On Mon, Apr 08, 2019 at 11:26:28PM +0200, Andrew Lunn wrote: > On Mon, Apr 08, 2019 at 10:31:48AM +0200, Simon Horman wrote: > > * According to the R-Car Gen3 Hardware Manual Errata for Rev 1.00 of > > August 24, 2018, the TX clock internal delay mode isn't supported > > on R-Car E3 (r8a77990) and D3 (r8a77995). > > > > * TX clock internal delay mode is required for reliable 1Gbps communication > > using the KSZ9031RNX phy present on the Ebisu and Draak boards. > > Hi Simon > > My reading of the KSZ9031RNX datasheet suggests the PHY can perform > the delays. MMD address 2h, Register 8h - RGMII Clock Pad Skew. > > The PHY driver might even have the needed vendor specific DT > properties. > > Have you look at using this? Thanks for the suggestion Andrew, I will ask Renesas about this.
