On Mon, 04 Nov 2024 09:52:32 +0100 Romain Gantois wrote:
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, in theory, make reading the autonegotiation status transparent.
However, the fiber registers at offset 0xc04 and 0xc05 do not follow the bit layout of their standard counterparts. 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 driver-specific functions which take into account the nonstandard bit layout of the DP83869 registers in 1000base-x mode.
Could we get an ack from PHY maintainers?