Re: [PATCH] net: stmmac: don't stop RXC during LPI

[Jakub Kicinski]

On Sun, 23 Jan 2022 22:12:45 +0800 Jisheng Zhang wrote:
> I met can't receive rx pkt issue with below steps:
> 0.plug in ethernet cable then boot normal and get ip from dhcp server
> 1.quickly hotplug out then hotplug in the ethernet cable
> 2.trigger the dhcp client to renew lease
> 
> tcpdump shows that the request tx pkt is sent out successfully,
> but the mac can't receive the rx pkt.
> 
> The issue can easily be reproduced on platforms with PHY_POLL external
> phy. If we don't allow the phy to stop the RXC during LPI, the issue
> is gone. I think it's unsafe to stop the RXC during LPI because the mac
> needs RXC clock to support RX logic.
> 
> And the 2nd param clk_stop_enable of phy_init_eee() is a bool, so use
> false instead of 0.

FWIW this is marked Changes Requested in pw, TBH I'm not sure what 
the conclusion is but if the patch is good please try to fold the
information requested in the discussion into the commit msg and repost.