[PATCH V2 1/3] ufs: core: Add CPU latency QoS support for ufs driver

Bart Van Assche bvanassche at acm.org
Tue Dec 5 09:11:56 PST 2023


On 12/4/23 21:58, Naresh Maramaina wrote:
> On 12/5/2023 12:30 AM, Bart Van Assche wrote:
>> On 12/4/23 06:30, Maramaina Naresh wrote:
>>> +    /* This capability allows the host controller driver to use the 
>>> PM QoS
>>> +     * feature.
>>> +     */
>>> +    UFSHCD_CAP_PM_QOS                = 1 << 13,
>>>   };
>>
>> Why does it depend on the host driver whether or not PM QoS is
>> enabled? Why isn't it enabled unconditionally?
> 
> For some platform vendors power KPI might be more important than random 
> io KPI. Hence this flag is disabled by default and can be enabled based 
> on platform requirement.

How about leaving this flag out unless if a host vendor asks explicitly
for this flag?
>>
>>> + * @pm_qos_req: PM QoS request handle
>>> + * @pm_qos_init: flag to check if pm qos init completed
>>>    */
>>
>> Documentation for pm_qos_init is missing.
>>
> Sorry, i didn't get your comment, i have already added documentation for 
> @pm_qos_init, @pm_qos_req variable as above. Do you want me to add this 
> information some where else as well?

Oops, I meant 'qos_vote'.

Thanks,

Bart.




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