On Sun, Oct 25, 2020 at 03:16:36PM +0100, Ard Biesheuvel wrote: > On Sun, 18 Oct 2020 at 17:45, Andrew Lunn <and...@lunn.ch> wrote: > > > > > However, that leaves the question why bbc4d71d63549bcd was backported, > > > although I understand why the discussion is a bit trickier there. But > > > if it did not fix a regression, only broken code that never worked in > > > the first place, I am not convinced it belongs in -stable. > > > > Please ask Serge Semin what platform he tested on. I kind of expect it > > worked for him, in some limited way, enough that it passed his > > testing. > > > > I'll make a note here that a rather large number of platforms got > broken by the same fix for the Realtek PHY driver: > > https://lore.kernel.org/lkml/?q=bbc4d71d6354 > > I seriously doubt whether disabling TX/RX delay when it is enabled by > h/w straps is the right thing to do here.
The device tree is explicitly asking for rgmii. If it wanted the hardware left alone, it should of used PHY_INTERFACE_MODE_NA. But we might be able to compromise for a cycle or two. As far as i understand the hardware, we can read the strapping. If we find the strapping resisters are present, but rgmii is in DT, print a warning that the device tree needs upgrading, and ignore the DT mode. We can add this to stable, but not net-next. Andrew