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Date:   Wed, 30 Nov 2022 11:23:42 +0000
From:   "Russell King (Oracle)" <linux@armlinux.org.uk>
To:     Clark Wang <xiaoning.wang@nxp.com>
Cc:     peppe.cavallaro@st.com, alexandre.torgue@foss.st.com,
        joabreu@synopsys.com, davem@davemloft.net, edumazet@google.com,
        kuba@kernel.org, pabeni@redhat.com, mcoquelin.stm32@gmail.com,
        andrew@lunn.ch, hkallweit1@gmail.com, netdev@vger.kernel.org,
        linux-stm32@st-md-mailman.stormreply.com,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] net: phylink: add sync flag mac_ready to fix resume
 issue with WoL enabled
Message-ID: <Y4c9PlfEC17pVE08@shell.armlinux.org.uk>
References: <20221130111148.1064475-1-xiaoning.wang@nxp.com>
 <20221130111148.1064475-2-xiaoning.wang@nxp.com>
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Sender: Russell King (Oracle) <linux@armlinux.org.uk>
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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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