[PATCH v11 4/7] qcom-tgu: Add TGU decode support

Songwei Chai songwei.chai at oss.qualcomm.com
Wed Feb 25 18:04:51 PST 2026


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 <songwei.chai at oss.qualcomm.com>
---
 .../ABI/testing/sysfs-bus-amba-devices-tgu    |   7 +
 drivers/hwtracing/qcom/tgu.c                  | 157 +++++++++++++++---
 drivers/hwtracing/qcom/tgu.h                  |  28 ++++
 3 files changed, 171 insertions(+), 21 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-bus-amba-devices-tgu b/Documentation/ABI/testing/sysfs-bus-amba-devices-tgu
index 23ba73c4db0e..a18f6e4c797d 100644
--- a/Documentation/ABI/testing/sysfs-bus-amba-devices-tgu
+++ b/Documentation/ABI/testing/sysfs-bus-amba-devices-tgu
@@ -14,3 +14,10 @@ KernelVersion	6.20
 Contact:	Jinlong Mao <jinlong.mao at oss.qualcomm.com>, Songwei Chai <songwei.chai at oss.qualcomm.com>
 Description:
 		(RW) Set/Get the sensed signal with specific step and priority for TGU.
+
+What:		/sys/bus/amba/devices/<tgu-name>/step[0:7]_condition_decode/reg[0:3]
+Date:		February 2026
+KernelVersion	6.20
+Contact:	Jinlong Mao <jinlong.mao at oss.qualcomm.com>, Songwei Chai <songwei.chai at oss.qualcomm.com>
+Description:
+		(RW) Set/Get the decode mode with specific step for TGU.
diff --git a/drivers/hwtracing/qcom/tgu.c b/drivers/hwtracing/qcom/tgu.c
index 14d6ad410d89..85fe1140eab5 100644
--- a/drivers/hwtracing/qcom/tgu.c
+++ b/drivers/hwtracing/qcom/tgu.c
@@ -18,8 +18,33 @@ static int calculate_array_location(struct tgu_drvdata *drvdata,
 				    int step_index, int operation_index,
 				    int reg_index)
 {
-	return operation_index * (drvdata->num_step) * (drvdata->num_reg) +
-		step_index * (drvdata->num_reg) + reg_index;
+	switch (operation_index) {
+	case TGU_PRIORITY0:
+	case TGU_PRIORITY1:
+	case TGU_PRIORITY2:
+	case TGU_PRIORITY3:
+		return operation_index * (drvdata->num_step) *
+			(drvdata->num_reg) +
+			step_index * (drvdata->num_reg) + reg_index;
+	case TGU_CONDITION_DECODE:
+		return step_index * (drvdata->num_condition_decode) +
+			reg_index;
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static int check_array_location(struct tgu_drvdata *drvdata, int step,
+				int ops, int reg)
+{
+	int result = calculate_array_location(drvdata, step, ops, reg);
+
+	if (result == -EINVAL)
+		dev_err(drvdata->dev, "check arrary location - Fail\n");
+
+	return result;
 }
 
 static ssize_t tgu_dataset_show(struct device *dev,
@@ -30,12 +55,26 @@ static ssize_t tgu_dataset_show(struct device *dev,
 			container_of(attr, struct tgu_attribute, attr);
 	int index;
 
-	index = calculate_array_location(drvdata, tgu_attr->step_index,
-					 tgu_attr->operation_index,
-					 tgu_attr->reg_num);
-
-	return sysfs_emit(buf, "0x%x\n",
-			  drvdata->value_table->priority[index]);
+	index = check_array_location(drvdata, tgu_attr->step_index,
+			tgu_attr->operation_index, tgu_attr->reg_num);
+
+	if (index == -EINVAL)
+		return index;
+
+	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[index]);
+	case TGU_CONDITION_DECODE:
+		return sysfs_emit(buf, "0x%x\n",
+				drvdata->value_table->condition_decode[index]);
+	default:
+		break;
+	}
+	return -EINVAL;
 }
 
 static ssize_t tgu_dataset_store(struct device *dev,
@@ -54,13 +93,31 @@ static ssize_t tgu_dataset_store(struct device *dev,
 		return ret;
 
 	guard(spinlock)(&tgu_drvdata->lock);
-	index = calculate_array_location(tgu_drvdata, tgu_attr->step_index,
+	index = check_array_location(tgu_drvdata, tgu_attr->step_index,
 					 tgu_attr->operation_index,
 					 tgu_attr->reg_num);
 
