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Date:   Thu, 18 Aug 2022 03:20:02 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Wei Fang <wei.fang@nxp.com>
Cc:     "hkallweit1@gmail.com" <hkallweit1@gmail.com>,
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Subject: Re: [PATCH net 1/2] dt: ar803x: Document disable-hibernation property
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> Hi Andrew,
> 
> 	Your suggestion is indeed an effective solution, but I checked both the datasheet
> and the driver of AR803x PHYs and found that the qca,clk-out-frequency and the
> qca,keep-pll-enabled properties are associated with the CLK_25M pin of AR803x PHYs.
> But there is a case that CLK_25M pin is not used on some platforms.
> Taking our i.MX8DXL platform as an example, the stmmac and AR8031 PHY are applied
> on this platform, but the CLK_25M pin of AR8031 is not used. So when I used the method
> you mentioned above, it did not work as expected. In this case, we can only disable the
> hibernation mode of AR803x PHYs and keep the RX_CLK always outputting a valid clock
> so that the stmmac can complete the software reset operation.

What happens to the RX_CLK when you unplug the cable? It is no longer
receiving anything, so i would expect the RX_CLK to stop ticking. Does
that cause problems for the MAC?

     Andrew