On Thu, 2 Apr 2026 12:24:49 +0530 Ashok Kumar Natarajan <[email protected]> wrote:
> The AXGBE MAC supports only full-duplex operation at all speeds. > However, the PHY auto-negotiation configuration could advertise > half-duplex modes, including 10BASE-T, 100BASE-TX, and 1000BASE-T, > which are not supported by the MAC. > > Update the Clause 22 and Clause 40 PHY advertisement handling to mask > all half-duplex modes while preserving existing PHY, strap, and > vendor-specific configuration using read-modify-write. > > To maintain backward compatibility, full-duplex advertisement for > 10/100 and 1000BASE-T is preserved by default when no explicit PHY > advertising mask is provided. > > This ensures IEEE 802.3 compliant PHY advertisement while avoiding > regressions on platforms relying on PHY default configuration. > > Signed-off-by: Ashok Kumar Natarajan <[email protected]> > --- AI review noticed possible issues with thsi. Which may be an issue, or false positive. > The AXGBE MAC supports only full-duplex operation at all speeds. > However, the PHY auto-negotiation configuration could advertise > half-duplex modes, including 10BASE-T, 100BASE-TX, and 1000BASE-T, > which are not supported by the MAC. > > Update the Clause 22 and Clause 40 PHY advertisement handling to mask > all half-duplex modes while preserving existing PHY, strap, and > vendor-specific configuration using read-modify-write. The read-modify-write approach is good, and the Clause 22 / Clause 40 separation is clean. > + if (!adv) { > + advert |= ADVERTISE_10FULL | ADVERTISE_100FULL; > + } else { The original code unconditionally sets ADVERTISE_PAUSE_CAP: advert |= ADVERTISE_FULL; advert |= ADVERTISE_PAUSE_CAP; In the legacy path (adv == 0), the new code advertises 10/100 full-duplex but drops pause advertisement. This is a behavioral regression for platforms relying on the default configuration -- exactly the scenario the commit message says should avoid regressions. The !adv block should also set ADVERTISE_PAUSE_CAP to match the old behavior. > +#define AXGBE_PHY_MII_CTRL1000_1000T_FULL 0x0200 > +#define AXGBE_PHY_MII_CTRL1000_1000T_HALF 0x0100 These are standard IEEE 802.3 Clause 40 bits. Since axgbe_phy.h already mirrors the Linux MII defines for Clause 22, consider adding these as ADVERTISE_1000FULL / ADVERTISE_1000HALF in the existing MII section for consistency rather than under the M88E1512-specific block.
