coresight-tpdm: Add nodes for dsb msr support

Add the nodes for DSB subunit MSR(mux select register) support.
The TPDM MSR (mux select register) interface is an optional
interface and associated bank of registers per TPDM subunit.
The intent of mux select registers is to control muxing structures
driving the TPDM’s’ various subunit interfaces.

Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/1695882586-10306-14-git-send-email-quic_taozha@quicinc.com

Author: Tao Zhang

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

@@ -162,3 +162,11 @@ Description:
 		Accepts only one of the 2 values -  0 or 1.
 		0 : Set the DSB pattern type to value.
 		1 : Set the DSB pattern type to toggle.
+
+What:		/sys/bus/coresight/devices/<tpdm-name>/dsb_msr/msr[0:31]
+Date:		March 2023
+KernelVersion	6.7
+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 DSB subunit
+		TPDM.

drivers/hwtracing/coresight/coresight-tpdm.c

@@ -61,6 +61,11 @@ static ssize_t tpdm_simple_dataset_show(struct device *dev,
 			return -EINVAL;
 		return sysfs_emit(buf, "0x%x\n",
 			drvdata->dsb->patt_mask[tpdm_attr->idx]);
+	case DSB_MSR:
+		if (tpdm_attr->idx >= drvdata->dsb_msr_num)
+			return -EINVAL;
+		return sysfs_emit(buf, "0x%x\n",
+				drvdata->dsb->msr[tpdm_attr->idx]);
 	}
 	return -EINVAL;
 }
@@ -107,6 +112,12 @@ static ssize_t tpdm_simple_dataset_store(struct device *dev,
 		else
 			ret = -EINVAL;
 		break;
+	case DSB_MSR:
+		if (tpdm_attr->idx < drvdata->dsb_msr_num)
+			drvdata->dsb->msr[tpdm_attr->idx] = val;
+		else
+			ret = -EINVAL;
+		break;
 	default:
 		ret = -EINVAL;
 	}
@@ -132,6 +143,22 @@ static umode_t tpdm_dsb_is_visible(struct kobject *kobj,
 	return 0;
 }
 
+static umode_t tpdm_dsb_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->dsb_msr_num)
+		return attr->mode;
+
+	return 0;
+}
+
 static void tpdm_reset_datasets(struct tpdm_drvdata *drvdata)
 {
 	if (tpdm_has_dsb_dataset(drvdata)) {
@@ -193,6 +220,15 @@ static void set_dsb_tier(struct tpdm_drvdata *drvdata)
 	writel_relaxed(val, drvdata->base + TPDM_DSB_TIER);
 }
 
+static void set_dsb_msr(struct tpdm_drvdata *drvdata)
+{
+	int i;
+
+	for (i = 0; i < drvdata->dsb_msr_num; i++)
+		writel_relaxed(drvdata->dsb->msr[i],
+			   drvdata->base + TPDM_DSB_MSR(i));
+}
+
 static void tpdm_enable_dsb(struct tpdm_drvdata *drvdata)
 {
 	u32 val, i;
@@ -216,6 +252,8 @@ static void tpdm_enable_dsb(struct tpdm_drvdata *drvdata)
 
 	set_dsb_tier(drvdata);
 
+	set_dsb_msr(drvdata);
+
 	val = readl_relaxed(drvdata->base + TPDM_DSB_CR);
 	/* Set the mode of DSB dataset */
 	set_dsb_mode(drvdata, &val);
@@ -739,6 +777,42 @@ static struct attribute *tpdm_dsb_patt_attrs[] = {
 	NULL,
 };
 
+static struct attribute *tpdm_dsb_msr_attrs[] = {
+	DSB_MSR_ATTR(0),
+	DSB_MSR_ATTR(1),
+	DSB_MSR_ATTR(2),
+	DSB_MSR_ATTR(3),
+	DSB_MSR_ATTR(4),
+	DSB_MSR_ATTR(5),
+	DSB_MSR_ATTR(6),
+	DSB_MSR_ATTR(7),
+	DSB_MSR_ATTR(8),
+	DSB_MSR_ATTR(9),
+	DSB_MSR_ATTR(10),
+	DSB_MSR_ATTR(11),
+	DSB_MSR_ATTR(12),
+	DSB_MSR_ATTR(13),
+	DSB_MSR_ATTR(14),
+	DSB_MSR_ATTR(15),
+	DSB_MSR_ATTR(16),
+	DSB_MSR_ATTR(17),
+	DSB_MSR_ATTR(18),
+	DSB_MSR_ATTR(19),
+	DSB_MSR_ATTR(20),
+	DSB_MSR_ATTR(21),
+	DSB_MSR_ATTR(22),
+	DSB_MSR_ATTR(23),
+	DSB_MSR_ATTR(24),
+	DSB_MSR_ATTR(25),
+	DSB_MSR_ATTR(26),
+	DSB_MSR_ATTR(27),
+	DSB_MSR_ATTR(28),
+	DSB_MSR_ATTR(29),
+	DSB_MSR_ATTR(30),
+	DSB_MSR_ATTR(31),
+	NULL,
+};
+
 static struct attribute *tpdm_dsb_attrs[] = {
 	&dev_attr_dsb_mode.attr,
 	&dev_attr_dsb_trig_ts.attr,
@@ -769,12 +843,19 @@ static struct attribute_group tpdm_dsb_patt_grp = {
 	.name = "dsb_patt",
 };
 
