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 ? Thanks, -- Clément Léger, Embedded Linux and Kernel engineer at Bootlin https://bootlin.com
