This commit ports Linux commit: | commit 3c51fa5d2afe7a4909b53af5019635326389dd29 | Author: Russell King <rmk+kernel@xxxxxxxxxxxxxxx> | Date: Tue Jan 12 22:59:43 2021 +0000 | | net: phy: ar803x: disable extended next page bit | | This bit is enabled by default and advertises support for extended | next page support. XNP is only needed for 10GBase-T and MultiGig | support which is not supported. Additionally, Cisco MultiGig switches | will read this bit and attempt 10Gb negotiation even though Next Page | support is disabled. This will cause timeouts when the interface is | forced to 100Mbps and auto-negotiation will fail. The interfaces are | only 1000Base-T and supporting auto-negotiation for this only requires | the Next Page bit to be set. | | Taken from: | https://github.com/SolidRun/linux-stable/commit/7406c5244b7ea6bc17a2afe8568277a8c4b126a9 | and adapted to mainline kernels by rmk. | | Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx> | Reviewed-by: Andrew Lunn <andrew@xxxxxxx> | Link: https://lore.kernel.org/r/E1kzSdb-000417-FJ@xxxxxxxxxxxxxxxxxxxxxx | Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx> --- drivers/net/phy/at803x.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c index d8a9c3588f..577bdf1244 100644 --- a/drivers/net/phy/at803x.c +++ b/drivers/net/phy/at803x.c @@ -365,7 +365,13 @@ static int at803x_config_init(struct phy_device *phydev) if (ret < 0) return ret; - return 0; + /* Ar803x extended next page bit is enabled by default. Cisco + * multigig switches read this bit and attempt to negotiate 10Gbps + * rates even if the next page bit is disabled. This is incorrect + * behaviour but we still need to accommodate it. XNP is only needed + * for 10Gbps support, so disable XNP. + */ + return phy_modify(phydev, MII_ADVERTISE, MDIO_AN_CTRL1_XNP, 0); } static struct phy_driver at803x_driver[] = { -- 2.39.2
