The DP83869 PHY transceiver supports converting from RGMII to 1000base-x. In this operation mode, autonegotiation can be performed, as described in IEEE802.3. The DP83869 has a set of fiber-specific registers located at offset 0xc00. When the transceiver is configured in RGMII-to-1000base-x mode, these registers are mapped onto offset 0, which should make reading the autonegotiation status transparent. However, the fiber registers at offset 0xc04 and 0xc05 follow the bit layout specified in Clause 37, and genphy_read_status() assumes a Clause 22 layout. Thus, genphy_read_status() doesn't properly read the capabilities advertised by the link partner, resulting in incorrect link parameters. Similarly, genphy_config_aneg() doesn't properly write advertised capabilities. Fix the 1000base-x autonegotiation procedure by replacing genphy_read_status() and genphy_config_aneg() with their Clause 37 equivalents. Fixes: a29de52ba2a1 ("net: dp83869: Add ability to advertise Fiber connection") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Romain Gantois <romain.gantois@xxxxxxxxxxx> --- Changes in v3: - Used the genphy_c37 helpers instead of custom logic - Link to v2: https://lore.kernel.org/r/20241104-dp83869-1000base-x-v2-1-f97e39a778bf@xxxxxxxxxxx Changes in v2: - Fixed an uninitialized use. - Link to v1: https://lore.kernel.org/r/20241029-dp83869-1000base-x-v1-1-fcafe360bd98@xxxxxxxxxxx --- drivers/net/phy/dp83869.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) diff --git a/drivers/net/phy/dp83869.c b/drivers/net/phy/dp83869.c index 5f056d7db83eed23f1cab42365fdc566a0d8e47f..b6b38caf9c0ed0b3ae12a2af7e56754e3ece642f 100644 --- a/drivers/net/phy/dp83869.c +++ b/drivers/net/phy/dp83869.c @@ -153,19 +153,32 @@ struct dp83869_private { int mode; }; +static int dp83869_config_aneg(struct phy_device *phydev) +{ + struct dp83869_private *dp83869 = phydev->priv; + + if (dp83869->mode != DP83869_RGMII_1000_BASE) + return genphy_config_aneg(phydev); + + return genphy_c37_config_aneg(phydev); +} + static int dp83869_read_status(struct phy_device *phydev) { struct dp83869_private *dp83869 = phydev->priv; + bool changed; int ret; + if (dp83869->mode == DP83869_RGMII_1000_BASE) + return genphy_c37_read_status(phydev, &changed); + ret = genphy_read_status(phydev); if (ret) return ret; - if (linkmode_test_bit(ETHTOOL_LINK_MODE_FIBRE_BIT, phydev->supported)) { + if (dp83869->mode == DP83869_RGMII_100_BASE) { if (phydev->link) { - if (dp83869->mode == DP83869_RGMII_100_BASE) - phydev->speed = SPEED_100; + phydev->speed = SPEED_100; } else { phydev->speed = SPEED_UNKNOWN; phydev->duplex = DUPLEX_UNKNOWN; @@ -898,6 +911,7 @@ static int dp83869_phy_reset(struct phy_device *phydev) .soft_reset = dp83869_phy_reset, \ .config_intr = dp83869_config_intr, \ .handle_interrupt = dp83869_handle_interrupt, \ + .config_aneg = dp83869_config_aneg, \ .read_status = dp83869_read_status, \ .get_tunable = dp83869_get_tunable, \ .set_tunable = dp83869_set_tunable, \ --- base-commit: 20bbe5b802494444791beaf2c6b9597fcc67ff49 change-id: 20241025-dp83869-1000base-x-0f0a61725784 Best regards, -- Romain Gantois <romain.gantois@xxxxxxxxxxx>