309,152 @@ static ssize_t dsb_mode_store(struct device *dev,
>>   }
>>   static DEVICE_ATTR_RW(dsb_mode);
>>   +static ssize_t dsb_edge_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 dsb_edge_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(dsb_edge_ctrl_idx);
>> +
>> +static ssize_t dsb_edge_ctrl_val_show(struct device *dev,
>> +                       struct device_attribute *attr,
>> +                       char *buf)
>> +{
>> +    struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +    ssize_t size = 0;
>> +    unsigned long bytes;
>> +    int i;
>> +
>> +    spin_lock(&drvdata->spinlock);
>> +    for (i = 0; i < TPDM_DSB_MAX_EDCR; i++) {
>> +        bytes = sysfs_emit_at(buf, size,
>> +                  "Val:0x%x\n", drvdata->dsb->edge_ctrl[i]);
>> +        if (bytes <= 0)
>> +            break;
>> +        size += bytes;
>> +    }
>> +    spin_unlock(&drvdata->spinlock);
>> +    return size;
>> +}
>> +
>> +/*
>> + * 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 dsb_edge_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, mask, 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);
>> +    mask = EDCR_TO_WORD_MASK(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_RW(dsb_edge_ctrl_val);
>> +
>> +static ssize_t dsb_edge_ctrl_mask_show(struct device *dev,
>> +                        struct device_attribute *attr,
>> +                        char *buf)
>> +{
>> +    struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
>> +    ssize_t size = 0;
>> +    unsigned long bytes;
>> +    int i;
>> +
>> +    spin_lock(&drvdata->spinlock);
>> +    for (i = 0; i < TPDM_DSB_MAX_EDCMR; i++) {
>> +        bytes = sysfs_emit_at(buf, size,
>> +                  "Val:0x%x\n", drvdata->dsb->edge_ctrl_mask[i]);
>> +        if (bytes <= 0)
>> +            break;
>> +        size += bytes;
>> +    }
>> +    spin_unlock(&drvdata->spinlock);
>> +    return size;
>> +}
>> +
>> +static ssize_t dsb_edge_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;
>
>
> drivers/hwtracing/coresight/coresight-tpdm.c: In function 
> ‘dsb_edge_ctrl_mask_store’:
> drivers/hwtracing/coresight/coresight-tpdm.c:449:2: error: this ‘else’ 
> clause does not guard... [-Werror=misleading-indentation]
>   else
>   ^~~~
> drivers/hwtracing/coresight/coresight-tpdm.c:451:3: note: ...this 
> statement, but the latter is misleadingly indented as if it were 
> guarded by the ‘else’
>    drvdata->dsb->edge_ctrl_mask[reg] = set;
>    ^~~~~~~
> cc1: all warnings being treated as errors
> make[4]: *** [scripts/Makefile.build:243: 
> drivers/hwtracing/coresight/coresight-tpdm.o] Error 1
> make[3]: *** [scripts/Makefile.build:480: drivers/hwtracing/coresight] 
> Error 2
> make[2]: *** [scripts/Makefile.build:480: drivers] Error 2
> make[1]: *** [/ssd/src/LINUX-CORESIGHT/Makefile:2032: .] Error 2
> make: *** [Makefile:234: __sub-make] Error 2
>
I will update this in the next patch series.


Best,

Tao

> Suzuki