[PATCH v4 4/7] coresight-tgu: Add TGU decode support

[Songwei Chai <quic_songchai@quicinc.com>]

Decoding is when all the potential pieces for creating a trigger
are brought together for a given step. Example - there may be a
counter keeping track of some occurrences and a priority-group that
is being used to detect a pattern on the sense inputs. These 2
inputs to condition_decode must be programmed, for a given step,
to establish the condition for the trigger, or movement to another
steps.

Signed-off-by: Songwei Chai <quic_songchai@quicinc.com>
---
 .../ABI/testing/sysfs-bus-coresight-devices-tgu    |   7 +
 drivers/hwtracing/coresight/coresight-tgu.c        | 186 ++++++++++++++++++---
 drivers/hwtracing/coresight/coresight-tgu.h        |  29 +++-
 3 files changed, 196 insertions(+), 26 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tgu b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tgu
index 58434097688388ab5d755030c52acca75f04cfb6..50967ca039d88d7aa16e3d9c92aec32fef2b3498 100644
--- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tgu
+++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tgu
@@ -14,3 +14,10 @@ KernelVersion   6.15
 Contact:        Jinlong Mao (QUIC) <quic_jinlmao@quicinc.com>, Sam Chai (QUIC) <quic_songchai@quicinc.com>
 Description:
                 (RW) Set/Get the sensed signal with specific step and priority for TGU.
+
+What:           /sys/bus/coresight/devices/<tgu-name>/step[0:7]_condition_decode/reg[0:3]
+Date:           February 2025
+KernelVersion   6.15
+Contact:        Jinlong Mao (QUIC) <quic_jinlmao@quicinc.com>, Sam Chai (QUIC) <quic_songchai@quicinc.com>
+Description:
+                (RW) Set/Get the decode mode with specific step for TGU.
\ No newline at end of file
diff --git a/drivers/hwtracing/coresight/coresight-tgu.c b/drivers/hwtracing/coresight/coresight-tgu.c
index 6dbfd4c604b1fe6335e0cdff69521a08325c1f4d..8dbe8ab30174d97d754dcac23e2666c2cbfe4a48 100644
--- a/drivers/hwtracing/coresight/coresight-tgu.c
+++ b/drivers/hwtracing/coresight/coresight-tgu.c
@@ -21,13 +21,35 @@ static int calculate_array_location(struct tgu_drvdata *drvdata,
 				    int step_index, int operation_index,
 				    int reg_index)
 {
-	int ret;
+	int ret = -EINVAL;
+
+	switch (operation_index) {
+	case TGU_PRIORITY0:
+	case TGU_PRIORITY1:
+	case TGU_PRIORITY2:
+	case TGU_PRIORITY3:
+		ret = operation_index * (drvdata->max_step) *
+			      (drvdata->max_reg) +
+		      step_index * (drvdata->max_reg) + reg_index;
+		break;
+	case TGU_CONDITION_DECODE:
+		ret = step_index * (drvdata->max_condition_decode) +
+		      reg_index;
+		break;
+	default:
+		break;
+	}
+	return ret;
+}
 
-	ret = operation_index * (drvdata->max_step) *
-		      (drvdata->max_reg) +
-	      step_index * (drvdata->max_reg) + reg_index;
+static int check_array_location(struct tgu_drvdata *drvdata, int step,
+				int ops, int reg)
+{
+	int result = calculate_array_location(drvdata, step, ops, reg);
 
-	return ret;
+	if (result == -EINVAL)
+		dev_err(&drvdata->csdev->dev, "%s - Fail\n", __func__);
+	return result;
 }
 
 static ssize_t tgu_dataset_show(struct device *dev,
@@ -36,13 +58,33 @@ static ssize_t tgu_dataset_show(struct device *dev,
 	struct tgu_drvdata *drvdata = dev_get_drvdata(dev->parent);
 	struct tgu_attribute *tgu_attr =
 		container_of(attr, struct tgu_attribute, attr);
+	int ret = 0;
+
+	ret = check_array_location(drvdata, tgu_attr->step_index,
+				tgu_attr->operation_index, tgu_attr->reg_num);
+	if (ret == -EINVAL)
+		return ret;
 
