Re: [PATCH v3 7/7] coresight-tgu: add reset node to initialize
From: Mike Leach <hidden>
Date: 2025-03-07 13:33:50
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linux-arm-msm, linux-devicetree, lkml
Hi, On Thu, 27 Feb 2025 at 09:27, songchai [off-list ref] wrote:
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From: Songwei Chai <redacted> Add reset node to initialize the value of priority/condition_decode/condition_select/timer/counter nodes Signed-off-by: Songwei Chai <redacted> Signed-off-by: songchai <redacted> --- .../testing/sysfs-bus-coresight-devices-tgu | 7 ++ drivers/hwtracing/coresight/coresight-tgu.c | 79 +++++++++++++++++++ 2 files changed, 86 insertions(+)diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tgu b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tgu index d88d05fbff43..8fb5afd7c655 100644 --- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tgu +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tgu@@ -42,3 +42,10 @@ KernelVersion 6.15 Contact: Jinlong Mao (QUIC) <quic_jinlmao@quicinc.com>, Sam Chai (QUIC) <quic_songchai@quicinc.com> Description: (RW) Set/Get the counter value with specific step for TGU. + +What: /sys/bus/coresight/devices/<tgu-name>/reset_tgu +Date: February 2025 +KernelVersion 6.15 +Contact: Jinlong Mao (QUIC) <quic_jinlmao@quicinc.com>, Sam Chai (QUIC) <quic_songchai@quicinc.com> +Description: + (Write) Reset the dataset for TGU.
Document the value needed to initiate the reset.
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diff --git a/drivers/hwtracing/coresight/coresight-tgu.c b/drivers/hwtracing/coresight/coresight-tgu.c index 693d632fb079..b36ced761c0d 100644 --- a/drivers/hwtracing/coresight/coresight-tgu.c +++ b/drivers/hwtracing/coresight/coresight-tgu.c@@ -343,6 +343,84 @@ static ssize_t enable_tgu_store(struct device *dev, } static DEVICE_ATTR_RW(enable_tgu); +/* reset_tgu_store - Reset Trace and Gating Unit (TGU) configuration. */ +static ssize_t reset_tgu_store(struct device *dev, + struct device_attribute *attr, const char *buf, + size_t size) +{ + unsigned long value; + struct tgu_drvdata *drvdata = dev_get_drvdata(dev->parent); + int i, j, ret; + + if (kstrtoul(buf, 0, &value)) + return -EINVAL; +
Check "value" here and bail out with an error code if 0.
+ if (!drvdata->enable) {
+ ret = pm_runtime_get_sync(drvdata->dev);
+ if (ret < 0) {
+ pm_runtime_put(drvdata->dev);
+ return ret;
+ }
+ }
+
+ spin_lock(&drvdata->spinlock);
+ CS_UNLOCK(drvdata->base);
+
+ if (value) {drop this line
+ tgu_writel(drvdata, 0, TGU_CONTROL);
+
+ if (drvdata->value_table->priority)
+ memset(drvdata->value_table->priority, 0,
+ MAX_PRIORITY * drvdata->max_step *
+ drvdata->max_reg * sizeof(unsigned int));
+
+ if (drvdata->value_table->condition_decode)
+ memset(drvdata->value_table->condition_decode, 0,
+ drvdata->max_condition_decode * drvdata->max_step *
+ sizeof(unsigned int));
+
+ /* Initialize all condition registers to NOT(value=0x1000000) */
+ for (i = 0; i < drvdata->max_step; i++) {
+ for (j = 0; j < drvdata->max_condition_decode; j++) {
+ drvdata->value_table
+ ->condition_decode[calculate_array_location(
+ drvdata, i, TGU_CONDITION_DECODE, j)] =
+ 0x1000000;
+ }
+ }
+
+ if (drvdata->value_table->condition_select)
+ memset(drvdata->value_table->condition_select, 0,
+ drvdata->max_condition_select * drvdata->max_step *
+ sizeof(unsigned int));
+
+ if (drvdata->value_table->timer)
+ memset(drvdata->value_table->timer, 0,
+ (drvdata->max_step) *
+ (drvdata->max_timer_counter) *
+ sizeof(unsigned int));
+
+ if (drvdata->value_table->counter)
+ memset(drvdata->value_table->counter, 0,
+ (drvdata->max_step) *
+ (drvdata->max_timer_counter) *
+ sizeof(unsigned int));
+
+ dev_dbg(dev, "Coresight-TGU reset complete\n");
+ } else {
+ dev_dbg(dev, "Coresight-TGU invalid input\n");not needed if early exit on input errror
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+ } + + CS_LOCK(drvdata->base); + + drvdata->enable = false; + spin_unlock(&drvdata->spinlock); + pm_runtime_put(drvdata->dev); + + return size; +} +static DEVICE_ATTR_WO(reset_tgu); + static const struct coresight_ops_helper tgu_helper_ops = { .enable = tgu_enable, .disable = tgu_disable,@@ -354,6 +432,7 @@ static const struct coresight_ops tgu_ops = { static struct attribute *tgu_common_attrs[] = { &dev_attr_enable_tgu.attr, + &dev_attr_reset_tgu.attr, NULL, };
Regards Mike -- Mike Leach Principal Engineer, ARM Ltd. Manchester Design Centre. UK