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[PATCH v2 2/3] coresight: cti: Add PM runtime call in enable_store

James Clark posted 3 patches 2 years, 8 months ago
There is a newer version of this series
[PATCH v2 2/3] coresight: cti: Add PM runtime call in enable_store
Posted by James Clark 2 years, 8 months ago 
From: Mao Jinlong <quic_jinlmao@quicinc.com>

In commit 6746eae4bbad ("coresight: cti: Fix hang in cti_disable_hw()")
PM runtime calls are removed from cti_enable_hw/cti_disable_hw. When
enabling CTI by writing enable sysfs node, clock for accessing CTI
register won't be enabled. Device will crash due to register access
issue. Add PM runtime call in enable_store to fix this issue.

Fixes: 6746eae4bbad ("coresight: cti: Fix hang in cti_disable_hw()")
Signed-off-by: Mao Jinlong <quic_jinlmao@quicinc.com>
[Change to only call pm_runtime_put if a disable happened]
Signed-off-by: James Clark <james.clark@arm.com>
---
 drivers/hwtracing/coresight/coresight-cti-sysfs.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-cti-sysfs.c b/drivers/hwtracing/coresight/coresight-cti-sysfs.c
index 6d59c815ecf5..71e7a8266bb3 100644
--- a/drivers/hwtracing/coresight/coresight-cti-sysfs.c
+++ b/drivers/hwtracing/coresight/coresight-cti-sysfs.c
@@ -108,10 +108,19 @@ static ssize_t enable_store(struct device *dev,
 	if (ret)
 		return ret;
 
-	if (val)
+	if (val) {
+		ret = pm_runtime_resume_and_get(dev->parent);
+		if (ret)
+			return ret;
 		ret = cti_enable(drvdata->csdev);
-	else
+		if (ret)
+			pm_runtime_put(dev->parent);
+	} else {
 		ret = cti_disable(drvdata->csdev);
+		if (!ret)
+			pm_runtime_put(dev->parent);
+	}
+
 	if (ret)
 		return ret;
 	return size;
-- 
2.25.1
Re: [PATCH v2 2/3] coresight: cti: Add PM runtime call in enable_store
Posted by Suzuki K Poulose 2 years, 8 months ago 
On 06/01/2023 15:23, James Clark wrote:
> From: Mao Jinlong <quic_jinlmao@quicinc.com>
> 
> In commit 6746eae4bbad ("coresight: cti: Fix hang in cti_disable_hw()")
> PM runtime calls are removed from cti_enable_hw/cti_disable_hw. When
> enabling CTI by writing enable sysfs node, clock for accessing CTI
> register won't be enabled. Device will crash due to register access
> issue. Add PM runtime call in enable_store to fix this issue.
> 
> Fixes: 6746eae4bbad ("coresight: cti: Fix hang in cti_disable_hw()")
> Signed-off-by: Mao Jinlong <quic_jinlmao@quicinc.com>
> [Change to only call pm_runtime_put if a disable happened]
> Signed-off-by: James Clark <james.clark@arm.com>
> ---
>   drivers/hwtracing/coresight/coresight-cti-sysfs.c | 13 +++++++++++--
>   1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-cti-sysfs.c b/drivers/hwtracing/coresight/coresight-cti-sysfs.c
> index 6d59c815ecf5..71e7a8266bb3 100644
> --- a/drivers/hwtracing/coresight/coresight-cti-sysfs.c
> +++ b/drivers/hwtracing/coresight/coresight-cti-sysfs.c
> @@ -108,10 +108,19 @@ static ssize_t enable_store(struct device *dev,
>   	if (ret)
>   		return ret;
>   
> -	if (val)
> +	if (val) {
> +		ret = pm_runtime_resume_and_get(dev->parent);
> +		if (ret)
> +			return ret;
>   		ret = cti_enable(drvdata->csdev);
> -	else
> +		if (ret)
> +			pm_runtime_put(dev->parent);
> +	} else {
>   		ret = cti_disable(drvdata->csdev);
> +		if (!ret)
> +			pm_runtime_put(dev->parent);
> +	}
> +
>   	if (ret)
>   		return ret;
>   	return size;

Looks good to me.

@Mao Jinolong,

Are you able to test the patches 1 & 2 and confirm they solve your issue ?

