linux-kernel - Re: [IMX] [DRM]: help in analyzing clock

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Date:   Thu, 11 Jul 2019 20:59:54 +0530
From:   Pintu Agarwal <pintu.ping@...il.com>
To:     Fabio Estevam <festevam@...il.com>, s.hauer@...gutronix.de,
        p.zabel@...gutronix.de
Cc:     open list <linux-kernel@...r.kernel.org>,
        "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" 
        <linux-arm-kernel@...ts.infradead.org>,
        Kernelnewbies <kernelnewbies@...nelnewbies.org>,
        linux-pm@...r.kernel.org
Subject: Re: [IMX] [DRM]: help in analyzing clock_summary rate difference

Hi,

I need one general help in analyzing difference in clock_summary rate
before and after the system resume.

I am using custom IMX7 board with 4.9 Kernel.
With this I am trying to support some functionality during suspend/resume.
I am trying to analyze clk_summary from:
# cat /sys/kernel/debug/clk/clk_summary

I observed that there are difference in "clock rate" after system
resume and module install. However the enable/prepare count remains
the same.

Since I am not much familiar with clock framework, I am looking for
some help to analyze this issue. It's an internal issue.

May be someone which is familiar with clock analysis or fixed the
similar issue earlier can give me some guidance.
What does the difference in clock rate indicates?
What analysis can be done to narrow down the root cause?
Any example of reference could be helpful to understand.

Thank You!
Regards,
Pintu