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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