Re: [PATCH net-next V1 3/4] net: stmmac: Reconfigure the PHY WOL settings in stmmac_resume()

[Andrew Lunn <andrew@lunn.ch>]

On Wed, Jun 23, 2021 at 10:06:44AM +0000, Voon, Weifeng wrote:
> > > From: Muhammad Husaini Zulkifli <muhammad.husaini.zulkifli@intel.com>
> > >
> > > After PHY received a magic packet, the PHY WOL event will be triggered
> > > then PHY WOL event interrupt will be disarmed.
> > > Ethtool settings will remain with WOL enabled after a S3/S4 suspend
> > > resume cycle as expected. Hence,the driver should reconfigure the PHY
> > > settings to reenable/disable WOL depending on the ethtool WOL settings
> > > in the resume flow.
> > 
> > Please could you explain this a bit more? I'm wondering if you have a
> > PHY driver bug. PHY WOL should remain enabled until it is explicitly
> > disabled.
> > 
> > 	Andrew
> 
> Let's take Marvell 1510 as example. 
> 
> As explained in driver/net/phy/marvell.c
> 1773 >------->-------/* If WOL event happened once, the LED[2] interrupt pin
> 1774 >------->------- * will not be cleared unless we reading the interrupt status
> 1775 >------->------- * register. 
> 
> The WOL event will not able trigger again if the driver does not clear
> the interrupt status.
> Are we expecting PHY driver will automatically clears the interrupt
> status rather than trigger from the MAC driver?

So you are saying the interrupt it getting discarded? I would of
though it is this interrupt which brings to system out of suspend, and
it should trigger the usual action, i.e. call the interrupt
handler. That should then clear the interrupt.

	 Andrew