From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Lunn Subject: Re: [PATCH 1/2] net: ethernet: nb8800: Do not apply TX delay at MAC level Date: Fri, 4 Nov 2016 16:11:51 +0100 Message-ID: <20161104151151.GF3600@lunn.ch> References: <581CA300.1060609@laposte.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: =?iso-8859-1?Q?M=E5ns_Rullg=E5rd?= , "David S. Miller" , netdev , LKML , Mason To: Sebastian Frias Return-path: Content-Disposition: inline In-Reply-To: <581CA300.1060609@laposte.net> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Fri, Nov 04, 2016 at 04:02:24PM +0100, Sebastian Frias wrote: > The delay can be applied at PHY or MAC level, but since > PHY drivers will apply the delay at PHY level when using > one of the "internal delay" declinations of RGMII mode > (like PHY_INTERFACE_MODE_RGMII_TXID), applying it again > at MAC level causes issues. > > Signed-off-by: Sebastian Frias > --- > drivers/net/ethernet/aurora/nb8800.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/aurora/nb8800.c b/drivers/net/ethernet/aurora/nb8800.c > index b59aa35..d2855c9 100644 > --- a/drivers/net/ethernet/aurora/nb8800.c > +++ b/drivers/net/ethernet/aurora/nb8800.c > @@ -1282,7 +1282,7 @@ static int nb8800_tangox_init(struct net_device *dev) > break; > > case PHY_INTERFACE_MODE_RGMII_TXID: > - pad_mode = PAD_MODE_RGMII | PAD_MODE_GTX_CLK_DELAY; > + pad_mode = PAD_MODE_RGMII; > break; How many boards use this Ethernet driver? How many boards are your potentially breaking, because they need this delay? I guess it is a small number, because doesn't it require the PHY is also broken, not adding a delay when it should? Andrew