This is a note to let you know that I've just added the patch titled net: fec: Fix PHY init after phy_reset_after_clk_enable() to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-fec-fix-phy-init-after-phy_reset_after_clk_enable.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Sat Oct 17 12:48:24 PM CEST 2020 From: Marek Vasut <marex@xxxxxxx> Date: Tue, 6 Oct 2020 15:52:53 +0200 Subject: net: fec: Fix PHY init after phy_reset_after_clk_enable() From: Marek Vasut <marex@xxxxxxx> [ Upstream commit 0da1ccbbefb662915228bc17e1c7d4ad28b3ddab ] The phy_reset_after_clk_enable() does a PHY reset, which means the PHY loses its register settings. The fec_enet_mii_probe() starts the PHY and does the necessary calls to configure the PHY via PHY framework, and loads the correct register settings into the PHY. Therefore, fec_enet_mii_probe() should be called only after the PHY has been reset, not before as it is now. Fixes: 1b0a83ac04e3 ("net: fec: add phy_reset_after_clk_enable() support") Reviewed-by: Andrew Lunn <andrew@xxxxxxx> Tested-by: Richard Leitner <richard.leitner@xxxxxxxxxxx> Signed-off-by: Marek Vasut <marex@xxxxxxx> Cc: Christoph Niedermaier <cniedermaier@xxxxxxxxxxxxxxxxxx> Cc: David S. Miller <davem@xxxxxxxxxxxxx> Cc: NXP Linux Team <linux-imx@xxxxxxx> Cc: Shawn Guo <shawnguo@xxxxxxxxxx> Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/freescale/fec_main.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) --- a/drivers/net/ethernet/freescale/fec_main.c +++ b/drivers/net/ethernet/freescale/fec_main.c @@ -2950,17 +2950,17 @@ fec_enet_open(struct net_device *ndev) /* Init MAC prior to mii bus probe */ fec_restart(ndev); - /* Probe and connect to PHY when open the interface */ - ret = fec_enet_mii_probe(ndev); - if (ret) - goto err_enet_mii_probe; - /* Call phy_reset_after_clk_enable() again if it failed during * phy_reset_after_clk_enable() before because the PHY wasn't probed. */ if (reset_again) fec_enet_phy_reset_after_clk_enable(ndev); + /* Probe and connect to PHY when open the interface */ + ret = fec_enet_mii_probe(ndev); + if (ret) + goto err_enet_mii_probe; + if (fep->quirks & FEC_QUIRK_ERR006687) imx6q_cpuidle_fec_irqs_used(); Patches currently in stable-queue which might be from marex@xxxxxxx are queue-4.19/net-fec-fix-phy_device-lookup-for-phy_reset_after_clk_enable.patch queue-4.19/net-fec-fix-phy-init-after-phy_reset_after_clk_enable.patch