RE: [PATCH 0/3] net: fec: Reset ethernet PHY whenever the enet_out clock

Duan Andy
2015-12-01T07:33:04Z

From: Lothar Waßmann <LW@KARO-electronics.de> Sent: Tuesday, December 01, 2015 3:25 PM
> To: Duan Fugang-B38611
> Cc: Andrew Lunn; David S. Miller; Estevam Fabio-R49496; Greg Ungerer;
> Kevin Hao; Lucas Stach; Philippe Reynes; Richard Cochran; Russell King;
> Sascha Hauer; Stefan Agner; linux-kernel@vger.kernel.org;
> netdev@vger.kernel.org; Jeff Kirsher; Uwe Kleine-K?nig
> Subject: Re: [PATCH 0/3] net: fec: Reset ethernet PHY whenever the
> enet_out clock
>
> Hi,
>
> > From: Lothar Waßmann <LW@KARO-electronics.de> Sent: Monday, November
> > 30, 2015 7:33 PM
> > > To: Andrew Lunn; David S. Miller; Estevam Fabio-R49496; Greg
> > > Ungerer; Kevin Hao; Lothar Waßmann; Lucas Stach; Duan Fugang-B38611;
> > > Philippe Reynes; Richard Cochran; Russell King; Sascha Hauer; Stefan
> > > Agner; linux- kernel@vger.kernel.org; netdev@vger.kernel.org; Jeff
> > > Kirsher; Uwe Kleine- König
> > > Subject: [PATCH 0/3] net: fec: Reset ethernet PHY whenever the
> > > enet_out clock
> > >
> > > This patchset fixes a regression introduced by commit 8fff755e9f8d
> ("net:
> > > fec: Ensure clocks are enabled while using mdio bus") for ethernet
> > > PHYs that are using ENET_OUT as reference clock (on i.MX6 or i.MX28)
> > >
> > Do you mean commit 8fff755e9f8d cause your problem ? This commit just
> manage ipg clock in runtime because mdio bus can access external phy
> switch no matter netdev status.
> >
> No. Actually I meant commit e8fcfcd5684a ("net: fec: optimize the clock
> management to save power") which started to disable the clocks when not
> in use.
>
Understand. Yes, disable enet_out clock for power saving is necessary.

> Sorry for the confusion,
> Lothar Waßmann