Am Dienstag, den 15.05.2018, 10:18 +0200 schrieb Marco Felsch: > From: Markus Niebel <Markus.Niebel@xxxxxx> > > The micrel KSZ9031 phy has a optional clock pin (CLK125_NDO) which can be > used as reference clock for the MAC unit. The clock signal must meet the > RGMII requirements to ensure the correct data transmission between the > MAC and the PHY. The KSZ9031 phy does not fulfill the duty cycle > requirement if the phy is configured as slave. For a complete > describtion look at the errata sheets: DS80000691D or DS80000692D. > > The errata sheet recommends to force the phy into master mode whenever > there is a 1000Base-T link-up as work around. Only set the > "micrel,force-master" property if you use the phy reference clock provided > by CLK125_NDO pin as MAC reference clock in your application. > > Attenation, this workaround is only usable if the link partner can > be configured to slave mode for 1000Base-T. > Thank you for documenting and bringing it mainline, should be clear enough what the modification is meant for. Markus -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html