-	return sysfs_emit(buf, "0x%x\n",
-			  drvdata->value_table->priority[
-					calculate_array_location(
-					drvdata, tgu_attr->step_index,
-					tgu_attr->operation_index,
-					tgu_attr->reg_num)]);
+	switch (tgu_attr->operation_index) {
+	case TGU_PRIORITY0:
+	case TGU_PRIORITY1:
+	case TGU_PRIORITY2:
+	case TGU_PRIORITY3:
+		return sysfs_emit(buf, "0x%x\n",
+				  drvdata->value_table->priority[calculate_array_location(
+					  drvdata, tgu_attr->step_index,
+					  tgu_attr->operation_index,
+					  tgu_attr->reg_num)]);
+	case TGU_CONDITION_DECODE:
+		return sysfs_emit(buf, "0x%x\n",
+				  drvdata->value_table->condition_decode[calculate_array_location(
+					  drvdata, tgu_attr->step_index,
+					  tgu_attr->operation_index,
+					  tgu_attr->reg_num)]);
+	default:
+		break;
+	}
+	return -EINVAL;
 }
 
 static ssize_t tgu_dataset_store(struct device *dev,
@@ -51,20 +93,44 @@ static ssize_t tgu_dataset_store(struct device *dev,
 				 size_t size)
 {
 	unsigned long val;
+	int ret = -EINVAL;
 
 	struct tgu_drvdata *tgu_drvdata = dev_get_drvdata(dev->parent);
 	struct tgu_attribute *tgu_attr =
 		container_of(attr, struct tgu_attribute, attr);
 
 	if (kstrtoul(buf, 0, &val))
-		return -EINVAL;
+		return ret;
 
-	guard(spinlock)(&tgu_drvdata->spinlock);
-	tgu_drvdata->value_table->priority[calculate_array_location(
-		tgu_drvdata, tgu_attr->step_index, tgu_attr->operation_index,
-		tgu_attr->reg_num)] = val;
+	ret = check_array_location(tgu_drvdata, tgu_attr->step_index,
+		tgu_attr->operation_index, tgu_attr->reg_num);
 
-	return size;
+	if (ret == -EINVAL)
+		return ret;
+
+	guard(spinlock)(&tgu_drvdata->spinlock);
+	switch (tgu_attr->operation_index) {
+	case TGU_PRIORITY0:
+	case TGU_PRIORITY1:
+	case TGU_PRIORITY2:
+	case TGU_PRIORITY3:
+		tgu_drvdata->value_table->priority[calculate_array_location(
+			tgu_drvdata, tgu_attr->step_index,
+			tgu_attr->operation_index,
+			tgu_attr->reg_num)] = val;
+		ret = size;
+		break;
+	case TGU_CONDITION_DECODE:
+		tgu_drvdata->value_table->condition_decode[calculate_array_location(
+			tgu_drvdata, tgu_attr->step_index,
+			tgu_attr->operation_index,
+			tgu_attr->reg_num)] = val;
+		ret = size;
+		break;
+	default:
+		break;
+	}
+	return ret;
 }
 
 static umode_t tgu_node_visible(struct kobject *kobject,
@@ -81,34 +147,70 @@ static umode_t tgu_node_visible(struct kobject *kobject,
 		container_of(dev_attr, struct tgu_attribute, attr);
 
 	if (tgu_attr->step_index < drvdata->max_step) {
-		ret = (tgu_attr->reg_num < drvdata->max_reg) ?
-			      attr->mode :
-			      0;
+		switch (tgu_attr->operation_index) {
+		case TGU_PRIORITY0:
+		case TGU_PRIORITY1:
+		case TGU_PRIORITY2:
+		case TGU_PRIORITY3:
+			ret = (tgu_attr->reg_num < drvdata->max_reg) ?
+				      attr->mode :
+				      0;
+			break;
+		case TGU_CONDITION_DECODE:
+			ret = (tgu_attr->reg_num <
+			       drvdata->max_condition_decode) ?
+				      attr->mode :
+				      0;
+			break;
+		default:
+			break;
+		}
 	}
 	return ret;
 }
 
-static void tgu_write_all_hw_regs(struct tgu_drvdata *drvdata)
+static ssize_t tgu_write_all_hw_regs(struct tgu_drvdata *drvdata)
 {
-	int i, j, k;
+	int i, j, k, ret;
 
 	CS_UNLOCK(drvdata->base);
 
 	for (i = 0; i < drvdata->max_step; i++) {
 		for (j = 0; j < MAX_PRIORITY; j++) {
 			for (k = 0; k < drvdata->max_reg; k++) {
+
+				ret = check_array_location(drvdata, i, j, k);
+				if (ret == -EINVAL)
+					goto exit;
+
 				tgu_writel(drvdata,
 					   drvdata->value_table->priority
 						   [calculate_array_location(
-							drvdata, i, j, k)],
+							   drvdata, i, j, k)],
 					   PRIORITY_REG_STEP(i, j, k));
 			}
 		}
 	}
 