Suzuki
Re: [PATCH v2 2/3] coresight: cti: Add PM runtime call in enable_store
Posted by Jinlong Mao 2 years, 8 months ago 
On 1/10/2023 12:47 AM, Suzuki K Poulose wrote:
> On 06/01/2023 15:23, James Clark wrote:
>> From: Mao Jinlong <quic_jinlmao@quicinc.com>
>>
>> In commit 6746eae4bbad ("coresight: cti: Fix hang in cti_disable_hw()")
>> PM runtime calls are removed from cti_enable_hw/cti_disable_hw. When
>> enabling CTI by writing enable sysfs node, clock for accessing CTI
>> register won't be enabled. Device will crash due to register access
>> issue. Add PM runtime call in enable_store to fix this issue.
>>
>> Fixes: 6746eae4bbad ("coresight: cti: Fix hang in cti_disable_hw()")
>> Signed-off-by: Mao Jinlong <quic_jinlmao@quicinc.com>
>> [Change to only call pm_runtime_put if a disable happened]
>> Signed-off-by: James Clark <james.clark@arm.com>
>> ---
>>   drivers/hwtracing/coresight/coresight-cti-sysfs.c | 13 +++++++++++--
>>   1 file changed, 11 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/hwtracing/coresight/coresight-cti-sysfs.c 
>> b/drivers/hwtracing/coresight/coresight-cti-sysfs.c
>> index 6d59c815ecf5..71e7a8266bb3 100644
>> --- a/drivers/hwtracing/coresight/coresight-cti-sysfs.c
>> +++ b/drivers/hwtracing/coresight/coresight-cti-sysfs.c
>> @@ -108,10 +108,19 @@ static ssize_t enable_store(struct device *dev,
>>       if (ret)
>>           return ret;
>>   -    if (val)
>> +    if (val) {
>> +        ret = pm_runtime_resume_and_get(dev->parent);
>> +        if (ret)
>> +            return ret;
>>           ret = cti_enable(drvdata->csdev);
>> -    else
>> +        if (ret)
>> +            pm_runtime_put(dev->parent);
>> +    } else {
>>           ret = cti_disable(drvdata->csdev);
>> +        if (!ret)
>> +            pm_runtime_put(dev->parent);
>> +    }
>> +
>>       if (ret)
>>           return ret;
>>       return size;
>
> Looks good to me.
>
> @Mao Jinolong,
>
> Are you able to test the patches 1 & 2 and confirm they solve your 
> issue ?

Hi Suzuki,

Tested from my side. Patch 1 & 2 can solve the issue when enable CTI by 
writing 1 to enable sysfs node.

Thanks
Jinlong Mao
>
> Suzuki
Re: [PATCH v2 2/3] coresight: cti: Add PM runtime call in enable_store
Posted by James Clark 2 years, 8 months ago 

On 10/01/2023 05:56, Jinlong Mao wrote:
> 
> On 1/10/2023 12:47 AM, Suzuki K Poulose wrote:
>> On 06/01/2023 15:23, James Clark wrote:
>>> From: Mao Jinlong <quic_jinlmao@quicinc.com>
>>>
>>> In commit 6746eae4bbad ("coresight: cti: Fix hang in cti_disable_hw()")
>>> PM runtime calls are removed from cti_enable_hw/cti_disable_hw. When
>>> enabling CTI by writing enable sysfs node, clock for accessing CTI
>>> register won't be enabled. Device will crash due to register access
>>> issue. Add PM runtime call in enable_store to fix this issue.
>>>
>>> Fixes: 6746eae4bbad ("coresight: cti: Fix hang in cti_disable_hw()")
>>> Signed-off-by: Mao Jinlong <quic_jinlmao@quicinc.com>
>>> [Change to only call pm_runtime_put if a disable happened]
>>> Signed-off-by: James Clark <james.clark@arm.com>
>>> ---
>>>   drivers/hwtracing/coresight/coresight-cti-sysfs.c | 13 +++++++++++--
>>>   1 file changed, 11 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/hwtracing/coresight/coresight-cti-sysfs.c
>>> b/drivers/hwtracing/coresight/coresight-cti-sysfs.c
>>> index 6d59c815ecf5..71e7a8266bb3 100644
>>> --- a/drivers/hwtracing/coresight/coresight-cti-sysfs.c
>>> +++ b/drivers/hwtracing/coresight/coresight-cti-sysfs.c
>>> @@ -108,10 +108,19 @@ static ssize_t enable_store(struct device *dev,
>>>       if (ret)
>>>           return ret;
>>>   -    if (val)
>>> +    if (val) {
>>> +        ret = pm_runtime_resume_and_get(dev->parent);
>>> +        if (ret)
>>> +            return ret;
>>>           ret = cti_enable(drvdata->csdev);
>>> -    else
>>> +        if (ret)
>>> +            pm_runtime_put(dev->parent);
>>> +    } else {
>>>           ret = cti_disable(drvdata->csdev);
>>> +        if (!ret)
>>> +            pm_runtime_put(dev->parent);
>>> +    }
>>> +
>>>       if (ret)
>>>           return ret;
>>>       return size;
>>
>> Looks good to me.
>>
>> @Mao Jinolong,
>>
>> Are you able to test the patches 1 & 2 and confirm they solve your
>> issue ?
> 
> Hi Suzuki,
> 
> Tested from my side. Patch 1 & 2 can solve the issue when enable CTI by
> writing 1 to enable sysfs node.

Thanks, I added your tested-by tag on patches 1 + 2.

Patchew 2.1-devel-b67e4c2

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