On Tue, Feb 07, 2023 at 03:41:35PM +0100, Clément Léger wrote: > Le Mon, 16 Jan 2023 10:53:49 +0000, > "Russell King (Oracle)" <linux@xxxxxxxxxxxxxxx> a écrit : > > > On Mon, Jan 16, 2023 at 11:39:23AM +0100, Clément Léger wrote: > > > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > > > index f2247b8cf0a3..88c941003855 100644 > > > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > > > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c > > > @@ -3818,6 +3818,12 @@ static int __stmmac_open(struct net_device *dev, > > > } > > > } > > > > > > + /* We need to setup the phy & PCS before accessing the stmmac registers > > > + * because in some cases (RZ/N1), if the stmmac IP is not clocked by the > > > + * PCS, hardware init will fail because it lacks a RGMII RX clock. > > > + */ > > > + phylink_start(priv->phylink); > > > > So what happens if you end up with the mac_link_up method being called > > at this point in the driver, before the hardware has been setup ? > > > > If you use a fixed-link, that's a real possibility. > > I actually have this setup. On the board, one GMAC is connected to a > DSA switch using a fixed-link and the other using the PCS such as added > by this series. > > From what I see, indeed, the mac_link_up() function is called before > stmmac_hw_setup(). This does not seems to have any effect on my setup > (except making it working of course) but I agree this is clearly not > ideal. > > What I could do is adding a function in the miic pcs driver that could > be called from my rzn1 stmmac probe function to actually configure the > PCS at probe time based on the detected "phy-mode". Does that seems > better to you ? I think Clark Wang is also working on addressing a very similar problem with stmmac. Please can you check out his work first, he's adding a new function to phylink to bring the PHY up early in the resume path. I would like you both to work together to address what seems to be the same issue. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!