+	for (i = 0; i < drvdata->max_step; i++) {
+		for (j = 0; j < drvdata->max_condition_decode; j++) {
+			ret = check_array_location(drvdata, i, TGU_CONDITION_DECODE, j);
+			if (ret == -EINVAL)
+				goto exit;
+
+			tgu_writel(drvdata,
+				   drvdata->value_table->condition_decode
+					   [calculate_array_location(
+						   drvdata, i,
+						   TGU_CONDITION_DECODE, j)],
+				   CONDITION_DECODE_STEP(i, j));
+		}
+	}
 	/* Enable TGU to program the triggers */
 	tgu_writel(drvdata, 1, TGU_CONTROL);
+exit:
 	CS_LOCK(drvdata->base);
+	return ret >= 0 ? 0 : ret;
 }
 
 static void tgu_set_reg_number(struct tgu_drvdata *drvdata)
@@ -139,9 +241,21 @@ static void tgu_set_steps(struct tgu_drvdata *drvdata)
 	drvdata->max_step = num_steps;
 }
 
+static void tgu_set_conditions(struct tgu_drvdata *drvdata)
+{
+	int num_conditions;
+	u32 devid;
+
+	devid = readl_relaxed(drvdata->base + CORESIGHT_DEVID);
+
+	num_conditions = TGU_DEVID_CONDITIONS(devid);
+	drvdata->max_condition_decode = num_conditions;
+}
+
 static int tgu_enable(struct coresight_device *csdev, enum cs_mode mode,
 		      void *data)
 {
+	int ret = 0;
 	struct tgu_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
 	spin_lock(&drvdata->spinlock);
@@ -150,11 +264,15 @@ static int tgu_enable(struct coresight_device *csdev, enum cs_mode mode,
 		spin_unlock(&drvdata->spinlock);
 		return -EBUSY;
 	}
-	tgu_write_all_hw_regs(drvdata);
+	ret = tgu_write_all_hw_regs(drvdata);
+
+	if (ret == -EINVAL)
+		goto exit;
 	drvdata->enable = true;
 
+exit:
 	spin_unlock(&drvdata->spinlock);
-	return 0;
+	return ret;
 }
 
 static int tgu_disable(struct coresight_device *csdev, void *data)
@@ -271,6 +389,14 @@ static const struct attribute_group *tgu_attr_groups[] = {
 	PRIORITY_ATTRIBUTE_GROUP_INIT(7, 1),
 	PRIORITY_ATTRIBUTE_GROUP_INIT(7, 2),
 	PRIORITY_ATTRIBUTE_GROUP_INIT(7, 3),
+	CONDITION_DECODE_ATTRIBUTE_GROUP_INIT(0),
+	CONDITION_DECODE_ATTRIBUTE_GROUP_INIT(1),
+	CONDITION_DECODE_ATTRIBUTE_GROUP_INIT(2),
+	CONDITION_DECODE_ATTRIBUTE_GROUP_INIT(3),
+	CONDITION_DECODE_ATTRIBUTE_GROUP_INIT(4),
+	CONDITION_DECODE_ATTRIBUTE_GROUP_INIT(5),
+	CONDITION_DECODE_ATTRIBUTE_GROUP_INIT(6),
+	CONDITION_DECODE_ATTRIBUTE_GROUP_INIT(7),
 	NULL,
 };
 
@@ -307,6 +433,7 @@ static int tgu_probe(struct amba_device *adev, const struct amba_id *id)
 
 	tgu_set_reg_number(drvdata);
 	tgu_set_steps(drvdata);
+	tgu_set_conditions(drvdata);
 
 	drvdata->value_table =
 		devm_kzalloc(dev, sizeof(*drvdata->value_table), GFP_KERNEL);
@@ -322,6 +449,15 @@ static int tgu_probe(struct amba_device *adev, const struct amba_id *id)
 	if (!drvdata->value_table->priority)
 		return -ENOMEM;
 