-	tgu_drvdata->value_table->priority[index] = val;
+	if (index == -EINVAL)
+		return index;
+
+	switch (tgu_attr->operation_index) {
+	case TGU_PRIORITY0:
+	case TGU_PRIORITY1:
+	case TGU_PRIORITY2:
+	case TGU_PRIORITY3:
+		tgu_drvdata->value_table->priority[index] = val;
+		ret = size;
+		break;
+	case TGU_CONDITION_DECODE:
+		tgu_drvdata->value_table->condition_decode[index] = val;
+		ret = size;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
 
-	return size;
+	return ret;
 }
 
 static umode_t tgu_node_visible(struct kobject *kobject,
@@ -77,13 +134,26 @@ static umode_t tgu_node_visible(struct kobject *kobject,
 	if (tgu_attr->step_index >= drvdata->num_step)
 		return SYSFS_GROUP_INVISIBLE;
 
-	if (tgu_attr->reg_num >= drvdata->num_reg)
-		return 0;
+	switch (tgu_attr->operation_index) {
+	case TGU_PRIORITY0:
+	case TGU_PRIORITY1:
+	case TGU_PRIORITY2:
+	case TGU_PRIORITY3:
+		if (tgu_attr->reg_num < drvdata->num_reg)
+			return attr->mode;
+		break;
+	case TGU_CONDITION_DECODE:
+		if (tgu_attr->reg_num < drvdata->num_condition_decode)
+			return attr->mode;
+		break;
+	default:
+		break;
+	}
 
-	return attr->mode;
+	return 0;
 }
 
-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, index;
 
@@ -91,8 +161,10 @@ static void tgu_write_all_hw_regs(struct tgu_drvdata *drvdata)
 	for (i = 0; i < drvdata->num_step; i++) {
 		for (j = 0; j < MAX_PRIORITY; j++) {
 			for (k = 0; k < drvdata->num_reg; k++) {
-				index = calculate_array_location(
+				index = check_array_location(
 							drvdata, i, j, k);
+				if (index == -EINVAL)
+					goto exit;
 
 				writel(drvdata->value_table->priority[index],
 					drvdata->base +
@@ -100,9 +172,23 @@ static void tgu_write_all_hw_regs(struct tgu_drvdata *drvdata)
 			}
 		}
 	}
+
+	for (i = 0; i < drvdata->num_step; i++) {
+		for (j = 0; j < drvdata->num_condition_decode; j++) {
+			index = check_array_location(drvdata, i,
+						TGU_CONDITION_DECODE, j);
+			if (index == -EINVAL)
+				goto exit;
+
+			writel(drvdata->value_table->condition_decode[index],
+				drvdata->base + CONDITION_DECODE_STEP(i, j));
+		}
+	}
 	/* Enable TGU to program the triggers */
 	writel(1, drvdata->base + TGU_CONTROL);
+exit:
 	TGU_LOCK(drvdata->base);
+	return index >= 0 ? 0 : -EINVAL;
 }
 
 static void tgu_set_reg_number(struct tgu_drvdata *drvdata)
@@ -131,18 +217,28 @@ static void tgu_set_steps(struct tgu_drvdata *drvdata)
 	drvdata->num_step = TGU_DEVID_STEPS(devid);
 }
 
+static void tgu_set_conditions(struct tgu_drvdata *drvdata)
+{
+	u32 devid;
+
+	devid = readl(drvdata->base + TGU_DEVID);
+	drvdata->num_condition_decode = TGU_DEVID_CONDITIONS(devid);
+}
+
 static int tgu_enable(struct device *dev)
 {
 	struct tgu_drvdata *drvdata = dev_get_drvdata(dev);
+	int ret;
 
 	guard(spinlock)(&drvdata->lock);
 	if (drvdata->enabled)
 		return -EBUSY;
 
