coresight-tpdm: Add msr register support for CMB

Add the nodes for CMB subunit MSR(mux select register) support.
CMB MSRs(mux select registers) is to separate mux, arbitration,
interleaving,data packing control from stream filtering control.
Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
Signed-off-by: Mao Jinlong <quic_jinlmao@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/1707024641-22460-11-git-send-email-quic_taozha@quicinc.com

Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm

@@ -249,3 +249,11 @@ Description:
 		Accepts only one of the 2 values -  0 or 1.
 		0 : Disable the timestamp of all trace packets.
 		1 : Enable the timestamp of all trace packets.
+
+What:		/sys/bus/coresight/devices/<tpdm-name>/cmb_msr/msr[0:31]
+Date:		January 2024
+KernelVersion	6.9
+Contact:	Jinlong Mao (QUIC) <quic_jinlmao@quicinc.com>, Tao Zhang (QUIC) <quic_taozha@quicinc.com>
+Description:
+		(RW) Set/Get the MSR(mux select register) for the CMB subunit
+		TPDM.

drivers/hwtracing/coresight/coresight-tpdm.c

@@ -86,6 +86,11 @@ static ssize_t tpdm_simple_dataset_show(struct device *dev,
 			return -EINVAL;
 		return sysfs_emit(buf, "0x%x\n",
 			drvdata->cmb->patt_mask[tpdm_attr->idx]);
+	case CMB_MSR:
+		if (tpdm_attr->idx >= drvdata->cmb_msr_num)
+			return -EINVAL;
+		return sysfs_emit(buf, "0x%x\n",
+				drvdata->cmb->msr[tpdm_attr->idx]);
 	}
 	return -EINVAL;
 }
@@ -162,6 +167,12 @@ static ssize_t tpdm_simple_dataset_store(struct device *dev,
 			ret = size;
 		}
 		break;
+	case CMB_MSR:
+		if (tpdm_attr->idx < drvdata->cmb_msr_num) {
+			drvdata->cmb->msr[tpdm_attr->idx] = val;
+			ret = size;
+		}
+		break;
 	default:
 		break;
 	}
@@ -209,6 +220,23 @@ static umode_t tpdm_dsb_msr_is_visible(struct kobject *kobj,
 	return 0;
 }
 
+static umode_t tpdm_cmb_msr_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);
+
+	struct device_attribute *dev_attr =
+		container_of(attr, struct device_attribute, attr);
+	struct tpdm_dataset_attribute *tpdm_attr =
+		container_of(dev_attr, struct tpdm_dataset_attribute, attr);
+
+	if (tpdm_attr->idx < drvdata->cmb_msr_num)
+		return attr->mode;
+
+	return 0;
+}
+
 static void tpdm_reset_datasets(struct tpdm_drvdata *drvdata)
 {
 	if (tpdm_has_dsb_dataset(drvdata)) {
@@ -347,6 +375,15 @@ static void set_cmb_tier(struct tpdm_drvdata *drvdata)
 	writel_relaxed(val, drvdata->base + TPDM_CMB_TIER);
 }
 
+static void set_cmb_msr(struct tpdm_drvdata *drvdata)
+{
+	int i;
+
+	for (i = 0; i < drvdata->cmb_msr_num; i++)
+		writel_relaxed(drvdata->cmb->msr[i],
+			   drvdata->base + TPDM_CMB_MSR(i));
+}
+
 static void tpdm_enable_cmb(struct tpdm_drvdata *drvdata)
 {
 	u32 val, i;
@@ -367,6 +404,7 @@ static void tpdm_enable_cmb(struct tpdm_drvdata *drvdata)
 	}
 
 	set_cmb_tier(drvdata);
+	set_cmb_msr(drvdata);
 
 	val = readl_relaxed(drvdata->base + TPDM_CMB_CR);
 	/*
@@ -1072,6 +1110,42 @@ static struct attribute *tpdm_cmb_patt_attrs[] = {
 	NULL,
 };
 
+static struct attribute *tpdm_cmb_msr_attrs[] = {
+	CMB_MSR_ATTR(0),
+	CMB_MSR_ATTR(1),
+	CMB_MSR_ATTR(2),
+	CMB_MSR_ATTR(3),
+	CMB_MSR_ATTR(4),
+	CMB_MSR_ATTR(5),
+	CMB_MSR_ATTR(6),
+	CMB_MSR_ATTR(7),
+	CMB_MSR_ATTR(8),
+	CMB_MSR_ATTR(9),
+	CMB_MSR_ATTR(10),
+	CMB_MSR_ATTR(11),
+	CMB_MSR_ATTR(12),
+	CMB_MSR_ATTR(13),
+	CMB_MSR_ATTR(14),
+	CMB_MSR_ATTR(15),
+	CMB_MSR_ATTR(16),
+	CMB_MSR_ATTR(17),
+	CMB_MSR_ATTR(18),
+	CMB_MSR_ATTR(19),
+	CMB_MSR_ATTR(20),
+	CMB_MSR_ATTR(21),
+	CMB_MSR_ATTR(22),
+	CMB_MSR_ATTR(23),
+	CMB_MSR_ATTR(24),
+	CMB_MSR_ATTR(25),
+	CMB_MSR_ATTR(26),
+	CMB_MSR_ATTR(27),
+	CMB_MSR_ATTR(28),
+	CMB_MSR_ATTR(29),
+	CMB_MSR_ATTR(30),
+	CMB_MSR_ATTR(31),
+	NULL,
+};
+
 static struct attribute *tpdm_dsb_attrs[] = {
 	&dev_attr_dsb_mode.attr,
 	&dev_attr_dsb_trig_ts.attr,
@@ -1132,6 +1206,12 @@ static struct attribute_group tpdm_cmb_patt_grp = {
 	.name = "cmb_patt",
 };
 
