[PATCH v2 0/3] phy: qcom-qmp-pcie: Add support to keep refclk always on

Konrad Dybcio konrad.dybcio at linaro.org
Thu Nov 9 05:57:58 PST 2023



On 11/9/23 10:32, Krishna Chaitanya Chundru wrote:
> 
> On 11/8/2023 3:27 AM, Konrad Dybcio wrote:
>>
>>
>> On 11/7/23 13:26, Krishna chaitanya chundru wrote:
>>> This series adds support to provide refclk to endpoint even in low
>>> power states.
>>>
>>> Due to some platform specific issues with CLKREQ signal, it is not being
>>> propagated to the host and as host doesn't know the clkreq signal host is
>>> not sending refclk. Due to this endpoint is seeing linkdown and going
>>> to bad state.
>>> To avoid those ref clk should be provided always to the endpoint. The
>>> issue is coming only when ep intiates the L1.1 or L1.2 exit and clkreq
>>> is not being propagated properly to the host.
>> I'm gonna sound like a broken record, but:
>>
>> How much power does this consume? Would it matter if we kept this
>> clock always-on for all platforms with this version of the phy?
>>
>> Konrad
> 
> We see about 22mw extra power consumption with refclk always on.
> 
> We can't keep this property always on as there is impact on power consumption.
Ooeheh, that's not far away from a low-clocked efficiency CPU core..

Thanks for checking!

Konrad



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