-	tgu_write_all_hw_regs(drvdata);
-	drvdata->enabled = true;
+	ret = tgu_write_all_hw_regs(drvdata);
+	if (!ret)
+		drvdata->enabled = true;
 
-	return 0;
+	return ret;
 }
 
 static void tgu_do_disable(struct tgu_drvdata *drvdata)
@@ -252,6 +348,14 @@ 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,
 };
 
@@ -259,8 +363,8 @@ static int tgu_probe(struct amba_device *adev, const struct amba_id *id)
 {
 	struct device *dev = &adev->dev;
 	struct tgu_drvdata *drvdata;
-	unsigned int *priority;
-	size_t priority_size;
+	unsigned int *priority, *condition;
+	size_t priority_size, condition_size;
 	int ret;
 
 	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
@@ -278,6 +382,7 @@ 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);
 
 	ret = sysfs_create_groups(&dev->kobj, tgu_attr_groups);
 	if (ret) {
@@ -300,6 +405,16 @@ static int tgu_probe(struct amba_device *adev, const struct amba_id *id)
 
 	drvdata->value_table->priority = priority;
 
+	condition_size = drvdata->num_condition_decode * drvdata->num_step;
+
+	condition = devm_kcalloc(dev, condition_size,
+				sizeof(*(drvdata->value_table->condition_decode)),
+				GFP_KERNEL);
+	if (!condition)
+		return -ENOMEM;
+
+	drvdata->value_table->condition_decode = condition;
+
 	drvdata->enabled = false;
 
 	pm_runtime_put(&adev->dev);
diff --git a/drivers/hwtracing/qcom/tgu.h b/drivers/hwtracing/qcom/tgu.h
index 970292f91b02..ca8dfbef0cd2 100644
--- a/drivers/hwtracing/qcom/tgu.h
+++ b/drivers/hwtracing/qcom/tgu.h
@@ -16,6 +16,9 @@
 	((int)FIELD_GET(GENMASK(17, 10), devid_val))
 #define TGU_DEVID_STEPS(devid_val) \
 	((int)FIELD_GET(GENMASK(6, 3), devid_val))
+#define TGU_DEVID_CONDITIONS(devid_val) \
+	((int)FIELD_GET(GENMASK(2, 0), devid_val))
+
 #define TGU_BITS_PER_SIGNAL	4
 #define LENGTH_REGISTER	32
 
@@ -49,6 +52,7 @@
  */
 #define STEP_OFFSET			0x1D8
 #define PRIORITY_START_OFFSET		0x0074
+#define CONDITION_DECODE_OFFSET	0x0050
 #define PRIORITY_OFFSET		0x60
 #define REG_OFFSET			0x4
 
@@ -57,6 +61,9 @@
 	(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 +75,8 @@
 #define STEP_PRIORITY(step_index, reg_num, priority)                     \
 	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), \
@@ -91,6 +100,14 @@
 	 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),\
@@ -98,11 +115,19 @@
 		.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_CONDITION_DECODE,
 };
 
 /* Maximum priority that TGU supports */
@@ -117,6 +142,7 @@ struct tgu_attribute {
 
 struct value_table {
 	unsigned int *priority;
+	unsigned int *condition_decode;
 };
 
 static inline void TGU_LOCK(void __iomem *addr)
@@ -146,6 +172,7 @@ static inline void TGU_UNLOCK(void __iomem *addr)
  * @value_table: Store given value based on relevant parameters
  * @num_reg: Maximum number of registers
  * @num_step: Maximum step size
+ * @num_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
@@ -160,6 +187,7 @@ struct tgu_drvdata {
 	struct value_table *value_table;
 	int num_reg;
 	int num_step;
+	int num_condition_decode;
 };
 
 #endif
-- 
2.34.1




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