+static struct attribute_group tpdm_cmb_msr_grp = {
+	.attrs = tpdm_cmb_msr_attrs,
+	.is_visible = tpdm_cmb_msr_is_visible,
+	.name = "cmb_msr",
+};
+
 static const struct attribute_group *tpdm_attr_grps[] = {
 	&tpdm_attr_grp,
 	&tpdm_dsb_attr_grp,
@@ -1142,6 +1222,7 @@ static const struct attribute_group *tpdm_attr_grps[] = {
 	&tpdm_cmb_attr_grp,
 	&tpdm_cmb_trig_patt_grp,
 	&tpdm_cmb_patt_grp,
+	&tpdm_cmb_msr_grp,
 	NULL,
 };
 
@@ -1180,6 +1261,10 @@ static int tpdm_probe(struct amba_device *adev, const struct amba_id *id)
 		of_property_read_u32(drvdata->dev->of_node,
 			   "qcom,dsb-msrs-num", &drvdata->dsb_msr_num);
 
+	if (drvdata && tpdm_has_cmb_dataset(drvdata))
+		of_property_read_u32(drvdata->dev->of_node,
+			   "qcom,cmb-msrs-num", &drvdata->cmb_msr_num);
+
 	/* Set up coresight component description */
 	desc.name = coresight_alloc_device_name(&tpdm_devs, dev);
 	if (!desc.name)

drivers/hwtracing/coresight/coresight-tpdm.h

@@ -21,6 +21,8 @@
 #define TPDM_CMB_XPR(n)		(0xA18 + (n * 4))
 /* CMB subunit trigger pattern mask registers */
 #define TPDM_CMB_XPMR(n)	(0xA20 + (n * 4))
+/* CMB MSR register */
+#define TPDM_CMB_MSR(n)		(0xA80 + (n * 4))
 
 /* Enable bit for CMB subunit */
 #define TPDM_CMB_CR_ENA		BIT(0)
@@ -36,6 +38,9 @@
 /* Patten register number */
 #define TPDM_CMB_MAX_PATT		2
 
+/* MAX number of DSB MSR */
+#define TPDM_CMB_MAX_MSR 32
+
 /* DSB Subunit Registers */
 #define TPDM_DSB_CR		(0x780)
 #define TPDM_DSB_TIER		(0x784)
@@ -203,6 +208,10 @@
 		tpdm_patt_enable_ts(enable_ts,			\
 		CMB_PATT)
 
+#define CMB_MSR_ATTR(nr)					\
+		tpdm_simple_dataset_rw(msr##nr,			\
+		CMB_MSR, nr)
+
 /**
  * struct dsb_dataset - specifics associated to dsb dataset
  * @mode:             DSB programming mode
@@ -242,6 +251,7 @@ struct dsb_dataset {
  * @patt_mask:        Save value for pattern mask
  * @trig_patt:        Save value for trigger pattern
  * @trig_patt_mask:   Save value for trigger pattern mask
+ * @msr               Save value for MSR
  * @patt_ts:          Indicates if pattern match for timestamp is enabled.
  * @trig_ts:          Indicates if CTI trigger for timestamp is enabled.
  * @ts_all:           Indicates if timestamp is enabled for all packets.
@@ -252,6 +262,7 @@ struct cmb_dataset {
 	u32			patt_mask[TPDM_CMB_MAX_PATT];
 	u32			trig_patt[TPDM_CMB_MAX_PATT];
 	u32			trig_patt_mask[TPDM_CMB_MAX_PATT];
+	u32			msr[TPDM_CMB_MAX_MSR];
 	bool			patt_ts;
 	bool			trig_ts;
 	bool			ts_all;
@@ -268,6 +279,7 @@ struct cmb_dataset {
  * @dsb         Specifics associated to TPDM DSB.
  * @cmb         Specifics associated to TPDM CMB.
  * @dsb_msr_num Number of MSR supported by DSB TPDM
+ * @cmb_msr_num Number of MSR supported by CMB TPDM
  */
 
 struct tpdm_drvdata {
@@ -280,6 +292,7 @@ struct tpdm_drvdata {
 	struct dsb_dataset	*dsb;
 	struct cmb_dataset	*cmb;
 	u32			dsb_msr_num;
+	u32			cmb_msr_num;
 };
 
 /* Enumerate members of various datasets */
@@ -294,7 +307,8 @@ enum dataset_mem {
 	CMB_TRIG_PATT,
 	CMB_TRIG_PATT_MASK,
 	CMB_PATT,
-	CMB_PATT_MASK
+	CMB_PATT_MASK,
+	CMB_MSR
 };
 
 /**