Re: [Patch 0/5] Support Autonomous Selection mode in cppc_cpufreq

Sumit Gupta
2025-02-21T13:14:47Z

On 19/02/25 00:53, Rafael J. Wysocki wrote:
>
> There seems to be some quite fundamental disagreement on how this
> should be done, so I'm afraid I cannot do much about it ATM.
>
> Please agree on a common approach and come back to me when you are ready.
>
> Sending two concurrent patchsets under confusingly similar names again
> and again isn't particularly helpful.
>
> Thanks!

Hi Rafael,

Thank you for looking into this.

Hi Lifeng,

As per the discussion, we can make the driver future extensible and
also can optimize the register read/write access.

I gave some thought and below is my proposal.

1) Pick 'Patch 1-7' from your patch series [1] which optimize API's
to read/write a cpc register.

2) Pick my patches in [2]:
- Patch 1-4: Keep all cpc registers together under acpi_cppc sysfs.
Also, update existing API's to read/write regs in batch.
- Patch 5: Creates 'cppc_cpufreq_epp_driver' instance for booting
all CPU's in Auto mode and set registers with right values.
They can be updated after boot from sysfs to change hints to HW.
I can use the optimized API's from [1] where required in [2].

Let me know if you are okay with this proposal.
I can also send an updated patch series with all the patches combined?

[1]
https://lore.kernel.org/all/20250206131428.3261578-1-zhenglifeng1@huawei.com/
[2] https://lore.kernel.org/lkml/20250211103737.447704-1-sumitg@nvidia.com/

Regards,
Sumit Gupta