Re: enetc: fix bitfields, we are clearing wrong bits

[Vladimir Oltean]

On Sun, Mar 21, 2021 at 07:44:19PM +0200, Vladimir Oltean wrote:
> On Sun, Mar 21, 2021 at 05:25:00PM +0100, Pavel Machek wrote:
> > Bitfield manipulation in enetc_mac_config() looks wrong. Fix
> > it. Untested.
> > 
> > Signed-off-by: Pavel Machek (CIP) <pavel@xxxxxxx>
> > 
> > diff --git a/drivers/net/ethernet/freescale/enetc/enetc_pf.c b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
> > index 224fc37a6757..b85079493933 100644
> > --- a/drivers/net/ethernet/freescale/enetc/enetc_pf.c
> > +++ b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
> > @@ -505,7 +505,7 @@ static void enetc_mac_config(struct enetc_hw *hw, phy_interface_t phy_mode)
> >  	if (phy_interface_mode_is_rgmii(phy_mode)) {
> >  		val = enetc_port_rd(hw, ENETC_PM0_IF_MODE);
> >  		val &= ~ENETC_PM0_IFM_EN_AUTO;
> > -		val &= ENETC_PM0_IFM_IFMODE_MASK;
> > +		val &= ~ENETC_PM0_IFM_IFMODE_MASK;
> >  		val |= ENETC_PM0_IFM_IFMODE_GMII | ENETC_PM0_IFM_RG;
> >  		enetc_port_wr(hw, ENETC_PM0_IF_MODE, val);
> >  	}
> > 
> > -- 
> > DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
> > HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
> 
> Fixes: c76a97218dcb ("net: enetc: force the RGMII speed and duplex instead of operating in inband mode")
> Reviewed-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
> 
> Note that for normal operation, the bug was inconsequential, due to the
> fact that we write the IF_MODE register in two stages, first in
> .phylink_mac_config (which incorrectly cleared out a bunch of stuff),
> then we update the speed and duplex to the correct values in
> .phylink_mac_link_up. Maybe loopback mode was broken.
> 
> Thanks!

I forgot to mention, target tree should be "net" and patch should be
queued up for stable.