From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Crispin Subject: Re: [PATCH 3/3] net-next: mediatek: add RX delay support Date: Thu, 5 May 2016 19:37:35 +0200 Message-ID: References: <1462439856-51788-1-git-send-email-john@phrozen.org> <1462439856-51788-4-git-send-email-john@phrozen.org> <20160505121353.GE7972@lunn.ch> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, linux-mediatek@lists.infradead.org, "David S. Miller" , linux-kernel@vger.kernel.org, nbd@nbd.name To: Andrew Lunn Return-path: In-Reply-To: <20160505121353.GE7972@lunn.ch> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 05/05/2016 14:13, Andrew Lunn wrote: > On Thu, May 05, 2016 at 11:17:36AM +0200, John Crispin wrote: >> If an external Gigabit PHY is connected to either of the MACs we need to >> tell the to use a RX delay. Not doing so will result in heavy packet loss >> and/or data corruption of RX traffic. > > Hi John > > Is this comment correct? Reading the code, all this switch statement > does is select between RGMII, MII and RMII. It has nothing to do with > delay. I suspect the PHY is doing the delay, not the MAC, since you > pass the phy mode to of_phy_connect(). > > If my interpretation of the code is correct, you might also want to > handle PHY_INTERFACE_MODE_RGMII_TXID and PHY_INTERFACE_MODE_RGMII_ID > which are also RGMII modes. > > Andrew Hi Andrew, the comment is indeed incorrect and the PHY needs to handle the delay. i will send a V2 and also add _TXID and _ID John