[PATCH v13 4/7] qcom-tgu: Add TGU decode support
Jie Gan
jie.gan at oss.qualcomm.com
Thu Apr 2 03:02:43 PDT 2026
On 4/2/2026 5:28 PM, Songwei Chai wrote:
> 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.
>
> Reviewed-by: Jie Gan <jie.gan at oss.qualcomm.com>
> 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 | 27 +++
> 3 files changed, 170 insertions(+), 21 deletions(-)
>
> diff --git a/Documentation/ABI/testing/sysfs-bus-amba-devices-tgu b/Documentation/ABI/testing/sysfs-bus-amba-devices-tgu
> index 223873789ca6..4ef0d696d3d0 100644
> --- a/Documentation/ABI/testing/sysfs-bus-amba-devices-tgu
> +++ b/Documentation/ABI/testing/sysfs-bus-amba-devices-tgu
> @@ -14,3 +14,10 @@ KernelVersion: 7.1
> 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: April 2026
> +KernelVersion: 7.1
> +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 7d69986c3e3d..5b37eb10f863 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");
s/arrary/array
Thanks,
Jie
> +
> + 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)
> @@ -131,16 +217,26 @@ 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);
> - drvdata->enabled = true;
>
> - tgu_write_all_hw_regs(drvdata);
> + 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)
> @@ -262,6 +358,14 @@ 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,
> };
>
> @@ -269,8 +373,8 @@ 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);
> @@ -288,6 +392,7 @@ 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) {
> @@ -310,6 +415,16 @@ 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 df570c89ffd7..987ea07bd618 100644
> --- a/drivers/hwtracing/qcom/tgu.h
> +++ b/drivers/hwtracing/qcom/tgu.h
> @@ -16,6 +16,8 @@
> ((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 +51,7 @@
> */
> #define STEP_OFFSET 0x1D8
> #define PRIORITY_START_OFFSET 0x0074
> +#define CONDITION_DECODE_OFFSET 0x0050
> #define PRIORITY_OFFSET 0x60
> #define REG_OFFSET 0x4
>
> @@ -57,6 +60,9 @@
> (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 +74,8 @@
> #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 +99,14 @@
> 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 +114,19 @@
> .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 +141,7 @@ struct tgu_attribute {
>
> struct value_table {
> unsigned int *priority;
> + unsigned int *condition_decode;
> };
>
> static inline void TGU_LOCK(void __iomem *addr)
> @@ -146,6 +171,7 @@ 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 +186,7 @@ struct tgu_drvdata {
> struct value_table *value_table;
> int num_reg;
> int num_step;
> + int num_condition_decode;
> };
>
> #endif
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