+	drvdata->value_table->condition_decode = devm_kzalloc(
+		dev,
+		drvdata->max_condition_decode * drvdata->max_step *
+			sizeof(*(drvdata->value_table->condition_decode)),
+		GFP_KERNEL);
+
+	if (!drvdata->value_table->condition_decode)
+		return -ENOMEM;
+
 	drvdata->enable = false;
 	desc.type = CORESIGHT_DEV_TYPE_HELPER;
 	desc.pdata = adev->dev.platform_data;
diff --git a/drivers/hwtracing/coresight/coresight-tgu.h b/drivers/hwtracing/coresight/coresight-tgu.h
index f07ead50536581578bcae7248d913207db6ac8ea..691da393ffa30fe7501ba0e8c4a058d8d561fc14 100644
--- a/drivers/hwtracing/coresight/coresight-tgu.h
+++ b/drivers/hwtracing/coresight/coresight-tgu.h
@@ -15,6 +15,7 @@
 
 #define TGU_DEVID_SENSE_INPUT(devid_val) ((int) BMVAL(devid_val, 10, 17))
 #define TGU_DEVID_STEPS(devid_val) ((int)BMVAL(devid_val, 3, 6))
+#define TGU_DEVID_CONDITIONS(devid_val) ((int)BMVAL(devid_val, 0, 2))
 #define NUMBER_BITS_EACH_SIGNAL 4
 #define LENGTH_REGISTER 32
 
@@ -48,6 +49,7 @@
  */
 #define STEP_OFFSET 0x1D8
 #define PRIORITY_START_OFFSET 0x0074
+#define CONDITION_DECODE_OFFSET 0x0050
 #define PRIORITY_OFFSET 0x60
 #define REG_OFFSET 0x4
 
@@ -56,6 +58,9 @@
 	(PRIORITY_START_OFFSET + PRIORITY_OFFSET * priority +\
 	REG_OFFSET * reg + STEP_OFFSET * step)
 
+#define CONDITION_DECODE_STEP(step, decode) \
+	(CONDITION_DECODE_OFFSET + REG_OFFSET * decode + STEP_OFFSET * step)
+
 #define tgu_dataset_rw(name, step_index, type, reg_num)                  \
 	(&((struct tgu_attribute[]){ {                                   \
 		__ATTR(name, 0644, tgu_dataset_show, tgu_dataset_store), \
@@ -68,6 +73,9 @@
 	tgu_dataset_rw(reg##reg_num, step_index, TGU_PRIORITY##priority, \
 		       reg_num)
 
+#define STEP_DECODE(step_index, reg_num) \
+	tgu_dataset_rw(reg##reg_num, step_index, TGU_CONDITION_DECODE, reg_num)
+
 #define STEP_PRIORITY_LIST(step_index, priority)  \
 	{STEP_PRIORITY(step_index, 0, priority),  \
 	 STEP_PRIORITY(step_index, 1, priority),  \
@@ -90,6 +98,14 @@
 	 NULL			\
 	}
 
+#define STEP_DECODE_LIST(n) \
+	{STEP_DECODE(n, 0), \
+	 STEP_DECODE(n, 1), \
+	 STEP_DECODE(n, 2), \
+	 STEP_DECODE(n, 3), \
+	 NULL           \
+	}
+
 #define PRIORITY_ATTRIBUTE_GROUP_INIT(step, priority)\
 	(&(const struct attribute_group){\
 		.attrs = (struct attribute*[])STEP_PRIORITY_LIST(step, priority),\
@@ -97,11 +113,19 @@
 		.name = "step" #step "_priority" #priority \
 	})
 
+#define CONDITION_DECODE_ATTRIBUTE_GROUP_INIT(step)\
+	(&(const struct attribute_group){\
+		.attrs = (struct attribute*[])STEP_DECODE_LIST(step),\
+		.is_visible = tgu_node_visible,\
+		.name = "step" #step "_condition_decode" \
+	})
+
 enum operation_index {
 	TGU_PRIORITY0,
 	TGU_PRIORITY1,
 	TGU_PRIORITY2,
-	TGU_PRIORITY3
+	TGU_PRIORITY3,
+	TGU_CONDITION_DECODE
 
 };
 
@@ -117,6 +141,7 @@ struct tgu_attribute {
 
 struct value_table {
 	unsigned int *priority;
+	unsigned int *condition_decode;
 };
 
 /**
@@ -129,6 +154,7 @@ struct value_table {
  * @value_table: Store given value based on relevant parameters.
  * @max_reg: Maximum number of registers
  * @max_step: Maximum step size
+ * @max_condition_decode: Maximum number of condition_decode
  *
  * This structure defines the data associated with a TGU device,
  * including its base address, device pointers, clock, spinlock for
@@ -144,6 +170,7 @@ struct tgu_drvdata {
 	struct value_table *value_table;
 	int max_reg;
 	int max_step;
+	int max_condition_decode;
 };
 
 #endif

-- 
2.34.1