Re: [PATCH v2 3/3] pmdommain: add support system-wide resume latency constraints

From: Kevin Hilman

Date: Thu Feb 26 2026 - 13:05:33 EST


Kendall Willis <k-willis@xxxxxx> writes:

> Hi Kevin,
> On 2/5/26 18:29, Kevin Hilman (TI) wrote:
>> In addition to checking for CPU latency constraints when checking if
>> OK to power down a domain, also check for QoS latency constraints in
>> all devices of a domain and use that in determining the final latency
>> constraint to use for the domain.
>>
>> Since cpu_system_power_down_ok() is used for system-wide suspend, the
>> per-device constratints are only relevant if the LATENCY_SYS QoS flag
>> is set.
>>
>> Signed-off-by: Kevin Hilman (TI) <khilman@xxxxxxxxxxxx>
>> ---
>
> Were you planning to also check the CPU devices QoS latency constraints
> in the cpu_system_power_down_ok function? At present, this patch does
> not add that functionality so if the PM_QOS_FLAG_LATENCY_SYS is present
> for a CPU device, the QoS latency is not taken into account.

I did not add that functionality because the CPUs are managed by the new
system-wide /dev/cpu_wakeup_latency, which is already checked.

Kevin