[PATCH v10 7/7] qcom-tgu: Add reset node to initialize
Songwei Chai
songwei.chai at oss.qualcomm.com
Mon Jan 26 18:50:35 PST 2026
On 1/13/2026 7:22 PM, Konrad Dybcio wrote:
> On 1/9/26 3:11 AM, Songwei Chai wrote:
>> Add reset node to initialize the value of
>> priority/condition_decode/condition_select/timer/counter nodes.
>>
>> Signed-off-by: Songwei Chai <songwei.chai at oss.qualcomm.com>
>> ---
>
> [...]
>
>> +/* 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)
>> +{
>> + struct tgu_drvdata *drvdata = dev_get_drvdata(dev);
>> + unsigned long value;
>> + int i, j, ret;
>> +
>> + if (kstrtoul(buf, 0, &value) || value == 0)
>> + return -EINVAL;
>
> Your documentation blurb promises that only 1 is accepted, but this is not
> the case. I think the previous additions had a similar flaw
I’ll fix this to only accept 1 and review the previous additions
for similar issues.
>
>> +
>> + if (!drvdata->enable) {
>
> I think this check needs to be made under a lock, otherwise something else
> may pull the plug inbetween
Will move "guard(spinlock)(&drvdata->lock);" before "drvdata->enable" check.
>
>> + ret = pm_runtime_get_sync(drvdata->dev);
>> + if (ret < 0) {
>> + pm_runtime_put(drvdata->dev);
>> + return ret;
>> + }
>> + }
>> +
>> + guard(spinlock)(&drvdata->lock);
>> + TGU_UNLOCK(drvdata->base);
>> +
>> + writel(0, drvdata->base + TGU_CONTROL);
>> +
>> + TGU_LOCK(drvdata->base);
>
> This is tgu_disable()
will use tgu_disable instead.
>
>> +
>> + 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) */
>
> One \t too much
will update.
>
>> + 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;
>
> This is unreadable, take a pointer to condition_decode[]
sure.
>
>> + }
>> + }
>> +
>> + 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) *
>> + sizeof(unsigned int));
>> +
>> + if (drvdata->value_table->counter)
>> + memset(drvdata->value_table->counter, 0,
>> + (drvdata->max_step) *
>> + (drvdata->max_counter) *
>> + sizeof(unsigned int));
>
> This is similarly difficult to read with almost random indentation
>
I agree, the indentation hurts readability. I’ll rework this to make the
expression clearer.
> Konrad
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