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

From: Krishna Chaitanya Chundru
Date: Thu Nov 09 2023 - 04:32:30 EST



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.

- Krishna Chaitanya