RE: [PATCH] net: stmmac: fix MAC not working when system resume back with WoL enabled

From: Joakim Zhang <qiangqing.zhang@nxp.com>
To: Russell King <linux@armlinux.org.uk>
Cc: Andrew Lunn <andrew@lunn.ch>, Vladimir Oltean <olteanv@gmail.com>,
	"peppe.cavallaro@st.com" <peppe.cavallaro@st.com>,
	"alexandre.torgue@foss.st.com" <alexandre.torgue@foss.st.com>,
	"joabreu@synopsys.com" <joabreu@synopsys.com>,
	"davem@davemloft.net" <davem@davemloft.net>,
	"kuba@kernel.org" <kuba@kernel.org>,
	"mcoquelin.stm32@gmail.com" <mcoquelin.stm32@gmail.com>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	"f.fainelli@gmail.com" <f.fainelli@gmail.com>,
	"hkallweit1@gmail.com" <hkallweit1@gmail.com>,
	dl-linux-imx <linux-imx@nxp.com>
Subject: RE: [PATCH] net: stmmac: fix MAC not working when system resume back with WoL enabled
Date: Mon, 6 Sep 2021 10:41:48 +0000	[thread overview]
Message-ID: <DB8PR04MB67958E22A85B15FFCA7CDA70E6D29@DB8PR04MB6795.eurprd04.prod.outlook.com> (raw)
In-Reply-To: <YTXgqBRMRvYdPyJU@shell.armlinux.org.uk>

Hi Russell,

> -----Original Message-----
> From: Russell King <linux@armlinux.org.uk>
> Sent: 2021年9月6日 17:35
> To: Joakim Zhang <qiangqing.zhang@nxp.com>
> Cc: Andrew Lunn <andrew@lunn.ch>; Vladimir Oltean <olteanv@gmail.com>;
> peppe.cavallaro@st.com; alexandre.torgue@foss.st.com;
> joabreu@synopsys.com; davem@davemloft.net; kuba@kernel.org;
> mcoquelin.stm32@gmail.com; netdev@vger.kernel.org; f.fainelli@gmail.com;
> hkallweit1@gmail.com; dl-linux-imx <linux-imx@nxp.com>
> Subject: Re: [PATCH] net: stmmac: fix MAC not working when system resume
> back with WoL enabled
> 
> Hi,
> 
> On Mon, Sep 06, 2021 at 02:29:30AM +0000, Joakim Zhang wrote:
> > Hi Russell,
> >
> > > -----Original Message-----
> > > +		/* Re-apply the link parameters so that all the settings get
> > > +		 * restored to the MAC.
> > > +		 */
> > > +		phylink_mac_initial_config(pl, true);
> > > +		phylink_enable_and_run_resolve(pl,
> PHYLINK_DISABLE_MAC_WOL);
> >
> > There is no "phylink_enable_and_run_resolve " sysbol, I guess you want do
> below operations in this function:
> > 	clear_bit(PHYLINK_DISABLE_MAC_WOL, &pl->phylink_disable_state);
> > 	phylink_run_resolve(pl);
> 
> Yes, that is correct.
> 
> Please let me know whether that works for you.

Thanks Russell, it works as we are expected, I test both MAC-based WoL active and inactive cases.

And I get the point you mentioned before, if link parameters changed during system suspended, what would happen?
I tried both FEC and STMMAC, the system can't be waked up via remote magic packets!!!
I have not think about this scenario before....

Since net-next is closed, so I would cook a patch set (keep you as the phylink patch author) after it re-open, could you
accept it? Or you plan to prepare this patch set for stmmac?

There is also a problem, we need a fix for LTS (5.10, 5.15), above patch set should go to 5.16, do you have any suggestion?

Best Regards,
Joakim Zhang