[PATCH v6 2/2] coresight: cti: Add Qualcomm extended CTI support

Leo Yan leo.yan at arm.com
Thu Dec 4 00:38:02 PST 2025


On Wed, Dec 03, 2025 at 06:29:44PM +0000, Coresight ML wrote:

[...]

> > +/* Read registers with power check only (no enable check). */
> > +static ssize_t coresight_cti_reg_show(struct device *dev,
> > +				      struct device_attribute *attr, char *buf)
> > +{
> > +	struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
> > +	struct cs_off_attribute *cti_attr = container_of(attr, struct cs_off_attribute, attr);
> > +	u32 idx, val = 0;
> > +
> > +	pm_runtime_get_sync(dev->parent);
> > +	raw_spin_lock(&drvdata->spinlock);
> > +	idx = drvdata->config.ext_reg_sel;
> > +	if (drvdata->config.hw_powered) {
> > +		switch (cti_attr->off) {
> > +		case INDEX_CTITRIGINSTATUS:
> > +		case INDEX_CTITRIGOUTSTATUS:
> > +		case INDEX_ITTRIGINACK:
> > +		case INDEX_ITTRIGOUT:
> > +		case INDEX_ITTRIGOUTACK:
> > +		case INDEX_ITTRIGIN:

I read again and now I understand why you need "config.ext_reg_sel"
as an index for these expending registers.

I think you should extend attrs for the new adding registers:

  static struct attribute *coresight_cti_regs_attrs[] = {
      ...
      coresight_cti_reg(triginstatus, CTITRIGINSTATUS),
      /* Qcom CTI only for triginstatus1/2/3 */
      coresight_cti_reg(triginstatus1, CTITRIGINSTATUS + 0x4),
      coresight_cti_reg(triginstatus2, CTITRIGINSTATUS + 0x8),
      coresight_cti_reg(triginstatus3, CTITRIGINSTATUS + 0xc),
      ...
  }

Then, you can add a is_visible() in coresight_cti_regs_group:

  static umode_t coresight_cti_regs_is_visible(struct kobject *kobj,
                  struct attribute *attr, int n)
  {
          struct device *dev = container_of(kobj, struct device, kobj);
          struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);

          /* Mute QCOM CTI registers for standard CTI module */
          if (!drvdata->is_qcom_cti) {
              if (attr == &triginstatus1.attr ||
                  attr == &triginstatus2.attr ||
                  attr == &triginstatus3.attr)
                  return 0;
          }

          return attr->mode;
  }

  static const struct attribute_group coresight_cti_regs_group = {
          .attrs = coresight_cti_regs_attrs,
          .name = "regs",
          .is_visible = coresight_cti_regs_is_visible,
  };

Thanks,
Leo



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