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

From: Tao Zhang
Date: Mon Jun 03 2024 - 22:49:22 EST


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.

Signed-off-by: Tao Zhang <quic_taozha@xxxxxxxxxxx>
---
.../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 b4d0fc8d319d..3bae880cddb6 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@xxxxxxxxxxx>, 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@xxxxxxxxxxx>
+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 2989fa4787fe..fba4f8877e96 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)) {
@@ -1013,6 +1025,34 @@ 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,
@@ -1175,6 +1215,11 @@ 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,
@@ -1241,6 +1286,11 @@ 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,
@@ -1252,6 +1302,7 @@ 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 0c4e216790e3..887d4464b076 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)
--
2.17.1