+static struct attribute_group tpdm_dsb_msr_grp = {
+	.attrs = tpdm_dsb_msr_attrs,
+	.is_visible = tpdm_dsb_msr_is_visible,
+	.name = "dsb_msr",
+};
+
 static const struct attribute_group *tpdm_attr_grps[] = {
 	&tpdm_attr_grp,
 	&tpdm_dsb_attr_grp,
 	&tpdm_dsb_edge_grp,
 	&tpdm_dsb_trig_patt_grp,
 	&tpdm_dsb_patt_grp,
+	&tpdm_dsb_msr_grp,
 	NULL,
 };
 
@@ -809,6 +890,10 @@ static int tpdm_probe(struct amba_device *adev, const struct amba_id *id)
 	if (ret)
 		return ret;
 
+	if (drvdata && tpdm_has_dsb_dataset(drvdata))
+		of_property_read_u32(drvdata->dev->of_node,
+			   "qcom,dsb_msr_num", &drvdata->dsb_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

@@ -18,6 +18,7 @@
 #define TPDM_DSB_XPMR(n)	(0x7E8 + (n * 4))
 #define TPDM_DSB_EDCR(n)	(0x808 + (n * 4))
 #define TPDM_DSB_EDCMR(n)	(0x848 + (n * 4))
+#define TPDM_DSB_MSR(n)		(0x980 + (n * 4))
 
 /* Enable bit for DSB subunit */
 #define TPDM_DSB_CR_ENA		BIT(0)
@@ -90,6 +91,8 @@
 #define TPDM_DSB_MAX_EDCMR	8
 /* MAX number of DSB pattern */
 #define TPDM_DSB_MAX_PATT	8
+/* MAX number of DSB MSR */
+#define TPDM_DSB_MAX_MSR 32
 
 #define tpdm_simple_dataset_ro(name, mem, idx)			\
 	(&((struct tpdm_dataset_attribute[]) {			\
@@ -134,6 +137,10 @@
 		tpdm_simple_dataset_rw(tpmr##nr,		\
 		DSB_PATT_MASK, nr)
 
+#define DSB_MSR_ATTR(nr)					\
+		tpdm_simple_dataset_rw(msr##nr,			\
+		DSB_MSR, nr)
+
 /**
  * struct dsb_dataset - specifics associated to dsb dataset
  * @mode:             DSB programming mode
@@ -144,6 +151,7 @@
  * @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:          Enable/Disable pattern timestamp
  * @patt_type:        Set pattern type
  * @trig_ts:          Enable/Disable trigger timestamp.
@@ -158,6 +166,7 @@ struct dsb_dataset {
 	u32			patt_mask[TPDM_DSB_MAX_PATT];
 	u32			trig_patt[TPDM_DSB_MAX_PATT];
 	u32			trig_patt_mask[TPDM_DSB_MAX_PATT];
+	u32			msr[TPDM_DSB_MAX_MSR];
 	bool			patt_ts;
 	bool			patt_type;
 	bool			trig_ts;
@@ -173,6 +182,7 @@ struct dsb_dataset {
  * @enable:     enable status of the component.
  * @datasets:   The datasets types present of the TPDM.
  * @dsb         Specifics associated to TPDM DSB.
+ * @dsb_msr_num Number of MSR supported by DSB TPDM
  */
 
 struct tpdm_drvdata {
@@ -183,6 +193,7 @@ struct tpdm_drvdata {
 	bool			enable;
 	unsigned long		datasets;
 	struct dsb_dataset	*dsb;
+	u32			dsb_msr_num;
 };
 
 /* Enumerate members of various datasets */
@@ -193,6 +204,7 @@ enum dataset_mem {
 	DSB_TRIG_PATT_MASK,
 	DSB_PATT,
 	DSB_PATT_MASK,
+	DSB_MSR,
 };
 
 /**