Re: [PATCH net-next 3/6] net: stmmac: start phylink before setting up hardware
From: "Russell King (Oracle)" <linux@armlinux.org.uk>
Date: 2023-01-16 10:55:50
Also in:
linux-arm-kernel, linux-devicetree, linux-renesas-soc, lkml
On Mon, Jan 16, 2023 at 11:39:23AM +0100, Clément Léger wrote:
quoted hunk ↗ jump to hunk
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. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!