Re: [PATCH v1 RESEND 2/3] coresight-tpdm: Add support to select lane

[Suzuki K Poulose <suzuki.poulose@arm.com>]

On 11/10/2024 07:47, Mao Jinlong wrote:
> From: Tao Zhang <quic_taozha@quicinc.com>
> 
> TPDM MCMB subunits supports up to 8 lanes CMB. For MCMB
> configurations, the field "XTRIG_LNSEL" in CMB_CR register selects
> which lane participates in the output pattern mach cross trigger
> mechanism goverened by the M_CMB_DXPR and M_CMB_XPMR regisers.

minor nit: s/goverened/governed/

> 
> Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
> ---
>   .../testing/sysfs-bus-coresight-devices-tpdm  |  8 +++
>   drivers/hwtracing/coresight/coresight-tpdm.c  | 51 +++++++++++++++++++
>   drivers/hwtracing/coresight/coresight-tpdm.h  |  3 ++
>   3 files changed, 62 insertions(+)
> 
> diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
> index bf710ea6e0ef..b3292fa2a022 100644
> --- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
> +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
> @@ -257,3 +257,11 @@ Contact:	Jinlong Mao (QUIC) <quic_jinlmao@quicinc.com>, Tao Zhang (QUIC) <quic_t
>   Description:
>   		(RW) Set/Get the MSR(mux select register) for the CMB subunit
>   		TPDM.
> +
> +What:		/sys/bus/coresight/devices/<tpdm-name>/mcmb_trig_lane
> +Date:		June 2024
> +KernelVersion	6.9
> +Contact:	Tao Zhang (QUIC) <quic_taozha@quicinc.com>

Didn't we already discuss about modifying the date and version ? Simply 
resending the patch is not going to help if it is not uptodate.

Please fix all the dates in the series

Suzuki

> +Description:
> +		(RW) Set/Get which lane participates in the output pattern
> +		match cross trigger mechanism for the MCMB subunit TPDM.
> diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c b/drivers/hwtracing/coresight/coresight-tpdm.c
> index 58f8c3e804c1..f32c119e1b67 100644
> --- a/drivers/hwtracing/coresight/coresight-tpdm.c
> +++ b/drivers/hwtracing/coresight/coresight-tpdm.c
> @@ -238,6 +238,18 @@ static umode_t tpdm_cmb_msr_is_visible(struct kobject *kobj,
>   	return 0;
>   }
>   
> +static umode_t tpdm_mcmb_is_visible(struct kobject *kobj,
> +				    struct attribute *attr, int n)
> +{
> +	struct device *dev = kobj_to_dev(kobj);
> +	struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
> +
> +	if (drvdata && tpdm_has_mcmb_dataset(drvdata))
> +		return attr->mode;
> +
> +	return 0;
> +}
> +
>   static void tpdm_reset_datasets(struct tpdm_drvdata *drvdata)
>   {
>   	if (tpdm_has_dsb_dataset(drvdata)) {
> @@ -1015,6 +1027,34 @@ static ssize_t cmb_trig_ts_store(struct device *dev,
>   }
>   static DEVICE_ATTR_RW(cmb_trig_ts);
>   
> +static ssize_t mcmb_trig_lane_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->cmb->mcmb->mcmb_trig_lane);
> +}
> +
> +static ssize_t mcmb_trig_lane_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_MCMB_MAX_LANES))
> +		return -EINVAL;
> +
> +	guard(spinlock)(&drvdata->spinlock);
> +	drvdata->cmb->mcmb->mcmb_trig_lane = val;
> +
> +	return size;
> +}
> +static DEVICE_ATTR_RW(mcmb_trig_lane);
> +
>   static struct attribute *tpdm_dsb_edge_attrs[] = {
>   	&dev_attr_ctrl_idx.attr,
>   	&dev_attr_ctrl_val.attr,
> @@ -1177,6 +1217,11 @@ static struct attribute *tpdm_cmb_msr_attrs[] = {
>   	NULL,
>   };
>   
> +static struct attribute *tpdm_mcmb_attrs[] = {
> +	&dev_attr_mcmb_trig_lane.attr,
> +	NULL,
> +};
> +
>   static struct attribute *tpdm_dsb_attrs[] = {
>   	&dev_attr_dsb_mode.attr,
>   	&dev_attr_dsb_trig_ts.attr,
> @@ -1243,6 +1288,11 @@ static struct attribute_group tpdm_cmb_msr_grp = {
>   	.name = "cmb_msr",
>   };
>   
> +static struct attribute_group tpdm_mcmb_attr_grp = {
> +	.attrs = tpdm_mcmb_attrs,
> +	.is_visible = tpdm_mcmb_is_visible,
> +};
> +
>   static const struct attribute_group *tpdm_attr_grps[] = {
>   	&tpdm_attr_grp,
>   	&tpdm_dsb_attr_grp,
> @@ -1254,6 +1304,7 @@ static const struct attribute_group *tpdm_attr_grps[] = {
>   	&tpdm_cmb_trig_patt_grp,
>   	&tpdm_cmb_patt_grp,
>   	&tpdm_cmb_msr_grp,
> +	&tpdm_mcmb_attr_grp,
>   	NULL,
>   };
>   
> diff --git a/drivers/hwtracing/coresight/coresight-tpdm.h b/drivers/hwtracing/coresight/coresight-tpdm.h
> index 2e84daad1a58..e72dc19da310 100644
> --- a/drivers/hwtracing/coresight/coresight-tpdm.h
> +++ b/drivers/hwtracing/coresight/coresight-tpdm.h
> @@ -45,6 +45,9 @@
>   /* MAX number of DSB MSR */
>   #define TPDM_CMB_MAX_MSR 32
>   
> +/* MAX lanes in the output pattern for MCMB configurations*/
> +#define TPDM_MCMB_MAX_LANES 8
> +
>   /* DSB Subunit Registers */
>   #define TPDM_DSB_CR		(0x780)
>   #define TPDM_DSB_TIER		(0x784)