Re: [PATCH 1/2] net: phylink: add sync flag mac_ready to fix resume issue with WoL enabled

From: Russell King (Oracle)
Date: Wed Nov 30 2022 - 06:25:12 EST


On Wed, Nov 30, 2022 at 07:11:47PM +0800, Clark Wang wrote:
> Issue we met:
> On some platforms, mac cannot work after resumed from the suspend with WoL
> enabled.
>
> The cause of the issue:
> 1. phylink_resolve() is in a workqueue which will not be executed immediately.
> This is the call sequence:
> phylink_resolve()->phylink_link_up()->pl->mac_ops->mac_link_up()
> For stmmac driver, mac_link_up() will set the correct speed/duplex...
> values which are from link_state.
> 2. In stmmac_resume(), it will call stmmac_hw_setup() after called the
> phylink_resume(). stmmac_core_init() is called in function stmmac_hw_setup(),

... and that is where the problem is. Don't call phylink_resume() before
your hardware is ready to see a link-up event.

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