Hi Andrew, 于 Thu, 10 Jun 2021 16:42:24 +0200 Andrew Lunn <andrew@xxxxxxx> 写道: > > We are much more strict about this now than before. You have to > > use standard units and convert to hardware values. It also makes it > > a lot easier for DT writers, if they have an idea what the units > > mean. > > > > Having the MAC add small delays is something you can add later, > > without breaking backwards compatibility. So if you cannot > > determine what the units are now, just submit the glue driver > > without support for this feature. If anybody really needs it, they > > can do the needed research, maybe do some measurements, and then > > add the code. > > > > > > I did an experiment, when the tx delay is not set, RGMII works a > > You had rgmii-id in your device tree, so that the PHY added the > delays? I have tried rgmii-id and rgmii-txid. If we don’t add a fine-tuning parameter, it still can’t work properly. In these two modes, we still need to add about 500ps delay on the mac side to ensure it works properly. Thanks and best regards! > > Andrew