Re: [PATCH v6 6/6] PCI: qcom: Add OPP support to scale performance state of power domain

Krishna Chaitanya Chundru
2024-01-16T05:07:39Z

On 1/12/2024 10:20 PM, Bjorn Helgaas wrote:
> On Fri, Jan 12, 2024 at 07:52:05PM +0530, Krishna chaitanya chundru wrote:
>> QCOM Resource Power Manager-hardened (RPMh) is a hardware block which
>> maintains hardware state of a regulator by performing max aggregation of
>> the requests made by all of the processors.
>>
>> PCIe controller can operate on different RPMh performance state of power
>> domain based up on the speed of the link. And this performance state varies
>> from target to target.
>>
>> It is manadate to scale the performance state based up on the PCIe speed
>> link operates so that SoC can run under optimum power conditions.
>>
>> Add Operating Performance Points(OPP) support to vote for RPMh state based
>> upon GEN speed link is operating.
>
> Thanks for this "OPP" expansion! Maybe "GEN" is unnecessary in this
> sentence? And below, could be replaced with actual speeds?
>
ACK
>> OPP can handle ICC bw voting also, so move icc bw voting through opp
>> framework if opp entries are present.
>
> s/opp/OPP/ to match
> s/icc/ICC/ similarly (and perhaps expand once)
> Also below in comments, etc.
>
ACK.

-Krishna Chaitanya.
>> In PCIe certain gen speeds like GEN1x2 & GEN2X1 or GEN3x2 & GEN4x1 use
>> same icc bw and has frequency, so use frequency based search to reduce
>> number of entries in the opp table.
>>
>> Don't initialize icc if opp is supported.
>
> Bjorn