This is a note to let you know that I've just added the patch titled net: phy: marvell10g: fix 88x3310 power up to the 5.10-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-phy-marvell10g-fix-88x3310-power-up.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 619c9956b88c968d91cdeb46ab9173b55c53d89c Author: Jiawen Wu <jiawenwu@xxxxxxxxxxxxxx> Date: Wed Jul 19 17:22:33 2023 +0800 net: phy: marvell10g: fix 88x3310 power up [ Upstream commit c7b75bea853daeb64fc831dbf39a6bbabcc402ac ] Clear MV_V2_PORT_CTRL_PWRDOWN bit to set power up for 88x3310 PHY, it sometimes does not take effect immediately. And a read of this register causes the bit not to clear. This will cause mv3310_reset() to time out, which will fail the config initialization. So add a delay before the next access. Fixes: c9cc1c815d36 ("net: phy: marvell10g: place in powersave mode at probe") Signed-off-by: Jiawen Wu <jiawenwu@xxxxxxxxxxxxxx> Reviewed-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/phy/marvell10g.c b/drivers/net/phy/marvell10g.c index 2b64318efdba6..42b48d0d0c4ed 100644 --- a/drivers/net/phy/marvell10g.c +++ b/drivers/net/phy/marvell10g.c @@ -263,6 +263,13 @@ static int mv3310_power_up(struct phy_device *phydev) ret = phy_clear_bits_mmd(phydev, MDIO_MMD_VEND2, MV_V2_PORT_CTRL, MV_V2_PORT_CTRL_PWRDOWN); + /* Sometimes, the power down bit doesn't clear immediately, and + * a read of this register causes the bit not to clear. Delay + * 100us to allow the PHY to come out of power down mode before + * the next access. + */ + udelay(100); + if (phydev->drv->phy_id != MARVELL_PHY_ID_88X3310 || priv->firmware_ver < 0x00030000) return ret;